Declaration of Sanjay Banerjee, Ph.D., in Support of Petition for … · 2017. 5. 29. · Petition...

UNITED STATES PATENT AND TRADEMARK OFFICE ______________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD

______________________

MICRON TECHNOLOGY, INC., Petitioner

v.

PRESIDENT AND FELLOWS OF HARVARD COLLEGE, Patent Owner

________________________

Case IPR. No. Unassigned U.S. Patent No. 6,969,539

Title: VAPOR DEPOSITION OF METAL OXIDES, SILICATES AND PHOSPHATES, AND SILICON DIOXIDE

________________________

Declaration of Sanjay Banerjee, Ph.D., in Support of Petition for Inter Partes Review

of U.S. Patent No. 6,969,539

MICRON Ex.1003 p.1

Petition for Inter Partes Review of 6,969,539 Ex.1003 (“Banerjee Decl.”)

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TABLE OF CONTENTS Page

I. INTRODUCTION AND QUALIFICATIONS ............................................... 1 II. MATERIALS RELIED ON IN FORMING MY OPINIONS ........................ 5 III. UNDERSTANDING OF THE GOVERNING LAW ..................................... 6

A. Anticipation ........................................................................................... 6 B. Invalidity by Obviousness ..................................................................... 7

IV. LEVEL OF ORDINARY SKILL IN THE ART ............................................. 9 V. OVERVIEW OF THE TECHNOLOGY AND THE 539 PATENT ............. 11

A. Technology Background ..................................................................... 12 1. Chemical Vapor Deposition Processes .................................... 12 2. Atomic Layer Deposition Processes ........................................ 18 3. Benefits of ALD ....................................................................... 26 4. Materials Used in ALD of Metal-Containing Films ................ 30 5. ALD to Deposit Films As Device Dimensions Decreased ...... 36

B. The 539 Patent ..................................................................................... 39 VI. 539 PATENT PROSECUTION HISTORY .................................................. 42

A. Prosecution of 539 Patent .................................................................... 42 B. Prosecution of U.S. Patent No. 8,334,016 ........................................... 44

VII. CLAIM CONSTRUCTION .......................................................................... 46 VIII. THE PRIOR ART .......................................................................................... 47

A. Csaba Dücsö, et al., Deposition of Tin Oxide into Porous Silicon by Atomic Layer Epitaxy (“Dücsö”) ...................................... 47

B. A.W. Ott, et al., Modification of Porous Alumina Membranes Using Al2O3 Atomic Layer Controlled Deposition (“Ott”) ................ 50

C. U.S. Patent No. 6,984,591 (“Buchanan”) ............................................ 53 D. U.S. Patent No. 6,159,855 (“Vaartstra”) ............................................. 58

IX. OPINIONS RELATING TO EACH OF THE GROUNDS .......................... 62 A. Ground 1: Claim 31 Is Rendered Obvious By Dücsö In View

Of Buchanan Under 35 U.S.C. § 103 .................................................. 63

MICRON Ex.1003 p.2


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1. [31.P] “A process as in any one of claims 24, 26, 29 or 30” ............................................................................................ 63

2. [31.1] “in which the metal oxide film covers an aspect ratio over 40.” .......................................................................... 67

3. Motivation to Combine: Dücsö in Combination with Buchanan .................................................................................. 68

B. Ground 2: Claim 31 Is Rendered Obvious By Ott In View Of Vaartstra Under 35 U.S.C. § 103 ........................................................ 77 1. [31.P] “A process as in any one of claims 24, 26, 29 or

30” ............................................................................................ 78 2. [31.1] “in which the metal oxide film covers an aspect

ratio over 40.” .......................................................................... 81 3. Motivation to Combine: Ott in Combination with

Vaartstra ................................................................................... 82 X. GROUNDS OF INVALIDITY ..................................................................... 92 XI. DECLARATION IN LIEU OF OATH ......................................................... 92

MICRON Ex.1003 p.3


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I, Sanjay Banerjee, hereby declare as follows:

I. INTRODUCTION AND QUALIFICATIONS

1. My name is Sanjay Banerjee. I have been retained on behalf of

Petitioner Micron Technology, Inc. (“Micron”) to provide this Declaration

concerning technical subject matter relevant to the petition for inter partes review

(“Petition”) concerning U.S. Patent No. 6,969,539 (Ex.1001, the “539 Patent”). I

reserve the right to supplement this Declaration in response to additional evidence

that may come to light.

2. I am over 18 years of age. I have personal knowledge of the facts

stated in this Declaration and could testify competently to them if asked to do so.

3. My compensation is not based on the outcome of this matter. My

findings are based on my education, experience, and background in the fields

discussed below.

4. I currently serve as the Cockrell Family Regents Chair Professor of

Electrical and Computer Engineering and Director of the Microelectronics

Research Center at the University of Texas at Austin (“UT”). Prior to this

position, I was first an Assistant Professor (September 1987-August 1990) and

later an Associate Professor (September 1990-August 1993) at UT, before being

named a Professor in September 1993. Prior to starting my academic work at UT,

MICRON Ex.1003 p.4


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I was a member of the technical staff at Texas Instruments (Corporate R&D) from

the time I completed my doctoral studies in 1983 until August 1987.

5. In addition to my academic work at UT, I am also the Director of the

South West Academy of Nanoelectronics, one of three centers created by the

Semiconductor Research Corporation Nanoelectronics Research Initiative in 2006

to research and develop a replacement for conventional metal oxide semiconductor

field effect transistors (“MOSFETs”).

6. I received my Ph.D. in Electrical Engineering from the University of

Illinois in 1983. I also received an M.S. in Electrical Engineering from the

University of Illinois in 1981. I received a B. Tech. in Electronics from the Indian

Institute of Technology at Kharagpur in 1979.

7. As described in my CV (Ex.1004), I have more than 30 years of

experience in the field of electrical engineering, including extensive experience in

semiconductor development and fabrication including that of Dynamic Random

Access Memory (“DRAM”), MOSFETs, and beyond-complementary metal-oxide-

semiconductor (“CMOS”) transistors. My work in these fields has resulted in

more than thirty United States patents related to methods of forming transistors and

DRAM cells.

8. Much of my research and experience has related to methods for

depositing films, including chemical vapor deposition and atomic layer deposition.

MICRON Ex.1003 p.5


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A number of the sponsored research grants on which I have been a principal or co-

investigator have related to vapor deposition methods, including “Optoelectronic

Devices by Photo-enhanced Chemical Vapor Deposition” (National Science

Foundation Presidential Young Investigator Award, August 1988-July 1993),

“RPCVD Epitaxial Silicon and Insulators for Use in 3-D CMOS Integrated

Circuits” (Office of Naval Research, September 1987-March 1990), “Atomic

Layer Epitaxy of Group IV Semiconductors” (Office of Naval Research, February

1991-August 1996), and “Si and Ge Thin Film CVD, Modeling and Control” (U.S.

Department of Defense-Multidisciplinary University Research Initiative, July

1995-July 2000). In addition, I am a named author on over seventy publications

relating to chemical vapor deposition and atomic layer deposition between 1984

and the present.

9. I am a Fellow of the Institute of Electrical and Electronics Engineers

(“IEEE”), the American Physical Society (“APS”), and the American Association

for the Advancement of Science (“AAAS”). I have served on numerous

professional and government committees in the electrical engineering field,

including chairing multiple IEEE committees, meetings and programs, serving on

Elsevier Science’s editorial board, and serving as a member on the International

Technology Roadmap for Semiconductors (“ITRS”).

MICRON Ex.1003 p.6


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10. I have received numerous other awards recognizing my extensive

work in the electrical engineering field, which are described in more detail in my

CV. I have taught courses in Semiconductor Physics, Solid State Electronic

Devices, and Microelectronic and VLSI Device Fabrication at UT. In addition, I

have delivered many courses to industry on Semiconductor Devices and Memory

and Semiconductor Processing. As a principal investigator, I have been the

advisor to over 80 Doctoral and Masters students.

11. I am the author of several books and invited book chapters covering

the area of electronic and semiconductor devices including: High-k Gate

Dielectrics, Solid State Electronic Devices (three editions), and Novel 3D CMOS.

I have authored or co-authored more than 1,000 papers and presentations in the

areas of semiconductor devices and electronics development over the course of my

career.

12. I have been the recipient of fifty grants to fund my research from a

variety of funding agencies including the National Science Foundation (“NSF”),

DARPA, the Department of Energy, Semiconductor Research Corporation, the

Department of Defense-Multidisciplinary University Research Initiative, and the

Office of Naval Research.

13. I have received numerous awards for my work, including the NSF

Presidential Young Investigator Award. The NSF Presidential Young Investigator

MICRON Ex.1003 p.7


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Award was1 a highly competitive honor and grant bestowed annually upon

recognized academic leaders in science and engineering.

II. MATERIALS RELIED ON IN FORMING MY OPINIONS

14. In addition to reviewing the 539 Patent, I also have reviewed and

considered the prosecution history of the 539 Patent (Ex.1002). I have also

reviewed and considered the prosecution history of U.S. Pat. No. 8,334,016 (the

“016 Patent,” Ex.1026) and portions of the prosecution history of U.S. Pat. No.

7,507,848 (the “848 Patent,” Ex.1025), both of which claim priority to the same

provisional patent applications and PCT application to which the 539 Patent claims

priority. I have also reviewed and considered the following prior art references

described herein: Csaba Dücsö et al., Deposition of Tin Oxide into Porous Silicon

by Atomic Layer Epitaxy, J. Electrochem. Soc., Vol. 143, No. 2, Feb. 1996, pp.

683-687 (“Dücsö,” Ex.1006); A. W. Ott et al., Modification of Porous Alumina

Membranes Using Al2O3 Atomic Layer Controlled Deposition, Chem. Mater., Vol.

9, No. 3, March 1997, pp. 707-714 (“Ott,” Ex.1007); U.S. Pat. No. 6,984,591, to

Buchanan et al., entitled “Precursor Source Mixtures” (“Buchanan,” Ex.1005); and

1 The NSF Presidential Young Investigator Award was an award given out by the

NSF until 1991, at which time it was replaced with the NSF Young Investigator

Awards and Presidential Faculty Fellows Program.

MICRON Ex.1003 p.8


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U.S. Pat. No. 6,159,855, to Vaartstra, entitled “Organometallic Compound

Mixtures in Chemical Vapor Deposition” (“Vaartstra,” Ex.1008). I have also

reviewed and considered the Patent Owner Preliminary Responses and exhibits

cited therein filed in IPR2017-00662, IPR2017-00663, IPR2017-00664, and

IPR2017-00666. I also have reviewed and considered the background materials

and exhibits cited herein.

III. UNDERSTANDING OF THE GOVERNING LAW

15. I understand that a patent claim is invalid if it is anticipated or

rendered obvious in view of the prior art. I further understand that claims directed

to a genus may be anticipated or rendered obvious by a disclosure in prior art of a

single species within the claimed genus.

A. Anticipation

16. I have been informed that a patent claim is invalid as anticipated

under 35 U.S.C. § 102 if each and every element of the claim, as properly

construed, is found either explicitly or inherently in a single prior art reference.

17. I have been informed that a claim is invalid under 35 U.S.C. § 102(a)

if the claimed invention was patented or published anywhere in the world, before

the applicant’s invention. I further have been informed that a claim is invalid

under 35 U.S.C. § 102(b) if the invention was patented or published anywhere in

the world more than one year prior to the effective filing date of the patent

MICRON Ex.1003 p.9


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application (critical date). I further have been informed that a claim is invalid

under 35 U.S.C. § 102(e) if an invention described by that claim was disclosed in a

U.S. patent granted on an application for a patent by another that was filed in the

U.S. before the date of invention for such a claim.

B. Invalidity by Obviousness

18. I have been informed that a patent claim is invalid as obvious under

35 U.S.C. § 103 if it would have been obvious to a person of ordinary skill in the

art at the time of the invention, taking into account (1) the scope and content of the

prior art, (2) the differences between the prior art and the claims, (3) the level of

ordinary skill in the art, and (4) any so-called “secondary considerations” of non-

obviousness, which may include: (i) “long felt need” for the claimed invention, (ii)

commercial success attributable to the claimed invention, (iii) unexpected results

of the claimed invention, (iv) “copying” of the claimed invention by others, (v)

failure of others, (vi) praise by others, (vii) recognition of a problem, and (viii)

skepticism of experts. I further understand that it is improper to rely on hindsight

in making the obviousness determination. My analysis of the prior art is made

from the perspective of one of ordinary skill in the art as of the time the invention

was made.

MICRON Ex.1003 p.10


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19. I have been informed that a claim can be obvious in light of a single

prior art reference or multiple prior art references. I further understand that

exemplary rationales that may support a conclusion of obviousness include:

(A) Combining prior art elements according to known methods to yield

predictable results;

(B) Simple substitution of one known element for another to obtain

predictable results;

(C) Use of known technique to improve similar devices (or methods or

products) in the same way;

(D) Applying a known technique to a known device (or method or product)

ready for improvement to yield predictable results;

(E) “Obvious to try” – choosing from a finite number of identified,

predictable solutions, with a reasonable expectation of success;

(F) Known work in one field of endeavor may prompt variations of it for use

in either the same field or a different one based on design incentives or other

market forces if the variations are predictable to one of ordinary skill in the art;

(G) Some teaching, suggestion, or motivation in the prior art that would

have led one of ordinary skill to modify the prior art reference or to combine prior

art reference teachings to arrive at the claimed invention.

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IV. LEVEL OF ORDINARY SKILL IN THE ART

20. I understand that factors that may be considered in determining the

level of ordinary skill in the art may include: (A) “type of problems encountered in

the art;” (B) “prior art solutions to those problems;” (C) “rapidity with which

innovations are made;” (D) “sophistication of the technology”; and (E)

“educational level of active workers in the field.” I also understand that every

factor may not be present for a given case, and one or more factors may

predominate. Here, at the time of the alleged invention of the 539 Patent, the

industry was conducting research to find a replacement for silicon dioxide (SiO2)

as the insulating film for various applications (e.g., gate dielectric layer, capacitor

dielectric layer), and research arms of companies and research institutes were

conducting much of this work. The research was being led by those with

considerable skill in the art, typically engineers with doctorate degrees, e.g., Dr.

Gordon, Dr. Leskelä, Dr. Buchanan, Dr. Vaartstra, myself, and individuals in my

research institute to name a few.2 The subject matter of this research was

specialized.

2 See Ex.1027 (Dr. Gordon’s LinkedIn Profile), Ex.1028 (Dr. Leskelä’s LinkedIn

profile), Ex.1029 (Dr. Buchanan’s LinkedIn profile), Ex.1030 (Dr. Vaartstra’s

LinkedIn profile).

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21. Accordingly, in my opinion, a person of ordinary skill in the art at the

time of the claimed inventions would have had at least a Bachelor of Science

degree in electrical engineering, chemical engineering, chemistry, physics,

materials science, or a closely related field, along with at least 5 years of

experience in developing vapor deposition processes to form thin films. An

individual with an advanced degree in a relevant field would require less

experience in developing vapor deposition processes to form thin films.

22. I reserve the right to amend or supplement this declaration if the

Board adopts a definition of a person of ordinary skill other than that described

above, which may change my conclusion or analysis. But should the Board adopt

a higher standard or a slightly lower standard, it would not change my opinion that

claim31 is invalid.

23. My opinions below explain how a person of ordinary skill in the art

would have understood the technology described in the references I have identified

herein around the 2001 time period, which is the approximate date when the PCT

application listed on the face of the 539 Patent was filed. I was a person of at least

ordinary skill in the art in 20013.

3 My use of the 2001 time period reflects my review of the two provisional

applications to which the 539 Patent claims priority, U.S. Provisional Application

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V. OVERVIEW OF THE TECHNOLOGY AND THE 539 PATENT

24. The PCT application for the 539 Patent was filed on September 28,

2001. The 539 Patent issued on November 29, 2005. The 539 Patent claims

priority to a provisional patent application filed on September 28, 2000 and a

separate provisional patent application filed on November 29, 2000. Ex.1001, 539

Patent at 1:6-11.

25. Claim 31 of the 539 Patent relates to a process for forming a metal

oxide, and thus my description of the background technology and of the 539 Patent

will focus on methods for making metal oxides.

Nos. 60/253,917 (“917 application”) and 60/236,283 (“283 application”). Neither

contains any discussion of an aspect ratio over 40. Nor do any of the portions of

the 539 Patent that refer to an aspect ratio over 40 (Figure 3; the discussion found

at 20:4-7; Example 12’s discussion of a substrate having an aspect ratio over 40)

appear in either the 917 or the 283 applications. While I refer to the 2001 time

period as the relevant time period in this declaration, my opinion would not change

in the event that claim 31 of the 539 Patent is accorded a priority date of

September 28, 2000 or November 29, 2000 based on the 283 and 971 provisional

applications.

MICRON Ex.1003 p.14


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26. Before discussing the details of the specification of the 539 Patent, I

will provide some background on the technology used to fabricate metal oxides

using vapor deposition processes.

A. Technology Background

27. The relevant aspects of the 539 Patent relate to vapor deposition

processes for forming various types of films, including metal silicates, metal

phosphates, and metal oxides. First, I will discuss chemical vapor deposition

(“CVD”), an umbrella term for processes used to form solid materials from vapor

phase reactants. Then I will discuss a type of CVD that is now commonly known

as atomic layer deposition (“ALD”), in which reactants are alternately introduced

into a deposition chamber separate from one another.4 Although ALD is a type of

CVD, my discussion of CVD focuses on CVD techniques in which reactants are

co-introduced into a deposition chamber.

1. Chemical Vapor Deposition Processes

28. CVD is a process that forms a thin solid film on a heated surface

through chemical vapor-phase and vapor-surface reactions. Ex.1031, Pierson at

4 While I refer to atomic layer deposition and ALD throughout this declaration, the

technique underlying ALD has been called by many different names, as I will

discuss later. See infra ¶42.

MICRON Ex.1003 p.15


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pp.17, 25-26. CVD is part of a larger class of vapor-deposition processes that

include physical vapor deposition processes (e.g., evaporation, sputtering, and

molecular beam epitaxy). However, CVD differs from these processes in that it

uses chemical reactions rather than simply physical deposition processes. Id.

29. In CVD, reactants (often called “precursors” as they are the precursors

to the desired film) are introduced into a deposition chamber in vaporized or

gaseous form. Id. at pp.26-27. These precursor gases are flowed into a chamber

containing a heated substrate (such as a silicon wafer for fabrication of a

microelectronic device, a solar cell component, or a light-emitting diode (“LED”)

film) on which a film is to be deposited. Id. at p.17. In most CVD processes, the

precursor gases come into contact with one another and chemically react in the

vapor phase, leading to by-products which then react with the heated substrate

surface, resulting in a thin film being deposited on the substrate surface. Id. at

pp.25, 38. The precursors are selected according to what type of film is desired.

For instance, if a zirconium oxide film is desired, typically a zirconium-containing

compound and an oxidant (such as water, oxygen gas, ozone, or another oxygen-

containing molecule) are used as precursors.

30. In traditional CVD, all of the precursors for a desired film are

introduced into the deposition chamber at the same time, and thus chemical

reactions between precursors occur in the gas phase and on the substrate surface in

MICRON Ex.1003 p.16


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the deposition chamber. Ex.1018, Min at p.7. In CVD, the substrate is often

heated to high temperatures. Ex.1031, Pierson at pp.36-38.

31. CVD has been known for over a century. Early examples of CVD to

deposit metals date from the 1880s.

32. As stated above, CVD is an umbrella term that encompasses a number

of vapor deposition techniques. These techniques include: thermal CVD (in which

the chemical reactions are encouraged or started using heat); photo-assisted CVD

(in which the chemical reactions are encouraged or started using radiation such as

ultraviolet light); plasma-enhanced CVD (in which the chemical reactions are

encouraged or started using electrical energy to create a plasma out of the

precursor gases in which at least some of the atoms/molecules in the precursor gas

become chemically active ions and radicals); and metal-organic CVD (“MOCVD”)

(which utilizes metal-organic compounds as precursors). Ex.1031, Pierson at

pp.17-18.

33. While conventional CVD can be useful for vapor deposition, it also

presents distinct problems. For example, CVD often requires high deposition

temperatures at which substrates may not be thermally stable. Ex.1031, Pierson at

pp.17-18; see also Ex.1032, Fix at p.6 (explaining that “temperatures required for

these CVD reactions are not compatible with thermally sensitive substrates, such

MICRON Ex.1003 p.17


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as those used in the processing of semiconductor components (e.g., aluminized

silicon chips and amorphous silicon solar cells)”).

34. Another problem is that when performing CVD, there is often

insufficient control of the uniformity and/or thickness of the deposited film. There

are a number of reasons for this. First, control over film thickness during CVD is

analog—as long as there is a supply of undeposited reactants available in the

chamber, the deposition process will continue, and the film thickness is thus

generally proportional to the growth time, excluding some initial incubation

period. Because of this, thickness of the growing film must be controlled by

adjusting the concentration of reactants that are introduced into the chamber, the

temperature, and the length of time that the deposition reaction is allowed to occur,

which does not allow precise control of film thickness. Second, precursor

molecules, especially where the precursor is particularly reactive, often react

directly at their first point of contact/impact with the growth surface. Ex.1033,

Gates at p.6. Surface roughness and uneven topography often result from such

reactions. Id. Third, there can be a lack of control over gas-phase reactions, which

can lead to homogeneous gas-phase nucleation of particles which deposit material

on the substrate. Ex.1034, Hampden-Smith at p.5. Depending on the growth

pressure (which controls the mean free path of precursors) and temperature (which

determines the sticking coefficient on the surface), CVD can lead to poor step

MICRON Ex.1003 p.18


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coverage (the ratio of thickness of a film along the vertical and horizontal surfaces

and corners of the topographic features on the substrate). This affects the quality

and uniformity of the deposited film. Ex.10018, Min at p.7; see also Ex.1035,

Suntola II at p.6 (describing the reliance in CVD on a high reaction threshold

between reactants to minimize homogeneous gas-phase reactions which can lead to

particulate formation and decrease film thickness uniformity).

35. A particularly important type of CVD precursor is the metal-organic

category of compounds. Metal-organic precursors are compounds containing

metal and organic (i.e., carbon-containing) ligands. Ex.1034, Hampden-Smith at

p.6. Metal-organic precursors include metal alkoxides, β-diketonato complexes,

cyclopentadienyl compounds, silanes, and alkylamides. Ex.1010, Leskelä II at pp.

18-21.

36. Work on CVD using metal-organic precursors dates back into the

early 1960s. Ex.1031, Pierson at p.65. Before 2001, extensive MOCVD work had

been done, using metal-organic precursors to deposit metal-containing films by

CVD. Id. at pp.74-80; see also Ex.1034, Hampden-Smith at pp.7-8 (listing 30+

metal-organic CVD precursors used by 1995).

37. Before 2001, metal-organic precursors had been used in CVD

processes, for example, to form zirconium and hafnium oxide films. Zirconium

tetra-tert-butoxide, a metal alkoxide (a metal compound wherein an oxygen atom is

MICRON Ex.1003 p.19


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bound to a metal atom and to an organic group), was widely used as a precursor in

forming zirconium oxide thin films by CVD as early as the 1980s. Ex.1036, Smith

at p.10; Ex.1037, Brusasco at p.6. Hafnium tetra-tert-butoxide, a similar metal

alkoxide precursor, was used to form hafnium oxide thin films by CVD in the same

time frame. Ex.1037, Brusasco at p.6.

38. As another example of metal-organic CVD precursors, metal

dialkylamides were widely described in MOCVD processes before 2001. Metal

dialkylamides are metal precursors having an M(NR2) structural unit, in which

“M” is a metal, “N” is nitrogen bound to the metal, and “R” is an alkyl organic

group. Ex.1008, Vaartstra at 4:54-5:18; Ex.1038, Bradley I at p.8. Before 2001,

such compounds were known to be desirable CVD precursors due to their

volatility, high reactivity, ease of preparation and handling, and long shelf life.

Ex.1038, Bradley I at pp.7-8; Ex.1008, Vaartstra at 5:22-27; Ex.1016, Bastianini at

p.17; Ex.1032, Fix at pp.6-7.

39. In 1992, Micron filed a patent application describing the use of a

titanium dialkylamide precursor, tetrakis(dimethylamino) titanium, in the CVD of

titanium nitride/titanium silicide films. Ex.1039, 518 Patent at Abstract, 2:36-42.

CVD processes for forming a metal nitride using metal dialkylamide precursors,

including tetrakis(dimethylamino) tin and hexakis(dimethylamino) dialuminum,

were also described by others in the early 1990s. Ex.1022, 911 Patent at 8:12-19.

MICRON Ex.1003 p.20


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Metal dialkylamides were also taught as precursors in CVD processes to form

metal oxides as early as the 1990s. Ex.1016, Bastianini at p.17; see also Ex.1008,

Vaartstra at 11:8-10 (describing CVD to form films such as metal oxides), 9:32-36

(describing a metal precursor source mixture that includes hexakis(dimethylamino)

dialuminum). Work on metal dialkylamides as precursors in the 1990s showed

that metal dialkylamides could mitigate carbon contamination, a particular problem

observed in films deposited by vapor deposition. See, e.g., Ex.1021, Shin at pp.1,

6; Ex.1051, Lee at pp.11, 14.

2. Atomic Layer Deposition Processes

40. As I described above in the context of CVD, ALD is a type of CVD.

ALD modifies the traditional CVD process by introducing each vaporized

precursor into a deposition chamber alternately and purging the chamber between

the introduction of each precursor, rather than introducing all precursors at the

same time into the chamber. See supra ¶¶27, 29-30.

41. The basic ALD technique was developed over forty years ago. ALD

was originally developed in the 1970s in Finland, by Suntola and colleagues.

Ex.1010, Leskelä II at p.13. Since that time, and as described in more detail

below, those of ordinary skill in the art have performed ALD to deposit a number

of different types of films, including metal oxides, using many different metal

precursors.

MICRON Ex.1003 p.21


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42. Suntola and colleagues originally referred to their invention as

“atomic layer epitaxy,” abbreviated as ALE. Ex.1040, Suntola I at p.6. In the

beginning, Suntola’s technique was used to deposit single crystalline “epitaxial”

films, thus giving rise to the ALE term. Ex.1009, Leskelä I at p.18. However,

ALE was also used in the formation of amorphous and polycrystalline films

(including metals and metal oxides). Id. The use of Suntola’s alternating-

precursor method in non-epitaxial applications resulted in a variety of terms being

used to describe deposition processes carried out under ALE principles. These

terms include: atomic layer deposition, atomic layer processing, chemical vapor

atomic layer deposition, atomic layer growth, successive layer-wise chemisorption,

pulsed beam chemical vapor deposition, sequential surface chemical reaction

growth, molecular layer epitaxy, binary reaction sequence chemistry, and digital

layer epitaxy. Id.; Ex.1015, George I at p.5. By the late 1990s, “atomic layer

deposition” or ALD came to be the popular term for the general principles of

Suntola’s ALE method. Ex.1018, Min at p.7; Ex.1010, Leskelä II at p.13;

Ex.1041, Ritala I at p.4.

43. ALD generally works as follows: Vaporized precursor gases are

pulsed into a deposition chamber containing a substrate alternately, one at a time,

with an evacuation step between precursor pulses to remove any unreacted free

precursor vapor from the chamber (which may be achieved, for example, by

MICRON Ex.1003 p.22


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vacuum-pumping the chamber or by purging the chamber with an inert gas such as

argon). Ex.1009, Leskelä I at p.17. During the alternating pulses, sequential

surface reactions occur in which one component of the desired compound thin film

at a time forms on the substrate surface. Ex.1040, Suntola I at p.6. A key feature

of ALD is that by adjusting the deposition conditions, which is a routine

optimization process in ALD, the sequential surface processes can be made to be

“self-controlling” or “self-limiting,” meaning that film growth does not continue as

a function of time or the availability of precursor gas. Id.; see also Ex.1009,

Leskelä I at p.17 (describing self-controlled processes in the “ALE window”);

Ex.1042, STT at p.13 (referring to the “self-terminating” surface processes that

occur during ALD; “[a]fter all reactive bonds have been occupied by the desired

material, the material will ‘grow’ no further.”); Ex.1043, Goodman at p.8 (“Given

that, any excess incident molecules or atoms impinging on the film do not stick if

the substrate temperature Tgr is properly chosen . . . .”). For example, optimization

of temperature is routinely done to determine when a deposition process transitions

from ALD to CVD, and vice versa. See, e.g., Ex.1018, Min at pp.8-9. Adjustment

of other parameters such as pressure and pulse duration is similarly a routine

procedure performed to optimize ALD processes. See, e.g., Ex.1006, Dücsö at

pp.9-10 (explaining that with “carefully selected pulse durations for the

chemisorption, purge and reaction steps, as well as appropriately chosen pressure

MICRON Ex.1003 p.23


21

and temperature conditions for ALE, a conformal coverage of SnOx on PS was

achieved in the extreme 140:1 aspect ratio pores.”); Ex.1007, Ott at pp.10-11

(describing that longer precursor exposures “may be required for the reactions to

reach completion”).

44. The self-limiting surface deposition processes that can occur during

ALD can be illustrated using growth of zinc sulfide film as an exemplary process:

MICRON Ex.1003 p.24


22

Ex.1009, Leskelä I at p.17.5 In the depiction above, zinc chloride (ZnCl2) is used

as a zinc metal precursor, and hydrogen sulfide (H2S) is used as a sulfur-containing

precursor, to form zinc sulfide (ZnS) through ALD. In the first step (shown to the

right of 1 in the figure above) of this exemplary ALD process, vaporized ZnCl2 is

pulsed into the deposition chamber. The vaporized ZnCl2 adsorbs to the substrate

surface, forming a layer of bound ZnCl2 on the surface. Then in the second step of

this process (shown to the right of 2 in the figure above), the excess, unbound

ZnCl2 is purged out of the chamber, leaving only the ZnCl2 molecules already

bound to the surface in a single layer. Id. Importantly, because ZnCl2 is the only

reactant that has thus far been introduced into the reaction chamber, under ALD

conditions it adsorbs onto the substrate surface in a single layer. In the third step

(shown to the right of 3 in the figure above), vaporized H2S is introduced into the

chamber. The H2S molecules react with the bound ZnCl2, causing an exchange

reaction in which the chlorine atoms bound to the zinc attached to the substrate

surface are exchanged for sulfur atoms, leaving hydrogen chloride (HCl) as a by-

product. In the fourth and final step of this process (shown to the right of 4 in the

5 The numbers on the left side of this figure do not appear in the original version,

taken from Ex.1009, Leskelä I. I have added them here to assist in my explanation

of this figure.

MICRON Ex.1003 p.25


23

figure above), the unreacted H2S molecules and the HCl by-product molecules are

purged out of the chamber, leaving only a monolayer of ZnS on the substrate

surface. Id. This deposition process is referred to as “self-limiting” because it

self-terminates even when excess unreacted precursor is present in the chamber,

rather than continuing until there is no more free precursor available. In this

exemplary ALD process, one complete cycle consists of the following: (1) pulsing

in vaporized ZnCl2 (the first reactant); (2) purging the chamber to remove all

remaining unreacted vaporized ZnCl2; (3) pulsing in vaporized H2S (the second

reactant); (4) purging the chamber to remove all remaining unreacted vaporized

H2S as well as the HCl byproduct that results from the deposition reactions. See

also Ex.1044, Ritala II at p.7. This cycle is repeated in ALD until the desired film

thickness is reached.

45. As depicted in the figure above, ALD can result in a monolayer (or

fraction thereof) of the desired film being deposited per growth cycle. Ex.1035,

Suntola II at p.5; Ex.1009, Leskelä I at p.17; Ex.1015, George I at p.5. This is a

key difference between ALD and other types of CVD: while other forms of CVD

are discussed in terms of growth rate over a period of time when the substrate is

exposed to the precursors, film growth when ALD is made to be self-limiting is not

time-dependent but rather cycle-dependent. That is, self-limiting ALD growth is

discussed in terms of growth per cycle, rather than over a period of time. Ex.1007,

MICRON Ex.1003 p.26


24

Ott at p.7 (“The important advantage of ALE/ALP film growth is that the film

thickness is dependent not on the kinetics of the reaction but only on the number of

reaction cycles.”); see also Ex.1043, Goodman at p.8; Ex.1009, Leskelä I at p.17.

46. Ideally, self-limiting ALD results in a full monolayer of the desired

film being deposited during each ALD cycle. However, due to steric hindrance of

the adsorbed precursor molecules (in which the adsorbed precursor molecules are

large enough to “block” another precursor molecule from binding to the surface

very close to the already-adsorbed molecule), often less than a full monolayer

results from each ALD cycle. Ex.1009, Leskelä I at p.17; Ex.1035, Suntola II at

p.5. It is thus not unusual in ALD that multiple cycles are needed to achieve a full

monolayer of the desired film. See, e.g., Ex.1009, Leskelä I at p.17 (explaining

that 2-3 ALD cycles are needed to grow a full monolayer of ZnS, while 5-6 ALD

cycles are needed to grow a full monolayer of a cadmium sulfide (CaS) film).

47. As discussed above, those of ordinary skill in the art recognized prior

to 2001 that in practice, it is necessary to test various deposition conditions when

performing ALD, including variation of parameters such as deposition temperature

and duration of precursor exposure, to determine which conditions will achieve

self-limiting growth. See supra ¶43. This was a routine procedure for those of

ordinary skill prior to 2001. See, e.g., Ex.1018, Min at pp. 8-10 (describing testing

MICRON Ex.1003 p.27


25

of various deposition temperatures and reactant pulse times when performing ALD

to determine at which conditions the saturation level is reached).

48. In developing ALD methods to deposit a desired film, it was routine

and common for those of ordinary skill in the art to look to CVD processes for

depositing the desired film and the precursors used in those CVD processes. See,

e.g., Ex.1045, George II at p.9 (“A generic recipe for ALD is to find a CVD

process based on a binary reaction and then to apply the A and B reactants

separately and sequentially in an ABAB… binary reaction sequence.”)6; Ex.1036,

Smith at p.9 (“A brief survey of the precursors used for the chemical vapour

deposition of the dioxides of titanium, zirconium and hafnium is presented. The

review covers precursors used for the closely related process known as atomic

layer chemical vapour deposition (ALCVD or ALD).”) Those of ordinary skill in

the art recognized, prior to 2001, a great deal of overlap between the precursors

used in CVD processes and those used in ALD processes. See, e.g., Ex. 1036,

Smith at p.9 (“A brief survey of the precursors used for the chemical vapour

deposition of the dioxides of titanium, zirconium and hafnium is presented. The

6 Although George II is a 2010 review article, in my opinion it reflects the thinking

of those of ordinary skill in the art prior to 2001 that CVD precursors were highly

relevant to, and frequently used in, the development of ALD processes.

MICRON Ex.1003 p.28


26

review covers precursors used for the closely related process known as atomic

layer chemical vapour deposition (ALCVD or ALD).”).

3. Benefits of ALD

49. ALD provides a number of distinct advantages over other forms of

CVD that have made it a very popular and widely-used technique to deposit thin

films in semiconductor fabrication. Such advantages were well-known before

2001.

(a) ALD May Be Performed at Low Temperatures

50. For example, ALD can provide a high-quality film at low

temperatures. Ex.1046, Ritala III at p.9. As I discussed above, the high

temperatures sometimes required for CVD can be detrimental to thermally

sensitive substrates. See supra ¶33. Additionally, some precursors may thermally

decompose at the high temperatures used in CVD. Because ALD can be conducted

at lower temperatures, such thermal decomposition of precursors may be more

easily avoided. See, e.g., Ex.1018, Min at p.9 (describing saturation of film

thickness per cycle, thus achieving a self-limiting process, in ALD at a temperature

lower than that at which the precursor begins to thermally decompose).

(b) ALD Yields Superior Control Over Film Thickness

51. As another example, ALD yields precise control and accuracy over

the thickness of a deposited thin film, as a result of the ability to make the ALD

growth process self-limiting. Ex.1043, Goodman at p.8 (describing the “absolute

MICRON Ex.1003 p.29


27

control of deposit thickness in terms of the number of cycles employed” which

results from a self-limiting ALE approach); see also Ex.1009, Leskelä I at p.18;

Ex.1046, Ritala III at p.9. Such thickness control is further achieved in a

straightforward way by calculating the number of needed growth cycles, without

the need to perform thickness monitoring throughout the deposition process.

Ex.1007, Ott at p.7; Ex.1040, Suntola I at p.8; Ex.1010, Leskelä II at p.13.

(c) ALD Can Deposit Uniform, Conformal Films To Cover High-Aspect Ratio Structures

52. Another advantage of ALD over other types of CVD is that ALD

achieves uniform film growth over large areas. Ex.1040, Suntola I at p.8; Ex.1046,

Ritala III at p.9; Ex.1010, Leskelä II at p.13. This feature of ALD is directly

related to the self-limited surface processes that can take place in ALD—as

discussed above, when the surface processes taking place in the deposition process

are self-limiting, the film growth rate is not dependent on the reaction rate of the

precursors at the surface of the substrate. Ex.1040, Suntola I at p.8; Ex.1010,

Leskelä II at p.13. Rather, when carried out under self-limiting conditions,

deposition in ALD will terminate when all available ligands on the substrate

surface are bound by reactant molecules, even if there is an excess of free reactant

present in the chamber. Moreover, in ALD, heterogeneous nucleation at the vapor-

substrate interface (the process that occurs when molecules arrange themselves on

MICRON Ex.1003 p.30


28

the substrate surface) only occurs in two dimensions, thus ensuring uniformity of

layers in ultra-thin structures. Ex.1040, Suntola I at pp.8-10.

53. ALD’s superior conformality and step coverage is another feature that

results from the self-limiting processes that can occur during this type of

deposition and from the lack of fluctuation in reactant flow. Ex.1009, Leskelä I at

p.18; Ex.1046, Ritala III at p.9; Ex.1041, Ritala I at pp.4-5. Indeed, the excellent

conformality achieved in ALD was a main motivation for the initial research into

ALD. Ex.1035, Suntola II at p.7.

54. The superior step coverage that ALD can achieve makes ALD

particularly well-suited for depositing films, such as metal oxides, in structures

having high aspect ratios. In the continuous deposition that occurs in CVD, the

openings in structures having high aspect ratios can be occluded or “pinched off”

due to uncontrolled film growth over the opening of the structure. However, in

self-limiting ALD, approximately one monolayer of the desired film is deposited

per ALD cycle. Thus, there is far less potential for occlusion or “pinching off” of

the structure’s opening to occur. Those of ordinary skill in the art recognized this

to be true at least in the 1990s. For example, it was noted in 1996 that ALD was

one of the “most promising techniques available for conformal coating of the

surface in porous single-crystalline materials,” and the technique was used to form

a metal oxide in a structure having an extremely high (140:1) aspect ratio.

MICRON Ex.1003 p.31


29

Ex.1006, Dücsö at p.6. The binary reaction sequence chemistry that occurs when

ALD is carried out under self-limiting conditions, and the resulting predictability

in growth per ALD cycle, is what makes ALD particularly effective for achieving

conformal deposition in high-aspect ratio structures. Ex.1007, Ott at p.12 (“This

behavior illustrates that highly controlled and conformal deposition can be

achieved in pores with high aspect ratios using binary reaction sequence

chemistry.”); Ex.1011, Geusic at 7:5-7:10 (“The atomic layer epitaxy technique

deposits material with a thickness of 1 to 2 angstroms for a single binary reaction

sequence. Thus, the technique advantageously allows the high aspect ratio holes

that house the optical fibers to be lined with a uniform cladding layer”). Those of

ordinary skill in the art further recognized, by the 1990s, that the advantages of

ALD (including precise thickness control and superior conformality, including in

high-aspect ratio structures) would be of particular benefit as electronic device

dimensions continued to shrink. Ex.1011, Geusic at 1:47-54 (“A continuing

challenge in the semiconductor industry is to find new, innovative, and efficient

ways of forming electrical connections with and between circuit devices which are

fabricated on the same and on different wafers or dies. . . . As device dimensions

continue to shrink, these challenges become even more important.”), 6:55-7:10

(proposing, accordingly, atomic layer epitaxy as a technique for depositing

material in the high-aspect ratio holes that house optical fibers in an integrated

MICRON Ex.1003 p.32


30

circuit); Ex.1042, SST at pp.6-7 (describing development of high-dielectric

constant gate dielectrics formed by ALD that could serve as alternatives to silicon

dioxide, such as Al2O3, and processes to form such films that “provide[] atomically

uniform films with 100% step coverage on very-high-aspect-ratio features”).

4. Materials Used in ALD of Metal-Containing Films

55. Well before 2001, ALD was used to deposit many different types of

thin films including oxides, nitrides, silicates, phosphates, sulfides, and single-

element films. Ex.1010, Leskelä II at pp.25-28; Ex.1006, Dücsö at pp.6, 9-10;

Ex.1007, Ott at pp.6, 13. Deposition of oxides was, in fact, one of the first

experiments done by ALD when the technique was developed in the 1970s.

Ex.1009, Leskelä I at p.21.

56. Those of ordinary skill used many different types of metal precursors

to deposit metal-containing films by ALD before 2001. See, e.g., Ex.1010, Leskelä

II at p. 18-21, 25-28; Ex.1018, Min at p. 7. In this work, those of ordinary skill

would routinely test precursors in ALD processes under various conditions in order

to determine the conditions that would result in self-limiting ALD. See, e.g.,

Ex.1018, Min at pp. 8-10 (describing testing of various deposition temperatures

and pulse times to determine when the ALD process is self-limiting); Ex.1010,

Leskelä II at pp. 16, 18 (describing finding an “ALE window” or “process window

for 1 ML/cycle” for ALD processes with specific precursors).

MICRON Ex.1003 p.33


31

57. Before 2001, it was known in the art that a number of qualities made

for a desirable ALD precursor. These include reactivity towards surface ligands,

thermal stability against decomposition at ambient temperatures, and volatility

with an adequate window between vaporization temperature and decomposition

temperature. Ex.1010, Leskelä II at pp.13-14; Ex.1008, Vaartstra at 13:65-14:3.

In addition, ideally an ALD precursor does not itself etch the growing film or the

substrate, nor do its by-products. Ex.1010, Leskelä at p.14. In addition to these

characteristics, practical considerations related to precursor stability and ease of

handling are important considerations taken into account by those of ordinary skill

in the art when selecting precursors for ALD and other vapor deposition processes.

Ex.1008, Vaartstra at 5:22-27, 13:65-14:5.

58. It was known before 2001 that in many respects there is much more

versatility with respect to choosing ALD precursors compared to CVD precursors.

Ex.1047, Niinistö at p.6. For example, precursors for both CVD and ALD need to

be volatile so as to facilitate effective transportation into the deposition chamber.

Ex.1010, Leskelä II at pp.13-14. However, there is considerably more flexibility in

ALD with regard to precursor volatility because the use of solid precursors with a

relatively low vapor pressure is feasible in ALD so long as the vapor pressure is

high enough to avoid condensation in the delivery tubes or upon contact with the

heated substrate. Id.; Ex.1046, Ritala III at pp.10-12; Ex.1047, Niinistö at p.6.

MICRON Ex.1003 p.34


32

59. As another example, reactivity with the growth surface is a useful

characteristic in ALD precursors as the process depends upon the precursors

reacting with the substrate or growing film surface. Ex.1010, Leskelä II at p.14.

However, unlike in CVD, where precursors that react aggressively with each other

can be undesirable due to the gas-phase (non-surface) CVD reactions that can lead

to homogeneous nucleation, in ALD (where there is no risk of gas-phase reactions)

aggressive reactivity can be a beneficial characteristic of a precursor. Ex.1047,

Niinistö at p.6.

60. The types of metal precursors that have been used in ALD

applications to form thin films include halides (metals bound to a halogen element,

for example chlorine), alkyl compounds (metals bound to an alkyl group, for

example a methyl (CH3) or ethyl (C2H5) hydrocarbon group), metal alkoxides

(metals bound to oxygen, wherein the oxygen is also bound to an alkyl group),

cyclopentadienyl compounds (metals bound to a C5H5 ring group), and metal

dialkylamides (which are described herein, see supra ¶¶38-39). Ex.1010, Leskelä

II at pp.18-21, 25-28.

61. Before the 539 Patent application was filed in 2001, it was known in

the industry that some types of metal precursors had certain characteristics that

make them undesirable for use in ALD. For many years, metal halides were used

to perform ALD of metal oxide and nitride films. Ex.1009, Leskelä I at p.21;

MICRON Ex.1003 p.35


33

Ex.1047, Niinistö at p.7 (describing in Table 2 processes using various metal

halides to form oxide films). However, it was well known that metal chlorides

could etch films, which is a significant drawback to their utility. Ex.1009, Leskelä

I at p.21. The potential for residual chlorine to be present in the deposited film is

also a major problem when using metal chlorides as precursors in deposition

processes. See, e.g., Ex.1018, Min at p.7; Ex.1010, Leskelä II at p.14; Ex.1039,

518 Patent at 1:51-53. Alkoxides, moreover, pose challenges in achieving an ideal

deposition temperature, since alkoxides can decompose at higher temperatures and

can easily convert between isomeric forms. Ex.1005, Buchanan at 2:23-58;

Ex.1010, Leskelä II at p.19; Ex.1048, Ritala IV at pp.8-15. Metal nitrates, another

type of metal precursor, were known to be extremely sensitive to light, air and

water and to potentially form undesirable by-products. Ex.1005, Buchanan at

2:23-58; Ex.1049, Colombo at p.7. Trimethylaluminum, a precursor used to

deposit aluminum films, was known to be highly pyrophoric and to thus present

practical difficulties in handling. Ex.1007, Ott at p.6.

62. Before 2001, metal dialkylamides, a type of metal amide, were used in

ALD applications and were known to exhibit a number of desirable characteristics

for ALD precursors. As discussed above, metal dialkylamides had been used

previously to form metal films, including metal oxide films, by CVD. See supra

¶39. For example, titanium dialkylamides (which contain a titanium atom bound

MICRON Ex.1003 p.36


34

to a nitrogen atom, where the nitrogen atom is bound to two alkyl groups) were

used to grow titanium-silicon-nitride and titanium nitride films by ALD. Ex.1018,

Min at p.7; Ex.1010, Leskelä II at p.26. Self-limiting ALD was achieved using a

titanium dialkylamide precursor by adjustment and optimization of deposition

conditions. Ex.1018, Min at p.7.

63. The characteristics of metal alkylamides7 have been known since as

far back as the 1960s. Ex.1039, 518 Patent at 1:61-2:6. At that time, metal

alkylamides came to attention as examples of metal-organic compounds wherein

the metal was bonded to alkylamino groups. Ex.1038, Bradley I at p.7. Early

7 I note here that in the nomenclature of metal alkylamide precursors, the suffixes

“amino” and “amido” are used interchangeably, which is confirmed both in the art

and Harvard’s complaint against Micron in district court litigation involving the

539 Patent. For example, Ti[N(C2H5CH3]4 may be referred to as

tetrakis(ethylmethylamino) titanium or tetrakis(ethylmethylamido) titanium.

Compare Ex.1018, Min at p.7 with Ex.1019, Bouman at p.10; see also, e.g.,

Ex.1020, Harvard Complaint, Case No. 1:16-cv-11249, ¶35 (referring to

“tetrakis(ethyl-methylamino) zirconium” as having an “amido group selected from

the group consisting of dialkylamido, disilylamido and (alkyl)(sily[l]) amido

moieties”) (emphasis added).

MICRON Ex.1003 p.37


35

characterizations of metal dialkylamides found them to be volatile, thermally

stable, and highly reactive. Id. at p.8; Ex.1050, Bradley II at p.5; Ex.1012, Ruff8 at

p.6; Ex.1013, Jones & Lappert at p.23. Further, metal dialkylamides’ reactivity,

volatility, and ability to be vaporized without thermal decomposition were

confirmed in the 1990s. Ex.1008, Vaartstra at 4:65-5:12, 5:54-57; Ex.1032, Fix at

pp.6-7. Thus, before the application for the 539 Patent was filed in 2001, one of

ordinary skill in the art would have been aware that metal alkylamides exhibit

characteristics desirable for ALD. One of ordinary skill in the art would also have

been aware that metal dialkylamides had been described as mitigating carbon

contamination in deposited films. See, e.g., Ex.1021, Shin at pp.1, 6; Ex.1051, Lee

at pp.11, 14.

64. Prior to the filing of the provisional applications to which the 539

Patent claims priority, the same metal precursor frequently was used to form both a

metal oxide and a metal nitride film in both ALD and CVD processes. For

example, trimethylaluminum, Al(CH3)3 (“TMA”), was used to form both Al2O3

(aluminum oxide) and AlN (aluminum nitride). Ex.1015, George I at p.6

(describing uses of Al(CH3)3 as a precursor in Scheme 1). As another example,

8 Hexakis(dimethylamido) dialuminum is a dimer; the compound described in

Ruff, Al[N(CH3)2]3, is the monomeric form of this compound.

MICRON Ex.1003 p.38


36

tetrakis(diethylamino) zirconium, a metal dialkylamide, was used to form both

Zr3N4 (zirconium nitride) and ZrO2 (zirconium oxide). Ex.1016, Bastianini at p.17

(reporting the use of Zr(NEt2)4, “which had already been successfully employed in

the CVD growth of Zr3N4 [a nitride] in the presence of NH3” for deposition of

ZrO2 (an oxide)). See also, e.g., Ex.1005, Buchanan at 20:7-24 (describing the use

of a “zirconium-containing precursor” and “hafnium-containing precursor” in a

process to deposit either a metal oxide or a metal nitride, depending on whether an

oxidant or a nitriding reactant is used); Ex.1009, Leskelä I at pp.21, 25 (describing

metal chlorides as having been used as precursors to make both oxide films and

nitride films); Ex.1010, Leskelä II at p.18 (“Metal halides, especially chlorides, are

applicable precursors in ALD deposition of oxide, sulfide and nitride films.”),

pp.25-28 at Table 1 (showing a variety of precursors that were used as precursors

in ALD processes to form both oxide and nitride film materials).

5. ALD to Deposit Films As Device Dimensions Decreased

65. Metal oxides are a key component of semiconductor devices. For

example, metal oxides can act as conducting oxides (such as tin oxide), or as

electrical insulators (such as aluminum oxide). ALD of metal oxides in

semiconductor devices was being explored before 2001, including as a result of

decreasing device dimensions according to Moore’s Law.

MICRON Ex.1003 p.39


37

66. Moore’s Law is an historical observation that predicts market demand

for functionality on a semiconductor device. Specifically, Moore’s Law predicts

that the number of components on a semiconductor chip will double approximately

every eighteen months. Ex.1052, ITRS Roadmap at p.2. Moore’s Law was

historically observed by those in the semiconductor device field to correctly predict

the increases that actually occurred in semiconductor functionality in the period

between approximately 1970 and 2000. Id.; see also Ex.1044, Ritala II at p.7.

67. As device dimensions decreased consistent with Moore’s Law prior to

2001, the need for highly conformal films of uniform thickness was recognized

more and more by those in the art. See, e.g., Ex.1005, Buchanan at 1:15-17 (“As

dimensions of semiconductor devices shrink to improve performance, the need to

control film thickness to thinner and thinner uniform dimensions increases.”). For

example, it was recognized that precise and tight control over film thickness would

be necessary to precisely control gate tunneling leakage, which has a strong

(exponential) dependence on a film’s thickness. Because those in the field

recognized that creating films of precisely controlled thickness would be an

important factor going forward in semiconductor devices, in order to accommodate

the scaling in accordance with Moore’s Law that was predicted, it was recognized

that ALD was a particularly attractive deposition technique because it provides

precise thickness control and the ability to form extremely thin layers. Ex.1042,

MICRON Ex.1003 p.40


38

SST at pp.6-7 (noting the need to shift from polysilicon-insulator-silicon structures

to metal-insulator-metal structures, explaining as follows: “‘The gate stack must be

integrated in the (n and p) MOS transistor, with the possibility to down-scale the

stack to 0.5nm EOT.’ Their work points to ALCVD as the solution. . . . ‘ALCVD

results in perfect thickness and uniformity, as well as composition control over

large substrates.’”); Ex.1044, Ritala II at p.7 (noting that the characteristics of

ALD, including the ability to achieve self-limiting reactions, large-area uniformity

and conformality, and control over film thickness “make ALD an important film

deposition technique for future microelectronics.”); Ex.1035, Suntola II at p.8

(describing ALD as a process that can form thin metal oxide films of high

dielectric strength over a large area); Ex.1046, Ritala III at pp.10-11 (examining

ALD to form high permittivity dielectric thin films, noting that using ALD for this

process allows “a low temperature deposition of novel dielectrics with high

permittivities and low leakage current densities” with large area uniformity and the

ability to scale to large area applications).

68. ALD processes to deposit metal oxides such as Al2O3 were developed

particularly for coverage of “very-high-aspect-ratio features.” Ex.1042, SST at p.7

(“Genus also sees an atomic layer process as the answer for high-k dielectrics. It

has developed a process for Al2O3 that provides atomically uniform films with

100% step coverage on very-high-aspect-ratio features.”). High aspect ratio

MICRON Ex.1003 p.41


39

features such as trenches, pores and stacks were increasingly used throughout the

1990s to increase semiconductor device capacity as device size continued to

shrink. Ex.1052, ITRS Roadmap at pp.4 (describing the need for a high-dielectric

constant replacement material due to “aggressive scaling” in DRAM, as well as a

new fabrication process for stack or trench capacitor structures), 5 (“As a result of

ground-rule shrinking, the aspect ratio (trench depth to trench width) will increase

up to values of ~60 for the 100 nm technology node.”).

69. Those using ALD to form metal oxides often looked to precursors that

had been successfully used in CVD processes to form metal oxides. For example,

zirconium chloride, a precursor often used to deposit zirconium oxide films by

CVD, was used in ALD processes in the mid-1990s. Ex.1047, Niinistö at p.7;

Ex.1053, Kytökivi at p.5.

B. The 539 Patent

70. The claims of the 539 Patent at issue in this proceeding relate to

processes for forming a metal oxide.

71. As I explained in detail above, by 2001 (the earliest date to which the

539 Patent can claim priority), it had already been recognized that, given the need

for precise thickness control over the very thin films that would need to be formed

in devices given the scaling down, size-wise, of devices in the future, ALD would

be a useful technique to form these very thin films. See supra ¶¶54, 67-68.

MICRON Ex.1003 p.42


40

72. Moreover, as I explained above, it had already been recognized by

2001 that methods to deposit metal-containing thin films using metal chlorides as

precursors in ALD led to undesirable side effects, including the incorporation of

residual chlorine in the deposited film and etching of the growing film or substrate

by chlorine by-products. See supra ¶61.

73. The 539 Patent purports to provide a solution to these recognized

problems by proposing the use of “chlorine-free precursors for CVD or ALD of

metal silicates or oxides.” Ex.1001, 539 Patent at 1:64-65.

74. While the specification of the 539 Patent states that a feature of the

alleged invention is that it permits deposition of materials “by a CVD process in

which all the reactants may be mixed homogeneously before delivery to the heated

surface of the substrate,” id. at 2:20-23, claim 31 of the 539 Patent claims a process

for forming a metal oxide that requires alternately exposing a heated surface to the

vapor of one or more metal amides having a certain chemical structure and then to

the vapors of water or an alcohol. Id. at 32:17-40.

75. The process recited in claim 31 of the 539 Patent clearly recites ALD.

For example, claim 24 of the 539 Patent (from which claim 31 depends) requires

that the following steps occur in the claimed method of forming a metal oxide:

“exposing a heated surface alternately to the vapor of one or more

metal amides having an amido group selected from the group

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consisting of dialkylamido, disilyamido and (alkyl)(silyl) amido

moieties,

and then to the vapors of water or an alcohol.”

Id. at 32:18-22 (emphasis added). The 539 Patent’s specification uses similar

language to describe ALD. Id. at 21:30-33 (“Alternating layers of first and second

reactant components are introduced into the deposition chamber and deposited on

the substrate to form a layer of controlled composition and thickness.”) (emphasis

added). Thus, it is clear that claim 31 is claiming an ALD process.

76. The 539 Patent further purports to solve the problems caused by use

of chlorine-containing precursors in deposition processes by replacing such

precursors with metal alkylamides. For example, the 539 Patent suggests that

hafnium oxide may be formed by ALD using tetrakis(dimethylamido) hafnium as a

metal precursor. Id. at 19:58-60. The 539 Patent further lists exemplary metal

amides in Table 1, which exemplary metal amides include tin dialkylamides (such

as tetrakis(diethylamido) tin (Sn(NEt2)4) and tetrakis(dimethylamido) tin

(Sn(NMe2)4)) and aluminum dialkylamides (such as hexakis(diethylamido)

dialuminum (Al2(NEt2)6) and hexakis(dimethylamido) dialuminum (Al2(NMe2)6)).

Id. at Table 1. The 539 Patent further claims that one type of exemplary metal

amide, tetrakis(alkylamido) hafnium compounds, can provide “highly uniform

films of hafnium oxide even in holes with very high aspect rations [sp] (over 40),”

MICRON Ex.1003 p.44


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a process in which hafnium chloride and hafnium tetra-tert-butoxide had been less

successful. Id. at 20:4-11. The 539 Patent’s statements regarding deposition in

holes with high aspect ratios are specific to formation of hafnium oxide and do not

describe any other metal oxide or metal precursor. Id.

77. Accordingly, the 539 Patent claims simply recite already known ALD

deposition methods to form metal oxides by claiming specific metal alkylamides

and oxidants as precursors in the ALD process.

VI. 539 PATENT PROSECUTION HISTORY

A. Prosecution of 539 Patent

78. I have reviewed the prosecution history of the 539 Patent.

79. The application that led to the issuance of the 539 Patent was

originally filed with 32 claims. Ex.1002, 539 Patent FH at pp.44-49.

80. I focus here on the claims-at-issue in this Petition. For reference, and

for the claims-at-issue here, original claim 28 corresponds to claim 24 (from which

Claim 31 depends) as issued. I understand that issued claim 31 was not included in

the original application for the 539 Patent, but was added during prosecution of the

539 Patent as claim 35. Id. at p.68.

81. On September 1, 2004, original claim 28 and later-added claim 35

were rejected by the Patent Office Examiner for being indefinite under the second

paragraph of 35 U.S.C. § 112. Id. at p.78. The Examiner further rejected original

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43

claim 28 and later-added claim 35 as being obvious over U.S. Pat. No. 6,395,209

(Yoshida) in view of U.S. Pat. No. 4,723,978 (Clogdo). Id. at pp.79-80. In this

rejection, the Examiner found that Yoshida disclosed a method for depositing a

metal oxide film using organic precursor materials, but did not teach using an

alkoxysilanol. The Examiner found that Clogdo disclosed a method of forming an

inorganic material utilizing an organoalkoxysilanol, and that it would have been

obvious to one of ordinary skill in the art to use Clogdo’s organoalkoxysilanol

precursor in Yoshida’s method to deposit a metal oxide. Id. at p.79.

82. On March 1, 2005, Applicant amended claim 35 to “correct

typographical errors or to clarify the invention.” Id. at p. 94.9 In response to the

Examiner’s obviousness rejection, Applicant argued that neither Yoshida nor

Clodgo teaches vapor deposition processes using metal amide vapors. Id. at p.98.

83. On April 12, 2005, the Examiner allowed original claim and later-

added claim 35 to issue. The Examiner’s notice of allowance did not include any

further discussion of the Examiner’s reasons for allowing these claim or discussion

of Applicant’s arguments against the Examiner’s rejections. Id. at p.105.

9 It is not clear from this statement or the 539 Patent’s file history whether the

amendment of claim 35 was done in order to correct a typographical error, or if it

was done rather “to clarify the invention.”

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B. Prosecution of U.S. Patent No. 8,334,016

84. I understand that U.S. Pat. No. 8,334,016 (“016 Patent”) is a

continuation of U.S. Pat. No. 7,507,848 (“848 Patent”). Ex.1026, 016 Patent. I

further understand that the 848 Patent is a continuation of the 539 Patent. Id.

Thus, I have also reviewed portions of the prosecution history of the 016 Patent as

it relates to this IPR petition.

85. I understand that the Vaartstra prior art reference described herein,

and which forms the basis for some of my invalidity opinions in this declaration,

was discussed during prosecution of the 016 Patent. Ex.1014, 016 FH at pp.3-5. I

further understand that Vaartstra and another reference, Aarik, were the basis for

an obviousness rejection of the claims of the 016 Patent. Id.

86. In response to the Examiner’s rejection of the 016 Patent’s claims

based on the Vaartstra reference, Applicant amended the claims to include a

limitation specifying that the depositions of the first and second reactant

components are “self-limiting.” Id. at pp.18-19. No such limitation is present in

claim 31 of the 539 Patent.

87. In responding to the Examiner’s rejection based on Vaartstra,

Applicant argued that Vaartstra teaches only CVD, not ALD. Id. at pp.20-23.

However, while Vaartstra does teach CVD rather than ALD, Vaartstra discloses

metal alkylamide precursors that were already known and characterized as having

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properties desirable for ALD. These properties, as I discuss above, include

volatility, an adequate “window” between the temperature at which a compound

evaporates/vaporizes and that at which the compound decomposes, thermal

stability, and reactivity. See supra ¶¶57, 62-63. Thus, it appears that the Examiner

did not appreciate, and was not informed of, this fact during prosecution of the 016

Patent.

88. Furthermore, when allowing the claims of the 016 Patent, the

Examiner referenced a 1999 publication by Min and colleagues. Ex.1014, 016 FH

at pp.40-41. The Examiner stated that the prior art, including Vaartstra and the

1999 Min reference, taught the use of a metal alkylamide to form a titanium-

silicon-nitride film but did not teach or suggest forming a metal oxide by ALD

using metal alkylamides. Id. at p.40. I disagree with the Examiner’s opinion. In

my opinion, and as discussed further below, Vaartstra importantly teaches that the

metal precursors disclosed therein could be used to deposit both an oxide and a

nitride. See Ex.1008, Vaartstra at 11:2-10 (stating that “the metalloamide vapor”

may be reacted with “either ammonia or hydrazine” to form a multi-metallic

nitride, and further stating that “the metalloamide vapor” may be reacted with

oxygen, nitrous oxide, water vapor or ozone to form a multi-metallic oxide).

Indeed, Vaartstra further makes clear that “the metalloamide compounds are

versatile in that, by appropriate choice of a reactant gas, they can be used to form

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any of metal nitride, oxide, boride, sulfide, etc.-containing multi-metallic layers.”

Id. at 13:51-54.

89. By this disclosure, Vaartstra teaches that a vapor deposition process to

form a nitride using metalloamide compounds may similarly be used to form an

oxide using the same metalloamide compounds. This was well known in the prior

art both for CVD and ALD. See, e.g., Ex.1015, George I at p.6 (Scheme 1, listing

Al(CH3)3 as having been used to form both oxide Al2O3 (an oxide) and AlN (a

nitride); Ex.1008, Leskelä I at pp. 21, 25 (describing metal chlorides as having

been used as precursors to make both oxide films and nitride films); Ex.1010,

Leskelä II at p.18 (“Metal halides, especially chlorides, are applicable precursors in

ALD deposition of oxide, sulfide and nitride films.”), pp.25-27 at Table 1

(showing compounds that were used as precursors in ALD processes to form both

oxide and nitride film materials); Ex.1016, Bastianini at p.17 (reporting the use of

Zr(NEt2)4, “which had already been successfully employed in the CVD growth of

Zr3N4 [a nitride] in the presence of NH3” for deposition of ZrO2 (an oxide)).

VII. CLAIM CONSTRUCTION

90. I understand that in deciding whether to institute inter partes review,

“[a] claim in an unexpired patent shall be given its broadest reasonable

construction in light of the specification of the patent in which it appears.” 37

C.F.R. § 42.100(b). I further understand that “the broader standard serves to

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47

identify ambiguities in the claims that can then be clarified through claim

amendments.” Final Rule, 77 Fed. Reg. 48680, 48699 (Aug. 14, 2012).

91. In forming my opinions as set forth in this declaration, I have

accorded all claims terms in claim 31 of the 539 Patent their broadest reasonable

interpretation, as would be understood by a person of ordinary skill in the art at the

time of the alleged invention of the 539 Patent.

VIII. THE PRIOR ART

A. Csaba Dücsö, et al., Deposition of Tin Oxide into Porous Silicon by Atomic Layer Epitaxy (“Dücsö”)

92. I understand that Dücsö is prior art to the 539 Patent under at least 35

U.S.C. § 102(b), because it was published in February 1996, long before the PCT

application to which the 539 Patent claims priority. The title of Dücsö is

“Deposition of Tin Oxide into Porous Silicon by Atomic Layer Epitaxy.”

93. Dücsö describes an ALD process that deposits a conformal coating of

a metal oxide, specifically tin oxide, onto a porous silicon (“PS”) structure with

extremely high aspect ratio pores. The PS structure on which the tin oxide film is

deposited by ALD in Dücsö has pores that are approximately 2 µm long and

approximately 14 nm in diameter, giving them an aspect ratio of approximately

140:1. Ex.1006, Dücsö at pp.6-7. Such high-aspect ratio PS structures are used to

fabricate various types of integrated circuit structures, including LEDs. Id. at p.6.

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94. As Dücsö explains, physical deposition and electrochemical

deposition methods do not yield sufficiently conformal deposition in pores of high

aspect ratio. Id. However, as Dücsö teaches, “surface controlled layer growth by

atomic layer epitaxy (ALE)” is one of “the most promising techniques available for

conformal coating of the surface in porous single-crystalline materials.” Id.

95. Dücsö then teaches a method for depositing tin oxide in its high-

aspect ratio PS structure. In Dücsö’s method, a tin-containing precursor (tin

tetrachloride, or SnCl4) and water vapor are alternately pulsed into the deposition

chamber, in which the PS substrate has been heated to a temperature between 430

and 545°C. Id. at p.6. In Dücsö’s ALD cycle, the substrate is first exposed to

SnCl4, followed by a purge of the chamber with pure nitrogen gas, followed by

exposure to water vapor, followed by a purge of the chamber with pure nitrogen

gas; this cycle is then repeated to perform a total of 150 cycles to achieve the

desired film thickness. Id. at p.7 (“Based on a previous study the number of cycles

was chosen to be 150 bearing in mind an expected growth rate of 0.35 Å/cycle and

a decreasing pore diam during the process form the initial average of 14 nm to ca.

4 nm.”).10

10 Dücsö cites another study by the same group for additional explanation of its

disclosed ALD process to form tin oxide. Id. at p.6 (citing a 1994 publication by

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96. As Dücsö explains, the conditions for its ALD process were tested and

adjusted “such that chemisorption was the growth rate determining step in the

process,” thus signaling the achievement of self-limiting ALD in the very high-

aspect ratio structure. Id. at p.6; see also id. at pp.9-10 (“With carefully selected

pulse durations for the chemisorption, purge and reaction steps, as well as

appropriately chosen pressure and temperature conditions for ALE, a conformal

coverage of SnOx on PS was achieved in the extreme 140:1 aspect ratio pores.”).

Dücsö further teaches to adjust the pulse duration when performing ALD to

deposit tin oxide in high-aspect ratio structures, because the longer pulse duration

allows more time for the tin precursor to “diffuse into the pores and chemisorb at

the free surface sites.” Id. at p.9. The adjustment of temperature, pressure, and

pulse duration to achieve self-limiting ALD described in Dücsö is consistent with

that which is routinely performed by those of ordinary skill in the art when

depositing films by ALD.

Viirola and Niinistö, explaining that “[t]he SnOx depositions were based on our

previous study.”). In my experience, it is common in peer-reviewed publications

to refer to other articles for further explanation of methods or protocols. Thus, one

of ordinary skill reading Dücsö would have looked to the Viirola and Niinistö

paper cited by Dücsö.

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B. A.W. Ott, et al., Modification of Porous Alumina Membranes Using Al2O3 Atomic Layer Controlled Deposition (“Ott”)

97. I understand that Ott is prior art to the 539 Patent under at least 35

U.S.C. § 102(b), because it was published in March 1997, long before the PCT

application to which the 539 Patent claims priority. The title of Ott is

“Modification of Porous Alumina Membranes Using Al2O3 Atomic Layer

Controlled Deposition.”

98. Ott describes an ALD process that deposits a conformal coating of a

met

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