2-2 - APET - John Oshinowo - Stable Oxide-Free Silicon ...
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APET Co., Ltd. http://www.apet.co.kr, Dr. John Oshinowo (Vice President) and Bob Pagliaro (Director of Technology) Email: [email protected] Cell phone: +49 175 543 5275 Address: Barmbeker Strasse 28 N, 22303 Hamburg (Germany) Advanced Processing Equipment T echnology APET ( TeraDox Wet Clean Process and System) 16 th of April 21 “Stable Oxide-Free Silicon Wafer Surface with Optimized Si-H Terminations using a Novel HF-Last Wet Clean Technology“
Transcript of 2-2 - APET - John Oshinowo - Stable Oxide-Free Silicon ...
2-2 - APET - John Oshinowo - Stable Oxide-Free Silicon Wafer
Surface with Optimized Si-H Terminations using a Novel HF-Last Wet
Clean TechnologyAPET Co., Ltd. http://www.apet.co.kr,
Dr. John Oshinowo (Vice President) and Bob Pagliaro (Director of Technology) Email: [email protected]
Cell phone: +49 175 543 5275 Address: Barmbeker Strasse 28 N, 22303 Hamburg (Germany)
Advanced Processing Equipment Technology
16th of April 21
APET TeraDox Wet Clean Process and System
To provide a pristine, stable oxide-free silicon wafer surface with optimized Si-H terminations using a novel HF last wet clean technology.
What is the purpose for TeraDox System ?
2
• Encapsulated SIMS depth profiles
• XPS – measurements
Results
• The TeraDox technology has proven Si- oxide free surface up to several days
• APET offers high end wet cleaning equipment to achieve the S-oxide free surfaces
APET TeraDox Wet Clean System
3
4
APET headquarter
New APET headquarter with new address (since 09th of February 2021):
APET Ltd., 20, Masan 6-ro, Jinwi-myeon, Pyeongtaek-si, Gyeonggi-do, So
uth Korea, 17716
www.apet.co.kr
APET TeraDox Wet Clean Process and System
5
6
Classical
7
What are the key parameters that affect the native oxide thickness and growth rate
following an HF oxide etch to the bare silicon surface?
Reference: Journal of Applied Physics Vol 68 No.3, 1 August 1990, Morita et al
Fast Si-oxide growth rate in air compared to DI water
Oxide groth rate in waterOxide groth rate in air
APET TeraDox Wet Clean Process and System
8
APET TeraDox Wet Clean Process and System
10
11
Topic of evaluation:
Method for preparing Parts-Per-Trillion level dissolved O2 in UPW using membrane degassifiers to enable
superior wafer surface preparation
3M Separation & Purification Sciences Division, Charlotte, NC (USA)
APET Co., Ltd, Mesa, AZ (USA)
R. Pagliaro Jr.
12
Robot
FOUP
Process
Bath
Monitor
Exhaust
FOUP
Robot
Electric
D I w
APET TeraDox Wet Clean System
Example of an APET 300mm TeraDox system configuration with FOUPS & additional cleans
13
WAFER TRANSFER / DRYER HOOD
OVER THE PROCESS VESSEL
PROCESS VESSEL, CASSETTELESS
WAFER CARRIER & ELEVATOR
OVER THE WAFER CASSETTE DOCK
PHOTOS OF THE PROCESS DECK STATIONS ON A TYPICAL CASSETTELESS 200mm SYSTEM
14
Typical NEO-2000 TeraDox Main Unit Layout
APET TeraDox Wet Clean System
15
HCL Supply
For Hydrophilic Surface Only
Full WET Clean Sequence
16
APET TeraDox Wet Clean Process and System
Is an enhanced version of APET’s NEO FRD system which integrates dHF etching, insitu-rinsing and a world class drying technology into a single vessel wet processor (“dry in / dry out”) for wafers and other substrates.
The enhancements that are incorporated on the APET FRD tool platforms include the five patented “oxide free” methods and system features which provide some of the world’s best wet process capabilities.
The Dox60 DI water degas unit is a stand-alone module that is paired in series with the TeraDox main wet process unit.
System design optimization, maximizing the purity of the wet process chemistry and minimizing permeation are critical parameters for achieving the TeraDox’s superior “oxide free” process capabilities.
Continuous improvement efforts have produced innovations for new system features and options such as chemical degassing, dHCl, dNH4OH & UHP DIO3 chemistries, heated & ionized N2 only drying.
System is available with semi-automated & fully-automated wafer handling (including SMIF & FOUP), cassette & cassetteless configurations, and process vessels for batches of 3, 25 or 50 of 100-300mm diameter wafers.
Recirculating Filtered Etch Bath (RFEB) style system with the TeraDox capabilities is available for R&D and low volume manufacturing applications.
What is the TeraDox System ?
17
H2SO4
HF
HCL
NH4OH
H2O2
O3
N2
IPA
DIW
** DHF and/or DHCL are used based on surface to be Cleaned
Typical Full WET Clean Sequence
**
Flow
18
Physical investigations and study of Si-surface morphology
19
• XPS – measurements
Description SiOx
Thickness() SiOx
Typical Native Oxide 7 2.0 1.50E+15 100% / 0%
Detection Limit of XPS 0.1 0.029 2.10E+13 2.9% / 97.1%
Detection Limit of SIMS 0.0005 0.00014 1.00E+11 0.014% / 99.986%
Assume the silicon wafer surface is terminated with either SiOx or SiHx species
Oxygen Hydrogen
Wafer surface 100%
20
unprocessed control DO= 1 ppb DO= 0.1 ppb *
* The detection limit of this DO meter was O.1ppb (current DO meters can now detect down to 10 ppt)
7.267 E15 at/cm2 2.078 E13 at/cm2 2.627 E12 at/cm2
Results for the effect of DO concentration in the UPW vs. encapsulated SIMS AOD
APET TeraDox Wet Clean Process
… as it can be seen, a lower DO in the UPW allows for a lower AOD
21
Slides 16 & 17 show encapsulated SIMS profiles in the Center and Edge (10mm) of three 200mm wafers using an the APET TeraDox system dHF last wet clean with three different queue times: < 1hr, 3 hrs. and 8 hrs.
- the wafers were dried with heated N2 only (no IPA)
- the oxygen peaks were non-detectable (< 1 E11 at/cm^2) on all three
wafers for the center and edge
Slide 18 shows encapsulated SIMS profiles in the Center and Edge (10mm) of a 200mm wafer using the customer’s dHF last wet clean process of record on competitor’s single wafer wet process system with a queue time of < 1 hr.
- the oxygen peaks > 1 E13 at/cm^2
- the edge (10mm) AOD ~3x higher than the center
Customer demo: encapsulated SIMS depth profiling results measuring oxygen for the APET TeraDox vs customer process of record dHF last
wet process using the “ASM 650 No Bake SiH4 deposition” epi cap recipe
APET TeraDox Wet Clean Process
22
O
DEPTH (Å)
O C
O N
C E
N T
R A
T IO
CF957_YR_16 Slot 25 ID D65603-09 Wf 12 PBL Spree (O)
Analog Devices Inc: Slot 25 ID D65603.09 Wf 12 PBL Spree (O)
O
1E+15
1E+16
1E+17
1E+18
1E+19
1E+20
1E+21
1E+22
0 20 40 60 80 100 120 140 160 180 200
DEPTH (nm)
O C
O N
C E
N T
R A
T IO
O
2/16/2011
CM639_YA_04 Devices Slot 25 ID D65603-09 Wf12 PBL Spree, edge (O)
Analog Devices Slot 25 ID D65603.09 Wf12 PBL Spree, edge (O)
Encapsulated SIMS depth profiles measuring oxygen for the APET TeraDox system dHF last wet clean with a queue time of 8 hrs.
Center Edge
23
An ideal in-line measurement method/system to assess the quality of “as
processed” bare semiconductor wafer surfaces should provide these features and
capabilities:
Nondestructive & noncontact (e.g. PL & m-PCD)
Meaningful and quantitative parameter (atom density, lifetimes, SRV etc.)
Sensitive & accurate
Simple to use
After researching the details for all of the measurable semiconductor surface parameters the APET opinion is that Surface Recombination Velocity (SRV) provides the most meaningful and encompassing information since it is sensitive to all impurities and defects that can affect the electrical performance of the semiconductor device structures being fabricated.
A 4-year focused effort to find the ideal method/system to measure SRV led APET to Q-LIC in 2017, which was invented and developed by the University of Toronto’s CADIPT department.
24
25
The statistical distributions of pixel numbers of the five SRV images clearly show how the SRV changes with queue time.
SRV values increased with Q-time as the native oxide layer grew on the silicon surfaces due to adsorption/absorption of impurities from air exposure.
Case study: SRV evolution vs. queue time (Q-time)
Appl. Phys. Lett. 112, 012105 (2018)
26
Case study: SRV evolution vs. queue time (Q-time) for various treatments
Sample Apparatus DO level
No. 5 APET 40 ppt
No. 6 R&D > 2ppm
No. 7 None N/A
Nos. 12 R&D 2% HF > 2 ppm
1 10 10
Time after etching (hrs)
The APET vs. the other wet processes/systems evaluated clearly demonstrates a
significantly lower number of the recombination centers/defects on the surface. Appl. Phys. Lett. 112, 012105 (2018)
Anti-scrap features to prevent wafer breakage Integrated chemical degassing using membrane contactor technology
Fully integrated filtration and purification of the DI water and N2
Hot N2 wafer drying to minimize organic residues on the wafer surface
Second chemical supply network to complement the HF (option)
Po ionizer to neutralize electrostatic charge on the wafer surface (option)
Catalytic resin module for reducing H2O2 to < 1ppb (option)
Mini-bulk chemical delivery module for chemical supplies (option)
APET TeraDox Wet Clean System
Additional System Features and Options
27
APET TeraDox Endorsement
“ Based on my 40 years of experience with research and development of semiconductor characterization technologies and their applications, along with the APET vs. the competition studies that we have done over the past two years, I think that the APET TeraDox process technology outperforms other wet surface preparation technologies towards producing pristine bare silicon surfaces by large multiples. While there are several critical and enabling components to the APET’s outstanding performance it is primarily achieved by being able to provide DO levels in the process chemistry from at least ~25 times lower (with a resulting threefold decrease in surface recombination velocities) to up to ~50,000 times (with a resulting tenfold decrease in surface recombination velocities) over other established wet cleans.”
Andreas Mandelis, FRSC, FCAE, FAPS, FSPIE, FAAAS, FASME, PhD Professor and Canada Research Chair (Tier 1) Director, Center for Advanced Diffusion-Wave and Photoacoustic Technologies Dept. of Mechanical and Industrial Engineering Dept. of Electrical and Computer Engineering Institute of Biomaterials and Biomedical Engineering University of Toronto 5 King's College Road Toronto, ON M5S 3G8 CANADA
28
Final Comments
The TeraDox technology has proven to be capable to achieve the current
and future stringent requirements for semiconductor wafer surface
preparation.
APET offers unique flexibility (not a cookie cutter approach) to customize a
system (hardware, software and process) to satisfy each customer’s
particular needs.
APET offers high end wet cleaning equipment for our worldwide End-users
base and provides excellent technical support required by a global
equipment supplier.
Thank you!
29
For further information please visit our website: www. apet.co.kr
and/or contact me directly:
Dr. John Oshinowo (Germany)
30
Dr. John Oshinowo (Vice President) and Bob Pagliaro (Director of Technology) Email: [email protected]
Cell phone: +49 175 543 5275 Address: Barmbeker Strasse 28 N, 22303 Hamburg (Germany)
Advanced Processing Equipment Technology
16th of April 21
APET TeraDox Wet Clean Process and System
To provide a pristine, stable oxide-free silicon wafer surface with optimized Si-H terminations using a novel HF last wet clean technology.
What is the purpose for TeraDox System ?
2
• Encapsulated SIMS depth profiles
• XPS – measurements
Results
• The TeraDox technology has proven Si- oxide free surface up to several days
• APET offers high end wet cleaning equipment to achieve the S-oxide free surfaces
APET TeraDox Wet Clean System
3
4
APET headquarter
New APET headquarter with new address (since 09th of February 2021):
APET Ltd., 20, Masan 6-ro, Jinwi-myeon, Pyeongtaek-si, Gyeonggi-do, So
uth Korea, 17716
www.apet.co.kr
APET TeraDox Wet Clean Process and System
5
6
Classical
7
What are the key parameters that affect the native oxide thickness and growth rate
following an HF oxide etch to the bare silicon surface?
Reference: Journal of Applied Physics Vol 68 No.3, 1 August 1990, Morita et al
Fast Si-oxide growth rate in air compared to DI water
Oxide groth rate in waterOxide groth rate in air
APET TeraDox Wet Clean Process and System
8
APET TeraDox Wet Clean Process and System
10
11
Topic of evaluation:
Method for preparing Parts-Per-Trillion level dissolved O2 in UPW using membrane degassifiers to enable
superior wafer surface preparation
3M Separation & Purification Sciences Division, Charlotte, NC (USA)
APET Co., Ltd, Mesa, AZ (USA)
R. Pagliaro Jr.
12
Robot
FOUP
Process
Bath
Monitor
Exhaust
FOUP
Robot
Electric
D I w
APET TeraDox Wet Clean System
Example of an APET 300mm TeraDox system configuration with FOUPS & additional cleans
13
WAFER TRANSFER / DRYER HOOD
OVER THE PROCESS VESSEL
PROCESS VESSEL, CASSETTELESS
WAFER CARRIER & ELEVATOR
OVER THE WAFER CASSETTE DOCK
PHOTOS OF THE PROCESS DECK STATIONS ON A TYPICAL CASSETTELESS 200mm SYSTEM
14
Typical NEO-2000 TeraDox Main Unit Layout
APET TeraDox Wet Clean System
15
HCL Supply
For Hydrophilic Surface Only
Full WET Clean Sequence
16
APET TeraDox Wet Clean Process and System
Is an enhanced version of APET’s NEO FRD system which integrates dHF etching, insitu-rinsing and a world class drying technology into a single vessel wet processor (“dry in / dry out”) for wafers and other substrates.
The enhancements that are incorporated on the APET FRD tool platforms include the five patented “oxide free” methods and system features which provide some of the world’s best wet process capabilities.
The Dox60 DI water degas unit is a stand-alone module that is paired in series with the TeraDox main wet process unit.
System design optimization, maximizing the purity of the wet process chemistry and minimizing permeation are critical parameters for achieving the TeraDox’s superior “oxide free” process capabilities.
Continuous improvement efforts have produced innovations for new system features and options such as chemical degassing, dHCl, dNH4OH & UHP DIO3 chemistries, heated & ionized N2 only drying.
System is available with semi-automated & fully-automated wafer handling (including SMIF & FOUP), cassette & cassetteless configurations, and process vessels for batches of 3, 25 or 50 of 100-300mm diameter wafers.
Recirculating Filtered Etch Bath (RFEB) style system with the TeraDox capabilities is available for R&D and low volume manufacturing applications.
What is the TeraDox System ?
17
H2SO4
HF
HCL
NH4OH
H2O2
O3
N2
IPA
DIW
** DHF and/or DHCL are used based on surface to be Cleaned
Typical Full WET Clean Sequence
**
Flow
18
Physical investigations and study of Si-surface morphology
19
• XPS – measurements
Description SiOx
Thickness() SiOx
Typical Native Oxide 7 2.0 1.50E+15 100% / 0%
Detection Limit of XPS 0.1 0.029 2.10E+13 2.9% / 97.1%
Detection Limit of SIMS 0.0005 0.00014 1.00E+11 0.014% / 99.986%
Assume the silicon wafer surface is terminated with either SiOx or SiHx species
Oxygen Hydrogen
Wafer surface 100%
20
unprocessed control DO= 1 ppb DO= 0.1 ppb *
* The detection limit of this DO meter was O.1ppb (current DO meters can now detect down to 10 ppt)
7.267 E15 at/cm2 2.078 E13 at/cm2 2.627 E12 at/cm2
Results for the effect of DO concentration in the UPW vs. encapsulated SIMS AOD
APET TeraDox Wet Clean Process
… as it can be seen, a lower DO in the UPW allows for a lower AOD
21
Slides 16 & 17 show encapsulated SIMS profiles in the Center and Edge (10mm) of three 200mm wafers using an the APET TeraDox system dHF last wet clean with three different queue times: < 1hr, 3 hrs. and 8 hrs.
- the wafers were dried with heated N2 only (no IPA)
- the oxygen peaks were non-detectable (< 1 E11 at/cm^2) on all three
wafers for the center and edge
Slide 18 shows encapsulated SIMS profiles in the Center and Edge (10mm) of a 200mm wafer using the customer’s dHF last wet clean process of record on competitor’s single wafer wet process system with a queue time of < 1 hr.
- the oxygen peaks > 1 E13 at/cm^2
- the edge (10mm) AOD ~3x higher than the center
Customer demo: encapsulated SIMS depth profiling results measuring oxygen for the APET TeraDox vs customer process of record dHF last
wet process using the “ASM 650 No Bake SiH4 deposition” epi cap recipe
APET TeraDox Wet Clean Process
22
O
DEPTH (Å)
O C
O N
C E
N T
R A
T IO
CF957_YR_16 Slot 25 ID D65603-09 Wf 12 PBL Spree (O)
Analog Devices Inc: Slot 25 ID D65603.09 Wf 12 PBL Spree (O)
O
1E+15
1E+16
1E+17
1E+18
1E+19
1E+20
1E+21
1E+22
0 20 40 60 80 100 120 140 160 180 200
DEPTH (nm)
O C
O N
C E
N T
R A
T IO
O
2/16/2011
CM639_YA_04 Devices Slot 25 ID D65603-09 Wf12 PBL Spree, edge (O)
Analog Devices Slot 25 ID D65603.09 Wf12 PBL Spree, edge (O)
Encapsulated SIMS depth profiles measuring oxygen for the APET TeraDox system dHF last wet clean with a queue time of 8 hrs.
Center Edge
23
An ideal in-line measurement method/system to assess the quality of “as
processed” bare semiconductor wafer surfaces should provide these features and
capabilities:
Nondestructive & noncontact (e.g. PL & m-PCD)
Meaningful and quantitative parameter (atom density, lifetimes, SRV etc.)
Sensitive & accurate
Simple to use
After researching the details for all of the measurable semiconductor surface parameters the APET opinion is that Surface Recombination Velocity (SRV) provides the most meaningful and encompassing information since it is sensitive to all impurities and defects that can affect the electrical performance of the semiconductor device structures being fabricated.
A 4-year focused effort to find the ideal method/system to measure SRV led APET to Q-LIC in 2017, which was invented and developed by the University of Toronto’s CADIPT department.
24
25
The statistical distributions of pixel numbers of the five SRV images clearly show how the SRV changes with queue time.
SRV values increased with Q-time as the native oxide layer grew on the silicon surfaces due to adsorption/absorption of impurities from air exposure.
Case study: SRV evolution vs. queue time (Q-time)
Appl. Phys. Lett. 112, 012105 (2018)
26
Case study: SRV evolution vs. queue time (Q-time) for various treatments
Sample Apparatus DO level
No. 5 APET 40 ppt
No. 6 R&D > 2ppm
No. 7 None N/A
Nos. 12 R&D 2% HF > 2 ppm
1 10 10
Time after etching (hrs)
The APET vs. the other wet processes/systems evaluated clearly demonstrates a
significantly lower number of the recombination centers/defects on the surface. Appl. Phys. Lett. 112, 012105 (2018)
Anti-scrap features to prevent wafer breakage Integrated chemical degassing using membrane contactor technology
Fully integrated filtration and purification of the DI water and N2
Hot N2 wafer drying to minimize organic residues on the wafer surface
Second chemical supply network to complement the HF (option)
Po ionizer to neutralize electrostatic charge on the wafer surface (option)
Catalytic resin module for reducing H2O2 to < 1ppb (option)
Mini-bulk chemical delivery module for chemical supplies (option)
APET TeraDox Wet Clean System
Additional System Features and Options
27
APET TeraDox Endorsement
“ Based on my 40 years of experience with research and development of semiconductor characterization technologies and their applications, along with the APET vs. the competition studies that we have done over the past two years, I think that the APET TeraDox process technology outperforms other wet surface preparation technologies towards producing pristine bare silicon surfaces by large multiples. While there are several critical and enabling components to the APET’s outstanding performance it is primarily achieved by being able to provide DO levels in the process chemistry from at least ~25 times lower (with a resulting threefold decrease in surface recombination velocities) to up to ~50,000 times (with a resulting tenfold decrease in surface recombination velocities) over other established wet cleans.”
Andreas Mandelis, FRSC, FCAE, FAPS, FSPIE, FAAAS, FASME, PhD Professor and Canada Research Chair (Tier 1) Director, Center for Advanced Diffusion-Wave and Photoacoustic Technologies Dept. of Mechanical and Industrial Engineering Dept. of Electrical and Computer Engineering Institute of Biomaterials and Biomedical Engineering University of Toronto 5 King's College Road Toronto, ON M5S 3G8 CANADA
28
Final Comments
The TeraDox technology has proven to be capable to achieve the current
and future stringent requirements for semiconductor wafer surface
preparation.
APET offers unique flexibility (not a cookie cutter approach) to customize a
system (hardware, software and process) to satisfy each customer’s
particular needs.
APET offers high end wet cleaning equipment for our worldwide End-users
base and provides excellent technical support required by a global
equipment supplier.
Thank you!
29
For further information please visit our website: www. apet.co.kr
and/or contact me directly:
Dr. John Oshinowo (Germany)
30
