Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V...

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Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor Industry Comparison of SIA Technology Road Map

Transcript of Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V...

Page 1: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Overview of Semiconductor Technologies

• Key Semiconductor Technologies:- Bulk silicon, SOI, III-V and II-VI semiconductors

• Economic Impacts of Semiconductor Industry

• Comparison of SIA Technology Road Map

Page 2: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Economic Impact of Semiconductor Industry

• Global S.I. growth rate at 15%/year reaching $140 B in 97. This could reach to $300 B by early 2000 due to the strong demand of communications equipment and computers.

• S.I. growth holds down inflation: S.I. price index: -4.5%/yr vs. +3%/yr for the rest of economy.

• Higher wages and lower inflation.

• Faster technology diffusion (25%): Auto:60 yrs, Tel:35, TV:25, PC:13, Internet:< 10 yrs.

• Drivers of semiconductor market growth: declining prices and increasing performance: price/DRAM bit reduced by 25 to 30%/yr, while IC complexity double every 18 months (Moore’s Law).

• Less’s Law: improvements in reliability have accompanied increases in chip complexity:transistors/die increases from 2x103 in 1971 to 1.5x108 in 2003.

Page 3: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Current Status, Issues, and Trends in Semiconductor Technologies

• Bulk Silicon Technologies:- Scaled down submicron VLSIs- Larger wafer size, 8, 10, 12”.. - Copper interconnects

• Silicon-On-Insulator (SOI) technologies:- SIMOX and wafer bonding (WB).- low power, low voltage, high-speed, and high density ULSIs. 3-

D IC’s

• III-V Semiconductor Technologies.- LEDs, LDs, detectors, MESFETS, HBTs, HEMTs, quantum effect devices (QWIPs). - photovoltaic devices (solar cells) technology- wide band gap and high temperature devices

(InGaN, GaN, AlGaN, SiC, diamond)

Page 4: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Comparison of the World Semiconductor Industry

Page 5: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Comparison of SIA Technology Node Introduction Projections in 94 vs. 97

94’ Roadmap 98 01 04 07 10 97”Roadmap 97 99 03 06 09

Min feature(m) 0.25 0.18 0.13 0.10 0.07

Lithography 248nm 248/193 193 EUV EUV?

DRAM bits/chip 256M 1G 4G 16G 64G

P xstrs/chip 28M 64M 150M 350M 800M

P xstrs/cm2 7M 13M 25M 50M 90M

New Materials for the New Millennium:

• Cu- metallization replaces Al-Cu interconnects for Si IC’s.

• New dielectric materials such as Ta2O5, BaSrTiO3 are being investigated to

replace SiO2, Si3N4 to handle the increase of DRAM density.

• New SOI technology to replace bulk Si technology for higher packing density,

higher speed and lower power consumption.

Page 6: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Technology Road Map for Semiconductors

Page 7: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Delay Time vs. Power Dissipation for CMOS and Other Devices

Page 8: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Exponential Increase of DRAM Density vs. Year(Based on SIA Road Map)

Page 9: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Microprocessor Computational Power vs. Year

Page 10: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Silicon-On-Insulator (SOI) Technologies

• Separation by Implantation of Oxygen (SIMOX) Process.

• Wafer Bonding (WB) Process.

• SIMOX WB Process.

• Zone Melting Recrystallization (ZMR) Process

• Epitaxial Lateral Overgrowth (ELO) Process

• Fully Isolation of Porous Silicon (FIPOS) Process

Page 11: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Photovoltaic (PV) Market Analysis

• PV Market Growth Rate:Solar cell module production average increase: 14% per year 90-97, and

production jumped by 38% in 1997 to 122 MWp. Growth rate is expected to increase at a rate of 20%/year over the next 15 years with potential annual module shipments of around 1,600 MWp (about $3billions per year by 2010) in the year 2010.

• PV Markets:- consumer electronic products (14%): calculators, watches, and lanterns...

- off-grid residential power systems (35%): cottages, rural village homes..

- off-grid industrial power system (33%) : telecom.repeaters..

- off-grid connected PV systems(18%):government and/or utility demons.

Page 12: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Key PV Technologies

• Single crystal Si solar cells.

• Poly Si solar cells.

• a- Si thin film solar cells.

• Ribbon Si solar cells.

• CdTe thin film solar cells.

• CIS (CuInSe) thin film solar cells.

• III-V semiconductor (GaAs, InP, GaInP..) solar cells

- single and multi-junction solar cells

• Concentrator solar cells.

Page 13: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

III-V Semiconductor Technologies

•High-speed, high-frequency, quantum effect, and optoelectronic devices:

- HBTs, HEMTs, MESFETs.

- Quantum dot, quantum wire, and quantum well infrared

photodetectors and lasers. Superlattice heterostructure devices

- LEDs, LDs, solar cells.

•III-V materials:- GaAs/AlGaAs, InGaAs/GaAs, InGaAs/AlGaAs grown on GaAs

- InGaAs/InAlAs, InGaAsP/InP grown on InP

- InP, InAs, InSb, InGaSb, GaInN, GaN, AlN

Page 14: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

II-VI and Wide Band Gap Semiconductors

•II-VI semiconductors:- ZnSe, ZnS, CdS, CdTe: Solar cells, LEDs, LDs

- HgCdTe, CdZnTe, PbSnTe.

•Wide Band Gap Semiconductors: ( 2.5 < Eg < 6.5 eV)

- Diamond, SiC, AlN, GaN, AlGaN: high-temperature transistors (HBTs, MESFETS..), high- power devices, UV detectors and laser diodes.

Page 15: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.
Page 16: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

A Bright Future for Blue/Green LEDs(Highly luminous III-V nitride based LEDs)

Color Wavelength (nm)

Violet < 430

Blue 430 - 490(GaN,InGaN/AlGaN LEDs)

Green 490 - 560(InGaN/AlGaN or ZnSe, GaP LED)

Yellow 560 - 590(AlInGaP LEDs)

Orange 590 - 630

Red > 630(AlGaAs LEDs)

Page 17: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Chapter 1 Classification of Solids

• The Crystal Systems and Bravais Lattices.

• The Crystal Structure and The Unit Cell.

• Miller Indices and Crystal Planes.

• The Reciprocal Lattice and Brillouin Zone.

• Types of Crystal Bindings

• Defects in Crystalline Solids

Page 18: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Classification of Solids

Based on geometrical aspects:- 7 crystal systems and 14 Bravais lattices

• Based on binding energy:

- metallic, ionic, covalent, and molecular crystals

Na, K; NaCl; C, Si, Ge; Ar, He, Ne

• Based on electrical conductivity: metals, semiconductors, insulators.- metals : > 104; semiconductors: 10-4 << 104; insulators: < 10-5 (ohm-cm)-1

• Based on atomic arrangements (periodicity):- single crystalline solids: atomic arrangements are ordered with periocity

extending through the entire crystal lattice.

- polycrystalline solids: short range ordered within grain and separated by grain

boundaries.

- amorphous solids: no short range ordered, atomic arrangements are highly

irregular. (glass, oxides,…)

Page 19: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Bravais Lattices

Seven lattice systems and fourteen Bravais lattices• Triclinic b1 b2 b3 simple

• Monoclinic b1 b2 b3 simple, base-centered

= = 90 o • Orthorhombic b1 b2 b3 simple, base-centered

= = = 90 o body-centered; F.C.C• Tetragonal b1 = b2 b3 simple, body-centered

= = = 90 o • Trigonal b1 = b2 = b3 simple,

= = 90 o • Hexagonal b1 = b2 b3 simple,

= = 90 o , • Cubic b1 = b2= b3 simple, body-centered

= = = 90 o F. C. C.

Page 20: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Unit Cell of a Bravais Lattice

Unit Cell of a Bravais Lattice

b1

b2

b3

z

y

x r (n1,n2,n3) = r (0,0,0) + R

is the translational basis vector

R = n1b1 + n2b2+ n3b3

Page 21: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

The Bravais Lattice

• A space lattice is a concept introduced first by Bravais, and hence the Bravais lattice. The various arrangements of unit cells in a crystalline solid can be achieved by means of space lattice.

• A parallelepiped unit cell of a Bravais lattice is formed by 3 non-coplanar basis vectors b1, b2,, and b3 with different lengths and angles between them. There are 14 Bravais lattices in space lattice as shown in Fig.1.1.

• A unit cell formed by 3 non-coplanar primitive basis vectors with lattice points only located in the vertices of the parallelepiped unit cell is called primitive cell.

• The translational basis vector can be used to generated any lattice points in the space lattice, which can be described by:

- r (n1, n2, n3) = r(0, 0, 0) + R

where R = n1b1 + n2b2 + n3b3; n1, n2, n3 = 0, 1, 2, 3……

Page 22: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

The Crystal Structure

• The crystal structure is formed by attaching an atom or

a group of atoms to the lattice point of a Bravais lattice.• Figure 1.3 (a) shows a 2-D space lattice, and Fig.1.3(b)

shows a 2-D crystal structure with atoms attached to each lattice point.

• Four important crystal structures for semiconductors are shown in Fig.1.4. These are: (a) diamond structure (Si, Ge, GaAs), (b) Zinc-blende structure (III-V, II-VI semiconductors), (c)Wurtzite (III-V, II-VI), and

(d) hexagonal closed-packed (HCP) structure.

Page 23: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Miller Indices

• The orientation of a crystal plane can be determined by 3 integers, h, k, l, known as the Miller indices, which are defined by:

hh’ = kk’ = ll’ (1)

where h’, k’, l’, represent the intercepts of a particular plane on the three crystal axes (x,y.z) in units of lattice constant a. h, k, l, are the three smallest integers that satisfy eq.(1).

Example: if h’, k’, l’ = a, 2a, 2a, then the smallest h, k, l

that satisfy eq.(1) is (2,1,1), and the plane is called (211)

plane.

Page 24: Overview of Semiconductor Technologies Key Semiconductor Technologies: - Bulk silicon, SOI, III-V and II-VI semiconductors Economic Impacts of Semiconductor.

Reciprocal Lattices and Brillouin Zone

• The reciprocal lattice is a geometrical construction which allows one to relate the crystal geometry directly to the electronic states and the symmetry properties of a crystal in the reciprocal space. It’s the Fourier transform of the direct (space) lattice in the reciprocal space, which can be expressed as:

exp(iK.R) = 1

where: K = hb1* + kb2

* + lb3*; R = n1b1 + n2b2 +n3b3

R.K = 2(n1h+n2k+n3l) = 2……• In a reciprocal lattice, a set of reciprocal basis vectors b*

1, b*2 , b*

3 can be defined in terms of the three translational basis vectors b1, b2 , b3 in the direct space:

b*1 = 2(b2xb3)/|b1.b2xb3| Vd = |b1.b2xb3|

b*2 = 2(b2xb3)/|b1.b2xb3|

b*3 = 2(b2xb3)/|b1.b2xb3| Vr

* = |b1

*.b2*xb3

*| = 83/Vd