InP Wafer Technology

product
  • 2 and 3 inch S-doped/ n-type semiconductor InP single crystal
  • VGF growth system
    • high temperature and high pressure single crystal growth furnace
    • single crystal growth control system
  • Advantage of InP based device
    • excited wavelength match to the fiber communication (1310 ~ 1550 nm)
    • high electron mobility
    • high thermal conductivity
    • low power loss
    • low noise

Applicaiton and development of InP based device

  • Optical fiber communication
    • global cable laying = earth/moon distance x 8; 15 % increase/year (ref. Corning)
    • urban development of FTTx; by Verizon/AT&T; @ Level 3
    • long haul DWDM by fiber communication increasing: 10 Gbs →40 Gbs→160 Gbs
  • Optoelectronic integration circuit
    • For a faster transmission and enhanced system function, Optical-to-Optical (OEO) conversion costs of the data transmission can not be ignored as the increased of discrete components.
    • cost considerations force the fiber communications components shift from a discrete component to a photonic integrated circuits (PIC)
    • InP photonic integrated circuits, in recent years, getting breakthrough in the optical communications as the electronic integrated circuit technology development of Si.
  • Millimeter wave in military communication
    • Technology for frequency agile digitally synthesized transmitters program (DARPA, 2003), demanding the development of transistors with cut-off frequencies of up 500 GHz。
    • Sub-millimeter wave imaging focal plane technology (DARPA, 2006), building an imaging system operating at 340 GHz。
    • Terahertz electronics program (DARPA, 2009); Phase I: 670 GHz, Phase II: 850 GHz, Phase III: 1030 GHz。

InP based optoelectronic device industry

Table. Turnover of InP device industry in USA, 2009’ (U$)

Company Epitaxy Device Total Sales Revenue (U$ M) InP Chip Sales Revenue Related Among Total (U$ M)
JDS Uniphase Yes Yes 1,200 480
Finisar Yes Yes 550 250
Infinera Yes Yes 308 280
CyOptics Yes Yes 280 250
Oclaro Yes Yes 286 115
Avago Yes Yes 1,570 390
Opnex Yes Yes 326 130
      total U$ 4,520 M total U$ 1,895 M

Ps.
  1. Turnover from the number of public information
  2. Optical communication company chosen in USA

InP based optoelectronic device industry

  • More than 150 InP based optoelectronic components manufacturers and research institutes
  • InP based optoelectronic device market status
    • sales of InP based laser and photodetectors > US$2.0 B
    • market size of InP based optoelectronic device > US$5.0 B
  • Similar to the GaAs, InP based optoelectronic device has grown and being mature for decades study.
  • Production cost
    • most important factor: lack of cheap/good InP wafer

InP wafer industry status

Only 5 global manufacturers of InP wafers

USA AXT Inc., Crystacomm Inc.
Japan Nikko Materials, Sumitomo Electric
France InPact

Nearly 80 % of the wafer supplied by Japan, and the price is expensive.

Total market opportunity

InP crystal growth process

Innovation of single crystal growth technology

Temperature gradient in VGF

Single crystal grown by various technologies

Features/ Technology VGF LEC VCZ
Material purity control excellent acceptable good
Stoichiometric control excellent hard good
Dislocation density 10 3 / cm 2 10 5 / cm 2 10 3 / cm 2
Thermal stress low high medium
Dopant control good hard acceptable
Uniformity & consistency excellent hard acceptable
Crystal diameter control easy hard hard
Labor cost low medium high
Equipment costs low medium high
Yield medium high high
Crystal length medium long medium
Automation good poor poor

Simultaneous Synthesis and VGF growth

product
  • Cornerstone
    • key technology: VGF
    • Advantage of VGF: crystal quality & yield
  • Objective
    • more streamlined steps
    • cost down: time, equipment, space, labor…
    • competitiveness: lower price product
  • Difficulty
    • hardware: heating element, crucible supporting design, high pressure gas flow control, temperature gradient…
    • urgency: funds…
  • Superiority: an expert in VGF

Comparison of InP single crystals fabricated by DTI and others

Characteristics / Manufactures DingTen (Taiwan) AXT(US) Sumitomo (Japan) InPact (France)
Growth method SS-VGF VGF VCZ LEC
Dopant sulfur sulfur sulfur sulfur
Carrier concentration ( x 1018 cm-3) ~ 1.7 0.8 ~ 8 2 ~ 8 3 ~ 10
Mobility (cm2V-1s-1) 1,400 1,000 ~ 2,500 1,000 ~ 2,000 1,300 ~1,600
Etching pit density (cm-2) < 4,000 100 ~ 5,000 500 ~ 5,000 100,000
Crystal diameter (inch) 2 2 & 3 2, 3 & 4 2 & 3

Main task in this project

  • High temperature/high pressure furnace development
  • Multiple heating system
  • Crucible and supporting desing
  • Thermal simulation and temperature gradient
  • Crystal quality analysis
  • Optoelectronic characteristics analysis
  • Crystal quality control
  • Process optimization of 2” S-doped InP single crystal
  • Process optimization of 3” S-doped InP single crystal

(I) InP single crystal

Table . Technical specifications evolution of InP single crystal through this project

Specifications Before (2009’) After (2012’ Q1)
Single crystal diameter (inch) 2 2、3
Crystal type S-doped, n-type semiconductor S-doped, n-type semiconductor
Orientation (100)±0.5° (100)±0.5°
Carrier concentration (cm-3) 1.7 x 1018 2 ~ 8 x 1018
Resistivity (ohm-cm) 1.9 x10-3 0.6 ~ 2.5 x 10-3
Electron mobility (cm2V-1SS-1) 1,900 1,000 ~ 2,000
Etching pit density (cm-2) ~ 4,000 ≤500
Yield (%) 20 50
Ingot length (inch) 1 2
Crystal growth rate (mm/h) 2 ~ 3 5

(II) high temperature/high pressure furnace

Table . Technical specifications evolution of high temperature/ high pressure furnace through this project

Specifications Before (2009’) After (2012’ Q1)
Pressure tank - materials SA106B stainless steel SA106B stainless steel
diameter (mm) 200 300
thickness of plate (mm) 15 20
max. pressure (atm) 75 100
Heating element 1 or 4 6
heater diameter (mm) 70 90
refractory Al2O3 Z-type fiber Al2O3
max. temperature (°C) 1,500 1,600
Max. working temperature (°C) 1,300 1,400
  • Advantage of SS-VGF ® DTI
    • reduce the InP single crystal growth process; diminish the facilities, space, and operator; cost down
    • get high quality and low-cost products
  • Hardware R & D
    • high temperature/high pressure tank
  • R & D capability – teamwork of materials science and engineering, electrical and electronics, mechanical engineering
    • high temperature/high pressure furnace – General manager Rudy
    • InP single crystal growth – Dr. Hu
    • analysis and QC – Mr. Jason, Dr. Chen
    • factory – Mr. Tsai

Cost Estimation

Material & Supply Unit Unit Price (US $) Unite Quantity Per Run or Ingot Total Quantity Amount (US $)
Indium* Kg $700 0.95 .95 $665
Red Phosphorous* Kg $800 0.25 .25 $220
Quartz Tube pc $200 1 1 $200
pBN Crucible pc $1500 1/10 1/10 $150
Furnace Heating pc $4000 1/50 1/50 $80
Miscellaneous for Crystal Growth run $200 1 1 $200
Simultaneous Synthesis and VGF growth, InP single crystal cost (U$/kg) $1515

Material & Supply Unit Unit Price (US $) Unite Quantity Per Run or Ingot Total Quantity Amount (US $)
Indium Phosphide Poly-Crystal* Kg $2000 1.2 1.2 $2400
Red Phosphorous* Kg $800 0.2 0.2 $176
Quartz Tube pc $200 1 1 $200
pBN Crucible pc $1500 1/10 1/10 $150
Furnace Heating pc $4000 1/50 1/50 $80
Miscellaneous for Crystal Growth Run $100 1 1 $100
Traditional processes of poly crystal synthesis and VGF growth,
InP single crystal cost (U$/kg)
$3106

*A 20% of quantity of increased due to material waste during process

  • Increase market value and share
    • Production capacity of 2” and 3” S-doped InP single crystal > 1,000 kg/year
    • Create the market value of InP wafer around U$ 8M ~ 10M (10 % of global market share), and a market value of the related laser/fiber communication device up to U$ 200M
  • Intellectual property rights/ Patent
    • 1 patent and 1 research paper every year
    • IP: furnace, heating element, supporting of crucible, high pressure gas flow controlling, key technologies of single crystal growth