Single crystal (Ge)Germanium Wafer Ge wafer:
Germanium (Ge) is the preferred lens and window material for high performance infrared imaging systems in the 8-12 um wavelength band. Its high refractive index makes Ge ideal for low power imaging systems because of minimum surface curvature. Chromatic aberration is small, often eliminating the need for correction.
Germanium is most widely used for lenses and windows in IR systems operating in the 2 um - 12 um range. Its transmission is very temperature sensitive, becoming opaque near 100°C. Environment does not cause problems because Germanium is inert, mechanically rugged, and fairly hard.
Germanium is a high index material that is used to manufacture Attenuated Total reflection (ATR) prisms for spectroscopy. Its refractive index is such that germanium makes an effective natural 50% beamsplitter without the need for coatings. It is also used extensively as a substrate for production of optical filters. Germanium covers the whole of the 8-14 micron thermal band and is used in lens systems for thermal imaging. It can be AR coated with diamond producing an extremely tough front optic.
Application as window, lens, beamsplitter, ATR prism or filter in spectrometers and in thermal imaging.
Specifications:
Ge wafer: Material: | Ge |
| Dimension Tolerance | +0.0, -0.1mm |
| Thickness Tolerance: | ± 0.1mm |
| Surface quality: | 60/40 |
| Clear Aperture: | >85% |
| Flatness: | λper 25mm |
| Parallelism: | 3' |
| Bevel: | <0.25mm X 45° |
| Coating: | Upon requirement |
General Properties of Germanium Wafer | General Properties Structure | Cubic, a = 5.6754 Å |
| Density: 5.765 g/cm3 |
| Melting Point: 937.4 oC |
| Thermal Conductivity: 640 |
| Crystal Growth Technology | Czochralski |
| Doping available | Undoped | Sb Doping | Doping In or Ga |
| Conductive Type | / | N | P |
| Resistivity, ohm.cm | >35 | < 0.05 | 0.05 - 0.1 |
| EPD | < 5x103/cm2 | < 5x103/cm2 | < 5x103/cm2 |
| < 5x102/cm2 | < 5x102/cm2 | < 5x102/cm2 |
Grades and Application of Germanium wafer | Electronic Grade | Used for diodes and transistors, |
| Infrared or opitical Grade | Used for IR optical window or disks,opitical components |
| Cell Grade | Used for substrates of solar cell |
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| Standard Specs of Germanium Crystal and wafer |
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| Crystal Orientation | <111>,<100> and <110> ± 0.5o or custom orientation |
| Crystal boule as grown | 1" ~ 6" diameter x 200 mm Length |
| Standard blank as cut | 1"x 0.5mm | 2"x0.6mm | 4"x0.7mm | 5"&6"x0.8mm |
| Standard Polished wafer(One/two sides polished) | 1"x 0.30 mm | 2"x0.5mm | 4"x0.5mm | 5"&6"x0.6mm |
| Special size and orientation are available upon requested Wafers |
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| 4 inch Ge wafer Specification | | | | |
| Doping | P | | | |
| Doping substances | Ge-Ga | | | |
| Diameter | 100±0.25 mm | | | |
| Orientation | (100) 9° off toward <111>+/-0.5 | | |
| Off-orientation tilt angle | N/A | | | |
| Primary Flat Orientation | N/A | | | |
| Primary Flat Length | 32±1 | mm | | |
| Secondary Flat Orientation | N/A | | | |
| Secondary Flat Length | N/A | mm | | |
| cc | (0.26-2.24)E18 | /c.c | | |
| Resistivity | (0.74-2.81)E-2 | ohm.cm | | |
| Electron Mobility | 382-865 | cm2/v.s. | | |
| EPD | <300 | /cm2 | | |
| Laser Mark | N/A | | | |
| Thickness | 175±10 | μm | | |
| TTV | <15 | μm | | |
| TIR | N/A | μm | | |
| BOW | <10 | μm | | |
| Warp | <10 | μm | | |
| Front face | Polished | | | |
| Back face | Ground | | | |
Germanium Wafer Process
In the germanium wafer production process, germanium dioxide from the residue processing is further purified in chlorination and hydrolysis steps.
1)High purity germanium is obtained during zone refining.
2)A germanium crystal is produced via the Czochralski process.
3)The germanium wafer is manufactured via several cutting, grinding, and etching steps.
4)The wafers are cleaned and inspection. During this process, the wafers are single side polished or double side polished according to custom requirement, epi-ready wafercomes.
5)The wafers are packed in single wafer containers, under a nitrogen atmosphere.
Application:
Germanium blank or window are used in night vision and thermographic imaging solutions for commercial security, fire fighting and industrial monitoring equipment. Also, they are used as filters for analytical and measuring equipment, windows for remote temperature measurement, and mirrors for lasers.
Thin Germanium substrates are used in III-V triple-junction solar cells and for power Concentrated PV (CPV) systems.
Qinhuangdao Intrinsic Crsytal Technology Co., Ltd, based in China, is a recognized leader in high-performance optical solutions across a broad infrared spectrum. Combining adequate IR material supply, extensive fabricating experience, and the standardized service, U-Optical specializes in producing high-precision IR optical components for the Medical/Life Sciences, Defense & security, Semiconductor, and Industrial OEM markets. From optics designing, to material purchase, to volume production, our company endeavor to optimize your IR products for performance, cost, quality and delivery.
Our Strengths
Ample, stable and cost-efficient supply of IR materials.
ICC also offers the ability to combine infrared material supply, precision optical processes, various coating, reliable inspection and commercial service into a complete procedure, providing full professional support for both optics and trades. This enables our customers to obtain the highest level of optical integration and business advantage, minimizing time and cost while ensuring quality, performance and manufacturability.
Consistent and high-performance manufacturing
During its years of operational experience, ICC have developed unique techniques of micro-polishing which enable to easily produce elements needed for high transmission and low scattering and absorption applications.
The accumulated experience in the IR optics market, in addition to the high qualifications and strong optical background of the company's leading staff allow U-Optics to be a reliable supplier to many OEM customers and R&D institutions around the world.
Excellent quality and efficient service
From design to delivery, our material control, in-process testing and final inspections assure that our products meet your highest specifications and quality standards.
Our sales team possess a wide range of experience of not only optics, but also the international business services. By staying close to our customers and giving straightforward honest advice, we are confident to provide our overseas customers with the excellent IR products from China.
Competitive Prices
ICC can offer the customers with most competitive prices and high quality of products, supported by the close associations with the domestic suppliers, its comprehensive optical manufacturing capabilities, as well as its strong ability in exploring overseas markets.
Stable and reliable business partner
We place equal focus on processing technique, customer service and innovative research. Meanwhile, we create customer value by understanding customer needs, by unconditionally guaranteeing our work and by keeping abreast of customer developments.
Contact us today to discuss your needs. To my email: Optics@intrnsiccrysal. COM Tel: 18833844340
