Ge(Germanium) Single Crystals and Wafers
Single crystal (Ge)Germanium Wafer
PAM-XIAMENoffers semiconductor materials,Ge(Germanium) Single Crystals and Wafers grown by VGF / LEC
1. Properties of Germanium Wafer
1.1 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|
|Resistivity, ohm.cm||>35||< 0.05||0.05 – 0.1|
|EPD||< 5×103/cm2||< 5×103/cm2||< 5×103/cm2|
|< 5×102/cm2||< 5×102/cm2||< 5×102/cm2|
1.2.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|
1.3.Standard Specs of Germanium Crystal and wafer
|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
2. Specification of Germanium Wafer
2.1 Specification of Germanium Wafer of 2”,3”,4”and 6”size
|Conduction Type||n-type, p type, undoped|
|Dopant||Gallium or Antimony||—|
|Wafer Diamter||2, 3,4 & 6||inch|
|OF||EJ or US||—|
|Carrier Concentration||request upon customers|
|Resistivity at RT||(0.001~80)||Ohm.cm|
|Etch Pit Density||<5000||/cm2|
|Laser Marking||upon request||—|
|Surface Finish||P/E or P/P||—|
|Package||Single wafer container or cassette||—|
2.2 Germanium Wafer for Solar Cell
|4 inch Ge wafer Specification||for Solar Cells||—|
|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|
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 wafer comes.
5)The wafers are packed in single wafer containers, under a nitrogen atmosphere.
4.Application of Germanium:
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.
5.Test of Germanium Wafer:
The resistivity of the Germanium crystal was measured by Four Probe Resistance Tester, and the surface roughness of Germanium was measured by profilometer.