|Material||ZnO single crystal||Size(mm)||25×25×0.5, 10×10×0.5, 10×5×0.5, 5×5×0.5|
|Orientation||<0001>, <11-20>, <10-10>±0.5°||Polishing||Single or Double surface polished (SSP or DSP)|
|Transparency Range||0.4-0.6 µm; > 50%@2µm||Surface Roughness||Ra: ≦0.5nm|
Note: customize special orientation and size of the substrate is available.
|Crystal Structure||M6||Lattice Constant||a=3.252Å c=5.313 Å|
|Melt Point(℃)||1975||Coefficient of Thermal Expansion||a /6.5 x 10-6 /℃
c /3.7 x 10-6 /℃
|Specific Heat(g.m)||0.125 cal||Pyroelectricity Constant||1200 mv/k @ 300 ℃|
|Thermal Conductivity(cm/k)||0.006 cal||Chemical Stability||Insoluble in water|
ZnO has the potential to become the substrate material of choice for GaN. Like GaN, it has a wurtzite structure, with lattice constants closely matches to GaN (a=3.249, c=5.205). The lattice mismatch between ZnO and GaN isε=0.017. Perhaps most important is that it is a soft compliant material which is believed to take up the lattice stress in preference to the growing GaN layer. It suffers from the drawback that it dissociates in ammonia at temperatures above 600°C. With its wide bandgap, Zinc Oxide is proved very useful in optical applications as well as many high speed electronics. ZnO is also used as a substrate for epitaxial growth.