DescriptionZinc Oxide (ZnO) can be grown as a single crystal semiconductor with very interesting properties. The bandgap is in the 3.4 eV range which makes it attractive for many of the blue and violet applications in opto-electronics as well as UV devices. It is available in bulks, in wafers of up to 2 inches, which gives it a major advantage over Gallium Nitride and other group III Nitrides.SpecificationPolishing Specifications for Substrate GradeⅠOrientation Tolerence<30ˊThickness/Diameter Tolerance±0.10 mmSurface Flatness<(λ-2λ)@632nmSurface Quality(1.0-2.0)nmParallel10ˊPerpendicular60ˊChammfer<0.2×45°Polishing Specification for Substrate Grade ⅡOrientation Tolerence<18ˊThickness/Diameter Tolerance±0.05 mmSurface Flatness<(λ/2-λ/4)@632nmSurface Quality(0.3-1.0)nmParallel1ˊPerpendicular30ˊChammfer<0.2×45°Polishing Specification for Substrate Grade ⅢOrientation Tolerence<12ˊThickness/Diameter Tolerance±0.02 mmSurface Flatness(λ/4-λ/6)@632nmSurface Quality<0.3nmParallel45〞Perpendicular20ˊChammfer<0.2×45°
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