DescriptionScAlMgO4(MgScAlO4,Website:http://www.meta-laser.com,SCAM) crystal is a kind of GaN and ZnO heteroepitaxy recently developed with the ideal substrate material, currently it match the GaN and ZnO best in the new substrate materials.ScAlMgO4 crystals are hexagonal system,which lattice constant a = 0.3246 nm, c = 2.5195 nm, with rhombohedron layered structure, similar to wurtzite nitrides and the structure of zinc oxide.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°