ScAlMgO₄ Crystal Substrate

ScAlMgO₄(MgScAlO₄,SCAM) crystals are hexagonal system, has a lattice constant a=0.3246nm, and c=2.5195nm. It has a rhombohedral layered structure similar to that of wurtzite nitride and zinc oxide. It is a new type of substrate material with the smallest lattice mismatch with GaN and ZnO. Its lattice mismatch ratio with GaN is about 1.8%, and the thermal expansion coefficient mismatch with GaN and ZnO epitaxial films is better than sapphire and silicon.

Parameter

Physical and chemicalcharacteristics

Properties	ScMgAlO₄
Crystal structure	hexagonal crystal system
Lattice constant	a=0.3246nm，c=2.5195nm
Density	3.64g/cm³
Mohs hardness	4-5Mohs
Thermal expansion coefficient	A=7.45×10^-6/°C

Main Specification

Materials	ScMgAlO₄
Orientation	[0001] or [10-10] <±0.5°
Parallel	10〞
Perpendicular	5ˊ
surface Quality	10/5
Wavefront Distortion	λ/4@632nm
Surface Flatness	λ/8@632nm
Clear Aperture	>95%
Chamfer	<0.1×45°
Thickness/Diameter Tolerance	±0.05 mm
Maximum dimensions	dia 50×100mm
Coatings	AR/AR@940+1030; HR@1030+HT@940+AR1030