Patent ID: 8772787
Filing Date: 2014-07-08
Classification: C30B,H01L

Abstract:
1. A GaN substrate stored within an atmosphere in which the oxygen concentration is not greater than 15 vol. % and the water-vapor concentration is not greater than 20 g/m 3 , the GaN substrate having opposite sides encompassed by a peripheral edge, one of said opposite sides being a planar first principal face and the other of said opposite sides being a second principal face, said first principal face having an average roughness Ra of not greater than 20 nm and being of plane orientation having, in an arbitrary point along the first principal face and separated at least 3 mm from said peripheral edge, an off-inclination angle of between −10° and 10°, inclusive, with respect to an arbitrarily designated crystalline plane, through said arbitrary point, of plane orientation inclined between 50° and 90°, inclusive, with respect to either the (0001) plane or the (000 1 ) plane, and said second principal face having an average roughness Ra of not greater than 20 μm.