Patent ID: 9012936
Filing Date: 2015-04-21
Classification: H01L,Y10T

Abstract:
1. A sapphire substrate having a principal surface for growing a nitride semiconductor to form a nitride semiconductor light emitting device, the sapphire substrate comprising a plurality of projections on the principal surface, wherein each projection of the plurality of projections is separated from each adjacent projection of the plurality of projections, wherein each of the projections has a bottom that has a substantially triangular shape, wherein each side of the bottom of the projections has a depression in its center, wherein extended portions of the bottoms of the respective projections extend in a direction that is within a range of ±10 degrees of a crystal axis “a” of the sapphire substrate, and wherein the plurality of projections are arranged so that any straight line that is drawn at any position in any direction in a plane including the bottoms of the plurality of projections passes through a geometric area of the bottom of at least one of projections.