Patent ID: 9337390
Filing Date: 2016-05-10
CPC Classification: C30B,H01L

Claim Text:
1. A method for manufacturing a sapphire substrate in which a plurality of projections are formed on a C-plane of the sapphire substrate by etching, comprising: forming a patterned etching mask on the C-plane of the sapphire substrate; etching the sapphire substrate until the projections are formed, wherein each of the projections formed by the etching has a substantially triangular pyramidal-shape and has a plurality of side surfaces, a pointed top and a bottom, wherein the bottom of each of the projections has a substantially triangular shape having three outwardly curved arc-shaped sides, and each of the plurality of side surfaces has a substantially triangular shape having vertexes located at the top of the projections and at both ends of a respective side of the bottom of the projections, and wherein the projections are arranged on vertexes of a triangular lattice, and an orientation of the bottom of the projections conforms with an orientation that is rotated by about 30 degrees from an orientation of a triangle of the triangular lattice; and removing the etching mask from the sapphire substrate.