METHOD FOR FORMING IDENTIFICATION MARKS ON REFRACTORY MATERIAL SINGLE CRYSTAL SUBSTRATE, AND REFRACTORY MATERIAL SINGLE CRYSTAL SUBSTRATE

摘要

An identification mark formation method for forming an identification mark on a refractory material single crystal substrate that is made of one selected from the group consisting of sapphire, gallium nitride, aluminum nitride, diamond, boron nitride, zinc oxide, gallium oxide, and titanium dioxide is disclosed. The method includes: (a) scanning a principal surface of the refractory material single crystal substrate with a laser beam at a first energy density such that a groove is formed in the principal surface of the refractory material single crystal substrate, thereby forming an identification mark in the principal surface of the refractory material single crystal substrate; and (b) scanning an inside of the groove of the refractory material single crystal substrate with a laser beam at a second energy density that is lower than the first energy density.

主权项

1. A refractory material single crystal substrate which has an identification mark on a principal surface, the identification mark being constituted of one or more grooves, and the refractory material single crystal substrate being made of a single crystal which is formed by one selected from the group consisting of sapphire, gallium nitride, aluminum nitride, diamond, boron nitride, zinc oxide, gallium oxide, and titanium dioxide,
wherein a width of the groove is not less than 50 μm and less than 0.5 mm, and a depth of the groove is not less than 10 μm, and a surface roughness Ra of an internal surface of the groove is not more than 1 μm.