| 摘要 |
Fracture-resistant gallium nitride substrate, and methods of testing for and manufacturing such substrates are made available. A gallium nitride substrate (10) is provided with a front side (12) polished to a mirrorlike finish, a back side (14) on the substrate side that is the opposite of the front side (12). A damaged layer (16) whose thickness d is 30 µ m or less is formed on the back side (14). Given that the strength of the front side (12) is I 1 and the strength of the back side (14) is I 2 , then the ratio I 2 / I 1 is 0.46 or more. |
