| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a group III nitride semiconductor single crystal from which a growth substrate is easily released and which is excellent in crystallinity and a method for producing a GaN substrate.SOLUTION: A mask layer 140 is formed on a GaN substrate G as a growth substrate 10. Next, a plurality of recesses X11 extending from the mask layer 140 to the GaN substrate G10 are formed by photolithography. It together with a raw material for a single crystal is placed in a crucible, and the pressure and the temperature are elevated. The GaN substrate G10 exposed through the recesses X11 undergoes melt back with a flux. By the melting of the GaN substrate G10, the recesses X11 are broadened to form recesses X12. A GaN layer 150 grows from the surfaces 144 of the mask layer 140 as a starting point. In this time, the GaN layer 150 grows without covering the recesses X12. |
