| abstract |
An internal quantum efficiency of a device formed on a group III nitride semiconductor substrate is improved. A substrate preparation step S10 for preparing a sapphire substrate, a heat treatment step S20 for performing a heat treatment on the sapphire substrate, a pre-flow step S30 for supplying a metal-containing gas onto the sapphire substrate, and a growth on the sapphire substrate. Temperature: 800 ° C. or more and 950 ° C. or less, pressure: buffer layer forming step S40 for forming a buffer layer under growth conditions of 30 to 200 torr, and growth temperature: 800 ° C. or more and 1025 ° C. or less, pressure: And a growth step S50 for forming a group III nitride semiconductor layer under a growth condition of 30 to 200 torr and a growth rate of 10 μm / h or more. [Selection] Figure 3 |