| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to etch a nitride semiconductor in an aqueous solution with good reproducibility and with good controllability by a method wherein a crystal defect is increased artificially in the nitride semiconductor and the nitride semiconductor is etched by a wet etching operation. SOLUTION: A sapphire C face 11 is used as a sapphire substrate. By an electron-beam vapor deposition operation and a lift-off operation, a stripe-shaped Al2 O3 film 12 formed in advance on the sapphire substrate which is used for a growth operation. Since the quality of a crystal in the Al2 O3 film 13 which is vapor-deposited on the sapphire substrate is inferior to that of sapphire in the substrate 11, only a linear defect which is extended to the direction of a C-axis exists in a part 14 on a GaN film as a part which is grown directly on the sapphire substrate. However, in addition to the defect in the direction of the C-axis, a defect other than it is generated in a part 15 on the GaN film on the Al2 O3 vapor-deposited film. When the sapphire substrate is etched by a KOH aqueous solution, the part 14 which is grown directly on the sapphire substrate is not etched at all, and the part 15 which is grown on the Al2 O3 vapor-deposited film is hardly etched. |
