Patent ID: 11908688
Assignee: SUMITOMO CHEMICAL COMPANY LIMITED
Field: Semiconductors (Electrical engineering)
Classification: CPC H  C | IPC H

Claim 6:
7. A nitride semiconductor substrate, having a diameter of 2 inches or more and having a main surface whose closest low index crystal plane is a (0001) plane,
wherein observation of the main surface of the nitride semiconductor substrate with a multiphoton excitation microscope to obtain a dislocation density from a dark spot density, reveals that:
the main surface includes a low dislocation density region with a dislocation density of less than 1×106 cm−2, and a high dislocation density region where a dislocation density is higher than the dislocation density of the low dislocation density region and is 3×106 cm−2 or less, which are arranged alternately, and
at least a part of the low dislocation density region includes a dislocation-free region of 50 μm square or more.