III nitride semiconductor substrate, epitaxial substrate, and semiconductor device

摘要

In a semiconductor device 100, it is possible to prevent C from piling up at a boundary face between an epitaxial layer 22 and a group III nitride semiconductor substrate 10 by the presence of 30×1010 pieces/cm2 to 2000×1010 pieces/cm2 of sulfide in terms of S and 2 at % to 20 at % of oxide in terms of O in a surface layer 12 with a front surface 10a having a specific plane orientation. Accordingly, a high-resistivity layer is prevented from being formed at the boundary face between the epitaxial layer 22 and the group III nitride semiconductor substrate 10. Consequently, it is possible to improve the emission intensity of the semiconductor device 100.

主权项

1. A group III nitride semiconductor substrate used in a semiconductor device, comprising a surface layer on a front surface of the group III nitride semiconductor substrate, wherein
the surface layer has a surface concentration density of 30×1010 pieces/cm2 to 2000×1010 pieces/cm2 of sulfur and 2 at % to 20 at % of oxygen, and an inclination angle of a normal axis of the front surface with respect to a c-axis is 10° to 81°.