| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an epitaxial substrate which is advantageous in cost, and which allows the materialization of a semiconductor device for high-frequency operation having good characteristics. <P>SOLUTION: The method comprises: epitaxially forming an underlying layer made of a first group III nitride having an insulating property on a base made of SiC or Si having conductivity by means of MOCVD so as to have a substantially nonperiodic uneven structure on its surface and to have an average surface roughness between 0.5μm and 1μm inclusive; epitaxially forming a channel layer made of GaN on the underlying layer; and epitaxially forming a barrier layer made of Al<SB POS="POST">x</SB>Ga<SB POS="POST">1-x</SB>N(0<x<1) on the channel layer. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
