Patent · US Active

Method of improving surface flatness of group-III nitride crystal, substrate for epitaxial growth, and semiconductor device

US7687824B2 · kind B2 · utility

4Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 24, 2005
Grant dateMar 30, 2010
Priority date
Expiry dateNov 17, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/3245
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A heating process is performed in a nitrogen atmosphere at a temperature of not less than 1650° C. upon an epitaxial substrate including a single crystal base and an upper layer made of a group-III nitride crystal and epitaxially formed on a main surface of the single crystal base. The result shows that the heating process reduces the number of pits in a top surface to produce the effect of improving the surface flatness of the group-III nitride crystal. The result also shows that the dislocation density in the group-III nitride crystal is reduced to not more than one-half the dislocation density obtained before the heat treatment.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.