Patent · US Active

Method for producing semiconductor substrate

US8076223B2 · kind B2 · utility

0Cited by
10References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 4, 2007
Grant dateDec 13, 2011
Priority date
Expiry dateJul 6, 2028

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/02661
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

The present invention is a method for producing a semiconductor substrate, including steps of forming a SiGe gradient composition layer and a SiGe constant composition layer on a Si single crystal substrate, flattening a surface of the SiGe constant composition layer, removing a natural oxide film on the flattened surface of the SiGe constant composition layer, and forming a strained Si layer on the surface of the SiGe constant composition layer from which the natural oxide film has been removed, wherein the formation of the SiGe gradient composition layer and the formation of the SiGe constant composition layer are performed at a temperature T1 that is higher than 800° C., the removal of the natural oxide film from the surface of the SiGe constant composition layer is performed in a reducing atmosphere through a heat treatment at a temperature T2 that is equal to or higher than 800° C. and lower than the temperature T1, and the formation of the strained Si layer is performed at a temperature T3 that is lower than the temperature T1. This method enables epitaxial growth of the strained Si layer on the flattened SiGe layer without degrading surface flatness of the SiGe layer.

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