The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 1995
Filed:
Nov. 14, 1994
Hiroshi Naruse, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a method of manufacturing a bonded semiconductor substrate, a SiGe mixed crystal layer, a silicon layer containing N-type impurities, a SiGe mixed crystal layer containing N-type impurities of high concentration, and a silicon layer containing N-type impurities of high concentration are formed in this order on a top surface of a silicon substrate by an epitaxial growth process to form a first semiconductor substrate. A silicon oxide film is formed on a surface of a silicon substrate to form a second semiconductor substrate. The first and second semiconductor substrates are bonded to each other by heat treatment, with their top surfaces contacting each other. The first semiconductor substrate is etched from the back surface thereof until the SiGe mixed crystal layer is exposed, and the SiGe mixed crystal layer is etched until the silicon layer containing N-type impurities is exposed. This method prevents the thickness of the element forming layer from varying.