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:
May. 08, 2001
Filed:
Nov. 20, 1997
Applicant:
Inventors:
Tatsuya Suzuki, Tokyo, JP;
Tohru Aoyama, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08B 2/302 ;
U.S. Cl.
CPC ...
C08B 2/302 ;
Abstract
In order to reduce boron concentration between a silicon substrate and an Si or Si,Ge,layer which is epitaxially grown in a CVD (chemical vapor deposition) apparatus, the silicon substrate is pretreated, before being loaded into the CVD apparatus, such as to prevent the substrate from being contaminated by boron in a clean room. Further, in accordance with one embodiment, a CVD growth chamber itself is cleaned, before the substrate is loaded into the growth chamber, using an F,gas at a predetermined temperature of the substrate, thereby to remove boron residues in the growth chamber.