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:
Jul. 29, 1997
Filed:
Apr. 23, 1996
Applicant:
Inventor:
Susumu Asada, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437-8 ; 437 24 ;
Abstract
Impurity concentration profile is determined for a diffused layer of a semiconductor substrate by repeating a combination of etching of the diffused layer and measuring sheet resistance and/or hall resistance by using electrodes formed on the diffused layer. The etching of the diffused layer by a small amount is repeated in first portions aligned in the depth direction of the diffused layer, followed by etching of adjacent second portions aligned in the depth direction. The etching may be replaced by implanting inactive ions into portions of the diffused layer to generate high resistance for the portions.