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. 05, 2000
Filed:
May. 26, 1999
Applicant:
Inventor:
Naoto Saitoh, Chiba, JP;
Assignee:
Seiko Instruments Inc., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438309 ; 438335 ; 438341 ;
Abstract
When a bipolar transistor having a buried layer is formed, the withstanding pressure of the bipolar transistor is deteriorated by upward diffusion to a great extent from the buried layer. When a buried layer is formed in a semiconductor substrate, by providing a region without impurity introduction, upward diffusion from the buried layer is controlled to prevent deterioration in the withstanding pressure.