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:
Jan. 21, 2003
Filed:
May. 09, 2001
Applicant:
Inventor:
David Neil Casey, Lancashire, GB;
Assignee:
Zetex PLC, , GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 2/970 ;
U.S. Cl.
CPC ...
H01L 2/970 ;
Abstract
A guard ring structure formed around the periphery of a bipolar semiconductor device. A guard region ( ) is formed in a substrate ( ) of the device so as to extend adjacent a peripheral portion of the device. An insulating layer ( ) is formed on the substrate between the peripheral portion of the device and the guard region ( ). A polysilicon layer ( ) is formed on the insulating layer ( ) and covered with a layer of densified dielectic ( ). Electrical interconnections are provided between the polysilicon layer ( ) and the guard region ( ) at spaced apart portions of the device where the guard structure does not need to be protected by the densified dielectric.