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:
Mar. 11, 2008
Filed:
Dec. 05, 2005
Thomas A. Wallner, Pleasant Valley, NY (US);
Thomas N. Adam, Poughkeepsie, NY (US);
Stephen W. Bedell, Wappingers Falls, NY (US);
Joel P. DE Souza, Putnam Valley, NY (US);
Thomas A. Wallner, Pleasant Valley, NY (US);
Thomas N. Adam, Poughkeepsie, NY (US);
Stephen W. Bedell, Wappingers Falls, NY (US);
Joel P. De Souza, Putnam Valley, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present invention relates to bipolar junction transistors (BJTS). The collector region of each BJT is located in a semiconductor substrate surface and adjacent to a first shallow trench isolation (STI) region. A second STI region is provided, which extends between the first STI region and the collection region and undercuts a portion of the active base region with an undercut angle of not more than about 90°. For example, the second STI region may a substantially triangular cross-section with an undercut angle of less than about 90°, or a substantially rectangular cross-section with an undercut angle of about 90°. Such a second STI region can be fabricated using a porous surface section formed in an upper surface of the collector region.