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:
Aug. 08, 2006
Filed:
Apr. 09, 2004
Applicant:
Abdalla Aly Naem, Overijse, BE;
Inventor:
Abdalla Aly Naem, Overijse, BE;
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 29/72 (2006.01);
U.S. Cl.
CPC ...
Abstract
The intrinsic base region of a bipolar transistor is formed to avoid a chemical interaction between the chemicals used in a chemical mechanical polishing step and the materials used to form the base region. The method includes the step of forming a trench in a layer of epitaxial material. After this, a base material that includes silicon and germanium is blanket deposited, followed by the blanket deposition of a layer of protective material. The layer of protective material protects the base material from the chemical mechanical polishing step.