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:
Apr. 19, 2005
Filed:
Sep. 05, 2003
Applicants:
Cheng-wen Fan, Hsin-Chu Hsien, TW;
Hua-chou Tseng, Hsin-Chu, TW;
Inventors:
Cheng-Wen Fan, Hsin-Chu Hsien, TW;
Hua-Chou Tseng, Hsin-Chu, TW;
Assignee:
United Microelectronics Corp., Hsin-chu, TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L021/331 ;
U.S. Cl.
CPC ...
Abstract
A fabrication method for heterojunction bipolar transistor is disclosed. The method uses ISSG oxide instead of conventional PECVD oxide so that the base/emitter interface damage can be reduced. Moreover, the invention replaces the conventional emitter-window/space mask with an emitter-window reverse-tone mask/line mask to minimize the critical dimension of emitter window. Furthermore, the invention also utilizes a two-steps extrinsic base implantation to form two extrinsic bases with different dopant concentrations so that the base resistance can be reduced.