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:
Feb. 04, 1992
Filed:
Jun. 05, 1990
Applicant:
Inventor:
Kenji Hirakawa, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; H01L / ;
U.S. Cl.
CPC ...
437 32 ; 437151 ; 437152 ; 437162 ; 148D / ; 357 35 ;
Abstract
In a self-alignment type-lateral bipolar transistor and a manufacturing method thereof, the base width is determined not by the image resolution limit of the lithography technique, as in the prior art, but by the impurity diffusion from the polysilicon layer 118. Therefore, the self-alignment type lateral-structure pnp bipolar transistor and the manufacturing method permit the base width to be as small as possible, resulting in improvement of frequency characteristics, and reducing the size of the transistor element.