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. 24, 1976
Filed:
May. 10, 1974
Mikio Takagi, Tokyo, JA;
Hajime Kamioka, Tokyo, JA;
Kazufumi Nakayama, Kawasaki, JA;
Haruo Shimoda, Tama, JA;
Fujitsu Limited, Kawasaki, JA;
Abstract
A method of making a semiconductor device capable of high-speed operation is disclosed in which when the current gain-bandwidth is increased by the formation of a shallow base region. A side etching process is used to decrease the base spreading resistance and to allow ease in the formation of an emitter region of fine pattern. When the emitter region is formed by using polycrystalline silicon as a source of impurity diffusion, that area of an insulating film on a semiconductor substrate which adjoins the polycrystalline silicon is removed before the impurity diffusion so as to prevent an abnormal diffusion phenomenon.