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:
Dec. 28, 1999
Filed:
May. 15, 1996
Takayuki Gomi, Tokyo, JP;
Sony Corporation, , JP;
Abstract
A logic circuit is formed of an I.sup.2 L cell structure in which a difference of switching speeds at every collector in a multi-collector structure is small. In a semiconductor device in which an integrated injection logic cell including a constant current source transistor and a switch transistor is formed on a common semiconductor substrate, a first semiconductor layer (13) doped with a first conductivity type impurity and a second semiconductor layer (19) doped with a second conductivity impurity are electrically isolated from each other on a semiconductor substrate. A plurality of collector electrodes of the switch transistor and a plurality of collector regions (20) based on diffusion of impurity are formed by the second semiconductor layer (19). The first semiconductor layer (13) includes a base electrode deriving portion, and a direct contact portion which directly contacts with the semiconductor substrate between a plurality of collector regions (20). An external base region (17) is formed by diffusion of first conductivity type impurity from the direct contact portion.