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. 04, 1990
Filed:
Mar. 12, 1990
Shin-ichi Taka, Yokosuka, JP;
Jiro Ohshima, Kitakyushu, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
This invention discloses a method of manufacturing an SST bipolar transistor, and the manufacturing method is capable of defining the size of a base region of the SST bipolar transistor. An insulating film and a spacer film serving as a spacer are sequentially formed in a bipolar transistor forming region on the main surface of a semiconductor substrate. Thereafter, the spacer film is patterned into a spacer film pattern for defining the size of the base region. A second insulating film, a base electrode pattern and a third insulating film are sequentially formed on the spacer film pattern. A first opening which reaches the spacer film pattern through the second insulating film, the base electrode pattern and the third insulating film is formed. The spacer film pattern is etched from the first opening to form a second opening having a diameter larger than that of the first opening. The insulating film exposed in the second opening is etched. The size of the base region on the major surface of the semiconductor substrate is defined by the size of the second opening.