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. 20, 1988
Filed:
Dec. 15, 1986
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A method of manufacturing a semiconductor device having a submicron pattern. A p-type semiconductor layer is formed on an n-type semiconductor substrate. Insulating films are formed on the p-type semiconductor layer. A first mask layer, such as an aluminum layer having an etching rate different from that of the insulating films, is formed on the insulating films. A second mask layer having an etching rate different from that of the first mask layer, is formed on the first mask layer. The second mask layer is patterned. A coating film having an etching rate different from that of the first insulating film, is formed on the resultant structure. The coating film is etched to be left on a side wall of the patterned second mask layer. The first mask layer is patterned, using the residual coating film and the patterned second mask layer as masks, and a pattern finer than that of the resist is formed in the first mask layer. The insulating film is patterned, using the patterned first mask layer, and a pattern finer than that of the resist is formed in the insulating film. In the p-type semiconductor layer n+-type emitter and p+ base leading regions are formed, and the n-type semiconductor layer serves as a collector.