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. 16, 1997
Filed:
Oct. 05, 1995
Shigeki Takahashi, Okazaki, JP;
Mitsuhiro Kataoka, Kariya, JP;
Tsuyoshi Yamamoto, Chiryu, JP;
Yuuichi Takeuchi, Chita-gun, JP;
Norihito Tokura, Okazaki, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A manufacturing method for a semiconductor device, which can attain a low ion voltage in a manufacturing method for a semiconductor device involving a process for forming a groove by etching prior to selective oxidation, selectively oxidizing a region including the groove and thereby making a channel part of the groove, is disclosed. A groove part is thermally oxidized by using a silicon nitride film as a mask. A LOCOS oxide film is formed by this thermal oxidation, and concurrently a U-groove is formed on the surface of an n.sup.- -type epitaxial layer eroded by the LOCOS oxide film, and the shape of the U-groove is fixed. A curve part formed during a chemical dry etching process remains as a curve part on the side surface of the U-groove. Then, an n.sup.+ -type source layer is formed by means of thermal diffusion to a junction thickness of 0.5 to 1 .mu.m, and a channel is set up as well. The junction depth obtained by this thermal diffusion is set up more deeply than the curve part which is formed during the above etching and remains on the side surface of the U-groove after the above selective thermal oxidation.