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:
Jan. 04, 2005
Filed:
Oct. 30, 2002
Nobuo Ozawa, Tokyo, JP;
Nobuo Ozawa, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
This invention provides a method for manufacturing an electric capacitance type acceleration sensor capable of achieving high productivity in which a semiconductor manufacturing process is used. More specifically, this invention provides a method for manufacturing an electric capacitance type acceleration sensor comprising the steps of: forming a p-type low resistance layerfor diffusing thermally a boron ion by implanting the boron ion into the surface of an n-type single crystal silicon; etching the p-type low resistance layerto leave a beam partand a partto be a movable electrode; forming a silicon oxide layerto be a sacrificial film, a fixed electrode layerand a silicon nitride film layeron the surface of the silicon substrate; etching anisotrophically from the rear surface of the silicon substrate by KOH solution making the p-type low resistance layer stop etching; and forming a hollow layerby removing the silicon oxide filmby using a hydrofluoric acid solution from the rear surface of the silicon substrate.