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:
Oct. 20, 1998
Filed:
Jun. 27, 1996
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A polysilicon thin film is formed on a silicon substrate by LPCVD technique. At this time, by a performing film formation at a low temperature of approximately 620.degree. C., for example, an irregularities portion is formed on the surface thereof. A silicon oxide film that serves as a sacrificial layer is formed thereon and, on this sacrificial layer, a polysilicon thin film that serves as a movable portion forming thin film is formed. Then, the silicon oxide film beneath this polysilicon thin film is removed by wet etching to thereby form a movable portion. As a result, the movable portion of a beam structure that is composed of the thin film is disposed over the silicon substrate at a prescribed distance therefrom. Although an etchant-replacing liquid enters between the movable portion and the substrate whereby the movable portion is attracted toward the substrate, the movable portion is prevented from adhering to the substrate by means of the irregularities portion.