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:
Mar. 01, 2005
Filed:
Jan. 14, 2002
Satoshi Yamamoto, Sakura, JP;
Osamu Nakao, Sakura, JP;
Hitoshi Nishimura, Sakura, JP;
Masahiro Sato, Sakura, JP;
Satoshi Yamamoto, Sakura, JP;
Osamu Nakao, Sakura, JP;
Hitoshi Nishimura, Sakura, JP;
Masahiro Sato, Sakura, JP;
Fujikura Ltd., Tokyo, JP;
Abstract
It is an object of the present invention to provide a touch mode capacitive pressure sensor having higher pressure durability than conventional sensors. In this invention, a touch mode capacitive pressure sensor has a diaphragm made from boron-doped silicon, and the boron concentration at the top face of the diaphragm is equal to or greater than 1×10cmand less than 9×10cm. Further, in this invention, a touch mode capacitive pressure sensor has a conductive diaphragm made by doping of an impurity and anisotropic etching, and the etch pit density on the top face of the diaphragm is equal to or less than five per μm, and preferably equal to or less than one per μm. As a result, the pressure durability of the diaphragm is greatly improved.