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:
Jul. 18, 2000
Filed:
Sep. 08, 1998
Abhijeet Sathe, Fremont, CA (US);
Henry V Allen, Fremont, CA (US);
SMI Corporation, Fremont, CA (US);
Abstract
A unique backside mask for the backside of a silicon wafer which is to be diced in a rectangular shape to form a silicon pressure sensor. The backside mask is shaped to extend farther towards the center from portions adjacent to corners of the rectangular shape. In one embodiment, the mask has a cross-shape. The silicon is etched to form a diaphragm, with the corners etching more due to the silicon crystalline structure. This leaves corner regions which are less sloped compared to the sides of the cavity, being substantially vertical or even recessed. A glass substrate with a hole in it is then bonded to the backside to form the sensor.