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:
May. 05, 1998
Filed:
Mar. 11, 1997
Rashid Bashir, Santa Clara, CA (US);
Abul E Kabir, Sunnyvale, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A method of making a surface micro-machined accelerometer using a silicon-on-insulator (SOI) wafer structure. Both the acceleration (or deceleration) sensor and associated signal conditioning circuitry are monolithically fabricated on the same substrate. The top silicon layer of the SOI wafer is used as the sensing member, corresponding to the movable, common electrode of a differential capacitor pair. The components of the signal conditioning circuitry are fabricated in the SOI layer using standard SOI processing techniques. Because the top silicon layer is single crystal silicon, it does not suffer from the stress related warping common with polysilicon members. In addition, because the method described is compatible with bipolar, BiCMOS, or CMOS process flows, it may be used to fabricate faster and lower noise level signal conditioning circuitry than can be obtained using current techniques for making monolithic accelerometers.