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. 26, 1996
Filed:
Mar. 30, 1994
Shinji Saitou, Suita, JP;
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
A compact and solid-state mechanical sensor comprises a magnetic layer having magnetostriction and a planar coil for detecting a mechanical property as a change in impedance. The sensitivity of the sensor is improved with heat treatment to relax the internal stress in the magnetic layer. The magnetic layer 12a of 5 .mu.m of thickness is formed on a titanium substrate 11 of 9.4 ppm/.degree.C. thermal expansion coefficient. The magnetic layer comprises an Fe-based amorphous alloy film prepared with a sputtering method, and it has a composition of Fe 74, Cr 4, Si 13 and B 9 (at %), +22 ppm of saturation magnetostriction constant and 8.0 ppm/.degree.C. of thermal expansion coefficient. An insulator layer 13a made of SiO.sub.x of 2 .mu.m of thickness on the magnetic layer 12a, and a planar coil 14 and input/output terminals 15a, 15b made of aluminum of 2 .mu.m of thickness is formed on the insulator layer 13a. The planar coil 14 is made of a linear conducting line having a form wherein a spiral coil is folded as a rectangular shape by 90.degree..