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. 01, 2019
Filed:
Mar. 31, 2016
Avago Technologies General Ip (Singapore) Pte. Ltd., Singapore, SG;
Kevin J. Grannen, Thornton, CO (US);
Chris Feng, Fort Collins, CO (US);
John Choy, Westminster, CO (US);
Avago Technologies International Sales Pte. Limited, Singapore, SG;
Abstract
A method is provided for forming a piezoelectric layer during a corresponding deposition sequence. The method includes sputtering aluminum nitride onto a sputtering substrate inside a reaction chamber having a gas atmosphere, the gas atmosphere initially including nitrogen gas and an inert gas, causing growth of the piezoelectric layer with a polarity in a negative direction. The method further includes adding a predetermined amount of oxygen containing gas to the gas atmosphere over a predetermined period of time, while continuing the sputtering of the aluminum nitride onto the sputtering substrate during a remainder of the deposition sequence, such that the piezoelectric layer is monolithic. The predetermined amount of oxygen containing gas causes the polarity of the aluminum nitride piezoelectric layer to invert from the negative direction to a positive direction, opposite the negative direction.