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:
Feb. 13, 2018
Filed:
Aug. 13, 2014
Murata Manufacturing Co., Ltd., Nagaokakyo-shi, Kyoto-Fu, JP;
Kiyoto Araki, Nagaokakyo, JP;
Keiichi Umeda, Nagaokakyo, JP;
MURATA MANUFACTURING CO., LTD., Nagaokakyo-Shi, Kyoto-Fu, JP;
Abstract
A method for manufacturing a piezoelectric bulk acoustic wave element by forming a sacrificial layer on a part of a primary surface of a substrate. A piezoelectric film sandwiched between a pair of electrodes is formed on the primary surface of the substrate so as to cover the sacrificial layer, the piezoelectric film being formed from scandium-containing aluminum nitride having a scandium atomic concentration with respect to the total number of scandium atoms and aluminum atoms of more than 24 atomic percent. An etching step of removing the sacrificial layer by etching is performed. Prior to the etching step, a protective film formed from aluminum nitride or scandium-containing aluminum nitride having a lower scandium atomic concentration than that of the piezoelectric film is provided so as to cover at least a part of a portion of the piezoelectric film located in a region in which the sacrificial layer is provided.