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:
Jun. 12, 2001
Filed:
May. 03, 1999
Masato Sugimoto, Osaka, JP;
Katsu Takeda, Osaka, JP;
Yoshihiro Tomita, Osaka, JP;
Osamu Kawasaki, Tsuzuki-gun, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A wafer with a reversed domain is prepared for two piezoelectric single crystal plates and of about the same thickness by using direct bonding without any adhesive. Driving electrodes are formed on two principal planes of the wafer with a reversed domain to provide a piezoelectric resonator. A piezoelectric resonator having the structure with a reversed polarization and using odd-order vibration modes vibrating with a fundamental wave has a wavelength of a thickness thereof and suppresses scattering of the thickness of the domains with a reversed polarization. In the direct bonding, the axes of the spontaneous polarization of the two piezoelectric single crystal plates are reverse to each other and crystalline axes other than the axes of polarization are shifted intentionally by an angle other than zero. Thus, spurious modes are suppressed in a simple way.