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. 04, 2019
Filed:
Jul. 22, 2015
Cindy X. Qiu, Brossard, CA;
Ishiang Shih, Brossard, CA;
Chunong Qiu, Brossard, CA;
Andy Shih, Brossard, CA;
Julia Qiu, Brossard, CA;
Yi-chi Shih, Los Angeles, CA (US);
Cindy X. Qiu, Brossard, CA;
Ishiang Shih, Brossard, CA;
Chunong Qiu, Brossard, CA;
Andy Shih, Brossard, CA;
Julia Qiu, Brossard, CA;
Yi-Chi Shih, Los Angeles, CA (US);
Other;
Abstract
In wireless communications, many radio frequency bands are used. For each frequency band, there are two frequencies, one for transmitting and the other for receiving. As the band widths are small and separation between adjacent bands is also small, many band pass filters with different band pass frequencies are required for each communication unit such as mobile handset. The invention provides tunable film bulk acoustic resonators TFBARs containing semiconducting piezoelectric layers and methods for tuning and adjusting the resonant properties. When a DC biasing voltage is varied, both the depletion region thickness and neutral region thickness associated in the semiconducting piezoelectric layers varies leading to changes in equivalent capacitances, inductance and resistances and hence the resonance properties and frequencies. A plurality of the present TFBARs are connected into a tunable oscillator or a tunable and selectable microwave filter for selecting and adjusting of the bandpass frequency by varying the biasing voltages.