Patent · US Expired

Thin film capacitor

US7176510B2 · kind B2 · utility

3Cited by
5References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 24, 2004
Grant dateFeb 13, 2007
Priority date
Expiry dateNov 7, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01G7/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A thin film capacitor includes a pair of electrodes and a dielectric layer having piezoelectricity sandwiched therebetween. The phase characteristic of an impedance resulting from application of a voltage to the pair of electrodes peaks periodically according to a frequency of a signal to be inputted or outputted. The frequency of the signal is adjusted to fall in between the values representing the adjacent peaks. Since there are periodic peak values that depend upon the frequency of the inputted or outputted signal, in fabricating a band-pass filter, a higher attenuation can be attained by ensuring that the peak value stands at a low-frequency level. Thus, a higher attenuation can be attained at low frequencies without sacrificing the band-pass characteristic, whereby making it possible to produce a band-pass filter that is excellent in band-pass characteristic.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.