Patent · US Expired

SAW component having an improved temperature coefficient

US7459991B2 · kind B2 · utility

10Cited by

7References

22Claims

0Family size

Assignee

EPCOS AG · DE

Inventors

Werner Ruile · Birkenfeld, DE
Ulrike Roesler · Hebertshausen, DE
Ulrich Wolff · Munich, DE
Anton Leidl · Munich, DE
Gerd Scholl · Hersbruck, DE
Markus Hauser · Feldafing, DE
Ulrich Knauer · Munich, DE

Key dates

Filing date	Dec 16, 2003
Grant date	Dec 2, 2008
Priority date	—
Expiry date	May 25, 2025

Classification

Technology area (CPC H)Electricity
CPC primaryH03H9/14538
WIPO fieldBasic communication processes
WIPO sectorElectrical engineering

Abstract

An apparatus including a piezoelectric substrate having at least one transducer electrode structure. The structure having a metallization formed by one or more metals with a mean specific density that is at least 50% higher than that of aluminum. The structure having a compensation layer that is applied fully or partially over the metallization. The compensation layer is of a material having a temperature dependence of elastic constants that counteracts the temperature coefficient of frequency of the substrate. The compensation layer has a thickness that is less than 15% of an acoustic wavelength of a wave capable of propagation in the structure.

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