Tunable/Switchable Thin Film Bulk Acoustic Wave (BAW) resonator using thin electrostrictive film under oe bias for GHz applications

Conference: Smart Systems Integration 2008 - 2nd European Conference & Exhibition on Integration Issues of Miniaturized Systems - MOMS, MOEMS, ICS and Electronic Components
04/09/2008 - 04/10/2008 at Barcelona, Spain

Proceedings: Smart Systems Integration 2008

Pages: 8Language: englishTyp: PDF

Personal VDE Members are entitled to a 10% discount on this title

lvira, Brice; Reinhardt, Alexandre; Defay, Emmanuel; Aid, Marc (CEA-LETI MINATEC, Grenoble, France)
Volatier, Alexandre (TriQuint, Orlando, USA)
Ancey, Pascal (STMicroelectronics, Advanced R&D, Crolles, France)

In the last decade, the emerging world market of Bulk Acoustic Wave (BAW) resonators for RF filtering functions in front-end modules has become a strong business issue for many companies. Among the leader companies, Avago first started commercialization of filters based on air gap Film Bulk Acoustic Resonator (FBAR) in 1999 whereas Infineon reached the market with Solidly Mounted Resonators (SMR) in 2002. Up to now, these filters were designed to satisfy one RF band requirements only (either GSM, PCS or DCS, ...). Recently, a new challenge must be addressed for BAW filters. The trend of providing reconfigurable front-ends able to operate in multiple standard Radio-Frequency (RF) bands of telecommunication systems involves an upcoming development of more complex tunable/switchable BAW filters. In this condition, electrostrictive materials in BAW devices are very promising candidates to fulfill this function in replacement of the classical piezoelectric materials. In this work, we investigate electrostrictive Strontium Titanate (STO) as a new material in a SMR. This material exhibits piezoelectric-Iike behavior induced by electrostriction when excited by an RF signal superimposed over a Direct Current (DC) bias. This work first reports design, process, simulation and characterization of such an acoustic resonator.