Abstract
A new type of hybrid BAW/SAW device has been recently proposed1 and experimentally verified2,3.
In this resonator, bulk acoustic waves (BAW) excited in piezoelectric pillars combine with surface
acoustic waves (SAW) in the underlying substrate. The pillars are arranged in a periodic array with 2
pillars per period connected to opposite potentials. Neighboring pillars operate as two pistons with a phase
shift of 180° and excite under certain conditions a standing or a travelling SAW on the non-piezoelectric
substrate. The pillar array must have a spatial period close to the SAW wavelength of the substrate (λ SAW).
Using a substrate with a high acoustic Q, such resonators exhibit as well high Q factors, provided that the
pillars are regularly shaped. The potentially large coupling coefficient and the absence of an acoustical
isolation like a Bragg mirror or an air gap, and the possibility to tune the operational frequency by the
pitch of interdigitated electrodes, makes the concept interesting for RF filters in telecommunication
In this resonator, bulk acoustic waves (BAW) excited in piezoelectric pillars combine with surface
acoustic waves (SAW) in the underlying substrate. The pillars are arranged in a periodic array with 2
pillars per period connected to opposite potentials. Neighboring pillars operate as two pistons with a phase
shift of 180° and excite under certain conditions a standing or a travelling SAW on the non-piezoelectric
substrate. The pillar array must have a spatial period close to the SAW wavelength of the substrate (λ SAW).
Using a substrate with a high acoustic Q, such resonators exhibit as well high Q factors, provided that the
pillars are regularly shaped. The potentially large coupling coefficient and the absence of an acoustical
isolation like a Bragg mirror or an air gap, and the possibility to tune the operational frequency by the
pitch of interdigitated electrodes, makes the concept interesting for RF filters in telecommunication
| Original language | English |
|---|---|
| Publication status | Published - 27 May 2018 |
| Event | International Symposium on Applications of Ferroelectrics - Hiroshima, Japan Duration: 27 May 2018 → 1 Jun 2018 http://hiroshima2018.com/meeting-web/ieee_isaf.html |
Conference
| Conference | International Symposium on Applications of Ferroelectrics |
|---|---|
| Abbreviated title | ISAF |
| Country/Territory | Japan |
| City | Hiroshima |
| Period | 27/05/18 → 1/06/18 |
| Internet address |
Keywords
- aluminium scandium nitride
- thin film
- resonator
- etching