Abstract
By applying a new shear horizontal (SH)-type leaky surface acoustic wave (LSAW) excited by interdigital transducers (IDTs) and reflectors made of Ta or W on an ST-cut 90°X-propagation (direction perpendicular to X-axis) quartz substrate, we succeeded in fabricating very small resonator filters (1/5-1/4 of conventional device sizes). However, the Ta and W films used in our filters were β-Ta and β-W, which have resistances higher than that of an Al film. α-Ta and α-W films with very low resistivities have been successfully deposited in place of β-Ta and β-W films. The insertion loss of resonator filters consisting Ta- or W-electrode/ST-90°X quartz has been improved by 1.5-8 dB using the α-Ta or the α-W film electrode.
Original language | English |
---|---|
Pages (from-to) | 3047-3049 |
Number of pages | 3 |
Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
Volume | 43 |
Issue number | 5 B |
DOIs | |
Publication status | Published - 2004 May |
Externally published | Yes |
Keywords
- Low loss
- Resistivity
- Resonator filter
- SH-LSAW
- α-phase metal film
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)