Abstract
A (112̄0)-plane epitaxial ZnO film is deposited on an R-plane (011̄2)-plane) sapphire substrate. In order to generate a shear bulk wave using the ZnO film, metal electrodes are required at both planes of the ZnO film; namely, the top plane on the top surface of the ZnO film and the bottom plane at the boundary between the ZnO film and the R-sapphire substrate. A c-plane ((0001)-plane) polycrystal ZnO film is conventionally deposited on the metal film on the R-sapphire substrate. Thus, the (112̄0)-plane epitaxial ZnO film for the shear bulk transducer has not been realized until now. The authors realized a (112̄0)-plane epitaxial ZnO film with low electrical resistivity (ρ of the order of 10-4 Ω·cm) on an R-sapphire substrate by doping with an impurity such as Al, Ga, or V as a substitute for the metal electrode, and a (112̄0)-plane piezoelectric epitaxial ZnO film with high electrical resistivity (ρ > 10+10 Ω·cm) on this epitaxial ZnO film with low electrical resistivity for fabricating a shear wave transducer. An Al electrode was deposited on the piezoelectric ZnO film. By using the Al electrode as the top-plane electrode and a (112̄0)-plane epitaxial ZnO film with low electrical resistivity as the bottom-plane electrode substituting for the metal film, strong shear bulk waves have been generated.
| Original language | English |
|---|---|
| Pages (from-to) | 3281-3284 |
| Number of pages | 4 |
| Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
| Volume | 41 |
| Issue number | 5 B |
| DOIs | |
| Publication status | Published - 2002 May |
| Externally published | Yes |
Keywords
- (112̄0)-plane ZnO film
- Epitaxial ZnO film
- R-sapphire
- Shear bulk wave
- Transducer
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)