LIU Feng-juan, HU Zuo-fu, LI Zhen-jun, ZHANG Xi-qing. Surface Acoustic Wave Based on ZnO Thin Films Grown by RF-MBE[J]. Chinese Journal of Luminescence, 2012,33(3): 328-333
LIU Feng-juan, HU Zuo-fu, LI Zhen-jun, ZHANG Xi-qing. Surface Acoustic Wave Based on ZnO Thin Films Grown by RF-MBE[J]. Chinese Journal of Luminescence, 2012,33(3): 328-333 DOI: 10.3788/fgxb20123303.0328.
Surface Acoustic Wave Based on ZnO Thin Films Grown by RF-MBE
High quality ZnO piezoelectric thin films have been grown by RF-MBE on sapphire (0001) substrate with MgO and ZnO double buffer layers. Only ZnO (0002) diffraction peak was observed in the XRD patterns
with a narrow FWHM of 0.10. A sharp absorption peak and a steep absorption edge were observed in absorption spectra
only one PL peak from free exciton emission
with a narrow FWHM of 12.7 nm
was obtained in PL spectra. The electrical resistivity of the ZnO thin films is up to 410
7
cm. These results indicate that ZnO thin films have good
c
-axis orientation with wurtzite structure
low defect densities and low background carrier concentration. This is mainly due to that the MgO and ZnO double buffer layers accommodated the mismatch between the ZnO thin films and the sapphire substrate. The SAW devices based on the high quality ZnO thin films were fabricated. The center frequency of the surface acoustic wave (SAW) filter is 835 MHz
and the SAW propagation speed is up to 5 010 m/s
indicating that the MgO and ZnO double buffer layers not only improved the quality of the ZnO films
but also improved the piezoelectric properties of the films.
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references
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