Title :
Surface acoustic wave bandpass filters properties of AlN thin films sputtered on LiNbO3 substrates
Author :
Kao, Kuo-Sheng ; Cheng, Chien-Chuan ; Chen, Ying-Chung ; Chen, Chien-Hsing
Author_Institution :
Dept. of Electr. Eng., Nat. Sun Yat-Sen Univ., Kaohsiung, Taiwan
fDate :
28 May-1 June 2002
Abstract :
Surface acoustic wave (SAW) filter properties such as center frequency (Fc) and 3dB bandwidth of aluminum nitride (AlN) thin films sputtered on z-cut LiNbO3 substrates were investigated. Highly c-axis prefer-oriented AlN thin films deposited on z-cut LiNbO3 substrates were obtained by reactive rf magnetron sputtering. The results of our experiments showed that Fc of SAW filter was increased significantly for the increase of h/λ, where h was the AlN film thickness and λ was the wavelength of SAW. Comparing the SAW propagate along with the z-cut LiNbO3 single crystal, the AlN/LiNbO3 based surface acoustic wave (SAW) devices could improve the velocity of SAW. The 3dB bandwidth of SAW filter was decreased by the increase of h/λ meaning that frequency selection getting stricter.
Keywords :
III-V semiconductors; aluminium compounds; band-pass filters; lithium compounds; piezoelectric semiconductors; piezoelectric thin films; semiconductor thin films; sputtered coatings; surface acoustic wave filters; wide band gap semiconductors; AlN; AlN thin films; LiNbO3; LiNbO3 substrates; SAW filters; frequency selection; sputtered; surface acoustic wave bandpass filters; Acoustic waves; Aluminum nitride; Band pass filters; Bandwidth; Frequency; Magnetic separation; SAW filters; Sputtering; Substrates; Surface acoustic waves;
Conference_Titel :
Applications of Ferroelectrics, 2002. ISAF 2002. Proceedings of the 13th IEEE International Symposium on
Print_ISBN :
0-7803-7414-2
DOI :
10.1109/ISAF.2002.1195953
