TY - JOUR
T1 - Sc and Er Co-Doped AlN Surface Acoustic Wave Devices
AU - Mao, Shiping
AU - Ru, Zixiong
AU - Yang, Changtao
AU - Zhou, Jian
AU - Wu, Jianhui
AU - Fu, Yongqing
N1 - Funding information: This work was supported by the National Natural Science Foundation of China (NFSC No. 51605485). Engineering Physics and Science Research Council of UK (EPSRC EP/P018998/1) and Newton Mobility Grant (IE161019) through Royal Society and NFSC.
PY - 2022/11/22
Y1 - 2022/11/22
N2 - Co-doping AlN film with various elements of rare earth or transition metals has been considered as a good method to significantly improve its piezoelectric responses of surface acoustic wave (SAW) devices. In this paper, we investigated the influences of different Er/ Sc atomic percentage ratio on the piezoelectric and acoustic wave properties of the Er and Sc co-doped AlN films prepared by RF magnetron sputtering. Results show that c/a-axis ratio of the AlN films decreases after doped with Sc, whereas those of the AlN films codoped with Er and Sc increase as the Er/Sc ratio increases. The reasons can be explained from the competitions of Sc and Er elements for occupying the Al atoms sites, and the larger ion radius of the Er compared that of Sc, which causes significant increase of c/a. Resonant frequency and Rayleigh wave velocity of the SAW resonators fabricated using these co-doped AlN films decrease as the Er/Sc ratio increases. Electromechanical coupling coefficient (k2 eff) of the SAW devices increases after the AlN film is single doped with either Sc or Er element, but decreases after co-doping with both Er and Sc.
AB - Co-doping AlN film with various elements of rare earth or transition metals has been considered as a good method to significantly improve its piezoelectric responses of surface acoustic wave (SAW) devices. In this paper, we investigated the influences of different Er/ Sc atomic percentage ratio on the piezoelectric and acoustic wave properties of the Er and Sc co-doped AlN films prepared by RF magnetron sputtering. Results show that c/a-axis ratio of the AlN films decreases after doped with Sc, whereas those of the AlN films codoped with Er and Sc increase as the Er/Sc ratio increases. The reasons can be explained from the competitions of Sc and Er elements for occupying the Al atoms sites, and the larger ion radius of the Er compared that of Sc, which causes significant increase of c/a. Resonant frequency and Rayleigh wave velocity of the SAW resonators fabricated using these co-doped AlN films decrease as the Er/Sc ratio increases. Electromechanical coupling coefficient (k2 eff) of the SAW devices increases after the AlN film is single doped with either Sc or Er element, but decreases after co-doping with both Er and Sc.
KW - Er-Sc co-doped AlN film
KW - effective electromechanical coupling coefficient
KW - c/a-axis ratio
UR - http://www.scopus.com/inward/record.url?scp=85139439400&partnerID=8YFLogxK
U2 - 10.1080/10584587.2022.2102810
DO - 10.1080/10584587.2022.2102810
M3 - Article
SN - 1058-4587
VL - 230
SP - 171
EP - 178
JO - Integrated Ferroelectrics
JF - Integrated Ferroelectrics
IS - 1
ER -