Title :
Preparation of AZO/ZnO/AZO/SiO2/Si thin film for FBAR
Author :
Kang, T.Y. ; Keum, M.J. ; Son, I.H. ; Kim, K.S. ; Lee, J.B. ; Kim, K.H.
Author_Institution :
Dept. of Electr. & Inf. Eng., Kyungwon Univ., Seoul, South Korea
Abstract :
In this research, zinc oxide (ZnO) piezoelectric thin films for film bulk acoustic resonator (FBAR) applications for a high frequency range were studied by use of FTS (facing target sputtering) system, which enables to provide high density plasma, a high deposition rate at a low working gas pressure, and high quality thin films. In order to improve the crystallographic property of ZnO thin films, an AZO (ZnO:Al thin film) bottom electrode which has an equal crystalline structure to a ZnO thin film was deposited on a SiO2/Si substrate. ZnO thin films were deposited at a different oxygen gas flow ratio, and various SiO2/Si substrate temperatures were tried at a 2mTorr discharge gas pressure and a 0.8A sputtering current. The film thickness and c-axis preferred orientation of ZnO thin films were measured by α-step and an x-ray diffraction (XRD) instrument. In the results, we could prepare the ZnO thin film with c-axis preferred orientation of 5° on substrate temperature 200°C at O2 gas flow rate 0.7.
Keywords :
X-ray diffraction; acoustic resonators; bulk acoustic wave devices; crystal properties; crystal structure; electrodes; piezoelectric thin films; sputtering; substrates; 0.8 A; 2 mTorr; 200 C; bottom electrode; crystalline structure; crystallographic property; density plasma; facing target sputtering; film bulk acoustic resonator; high frequency range; high quality thin films; low working gas pressure; oxygen gas flow; piezoelectric thin films; substrate; x-ray diffraction; Film bulk acoustic resonators; Fluid flow; Frequency; Piezoelectric films; Plasma applications; Plasma temperature; Semiconductor thin films; Sputtering; Substrates; Zinc oxide;
Conference_Titel :
Ultrasonics, 2003 IEEE Symposium on
Print_ISBN :
0-7803-7922-5
DOI :
10.1109/ULTSYM.2003.1293313
