Crystallographic characteristics and effective electromechanical coupling coefficients of AlN thin films for FNAR applications

Author

Kim, G.H. ; Keum, M.J. ; Seo, H.I. ; Park, D.S. ; Lee, I.B. ; Kim, K.H.

Author_Institution

Dept. of Electr. & Inf., Kyungwon Univ., Seoul, South Korea

Volume

2

fYear

2003

fDate

5-8 Oct. 2003

Firstpage

2020

Abstract

In this study, AlN thin films for film bulk acoustic wave resonator (FBAR) device applications were investigated using facing targets sputtering system (FTS) and a DC power supply. The crystallographic characteristics, c-axis preferred orientations, and effective electromechanical coupling coefficients (K₂^eff) of such AlN thin films were characterized by varying N₂ gas flow ratio [N₂/(N₂+Ar)] from 0.6 to 0.9 and a substrate temperature from room temperature to 300°C. The optimal processing conditions for AlN thin films were found to be an N₂ gas flow ratio of 0.6 and a substrate temperature of 200°C at a sputtering power of 200 W and a working pressure of 1mTorr. In these conditions, we obtained the c-axis preferred orientation of AlN/Al/SiO₂/Si thin film about 4 degree.

Keywords

acoustic resonators; aluminium compounds; bulk acoustic wave devices; piezoelectric thin films; sputter deposition; substrates; 1 mTorr; 200 C; 200 W; AlN; AlN thin films; Ar; DC power supply; N₂; SiO₂; crystallographic characteristics; electromechanical coupling coefficients; facing targets sputtering; film bulk acoustic wave resonator; gas flow ratio; sputtering power; substrate temperature; Acoustic waves; Crystallography; Film bulk acoustic resonators; Fluid flow; Power supplies; Sputtering; Substrates; Temperature; Thin film devices; Transistors;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics, 2003 IEEE Symposium on

Print_ISBN

0-7803-7922-5

Type

conf

DOI

10.1109/ULTSYM.2003.1293314

Filename

1293314