Ys. Yoon et al., FABRICATION AND CHARACTERISTICS OF MICROELECTROMECHANICAL SYSTEM DEVICE BASED ON PZT FILMS AND SURFACE MICROMACHINING, Journal of the Korean Physical Society, 32, 1998, pp. 1760-1762
Microelectromechanical system processes based on surface micromachinin
g technique were studied to fabricate the electrical devices on silico
n wafer such as cantilever beam accelerometers and uncooled IR-detecto
rs. In recent, a short problem of the PZT film deposited by metalorgan
ic decomposition after fabricating processes made the device's failure
. In this article, solutions of this short problem and characteristics
of the PZT films before and after micromachining processes are studie
d to investigate the influence of device etching processes on the fina
l device characteristics. The remanent polarization values (at 15 V) o
f the PZT film on the Pt/Ti without processes and with processes are a
round 54 mu C/cm(2) and 28 mu C/cm(2), respectively. A possible simple
model for the decrease of polarization after etching processes will b
e suggested. Piezoelectric coefficient (at 4 V) measured by single bea
m laser interferometer, d(33) Of the PZT film on Pt/Ti and RuO2/Ru are
around 80 pm/V and 41 pm/V, respectively. The PZT films on the RuO2/R
u and Pt/RuO2 had almost the same remanent polarization and piezoelect
ric coefficient before and after etching process while the film on Pt/
Ti did not. These results suggest that the RuO2/Ru and Pt/RuO2 hybrid
conducting materials as a bottom electrode are good for MEMS based on
surface micromachining technique.