High-speed retardation modulation ellipsometer.
Construction and performance of a high-speed retardation modulation ellipsometer are described. An ADP four-crystal electrooptic modulator is used for the retardation modulation and a high-speed digitizer for the simultaneous detection of the transmitted light intensity and the modulation voltage. The ellipsometer can acquire the necessary data for determining a data point (Psi, Delta) in 4 microsec and repeat the data acquisition for fifty data points at intervals of 4 microsec-160 msec. In such conditions, precision represented in terms of an average of root mean squares is 0.05 degrees in Psi and 0.15 degrees in Delta when a BaK1 standard optical glass is used as a sample at the present stage. An example is given of the application to rapid growth of anodic films on a semiconductor GaAs wafer.
Moritani
A
A
Osaka University, Department of Electronic Engineering, Suita, Osaka 565, Japan.
Okuda
Y
Y
Kubo
H
H
Nakai
J
J