Semiconductor Physics, Quantum Electronics & Optoelectronics. 2011. V. 14, N 3. P. 273-278.
Polarization conversion effect in obliquely deposited SiOx films
1V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine,
45, prospect Nauky, 03028 Kyiv, Ukraine
Abstract.
Structural anisotropy of the SiOx films and light emitting
nanostructures, prepared by oblique deposition of silicon monoxide in vacuum, has been
studied using the polarization conversion (PC) effect. For this purpose, a simple method
of PC investigation with usage of a standard null-ellipsometer is proposed and tested.
This method is based on the analysis of the azimuthal angle dependence of the off-
diagonal elements of the Jones matrix. The electron microscopy study shows that
obliquely deposited SiOx nc-Si-SiOx films have a porous (column-like) structure with the column
diameter and inclination depending on the deposition angle. Polarimetric investigations
revealed that both in-plane and out-of-plane anisotropy was present, which is associated
with the columnar growth. The correlation between the PC manifestations and the
scanning electron microscopy results is analyzed. It was found that the tilt angle of
columns in obliquely deposited SiOx is smaller than that predicted by the “tangent rule”
and “cosine rule” models, and depends on the crystallographic orientation of Si substrate.
It is concluded that the proposed method is effective non-destructive express technique
for the structural characterization of obliquely deposited films.
Keywords: polarization conversion, ellipsometry, anisotropy, oblique deposition, silicon
oxide, nanostructure, microstructure.
|