Thin films of yttrium sesquioxide, Y2O3, have been deposited on Si by ion b
eam sputtering at room temperature and 700 degreesC under an oxygen pressur
e of 4 x 10(-3) Pa or by oxygen ion beam assisted deposition. The stoichiom
etry of these films was analysed by Rutherford backscattering spectrometry.
The thickness and refractive index of the oxide were studied as functions
of the wavelength by ellipsometry. The crystalline orientations of the depo
sited films were determined by x-ray diffraction. The micro- and nano-struc
ture were investigated by transmission electron microscopy on cross section
samples.