Influence of ion assistance on the optical properties of MgF(2).
The optical properties of MgF(2) films prepared by evaporation and ion-assisted deposition have been determined from transmittance and near-normal incidence reflectance measurements and also from electron-energy loss spectroscopy (EELS). The results show that oxygen-ion assistance leads to higher extinction coefficients for wavelengths <180 nm. Transmission electron microscopy studies show that the crystal grain size of MgF(2) films is not strongly affected by oxygen or argon-ion bombardment. The presence of MgO in the films is inferred from RBS measurements and proposed to be the major factor influencing VUV losses. EELS is also demonstrated to be a valuable technique for determination of optical properties from the near-infrared to x-ray regions of the spectrum.
Martin
P J
PJ
Sainty
W G
WG
Netterfield
R P
RP
McKenzie
D R
DR
Cockayne
D J
DJ
Sie
S H
SH
Wood
O R
OR
Craighead
H G
HG