Composition-dependent structural, optical, mechanical, and moisture resistant properties of <inline-formula><roman>CaF</roman>_{<roman>2</roman>}<roman>-TiO</roman>_{<roman>2</roman>}</inline-formula> composite films prepared by reactive ion-assisted codeposition

Abstract

The influences of TiO 2 contents on the structural, optical, mechanical, and moisture resistant properties of CaF 2 -TiO 2 composite films prepared by reactive ion-assisted codeposition are systematically investigated. The CaF 2 films deposited at an ambient substrate temperature are found to have superior optical, mechanical, and moisture resistant properties with the addition of 10 at. % TiO 2 . The structure of this film changes from polycrystalline CaF 2 to a mixed phase of amorphous TiO 2 and polycrystalline CaF 2 . The hardness of composite films containing 45 at. % TiO 2 is even higher than that of pure TiO 2 and glass, which is attributed to the isolation of the crystalline CaF 2 grains by the interconnection of the amorphous TiO 2 dispersoids. © 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)