Optical absorption studies in molybdenum trioxide thin films

Abstract

Thin films of molybdenum trioxide are prepared by the electron beam evaporation technique onto glass substrates maintained at temperatures in the range 303 to 523 K. The effect of substrate temperature and oxygen partial pressure on the structure and optical properties of MoO3 films is investigated. The as-deposited films show α-β mixed phase. Both the films formed at 523 K in an oxygen partial pressure of 26.6 × 10−3 Pa and the films formed at 523 K and heat treated in air exhibit the orthorhombic α-phase with optical band gap 3.25 and 3.2 eV, respectively.