Comparative study on TeO2 and TeO3 thin film for γ-ray sensor application

Tellurium trioxide (TeO3) and tellurium dioxide (TeO2) thin film has been deposited by rf sputtering. The influence of gamma-radiation doses (in the range 10-50 Gy) on the optical and electrical properties of as-deposited films were studied. Optical band gap values were found to decrease with increasing radiation dose whereas electrical conductivity was increased by about five orders in magnitude. Monotonic decrease in the values of dielectric constant for the deposited TeO3 films with increase in radiation dose was observed. The gamma-ray response behavior of TeO3 and TeO2 thin films are compared, and TeO3 thin film is found to be more suitable in amorphous form for gamma-ray detection.