INVESTIGATION ON THE STRUCTURAL AND OPTICAL PROPERTIES OF TIN OXIDE FILMS GROWN BY PULSED LASER DEPOSITION

Abstract

Thin tin oxide (SnO2) films have been grown on (001) SiO2 substrate by pulsed laser deposition (PLD) technique. XeCl laser was used for ablation of SnO2 ceramic targets at substrate temperatures ranging from room temperature to 500 oC and oxygen pressure in the range of 5 – 30 Pa. The structural and optical parameters of the layers have been studied as function of the deposition conditions. The oxygen pressure of 20 Pa was determined as an optimum one while the structural and optical properties vary with the substrate temperature. The film deposited at 500 oC and 20 Pa oxygen pressure has best crystalline properties, i.e. optimum growth conditions. However, film grown at 20 Pa and 200 oC has maximum transmission in the visible region. The refractive index of the film deposited at optimum growth conditions is 1.93, which is close to that of the bulk material (1.96). Moreover, film grown at 20 Pa and 400 oC has lowest (7 dB/cm) optical waveguide loss.