Amorphous thin gallium arsenide films have been evaporated by flash evaporation technique with thickness of about 3500 ?, under vacuum of about 10-6 mbar, on ultrasonically cleaning corning glass substrate, at substrate temperature 423 K. GaAs films have been irradiated by continuous Ar+ ion laser with power nearly 120 mW for different duration times. X-ray diffraction of the as prepared and irradiated GaAs films is amorphous structure. The optical properties of GaAs films were investigated by studying the infrared and ultraviolet spectra and some optical constants were founded and compared before and after irradiation, the absorption edge shift toward the longer wavelengths (red shift) after irradiation process with respect to the as deposited film, the value of the absorption coefficient for GaAs films at the absorption edge has decreased slightly after irradiation process by factor of about 4. The direct optical energy gaps of GaAs films were estimated to be 1.78 eV for the as prepared decrease to 1.52 eV after irradiation process.
A. Abdullah, Rasha; L. Matar, Faleh; A. Razooqi, Mohammed; and S. Jassim, Awatif
"The Effect of Photo irradiation by Low Energy Laser on the Optical Properties of Amorphous GaAs Films,"
International Journal of Thin Film Science and Technology: Vol. 2
, Article 2.
Available at: https://digitalcommons.aaru.edu.jo/ijtfst/vol2/iss1/2