Gradually Thermal Diffusing of Silver on Amorphous GeSe Thin Film; Structural and Optical Properties

Abstract Binary glasses of GeSe are prepared by melt quench technique. Two layers of thin film preparation have been done by the conventional thermal evaporation technique on glass substrate. GeSe with 340 ± 5 nm thickness is prepared as first layer, then thin silver layer are evaporated on top of the GeSe film. The GeSe with Ag on top of the film were annealed at different time of 30, 60, 90, and 180 and 210 min at 573 K of temperature. Subsequently, we have analyzed the films using scanning electron microscopy (SEM) and X-ray diffraction (XRD) to confirm the successful diffusion of Ag on GeSe films. XRD measurements show that as prepared Ag/GeSe have amorphous natures. Optical transmission and reflection spectra of the studied thin films are measured in the wavelength range of 200 − 2500 nm at room temperature. The optical properties of the new films were studied before and after annealing at different annealing times due to gradually thermal diffusing of Silver on GaAs. The absorption coefficient (α) as an optical constant is determined as a function of annealing times. Moreover, the values of the third-order nonlinear optical susceptibility increased with an increase of annealing temperatures due to gradually thermal diffusing of Silver. The results indicate that Ag/GeSe has great potential for various applications including optical sensors and optoelectronics.