Refractive-index change caused by electrons in amorphous AsS and AsSe thin films doped with different metals by photodiffusion

Influence of ultraviolet-light exposure on electron-beam written gratings in amorphous As–Se thin films coated with different metals

“…[2][3][4][5][6] The diffusion is dependent on the metal and it changes physical parameters of ACh. 6 Therefore, it is very important to know which kind of metal layer is used on ACh when it is exposed with electrons. As a rule the function of the metal layer is to conduct the electrons away to prevent the sample charging.…”

“…The direct written gratings were read with a low-power HeNe laser ͑wavelength ϭ633 nm͒ and the analysis of the results was done as previously. [6][7][8] Figure 1 shows an example of the effect of the UV-light exposure given before the grating writing. Figure 1 gives the difference of the phase shift of the two samples with the Au layer on top as a function of the electron dose.…”

“…This is due to the fact that Au atoms/ions do not diffuse with electrons and the phase shift detected is caused by electron-induced alterations in the film. 6 Increase of can be detected when the film is exposed with UV light before the EBL exposure.…”

“…Ag atoms/ions diffuse willingly into film with electrons creating a concentration gradient of Ag between exposed and unexposed areas. 6 When electron irradiation is stopped this concentration gradient tends to smooth because of the thermal relaxation. The mobility of Ag is so high that lateral diffusion destroys the grating modulation.…”

Thermal annealing effect on the optical properties of Ag10As30S60 thin film

“…Refractive-index [11,12], and undoped and silver photodoped AsS amorphous thin films [13] have been studied. However, studies on the optical properties of the Ag doped AsS thin films changes as the variation of thermal annealing conditions are still required.…”