Diffraction-efficiency oscillations in amorphous As_2S_3 films

Photoinduced interdiffusion in nanolayered Se∕As2S3 films: Optical and x-ray photoelectron spectroscopic studies

“…We expect that As-As homopolar bonds exist only in the As 2 S 3 layer and not in the diffused region. Nordman et al 41 suggested that irreversible photostructural changes take place only at the strained sites ͑regions with homopolar bonds͒. So we assume that diffusion may take place through the strained sites.…”

“…The Se 2 0 /S 2 0 defects are known as annihilating defects ͑ADs͒. 41 It should be noted that diffusion takes place mainly in strained sites ͑where wrong bonds are close to Se 2 0 sites͒. During light irradiation, a decrease in photoinduced viscosity leads to a mechanical stress gradient and thus enables the directed motion of ADs.…”

Photo induced optical changes in Sb/As2S3 multilayered film and (As2S3)0.93Sb0.07 film of equal thickness

“…This means that even in a stoichiometric film such as As 2 S 3 , where the stoichiometry would only allow As-S bonds, a large number of so-called wrong bonds As-As, S-S are present. Spectroscopic studies on unannealed films have shown that irreversible band gap light-induced photostructural changes are mainly due to the photo induced As-As bond breaking (As-As being the weakest bond) followed by the phonon-assisted creation of As-S bonds [27]. 2As 3 0 +S 2 0 +h ↔ As 2 + + As 2 − + S 2 0 + phonon ↔ As 3 0 +S 3 + +As 2 − Here, the superscript indices designate the electric charge of atoms, and the subscript indices their coordination number.…”

“…This shifting of peak towards higher BE value indicates the formation of As-S bonds. During light irradiation, As-As bonds are broken and phonon-assisted As-S bond formation take place by using the lone pair electrons of S 2 0 [27]. From the spectra of As 3d peak (see Fig.…”

X-ray photoelectron spectroscopic studies on Se/As2S3 and Sb/As2S3 nanomultilayered film

“…[13]. During light irradiation, As-As bonds are broken and phonon assisted As-S bond formation take place by using the lone pair p electrons of S 0 2 [10,14]. If we compare the Sb4d BE (Fig.…”