Journal Article

Impact of irradiation doses on the structural, morphological, and linear–nonlinear optical properties of Ge10Sb25Se65 thin films for optoelectronic applications

Alagarasan, D., Naik, R., Ganesan, R., Sahoo, D., Varadharajaperumal, S.

2022

Overview

In this study, we have reported proton irradiation (30 keV) induced various properties change in the thermally evaporated Ge 10 Sb 25 Se 65 films. The bulk sample was prepared by the melt-quenching method, and the thin films were prepared from the bulk sample by the thermal evaporation technique. The proton ions were bombarded on the Ge 10 Sb 25 Se 65 thin films at different fluences. The amorphous nature of the ion irradiated films was confirmed from the X-ray diffraction (XRD), and Raman spectra showed the essential information regarding the changes in peak intensity. Atomic force microscopic study revealed an abrupt increase in surface roughness of the irradiated films. However, significant variations were not observed from the field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopic analysis (EDAX). The fluence-induced dispersion, dielectric, and linear–nonlinear optical quantities were evaluated using the UV–Vis spectroscopy data. The increase in optical bandgap was observed, whereas their corresponding refractive indices decreased upon increasing the irradiation fluence. The increase in transmittance also suggests a reduction in the refractive index. The changes in absorption coefficient (α) and extinction coefficient (k) led to the changes in other linear and nonlinear parameters. The dispersion parameters, dielectric parameters, and plasma frequency decreased upon increasing the proton irradiation. SRIM-2008 software was used to analyse the electronic stopping power (S e ), nuclear stopping power (S n ), lateral straggling, longitudinal straggling, and the proton penetration range (R p ) in the Ge 10 Sb 25 Se 65 films. The dominating nature of S e compared to the S n was observed from this analysis. Conclusively, the behaviour of proton-irradiated Ge 10 Sb 25 Se 65 thin films widens the application possibilities in optoelectronic devices. Graphical abstract The influence of 30 keV proton ion irradiation on the surface morphology and surface topography (FESEM and AFM images) of Ge 10 Sb 25 Se 65 thin films. The irradiation influenced the linear and the nonlinear optical parameters.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Absorptivity / Annealing / Applied and Technical Physics / Atomic / Bulk sampling / Complex Systems / Condensed Matter Physics / Dispersion / Emission analysis / Energy / Evaporation / Field emission microscopy / Fluence / Glass substrates / Ion bombardment / Ion irradiation / Irradiation / Lasers / Mathematical and Computational Physics / Molecular / Morphology / Nonlinear optics / Optical and Plasma Physics / Optical properties / Optoelectronic devices / Parameters / Physics / Physics and Astronomy / Plasma frequencies / Proton irradiation / Raman spectra / Refractivity / Regular Article / Reinforced reaction injection molding / Spectrum analysis / Stopping power / Surface roughness / Theoretical / Thin films / X-ray diffraction