Formation and modifications of nanostructures of tin oxide by SHI irradiation

Abstract

We deposited thin films of tin oxide (SnO₂) by the thermal evaporation method on quartz and Si substrates. The as-deposited films were irradiated using 100 Mev Ag ions at different fluences ranging from 1×10¹² to 1×10¹³ ions/cm². Pristine and irradiated films were characterized for surface topographical study using atomic force microscopy. Pristine films on both types of substrates (Si and Quartz) are featureless. Irradiation at the lowest fluence (1×10¹² ions/cm²) induces the nanostructures at the surface and higher fluence irradiations change the shape and size of these nanostructures. The value of roughness and growth exponent, as evaluated from power spectral density analysis, indicates that the formation of nanostructures is mainly due to the swift heavy ion-induced surface diffusion process. We have tried to explain the results in the framework of the thermal spike model.

Keywords:

• SnO₂
• nanostructures
• PSD analysis
• SHI irradiation
• roughness exponent