SHI Irradiation Induced Amorphization Of Nanocrystalline Tin Oxide Thin Film At Low Temperature
R. S. Chauhan, Vijay Kumar, Anshul Jain, Deepti Pratap, D. C. Agarwal, R. J. Chaudhary, Ambuj Tripathi
Keywords: Tin oxide thin film; nanostructures; amorphization; pulsed laser deposition; swift heavy ion irradia
Nanocrystalline tin oxide (SnO2) thin films were fabricated using pulsed laser deposition (PLD) technique. The as-deposited films were irradiated at liquid nitrogen (LN2) temperature using 100 MeV Ag ions at different fluences ranging from 3×1013 to 3×1014 ions/cm2 and at 75º with respect to surface normal. Pristine and irradiated samples were characterized using XRD, AFM, Raman and I-V (current-voltage characteristics) for the study of modifications in structural, surface morphological, bond angle and resistivity respectively. XRD patterns show that the pristine film is highly polycrystalline and irradiation amorphizes the film systematically with increasing the irradiation fluence. The surface of the pristine film contains nanograins of tin oxide with roughness 5.2 nm. Upon irradiation at lower fluences agglomeration is seen and roughness increased to 10.8 nm. Highest fluence irradiation again develops nanograins with roughness 7.5 nm. Raman spectra and I-V characteristics also confirms the irradiation induced amorphization. The observed results are explained in the frame work of thermal spike model.