Swift heavy ion induced growth of nanocrystalline silicon in silicon oxide

Abstract

Recystallization of nanocrystalline silicon in silicon oxide has been initiated with swift heavy ion irradiation. 100 MeV Ni ions from pelletron were used for irradiating the thin films of silicon oxide (SiOx) at fluences varying from 1×1012 to 5×1013 ions/cm2. Phase separation between silicon and silicon oxide is seen to be responsible for the photoluminescence spectrum peaking around 350 and 610 nm. This spectral nature is understood on the basis of defects and interface states in SiOx matrix and silicon nanocrystals, respectively. The formation of silicon nanocrystals resulting from the phase separation has been confirmed from the complimentary evidence of change in the refractive index, Fourier transform infrared spectroscopy, and energy despersive x-ray analysis. High electronic loss associated with the 100 MeV Ni ions is thought to be responsible for the recrystallization, and rearrangement of silicon.