The effect of dehydrogenation step on the nickel-induced crystallization of hydrogenated amorphous silicon

Abstract

This work investigates the nickel-induced crystallization (NIC) method for crystallizing hydrogenated amorphous silicon (a-Si: H) thin films on glass substrates. The a-Si: H samples are prepared using plasma-enhanced chemical vapor deposition at a temperature of 250 °C. Subsequently, thin layers of nickel are deposited on the a-Si: H films using DC magnetron sputtering. The resulting structures (Ni/a-Si: H/glass) are then subjected to annealing at 570 °C under an N2 atmosphere. Two annealing processes are compared: one involving a prior dehydrogenation step and the other without dehydrogenation. The impact of the annealing process on the crystallization of the amorphous films is investigated using X-ray diffraction, atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. The crystallinity of the samples is confirmed by X-ray diffraction and Raman spectroscopy. The results suggest that the dehydrogenation step may not be essential for achieving crystallization in hydrogenated amorphous silicon layers.