Ultrafast Al(Si)-induced crystallisation process at low temperature

Abstract

Aluminium-induced crystallisation process can be accelerated by a factor of about 50 by the doping of Si atoms into the initial Al layer. This process is known as Si-AIC (aluminium-induced crystallisation). The grain size and crystallographic orientation of the grown poly-Si thin film produced are modified due to the fact that the presence of excess Si in the initial Al layer alters the nucleation and growth behaviour of the Si grains as compared with the traditional AIC process. In the present study, the nucleation mechanism and growth rate of Si grains for Si-AIC are analysed and quantitatively compared with those for AIC using time-series transmission electron microscopy/energy-dispersive X-ray spectroscopy (TEM/EDS) images. It is found that the activation energy for grain growth was significantly reduced in the Si-AIC process, by 0.7 eV compared with the AIC process.