The effect of temperature on nonisothermal crystallization kinetics and surface structure of selenium thin films

In this work, the crystallization kinetics of Se thin films has been studied under nonisothermal conditions using a differential scanning calorimetric (DSC) technique. The analysis focuses on the effect of temperature (385 K <= T <= 418 K) on the DSC results. Two methods were used to determine the variation of the activation energy for crystallization E, with temperature. It was found to change from 69 +/- 4 kJ mol(-1) down to 23 3.2 kJ mol(-1) and from 83 3.3 kJ mol(-1) down to 55 2.5 kJ mol(-1) for results obtained using the Friedman and Kissinger-Akahira-Sunose methods, respectively. The effects of annealing were revealed by studying the morphology of the samples using scanning electron microscopy and atomic force microscopy. The Johnson-Mehl-Avrami and Prout-Tompkins models have been used for the description of DSC crystallization data. It seems that two-dimensional growth is the most probable mechanism of the crystallization, particularly at high temperature. (c) 2006 Elsevier B.V. All rights reserved.