The role of oxygen content in the crystallization kinetics of (Sb0.90Ge0.10)Ox films

The differences between the crystallization kinetics arising from the incorporation of oxygen have been studied in a material of interest for phase-change optical storage (antimony-rich SbyGe1-y films). The crystallization process of (Sb0.90Ge0.10)Ox films, with x varying within the 0.10-0.16 range, has been observed during in situ isothermal annealing in a transmission electron microscope. The results show that the crystal growth mechanism is the same as for antimony-rich SbyGe1-y films regardless of oxygen content, but higher crystal growth velocities are observed. Some changes in the nucleation process occurring for the highest-oxygen-content films are discussed. The initial relaxation state has been found to influence the crystallization kinetics of these films, with relaxation resulting in a decrease in the minimum crystallization temperature and in the nucleation rate.This work has been partially supported by Cornision Interministerial de Ciencia y Tecnologia (Spain) under the TIC93-0125 project and by the British Council and the Spanish Government under the Acciones Integradas scheme. We are grateful to the Royal Society for financial support (A.K.P.L.) and to the Materials Modelling Laboratory in the Department of Materials at Oxford for image-processing facilities