ATHERMAL PHOTOAMORPHIZATION OF AS50SE50 FILMS

A novel process for producing amorphous state, namely photo-induced transformation, is reported in a chalcogenide material, As50Se50, which in the crystalline phase is a molecular solid consisting of As4Se4 molecules. The crystalline-amorphous transition is athermal. Although the mechanism of photo-induced transformation to the amorphous state is not known, two possibilities are suggested: either photon-induced intramolecular bond-breaking leading to a cross-linked CRN-like network, or intermolecular bond-breaking resulting in an orientationally disordered molecular glass.