MIXING KINETICS AND WRITE-ONCE OPTICAL-RECORDING CHARACTERISTICS OF SB SE BILAYER FILMS/

Bilayer Sb/Se films are irradiated with 12 ns pulses from an ArF laser (extended areas) and from a focused Ar+ laser (micron-sized areas). R eal-time reflectivity measurements are used to determine if the proces s occurs within the solid or liquid phase and the transformation time, in addition to measure the optical contrast and the medium sensitivit y. Transmission electron microscopy is used to analyze the structure o f the transformed areas and the medium resolution. The results show th at mixing is initiated by preferential melting at the grain boundaries and an amorphous phase is produced upon irradiation at high energy de nsities. Finally, the characteristics of the mixing process in Sb/Se f ilms as a write-once optical recording mechanism are discussed in term s of the sensitivity and resolution of the recorded spots and the time required for recording.