Abstract

Phase-change optical data storage is basically based on the difference in optical properties between amorphous and crystalline phases of a recording medium. It has been known that the physical properties including reflectance and thermal conductivity of a material basically depend on the chemical composition of materials and their microstructure. Lately, the manipulation of chemical composition in GeSbTe-based chalcogenide that is one of the most promising candidate materials for phase-change recording medium was tried by doping a small amount of nitrogen in Ge-Sb-Te phase-change optical disks^[1] From the earlier work, an enhanced media cyclability was achieved in PPM recording at the wavelength of around 780 nm. The goal of this research is to investigate the variation of thermal, optical and dynamic properties, and their correlation to microstructure in nitrogen-doped Ge₂Sb₂Te₅ phase-change recording media. Primary endeavors focused on the dependence of nitrogen doping on crystallization temperature, reflectance, initializing power level, CNR and overwrite jitter at the wavelength of 650nm and pulse-width modulation (PWM) recording, leading to higher storage density.

© 1998 Optical Society of America