Performances of phase-change recording disks based on GaSbTe media

Phase-change optical disks with novel GaSbTe recording media were prepared in the DVD+RW format and evaluated by a dynamic tester at 1X speed. The studied compositions locate along the Sb7Te3-GaSb and Sb2Te3-GaSb pseudo-binary tielines. The disks were prepared by an RF co-sputtering method. Enhanced recrystallization has been demonstrated in the disks with Sb7Te3 -rich recording layer. An approximated composition Ga2Sb5Te3 even exhibited a nearly complete erasure (CNR similar to 45 dB, de erasability similar to -40 dB). Relationship between the dynamic characteristics and crystal structure of the GaSbTe materials has been proposed.