Optical storage medium with reversible phase transitions - comprising tellurium-arsenic-germanium amorphous-crystalline layer on glass substrate

摘要

A reversible, optical recording medium is disclosed, with at least one substrate and at least one Te-As-Ge contg. storage layer of the phase transition type. The storage layer is formed from a Te-As-Ge alloy with a Ge content between 8 and 24 atomic % and an As content between 19 and 39 atomic %. A dielectric layer is deposited on at least one side of the storage layer. A reflection layer is deposited between the storage/dielectric layer system and the substrate, or on the side of the substrate opposite the layer system. The layers are formed by sputtering or evapn. ADVANTAGE - The device is highly sensitive, can be written to at temps. below 600 deg.C and erased in less than 300 ns. It has a high reflection contrast between the amorphous and crystalline states. The crystallisation temp. is above 1000 deg.C, so that stability of the recorded information is ensured over a long period of time.