Electrical phase change of Ga:La:S:Cu films

Ga:La:S:Cu films have been prepared by sputter deposition. Amorphous thin films were fabricated with Cu concentrations as high as 66 at.%. The electrical phase change properties of these films have been investigated. The electrical resistivity of these materials is 200 Omegam in the amorphous state and 40 Omegam in the crystalline state. The crystallisation time was measured using an optical pump probe method and confirmed to be 150 ns. The high resistivity of these films in both their crystalline and amorphous states allows low current, Joule, heating and therefore shows potential for the utilisation as the active layer in electrical phase change memory devices.