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

Abstract

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 Om in the amorphous state and 40 Om 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.

Refractive index and dispersion control of ultrafast laser inscribed waveguides in gallium lanthanum sulphide for near and mid-infrared applications

“…Chalcogenide glasses (ChGs) are an important class of materials used in phase-change memories [1], solar cells [2], sensors [3] and photonics [4]. They contain as their main constituent one or more of the chalcogen elements S, Se and Te, covalently bonded to network formers such as As, Ge, Sb, Ga, Si or P [4,5].…”

Phase Change Material Photonics

“…The earliest example of this concept was presented by the Zheludev group. They used the crystallisation of amorphous Gallium Lanthanum Sulphide [38] to control plasmonic split-ring resonators [35]. The same group also designed a series of Ge 2 Sb 2 Te 5 -based reconfigurable flat metasurface devices that refract and diffract light.…”

Influence of deposition parameters on composition and refractive index of femtosecond and nanosecond pulsed laser deposited gallium lanthanum oxysulphide

“…Electrically induced phase-change data-storage is reliant on the switching ability of the film, thus the material must be stable in its crystalline form and also have good glass-forming abilities. GLSO materials have proven to be switchable between their crystalline and amorphous phases [12].…”