METHOD OF FORMING A THIN FILM

A method of forming a thin film of material on a surface of a substrate, the substrate comprising a semiconductor, comprises: depositing a thin film of metal on the surface of the substrate, wherein the deposition is performed in an ultra-high vacuum, and wherein the substrate is at a temperature of less than or equal to 260 K during the deposition. Cooling the substrate during deposition of the thin film of metal may allow for an atomically flat and very uniform thin film to be obtained. Also provided is a device obtainable by the method.