Rapid Intense Pulse Light Sintering of Copper Sulphide Nanoparticle Films

Copper sulphide (Cu_xS, x = 1 to 2) is a metal chalcogenide semiconductor that exhibits useful optical and electrical properties due to the presence of copper vacancies. This makes Cu_xS thin films useful for a number of applications including infrared absorbing coatings, solar cells, thin-film electronics, and as a precursor for CZTS (Copper Zinc Tin Sulphide) thin films. Post-deposition sintering of Cu_xS nanoparticle films is a key process that affects the film properties and hence determines its operational characteristics in the above applications. Intense pulse light (IPL) sintering uses visible broad-spectrum xenon light to rapidly sinter nanoparticle films over large-areas, and is compatible with methods such as roll-to-roll deposition for large-area deposition of colloidal nanoparticle films and patterns. This paper experimentally examines the effect of IPL parameters on sintering of Cu_xS thin films. As-deposited and sintered films are compared in terms of their crystal structure, as well as optical and electrical properties, as a function of the IPL parameters.