Growth of high quality Cu2ZnSnS4 thin films on GaN by co-evaporation

We report on the growth of high quality Cu
₂
ZnSnS
₄
(CZTS) thin films on GaN-on-sapphire (GOS) substrates by thermal co-evaporation. Structural characterization was performed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements. The results are compared to films grown by thermal co-evaporation on glass and those synthesized by the sulfurization of stacked precursors on glass. Our results show that single phase epitaxial quality CZTS films with improved crystallinity can be grown on GOS substrates. The optical and electrical properties such as optical transmission, carrier concentration and Hall mobilities of the films are also reported.