Growth of CuInS2and CuIn5S8on Si(001) by the Multisource Evaporation Method

Thin films of CuInS2, CuIn5S8 and a mixture of these were epitaxially grown on Si(001) wafers at 400°C using a multisource evaporation method in which the In source temperature was varied. X-ray diffraction and reflection high energy electron diffraction observation showed that the CuInS2 film did not crystallize in the chalcopyrite structure, but in the Cu–Au structure with the c-axis normal to the substrate coexisting with the sphalerite structure. The CuIn5S8 film crystallized in the relaxed spinel structure with fairly good orientation. No evidence of CuIn3S5 was found from the X-ray diffraction patterns.