The effect of film composition on the texture and grain size of CuInS/sub 2/ prepared by spray pyrolysis

Ternary single-source precursors were used to deposit CuInS/sub 2/ thin films using chemical spray pyrolysis. We investigated the effect of the film composition on texture, secondary phase formation, and grain size. As-grown films were most often In-rich. They became more (204/220)-oriented as indium concentration increased, and always contained a yet unidentified secondary phase. The (112)-preferred orientation became more pronounced as the film composition became more Cu-rich. The secondary phase was determined to be an In-rich compound based on composition analysis and Raman spectroscopy. In addition, as-grown Cu-rich (112)-oriented films did not exhibit the In-rich compound. Depositing a thin Cu layer prior to the growth of CuInS/sub 2/ increased the maximum grain size from /spl sim/ 0.5 /spl mu/m to /spl sim/ 1 /spl mu/m, and prevented the formation of the In-rich secondary phase.