This paper explores the electrodeposition of thick CdTe semiconductor layers. The electrodeposition of films up to 130 mu m thick has been achieved under optimized potential and current-controlled conditions in acidic aqueous solutions. The layers were characterized by scanning electron microscopy in order to investigate the morphological and compositional evolutions of the deposited material during the growth. Progressive enrichment in tellurium content, with the formation of an intermediate amorphous cadmium ditelluride phase and morphological transitions from dense to columnar structure, have been observed. These thickness-dependent properties have been compared to those observed with thin films as a function of the applied potential. Current-controlled conditions were also tested and allowed films of up to 130 mu m to be obtained, but still with a columnar structure. These results are discussed in terms of growth mechanisms. (c) 2007 The Electrochemical Society.