PRELIMINARY STUDIES OF THE USE OF ON AUTOMATED FLOW-CELL ELECTRODEPOSITION SYSTEM FOR THE FORMATION OF CDTE THIN-FILMS BY ELECTROCHEMICAL ATOMIC LAYER EPITAXY

This paper is the first report of the formation of thin films, thicker than ten monolayers, using electrochemical atomic layer epitaxy (ECALE). Thin films of CdTe have been electrodeposited on polycrystalline gold substrates in an electrochemical thin-layer flow-cell deposition system using the ECALE methodology. Studies of the deposit morphology have been performed using scanning electron microscopy and atomic force microscope. Significant improvements in deposit morphology are reported as a result of changes to the ECALE cycle program and deposition hardware. Deposit compositions analyzed using electron probe microanalysis and inductively coupled plasma atomic emission spectrometry, were found to be stoichiometric and nearly independent of the number of cycles and the Cd deposition potential. In addition, the deposition rate was shown to be one CdTe monolayer per cycle (half monolayer of Cd and half monolayer of Te per ECALE cycle).