Cadmium telluride thin films: growth from solution and characteristics

An extremely simple and cheap method for the deposition of cadmium telluride thin films is presented. Good quality deposits were obtained on ground glass at 75 degreesC, pH 10 +/-0.3 with a deposition time of 90 min. Light grey-coloured and uniform CdTe layers, approximately 0.3 mum thick, were obtained with this process under the above deposition conditions. Compositional analysis showed CdTe films to be Cd-rich. The as-deposited layers are crystalline with a mixture of hexagonal and cubic phase structures. Microscopic observations showed some overgrowth on the spherical-type crystallites grown. Baking increases the coarseness of the material compared to the as-deposited film. Optical studies revealed a high absorption coefficient (10(4) cm(-1)) with a direct type of transition. The band-ap is estimated as 1.45 eV. The films show n-type conduction. (C) 2001 Elsevier Science B.V. All rights reserved.