XPS, SEM and XRD investigations of CdSe films prepared by chemical bath deposition

Chemical bath deposition (CBD), a direct low cost technique that involves a cadmium salt solution, a complexing agent and a chalcogen source, was used to prepare CdSe semiconductor films. The most favourable conditions for acceptable quality CdSe films grown on glass were obtained. Commercially available microscope glass slides (with a size of 1 cm x 1 cm x 1 mm) were used as substrates to deposit CdSe films. CdSe films were deposited in a freshly prepared aqueous solution containing CdSO4 (0.2-0.4 M), NH4OH (3.8-14 M) as a complexing agent for slow release of Cd2+ ions, and Na2SeSO3 (0.118 and 0.16) as a source of Se2- ions. The solutions were prepared in deionized water. The glass slides were immersed in a mixture of CdSO4-NH4OH for 5 min before the solution of Na2SeSO3 was added. The bath temperature varied from 20 to 60 degrees C. Structural and morphological quality of the films was analyzed by XRD, SEM, EDS, and XPS. The results show that the crystallinity of the CdSe films as-deposited is improved by increasing temperature. The initial growth stages of CdSe films at 20 and 60 degrees C start on CdOx and Cd(OH)(2) buffer layers respectively. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.