Chalcogenide Letters Vol. 9, No. 3, March 2012, p. 121 - 126 COMPARISON OF PROPERTIES OF CADMIUM, COPPER AND LEAD SULFIDES THIN FILMS GROWN BY CBD A. G. ROJAS-HERNÁNDEZ a* , T. MENDÍVIL-REYNOSO b,c , M.C. ACOSTA- ENRÍQUEZ a , R. RAMÍREZ-BON d , S.J. CASTILLO b a Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-088, CP. 83000, Hermosillo, Sonora, México b Departamento de Física, Universidad de Sonora, Apdo. Postal 1626, CP. 83000 Hermosillo, Sonora, México. c Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial. CP 31109 Chihuahua, Chih., México. d Centro de Investigación y Estudios Avanzados del IPN. Unidad Querétaro, Apdo. Postal 1-798, C.P. 76001, Querétaro, Qro., México In this work we are presenting a comparative study of Cd, Cu and Pb sulfides thin films grown by Chemical Bath Deposition technique, the as ground films were polycrystalline for the Cd and Pb Sulfides while the Cu sulfide was amorphous. The Atomic Force Microscopy images gave us information about the representative surface morphology and roughness, being RMS PbS =15.3nm, RMS CdS =3.2nm, RMS CuS =30.4nm. We used UV-Vis Spectroscopy to determine simple optical responses, getting the biggest transmittances of 45% for PbS, 72% for CdS and 80% for CuS, and direct energy band gaps of 2.37 eV for CdS and 1.26 eV for CuS. We use X-rays Photoelectrons Spectroscopy to formalize the chemical composition analysis, from this analysis we could to proof the high purity of the chemical bath deposition method in the materials preparation. (Received February 24, 2012; Accepted March 20, 2012) 1.Introduction Thin films have attracted the attention of researchers for their potential optoelectronic applications. Especially the PbS, and CdS have a direct narrow gap semiconductor. In the case of PbS, it is very suitable for infrared detection applications due to have a energy band gap of approximately 0.37–0.4 eV at room temperature [1,2]. This material has also been used in many fields such as photography [3], Pb2+ ion selective sensors [4] and solar absorption [5-7]. The CdS has been used in the manufacture of solar cells because it has an energy band gap in the 2.42 to 2.45 eV, interval, it is one promising II-VI compound materials because of its wide range of applications in various optoelectronics, piezo electronic and semi conducting devices. It is used in CdTe devices as an optical window. However, poor conductivity as low as (10.8 m) -1 have been reported. CuS thin films of the present case have been found to be of poor crystallinity or even amorphous. It may, however be possible to bring in crystallinity and to convert these films into the more desirable chalcocite phase by introducing copper ions/atoms into them [8]. In [9] it is showed a amorphous nature of thin film and indirect transition with a bandgap of 1.28 eV. CuS is a well-known material because of its opto-electronic properties. Precipitate-based copper sensitive ion-selective electrodes use a membrane prepared by pressing a disk of * Corresponding autor: arojas@cifus.uson.mx