Comprehensive Study of Growth Mechanism and Properties of Low Zn Content Cd1-xZnxS Thin Films by Chemical Bath

作者：Anibal Rodriguez Carlos; Guadalupe Sandoval Paz Myrna; Saavedra Renato; Trejo Cruz Cuauhtemoc; De la Carrera Francisco; Aragon Luis E; Sirena Martin; Delplancke Marie Paule; Carrasco Claudia

来源：Materials Research, 2016, 19(6): 1335-1343.

DOI：10.1590/1980-5373-MR-2015-0660

• Cd1-xZnxS
• chemical bath deposition
• optical properties
• structural properties

Cd1-xZnxS thin films have been studied extensively as window layers for solar cell applications. However, a mismatch between the Cd1-xZnxS and copper-indium-gallium-selenide absorber layers increases with Zn film concentration, which reduces the device efficiency. In this work, Cd1-xZnxS thin films with low Zn concentrations were analyzed. The effect of the addition of different molar Zn concentrations to the reaction mixture on the growth mechanism of Cd1-xZnxS thin films and the influence of these mechanisms on structural, optical and morphological properties of the films has been studied. Cd1-xZnxS thin films were synthesized by chemical bath deposition using an ammonia-free alkaline solution. Microstructural analysis by X-ray diffraction showed that all deposited films grew with hexagonal structure and crystallite sizes decreased as the Zn concentration in the film increased. Optical measurements indicated a high optical transmission between 75% and 90% for wavelengths above the absorption edge. Band gap value increased from 2.48 eV to 2.62 eV, and the refractive index values for Cd1-xZnxS thin films decreased as the Zn increased. These changes in films and properties are related to a modification in growth mechanism of the Cd1-xZnxS thin films, with the influence of Zn(OH)(2) formation being more important as Zn in solution increases.

• 出版日期2016-12