Characterization of the chemical bath deposited In(OH)xSy films: Effect of the growth conditions

The In(OH)xSy thin films were deposited by chemical bath deposition (CBD) using three different deposition procedures: ‘hot’: starting the deposition at 70 °C, ‘cold’: starting the deposition at room temperature and pre-treatment with In3+ ions prior the ‘hot’ deposition. The analysis of the deposited In(OH)xSy layers on glass revealed that modifications in the chemical bath deposition procedure provoked significant changes in the nucleation process, the growth rate, the layer elemental composition and the layer morphology. With an additional In3+ pre-treatment or starting from a cold solution, the formation of a dense bottom layer has been observed, resulting in In(OH)xSy films with more compact structure with refractive index values of 2.6. The comparison of the measured In/S ratio with a thicker layer suggests, that the In(OH)xSy deposition starts with an OH-rich layer. Assuming the indirect allowed band gap transition type, an Eg of 2.2 eV was found independent of the procedure type or deposition time.