Synthesis of CdTe microstructures on p-type silicon (111) using light-modulated electrodeposition

In this paper, we present the results of our electrodeposition experiments of cadmium telluride (CdTe) microstructures on p-type silicon (111) spatially modulated by the incidence of light. This technique has shown itself to be practical and inexpensive, with immediate results. The construction from an adequate microcell to the process and all the required methodologies by such a technique are also shown. Photoelectrodeposition allows the creation of localized microdeposits, since the type of substrate used is activated locally by focalized light incidence. The photoelectrodeposited samples were characterized by optical profilometry and scanning electron microscope (SEM). The profilometry analyses showed that the deposit dimensions are directly proportional to the incident laser power but are not significantly influenced by the exposure time. The SEM has revealed information regarding the size and the concentration of the clusters on the deposited regions. The size of these agglomerates is affected by the laser intensity, showing itself higher on the center of the deposits than on the peripheral regions. Both the size of the clusters and their concentrations increase as the laser exposure time increases. Furthermore, higher concentrations of clusters are seen when linear polarization is used instead of circular polarization, but circular polarization generates larger clusters.