Solution process for fabrication of thin film CdS/CdTe photovoltaic cell for building integration

A low-cost, scalable chalcogenide semiconductor thin film deposition process, Chemical Bath Deposition, is used to fabricate semi-transparent TiO2/CdS/CdTe solar cells. Cadmium telluride (CdTe) acts as an absorber and cadmium sulphide (CdS) is the window layer with band gaps of 1.45 eV and 2.45 eV, respectively. In this work, about 400 nm thick p-CdTe and ~ 200 nm n-CdS films are deposited on titanium dioxide (TiO2) coated substrate. Insertion of TiO2 layer at front contact between FTO coated glass substrate and CdS; improved CdS/CdTe PV cell performance by reducing the leakage current. This resulted in increase of short circuit current in the device. At the initial stage of development the cell exhibits a voltage of 100.53 mV and photocurrent of 14.7 mA/cm2, illustrates the potential of the process. The devices are characterized using FE-SEM, UV-Visible spectroscopy, XRD and AFM. The fabricated PV cells are around 43% transparent and these semi-transparent cells can be used as windowpanes for building integrated photovoltaic applications.