Bifacial photodetector using CZTS absorber material

This paper present a new “Bifacial photodetector” using CZTS absorber material. A device has been fabricated using fluorinated tin oxide (FTO) coated glass substrate. This substrate is utilized for growth of thin CZTS layer. CZTS layer was synthesized using electrodeposition of tri-layer stacks and subsequent elevated temperature sulfurization. Prior to device fabrication electrical characterization of CZTS thin film was performed. Results show a significant reduction of film resistance during illumination. A complete photosensor was fabricated using additional steps of CdS chemical bath deposition and subsequent ZnO sputtering. A Labview controlled system was used to monitor change in potential across photosensor terminal during illumination. It was observed that both front and rear illumination produces a potential increment when multiplied by Labview and a control board to illuminate a light emitting diode. This bifacial device can be more useful than a conventional photodiode as it provide more angular range for light signal detection.