Photoelectrical conversion using pn junctions based on transparent semiconductor oxides

Abstract

This master thesis focuses on thin film solar cells based on Transparent Conductor Oxide (TCO) that are able to generate an electric current while maintaining their transparency to visible light for photovoltaic and UV detectors applications. The studied heterostructure is based on Nickel Oxide (NiO), which is a new interesting material that exhibit an p-type behaviour, and Zinc Oxide (ZnO), a well-known n-type material subjected to many scientific researches in many fields. Moreover, dip-coating deposition technique is used in this master thesis to synthesised the heterojunction. This fabrication process is a soft chemical deposition technique where sol-gel solutions are used as precursors for the deposition. All the depositions are performed on a transparent glass substrate coated by a Fluorine Tin Oxide (FTO) thin film that plays the role of an ohmic back contact. Gold pads are deposited by sputtering on the top of the NiO (p-type side) to form the top contacts. The resulting heterostructure is characterised by different methods and the obtained I-V curves are compared to a simple analytical model.