Development of ALD TiO2 Layers for Application in III-IV-Silicon Cells for Direct Water Splitting

During my master thesis I will work on the development of titanium dioxide (TiO2) thin films for application as an anti-corrosion layer for III-V/Silicon photoelectrochemical cells. Due to the specific nature of its application, this layer should not only protect the semiconductor structure from chemical degradation, but also show suitable optical (low absorption/ reflection) and Electrical (High conductivity/ Low Contact Resistance to AlInP) characteristics. Using Atomic Layer Deposition (ALD) the structure and chemical composition of the TiO2 films can be carefully controlled down to the sub nanometer scale, this level of control is required when even minor changes in composition/ layer thickness/ structure can lead to significantly different film properties. Using Characterization techniques such as XRD, XPS and SEM the impacts of crystallinity and composition will be analyzed and adjusted to allow the optimized design of the TiO2 protective coating.