Formation of heterovalent interfaces: A combined photoemission and ab initio DFT study of GaP/Si heterostructures (GaP-Si)

Integration of III-V semiconductors on Si is desirable for new generation of microelectronic devices such as solar cells and photochemical diodes for high-efficient solar water-splitting. GaP is a potential candidate for transition layers from Si to other III-Vs heterolayers. Preparation of abrupt GaP/Si interfaces is the critical step in metalorganic chemical vapor deposition because it strongly impacts the quality of subsequently grown epitaxial films and the final device performance. Preparation of the abrupt GaP/Si interface remains an open question and interface formation mechanisms are not well understood at the atomic scale. In the bilateral project, a combination of optical in situ analysis, photoelectron spectroscopy techniques, depth profiling as well as ab initio density functional theory calculations will be carried out for an atomic-scale understanding of structural and electronic properties of GaP/Si heterointerfaces. The objective is to use the gained understanding for a specific control of the interfacial properties as desired by the final device concept.