The electronic and optoelectronic device technology of III-V semiconductors is based on the growth of complex multilayer structures. The integration of III-V compounds with silicon substrates benefits from the cost-effective and mature Si technology and the outstanding (opto-)electronic properties of III-V semiconductors. A good candidate for heteroepitaxy on Si is GaP, since it is almost lattice-matched to Si. In our team, we utilize angle-resolved X-ray photoelectron spectroscopy (XPS) in combination with gas cluster ion beam (GCIB) etching and synchrotron-based hard X-rays photoelectron spectroscopy (HAXPES) for investigation of atomic and electronic properties of GaP/Si heterostructures and buried heterovalent interfaces. Schematic picture of experimental techniques is shown in figure below. The experimental measurements are supported by an initio DFT calculations and photoelectron intensity simulations.
Interface of GaP/Si heterostructure