The growth of gallium phosphide (GaP) crystals on silicon (Si) wafers, a critical step in the fabrication of advanced electronic devices, is often hindered by defects at the interface between the two materials. These defects, known as antiphase domain boundaries (APDs), arise from misalignments in the crystal structure due to atomic steps on the Si surface. A promising solution to minimize these defects is the use of arsenic (As) as a stabilizing agent for the Si surface, reducing the formation of APDs. We have studied the impact of As on the growth of GaP on Si wafers, analyzing the resulting GaP(As)/Si(100) heterostructures using X-ray photoelectron spectroscopy (XPS) in comination with Ar cluste ion beam sputtering. We revealed traces of As into the GaP lattice and localization of As at the heterointerface. We also revealed that valence band offsets (VBO), a measure of the energy difference between the valence bands of the two semiconductors with different band gaps, remained consistent at 0.6 electron volts, regardless of the doping type, miscut, or As termination of the Si substrate. These results highlight the influence of As on the electronic properties of the GaP(As)/Si(100) heterostructure, offering valuable insights for the development of more efficient and defect-free electronic devices.
