The surface quality is crucial for growth of epitaxial layers on III–V semiconductor substrates. In this work the procedures of epi-ready semi-insulating (SI) GaAs wafer preparation were developed. The atomic force microscopy (AFM), triple crystal X-ray diffraction (TCD) and X-ray photoelectron spectroscopy (XPS) were used to monitor morphology and composition of substrates with different chemical treatment history. We propose an optimised epi-ready SI GaAs wafer preparation procedure involving NH4OH:H2O2:H2O/NaOCl:H2O2:H2O etching/polishing.
Source:Institute of Electronic Materials Technology