SPECTROSCOPIC IDENTIFICATION OF THE SIO2 COMPLEX IN OXYGEN-IMPLANTED GAAS-SI

Oxygen-implanted and annealed GaAs:Si epitaxial layers have been inves tigated by low-temperature Fourier transform infrared absorption spect roscopy. Several new local vibrational modes are observed in the range from 614 to 641 cm(-1). Isotope shifts and splittings allow the unamb iguous chemical identification of the defect involved as SiO2. A micro scopic structure model is developed which provides, based upon a simpl e fit, the correct vibrational frequencies. Evidence is presented that deep levels associated with this complex are causing the high sheet r esistance of the layers.