GROWTH OF GAMMA-AL2O3 THIN-FILMS ON SILICON BY LOW-PRESSURE METAL ORGANIC-CHEMICAL VAPOR-DEPOSITION

Metal-organic chemical vapour deposition of Al2O3 using aluminium isopropoxide (Al(OC3H7)3) and nitrous oxide (N2O) via thermal pyrolysis was investigated with the goal of producing high quality Al2O3-p-Si(100) interfaces. From the X-ray diffraction analysis, the film was found to be a gamma-Al2O3 heteroepitaxial film. The stoichiometry of the grown Al2O3 film was similar to that of sapphire observed from Auger electron spectroscopy. Room temperature capacitance-voltage measurements clearly reveal metal insulator-semiconductor behaviour for samples with thc Al2O3 insulator gate, and the interface state densities at the Al2O3-P-Si heterointerface were approximately 10(11) eV-1 cm-2, at levels centred in the silicon energy gap.