This work studies and presents an inner-interface trapping physical model for the ultra-thin ͑effective oxide thicknessϭ15 Å͒ zirconium oxide ͑ZrO 2 ͒ film to explain its hysteresis phenomenon. The shift of the capacitance-voltage characteristics swept from accumulation to inversion and then swept back with light illumination is about 110 mV, which is larger than the shift without light illumination ͑ϳ45 mV͒. The mobile ion effect is obviated using bias-temperature stress measurement. The proposed model successfully explains not only the phenomenon but also the thickness effect for the capacitance-voltage characteristics and the different turnaround voltages of the current density-voltage characteristics of the zirconium dielectrics.

Vapor-phase epitaxial growth of In0.53Ga0.47As lattice matched to (100) -oriented InP substrates is described, and the performance of photodiodes fabricated from this material is presented. Gas-flow conditions for lattice-matched growth with various Ga-CHl flows were established for growth using the hydride process. The effect of substrate temperature on gas-flow ratios necessary for lattice-matched growth was studied over the temperature range 650–750 °C. Growth rates were found to vary from about 8 to about 60 μm/h over this temperature range. The activation energy of surface reaction was determined to be 44 kcal/mole. Photodiodes fabricated from an InP/In0.53Ga0.47As/InP structure showed rise and fall times of ≲1 nsec with quantum efficiencies in excess of 95% at 1.22 μm.

Deep trapping centers in n-type InP samples grown by the liquid-encapsulated Czochralski, liquid-phase-epitaxial, and vapor-phase-epitaxial processes have been studied by photocapacitance techniques. Photocapacitance effects for Schottky barriers formed on these samples indicate four levels at 0.58, 0.78, 0.89, and 1.15 eV below the conduction band. Estimated trap concentration in various samples range from low-1014 cm−3 to the high-1012 cm−3. The broad increase in photocapacitance near 1.15 eV for all the samples may be associated with an intrinsic defect or phosphorus vacancy/impurity complexes. This result is consistent with the broadband present between 1.08 and 1.25 eV in photoluminescence experiments. The comparison between O2-doped and undoped VPE samples suggests the presence of oxygen located at about 0.78 eV below the conduction band in VPE material.

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The increased leakage current in InGaAsP APD’s near breakdown is found to be a rather uniform bulk property, not associated with conventional microplasmas, dislocations, or surface effects. Surface effects were eliminated by the fabrication of guard ring APD’s, but the increased leakage current persisted. Surface effects were further ruled out by a statistical study of the leakage current in a large sample of APD’s. The study shows conclusively that the leakage current is proportional to diode area, not perimeter.