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Self-healing breakdown techniques are employed to study dielectric breakdown in pyrolytic aluminum oxide films on silicon substrates. The Al2O3 is prepared by chemical vapor deposition at low temperature (300–600°C) using Al isopropoxide as source material. Both weak-spot breakdown and intrinsic breakdown in the absence of weak spots using Au–Al2O3–Si test capacitors are investigated. Intrinsic breakdown field strengths of 7.5×106 V/cm for Si+ on p-type substrates and 6.9×106 V/cm for Si − on n-type are observed and found to be independent of Al2O3 thickness and temperature. Weak-spot breakdown is found to be associated with contamination of the silicon surface.

Evaporated metallic contacts (area = 0.1 mm2) have been made to etched (100) surfaces of conducting strontium titanate single crystals. The metals employed were Mg, In, Au, Pd, and Pt. The electrical properties of these contacts were studied by measurements of: (1) differential capacitance as a function of bias voltage, (2) spectral variation of photoemission from the metal into the strontium titanate, and (3) current-voltage characteristics. The measurements have been analyzed to yield effective values of Δφ (work function of the metal with respect to the strontium titanate conduction band at the contact) with the following results: (1) the electrical properties of the contacts are different for the different metals, (2) the low-work-function metals (Mg and In) form low-resistance contacts, (3) the high-work-function metals (Au, Pd, and Pt) form blocking contacts, and (4) none of the blocking contacts can be characterized by a single value of Δφ; i.e., each blocking contact behaves as if it consists of patches of different Δφ.

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