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Polycrystalline diamond films produced by Microwave Plasma Enhanced Chemical Vapor Deposition were investigated for use as dielectric material for advanced passive devices needed in pulsed power applications. CVD diamond films that were heat treated in air from 250°C to 450°C for 2hrs. had very steady dielectric constants, ranging from 5 to 6.5, and very low losses, less than 0.005, over 100 to 106Hz at room temperature. Dielectric constants varied by less than 5% with temperature cycling to 500°C and losses remained very low (less than 0.01). Resistivities of CVD diamond heat treated in air were two to three orders of magnitude higher than the as-deposited samples. Breakdown strength, I-V and charge-discharge characteristics were also measured. Surface termination was examined to explain differences in the electrical performance of heat treated and as-deposited CVD diamond.

Thin barium titanate(BT), lead zirconate titanate(PZT), barium strontium titanate(BST) films are being developed for use in microelectronics, electromechanical and optoelectronic applications. Thin BaTiO3, Pb(ZrTi)O3 and (BaSr)TiO3 film capacitor devices were fabricated using RF sputtering techniques. The typical dielectric constant of these film capacitors was in the range of 300 to 1140. These film capacitors had dissipation factors between 0.2% to 0.6 % before annealing and 4-6% after annealing. The film capacitors have breakdown voltages in the range of 1×105 V/cm to 1.2×106 V/cm. The resistivity was in the range of 1010 to 1012 ohm-cm before annealing and 1013 to 1014 ohm-cm after annealing. The capacitance of films produced to-date had little dependence on frequency. Thermal cycling in the temperature range of 50 to 300°C had very limited impact on the capacitance and dissipation factor. Measurements of dielectric and material properties are reported.