[Photograph 2012.201.B1095.0288]

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Roberts, Jim - (R) Edmond - Sen. 41 candidate

Transmission electron microscopy (TEM) characterisation of Ru2Si3 thin films formed by solid state reaction of Ru and Si

Transmission electron microscopy investigation on Ru2Si3 thin films formed by solid state reaction of Ru and Si revealed a top layer of SiO2 with embedded Ru clusters. We attribute the formation of the top layer to the oxidation between residual oxygen traces in the nitrogen and the silicon in Ru2Si3 grains. The observation is in agreement with electrical measurements. In addition, an interlayer, which has complex structure and chemistry, was observed between the film and substrate

Transmission electron microscopy (TEM) characterisation of thermally grown RuO2 thin films

RuO2 thin film fabricated by rf- sputtering from a pure Ru target and subsequently oxidized at 600C 30 minutes under O2/N2 gas was studied by transmission electron microscopy (TEM). The un-oxidized Ru grains are found at the bottom of the film in broken segments; whereas the oxidized RuO2 grains are found on top of the Ru grains but are frequently in direct contact with the SiO2 layer. The observations partially support the work function measurement of such films in a previous study

Defect generation in non-nitrided and nitrided sputtered gate oxides under post-irradiation Fowler-Nordheim constant current stress

Metal oxide semiconductor (MOS) capacitors were fabricated with nitrided and non-nitrided sputtered oxides. The MOS structures were exposed to 2 Mrad gamma-ray dose and stored in a dry ambient for one year. Post-irradiation stability of MOS capacitors was investigated by applying Fowler-Nordheim constant current stress and monitoring the positive charge, border traps and interface states generation. It was found that nitridation increased the resistance of sputtered oxides to various defects generation under irradiation, electrical and combined radiation-electrical stress. The improved stability is explained in part by compensation of oxygen vacancy defects and Pb centers by nitrogen. (C) 2012 Elsevier B.V. All rights reserved

N-channel polysilicon thin film transistors as gamma-ray detectors

N-type thin film transistors (TFTs) fabricated with fluorinated and hydrogenated polysilicon were exposed to gamma radiation to a cumulative dose up to 1200 Gy(Si). During irradiation, the gate electrode was biased with a positive voltage up to 4.8 V. The effect of irradiation on the electrical characteristics of the devices was monitored after the irradiation steps and in a prolonged period after irradiation. The main monitoring parameter was the threshold voltage which was found to have linear dependence on irradiation dose. This, together with obtained low fading, suggests that thin transistors have potential as radiation dosimeters