Characterization of evaporated Cr-SiO cermet films for resistive-gate CCD applications

The films were evaporated from power sources of different Cr-SiO compositions. Auger electron spectroscopy depth profiling was carried out to measure the uniformity of the cermet composition. Electrical conduction in the cermet films was measured at temperatures ranging from 50 to 370 K, before and after annealing. The electrical characteristics of cermet/GaAs Schottky diodes were measured and compared to those of Cr/GaAs and Al/GaAs diodes. The I-V characteristics of the diodes before annealing were almost the same; however, annealing the cermet/GaAs diode at 425 degrees C for as short a time as 45 s reduced reverse leakage current by nearly two orders of magnitude, producing better Schottky diode characteristics than those of annealed Al and Cr Schottky diodes. The effects of rapid thermal annealing on the cermet/GaAs diodes and cermet films was investigated. A resistive-gate GaAs CCD delay line was fabricated and tested to demonstrate the performance of the evaporated Cr-SiO cermet as a resistive material.<
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