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Charge transport in steam-grown thin films of silicon dioxide (SiO2) is studied using a short-duration pulse of energetic electrons for generating hole-electron pairs in the oxide. Within the time resolution of the measuring circuitry ( approximately 1 ns) electron transport follows the excitation pulse exactly. It is shown that electron-beam-induced currents in SiO2 are limited by geminate or columnar recombination processes and that the incorrect application of the normal photoconduction equation to experimental data leads to invalid thickness-dependent mobility-lifetime products ( mu tau ). The present measurements indicate that for electron mu tau >>1.2*10-13 m2 V-1 and mu >1.2*10-4 m2 V-1 s-1.

A novel approach is used, for the first time, for the determination of both thickness (d) and refractive index (n) of Cu2O thin film using thermal and optical interferometry techniques. This approach results in more reliable values of these two parameters than the values obtained by using conventional spectroscopic techniques. This approach can also be extended to obtain the values of d and n for other thin films.

A pulsed electron beam is used to generate electron-hole pairs in SiO2 films and the yield measured as a function of temperature and applied voltage. It is shown that over the temperature range 200 to 400K the electron yield is controlled by an initial recombination process.

Silicon and Silicon-Tellurium films were prepared in an ultrahigh vacuum system. The d.c. electrical conductivity of these films were measured under vacuum before exposing them to the air. The thermal activation energies of Silicon-Tellurium films were always found to be greater than that of Silicon films. Furthermore the optical measurements on Silicon-Tellurium films indicated that the optical gap of these films decreases as the concentration of tellurium in the films increases. Electron microscope examinations revealed that the films were amorphous in structure and homogeneous in composition.