A microstrip quarter wavelength ( lambda g/4) resonator in conjunction with a small probe is used to resolve objects with characteristic dimensions as small as a thousandth of the wavelength ( lambda g/1000). The characteristic length for the decay of the evanescent waves at the tip of the probe was measured to be approximately 100-150 mu m at a microwave frequency of 1 GHz ( lambda free approximately=30 cm). The authors applied this technique to map microwave conductivity of metallic lines on glass and printed circuit boards and to investigate conductivity variations across a silicon wafer. It was possible to detect holes in printed circuit boards that were covered with solder and were not detectable otherwise.

Elllpsometrlc measurements on plasma deposited "diamondIike" amorphous carbon (a-C:H) films were taken in the visible, (E -1.75 to 3.5 eV). The films were deposited on SI and their propertles were varied using high temperature (up to 750°C) anneals.The real (n) and Imaglnary (k) parts of the complex index of refraction N were obtained slmultaneously. Following the theory of Forouhl and Bloomer (Phys. Rev. B34, 7018 (1986)), a least squares fit was used to find the dispersion relations n(E) and k(E). Reasonably good fits were obtained, showing that the theory can be used for a-C:H films. Morever, the value of the energy gap Eg obtained in thls way was compared to the Eg. value using conventional Tauc plots and reasonably good agreement was obtained.

A novel technique based on the measurement of the frequency spectrum of the acoustoelectric current is used to determine the trapping time associated with dominant traps in p-type CuInSe(2). At room temperature, two trap levels with trapping time constant of 2x10(-4) and 6.7x10(-5) s are detected. Under white incandescent light, two more traps with trapping time constants of 1.4x10(-3) and 6x10(-4) s are detected. The minority (electron) and majority (hole) carrier mobilities in this material are also measured using the acoustoelectric technique, and they are 6+/-3 and 3.1+/-0.15 cm(2)/V-s, respectively. The hole carrier concentration was estimated to be around 5x10(15) cm(-3), and the surface of the sample was depleted.

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