Browsing by Author "Stiegler, Harvey J."

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    An electron-beam controlled discharge laser o the C-->A transition of xenon fluorite
    (1985) Stiegler, Harvey J.; Wilson, William L.; Tittel, Frank K.; Sauerbrey, R. A.
    A XeF(C->A) laser utilizing an electron-beam controlled electric discharge for excitation was investigated. Studies were made of He, Ne, and Ar as buffer gases with various combinations of NF, F2, and Xe. The partial pressure of the various gas components was varied to find a mixture which would achieve optimum performance. Energy deposition by the discharge was confirmed by observing the intensity of fluorescence. Positive optical gain was achieved for a duration of 3 ns to 4 ns and a peak gain of > 1% cm was measured. Spectral narrowing and gain sufficient to overcome cavity losses were evidence of laser action. Output observed from the laser was on the order of 1 uJ/liter of active volume. Performance was limited by inability to rapidly deposit sufficient energy into the discharge. The possibility of a longterm absorption phenomenon related to the electric discharge may also have limited performance.
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    Electrical and thermal modeling of electrostatic discharge protection structures for submicron VLSI
    (1989) Stiegler, Harvey J.; Wilson, William L., Jr.
    A modeling technique has been developed which simulates a semiconductor device subjected to electrostatic discharge (ESD) stress according to the human body model (HBM). To accomplish this, a computer program was developed which solves the electron and hole continuity equations, Poisson's equation, and the heat flow equation in one dimension. The program has been applied to npn structures typical of the parasitic bipolar devices found in MOS output stages. Profiles from lightly-doped drain (LDD), double-diffused drain (DDD), and graded drain (GD) device structures were investigated. The performance of these various profiles under ESD stress has been compared in order to understand their functioning and to determine the important design parameters. It is found that device heating is reduced for structures in which the doping profile rises steeply to a high concentration in the drain region near the metallurgical junction. The rate of heating is related to reduced carrier saturation velocity due to local heating and its effects on charge distribution, electric field, and total potential drop across the reverse-biased junction. The modeling technique presented gives results which are in reasonable agreement with measured data. This technique should be a useful tool for evaluating new device structures, fabrication processes, or process changes before committing to the costly and time-consuming process of actual device fabrication.