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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Forward biased asymmetric p-n junction diodes with arbitrary impurity distributions, measuring minority carrier lifetimes by refined step recovery technique
Magnetically coupled tunnel diode oscillator with square loop core, calculating leakage and source inductances effect on switching pattern
Capacitance voltage measurements on interface of pyrolytically deposited n-type silicon dioxide- InAs MOS diodes as function of admittance at room and 77 K temperatures
Open loop transient analysis of thermionic diode kinetics experiment with analog computer nuclear reactor simulator
Computer acquired performance mapping of fixed spaced planar diode with etched Re emitter and Nb collector over wide operating temperature range
Design, fabrication and testing of electrically heated externally configured thermionic diodes with emitter using mandrel side of CVD fluoride tungsten for electrode surface
P-i-n avalanche diode trapped plasma avalanche triggered transit /TRAPATT/ oscillations characteristics and voltage waveform under square wave driving current, using computer program
Thermal noise in space charge limited solid state diodes with field dependent mobility and hot carriers
Self consistent one dimensional large signal analysis of Read type IMPATT diode oscillator, taking into account device-circuit interaction
Noise, admittance and I-V characteristics of hot holes in space charge limited Ge diodes at high voltage and frequencies to 22 MHz
Computer acquired I-V characteristics of thermionic fixed spaced planar diodes
Circuit which includes a thermistor-resistor combination to compensate for temperature fluctuations by supplying input voltage to light-emitting diode, maintains constant light output. Similar circuits can be used for temperature-induced variations in photodiode applications.
Diode-quad bridge circuit was developed for use with pressure-sensitive capacitive transducers, liquid-level measuring devices, proximity deflection sensors, and inductive displacement sensors. It may also be used as FM discriminator and as universal impedance bridge.
Performance data from an etched-rhenium, molybdenum thermionic converter are presented. The planar converter has a guard-ringed collector and a fixed spacing of 0.254 mm (10 mils). The data were acquired by using a computer and are available on microfiche as individual or composite parametric current, voltage curves. The parameters are the temperatures of the emitter T sub E, collector T sub C and cesium reservoir T sub R. The composite plots have constant T sub E, and varying T sub C or T sub R, or both. The envelope and composite plots having constant I sub E are presented. The diode was tested at increments between 1500 and 2000 K for the emitter, 750 and 1100 K for the collector, and 540 and 640 K for the reservoir. In all, 774 individual current, voltage curves were obtained.
Eight different types of cermet seals for thermionic diodes were investigated: (1) 1 micron Al2O3 with Nb spheres; (2) 200 A Al2O3 with Nb spheres; (3) 1 micron Al2O3 with Nb 1% Zr spheres; (4) 200 A Al2O3 with Nb 1% Zr spheres; (5) Pure Y2O3 with Nb 1% Zr spheres; (6) Y2O3 3% ZrO2 with Nb 1% Zr spheres; (7) Y2O3 10% ZrO2 with Nb 1% Zr spheres; and (8) ZrO2 12% Y2O3 with Nb 1% Zr spheres. Investigations were made to determine the most favorable fabrication techniques and the effect of the bonding cycle, (length of bonding time and shutdown sequences). The analysis of the seals included tensile test, vacuum test, electrical test and metallurgical examination. At the conclusion of the development phase, 36 seals were fabricated for delivery for evaluation.
Indexes and summaries of the conference papers containing cesium-diode results are presented. Lists of converter materials, geometries, conditions, outputs, and lifetimes accompany the references. Simple chemical designations for emitters, collectors, and additives direct the reader to appropriate selections.
GaAs IMPATT diodes with plated heat sinks are shown to be particularly well suited for microstrip circuit applications. Details of materials growth and device fabrication procedures are given, and experimental results are presented for a GaAs IMPATT microstrip oscillator operating at X band.
Improved temperature compensation of the output from a GaAs LED can be obtained by connecting the diode in series with the emitter of an n-p-n transistor whose base circuit incorporates a high-gain operational amplifier and a parallel thermistor-resistor network. The temperature dependence of several photodiodes is also reported along with a practical temperature compensation scheme. Finally, the temperature compensation of a photon coupled pair consisting of a GaAs LED and a silicon photodiode is described. The combination provides a stability, linearity, and repeatability of about 1% over the upper 60% of the LED forward current range in the temperature interval from 15 to 45 C.