145 research outputs found
Investigation of the detectivity of radiation- produced defect levels in n and p type silicon and germanium Semiannual progress report
Black body responsivity data of n-type and p-type silico
Thin wire pointing method
A method is described for forming sharp tips on thin wires, in particular phosphor bronze wires of diameters such as one-thousandth inch used to contact micron size Schottky barrier diodes, which enables close control of tip shape and which avoids the use of highly toxic solutions. The method includes dipping an end of a phosphor bronze wire into a dilute solution of sulfamic acid and applying a current through the wire to electrochemically etch it. The humidity in the room is controlled to a level of less than 50%, and the voltage applied between the wire and another electrode in the solutions is a half wave rectified voltage. The current through the wire is monitored, and the process is stopped when the current falls to a predetermined low level
Composite metal-oxide device has voltage sensitive capacitance
Device with step function variation of the capacitance is useful for voltage-controlled oscillator circuits and as a voltage-sensitive switch. Simplicity of construction makes the device suitable for large-scale integration, microelectronic circuits
A Study on the Effects of C060 Gamma-radiation on Steam-grown Sio2 MOS Structures
Cobalt 60 gamma radiation effects on Metal Oxide Semiconductors /MOS/ with p-type and n-type silicon substrate
Frequency shifting with a solid-state switching capacitor
Frequency shifting, commonly used in electronic signal processing, is applied in tuning, automatic frequency control, antenna element switching, phase shifting, etc. Frequency shifting can be accomplished economically and reliably with simple circuit comprising conventional resistor and solid-state switching device which can be equivalent to two capacitors, depending on switching state
Fabrication and optimization of a whiskerless Schottky barrier diode for submillimeter wave applications
The following accomplishments were made towards the goal of an optimized whiskerless diode chip for submillimeter wavelength applications. (1) Surface channel whiskerless diode structure was developed which offers excellent DC and RF characteristics, reduced shunt capacitance and simplified fabrication compared to mesa and proton isolated structures. (2) Reliable fabrication technology was developed for the surface channel structure. The new anode plating technology is a major improvement. (3) DC and RF characterization of the surface channel diode was compared with whisker contacted diodes. This data indicates electrical performance as good as the best reported for similar whisker contacted devices. (4) Additional batches of surface channel diodes were fabricated with excellent I-V and reduced shunt capacitance. (5) Large scale capacitance modelinng was done for the planar diode structure. This work revealed the importance of removing the substrate gallium arsenide for absolute minimum pad capacitance. (6) A surface channel diode was developed on quartz substrate and this substrate was completely removed after diode mounting for minimum parasitic capacitance. This work continues with the goal of producing excellent quality submillimeter wavelength planar diodes which satisfy the requirements of easy handling and robustness. These devices will allow the routine implementation of Schottky receivers into space-based applications at frequencies as high as 1 THz, and, in the future, beyond
Investigation of the detectivity of radiation- produced defect levels in n- and p-type silicon and germanium Final report
Spectral results of p- and n-type silicon and germaniu
Tables of f/us, ub/ and g/us, ub/ functions for semiconductor surface calculations
Derivation of mathematical functions for calculating changes in semiconductor surfaces due to applied surface charg
A New Mass Spectrometer
A new type of mass spectrometer has been constructed in which no magnetic fields are used. By applying an alternating electric field at right angles to the beam of positive particles all but certain velocities are removed from the beam. Because of the fact that a symmetry not contemplated in the theory previously published was introduced in the construction for mechanical reasons, the apparatus transmits some other velocities besides those desired. This produces extra peaks and complicates the mass spectrum. Because of this and the fact that the apparatus is badly contaminated with mercury from the diffusion pumps in spite of the continued use of liquid air, we have designed a new apparatus in which, it is expected, both effects will be eliminated. Comparison of the peak at 32 with that at 34 gives a maximum ratio of the intensity of O_(16)O_(16) to O_(16)O_(18)+Hg^(6+)_204 of 300. This is presumably the ratio with the smallest contamination of mercury and means that the ratio of O_(16) to O_(18) is greater than 600
Effect of tensor couplings in a relativistic Hartree approach for finite nuclei
The relativistic Hartree approach describing the bound states of both
nucleons and anti-nucleons in finite nuclei has been extended to include tensor
couplings for the - and -meson. After readjusting the parameters
of the model to the properties of spherical nuclei, the effect of
tensor-coupling terms rises the spin-orbit force by a factor of 2, while a
large effective nucleon mass sustains. The overall
nucleon spectra of shell-model states are improved evidently. The predicted
anti-nucleon spectra in the vacuum are deepened about 20 -- 30 MeV.Comment: 31 pages, 4 postscript figures include
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