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Multiplexed extrinsic silicon detector array
Multiplexed extrinsic silicon detector arrays for infrared applications were developed and tested. Cryogenic electronics are discussed. Ambient temperature electronics are also discussed.
The response of a 300 micron silicon detector to monoenergetic neutrons determined by the use of the Monte Carlo technique
The response of a 300 micron thick silicon detector to an incident monoenergetic neutron beam is evaluated by the Monte Carlo method for the cases of both a shielded and a bare detector. The result of Monte Carlo calculation, using elastic, inelastic, and absorption reactions indicates that the response of the silicon detector to neutrons is basically due to the elastic scattering. In addition, the gamma rays generated in the shield of the detector will result in a response which is 3 or 4 orders of magnitude smaller than response to incident photons. The response of a bare silicon detector is calculated for neutron energies up to 6 MeV and bias energies from 50 to 250 KeV. It is found that the maximum response for a 300 micron thick silicon detector is less than .004 c/n within this selected neutron and bias energy range. When the pulse height defect is introduced in the calculation the results at low energy neutrons were reduced.
Heavy-particle studies with silicon detectors
Response of lithium-drifted silicon detectors for radiobiologic applications
Heavy-particle studies with silicon detectors.
Response of lithium-drifted silicon detectors to high energy alpha and proton beam and radiobiologic application
Fluctuations of energy loss by heavy charged particles in silicon detectors - Preliminary measurements.
Thick lithium drifted semiconductor silicon detectors for investigation of fluctuations of energy loss by high and intermediate energy particles
Fabrication methods for lithium drifted surface barrier silicon detectors.
Fabrication methods for lithium drifted surface barrier silicon detectors, discussing lithium diffusion, stain etching, preparation for and final etch
Thin-film scintillators for extended ultraviolet /UV/ response silicon detectors
The preparation and radiometric properties of silicon detectors coated with fluorescent thin films are described. The films are deposited from solutions of clear plastics, such as acrylic resins, polyvinyl toluene or polystyrene, and of organic laser dyes in a common solvent. They are optically clear, mechanically and chemically stable, yet easily applied and removed. Multiple doped films of a few microns thickness exhibit broad-band absorption from less than 250 nm to about 450 nm and narrow band emissions with peaks ranging from 380 nm to 600 nm. Internal quantum efficiencies are close to 100 percent and fluorescence decay times are in the nanosecond range. When deposited on optically denser media, a large fraction of the fluorescent emission is trapped in the substrate. Silicon photodiodes coated with multiple doped films exhibit high external quantum efficiencies and virtually flat photon response in the near UV.
Further characterization of IRAS doped silicon detectors
Measurements made on several doped-silicon detectors are reported. Topics discussed include: Si:Sb detector, the effects of detector bias on dielectric relaxation; characterization of spontaneous noise and gamma-induced spikes and their circumvention; and the time response of two detectors to step changes in the background photon flux density. Several potential system programs are indicated.
Vacuum UV performance of silicon detectors
The sensitivity, time-varying response, and spatial sensitivity of four silicon detectors of vacuum UV were measured by passing a typical flux of 3 x 10 photons/s at the Lyman alpha line of 1215.7 A through an exit aperture of 0.55 mm x 0.8 mm. The detectors tested were: (1) a Fairchild FPM 200 silicon planar passivated photodiode with the window removed so that radiation could directly impinge on the center of the 1.0 mm square silicon chip, (2) a Fairchild FPM 100 silicon NPN planar passivated phototransistor, (3) the Hewlett-Packard 5082-4204 silicon planar PIN photodiode, and (4) the United Detector Technology PIN Spot/2 special sensitive silicon Schottky surface photodiode with the window removed.
Two-Dimensional Position-Sensitive Silicon Detectors for the ACE Solar Isotope Spectrometer
Two-dimensional position-sensitive silicon detectors (matrix detectors) have been designed, procured, and tested as part of the development of the Solar Isotope Spectrometer (SIS) instrument for NASA's Advanced Composition Explorer (ACE) mission. Important characteristics of these devices include: thickness approx. 50-90µm, active area 34 cm 2 , 64 strips on each surface with 1 mm strip pitch.
Stellar photometric data for six different photocathode materials and the silicon detector
Stellar photometric data for six photocathode materials and silicon detector
The response of a 0.03-cm silicon detector to a mixed neutron and gamma field as a function of shield material and thickness
The neutron and gamma radiation from a MHW-RTG was used to evaluate the total response of a shielded 0.3-mm silicon detector. The generator employs a 2200 W(th) PuO2 heat source concept known as the HELIPAK. The total integrated neutron and gamma ray fluxes at 100 cm away from the source along the radial direction were 1.67 x 1,000 n/sq cm/s and 1.49 x 10,000 gamma sq cm/s, respectively. Experimental values of the response function of the shielded silicon detector were used to determine the total counting rates due to photons at bias energies ranging from 50 to 200 keV. For neutrons, analytically computed response functions were used to determine the total counting rates at the same bias energies. It was found that for an aluminum shield the neutrons are not significant, regardless of the thickness of the shield. However, the magnitude of the total counting rate due to neutrons increases with increased atomic number of the shield and becomes comparable to the counting rate due to photons for a platinum shield thickness of 5 cm.
Fluctuations of energy loss by charged particles in silicon detectors
Fluctuations of energy loss by charged particles in lithium-drifted silicon semiconductor detectors
High-energy neutron spectroscopy with thick silicon detectors
The high-energy neutron component of the space radiation environment in thick structures such as the International Space Station contributes to the total radiation dose received by an astronaut. Detector design constraints such as size and mass have limited the energy range of neutron spectrum measurements in orbit to about 12 MeV in Space Shuttle studies. We present a new method for high-energy neutron spectroscopy using small silicon detectors that can extend these measurements to more than 500 MeV. The methodology is based on measurement of the detector response function for high-energy neutrons and inversion of this response function with measured deposition data to deduce neutron energy spectra. We also present the results of an initial shielding study performed with the thick silicon detector system for high-energy neutrons incident on polyethylene.
Silicon detector measurements of energy deposition in aluminum by monoenergetic electrons
Silicon detector measurements of energy deposition in aluminum by monoenergetic electrons
Advanced Silicon Detectors for High Energy Astrophysics Missions
A viewgraph presentation on the development of silicon detectors for high energy astrophysics missions is presented. The topics include: 1) Background: Motivation for Event-Driven CCD; 2) Report of Grant Activity; 3) Packaged EDCCD; 4) Measured X-ray Energy Resolution of the Gen1 EDCCDs Operated in "Conventional Mode"; and 5) EDCCD Gen 1.5-Lot 1 Planning.
Stellar photometric data for six different photocathode materials and the silicon detector.
Photodetector responses to radiant energy from many stars tabulated for various photocathode materials and silicon detector