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Theory, fabrication, and electric properties of lithium drifted silicon radiation detector with large sensitive volume
The ATIC balloon-borne experiment measures the energy spectra of elements from H to Fe in primary cosmic rays from about 100 GeV to 100 TeV. ATIC is comprised of a fully active bismuth germanate calorimeter, a carbon target with embedded scintillator hodoscopes, and a silicon matrix that is used as a main charge detector. The silicon matrix produces good charge resolution for the protons and helium but only a partial resolution for heavier nuclei. In the present paper a charge resolution of ATIC device was essentially improved and backgrounds were reduced in the region from Be to Si by means of the upper layer of the scintillator hodoscope that was used as an additional charge detector together with the silicon matrix. The flux ratios of nuclei B/C, O/C, N/C in the energy region from about 10 GeV/nucleon to 300 GeV/nucleon that were obtained from new high-resolution and high-quality charge spectra of nuclei are presented. The results are compared with existing theoretical predictions.
A quarter-meter diameter, modified Ritchey-Chretien camera is described for spacecraft-based observation of Halley's Comet. The system will operate over an unusually broad spectral region, from 0.1216 micron (the hydrogen Lyman-alpha line) to 1.1 microns using reflective primary and secondary mirror optics and a thin UV-grade lithium fluoride refractive element as a field corrector near the image plane. The f/12, 3000 mm focal length camera has a 0.4 deg full field of view for operation with a 15 x 15 mm charge-coupled device detector array. The UV-enhanced silicon CCD detector is a 1000 x 1000 array of 15 micron pixels which establishes the system resolution requirement. The optical design and performance are discussed, with an emphasis on the image analysis with respect to pixel resolution elements used for viewing extended objects such as comets.
This paper describes a type of cosmic ray detector suitable for the construction of a small, low power space-based instrument to detect the energy and isotope of energetic nuclei, such as those produced by solar flares. The detector is similar to previous types of silicon PIN detectors where the fully depleted body of the wafer comprises intrinsic region of the PIN structure. The novel aspect of this detector is that the one surface is divided into a two-dimensional array of pixels, and that the collected holes are divided between a row and a column collector in each pixel, yielding both dimensions of position information from this side of the detector.
Proton irradiation damage effects on current and noise in Si surface barrier transmission detectors for nuclear radiation
Electron radiation bulk damage effects on Si surface barrier detectors, determining reverse leakage current density and alpha particle response changes
There has been a continuing evolution toward larger arrays of infrared detectors, and the technology base derived from the Galileo Near Infrared Mapping Spectrometer (NIMS) has been expanded to linear arrays including from 128 to 512 elements. This advance is based on the commercial availability of high-quality InSb photodiodes and 128/256 element FET switch MUX's (multiplexing elements). The present investigation is concerned with an experimental 128-element linear imager using InSb detectors and silicon MUX for readout. Attention is given to detector array electrical characteristics, the detector readout architecture, noise, and special effects.
No abstract available
We discuss a new type of direct detector, a silicon hot-electron bolometer, for measurements in the far-infrared and submillimeter spectral ranges. High performance bolometers can be made using the electron-phonon conductance in heavily doped silicon to provide thermal isolation from the cryogenic bath. Noise performance is expected to be near thermodynamic limits, allowing background limited performance for many far infrared and submillimeter photometric and spectroscopic applications.
This document describes a high-TRL backup implementation of the anti-coincidence detector for the IXO/XMS instrument. The backup detector, hereafter referred to as the low-voltage silicon ionization detector (LVSID), has been successfully flown on Astro-E2 (Suzaku)/XRS and is currently being implemented, without significant changes, on the Astro-H/SXS instrument. The LVSID anti-coincidence detector on Astro-E2/XRS operated successfully for almost 2 years, and was not affected by the loss of liquid helium in that instrument. The LVSID continues to operate after almost 5 years on-orbit (LEO, 550 km) but with slightly increased noise following the expected depletion of solid Neon after 22 months. The noise of the device is increased after the loss of sNe due to thermally induced bias and readout noise. No radiation damage, or off-nominal affects have been observed with the LVSID on-orbit during the Astro-E2/XRS program. A detector die from the same fabrication run will be used on the Astro-H/SXS mission. The LVSID technology and cryogenic JFET readout system is thus TRL 9. The technology is described in detail in section 2. The IXO/XMS "backup-up" anti-coincidence detector is a small array of LVSID detectors that are almost identical to those employed for Astro -E2/XRS as described in this document. The readout system is identical and, infact would use the same design as the Astro -E2/XRS JFET amplifier module (19 channels) essentially without changes except for its mechanical mount. The changes required for the IXO/XMS LVSID array are limited to the mounting of the LVSID detectors, and the mechanical mounting of the JFET amplifier sub-assembly. There is no technical development needed for the IXO/XMS implementation and the technology is ready for detailed design-work leading to PDR. The TRL level is thus at least 6, and possibly higher. Characteristics of an IXO/XMS LVSID anti-co detector are given in Table 1 and described in detail in section 3.
Solid state detector - N type silicon surface barrier diode as microparticle detector
ACCESS (Assembly Concept for Construction of Erectable Space Structures) is a planned Space Station mission to measure the elemental energy spectra of Galactic cosmic rays at energies above 100 GeV/nuc. ACCESS consists of a transition radiation detector (TRD) mounted on top of an ionization calorimeter (IC). A silicon matrix detector placed on top of the IC determines the elemental identity of each cosmic ray measured by the IC. The silicon matrix must be designed to identify each cosmic ray in the presence of backscatter from the calorimeter. Because the TRD is mounted above the IC, the matrix must also recognize cosmic rays that have interacted within the TRD before reaching the IC. We will report the results of detailed GEANT simulations of the silicon matrix in ACCESS. Results will be presented on backscatter interference with charge identification and the ability of the matrix to recognize cosmic rays that interacted in the TRD.
The feasibility of detecting electrical corona discharge phenomena in a space simulation chamber via emission of ultraviolet light was evaluated. A corona simulator, with a hemispherically capped point to plane electrode geometry, was used to generate corona glows over a wide range of pressure, voltage, current, electrode gap length and electrode point radius. Several ultraviolet detectors, including a copper cathode gas discharge tube and a UV enhanced silicon photodiode detector, were evaluated in the course of the spectral intensity measurements. The performance of both silicon target vidicons and silicon intensified target vidicons was evaluated analytically using the data generated by the spectroradiometer scans and the performance data supplied by the manufacturers.
Energy for electron-hole pair generation in silicon by protons using lithium drifted semiconductor detectors
Totally depleted silicon diodes are discussed which are used as nuclear particle detectors in investigations of galactic and solar cosmic radiation and trapped radiation. A study of radiation and chemical effects on the diodes was conducted. Work on electron and proton irradiation of surface barrier detectors with thicknesses up to 1 mm was completed, and work on lithium-drifted silicon devices with thicknesses of several millimeters was begun.
Space-based gamma-ray telescopes such as the Fermi Large Area Telescope have used single sided silicon strip detectors to measure the position of incident gamma-rays with high resolution. At lower energies, two dimensional position information within a single detector is required. This talk investigates the use of monolithic CMOS active pixel silicon sensors –AstroPix – as a novel technology for use in future gamma-ray telescopes. Based upon detectors designed for use in the ATLAS detector at the LHC, AstroPix has the potential to maintain the high energy and angular resolution required of a medium-energy gamma-ray telescope while reducing noise with the dual detection and readout capabilities of a CMOS chip. The status of AstroPix development and testing, as well as outlook for application in future telescopes such as the proposed medium-energy gamma-ray telescope AMEGO-X, will be presented.
A study investigating the physical properties and use of the SiAl composite Controlled Expansion 7 (CE7) for the packaging of silicon bolometric detectors for millimeter-wave astrophysical applications at cryogenic temperatures is presented. The existing interfaces to such detectors are typically made of either ductile metals or micro-machined silicon. As a composite of Si and Al, we find that CE7 exhibits properties of both in ways that may be advantageous for this application. This exploration of the physical properties of CE7 reveals: (a) superconductivity below a critical transition temperature, T_c ∼ 1.2 K; (b) a thermal contraction profile much closer to Si than metal substrates; (c) the relatively low thermal conductivity anticipated for a superconductor, which can be improved by Au-plating; and (d) the feasibility of machining mechanical features with tolerances of ∼25 µm. We further discuss the use of CE7 in the cosmology large angular scale surveyor telescope array, which deployed CE7 in several of its detector focal planes.
A viewgraph presentation describing an ideal Silicon Carbide detector for ultraviolet, vacuum ultraviolet, extreme ultraviolet and soft x-ray detection is shown. The topics include: 1) An ideal photo-detector; 2) Dark current density of SiC photodiodes at room temperature; 3) Dark current in SiC detectors; 4) Resistive and capacitive feedback trans-impedance amplifier; 5) Avalanche gain; 6) Excess noise; 7) SNR in single photon counting mode; 8) Structure of SiC single photon counting APD and testing structure; 9) Single photon counting waveform and testing circuit; 10) Amplitude of SiC single photon counter; 11) Dark count of SiC APD photon counters; 12) Temperature-dependence of dark count rate; 13) Reduce the dark count rate by reducing the breakdown electric field; 14) Spectrum range for SiC detectors; 15) QE curves of Pt/4H-SiC photodiodes; 16) QE curve of SiC; 17) QE curves of SiC photodiode vs. penetration depth; 18) Visible rejection of SiC photodiodes; 19) Advantages of SiC photodiodes; 20) Competitors of SiC detectors; 21) Extraterrestrial solar spectra; 22) Visible-blind EUV detection; 23) Terrestrial solar spectra; and 24) Less than 1KeV soft x-ray detection.