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Silicon detector

R O'Connell, Y Chen, H Zhang, Y Zhou, D Fox, P Maguire, J J Wang, C Rodenburg
Images of Ga(+) -implanted amorphous silicon layers in a 110 n-type silicon substrate have been collected by a range of detectors in a scanning electron microscope and a helium ion microscope. The effects of the implantation dose and imaging parameters (beam energy, dwell time, etc.) on the image contrast were investigated. We demonstrate a similar relationship for both the helium ion microscope Everhart-Thornley and scanning electron microscope Inlens detectors between the contrast of the images and the Ga(+) density and imaging parameters...
December 2017: Journal of Microscopy
Kyle A Beyer, Angela Di Fulvio, Liliana Stolarczyk, Wiktor Parol, Natalia Mojzeszek, Renata Kopéc, Shaun D Clarke, Sara A Pozzi
We developed a radiation detector based on an organic scintillator for spectrometry and dosimetry of out-of-field secondary neutrons from clinical proton beams. The detector consists of an EJ-299-34 crystalline organic scintillator, coupled by fiber optic cable to a silicon photomultiplier (SiPM). Proof of concept measurements were taken with 137Cs and 252Cf, and corresponding simulations were performed in MCNPX-PoliMi. Despite its small size, the detector is able to discriminate between neutron and gamma-rays via pulse shape discrimination...
November 15, 2017: Radiation Protection Dosimetry
Mostafa Shalaby, Carlo Vicario, Christoph P Hauri
Charge-coupled devices (CCDs) are a well-established imaging technology in the visible and x-ray frequency ranges. However, the small quantum photon energies of terahertz radiation have hindered the use of this mature semiconductor technological platform in this frequency range, leaving terahertz imaging totally dependent on low-resolution bolometer technologies. Recently, it has been shown that silicon CCDs can detect terahertz photons at a high field, but the detection sensitivity is limited. Here we show that silicon, complementary metal-oxide-semiconductor (CMOS) technology offers enhanced detection sensitivity of almost two orders of magnitude, compared to CCDs...
November 15, 2017: Optics Letters
Ming Ren, Jierui Zhou, Bo Song, Chongxing Zhang, Ming Dong, Ricardo Albarracín
Optical detection is reliable in intrinsically characterizing partial discharges (PDs). Because of the great volume and high-level power supply of the optical devices that can satisfy the requirements in photosensitivity, optical PD detection can merely be used in laboratory studies. To promote the practical application of the optical approach in an actual power apparatus, a silicon photomultiplier (SiPM)-based PD sensor is introduced in this paper, and its basic properties, which include the sensitivity, pulse resolution, correlation with PD severity, and electromagnetic (EM) interference immunity, are experimentally evaluated...
November 10, 2017: Sensors
Stephen W Howell, Isaac Ruiz, Paul S Davids, Richard K Harrison, Sean W Smith, Michael D Goldflam, Jeffrey B Martin, Nicholas J Martinez, Thomas E Beechem
A sensitive optical detector is presented based on a deeply depleted graphene-insulator-semiconducting (D(2)GIS) junction, which offers the possibility of simultaneously leveraging the advantages of both charge integration and localized amplification. Direct read-out and built-in amplification are accomplished via photogating of a graphene field-effect transistor (GFET) by carriers generated within a deeply depleted low-doped silicon substrate. Analogous to a depleted metal-oxide-semiconducting junction, photo-generated charge collects in the potential well that forms at the semiconductor/insulator interface and induces charges of opposite polarity within the graphene film modifying its conductivity...
November 7, 2017: Scientific Reports
Rongxiao Zhang, Kyung-Wook Jee, Ethan W Cascio, Gregory C Sharp, Jacob B Flanz, Hsiao-Ming Lu
Proton radiography, which images patients with the same type of particles as what they are to be treated with, is a promising approach to image guidance and water equivalent path length (WEPL) verification in proton radiation therapy. We have shown recently that proton radiographs could be obtained by measuring time-resolved dose rate functions (DRF) using an x-ray amorphous silicon flat panel. The WEPL values were derived solely from the root-mean-square (RMS) of DRFs while the intensity information in the DRFs was filtered out...
November 8, 2017: Physics in Medicine and Biology
Ryusuke Nakamoto, Yuji Nakamoto, Takayoshi Ishimori, Yasutaka Fushimi, Aki Kido, Kaori Togashi
Objectives: The current study tested a newly developed flexible PET (positron emission tomography) scanner prototype. This flexible PET (fxPET) system involves dual arc-shaped detectors based on silicon photomultipliers, which are designed to fit existing magnetic resonance (MR) devices, allowing us to get fused PET and MR images by sequential PET scanning. This prospective study sought to evaluate image quality, lesion detection rate, and quantitative values of fxPET in comparison with conventional whole-body (WB) PET images, and to assess the accuracy of registration...
November 2, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
T Friedrich, A Bochmann, J Dinger, S Teichert
In this paper an alternative method of off-line Kikuchi pattern centre calibration and orientation mapping, utilising the cross-correlation between entire experimental patterns and dynamical simulated patterns is applied and evaluated. To demonstrate the improvement in angular resolution compared to Hough transform based methods, EBSD datasets of a silicon monocrystal were analysed using both, classical and the presented cross-correlation based method, which revealed significant enhancement of angular resolution for the refined method...
October 12, 2017: Ultramicroscopy
John F Seely, Lawrence T Hudson, Albert Henins, Uri Feldman
An x-ray spectrometer employing a thin (50 μm) silicon transmission crystal was used to record high-resolution Cu Kα spectra from a laboratory x-ray source. The diffraction was from the (331) planes that were at an angle of 13.26° to the crystal surface. The components of the spectral lines resulting from single-vacancy (1s) and double-vacancy (1s and 3d) transitions were observed. After accounting for the natural lifetime widths from reference double-crystal spectra and the spatial resolution of the image plate detector, the intrinsic broadening of the transmission crystal was measured to be as small as 0...
October 2017: Review of Scientific Instruments
Ivan Prochazka, Jan Kodet, Johann Eckl, Josef Blazej
We are reporting on the design, construction, and performance of a photon counting detector system, which is based on single photon avalanche diode detector technology. This photon counting device has been optimized for very high timing resolution and stability of its detection delay. The foreseen application of this detector is laser ranging of space objects, laser time transfer ground to space and fundamental metrology. The single photon avalanche diode structure, manufactured on silicon using K14 technology, is used as a sensor...
October 2017: Review of Scientific Instruments
Allison Toltz, Michaela Hoesl, Jan Schuemann, Jan Seuntjens, Hsiao-Ming Lu, Harald Paganetti
PURPOSE: Our group previously introduced an in vivo proton range verification methodology in which a silicon diode array system is used to correlate the dose rate profile per range modulation wheel cycle of the detector signal to the water-equivalent path length (WEPL) for passively scattered proton beam delivery. The implementation of this system requires a set of calibration data to establish a beam-specific response to WEPL fit for the selected 'scout' beam (a 1 cm overshoot of the predicted detector depth with a dose of 4 cGy) in water-equivalent plastic...
October 29, 2017: Journal of Applied Clinical Medical Physics
Christian Finck, Yusuf Karakaya, Valérian Reithinger, Regina Rescigno, Jérôme Baudot, Julie Constanzo, Didier Juliani, Jochen Krimmer, Ilaria Rinaldi, Marc Rousseau, Etienne Testa, Marie Vanstalle, Cedric Ray
Ion beam therapy enables a highly accurate dose conformation delivery to the tumor due to the finite range of charged ions in matter (i.e., Bragg Peak (BP)). Consequently, the dose profile is very sensitive to patients anatomical changes as well as minor mispositioning, and so it requires improved dose control techniques. Proton Interaction Vertex Imaging (IVI) could offer an online range control in carbon ion therapy. In this paper, a statistical method was used to study the sensitivity of the IVI technique on experimental data obtained from the Heidelberg Ion-Beam Therapy Center...
October 23, 2017: Physics in Medicine and Biology
Hartmut Sadrozinski, Abraham Seiden, Nicolo Cartiglia
The evolution of particle detectors has always pushed the technological limit in order to provide enabling technologies to researchers in all fields of science. One archetypal example is the evolution of silicon detectors, from a system with a few channels 30 years ago, to the tens of millions of independent pixels currently used to track charged particles in all major particle physics experiments. Nowadays, silicon detectors are ubiquitous not only in research laboratories but in almost every high tech apparatus, from portable phones to hospitals...
October 20, 2017: Reports on Progress in Physics
C D Munson, S K Choi, K P Coughlin, J J McMahon, K H Miller, L A Page, E J Wollack
Infrared (IR)-blocking filters are crucial for controlling the radiative loading on cryogenic systems and for optimizing the sensitivity of bolometric detectors in the far-IR. We present a new IR filter approach based on a combination of patterned frequency-selective structures on silicon and a thin (25-75 μm thick) absorptive composite based on powdered reststrahlen absorbing materials. For a 300 K blackbody, this combination reflects ∼50% of the incoming light and blocks >99.8% of the total power with negligible thermal gradients and excellent low-frequency transmission...
July 1, 2017: Applied Optics
Linyue Liu, Ao Liu, Song Bai, Ling Lv, Peng Jin, Xiaoping Ouyang
Silicon carbide (SiC) is a wide band-gap semiconductor material with many excellent properties, showing great potential in fusion neutron detection. The radiation resistance of 4H-SiC Schottky diode detectors was studied experimentally by carefully analyzing the detectors' properties before and after deuterium-tritium fusion neutron irradiation with the total fluence of 1.31 × 10(14) n/cm(2) and 7.29 × 10(14) n/cm(2) at room temperature. Significant degradation has been observed after neutron irradiation: reverse current increased greatly, over three to thirty fold; Schottky junction was broken down; significant lattice damage was observed at low temperature photoluminescence measurements; the peaks of alpha particle response spectra shifted to lower channels and became wider; the charge collection efficiency (CCE) decreased by about 7...
October 17, 2017: Scientific Reports
Tianqi Zhao, Yu Peng, Quanlong Miao, Baicheng Li, Kun Liang, Ru Yang, Dejun Han
We present a one-dimensional (1-D) single-photon position-sensitive silicon photomultiplier (PS-SiPM) that can perform both photon number and position discriminations. The device, which features epitaxial quenching resistors and a continuous cap resistive layer for charge division, possesses two cathodes on top and one anode at the bottom. The PS-SiPM shows an active size of 2.2 mm × 2.2 mm and micro avalanche photodiode cell pitch of ~10 μm. The position measurement error (PME) and position resolution of the device are analyzed...
September 18, 2017: Optics Express
Zhao Wang, Dixon Paez, Ahmed I Abd El-Rahman, Peng Wang, Liam Dow, John C Cartledge, Andrew P Knights
A method to stabilize the resonance wavelength of a depletion-type silicon micro-ring resonator modulator during high-speed operation is described. The method utilizes the intrinsic defect-mediated photo-absorption of a silicon waveguide and results in a modulator chip fabrication process that is free of heterogeneous integration (for example using germanium), thus significantly reducing the complexity and cost of manufacture. Residual defects, present after p-n junction formation, are found to produce an adequate photocurrent for use as a feedback signal, while an integrated heater is used to compensate for thermal drift via closed-loop control...
October 2, 2017: Optics Express
P Szypryt, S R Meeker, G Coiffard, N Fruitwala, B Bumble, G Ulbricht, A B Walter, M Daal, C Bockstiegel, G Collura, N Zobrist, I Lipartito, B A Mazin
We have fabricated and characterized 10,000 and 20,440 pixel Microwave Kinetic Inductance Detector (MKID) arrays for the Dark-speckle Near-IR Energy-resolved Superconducting Spectrophotometer (DARKNESS) and the MKID Exoplanet Camera (MEC). These instruments are designed to sit behind adaptive optics systems with the goal of directly imaging exoplanets in a 800-1400 nm band. Previous large optical and near-IR MKID arrays were fabricated using substoichiometric titanium nitride (TiN) on a silicon substrate. These arrays, however, suffered from severe non-uniformities in the TiN critical temperature, causing resonances to shift away from their designed values and lowering usable detector yield...
October 16, 2017: Optics Express
Stephen Manu, Patcharapong Suntharos, Gerard J Boyle, Lu Wang, Lourdes R Prieto
OBJECTIVES: Radiation dose was compared between two modern imaging systems with different x-ray tube technology (Megalix vs Gigalix) and detector type (amorphous vs crystalline silicon) at the same institution. BACKGROUND: Further reduction in radiation dose than currently reported may be achievable with advances in x-ray tube and detector technology. METHODS: Radiation dose (air kerma, dose-area product [DAP]) was retrospectively compared for post-transplant pediatric patients undergoing right heart catheterization/biopsy (fluoroscopy only) or "annual" catheterization with coronary angiography in one of two imaging systems between January 2014 and December 2016...
October 15, 2017: Journal of Invasive Cardiology
Moritz Budde, Irenäus A Adamietz, Holger Sommer, Horst Hermani
The surgical removal of a breast tumour is often followed by postoperative irradiation of the surrounding tissue with a radioactive source (brachytherapy). When performing the MammoSite procedure, a spherical silicone balloon is inserted and filled with a NaCl solution. In a period of about five days in several sessions an iridium-192 source with high activity travels through a catheter into the balloon (afterloading) to irradiate the tumour cells remaining in the cavity. In this study, dose distributions of a MammoSite applicator are investigated based on measurements with a 2D detector array, Monte Carlo simulations and calculations with BrachyVision...
October 12, 2017: Zeitschrift Für Medizinische Physik
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