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Nuclear Science, IEEE Transactions on

Issue 4  Part 3 • Date Aug. 2012

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  • Table of contents

    Page(s): C1 - 1479
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  • IEEE Transactions on Nuclear Science publication information

    Page(s): C2
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  • Pulse Temporal Splitting in Photon Counting X-Ray Detectors

    Page(s): 1480 - 1490
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1814 KB) |  | HTML iconHTML  

    We performed Monte-Carlo simulations of X-ray interactions and charge transport within a photon counting cadmium zinc telluride (CZT) detector. We study various physical processes affecting the width and shape of detected pulses and find that the energy resolution depends on the pulse width variance. One impact factor (and main topic of this work) is the temporal splitting of pulses due to the simultaneous creation of two or more charge clouds by K-fluorescence within the same pixel. Measured energies are underestimated if the timing constants of detector and electronics are below or in the order of the arrival time differences of the charge clouds. Pulse temporal splitting is of minor relevance if other effects like charge sharing or polarization by hole trapping are present which cause a stronger degradation of the pulse height spectrum. View full abstract»

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  • Pt-CdTe Detectors Spectroscopic Performances and RBS and XRF Interface Composition Analysis

    Page(s): 1491 - 1496
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    X- and Gamma-Ray spectroscopy measurements have been performed on differently prepared CdTe samples (as-grown or annealed, different surface treatments, etc.) with Pt electrodes deposited by electroless technique in order to extract the typical figures of merit of the material and the detectors. Moreover, Rutherford Backscattering Spectrometry (RBS) using 8 MeV ^{7}{\hbox {Li}}^{+++} ions and X-Ray Fluorescence (XRF) using a Pd-anode X-Ray generator were performed to characterize the crystal surface as well as the semiconductor-electrode interface. The thickness, the stoichiometry and the concentration profiles of platinum, cadmium and tellurium present at the surface layers were determined. The distribution of Cd deficiency at the interface layers was profiled using simulations and showed complex profiles in the samples, that can greatly affect the electrical quality of the detectors. In addition, resistivity and mu-tau product mapping and electrical measurements have been performed for material characterization. The aim of this work is to understand and improve the structure of the material-electrode interface; in particular, to understand the effect of the annealing process on the fabrication of the contacts and, at the end, on the performances of the detectors. For this reason a large number of detectors have been produced applying various chemical surface treatments on as-grown and annealed material, in order to determine the best routine way to fabricate high-quality X- and Gamma-ray detectors to be used both as large size planar detectors and as elements of imaging systems in medical or industrial applications. View full abstract»

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  • Electroless Contact Study on CdTe Nuclear Detectors: New Results and Element Deposition

    Page(s): 1497 - 1503
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    Electroless deposited contacts are frequently used for II–VI semiconductor materials and particularly on CdTe/CdZnTe. This chemical deposition method creates a stronger chemical bond and few nested interfacial layers between the contact and the semiconductor when compared to physical deposition methods such as sputtering or evaporation. This method also forms a moderate quasi-ohmic contact which eliminates the spectral degradation problem caused by the polarization effect. View full abstract»

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  • Fabrication and Characterization of {\rm Cd}_{0.9}{\rm Zn}_{0.1}{\rm Te} Schottky Diodes for High Resolution Nuclear Radiation Detectors

    Page(s): 1504 - 1509
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    Cadmium zinc telluride (CZT) Schottky diodes with very low reverse leakage current have been fabricated and characterized for high resolution gamma ray detectors. The diodes were made using {\rm Cd}_{0.9}{\rm Zn}_{0.1}{\rm Te} detector grade crystals grown from zone refined Cd, Zn, and Te (7N) precursor materials using low temperature tellurium solvent method. Various crystallographic defects including Te-inclusions/precipitates were identified and characterized using electron beam induced current (EBIC) measurement and thermally stimulated current (TSC) spectroscopy. The EBIC images were correlated with transmission infrared (TIR) images of CZT crystals and the EBIC contrast was attributed to the nonuniformities in spatial distribution of Te inclusions. Characterization by TSC revealed shallow and deep level centers with activation energies 0.25–0.4 eV and 0.65–0.8 eV respectively, which were attributed to intrinsic defects associated with Te inclusions. Pulse height measurements were carried out using ^{137}{\rm Cs} (662 keV) radiation source and energy resolution of {\sim 1.51}% full width at half maximum (FWHM) was obtained from the as-grown boule. View full abstract»

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  • New Approaches for Making Large-Volume and Uniform CdZnTe and CdMnTe Detectors

    Page(s): 1510 - 1515
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    Although CdZnTe (CZT) and CdMnTe (CMT) materials are leading contenders for room-temperature semiconductor detectors, nonetheless, both materials have limitations hindering their full usage in producing economical, uniform, large-volume devices due to their grain/twin boundaries, material purity, secondary-phase Te defects and material segregation. We tried to prevent the generation of twin and subgrain boundaries to achieve large-volume CZT crystals by means of local temperature control between the CZT melt and quartz crucible. Also, we have expanded the understanding of the electrical and structural properties of coherent/incoherent twin boundaries. The high residual impurities in the starting source materials, especially in manganese, were identified as obstacles against obtaining high-performance CMT detectors. We found that purifying manganese telluride (MnTe) via a floating Te melt-zone very effectively removes impurities, leading to better detectors. CMT detectors fabricated with purified material give a 2.1% energy resolution for 662 keV with a ^{137} Cs gamma source without any electron-loss corrections. Secondary-phase Te defects deteriorate detector performance due to incomplete charge collection caused by charge trapping. In situ growth interface studies reveal the thermo-migration of Te inclusions to CZT melts and the dependence of Te-inclusion size on the cooling rate. The effective segregation coefficient of Zn in the CdTe host is nearly 1.3, so about 5%–6% of Zn deviation was reported in Bridgman-grown CZT (Zn ,= 10% ingots. Such uncontrolled Zn variations cause a significant variation of the band-gap throughout the ingot and, consequently, affect the nonuniformity of the detectors' responses. Practically, this means that manufacturers cannot cut the ingot parallel to the crystal growth direction. We also de- onstrated that the segregation of Zn can be controlled by creating particular thermal environments after growth. View full abstract»

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  • Semi-Insulated {\rm Cd}_{1-{\rm x}}{\rm Zn}_{\rm x}{\rm Te} Grown by the Vertical Gradient Freeze Method

    Page(s): 1516 - 1521
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    One of the most fundamental parameters relating to bulk crystal growth of CZT from the melt is the temperature gradient applied at the solid-liquid interface throughout the growth cycle. {\rm Cd}_{1-{\rm x}}{\rm Zn}_{\rm x}{\rm Te} ingots grown by the vertical gradient freeze method, using dynamic temperature gradients are presented. Several complementary experimental methods have been implemented to investigate the material including mapping of resistivity, photosensitivity, infrared transmission, and measuring the low-temperature photoluminescence. Photoconductivity mapping was performed by the contactless method. Correlation of contactless resistivity and photoconductivity maps illustrate that both parameters are anticorrelated in the middle of the ingots, but correlated towards the tail end of the ingot. This observation is explained in terms of an energy shift of the Fermi level that changes the average occupation of a mid-gap level. This reasoning is further supported by photoluminescence data. View full abstract»

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  • Time-of-Flight Measurements on Schottky CdTe Detectors

    Page(s): 1522 - 1525
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    The internal electric field distribution of Schottky barrier CdTe detectors was evaluated by using time-of-flight (TOF) measurements combined with Monte Carlo (MC) simulation. The evolution of the current waveforms from less than 1 s up to about 1300 s of DC bias duration was measured at room temperature. The observed temporal behavior of the current waveforms was well reproduced by MC simulation with simple linear variation of the electric field strength distribution with position x from the anode electrode. These observations indicate accumulation of negative space charges, which screens the applied electric field progressively from the cathode side toward the bulk. Based on the evolution of the current waveforms we can successfully extract the temporal evolution of electric field distribution characterized by triple exponential function. View full abstract»

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  • Modification of the Luminescence Properties of CZT Crystals Around Tellurium Inclusions

    Page(s): 1526 - 1530
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    A 3D IR-mapping instrument has been recently developed at IMEM for the reconstruction of the position in three dimensions of Te inclusions inside CdZnTe crystals. Thanks to this apparatus, it has been possible to identify large Te inclusions ( {>}20 \mu m) located just a few micrometers below the sample surface. Photoluminescence mapping of the region close to the inclusions revealed the enhancement of a near mid-gap band emission (0.78 eV) in correspondence with the defected region surrounding the inclusion. This supports the idea that the material surrounding Te inclusions presents a high concentration of deep levels probably acting as traps or recombination centers for carriers. The present result evidences the detrimental effect of Te inclusions on charge collection efficiency. View full abstract»

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  • Unique Deep Level in Spectroscopic CdZnTe: Compensation, Trapping, and Polarization

    Page(s): 1531 - 1535
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    As yet, the role of the main native defects in the compensation, trapping, and polarization of x-ray and gamma-ray room-temperature detectors based on semi-insulated cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) is indeterminate. To better quantify it, we assessed the ionization energy, i.e., the binding energy for the hole of the second (2-/1-) acceptor level of Cd vacancies in Cd _{1 - {\rm x}} Zn _{\rm x} Te(x \approx 0.1 ). We characterized the defects in several ways, including measuring the photoconductivity at below-bandgap excitation, and photoconductivity quenching by comparing their positions in the bandgap with that of the native energy-levels in CdTe quantum dots (QDs) and other II-VI semiconductors. In this way, we determined unambiguously that a deep acceptor, Cd vacancy, behaves as a doubly charged acceptor, and the second ionization level is located at \sim {\rm E}_{\rm V}{+}(0.5 \pm 0.05) eV, i.e., relatively far from the midgap {\sim} {\hbox {0.8}} eV. This configuration may determine the lifetime of holes, but it does not stabilize precisely the compensation condition, and it is not responsible for electron trapping and polarization. View full abstract»

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  • Characterization of Edgeless CdTe Detectors for use in Hard X-Ray Imaging Applications

    Page(s): 1536 - 1543
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    Segmentation of the anode-side of a {\rm M}mathchar CdTe diode produces detectors with excellent spatial and energy resolution while maintaining an active area that extends to the detector edge. The CdTe pixel detectors reported have 250 ìm pitch, a detector thicknesses of 1 mm and are bonded to a spectroscopic readout ASIC. The results from an edgeless {\rm M}mathchar CdTe detector with indium-diffused anodes, produced via diamond blade segmentation, are compared to those of a CdTe Schottky pixel detector with aluminium anodes and guard band produced using standard photolithographic techniques. The energy resolution at 59.54 keV was measured to be 1.4% and 1.3% for the standard and edgeless detector respectively. The spectroscopic performance of pixels located at the detector edges are discussed with reference to TCAD simulations and X-ray micro-beam measurements. View full abstract»

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  • Array of Virtual Frisch-Grid CZT Detectors With Common Cathode Readout for Correcting Charge Signals and Rejection of Incomplete Charge-Collection Events

    Page(s): 1544 - 1551
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    New results from testing an array of 6 ,\times, 6 ,\times, 15 mm ^{3} virtual Frisch-grid CdZnTe (CZT) detectors with common-cathode readout for charge signals correction and rejection of incomplete charge collection events (ICC) are presented. The array employs parallelepiped-shaped crystals of a large geometrical aspect ratio with two planar contacts on the top and bottom surfaces (anode and cathode) and an additional shielding electrode placed on the sides to create the virtual Frisch-grid effect. The detectors are arranged in 2 ,\times, 2 or 3 ,\times, 3 detector modules with the common cathode readout by a single electronic channel. Because of the common cathode, the length of the shielding electrode can be further reduced with no adverse effects on the device performance. By implementing a novel technique for rejecting ICC events caused by the extended defects, we can achieve good spectral responses from ordinary CZT crystals, which can be produced with higher yield and at lower cost. For such crystals, the resolution of individual detectors is expected to be in the range of 0.8–1.5% FWHM at 662 keV with an average value of 1.3%. Arrays of virtual Frisch-grid detectors offer a robust and low-cost approach for making large-area detection modules that can potentially substitute for more advanced, but also more expensive and less available, pixel detectors in applications with slightly relaxed requirements on position- and energy-resolution (e.g., for coded aperture telescopes). In addition, such virtual Frisch-grid arrays will require a comparably smaller number of readout channels, which allows for lower power consu- ption. View full abstract»

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  • CdTe Linear Pixel X-Ray Detector With Enhanced Spectrometric Performance for High Flux X-Ray Imaging

    Page(s): 1552 - 1558
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    A growing interest has been observed in energy sensitive pixel array for high flux X-ray imaging. These devices provide compositional analysis of the imaged objects and would be useful in a wide range of applications in the field of security, non-destructive testing and medical imaging. We have developed a CdTe linear array pixel detector for energy sensitive X-ray imaging that can operate at several million counts per second. It is coupled to a novel read circuit that continuously digitizes the signal from each pixel. A FPGA is used process transient signals induced by X-rays, measuring their amplitudes and reconstruct pulse-height spectra in real time. View full abstract»

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  • Characterization of {\rm TlBr}_{\rm x}{\rm Cl}_{1mathchar Crystals for Radiation Detectors

    Page(s): 1559 - 1562
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    Thallium bromide chloride ({\rm TlBr}_{\rm x}{\rm Cl}_{1mathchar crystals have been evaluated as a material used for fabrication of room temperature radiation detectors. In this study, {\rm TlBr}_{\rm x}{\rm Cl}_{1mathchar crystals with various chlorine (Cl) concentrations were grown by the travelling molten zone method and the detectors were fabricated from the crystals. The optical properties of the crystals were evaluated by measuring the transmittances. The charge transport properties were characterized by the Hecht analysis. The band gap energy of the crystals proportionally increased with Cl concentration. Mobility-lifetime products (\mu\tau ) of the crystals decreased with increasing Cl concentration. View full abstract»

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  • X-Ray Beam Studies of Charge Sharing in Small Pixel, Spectroscopic, CdZnTe Detectors

    Page(s): 1563 - 1568
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    Recent advances in the growth of CdZnTe material have allowed the development of small pixel, spectroscopic, X-ray imaging detectors. These detectors have applications in a diverse range of fields such as medical, security and industrial sectors. As the size of the pixels decreases relative to the detector thickness, the probability that charge is shared between multiple pixels increases due to the non zero width of the charge clouds drifting through the detector. These charge sharing events will result in a degradation of the spectroscopic performance of detectors and must be considered when analyzing the detector response. In this paper charge sharing and charge loss in a 250 \mu m pitch CdZnTe pixel detector has been investigated using a mono-chromatic X-ray beam at the Diamond Light Source, U.K. Using a 20 \mu m beam diameter the detector response has been mapped for X-ray energies both above (40 keV) and below (26 keV) the material K -shell absorption energies to study charge sharing and the role of fluorescence X-rays in these events. View full abstract»

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  • Charge Transients by Variable Wavelength Optical Pulses in CdTe Nuclear Detectors

    Page(s): 1569 - 1574
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    We study charge transients induced by optical pulses in CdTe detectors. Different carrier dynamics and collection properties are observed in the signals induced by optical excitation in the wavelength range 500–1650 nm, depending on the absorption and on the transport mechanism involved. A systematic comparison between charge transients, by irradiation through cathode and anode contacts, allows to point out the role of defects near the surface, instability effects, deep level transitions into the bulk, and internal photoelectric effects at the contacts. View full abstract»

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  • Digital Spectroscopic System Based on Large Volume Stacked Coplanar Grid (Cd,Zn)Te Detectors

    Page(s): 1575 - 1581
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    The Freiburg Materials Research Center (FMF) is developing a spectroscopic system with high efficiency and high energy resolution based on (Cd,Zn)Te detectors with coplanar grid (CPG) configuration. Our system features an improved multi-channel analyzer with digital signal processing and a large volume detector stack. Thermoelectric cooling is used to improve energy resolution and maintain detector temperature at a constant value. System performance under laboratory and outdoor conditions is investigated in this paper. View full abstract»

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  • CdZnTe Focal Plane Polarimetric Performances for a Laue Lens Point Spread Function

    Page(s): 1582 - 1590
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1442 KB) |  | HTML iconHTML  

    To date in astrophysics, X- and \gamma -ray celestial emissions have been studied almost exclusively through spectral and timing variability analysis. By measuring the angle and degree of linear polarization of the detected radiation, it is possible to double the number of observational parameters, allowing better discrimination between different astrophysical models. Therefore, future \gamma -ray telescope instrumentation should include the capability to perform high sensitivity polarimetric measurements. This idea has recently become even more appealing in the perspective of new very sensitive \gamma -ray focusing missions equipped with a CdZnTe focal plane, such as the Gamma-Ray Imager and DUAL missions submitted to the European Space Agency's Cosmic Vision calls. By combining the most recent simulation developments and the latest experimental results we present the best polarization assessment so far of such a CdZnTe focal plane when coupled to wide band-pass Laue optics (up to 1 MeV). Firstly, the Laue lens response to different source types (Crab type and monochromatic) was simulated by a Monte Carlo code generating a characteristic PSF (point spread function). Afterwards this PSF served as the input to the focal plane mass model simulation. We have calculated the respective modulation Q factor for on- and off-axis (2') sources. Finally, experimental polarimetric performances of a CdZnTe prototype operating together with Laue lens crystal samples, tested at the European Synchrotron Radiation Facility, validated the focal plane simulation results ( Q\sim 0.30 to 0.40, 200 keV to 600 keV range). A minimum detectable polarization- of 2% (3\sigma ,10^{6}~{\rm s}) was estimated for a 100 mCrab, type source, which is compatible with the high polarimetric sensitivity required for space \gamma -ray polarimetry. View full abstract»

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  • Characterization of 4H-SiC Epitaxial Layers and High-Resistivity Bulk Crystals for Radiation Detectors

    Page(s): 1591 - 1596
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    Defect and electrical characterization of bulk semi-insulating (SI) 4H-SiC crystals and SI and n-type 4H-SiC epitaxial layers grown by chemical vapor deposition (CVD) on highly doped (0001) 4H-SiC substrates is reported. Optical microscopy, electron beam induced current (EBIC) imaging, current-voltage ( I V ) measurements, thermally stimulated current (TSC) spectroscopy (94 K–620 K), Hall effect, and van der Pauw measurements have been conducted for characterization and defect correlation studies. Both epitaxial layers exhibited relatively shallow levels related to Al, B, L - and D-centers. Deep level centers in the n-type epitaxial layer peaked at {\sim} 400 K ( E_{a} \sim 1.1 eV), and {\sim} 470 K were correlated with IL_{2} defect and 1.1 eV center in high-purity bulk SI 4H-SiC. The SI epitaxial layer exhibited peak at {\sim} 290 K ( E_{a} = 0.82\hbox {--}0.87 eV) that was attributed to IL_{1} and HK2 centers, and at {\sim} 525 K that was related to intrinsic defects and their complexes with energy levels close to the middle of the band-gap. Results of EBIC and optical microscopy showed segregation of threading dislocations around comet tail defects in the n-type epitaxial layer. The V characteristics of the devices on SI epitaxial layer exhibited steps corresponding to the ultimate trap filling of deep centers. The high-temperature resistivity measurements of bulk SI 4H-SiC sample revealed resistivity hysteresis that was attributed to the filling of the deep-level electron trap centers. The responsivity of the n-type epitaxial 4H-SiC detector in the soft X-ray energy range is reported for the first time. View full abstract»

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  • First Operational Experience With a High-Energy Physics Run Control System Based on Web Technologies

    Page(s): 1597 - 1604
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (737 KB) |  | HTML iconHTML  

    Run control systems of modern high-energy particle physics experiments have requirements similar to those of today's Internet applications. The Compact Muon Solenoid (CMS) collaboration at CERN's Large Hadron Collider (LHC) therefore decided to build the run control system for its detector based on web technologies. The system is composed of Java Web Applications distributed over a set of Apache Tomcat servlet containers that connect to a database back-end. Users interact with the system through a web browser. The present paper reports on the successful scaling of the system from a small test setup to the production data acquisition system that comprises around 10.000 applications running on a cluster of about 1600 hosts. We report on operational aspects during the first phase of operation with colliding beams including performance, stability, integration with the CMS Detector Control System and tools to guide the operator. View full abstract»

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  • On-Chip Real-Time Correction for a 20-ps Wave Union Time-To-Digital Converter (TDC) in a Field-Programmable Gate Array (FPGA)

    Page(s): 1605 - 1610
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    The latest delay chain-based FPGA TDCs can achieve resolutions around 10 ps. At such high levels of accuracy, delay chains become very sensitive to parasitic electromagnetic perturbations, including power supply voltage, temperature, and current surge. This paper describes how common-mode fast perturbation can deteriorate the spectra and make the root mean square (RMS) periodical as the input time interval increases. Based on this observation, an on-chip real-time correction method can be implemented, giving a correcting reference for each sample. Results show a typical RMS of 20 ps, with a maximum value below 30 ps, under the perturbation of around 100 mV and 20 kHz coming from the DC-DC module. View full abstract»

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  • Front end Electronics for SLHC Semiconductor Trackers in CMOS 90 nm and 130 nm Processes

    Page(s): 1611 - 1620
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    We present the development of a front end amplifier and discriminator circuit implemented in two successive nodes of commercial CMOS process, namely 90 nm and 130 nm. The aim of this work is two-fold, firstly to examine new technology features such as increased transconductance and transit frequency f_{t} resulting in higher speed at lower power consumption, and secondly to prototype a novel front end architecture developed to maintain high dynamic range and open loop gain in the presence of the degradation of intrinsic transistor gain and low supply voltage accompanying the scaling of CMOS processes. The circuits are intended to work with silicon strip detectors of moderate length. Although both versions are optimized for 5 pF input capacitance, the input stage of 130 nm front end can be biased with a current allowing for readout of detectors with capacitances of the order of 10 pF. Special attention has been given to the comparison of noise performance and matching of the channel gain and discriminator offsets. Although both versions show good basic analog performance in terms of speed and gain, an appreciable difference in the channel-to-channel matching and the noise figures is measured. The ENC performance of 130 nm version of the amplifier follows theoretical predictions confirming no excess noise for the devices used, whilst the noise performance of the 90 nm version is noticeably worse. Looking at the difference in noise performance between the two designs, the 130 nm process is better understood and is thus a more appropriate choice for the current upgrade project. As a consequence, the presented 130 nm design will form the core of the ABC130 chip for the ATLAS SCT upgrade. View full abstract»

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  • Accurate Analytical Model for Single Event (SE) Crosstalk

    Page(s): 1621 - 1627
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    With advances in modern technology, circuits become more sensitive to single event transient (SET) due to decreased device feature size and increased coupling effects among interconnects, which might cause SET to affect multiple logic paths. This paper proposed an accurate and efficient SE crosstalk estimation model based on point admittance and equivalent circuit of SET. The proposed model uses a 6-node template circuit of interconnect and simplifies the calculation by use of point admittance. By use of Taylor series expansion theorem, the analytical expressions of noise peak voltage and pulse width are obtained. The waveform of SE crosstalk in the analytical model is very good in agreement with SPICE. Results from 1000 random cases show that by comparison with previous works, the model has a significant improved accuracy with an average error of only 3.07% in noise peak voltage, and 8.11% in pulse width, respectively. These results validate that the analytical model is efficient and accurate. View full abstract»

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  • Polarization Degree and Direction Angle Effects on a CdZnTe Focal Plane Performance

    Page(s): 1628 - 1635
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (979 KB) |  | HTML iconHTML  

    To date in astrophysics, X- and gamma-ray source emissions have been studied almost exclusively through imaging techniques, spectral- and timing-variability analysis. However, often two or more distinct models potentially describe the same observations of a particular celestial-radiation source. By measuring the angle and degree of linear polarization of the detected radiation, it is increased by two the number of observational parameters thereby allowing a better discrimination between different models. Therefore, future \gamma -ray-telescope instrumentation should include the capability to perform highly sensitive polarimetric measurements. This idea has recently become even more important from the perspective of new very sensitive hard X- and soft gamma-ray focusing missions based on Laue lenses such as the Gamma-Ray Imager and DUAL missions, submitted to ESA Cosmic Vision calls. In order to optimize the design of a gamma-ray telescope focal plane, a CdZnTe detector prototype has been tested at the European Synchrotron Radiation Facility under a {\sim}100\hbox {%} polarized gamma-ray beam. The tested detector was a 5 mm thick CdZnTe array with segmented anodes into 16 ,\times, 16 pixels of 2.5 ,\times, 2.5 mm ^{2} . The aim of these tests was to study the polarimetric performance of this prototype as a function of the polarization state of the synchrotron beam. In particular, we determined the sensitivity of the detector to the level of the beam polarization as well as its potential to determine the polarization angle orientation by performing measurements at different polarization direction angles. In both tests the CdZnTe pro- otype showed a good linearity in its response and good sensitivity to polarization levels down to 50% and a polarization angular resolution better than 5 ^{\circ} . View full abstract»

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IEEE Transactions on Nuclear Science focuses on all aspects of the theory and applications of nuclear science and engineering, including instrumentation for the detection and measurement of ionizing radiation; particle accelerators and their controls; nuclear medicine and its application; effects of radiation on materials, components, and systems; reactor instrumentation and controls; and measurement of radiation in space.

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