Si PIN Diodes Research Articles

Total kinetic energy release in the fast neutron induced fission of actinide nuclei

The total kinetic energy release and fission mass distributions for the fast neutron (En = 3–100 MeV) induced fission of 232Th, 233U, 235U, 237Np, 239Pu, 240Pu, and 242Pu have been measured using the LANSCE facility. The neutron energies were deduced from time-of- flight measurements. The fission fragments were detected using Si PIN diode detectors, giving us the fragment energies. The actinide targets were made by vapor deposition leading to high-quality targets, that were thin and uniform with reduced impurities. Corrections were made to the data for pulse height defect and the fragment energy loss in the target and its backing. The TKE distributions were Gaussian in shape and their mean value as a function of incoming neutron energy could be fitted with second order polynomials. In the case of 233U and 235U, our measurements agree with prior work. Our measurements for 232Th are unique. Our data agree with Viola scaling. The constant position of the heavy mass peak is interpreted as being due to the influence of the N = 88 and Z = 50 shells. The GEF model predictions agree with the data in general as do the CGMF model predictions.

Effect of reverse voltage on alpha spectra of pre-conditioned Si PIN diodes deployed in vacuum/ambient environment

Semiconductor-based Si PIN diodes are employed for radiation detection owing to their many advantages. However, their performance and reliability heavily rely on their pre-conditioning and the environment in which they are deployed. In this article, the response of Si PIN diodes that are subjected to two different pre-conditions [heat-treated at 100 °C (HT) and exposed to 85% relative humidity (HUM)] and two deployment environments [vacuum and ambient] to alpha particles emanating from triple-alpha source (239Pu-5155 keV, 241Am-5486 keV, and 244Cm-5805 keV) are investigated. Prior to alpha spectroscopy measurements, a meticulous electrical characterization, in terms of reverse current-voltage (IR-VR) and reverse capacitance-voltage (CR-VR) measurements are carried out. The IR-VR characteristics revealed that the leakage current (IR) is higher for measurements performed in ambient as compared to vacuum, while CR-VR characteristics are utilized to set the minimum reverse voltage (VR) that resulted in depletion width commensurate with the range of alpha particles. In order to confirm the optimum VR for maximum charge collection, alpha spectra are obtained in vacuum conditions for different values of VR ranging from 0 to 48.6 V, which showed a left-exponential Gaussian convoluted lineshape. A systematic analysis of the lineshape in terms of the fitting parameters viz, peak position, FWHM, area under the peak, and tailing parameter, revealed that the most robust data is obtained at an optimum VR of 4.6 V, where saturation is observed in peak position, area under the peak and tailing parameter. It is to be added that in the present experiment, 4.6 V is the optimum VR for obtaining robust measurements even for pre-conditioned diodes in different deployment conditions and is thus suitable for field condition measurements.

Effect of pre-adsorbed moisture and humidity on I–V characteristics of Si PIN diode

Effect of pre-adsorbed moisture and humidity on I–V characteristics of Si PIN diode

An active transverse energy filter to differentiate low energy particles with large pitch angles in a strong magnetic field

We present the idea and proof of principle measurements for an angular-selective active filter for charged particles. The motivation for the setup arises from the need to distinguish background electrons from signal electrons in a spectrometer of MAC-E filter type. While a large fraction of the background electrons exhibit predominantly small angles relative to the magnetic guiding field (corresponding to a low amount of kinetic energy in the motion component transverse to the field lines, in the following referred to as transverse energy) and pass the filter mostly unhindered, signal electrons from an isotropically emitting source interact with the active filter and are detected. The concept is demonstrated using a microchannel plate (MCP) as an active filter element. When correctly aligned with the magnetic field, electrons with a small transverse energy pass the channels of the MCP without interaction while electrons with large transverse energies hit the channel walls and trigger an avalanche of secondary electrons that is subsequently detected. Due to several drawbacks of MCPs for an actual transverse energy filter, an alternative detection technique using microstructured Si-PIN diodes is proposed.

Building a VME spectrometer and testing Si PIN diode detector: a feasibility study for the first nuclear astrophysical experiments using a pelletron

This work presents the logical design, connections between NIM and VME elec­tronic modules, and the data acquisition programming to build a complete detector readout system. The test experiments were carried out with commercial silicon PIN diode S3590-09 bare detectors bombarded by charged particles from a 241Am α-source and Rutherford elastic backscattering (RBS) protons induced by 2.5 MeV proton beam bombarding on an Au-on-glass target, and with a NaI scintillation detector bombarded by gammas from 27Al(p, γ)28Si reaction with proton beam energy of 1.379 MeV. The test showed that the spectrometer operated steadily and its versatility for different kind of detector. The energy resolutions of the Si diodes were less than 0.5% energy of a charged particle, which satisfies the foreseen requirement for the upcoming experiments.

Optimizations of Si PIN diode phase-shifter for controlling MZM quadrature bias point using SOI rib waveguide technology

Commercial high-speed silicon (Si) Mach-Zehnder modulator (MZM) required to be active around the quadrature bias point (linear transmission area) with low power consumption, small footprint, and small drive voltage. The bias controlling is done by an optical phase-shifter (PS). However, the accuracy is limited by the drive voltage, laser thermal drift, and fabrication errors. To overcome these problems, we propose in this paper the study and analysis of Si PIN diode PS under forward biasing at 1550 nm wavelength using the standard 220 nm substrate silicon-on-insulator (SOI) rib waveguide technology. Numerical investigations were carried out on the key geometrical parameters, doping concentration, doping locations, operating wavelength, biasing level. Results show that the optimal design can be operated with a lower voltage (Vπ = 1.629 v), lower attenuation (α = 28.985 dB/cm), and short device length with an extremely small voltage-length product VπL = 0.815 vmm. Thus, this PS can be used for designing an efficiency high-speed MZM and to obtain better performances in the optical commutation system.

Comparative Numerical Analysis of the Robustness of Si and SiC PiN Diodes Against Cosmic Radiation-Induced Failure

This work aims at extending the predictive simulation technique for cosmic ray-induced failure analysis from Si PiN diodes [1] to SiC PiN diodes. Accurate 3D cylindrical-symmetric transient simulations were performed with a minimum mesh size of 20nm at the center track of the impinging ion and a maximum time step of 0.1ps during the development of the ion-induced transient current. We made a comparative study between a SiC PiN diode and a Si PiN diode with the same blocking voltage of 1.5kV, using the same heavy ion transportation models. In the simulation, we observed different ion-induced current transients, differing not only in the peak value of the current, but also in its duration. Due to different physical mechanisms, the dependence of the ion-induced current on the reverse pre-bias voltage and the numerical mesh adaptations are also different. Eventually, we brieflydiscuss electro-thermal simulations, which indicate once more that the ion-induced transient current in the SiC PiN diodes under consideration is primarily drift current and involves only negligible impact ionization.

Investigation of thermal treatment on improving the performance behavior of Si PIN alpha radiation detectors

The silicon-based PIN-type photodiode was designed and fabricated employing conventional bipolar planar technology using different annealing process to reduce the leakage current and detector energy resolution. In this process the effects of the Annealing and gas flow rate on the detector electrical properties such as capacitance-voltage (C–V) of MOS capacitors and current-voltage (I–V) of diodes and alpha spectral measurement are specified. Silicon PIN radiation detectors are made on four similar fabrication process with different post thermal annealing at constant temperature and different hydrogen gas flow (10 sccm–60 sccm). The study results proves that the detector with 15 sccm hydrogen gas flow shows lower leakage current due to the lower remained interface traps density at the Si/SiO2 interface. Si PIN diodes were fabricated, by considering all the important aspects discussed in this paper, and consequently an excellent spectral response was observed.

Current–voltage characteristics of silicon PIN diodes irradiated in KAMINI nuclear reactor

The present study reports on the investigation of current–voltage (I–V) characteristics of commercial planar Si-PIN diodes, irradiated in a typical thermal nuclear reactor — KAMINI for neutron fluences ranging from 1×1014 to 1×1016 n/cm2. The I–V Characteristics of the virgin and neutron irradiated Si-PIN diodes are measured in ambient environment for the forward and reverse biased conditions. In the forward bias condition, one of the consequences of increasing the neutron irradiation fluence is the increase in knee voltage from ∼0.5 V for virgin diode to 37.4 V for neutron irradiated diode with fluence of 1×1016 n/cm2. Further analysis of forward characteristics, revealed increase in ideality factor from a typical value of ∼2 for virgin diode to an anomalous value of ∼496 for the highest irradiated diode specimen. This increase is attributed to the increasing neutron damage that the diodes undergo upon irradiation. Moreover, in the reverse biased condition, the reverse leakage current increased by four orders of magnitude from 10−9 to 10−5 ampere. A qualitative analysis of the forward and reverse I–V characteristics, showed that the diodes change from a rectifying to ohmic behaviour with increase in neutron fluence and this was inferred from the decrease in ‘gap’ between the forward and reverse currents in the low voltage regions. Quantitatively, the rectification ratio – ratio of the forward to reverse currents – was calculated to be 108 and 84 for the virgin and 1 × 1016 n/cm2 irradiated specimens, respectively. The damage constant evaluated from the reverse bias I–V measurements conditions was found to be 1.7683 × 10−18 A/cm.

Histria – Acropolă Centru-Sud. Date asupra artefactelor din materii dure animale (I) / Histria – Acropolis Centre-South. Data on bone and antler artefacts (I)

The analysis of the artefacts from osseous raw materials discoveret in Histria – Acropolis Centre‐ South Sector is integrated in the series of extensive scientific valorisation of the artefacts from osseous raw materials recovered from archaeological sites located in Dobrudja – see the bibliography. Consequently, the common and significant presence of this kind of artefacts is documented in terms of quantities, types and data obtained from the inventory of the archaeological structures dated to the Roman and Roman‐ Byzantine periods in Histria – Acropolis Centre‐ South Sector. Their systematic recovery and study will continue to be a goal for the research team of this sector as part of the broader scientific objectives of the on‐ going project. The article offers the extensive primary research data of the assemblage obtained following the 2013– 2016 archaeological campaigns, comprising 31 pieces. The typological categories are quite various : tools, adornments, accessories, hafts, raw materials and debris. The local procurement of osseous raw materials (bone, deer antler, wild boar tusks) is taken into account. The artefacts have been made probably within mixt workshops (metal, wood, bone etc.), where various tools, accessories from different raw materials etc. have been produced. The technical solutions of manufacture have been defined using microscopic analysis. Artefacts are dated in the Roman and Roman‐ Byzantine periods (2nd– 6th century AD). Further chronological data cannot be formulated due to the disturbed context of last dwelling levels and standardised parameters of the artefacts. The piece HIS‐ ACS_ 15 (dated to the 6th century AD, Fig. 16) is a remarkable exception due to its ornamentation, which attests the use of dye that was exceptionally well preserved. Given the fact that the decoration of the bone item still preserves traces of black pigment, the team decided to conduct a compositional non‐ destructive analysis using a portable X‐ Ray Fluorescence spectrometer Innov‐ X Systems Alpha Series, with W anticathode tube, SiPIN diode, Peltier cooling effect. The analysis on Analytical mode was conducted on both the interior side (less finished, undecorated) and the exterior side (finely worked, decorated) in order to determine possible differences in the composition (Tables 6– 7, Graph 5). The analysis conducted on the upper (decorated) side indicates again the presence of iron and lead, but this time the latter in a very high amount (70.51% Pb). The presence of both lead and iron on the surface of the decorated object could be possibly explained in terms of the original use of two pigments of different origin, one based on iron (an iron oxide – ochre ?) and another on lead. These would have been either mixed to obtain a final desired colour or combined to obtain two different hues or nuances on the surface (for example, ground in one hue of red and the concentric circles in another). Another possible explanation is that the surface of the object was coloured in black using only a lead oxide, while the presence of iron indicates the prolonged contact of the bone object with an iron object. The fact that the amount of iron is much higher on the interior of the object, in combination with the presence of zinc and a small amount of lead, could serve as an argument in favour of the original use of the red deer item as a convex plaque for an iron object. Artefacts made of osseous raw materials which were studied on this occasion offer important typological and technological benchmarks for complex and extensive approach of civilisation and culture of the Histrian communities during Roman and Roman‐ Byzantine epoch.

The differential absorption hard x-ray spectrometer at the Z facility

The differential absorption hard X-ray (DAHX) spectrometer is a diagnostic developed to measure time-resolved radiation between 60 keV and 2 MeV at the Z Facility. It consists of an array of seven Si PIN diodes in a tungsten housing that provides collimation and coarse spectral resolution through differential filters. DAHX is a revitalization of the hard X-ray spectrometer that was fielded on Z prior to refurbishment in 2006. DAHX has been tailored to the present radiation environment in Z to provide information on the power, spectral shape, and time profile of the hard emission by plasma radiation sources driven by the Z machine.

Demonstration of 13-kV Class Junction Barrier Schottky Diodes in 4H-SiC with Three-Zone Junction Termination Extension

The static and dynamic characteristics of 13-kV class 4H-SiC junction barrier Schottky (JBS) diodes with a three-zone junction termination extension (JTE) are presented. Using an anisotropy breakdown model, technology computer-aided design simulation of devices with a three-zone JTE agrees well with the obtained experimental results, correctly predicting a sharp drop in blocking voltage at high JTE acceptor concentrations. The forward voltage of the JBS diode at 75°C and a forward current of 500 mA is reduced to approximately one-ninth by that of 13 series-connected 1000-V Si PiN diodes. This suggests that conduction losses of traditional high-voltage circuits which conventionally use series-connected devices can be drastically reduced by replacing the series-connected devices with a single 13-kV class SiC JBS diode. Moreover, the reverse recovery current waveform of the 13-kV class SiC JBS diode shows that these diodes have lower reverse recovery losses than a 13-kV SiC PiN diode.

Note: Coincidence measurements of 3He and neutrons from a compact D-D neutron generator.

Tagging of neutrons (2.45 MeV) with their associated 3He particles from deuterium-deuterium (D-D) fusion reactions has been demonstrated in a compact neutron generator setup enabled by a high brightness, microwave-driven ion source with a high fraction of deuterons. Energy spectra with well separated peaks of the D-D fusion reaction products, 3He, tritons, and protons, were measured with a silicon PIN diode. The neutrons were detected using a liquid scintillator detector with pulse shape discrimination. By correlating the 3He detection events with the neutron detection in time, we demonstrated the tagging of emitted neutrons with 3He particles detected with a Si PIN diode detector mounted inside the neutron generator vacuum vessel.

Baseline restoration technique based on symmetrical zero-area trapezoidal pulse shaper

Since the baseline of the unipolar pulse shaper have the direct-current (DC) offset and drift, an additional baseline estimator is need to obtain baseline values in real-time. The bipolar zero-area (BZA) pulse shapers can be used for baseline restoration, but they cannot restrain the baseline drift due to their asymmetrical shape. In this study, three trapezoids are synthesized as a symmetrical zero-area (SZA) shape, which can remove the DC offset and restrain the baseline drift. This baseline restoration technique can be easily implemented in digital pulse processing (DPP) systems base on the recursive algorithm. To strengthen our approach, the iron's characteristic x-ray was detected using a Si-PIN diode detector. Compared with traditional trapezoidal pulse shapers, the SZA trapezoidal pulse shaper improved the energy resolution from 237eV to 216eV for the 6.403keV Kα peak.

High-performance vertical Si PiN diode by hole remaining mechanism

A novel diode with a unique trench shape is predicted by TCAD simulation to have high performance. The novel 600V vertical PiN diode with hole pockets by the Bosch deep trench process shows a better trade-off curve between reverse recovery loss and forward voltage. The reverse recovery loss is reduced by half. In addition, the active chip size of the novel diode is reduced to two-thirds that of the conventional PiN diode in the same forward voltage. Thanks to the hole pockets with an electric field in the diagonal direction, the remaining hole suppresses the surge voltage with noise for high performance. In this paper, we specially focus on the analysis of phenomenon and the noise suppression mechanism during reverse recovery. The novel diode structure is a strong candidate when developing the fabrication process after silicon trench etching is established.

SiC SBDs selection method based on loss analysis of boost converter

Silicon carbide schottky barrier diodes (SiC SBDs) have much better characteristic than Si PiN diode in high voltage applications because SiC SBDs do not have recovery effect. However, simple replacing is not the most effective way. In a boost converter, the power loss caused by the SiC SBD can be divided into the conduction loss of the SiC SBD and the loss caused by the energy stored in the junction capacitance of the SiC SBD. Therefore analysis of not only the conduction loss but also the loss caused by the energy stored in the junction capacitance of the SiC SBD can realize the SiC SBD selection to improve the efficiency of the boost converter. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Time-of-flight measurements of heavy ions using Si PIN diodes

A new off-line timing method for PIN diode signals is presented which allows the plasma delay effect to be suppressed. Velocities of heavy ions measured by the new method are in good agreement within a wide range of masses and energies with velocities measured by time stamp detectors based on microchannel plates.

Experimental testing of heavy ions mass search procedure in the measurements with PIN diodes

We discuss the quality of heavy ions (HI) mass reconstruction in the wide range of HI energies and masses using Si PIN diodes for measuring both energy and time-of-flight. The results are based on the experimental data obtained at the IC-100 accelerator in the Flerov Laboratory of the JINR (Dubna, Russia).

MeV-SIMS yield measurements using a Si-PIN diode as a primary ion current counter

Megaelectronvolt-Secondary Ion Mass Spectrometry (MeV-SIMS) is an emerging Ion Beam Analysis technique for molecular speciation and submicron imaging. Various setups have been constructed in the recent years. Still a systematic investigation on the dependence of MeV-SIMS yields on different ion beam parameters is missing. A reliable measurement method of the beam current down to the attoampere range is needed for this investigation. Therefore, a new detector has been added to the MeV-SIMS setup at the Ruđer Bošković Institute (RBI), which measures the current directly using a Si PIN-diode. In this work, we present the constructed system, its characteristics, and results of the first yield measurements. These measurements have already identified important factors that have to be considered while constructing a MeV SIMS setup.

Study of the development of defects in Si PIN diodes exposed to 23 GeV/c protons

Studying the development of crystallographic defects in PIN diodes is the focus of the RD-50 (CERN) research project. The study was carried out on Si PIN diodes manufactured and used in the Czech Republic. The Si PIN diodes were irradiated with 23 GeV/c protons at doses ranging from 0.5 to 43 Gy. The Si PIN diodes were calibrated in a 23 GeV/c proton source [1], and the energy traps of the defects produced were measured by the DLTS method. The IV characteristics and the parameters of the defects were studied. The 23 GeV/c protons produce typical crystallographic defects and, at higher doses, bring about their regrouping thus giving rise to a new generation of defects. Defects are classified by their energy levels in the forbidden band from the conduction band. The mechanism influencing the parameters of the defects is discussed. The study of defects in silicon is important for silicon-based electronic elements used in cosmic research because of their effects on the operability and reliability of electronic equipment installed in satellites. Another application is the dosimetry measurements involving various types of particle accelerators.