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The High Luminosity upgrade of the CERN LHC collider (HL-LHC) demands a new high-radiation–tolerant solid-state pixel sensor capable of surviving fluencies up to a few 10$^{16} n_{eq}/\mathrm{cm}^2$ at ∼ 3 cm from the interaction point. To this extent the INFN ATLAS-CMS joint research activity, in collaboration with Fondazione Bruno Kessler (FBK), is aiming at the development of thin $n$-in-$p$–type pixel sensors for the HL-LHC. The R&D; covers both planar and single-sided 3D columnar pixel devices made with the Si-Si Direct Wafer Bonding technique, which allows for the production of sensors with 100 μm and 130 μm active thickness for planar sensors, and 130 μm for 3D sensors, the thinnest ones ever produced so far. The first prototypes of hybrid modules, bump-bonded to the present CMS readout chip, have been tested on beam. The first results on their performance before and after irradiation are presented

Silicon carbide (SiC) is a compound semiconductor, which is considered as a possible alternative to silicon for particles and photons detection. Its characteristics make it very promising for the next generation of nuclear and particle physics experiments at high beam luminosity. Silicon Carbide detectors for Intense Luminosity Investigations and Applications (SiCILIA) is a project starting as a collaboration between the Italian National Institute of Nuclear Physics (INFN) and IMM-CNR, aiming at the realization of innovative detection systems based on SiC. In this paper, we discuss the main features of silicon carbide as a material and its potential application in the field of particles and photons detectors, the project structure and the strategies used for the prototype realization, and the first results concerning prototype production and their performance.

Thirty-three-thousand CLARO8 ASICs were produced in 0.35μm CMOS technology and will be installed in the upgraded LHCb detector at CERN. Radiation hardness has been extensively characterized and compared to prototype production.

Photon detectors capable of operating in high photon rate environments are required for next generation ring imaging Cherenkov (RICH) detectors at high luminosity accelerators, like HL-LHC. These photodetectors will have to sustain single photon rate in excess of 1 GHz∕cm 2 , while being able to resist to high radiation levels of several Mrad and a 1 MeV-equivalent neutron fluence up to 10 14 n eq ∕ cm 2 . The characteristics of latest models of commercial silicon photomultipliers (SiPMs) and micro-channel plates photomultiplier tubes (MCP-PMT) are investigated in order to verify whether they satisfy the required performance, with particular emphasis on radiation hardness and high rate operation. Their innovative characteristics require tailored front-end electronics, whose architecture can be adapted to deal with higher pixel occupancy, as it will be described.

Optical properties and irradiation resistance of heavy metal oxide tellurite glasses in the TeO2-PbO-Bi2O3-B2O3 system doped with different ions are investigated. The results indicate that the matrix glass has a moderate UV cut-off edges at about 386 nm wavelength. The UV cut-off positions are obviously shifted to red by the addition of Ce4+. The introduction of Cr3+, Ce4+ and Ni2+ into the matrix glass exerts positive influences on irradiation resistance of glasses and cerium plays the most pronounced role. Such phenomena are mainly attributed to the variable valences of these cations. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Simultaneous photon beam position and intensity monitoring is becoming of increasing importance for new generation synchrotron radiation sources and free electron lasers (FEL). Thus, novel concepts of beam diagnostics are required in order to keep such beams under control. From this perspective diamond is a promising material for the production of semitransparent in situ photon beam monitors, which can withstand the high dose rates occurring in such radiation facilities. Here, we report on the development of freestanding, single-crystal chemical-vapor-deposited diamond detectors with segmented electrodes. Due to their direct, low-energy band gap, InGaAs quantum well devices operated at room temperature may also be used as fast detectors for photons ranging from visible to X-ray. These features are valuable in low-energy and time-resolved FEL applications. In particular, a novel segmented InGaAs/InAlAs device has been developed and will be discussed. Dedicated measurements carried out on both these devices at the Elettra Synchrotron show their capability to monitor the position and the intensity of the photon beam with bunch-by-bunch temporal performances. Furthermore, preliminary tests have been performed on diamond detectors at the Fermi EEL, extracting quantitative intensity and position information for 100-fs-wide FEL pulses with a photon energy of 28.8 eV. (C) 2013 Elsevier B.V. All rights reserved

In recent years, the sol-gel technique was proven to allow a good control, at a relatively low densification temperature, of rare earth (RE) ions incorporation and of their dispersion inside the glass matrix. The glass synthesis can be performed by using high purity precursors, reducing the level of unwanted impurities, which is an essential feature for the radiation hardness of such materials. Several studies demonstrated that RE-doped silica glasses prepared by sol-gel route are suitable materials for the realization of scintillating optical fibers, and have application perspectives as wavelength shifters for the collection and transport of scintillation light in High Energy Physics (HEP) experiments. Moreover, the use of RE-doped fibers as scintillators in HEP detectors, possibly in parallel with undoped fibers exploiting Cherenkov light, has been recently proposed. An extremely good radiation resistance and fast response are crucial properties for such application. In this work we present a detailed study of the scintillation properties of SiO2: 0.05 mol% Ce glasses and the results of irradiation tests using gamma-rays from a 60Co source and X-rays up to an integrated dose of 1 kGy. Radio-luminescence investigations have been combined with optical absorption and attenuation length measurements before and after irradiation with X-rays and with 60Co gamma-rays. Comparisons between bulk preforms and fibers have been carried out, in order to disclose the role of the fiber drawing process in the radiation hardness properties. Fibers with a lower (0.0125 mol%) Ce concentration have also been considered, pointing to a reduction of the radiation damage related to the decrease of the dopant concentration. Fibers with fluorinated glass or polymeric cladding have been compared, looking towards a future engineering of the fiber structure to improve the light propagation and the radiation resistance. The evolution of the optical absorption spectra and of the attenuation length as a function of time after irradiation has been investigated in order to understand the room temperature stability of radiation-induced point defects acting as color centers. Moreover, the samples have been subjected to thermal annealing cycles, to check the temperature activated carrier release from radiation-induced defects and the possibility of a complete recovery of the damage. Further analyses on the properties of sol-gel silica fibers have been carried out: the homogeneity of the Ce distribution along the fiber length has been tested by means of the X-ray fluorescence technique. Eventually, we will report the results of the forthcoming test of Ce-doped fibers, assembled in a calorimeter prototype, with GeV electron beams at the CERN test beam facilities, to better investigate the application perspectives of such kind of material as scintillator in High Energy Physics detectors. This work has been supported by the H2020 projects AIDA-2020 (GA no. 654168) and INTELUM (GA no. 644260).

Fluorinated silica glasses with improved vacuum ultraviolet (VUV) transmittance have been synthesized following a sol-gel route starting from fluorinated alkoxide precursors. Matrix dehydration and fluorination have been investigated by Raman, IR, and refractive index measurements. The results show that, during the densification step, the residual hydroxyl and fluorine content can be controlled by governing the kinetic equilibrium between matrix collapse and fluorine evolution. This highlights the pivotal role of in situ reactions of fluorine-containing molecular precursors in the networking mechanism of a sol-gel material after thermal activation. Superior VUV transmittance and radiation hardness with respect to pure commercial silica and undoped sol-gel silica have been confirmed by synchrotron light absorption measurements before and after X-ray exposure. These properties make the material very attractive for applications in VUV photolithography technologies and optical fibers, especially for use in environments with a high level of ionizing radiation, such as spacecrafts and nuclear power plants.

We report on the functional characterization of the first batch of 3D Double-Sided Double Type Column (3D-DDTC) detectors fabricated at FBK, Trento. This detector concept represents the evolution of the previous 3D-STC detectors towards full 3D detectors, and is expected to achieve a performance which is comparable to standard 3D detectors, but with a simpler fabrication process. Measurements were performed on detectors in the microstrip configuration coupled to the ATLAS ABCD3T binary readout. This paper reports spatially resolved signal efficiency tests made with a pulsed infrared laser setup and charge collection efficiency tests made with a Beta source.

This paper presents a DC-DC converter to be embedded in the pixel front-end of detectors in Large Hadron Collider (LHC) experiment at CERN. The DC-DC converter has to operate in a hostile environment due to the radiation. Under radiation, the value of the resistances, R on , of the MOS switches changes. In addition, the load current, I out , can change, ranging around the nominal value of 400mA from 200mA to 600mA. Both R on and I out , determine the optimum frequency that maximize the efficiency. In order to improve the efficiency as the operation conditions of the DC-DC converter changes, a tracking circuit of the peak efficiency was implemented. The tracking circuit performs a closed loop control of the clock frequency of the DC-DC converter. This converter provides an 800mV output voltage from a 1.2V input supply reaching an 80.22% peak efficiency. It is integrated in 65nm bulk CMOS technology with an area of 1.31mm2.

Beyond their important economic role in commercial communications, satellites in general are critical infrastructure because of the services they provide. In addition to satellites providing information which facilitates a better understanding of the space environment and improved performance of physics experiments, satellite observations are also used to actively monitor weather, geological processes, agricultural development and the evolution of natural and man-made hazards. Defence agencies depend on satellite services for communication in remote locations, as well as for reconnaissance and intelligence. Both commercial and government users rely on communication satellites to provide communication in the event of a disaster that damages ground-based communication systems, provide news, education and entertainment to remote areas and connect global businesses. The space radiation environment is an hazard to most satellite missions and can lead to extremely difficult operating conditions for all of the equipment travelling in space. Here, we first provide an overview of the main components of space radiation environment, followed by a description of the basic mechanism of the interaction of radiation with matter. This is followed by an introduction to the space radiation hardness assurance problem and the main effects of natural radiation to the microelectronics (total ionizing dose, displacement damage and the single-event effect and a description of how different effects occurring in the space can be tested in on-ground experiments by using particle accelerators and radiation sources. We also discuss standards and the recommended procedures to obtain reliable results.

The Belle-II VerteX Detector (VXD) has been designed to improve the performances with respect to Belle and to cope with an unprecedented luminosity of 8 × 10 35 cm − 2 s − 1 achievable by the SuperKEKB. Special care is needed to monitor both the radiation dose accumulated throughout the life of the experiment and the instantaneous radiation rate, in order to be able to promptly react to sudden spikes for the purpose of protecting the detectors. A radiation monitoring and beam abort system based on single-crystal diamond sensors is now under an active development for the VXD. The sensors will be placed in several key positions in the vicinity of the interaction region. The severe space limitations require a challenging remote readout of the sensors.

The extremely harsh conditions, in which the detectors will have to operate during the High Luminosity phase of the Large Hadron Collider at CERN, set stringent requirements on the properties of the scintillators which can be used. Among different scintillating materials under study, inorganic crystals such as LuAG:Ce and YAG:Ce represent good candidates for such application. A detailed investigation of the radiation hardness of LuAG:Ce and YAG:Ce crystal samples ( $1 \times 1 \times 1 ~\hbox{cm}^3$ cubes) produced by Crytur is presented in this study. Given their potential in many calorimeter designs, YAG:Ce samples with high aspect ratio ( $1 \times 1 \times 14 ~\hbox{cm}^3$ ) have also been tested. Optical and scintillating properties of the samples were studied before and after irradiation with different sources and at different intensities. Irradiation with gamma-rays to the doses of 1 and 100 kGy and with 24 GeV protons up to an integrated fluence of ${10^{14}}~\hbox{cm}^{ - 2}$ were performed at CERN. The scintillating properties of the crystals, as emission and excitation spectra and light yield remained unchanged after irradiation and only small levels of induced absorption were observed. The results obtained in this test confirm the potential of LuAG:Ce and YAG:Ce crystals as good candidates for calorimetry applications in future high energy physics experiments.

The CLARO-CMOS is a prototype ASIC that allows fast photon counting with low power consumption, built in AMS 0.35 μm CMOS technology. It is intended to be used as a front-end readout for the upgraded LHCb RICH detectors. In this environment, assuming 10 years of operation at the nominal luminosity expected after the upgrade, the ASIC must withstand a total fluence of about 6×10 12 1 MeV n eq /cm 2 and a total ionising dose of 400 krad. Long term stability of the electronics front-end is essential and the effects of radiation damage on the CLARO-CMOS performance must be carefully studied. This paper describes results of multi-step irradiation tests with protons up to the dose of ~8 Mrad, including measurement of single event effects during irradiation and chip performance evaluation before and after each irradiation step.

A high-speed charge-sensitive preamplifier (CSP) to be used in silicon calorimeters has been realized. The main features of this circuit are: high slew rate (larger than 500 V//spl mu/s), low noise, large output swing (5 V), high dynamic range (of the order of 90 dB), and 50-/spl Omega/ output drive capability. In addition, the CSP is designed to allow adaptation of its power-versus-noise performance to different experimental conditions. The bias current of the input device can be adjusted with an external component, in order to optimize the tradeoff between power consumption and noise. The power supply can be set in the 3.3-12-V range, optimizing the power dissipation over output swing ratio. The CSP was realized in a bipolar technology whose bipolar transistors have been previously tested before and after being subjected to irradiation. The results were taken into account in the design in order to achieve CSP radiation-hard performance.

The CLARO-CMOS is a prototype ASIC that allows fast photon counting with 5 ns peaking time, a recovery time to baseline smaller than 25 ns, and a power consumption of less than 1 mW per channel. This chip is capable of single-photon counting with multi-anode photomultipliers and finds applications also in the read-out of silicon photomultipliers and microchannel plates. The prototype is realized in AMS 0.35 micron CMOS technology. In the LHCb RICH environment, assuming 10 years of operation at the nominal luminosity expected after the upgrade in Long Shutdown 2 (LS2), the ASIC must withstand a total fluence of about 6×10 12 1 MeV n eq / cm 2 and a total ionizing dose of 400 krad. A systematic evaluation of the radiation effects on the CLARO-CMOS performance is therefore crucial to ensure long term stability of the electronics front-end. The results of multi-step irradiation tests with neutrons and X-rays up to the fluence of 10 14 cm −2 and a dose of 4 Mrad, respectively, are presented, including measurement of single event effects during irradiation and chip performance evaluation before and after each irradiation step.

The A-to-D converter here presented is part of a bigger system able to sense and monitor electrical/physical parameters in particles detectors, for LHC experiments. The CMOS integrated circuits operating in high-energy environments experience large leakage current and voltage/temperature variations. For this reason in LHC experiments, a proper sensing and monitoring system has been designed with the aim to provide real time information about the electrical/physical scenario for the detectors in LHC. The A-to-D converter has a resolution of 12 bits, is based on single slope architecture and is able to manage 32 input analog channels. The design is challenging for several reasons, considering the required conversion accuracy and the critical physical scenario. The entire A-to-D converter has been fully characterized with process-voltage-temperature variations, obtaining a definitive 11bit accuracy in the worst-case simulation corner. The A-to-D has been designed in CMOS 0.13 mu m technology, consumes 350 mu W (including dynamic power due to the digital circuits) and operates at 20MHz clock frequency, for a definitive 2.3kHz sample rate

We report radiation hardness tests performed, with a white neutron beam, at the Geel Electron LINear Accelerator in Belgium on silicon Photo-Multipliers. These are semiconductor photon detectors made of a square matrix of Geiger-Mode Avalanche photo-diodes on a silicon substrate. Several samples from different manufacturers have been irradiated integrating up to about 6.2 × 10 9 1-MeV-equivalent neutrons per cm2. © 2013 IEEE.

Single crystals of LuAG:Ce, LuAG:Pr and un-doped LuAG were grown by the vertical Bridgman method and studied for radiation hardness under gamma-rays with doses in the range 10–10 5 Gy ( 60 Co). A wide absorption band peaking at around 600 nm springs up in all three types of crystals after the irradiations. The second band peaking at around 375 nm appears in both LuAG:Pr and un-doped LuAG. Compositional variations have been done to reveal the spectral behavior of induced color centers in more detail and to understand their origin. Similarities in behavior of Yb 2+ centers in as-grown garnets are found, indicating that radiation induced color centers can be associated with residual trace amounts of Yb present in the raw materials. Un-doped LuAG and LuAG:Ce demonstrate moderate radiation hardness (the induced absorption coefficients being equal to 0.05–0.08 cm −1 for accumulated doses of 10 3 –10 4 Gy), while LuAG:Pr is less radiation hard. The ways to improve the radiation hardness are discussed.

Owing to their superior radiation hardness compared to planar detectors, 3D detectors are one of the most promising technologies for the LHC upgrade foreseen in 2017. Fondazione Bruno Kessler has developed 3D Double-side Double-Type Column (3D-DDTC) detectors providing a technological simplifications with respect to a standard 3D process while aiming at comparable detector performance. We present selected results from the electrical characterization of 3D-DDTC structures from the second batch made on p-type substrates, supported also by TCAD simulations.

Aim of this work is the description of a test equipment, designed to be integrated on board of a microsatellite, able to investigate the radiation tolerance of non-volatile memory arrays in a real flight experiment. An FPGA-based design was adopted to preserve a high flexibility degree. Besides standard Program/Read/Erase functions, additional features such as failure data screening and latch-up protection have been implemented. The instrument development phase generated, as a by-product, a non-rad-hard version of the instrument that allowed performing in-situ experiments using 60Co and 10 MeV Boron irradiation facilities on Ground. Preliminary measurement results are reported to show the instrumentation potential. © 2010 IEEE.

This report presents results on the optical transmission damage of undoped and Ce doped Y3Al5O12 scintillation crystals under high fluence of 24 GeV protons. We observed that, similarly to other middle heavy scintillators, it possesses the unique radiation hardness at fluence values as high as 5×1014 p/cm2 and it is thus promising for the application in the detectors at High Luminosity LHC. The crystalline structure of the garnet scintillator allows to control and further optimize its scintillation parameters, such as scintillation decay time and emission wavelength, and shows a limited set of the radioisotopes after the irradiation with protons.