Particle detectors for operation at future high-energy collider
experiments are designed in view of both their facilities' physics
objectives and their experimental conditions, which differ substantially between lepton and hadron colliders as well as between linear and circular colliders. Example differences are background conditions and duty cycles, which for instance translate into very...
Dark Matter In CCDs (DAMIC) is a silicon detector apparatus used primarily for searching for low-mass dark matter using the silicon bulk of Charge-Coupled Devices (CCDs) as targets. The silicon target within each CCD is 675 µm thick and its top surface is divided into over 16 million 15 µm x 15 µm pixels. The DAMIC collaboration has installed and operated seven of these CCDs at SNOLAB,...
The tracking performance of the ATLAS detector relies critically on its 4-layer
Pixel Detector, that has undergone significant hardware and readout upgrades to
meet the challenges imposed by the higher collision energy, pileup and
luminosity that are being delivered by the Large Hadron Collider (LHC), with
record breaking instantaneous luminosities of 2 x 1034 cm-2 s-1...
An upgraded silicon pixel detector has been installed in 2017 in the Compact Muon Solenoid (CMS) to cope with the harsh environment of the even increased luminosity of the proton-proton collisions at the Large Hadron Collider (LHC) and maintain high tracking performance at instantaneous luminosities of $2\times 10^{34} cm^{-2}s^{-1}$, and fluences up to $1\times 10 ^{15} n_{eq}/cm^2$. The...
In HL-LHC operation the instantaneous luminosity will reach unprecedented values, resulting in about 200 proton-proton interactions in a typical bunch crossing. The current ATLAS Inner Detector will be replaced by an all-silicon system, the Inner Tracker (ITk). The innermost part of ITk will consist of a state-of-the-art pixel detector.
Several different silicon sensor technologies will be...
The High Luminosity Large Hadron Collider (HL-LHC) at CERN is expected to collide protons at a centre-of-mass energy of 14 TeV and to reach the unprecedented peak instantaneous luminosity of $5-7.5\times10^{34} cm^{-2}s^{-1}$ with an average number of pileup events of 140-200. This will allow the ATLAS and CMS experiments to collect integrated luminosities up to 3000-4000 fb$^{-1}$ during the...
The upgrade of the LHCb experiment, planned for 2020, will transform the experiment to a trigger-less system reading out the full detector at the LHC collision rate and up to $2\times 10^{33}cm^{−2} s^{-1}$ instantaneous luminosity.
As part of the LHCb Upgrade, hybrid pixel prototypes have been studied in detail at SPS testbeams using the Timepix3 Telescope. A range of prototype planar...
The High Luminosity Large Hadron Collider (HL-LHC) at CERN is expected to collide protons at a centre-of-mass energy of 14 TeV and to reach the unprecedented peak instantaneous luminosity of $5-7.5\times10^{34} cm^{-2}s^{-1}$ with an average number of pileup events of 140-200. This will allow the ATLAS and CMS experiments to collect integrated luminosities up to 3000-4000 fb$^{-1}$ during the...
The ATLAS experiment at the Large Hadron Collider is currently preparing for a major
upgrade of the Inner Tracking for the Phase-II LHC operation (known as HL-LHC), scheduled
to start in 2026. In order to achieve the integrated luminosity of 4000 fb-1, the instantaneous
luminosity is expected to reach unprecedented values, resulting in about 200 proton-proton
interactions in a typical...
In view of the LHC upgrade phases towards the High Luminosity LHC (HL-LHC), the ATLAS experiment plans to upgrade the Inner Detector with an all-silicon system.
The n-on-p silicon technology is a promising candidate to achieve a large area instrumented with
pixel sensors, since it is radiation hard and cost effective.
The paper reports on the performance of LPNHE thin n-on-p planar pixel...
The CMS Inner Tracker for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC) has to allow for tracking in a high track multiplicity environment caused by an instantaneous luminosity of up to $7.5 \times 10^{34}$ cm$^{-2}$ s$^{-1}$. In addition, the tracker has to tolerate 1 MeV neutron equivalent fluences $\phi_{eq}$ of up to $2 \times 10^{16}$ cm$^{-2}$ accumulating in the data...
The CMS pixel detector upgrade for the HL-LHC must withstand unprecedented radiation fluence, up to $2\times 10^{16}$ neutron-equivalent per cm$^2$ over the lifetime of the detector. Sensors and the RD53A prototype readout chip have been developed to deliver the needed performance, but their radiation hardness at the full expected fluence still needs to be demonstrated. We have extensively...
Nowadays silicon strip sensors in high luminosity experiments usually consist of a p-doped bulk with n-type strip implants.
General consensus is that such a design requires an additional interstrip isolation structure like a p-stop implant.
If no additional implant is implemented between the strips, it is expected that the interstrip resistance will be insufficient before and especially...
The segmented n-on-p sensors require isolation implants to prevent the electrodes from electrically shorting and two isolation configurations are being considered for the high granularity endcap calorimeter (HGCAL) of CMS at the high luminosity LHC: common and individual (atoll) p-stops. Performance of the two p-stop options after irradiation is the focus of this study. We present a...
The ATLAS experiment at the Large Hadron Collider is currently preparing for a major
upgrade of the Inner Tracking for the Phase-II LHC operation (known as HL-LHC), scheduled
to start in 2026. In order to achieve the integrated luminosity of 4000 fb-1, the instantaneous
luminosity is expected to reach unprecedented values, resulting in about 200 proton-proton
interactions in a typical...
The CERN Large Hadron Collider (LHC) will undergo a major upgrade between 2025 and 2027, to increase the collision rate by a factor of about 5 compared to the present. Some existing components of the CMS detector - most notably the Tracker and Endcap Calorimeter - will have to be replaced to cope with the conditions of the high luminosity (HL-LHC) era: instantaneous peak luminosity up to...
The development of radiation hard, depleted monolithic active pixel sensors (DMAPS) over many years has led to full size detector matrices, realised in LFoundry 150 nm and TowerJazz 180 nm technologies.
Large and small electrode designs have been investigated and characterised, with different readout schemes, in a collaboration between Bonn-CERN-CPPM-IRFU. The talk will present the results of...
The MALTA (Monolithic pixel sensor from ALICE To ATLAS) is a monolithic silicon pixel sensor that has been designed in the 180 nm CMOS imaging process of TowerJazz. It was designed to be compatible with conditions like in the outermost pixel layer of the ATLAS ITk High Luminosity upgrade, with a required radiation hardness up to a fluence of $1\times 10^{15}\,n_{eq}/cm^2$ and a TID of...
With the upgrade of the inner tracking detector of the ATLAS experiment in 2026, the surface covered by hybrid pixel detectors increases from less than 2 m² at present to approximately 13 m². This makes sensor designs that utilize cost-effective, high-throughput CMOS processing lines with large and high-resistive wafers an attractive option. In addition, CMOS process features can be used to...
Major upgrades of the ALICE experiment are underway and will be completed during the LHC Long Shutdown 2 to enhance the physics capacities of ALICE for LHC Run3 and Run4. One key part of this upgrade is the new Inner Tracking System (ITS2), a CMOS monolithic active pixel sensor based pixel detector. The upgraded Inner Tracking System consists of three innermost layers (50 $\mu m$ thick...
Monolithic Active Pixel Sensors (MAPS) are used in many high energy physics experiments, also in ALICE at CERN. To find the most suitable geometry for the current ALICE inner tracking system (ITS2), several slight modifications had to be processed and lots of manual characterisation was done. This added high costs and time to the project. Using modern TCAD device simulation software combined...
Wafer-wafer bonding enables the fusion of two semiconductor wafers, without any additional material at the interface. In the context of pixel detectors, the method has the potential to enable limitless combinations of absorber materials with readout chips fabricated with CMOS technologies.
In this talk we present the status of our studies on the design, optimization and characterization of...
Low Gain Avalanche Detectors (LGADs) are silicon sensors with internal charge gain. The gain feature is used to improve the signal to noise ratio of the detector. These sensors are finding different applications including timing for high energy physics, beam monitoring for hadron therapy, and soft x-ray detection. This talk details the optimization of LGADs for different applications, with an...
Low Gain Avalanche Detectors (LGADs) are silicon detectors with modest internal gain (up to ~50) that allows the sensor to be very thin (20-50 um). LGADs are characterized by an extremely good time resolution (down to 17ps), a fast rise time (~500ps) and a very high repetition rate (~1ns full charge collection). In a broad array of fields, including particle physics (4-D tracking) and photon...
Resistive AC-LGAD (RSD) are sensors based on an evolution of the traditional LGAD designed aimed at eliminating the no-gain area between pads.
The principle of operation of RSD is based on the combination of 3 elements: the gain layer, a resistive n-doped junction contact, and the AC coupling. The design of RSD exploits the signal sharing among neighboring pads to achieve extremely good...
Measurements of Time of Arrival of particles in detectors with picosecond time accuracy is becoming fundamental for several applications worldwide. The future upgrade of High Luminosity LHC (HL-LHC) is one example where these measurements will be exploited to mitigate the pile-up effects generated by the increase of luminosity. Thanks to this tool, events overlapped in space but separated in...
Popcorn noise has been observed as a detrimental effect in LGADs operation under certain biasing conditions and is manifested as a random charge fluctuation in the detector output signal. We present a systematical analysis of popcorn noise studied in 35 and 50 μm thick CNM LGADs measured via TCT (Transient Current Technique) and a Sr-90 beta setup. The findings are used to define optimal bias...
The recently developed sensors based on the Low Gain Avalanche Diodes (LGAD) sensors [1,2], aka Ultra Fast Silicon Detectors (UFSD), provide excellent position measurement capabilities and additionally provide fast signal response with a precision better than 100ps [3]. These unique properties combined with high radiation hardness [4] and low production costs are very attractive for tracking...
Over the past decade, proton and ion-beam therapy has become an established form of cancer treatment. Currently, the achievable precision of this therapy is limited by uncertainties due to treatment planning based on conventional photon imaging. A significant effort is therefore invested into the development of proton or ion imaging modalities. A typical apparatus for such applications...
The Hamamatsu ORCA2 C11090-22B is a EM-CCD camera working with visible light, able to perform Ultra-Low Light Imaging. In this contribution, we will show how such a camera can be employed to study the breakdown of Silicon detectors by looking at their "hot spots", namely regions of a device that emit visible photons because of the high current densities flowing through them. We performed...
Radiotherapy with ions has become a diffuse tool for curing cancer. Despite scientific and technological advances to improve the treatment efficacy, several critical issues have yet to be addressed. In order to fully understand the biological effect of ions, a complete characterization of the radiation field is needed.
Microdosimetry has been identified as a powerful tool to tackle this...
Results of measurements with thin pad silicon detectors irradiated with reactor neutrons to 1e17 n/cm2 will be presented. Measurements were made with CNM LGAD pad detectors made on 75 um thick epitaxial layer on low resistivity support silicon. LGADs were chosen because this was the available set of thin pad detectors that could withstand high bias voltages. Edge-TCT, charge collection with...
Low Gain Avalanche Detectors (LGADs) are silicon detectors with modest internal gain (up to ~50) that allows the sensor to be very thin (20-50 um). LGADs are characterized by an extremely good time resolution (down to 17ps), a fast rise time (~500ps) and a very high repetition rate (~1ns full charge collection). These devices are relatively new but will be perfect candidates in a number of...
Present silicon sensor technology allows to efficiently operate sensors up to 10$^{16}$ n$_{eq}$/cm$^2$. However, several future applications, such as tracking detectors in high-luminosity and high-energy particle physics experiments, monitors for particle therapy and nuclear fusion reactors, envisage the use of silicon sensors in environments with fluences exceeding 10$^{17}$...
The CMS-TOTEM Precision Proton Spectrometer (PPS) consists of tracking and timing detectors installed along the LHC beam line between 210 and 220 m from the interaction point on both sides of the CMS experiment. The aim of the apparatus is to measure the position, direction and time-of-flight of protons which emerge intact from the pp collision. Fully integrated in the CMS data acquisition...
The High Luminosity upgrade of the CERN Large Hadron Collider (HL-LHC) will require new high-radiation tolerant silicon pixel sensors, capable of withstanding, in the innermost tracker layer, fluences up to $2.3\times 10^{16} n_{eq}/cm^2$ (1MeV equivalent neutrons). An extensive R&D program aiming at 3D pixel sensors, built with a top-side only process, has been put in place in CMS. A few...
3D pixel sensors are the technology of choice for the innermost layer (L0) of the ATLAS ITk detector at High Luminosity LHC. The considered sensors have pixel size of either 25 um x 100 um or 50 um x 50 um, with one read-out electrode at the center of a pixel and four bias electrodes at the corners. The former geometry has been chosen for the central part of L0 (barrel), the latter for the...
The Phase-II upgrade of the inner tracker of the CMS experiment is considering to use 3D pixel sensors for the innermost layers, given their intrinsic properties, well suited to resist the extreme radiation fluences expected at the High Luminosity Large Hadron Collider (HL-LHC). In this talk we present data collected from beam tests of 3D sensors bump-bonded to the RD53A prototype readout...
SINTEF MiNaLab recently completed its fifth fabrication run of full 3D pixel detectors with active-edges. The sensors were designed by the University of Oslo in collaboration with SINTEF within the Norwegian 3D detector collaboration. Sensors were fabricated on 6", Si-Si bonded wafers, with a device layer thickness of 150µm, using a single-sided processing approach. The production run included...
Developments on future tracking detectors go in the direction of a full 4D approach, in the sense of having both space and time measuring capabilities at the single pixel level. This is strongly motivated by the extremely high interaction intensities foreseen in the collider experiments of the next couple of decades and possibly beyond. Presently, no satisfactory technical solutions are...
We report the measurements of time resolution for double-sided 3D pixel sensors with a single cell of 50 {\mu}m x 50 {\mu}m fabricated at IMB-CNM. Measurements were conducted using a radioactive source at -20 and 20 degrees C in a bias voltage range of 50-200 V. The reference time was provided from an LGAD detector produced by Hamamatsu. Results are compared to previous measurements on...
The Belle II experiment at the super-B-factory SuperKEKB in Tsukuba, Japan started data taking in 2019. Its purpose is the measurement of electroweak phenomena and rare decays with unprecedented high precision. A up to 40-fold increase in instantaneous luminosity compared to the predecessor experiment Belle is targeted and will allow for recording a large dataset at the $\Upsilon(4S)$...
The peculiar features of SiPMs, such as their compact size, insensitivity to magnetic fields, low power consumption and mechanical robustness make them very promising as photosensors in calorimeters and precision timing detectors in the future generation of high energy physics experiments. In these contexts, a critical aspect is the radiation hardness of the silicon detector. Currently...
Silicon Photomultipliers (SiPMs) are very sensitive light detectors made by arrays of many Single-photon avalanche diodes (SPADs) connected in parallel. They are becoming more and more important in an increasing number of applications, such as high-energy physics experiments (e.g. photodetectors in the future upgrade of the CMS calorimeter) or more recently for reading out liquid noble-gasses...
A UV-sensitive SiPM incorporating an internal ALD filter is under development by a Caltech/FBK/emphasized textJPL group. The filter provides efficient detection of the 220 nm fast scintillation component of BaF$_2$ scintillation light together with strong discrimination of the larger 300 nm slow scintillation component. Measurements on a 6 mm $\times$ 6 mm device will be presented, including...
We present here the concept and results of a charged particle detector based on a novel inorganic scintillator coupled to a hybrid photodetector (HPD). The newly developed inorganic scintillator has a decay time ≤ 0.5 ns, high photon yield and long-lifetime. Together with the HPD, the detector exhibits a single electron pulse width of ≤ 0.7 ns, while allowing for quantitative detection over a...
In previous work, we have reported on the fabrication of pixel detectors on p-type magnetic Czochralski silicon substrates, employing a layer of aluminium oxide (Al2O3) grown by atomic layer deposition (ALD) as dielectric and field insulator. The high dielectric constant of Al2O3 facilitates implementation of capacitive coupling, which separates the signal from the significantly increased...
In silicon detectors, a fraction of the highly-doped region represents a dead layer, where the generated charge carriers are lost. By minimising the dead layer, this charge loss is minimised as well. This is important when the determination of the exact generated charge is crucial: e. g. in case of isotope identification with the $\Delta$E-E method or energy resolution measurements of...
IV and CV curves of are crucial measurements required to characterise silicon sensors. They have to be performed at reception and at several steps of particle detector modules assembly procedure to spot potential damages, at least in the prototyping phase.
High voltage (1kV) biasing of those sensors and accurate, low current measurements (50µA max) are mandatory for this. Typical instruments...
The LHC machine will be upgraded targeting a peak luminosity of $5-7.5\times10^{34}$cm$^{-2}$s$^{-1}$ and aiming to collect an integrated luminosity of $3000-4500\;$fb$^{-1}$ in 10 years. The Compact Muon Solenoid (CMS) silicon tracker (Inner Tracker, IT) will be replaced at the High Luminosity Large Hadron Collider (HL-LHC) upgrade by a new radiation-hard detector capable of handling higher...
P-type silicon strip sensors will be used as particle detectors in harsh radiation environment, as in the High Luminosity Large Hadron Collider with fluences up to $1\cdot10^{16}~n_{\mathrm{eq}}/\mathrm{cm}^2$. They have been irradiated and annealed to predict their long term performance. Charge multiplication, which appears at high voltages after long annealing times, increases the n charge...
Previously, fabrication of n+-in-p AC-coupled pixel detectors on p-type magnetic Czochralski silicon substrates at Micronova Nanofab facilities in Espoo, Finland has been reported. In our pixel detectors, we employ a layer of aluminum oxide (Al2O3) grown by atomic layer deposition (ALD) as dielectric and field insulator, instead of the commonly used SiO2. The high dielectric constant and...
