Design optimization of ultra-fast silicon detectors Cartiglia, N.; Arcidiacono, R.; Baselga, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2015, Volume:
796
Journal Article
Peer reviewed
Open access
Low-Gain Avalanche Diodes (LGAD) are silicon detectors with output signals that are about a factor of 10 larger than those of traditional sensors. In this paper we analyze how the design of LGAD can ...be optimized to exploit their increased output signal to reach optimum timing performances. Our simulations show that these sensors, the so-called Ultra-Fast Silicon Detectors (UFSD), will be able to reach a time resolution factor of 10 better than that of traditional silicon sensors.
We designed, produced, and tested RSD (Resistive AC-Coupled Silicon Detectors) devices, an evolution of the standard LGAD (Low-Gain Avalanche Diode) technology where a resistive n-type implant and a ...coupling dielectric layer have been implemented. The first feature works as a resistive sheet, freezing the multiplied charges, while the second one acts as a capacitive coupling for readout pads. We succeeded in the challenging goal of obtaining very fine pitch (50, 100, and 200 μm) while maintaining the signal waveforms suitable for high timing and 4D-tracking performances, as in the standard LGAD-based devices.
4D tracking: present status and perspectives Cartiglia, N.; Arcidiacono, R.; Costa, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2022, Volume:
1040
Journal Article
Peer reviewed
Open access
The past ten years have seen the advent of silicon-based precise timing detectors for charged particle tracking. The underlying reason for this evolution is a design innovation: the Low-Gain ...Avalanche Diode (LGAD). In its simplicity, the LGAD design is an obvious step with momentous consequences: low gain leads to large signals maintaining sensors stability and low noise, allowing sensor segmentation. Albeit introduced for a different reason, to compensate for charge trapping in irradiated silicon sensors, LGAD found fertile ground in the design of silicon-based timing detectors. Spurred by this design innovation, solid-state-based timing detectors for charged particles are going through an intense phase of R&D, and hybrid and monolithic sensors, with or without internal gain, are being explored. This contribution offers a review of this booming field.
LGAD designs for Future Particle Trackers Cartiglia, N.; Arcidiacono, R.; Borghi, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2020, Volume:
979, Issue:
C
Journal Article
Peer reviewed
Open access
Several future high-energy physics facilities are currently being planned. The proposed projects include high energy e+e− circular and linear colliders, hadron colliders, and muon colliders, while ...the Electron–Ion Collider (EIC) is expected to construct at the Brookhaven National Laboratory in the future. Each proposal has its advantages and disadvantages in terms of readiness, cost, schedule, and physics reach, and each proposal requires the design and production of specific new detectors. This paper first presents the performances necessary for future silicon tracking systems at the various new facilities. Then it illustrates a few possibilities for the realization of such silicon trackers. The challenges posed by the future facilities require a new family of silicon detectors, where features such as impact ionization, radiation damage saturation, charge sharing, and analog read-out are exploited to meet these new demands.
This paper summarizes the beam test results obtained with a Resistive Silicon Detector (RSD) (also called AC-Low Gain Avalanche Diode, AC-LGAD) pixel array tested at the DESY beam test facility with ...a 5 GeV/c electron beam. Furthermore, it describes in detail the simulation results of DC-RSD, an evolution of the RSD design. The simulations campaign described in this paper has been instrumental in the definition of the structures implemented in the Fondazione Bruno Kessler FBK first DC-RSD production.
The RSD matrix used in this study is part of the second FBK RSD production, RSD2. The best position resolution reached in this test is σx=15μm, about 3.4% of the pitch. DC-RSD LGAD, are an evolution of the AC-coupled design, eliminating the dielectric and using a DC-coupling to the electronics. The concept of DC-RSD has been finalized using full 3D Technology-CAD simulations of the sensor behavior. TCAD simulations are an excellent tool for designing this innovative class of detectors, enabling the evaluation of different technology options (e.g., the resistivity of the n+ layer, contact materials) and geometrical layouts (shape and distance of the read-out pads).
In this paper we report on the timing resolution obtained in a beam test with pions of 180 GeV/c momentum at CERN for the first production of 45 μm thick Ultra-Fast Silicon Detectors (UFSD). UFSD are ...based on the Low- Gain Avalanche Detector (LGAD) design, employing n-on-p silicon sensors with internal charge multiplication due to the presence of a thin, low-resistivity diffusion layer below the junction. The UFSD used in this test had a pad area of 1.7 mm2. The gain was measured to vary between 5 and 70 depending on the sensor bias voltage. The experimental setup included three UFSD and a fast trigger consisting of a quartz bar readout by a SiPM. The timing resolution was determined by doing Gaussian fits to the time-of-flight of the particles between one or more UFSD and the trigger counter. For a single UFSD the resolution was measured to be 34 ps for a bias voltage of 200 V, and 27 ps for a bias voltage of 230 V. For the combination of 3 UFSD the timing resolution was 20 ps for a bias voltage of 200 V, and 16 ps for a bias voltage of 230 V.
Ultra-fast silicon detectors (UFSD) Sadrozinski, H.F.-W.; Anker, A.; Chen, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2016, Volume:
831, Issue:
C
Journal Article
Peer reviewed
Open access
We report on measurements on Ultra-Fast Silicon Detectors (UFSD) which are based on Low-Gain Avalanche Detectors (LGAD). They are n-on-p sensors with internal charge multiplication due to the ...presence of a thin, low-resistivity diffusion layer below the junction, obtained with a highly doped implant. We have performed several beam tests with LGAD of different gain and report the measured timing resolution, comparing it with laser injection and simulations. For the 300μm thick LGAD, the timing resolution measured at test beams is 120ps while it is 57ps for IR laser, in agreement with simulations using Weightfield2. For the development of thin sensors and their readout electronics, we focused on the understanding of the pulse shapes and point out the pivotal role the sensor capacitance plays.
First FBK production of 50 μm ultra-fast silicon detectors Sola, V.; Arcidiacono, R.; Boscardin, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2019, Volume:
924
Journal Article
Peer reviewed
Open access
Fondazione Bruno Kessler (FBK, Trento, Italy) has recently delivered its first 50 μm thick production of Ultra-Fast Silicon Detectors (UFSD), based on the Low-Gain Avalanche Diode design. These ...sensors use high resistivity Si-on-Si substrates, and have a variety of gain layer doping profiles and designs based on Boron, Gallium, Carbonated Boron and Carbonated Gallium to obtain a controlled multiplication mechanism. Such variety of gain layers will allow identifying the most radiation hard technology to be employed in the production of UFSD, to extend their radiation resistance beyond the current limit of ϕ∼ 1015 neq/cm2. In this paper, we present the characterisation, the timing performance, and the results on radiation damage tolerance of this new FBK production.
This paper presents the measurement of the spatial and temporal resolutions of a Resistive Silicon Detector (RSD) pixel matrix read out by the FAST2 ASIC, a 16-channel fully custom amplifier ...developed by INFN Torino using a 110 nm CMOS technology. The test was performed at the DESY test beam facility with a 5 GeV/c electron beam. The RSD matrix is composed of seven 450 μm pitch pixels with cross-shaped electrodes for a total area of about 1.5 mm2. The position resolution reached is σx=14± 1 μm, approximately 3.5% of the pitch, and the temporal resolution is σt= 49 ± 6 ps. The work demonstrates that RSD sensors with cross-shaped electrodes achieve 100% fill factor and homogeneous resolutions over the whole matrix surface, making them a suitable choice for 4D tracking applications.
Long-distance signal propagation in AC-LGAD Bishop, C.; Das, A.; Ding, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
July 2024, 2024-07-00, Volume:
1064
Journal Article
Peer reviewed
Open access
We investigate the signal propagation in AC-LGAD (aka RSD), which are LGAD with a common N+ layer and segmented AC-coupled readout contacts, by measuring the response to IR laser TCT on a large ...selection of AC-LGAD with strip readout. The interest for this topic derives from the realization that while large charge sharing between neighboring strips is essential for good position resolution, large sharing beyond the next neighbor generates background signals which in general are detrimental to the sensor goal of low occupancy. Using AC-LGAD with strip readout produced by Hamamatsu Photonics (HPK), we evaluate the effects of a variety of sensor properties, including geometrical parameters (strip length, width), process parameters like the N+ layer resistivity, the coupling capacitance, and the thickness of the bulk on the signal sharing and the position resolution.
•AC-LGAD are a new form of Ultra-Fast Silicon Detectors.•They have highly segmented readout reducing power consumption.•Signal sharing leads to high precision temporal and spatial resolution.
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