Modeling of Radiation Damage Effects in Silicon Detectors at High Fluences HL-LHC with Sentaurus TCAD

In this work we propose the application of an enhanced radiation damage model based on the introduction of deep level traps / recombination centers suitable for device level numerical simulation of silicon detectors at very high fluences (e.g. 2.0x10E16 1 MeV equivalent neutrons/cm2). We present the comparison between simulation results and experimental data for p-type substrate structures in different operating conditions (temperature and biasing voltages) for fluences up to 2.2x10E16 neutrons/cm2. The good agreement between simulation findings and experimental measurements fosters the application of this modeling scheme to the optimization of the next silicon detectors to be used at HL-LHC.Comment: Supported by the H2020 project AIDA-2020, GA no. 65416

Numerical Modelling of Polycrystalline Diamond device for Advanced Sensor Design

Abstract Technology Computer Aided Design (TCAD) simulation tools are routinely adopted within the design flow of semiconductor devices to simulate their electrical characteristics. However, the device level simulation of diamond is not straightforward within the state-of-the-art TCAD tools. Physical models have to be specifically formulated and tuned for single-crystal CVD (scCVD) and polycrystalline (pcCVD) diamond in order to account for, among others, incomplete ionization, intrinsic carrier free material, dependences of carrier transport on doping and temperature, impact ionization, traps and recombination centers effects. In this work, we propose the development and the application of a numerical model to simulate the electrical characteristics of polycrystalline diamond conceived for sensors fabrication. The model is based on the introduction of an articulated, yet physically based, picture of deep-level defects acting as recombination centers and/or trap states. This approach fosters the exploration and optimization of innovative semiconductor devices conjugating the capabilities of CMOS electronics devices and the properties of diamond substrates, e.g. for biological sensor applications or single particle detectors for High Energy Physics experiments

Timing Performances and Radiation Hardness of 3D Diamond Detectors

n/

Fabrication and Characterisation of 3D Diamond Pixel Detectors With Timing Capabilities

Diamond sensors provide a promising radiation hard solution to the challenges posed by the future experiments at hadron machines. A 3D geometry with thin columnar resistive electrodes orthogonal to the diamond surface, obtained by laser nanofabrication, is expected to provide significantly better time resolution with respect to the extensively studied planar diamond sensors. We report on the development, production, and characterisation of innovative 3D diamond sensors achieving 30% improvement in both space and time resolution with respect to sensors from the previous generation. This is the first complete characterisation of the time resolution of 3D diamond sensors and combines results from tests with laser, beta rays and high energy particle beams. Plans and strategies for further improvement in the fabrication technology and readout systems are also discussed

A Hydrogenated amorphous silicon detector for Space Weather Applications

The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of large energetic proton events up to hundreds of MeV. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and in space weather science and applications. The critical flux detection threshold for solar X rays, soft gamma rays, electrons and protons is discussed in detail.Comment: 32 pages, 13 figures, submitted to Experimental Astronom

Editorial: Precision detectors and electronics for fast timing: Advances and applications

International audienceEditorial on the Research Topic: Precision Detectors and Electronics for Fast Timing: advances and application

Modeling of Radiation Damage Effects at HighLuminosity LHC Expected Fluences: Measurements and Simulations

International audienceA practical, yet physically grounded, TCAD modeling approach to study the radiation damage effects on silicon detectors exposed to the very high fluences expected at High Luminosity LHC (greater than 2.2×10 16 1MeV n eq /cm 2 ) is presented in this work. The modeling strategy is based on combined bulk and surface damage effects accounting for a limited number of measurable parameters. Starting from standard test structure measurements (i.e. MOS capacitors, gated diodes and MOSFETs), the most relevant parameters able to describe the complex phenomena related to the damage effects at these very high fluences have been extracted and therefore fed as input to the simulation tools. In particular the properties of the SiO 2 layer and of the SiO 2 /Si interface have been deeply investigated on high-resistivity n-type and p-type silicon test structures, before and after irradiation with X-rays in the range from 50 krad(SiO 2 ) to 20 Mrad(SiO 2 ). Thus the extrapolated dose-dependent parameters (e.g. interface trap density and oxide charge density) have been straight included in the TCAD modeling scheme. The adopted numerical approach has been validated by means of the comparison between simulation results and experimental data. To this purpose, steady-state and small signal analysis have been selected as reference analyses to assess the model suitability along with the charge collection efficiency. Different technology and design options/detector geometries can be therefore evaluated, from conventional planar pixelated (strip/pixel) detectors to active-edges or 3D (columnar electrodes) detectors, as well different principle of operation such as charge multiplication in Low Gain Avalanche Detector. This would support technology independence of the model and its use as a predictive tool for the design and the optimization of new classes of silicon sensors for the next generation High-Energy Physics experiments

Measurements of surface and bulk radiation damage effects in silicon detectors for Phase-2 CMS Outer Tracker

In this work we address the effects of bulk and surface damages on detectors fabricated by Hamamatsu on standard float zone (FZ) p-type material with an active thickness of 290 $\mu$m or thinned to 240 $\mu$m. In order to disentangle the effects of the two main radiation damage mechanisms, ionization effects and atomic displacement, the structures underwent two types of radiation: X-ray with doses from 0.05 to 70 Mrad (SiO$_2$) and neutron in the range of 1$-$10 $\times$ 10$^{14}$ n$_{eq}$/cm$^2$ 1 MeV equivalent. The combined surface and bulk damage could be investigated in structures that underwent both types of irradiation. A wide set of measurements has been carried out on the test structures for a complete characterization.In this work we address the effects of bulk and surface damages on detectors fabricated by Hamamatsu on standard float zone (FZ) p-type material with an active thickness of 290 µm or thinned to 240 µm. In order to disentangle the effects of the two main radiation damage mechanisms, ionization effects and atomic displacement, the structures underwent two types of radiation: X-ray with doses from 0.05 to 70 Mrad (SiO 2 ) and neutron in the range of 1 − 10 × 10 14 n eq /cm 21MeV equivalent. The combined surface and bulk damage could be investigated in structures that underwent both types of irradiation. A wide set of measurements has been carried out on the test structures for a complete characterization