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. 2.0×1016 1MeV 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 2.2×1016 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.
•Development of an enhanced TCAD radiation damage model.•Simulations of silicon detector behavior at very high fluences (e.g. 2×1016 n/cm2).•Application in different operating conditions (temperature and biasing voltages).•Validation through comparison with experimental data for p-type substrate devices.
The DC-coupled resistive silicon detectors (DC-RSD) are the evolution of the AC-coupled RSD (RSD) design, both based on the low-gain avalanche diode (LGAD) technology. The DC-RSD design concept ...intends to address a few known issues present in RSDs (e.g., baseline fluctuation and long tail-bipolar signals) while maintaining their advantages (e.g., signal spreading and 100% fill factor). The simulation of DC-RSD presents several unique challenges linked to the complex nature of its design and the large pixel size. The defining feature of DC-RSD, charge sharing over distances that can be as large as a millimeter, represents a formidable challenge for technology CAD (TCAD), the standard simulation tool. To circumvent this problem, we have developed a mixed-mode approach to the DC-RSD simulation, which exploits a combination of two simulation tools: TCAD and SPICE. Thanks to this hybrid approach, it has been possible to demonstrate that, according to the simulation, the key features of the RSD-excellent timing and spatial resolutions (few tens of picoseconds and few microns)-are maintained in the DC-RSD design. In this work, we present the developed models and methodology, mainly showing the results of device-level numerical simulation, which have been obtained with the state-of-the-art Synopsys Sentaurus TCAD suite of tools. Such results will provide all the necessary information for the first batch of DC-RSD produced by the Fondazione Bruno Kessler (FBK) foundry in Trento, Italy.
The very high radiation fluences expected at the high-luminosity large hadron collider (LHC) impose new challenges in terms of design of radiation resistant silicon detectors. The choice to use ...p-type substrates to improve the charge collection efficiency involves an optimization of the strip isolation to interrupt the inversion layer between the n± implants, limiting the breakdown voltage. To this purpose, TCAD modeling and simulation schemes, already developed and validated at typical LHC fluences have to be adapted to take into account effects usually neglected at lower fluences. To better understand in a comprehensive framework, the complex and articulated phenomena related to bulk and surface radiation damage, measurements on test structures and sensors, as well as TCAD simulations related to bulk, surface and interface effects, have been carried out. In particular, we have studied the properties of the SiO 2 layer and of the Si-SiO 2 interface, using MOS capacitors and gate-controlled diodes (gated diodes) manufactured by different vendors on a high-resistivity p-type silicon before and after irradiation with X-rays in the range from 50 krad to 10 Mrad. In this paper, we present the results of the experimental characterizations as well as the simulation findings, in order to analyze the effects of the interface traps on the strip isolation. This analysis helps us to validate the model and to identify the most sensitive technological and design parameters to be optimized for the design of advanced 2-D and 3-D silicon radiation detectors.
The structural, optical and electrical properties of sputtered cuprous oxide thin films have been optimized through post-deposition thermal treatments. Moreover we have studied the effects of ...nitrogen doping introduced by ion implantation followed by the optimized oxidant thermal annealing. Three concentrations have been used, 0.6N%, 1.2N%, and 2.5N%. Along with the preservation of the Cu2O phase, a slight optical band gap narrowing and a significant conductivity enhancement has been observed with respect to the undoped samples. These results can be justified by the absence of further oxygen vacancies promoted by dopant introduction and by the substitution of O atoms by N ones. This lattice configuration has been guaranteed by the post implantation annealing in oxidant atmosphere. The used doping technique represents an original out-of-equilibrium approach toward the formation of low-resistivity contacts on Cu2O films for photovoltaic applications.
•High crystallinity and conductivity of Cu2O obtained by annealing optimization•Ion implantation has been chosen to introduce a wide range of nitrogen doses.•We study the influence of nitrogen doping on the physical properties of Cu2O.•Nitrogen doping induces a small narrowing of band gap and an increase of conductivity.•The increase of conductivity is also caused by the interdiction of oxygen vacancies.
Virtual data center (VDC) solutions provide an environment that is able to quickly scale up, and where virtual machines and network resources can be quickly added on-demand through self-service ...procedures. VDC providers must support multiple simultaneous tenants with isolated networks on the same physical substrate. The provider must make efficient use of its available physical resources while providing high-bandwidth and low-latency connections to tenants with a variety of VDC configurations. This paper utilizes state-of-the-art optical network elements to provide high-bandwidth optical interconnections and develop a VDC architecture to slice the network and the compute resources dynamically, to efficiently divide the physical network between tenants. We present a data center virtualization architecture with a softwaredefined networking controlled all-optical data plane combining optical circuit switching and a time-shared optical network. Developed network orchestration dynamically translates and provisions VDCs requests onto the optical physical layer. The experimental results show the provisioned bandwidth can be varied by adjusting the number of time slots allocated in the time-division multiplexing (TDM) network. These results lead to recommendations for provisioning TDM connections with different performance characteristics. Moreover, application-level optical switch reconfiguration time is also evaluated to fully understand the impact on application performance in VDC provision. The experimental demonstration confirmed that the developed VDC approach introduces negligible delay and complexity on the network side.
The vertex detectors for the future hadronic colliders will operate under proton fluencies above 1016 p/cm2. Crystalline Silicon detector technology, up to now, has kept the pace of the increasing ...fluencies in the LHC era and it is still the prevalent vertex detector material for the present and for the immediate future. Looking ahead in time, an alternative solution for such a detector has to be found because for the future there is no guarantee that Crystalline Silicon will hold this challenge. For this reason the development of hydrogenated amorphous silicon vertex detectors based on 3D-technology have been proposed and the technological solutions in order to build these detectors are described in this paper.
Radiation tolerance of diamond detectors Bäni, L; Artuso, M; Bachmair, F ...
Journal of physics. Conference series,
11/2022, Letnik:
2374, Številka:
1
Journal Article
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Odprti dostop
Diamond is used as detector material in high energy physics experiments due to its inherent radiation tolerance. The RD42 collaboration has measured the radiation tolerance of chemical vapour ...deposition (CVD) diamond against proton, pion, and neutron irradiation. Results of this study are summarized in this article. The radiation tolerance of diamond detectors can be further enhanced by using a 3D electrode geometry. We present preliminary results of a poly-crystalline CVD (pCVD) diamond detector with a 3D electrode geometry after irradiation and compare to planar devices of roughly the same thickness.
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