Sabina Ronchin

Bio: Sabina Ronchin is an academic researcher from fondazione bruno kessler. The author has contributed to research in topics: Silicon & Semiconductor detector. The author has an hindex of 16, co-authored 103 publications receiving 1046 citations.

Development of 3D detectors featuring columnar electrodes of the same doping type

Abstract: We present a new 3D detector architecture aimed at simplifying the manufacturing process making it more suitable for high volume production. In particular, the proposed device features electrodes of one doping type only, e.g., n + columns in a p-type substrate. We report on TCAD simulation results providing deep insight into the static and dynamic behavior of this detector, highlighting its advantages and potential drawbacks. The fabrication process we intend to use is also described along with results from the morphological characterization of the most critical technological steps.

Double-Sided, Double-Type-Column 3-D Detectors: Design, Fabrication, and Technology Evaluation

Abstract: We report on the latest results from the development of 3-D silicon radiation detectors at Fondazione Bruno Kessler of Trento (FBK), Italy (formerly ITC-IRST). Building on the results obtained from previous devices (3-D Single-Type-Column), a new detector concept has been defined, namely 3-D-DDTC (Double-sided Double-Type Column), which involves columnar electrodes of both doping types, etched from alternate wafer sides, stopping a short distance (d) from the opposite surface. Simulations prove that, if d is kept small with respect to the wafer thickness, this approach can yield charge collection properties comparable to those of standard 3-D detectors, with the advantage of a simpler fabrication process. Two wafer layouts have been designed with reference to this technology, and two fabrication runs have been performed. Technological and design aspects are reported in this paper, along with simulation results and initial results from the characterization of detectors and test structures belonging to the first 3-D-DDTC batch.

Radiation-hard semiconductor detectors for SuperLHC

Abstract: An option of increasing the luminosity of the Large Hadron Collider (LHC) at CERN to 1035 cm−2 s−1 has been envisaged to extend the physics reach of the machine. An efficient tracking down to a few centimetres from the interaction point will be required to exploit the physics potential of the upgraded LHC. As a consequence, the semiconductor detectors close to the interaction region will receive severe doses of fast hadron irradiation and the inner tracker detectors will need to survive fast hadron fluences of up to above 1016 cm−2. The CERN-RD50 project “Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders” has been established in 2002 to explore detector materials and technologies that will allow to operate devices up to, or beyond, this limit. The strategies followed by RD50 to enhance the radiation tolerance include the development of new or defect engineered detector materials (SiC, GaN, Czochralski and epitaxial silicon, oxygen enriched Float Zone silicon), the improvement of present detector designs and the understanding of the microscopic defects causing the degradation of the irradiated detectors. The latest advancements within the RD50 collaboration on radiation hard semiconductor detectors will be reviewed and discussed in this work.

Fabrication of Novel MEMS Microgrippers by Deep Reactive Ion Etching With Metal Hard Mask

Abstract: The fabrication of a novel class of microgrippers is demonstrated by means of bulk microelectromechanical systems (MEMS) technology using silicon on insulator wafer substrates and deep reactive ion etching. Hard masking is implemented to maximize the selectivity of the bulk etching using sputtered aluminum and aluminum–titanium thin films. The micro-roughness problem related to the use of metal mask is addressed by testing different mask combinations and etching parameters. The O2 flow, SF6 pressure, wafer temperature, and bias power are examined, and the effect of each parameter on micro-masking is assessed. Sidewall damage associated with the use of a metal mask is eliminated by interposing a dielectric layer between silicon substrate and metal mask. Dedicated comb-drive anchors are implemented to etch safely both silicon sides down to the buried oxide, and to preserve the wafer integrity until the final wet release of the completed structures. A first set of complete devices is realized and tested under electrical actuation. [2017-0039]

Development of a new generation of 3D pixel sensors for HL-LHC

Abstract: This paper covers the main technological and design aspects relevant to the development of a new generation of thin 3D pixel sensors with small pixel size aimed at the High-Luminosity LHC upgrades.

The ATLAS Experiment at the CERN Large Hadron Collider

Abstract: This paper describes the ATLAS experiment as installed in i ts experimental cavern at point 1 at CERN. It also presents a brief overview of the expec ted performance of the detector.

Production and integration of the ATLAS Insertable B-Layer

Abstract: During the shutdown of the CERN Large Hadron Collider in 2013-2014, an additional pixel layer was installed between the existing Pixel detector of the ATLAS experiment and a new, smaller radius beam pipe. The motivation for this new pixel layer, the Insertable B-Layer (IBL), was to maintain or improve the robustness and performance of the ATLAS tracking system, given the higher instantaneous and integrated luminosities realised following the shutdown. Because of the extreme radiation and collision rate environment, several new radiation-tolerant sensor and electronic technologies were utilised for this layer. This paper reports on the IBL construction and integration prior to its operation in the ATLAS detector.

Silicon carbide and its use as a radiation detector material

Abstract: We present a comprehensive review of the properties of the epitaxial 4H silicon carbide polytype (4H–SiC). Particular emphasis is placed on those aspects of this material related to room, high-temperature and harsh environment ionizing radiation detector operation. A review of the characterization methods and electrical contacting issues and how these are related to detector performance is presented. The most recent data on charge transport parameters across the Schottky barrier and how these are related to radiation spectrometer performance are presented. Experimental results on pixel detectors having equivalent noise energies of 144 eV FWHM (7.8 electrons rms) and 196 eV FWHM at +27 °C and +100 °C, respectively, are reported. Results of studying the radiation resistance of 4H–SiC are analysed. The data on the ionization energies, capture cross section, deep-level centre concentrations and their plausible structures formed in SiC as a result of irradiation with various particles are reviewed. The emphasis is placed on the study of the 1 MeV neutron irradiation, since these thermal particles seem to play the main role in the detector degradation. An accurate electrical characterization of the induced deep-level centres by means of PICTS technique has allowed one to identify which play the main role in the detector degradation.

Displacement Damage Effects in Irradiated Semiconductor Devices

Abstract: A review of radiation-induced displacement damage effects in semiconductor devices is presented, with emphasis placed on silicon technology. The history of displacement damage studies is summarized, and damage production mechanisms are discussed. Properties of defect clusters and isolated defects are addressed. Displacement damage effects in materials and devices are considered, including effects produced in silicon particle detectors, visible imaging arrays, and solar cells. Additional topics examined include NIEL scaling, carrier concentration changes, random telegraph signals, radiation hardness assurance, and simulation methods for displacement damage. Areas needing further study are noted.