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This contribution explores the potential of PFIB for the post-production circuit editing of custom ASICs. The reworking of integrated circuits with ion beam is an effective tool for testing design modifications rapidly, and in small-volume productions, it proves to be a valuable substitute for the microfabrication of chips with a revised layout, thus reducing the cost and lead time. In the case study in this work, the PFIB intervention resulted in the recovery of ~90% of defective channels in a multichannel ASIC design by disconnecting some parts of the internal circuit. This contribution describes several implemented optimization strategies and their statistical effectiveness. [ABSTRACT FROM AUTHOR]

An accurate flux measurement of low-energy charged particles trapped in the magnetosphere is necessary for space weather characterization and to study the coupling between the lithosphere and magnetosphere, which allows for the investigation of the correlations between seismic events and particle precipitation from Van Allen belts. In this work, the project of a CubeSat space spectrometer, the low-energy module (LEM), is shown. The detector will be able to perform an event-based measurement of the energy, arrival direction, and composition of low-energy charged particles down to 0.1 MeV. Moreover, thanks to a CdZnTe mini-calorimeter, the LEM spectrometer also allows for photon detection in the sub-MeV range, joining the quest for the investigation of the nature of gamma-ray bursts (GRBs) and terrestrial gamma-ray flashes (TGFs). The particle identification of the LEM relies on the Δ E − E technique performed by thin silicon detectors. This multipurpose spectrometer will fit within a 10 × 10 × 10 cm 3 CubeSat frame, and it will be constructed as a joint project between the University of Trento, FBK, and INFN-TIFPA. To fulfil the size and mass requirements, an innovative approach, based on active particle collimation, was designed for the LEM; this avoids the heavy/bulky passive collimators of previous space detectors. In this paper, we will present the LEM geometry, its detection concept, the results from the developed GEANT4 simulation, and some characterisations of a candidate silicon detector for the instrument payload. [ABSTRACT FROM AUTHOR]

An accurate flux measurement of low-energy charged particles trapped in the magnetosphere is necessary for space weather characterization and to study the coupling between the lithosphere and magnetosphere, which allows for the investigation of the correlations between seismic events and particle precipitation from Van Allen belts. In this work, the project of a CubeSat space spectrometer, the Low-Energy Module (LEM), is shown. The detector will be able to perform an event-based measurement of the energy, arrival direction, and composition of low-energy charged particles down to 0.1 MeV. Moreover, thanks to a CdZnTe mini-calorimeter, the LEM spectrometer also allows for photon detection in the sub-MeV range, joining the quest for the investigation of the nature of Gamma-ray bursts. The particle identification of the LEM relies on the Δ E − E technique performed by thin silicon detectors. This multipurpose spectrometer will fit within a 10 × 10 × 10 cm 3 CubeSat frame, and it will be constructed as a joint project between the University of Trento, FBK, and INFN-TIFPA. To fulfil the size and mass requirements, an innovative approach, based on active particle collimation, was designed for the LEM; this avoids the heavy/bulky passive collimators of previous space detectors. In this paper, we will present the LEM geometry, its detection concept, and the results from the developed GEANT4 simulation. [ABSTRACT FROM AUTHOR]

The ORION chipset, a full-custom multichip readout and processing electronics for the X- $\gamma $ -ray imaging spectrometer (XGIS) on-board the transient high-energy sky and early universe surveyor (THESEUS) space mission, is presented. The XGIS detection plane is arranged in a matrix of 10 $\times $ 10 detection modules, each one composed of 64 CsI(Tl) scintillation bars (4.5 mm $\times $ 4.5 mm $\times $ 30 mm) optically coupled at the top and bottom ends to two 8 $\times $ 8 monolithic silicon drift detector (SDD) matrices. The top SDD, exposed to the X-ray entrance window, performs the double function of low-energy X-ray detection as well as scintillator’s readout, together with the bottom SDD, providing detection and spectroscopic energy range from 2 keV up to 20 MeV. The need to achieve a high-energy resolution, as well as a high sensitive area on the detection plane, led to the development of a chipset organized to have a minimum-area analog readout chip placed in close proximity of the SDD (ORION-FE) and a mixed-signal back-end (ORION-BE) placed a few centimeters further on the back-end board for the additional signal processing and digitization. The multichip readout electronics integrates two dedicated analog processors for low-energy photons up to 30 keV (X-processor) and high-energy photons up to 5 MeV ($\gamma $ -processor), allowing a spectroscopy-grade resolution in the 4 decades energy band (2 keV–20 MeV) of the XGIS, with a simulated power consumption of 1.55 mW/pixel. The ORION prototype was bonded to two ~25 mm2 SDDs, and extensively characterized in terms of pulse shaping, pulse discrimination, and stretching functionality, as well as linearity, dynamic range, and spectroscopic resolution. An optimum equivalent noise charge (ENC) at −20 °C of 24.3 el. r.m.s. on the X-channel [212 eV full-width at half-maximum (FWHM) on Si], and 39.6 el. r.m.s. on the $\gamma $ -channel [3.7 keV FWHM on CsI(Tl)] has been recorded. [ABSTRACT FROM AUTHOR]

Precious metal catalyst has been prepared by conventional wet impregnation method followed by precipitation and reduction with hydrogen finally passivated with water in air. The magnetically recoverable catalyst has been prepared starting from a stoichiometric Fe3O4 and ZrO2-Fe3O4 as supports prepared following a sequential precipitation procedure. Precious metal catalysts supported on carbon, alumina, magnetite and zirconia-magnetite nanocomposite has been used in the reduction of nitrobenzenes and acetophenone by using sodium and potassium formate as reducing agent in the presence and in absence of an aqueous phase. In addition, the same catalysts has been tested in CO2 and NaHCO3 hydrogenation, for verifying their potentiality in the CO2 as hydrogen carrier for hydrogenation processes. [ABSTRACT FROM AUTHOR]

The stability and the evolution of electrical properties of high concentration arsenic ultra-shallow junctions in silicon have been studied with regard to their effect on the evolution of point defects. The activation of 2 keV 1 × 1015 cm-2 As implants was performed using millisecond sub-melt laser annealing at two different temperatures, 1100 and 1300 °C. The electrical deactivation upon subsequent thermal treatment at 700 °C was indirectly monitored through the diffusion of five 10 nm-wide boron layers aimed to detect the injection of self-interstitials coming from dopant clustering. Thermal treatments were repeated on samples implanted with Ge at condition similar to the As ones. The comparison helped to discriminate between interstitials coming from lattice damage evolution and dopant clustering. The results show the relevance of the laser annealing temperature in order to ensure junction stability in terms of active carrier concentration and junction depth. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The evolution of very high dose arsenic implants in silicon formed by plasma immersion ion implantation and deposition (PIIID) using a non-pulsed plasma source was studied over a time period of more than one year. The study focused on the effect of arsenolite micro-crystal formation, enhanced oxidation, and the significant As dose loss from as implanted samples at room temperature. The study was carried out combining analytical evidence from SIMS, XPS, INAA, SEM, and optical microscopy suggesting a two stage process of As dose loss, the first implying arsenolite crystal growth and the second an out-diffusion. In fact, comparison of samples fabricated using different PIIID parameters showed that crystal growth seems not to be the only process responsible for dose loss. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Spontaneous growth of arsenolite micro-crystals at room temperature after high fluence, low energy arsenic trihydride implantation in silicon was observed on the wafer surface after exposure to air. The crystals have been identified unambiguously by x-ray absorption and fluorescence spectroscopy. Thermal treatment easily sublimates the crystals at temperatures as low as 200 °C without any relevant in-diffusion of As into the substrate. The deposition of a thin As-rich layer under high fluence implantation conditions is suggested as possible precursor for crystal formation. The same layer can explain the anomalous retained dose increase often observed after annealing. [ABSTRACT FROM AUTHOR]