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In this work, we have investigated the performance of a 4H–SiC radiation sensor in the temperature range from 25 °C to 450 °C to explore its compatibility as detector of fast ion losses in plasma diagnostic of future nuclear fusion reactors. To simulate the escape of fusion-born alpha particles in D-T (deuterium-tritium) fusion plasmas, spectroscopic measurements were carried out in a vacuum chamber by irradiating the detector with a 3.5 MeV alpha beam from a Tandem accelerator. The detector was found to have an energy resolution ≤2% over the entire temperature range analyzed. Relevantly, the excellent spectrometric capabilities of the device have allowed us to calculate from experimental data, with unprecedented accuracy, the average energy required to create a single electron-hole pair in 4H–SiC as a function of temperature.

Pixelated LGADs have been established as the baseline technology for timing detectors for the High Granularity Timing Detector (HGTD) and the Endcap Timing Layer (ETL) of the ATLAS and CMS experiments, respectively. The drawback of segmenting an LGAD is the non-gain area present between pixels and the consequent reduction in the fill factor. To overcome this issue, the inverse LGAD (iLGAD) technology has been proposed by IMB-CNM to enhance the fill factor and provide excellent tracking capabilities. In this work, we explore the use of iLGAD sensors for surface damage irradiation by developing a new generation of iLGADs, the periphery of which is optimized to improve the performance of irradiated sensors. The fabricated iLGAD sensors exhibit good electrical performances before and after X-ray irradiation.

In the last few years, Low Gain Avalanche Detectors (LGAD) have demonstrated their outstanding performance when detecting high-energy charged particles. However, due to the difference in the multiplication mechanism for holes and electrons, the detection performance for low penetrating particles (e.g low-energy protons or soft x-rays) is significantly reduced. A novel design of an LGAD detector, the NLGAD, was designed and fabricated at CNM to overcome this drawback. A qualitative description of the NLGAD concept is presented in this work, along with gain response measurements of the first prototypes under visible light of 660 nm and 15 keV x-rays. Additionally, a review of the gain response under visible light of 404 nm and IR light of 1064 nm, previously studied, is also evaluated in this work. The results demonstrate that the NLGAD concept has the potential to detect low penetrating particles.

Silicon carbide (SiC) is a wide bandgap semiconductor with outstanding properties that make it especially appropriate for radiation monitoring in radiation harsh environments and for elevated temperature operation. In this work, radiation effects in electron-, neutron-, and proton-irradiated 4H-SiC p-n junction diodes are investigated by means of electrical characterization, including current-voltage characteristics measured at different temperatures ranging from -50 °C to +200°C. Moreover, the stability of the radiation-induced effects is evaluated through a series of low-temperature treatments (up to 400 °C). Interestingly for applications, partial recovery of diode rectification functionality is observed for electron-irradiated devices. Furthermore, partial recuperation of detectors' charge collection efficiency (CCE) is registered on either electron-, neutron-, or proton-irradiated devices. Remarkably, it is observed that the limited conduction registered for highly irradiated SiC detectors allows their operation in forward bias conditions. In fact, while providing some lower CCE, they show better energy resolution than in conventional reverse bias operation. Advantages of using SiC devices in alpha particle detection in harsh environments, as well as simplification of current Si experiments, can be envisaged.

Due to their low leakage current, low noise levels, high thermal conductivity, and potential radiation hardness, SiC devices offer various advantages over Si devices in certain applications. As a result, they are being considered for operation in harsh environments, such as plasma diagnostic systems in future nuclear fusion reactors or in high energy physics applications. We report on relevant results of the GRACE project, which seeks to deliver a new generation of SiC sensors with graphene-enhanced contacts. Such devices are aimed to be radiation-hard and functional at high temperatures. The work presented in this paper focuses on the optimisation of the electrical contacts, along with the electrical characterisation and radiation-tolerance assessment of the first sensor prototypes produced.

[EN] The low-penetrating particles low gain avalanche detector comprises a multi-layered structure and receives particles from a radiation source (13). It consists of a thin entry region that receives the particles from the radiation source (13); a low-penetrating particles detection region, with a p++ shallow field stop (1), positioned beneath the entry region, and a p absorption layer (3), positioned beneath the p++ shallow field stop (1), and an n multiplication layer (4); and a high-penetrating particles detection region positioned beneath the n multiplication layer (4), consisting of a n-- silicon substrate (5). Due to the chosen doping polarities, the primary electrons (created by the particles from the radiation source (13)) drift away from the entry region. That way, signals from low-penetrating particles or radiation experience amplification, while the noise is kept similar to a conventional PIN structure, thus increasing the signal-to-noise ratio., [FR] Le détecteur d'avalanche à faible gain à particules à faible pénétration comprend une structure multicouche et reçoit des particules d'une source de rayonnement (13). Il est constitué d'une région d'entrée mince qui reçoit les particules de la source de rayonnement (13) ; d'une région de détection de particules à faible pénétration, ayant un diaphragme de champ peu profond p++ (1), positionnée sous la région d'entrée, et d'une couche d'absorption de type p (3), positionnée sous le diaphragme de champ peu profond p++ (1), et d'une couche de multiplication n (4) ; et d'une région de détection de particules à pénétration élevée positionnée sous la couche de multiplication n (4), constituée d'un substrat de silicium n-- (5). En raison des polarités de dopage choisies, les électrons primaires (créés par les particules provenant de la source de rayonnement (13)) dérivent de la région d'entrée. De cette manière, des signaux provenant de particules à faible pénétration ou d'une amplification d'expérience de rayonnement, tandis que le bruit reste similaire à une structure PIN classique, augmentent le rapport signal sur bruit.

In this contribution we will present the first measurements on LGADs corresponding to our CNM’s second engineering run based on 6-inch, 50µm active layer thick, epitaxial wafers (6LG3 technology). Some of the wafers were carbon enriched using two different doses and one implantation energy. For the gain layer, samples were fabricated using different boron doses and diffusion times and one implantation energy. Measurements, simulations and analysis of breakdown and depletion voltages were carried out on these LGADs. The presented results will serve as a stepping stone to select the best technological parameters for the gain and carbon layer definition in the upcoming ATLAS-CMS common run, based on 6-inch Si-Si wafers (6LG2 technology).

Due to their low leakage current, low noise levels, high thermal conductivity, and potential radiation hardness, SiC devices offer various advantages over Si devices in certain applications. As a result, they are being considered for operation in harsh environments, such as plasma diagnostic systems in future nuclear fusion reactors or in high energy physics applications. We report on relevant results of the GRACE project, which seeks to deliver a new generation of SiC sensors with graphene-enhanced contacts. Such devices are aimed to be radiation-hard and functional at high temperatures. The work presented in this paper focuses on the optimisation of the electrical contacts, along with the electrical characterisation and radiation-tolerance assessment of the first sensor prototypes produced.

Gain suppression induced by excess carriers in Low Gain Avalanche Detectors (LGADs) has been investigated using 3 MeV protons in a nuclear microprobe. In order to modify the ionization density inside the detector, Ion Beam Induced Current (IBIC) measurements were performed at different proton beam incidence angles between 0° and 85°. The experimental results have been analyzed as a function of the ionization density projected on the multiplication layer, finding that the increase of ionization density leads to greater gain suppression. For bias voltages close to the gain onset value, this decrease in gain results into a significant distortion of the transient current waveforms measured by the Time-Resolved IBIC (TRIBIC) technique due to a deficit in the secondary holes component. For angles of incidence such that the Bragg peak falls within the sensitive volume of the detector, the formation of microplasmas modifies the behavior of the gain curves, producing an abrupt decrease in gain as the angle increases.

A radiation tolerance study of planar diodes fabricated on a SiC substrate will be presented. TPA-TCT was used to characterize the samples. The measurement campaign was carried out at the laser facility of the EHU-UPV university.