Useche Parra, JuanS., Dr. (University of Freiburg, Freiburg Material Research Center, Freiburg, Germany); Yang, Ge, (North Carolina State University, Department of Nuclear Engineering, Raleigh, USA)
Shortcut:
RTSD-06
Date:
Wednesday, 11 November, 2026, 11:30 -
13:00
Location:
ANDALUCÍA II & III
Session type:
RTSD Session
Contents
Click on an contribution to preview the abstract content.
The underlined authors are the presenters. The authors in bold are the main authors.
11:30
RTSD-06-01
Influence of the Active Layer Thickness on the Performance of Metal-Halide-Perovskite Thin Films for X-ray Detectors (#1972)
M. Girolami1, F. Matteocci2, M. Bagheri Khorasgani2, Z. Skafi2, A. Ranieri4, S. Pettinato3, S. Salvatori3, T. M. Brown2, A. Di Carlo2, D. M. Trucchi1
1 CNR - Consiglio Nazionale delle Ricerche, DiaTHEMA Lab, ISM - Istituto di Struttura della Materia, Montelibretti, Italy 2 University of Rome Tor Vergata, C.H.O.S.E. (Centre for Hybrid and Organic Solar Energy), Department of Electronic Engineering, Roma, Italy 3 Università degli Studi Niccolò Cusano, Faculty of Engineering, Roma, Italy 4 CNR - Consiglio Nazionale delle Ricerche, IC - Istituto di Cristallografia, Montelibretti, Italy
Abstract
The performance under X-rays (with energies up to 40 keV) of self-powered detectors with a submicrometric metal-halide-perovskite (FAPbBr3) active layer was systematically investigated as a function of the FAPbBr3 film thickness, ranging from 180 to 840 nm. Results show that an intermediate thickness of 710 nm represents the best trade-off among sensitivity (up to 571.07 μC Gy-1 cm-2), limit of detection (down to 39.55 nGy s-1), linearity with the dose-rate, and stability over time (signal fluctuations <1% within 1 h of continuous irradiation).Very significantly, it is here shown that, in the case of submicrometric FAPbBr3 film-based X-ray detectors, a better performance is not necessarily connected to a larger thickness; the benefits of a better X-ray absorption are indeed nullified by a drastic decrease of the photoconductive gain, due to increased interface charge accumulation and enhanced recombination.
Optimization of FAPbBr3 Single Crystals for Photon Counting Radiation Detection (#2520)
J. Jayarathne1, A. Dickinson1, J. Green1, M. Zahid1, C. Crean2, S. Perera1, P. Sellin1
1 University of Surrey, School of Mathematics and Physics, Guildford, United Kingdom 2 University of Surrey, School of Chemistry and Chemical Engineering, Guildford, United Kingdom
Abstract
The organic hybrid perovskite FAPbBr3 shows great potential as a radiation detector, particularly due to its synthesis using cost-effective room-temperature solution-based growth processes. In this paper we report on recent improvements in the quality of solution-grown FAPbBr3 single crystals using a sulfonic zwitterionic ligand 3-(Decyldimethylammonio)propanesulfonate inner salt (DPSI). By optimizing the growth process we have produced X-ray and gamma ray detectors that show excellent charge transport properties, with a high hole mobility of 190 cm2/Vs and a high hole mobility-lifetime (µτ) product of 2.7 x 10-3 cm2/V, combined with a low dark current of 2.9 nA cm-2 operating at a field strength of 1000 V/cm. These FAPbBr3 detectors show well-resolved low energy gamma peaks from 241Am, with an energy resolution of 25.6% FWHM at 59.5 keV.
Keywords: Lead Halide Perovskite, Radiation Detector, Gamma spectroscopy
12:00
RTSD-06-03
Transient Currents in 4H–SiC Radiation Sensors with Graphene Electrodes (#2924)
E. Belas1, M. Betušiak1, R. Grill1, P. Praus1, J. Kunc1, R. Nag2, K. C. Mandal2
1 Charles University, Faculty of Mathematics and Physics, Institute of Physics, Prague 2, Czech Republic 2 University of South Carolina, Department of Electrical Engineering, Columbia, United States of America
Abstract
We investigate charge transport in both 4H–SiC semiinsulating bulk graphene/semiinSiC/Ni sensor and epitaxial graphene/epiSiC/subsSiC/Ni Schottky barrier diode structure. Using the laser-induced Transient Current Technique (L–TCT), combined with alpha spectroscopy and I–V characterization, we investigate charge transport across either the bulk or epilayer and adjacent substrate. Our results reveal rapid space charge formation at all structures, even under pulsed bias, attributed to electron depletion. It is shown that in contrast to metallic electrodes showing fast damped oscillations, the graphene electrodes lead to significantly slower non-oscillating exponential-like current waveforms. Observed phenomena were successfully described by theoretical model based on surface plasmons in both sensors. These findings highlight the importance of the transient current technique for the investigation of SiC sensors.
Acknowledgment
This project is co-financed from the state budget by the Technology agency of the Czech Republic under the TACR 13 SIGMA DC5 Programme TQ28000004.
L. Pan1, Q.V. Phan3, M. Unal3, S. Lee1, D.Y. Chung3, J. W. Cates1, O. Aggarwal2, M. Turqueti2, G. Ariño-Estrada4, M. G. Kanatzidis3, J. Caravaca1
1 Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, California, United States of America 2 Lawrence Berkeley National Laboratory, Engineering Division, Berkeley, California, United States of America 3 Argonne National Laboratory, Materials Science Division, Lemont, Illinois, United States of America 4 University of California Davis, Department of Biomedical Engineering, Davis, California, United States of America
Abstract
Perovskite CsPbBr3 is promising as next-generation room temperature semiconductor gamma-ray detector. While remarkable energy resolution has been achieved (e.g., 1% at 662 keV) for CsPbBr3, its timing resolution is expected to be limited by the charge transport process as semiconductor (as a reference, timing resolution is several ns or worse for semiconductor CdZnTe or TlBr). Here, we report sub-nanosecond time resolution utilizing the prompt Cherenkov emission from the CsPbBr3 as fast timing signal while maintaining its good energy resolution. We demonstrate successful simultaneous readout of semiconductor charge induction signal and SiPM Cherenkov light signal. By associating the Cherenkov light signal with the charge signal, good energy resolution of ~3% at 511 keV and sub-ns coincidence timing resolution of ~ 583 ps with 22Na gamma-ray source were achieved simultaneously. We expect further improvement of time and energy resolution with a high-frequency SiPM read-out PCB and a dedicated charge-readout PCB with integrated high-performance pre-amplifiers. Built upon the high energy resolution and the ability to provide spatial information of gamma-ray interaction, the sub-ns fast timing capability would markedly broaden the applications of CsPbBr3 gamma-ray detectors that are projected to have low cost compare to CdZnTe.
AcknowledgmentThis research was supported by the DOE Laboratory Directed Research and Development Program through Lawrence Berkeley National Laboratory.
References [1] G. Ariño-Estrada et al., "First Cerenkov charge-induction (CCI) TlBr detector for TOF-PET and proton range verification," Physics in Medicine & Biology, vol. 64, no. 17, p. 175001, 2019. [2] G. Ariño-Estrada et al., "Towards time-of-flight PET with a semiconductor detector," Physics in Medicine & Biology, vol. 63, no. 4, p. 04LT01, 2018. [3] G. Ariño-Estrada et al., "Study of Čerenkov light emission in the semiconductors TlBr and TlCl for TOF-PET," IEEE transactions on radiation and plasma medical sciences, vol. 5, no. 5, pp. 630-637, 2020. [4] K. Hitomi, C. Kim, M. Nogami, K. Shimazoe, and H. Takahashi, "Characterization of coincidence time resolutions of TlBr x Cl1− x crystals as Cherenkov radiators," Japanese Journal of Applied Physics, vol. 62, no. 8, p. 081001, 2023. [5] G. Terragni et al., "Time resolution studies of thallium based Cherenkov semiconductors," Frontiers in Physics, vol. 10, p. 93, 2022. [6] K. Hitomi et al., "Timing performance of TlBr detectors," IEEE Transactions on Nuclear Science, vol. 60, no. 4, pp. 2883-2887, 2013. [7] N. Shen et al., "Single photon γ-ray imaging with high energy and spatial resolution perovskite semiconductor for nuclear medicine," Nature Communications, vol. 16, no. 1, p. 8113, 2025. [8] Y. He, I. Hadar, and M. G. Kanatzidis, "Detecting ionizing radiation using halide perovskite semiconductors processed through solution and alternative methods," Nature Photonics, vol. 16, no. 1, pp. 14-26, 2022. [9] L. Pan et al., "Geant4 Simulation of Cherenkov Photons in Perovskite CsPbBr3 Gamma-Ray Detectors," IEEE Transactions on Radiation and Plasma Medical Sciences, 2025.
Unraveling Atmosphere-Dependent Trap-Mediated X-Ray Detection in Organic Field-Effect Transistors (#2896)
G. Napolitano1, I. Fratelli1, 2, C. Martínez-Domingo3, M. Makala4, L. Fijahi5, I. Kymissis2, O. Jurchescu4, B. Fraboni1, 6, M. Mas-Torrent5, L. Basiricò1, 6
1 University of Bologna, Department of Physics and Astronomy, Bologna, Italy 2 Columbia University, Department of Electrical Engineering, New York, New York, United States of America 3 Institute of Microelectronics of Barcelona, IMB-CNM-CSIC, Bellaterra, Spain 4 Wake Forest University, Deparment of Physics and Center for Functional Materials, Winston-Salem, North Carolina, United States of America 5 Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Bellaterra, Spain 6 INFN-BO, Bologna, Italy
Abstract
Organic field-effect transistors are promising candidates for ionizing radiation dosimetry due to their low-cost fabrication, large-area processability, and tissue-equivalent composition. However, their response is strongly affected by environmental species, such as oxygen and moisture, which can induce charge traps and compromise detector stability. Here, we investigate the role of Parylene-C encapsulation in TMTES:PS-based OFET X-ray detectors. The encapsulation layer preserves the pristine electrical performance while significantly improving shelf stability. Under X-ray irradiation, uncoated devices exhibit air-dependent transient dynamics, with recovery in air and integrative behavior in vacuum. In contrast, Parylene-C-coated devices show stable and cumulative response independently of the surrounding environment, indicating that encapsulation suppresses air-induced trap formation. Trap density of states analysis supports this interpretation, revealing additional shallow trap states only in uncoated devices irradiated in air. Encapsulated OFETs further display a dose-dependent threshold-voltage shift, with a maximum sensitivity of 0.109 ± 0.002 V Gy⁻¹ and long-lived retention of the absorbed dose information. These results demonstrate that Parylene-C encapsulation is not only an effective strategy to improve environmental stability, but also a key tool to control the radiation response of organic transistor-based dosimeters.
Acknowledgment
L.B. acknowledges INNOVARE project funded by Fondazione Compagnia di S. Paolo-CARIPLO-CDP grant “vEIColo – accompagnamento per la
valorizzazione della ricerca” Grant No. 2025.1624; I.F. has received funding from Horizon Europe under the Marie Skłodowska-Curie grant agreement No 101105245, “Hybrid detectors for medical radiation therapies – IDEATE”.
References [1] Basiricò, L., Ciavatti, A., & Fraboni, B. (2021). 'Solution‐Grown Organic and Perovskite X‐Ray Detectors: A New Paradigm for the Direct Detection of Ionizing Radiation.' Advanced Materials Technologies, 6.1: 2000475 [2] Fratelli, I., Basiricò, L., Ciavatti, A., Lamport, Z. A., Anthony, J. E., Kymissis, I., & Fraboni, B. (2023). Trap States Ruling Photoconductive Gain in Tissue‐Equivalent, Printed Organic X‐Ray Detectors. Advanced Materials Technologies, 8.3: 2200769. [3] Haneef, H. F., Zeidell, A. M., & Jurchescu, O. D. (2020). Charge carrier traps in organic semiconductors: a review on the underlying physics and impact on electronic devices. Journal of Materials Chemistry C, 8.3: 759-787. [4] Giglio, M. E., Colantoni, E., Fratelli, I., Martinez‐Domingo, C., Martinez‐Zaragoza, P., Napolitano, G., ... & Mas‐Torrent, M. (2025). Vertical Phase Separation in Blended Organic Semiconducting Films and Impact on Their Electrical and Direct X‐Ray Detection Properties. Advanced Electronic Materials, 11.17: 2400887. [5] McKeen, L. W. (2017). Film properties of plastics and elastomers. William Andrew. [6] Jong, W. L., Wong, J. H. D., Ung, N. M., Ng, K. H., Ho, G. F., Cutajar, D. L., & Rosenfeld, A. B. (2014). Characterization of MOSkin detector for in vivo skin dose measurement during megavoltage radiotherapy. Journal of applied clinical medical physics, 15.5: 120-132. [7] Bordoni, C., Ciavatti, A., Cortinhal, M., Pereira, M., Cramer, T., Barquinha, P., & Fraboni, B. (2024). Dielectric multilayers impact on radiation-induced charge accumulation in highly sensitive oxide field effect transistors. APL Materials, 12.3.
Keywords: Organic field-effect transitors, Personal Dosimetry, Parylene-C encapsulation
12:45
RTSD-06-06
Li- and B-Doped CsPbBr₃ Composites for Fast Radiation Scintillation Detection (#2944)
M. Boukhicha1, S. A. Reisbick1, C. Luca1, T. Thomas1
1 Brookhaven National Laboratory, Instrumentation, Upton, New York, United States of America
Abstract
Efficient and scalable scintillators are critical for applications in medical imaging, nuclear security, and environmental monitoring. Here, we investigate lithium-6 and boron-10 doped CsPbBr3 perovskite-polymer composites for dual-mode neutron and X-ray detection. A scalable ball-milling process was used to incorporate neutron-sensitive isotopes into CsPbBr3 nanocrystals embedded in PMMA and PDMS matrices. The resulting composites combine the neutron capture capabilities of lithium-6 and boron-10 with the favorable optical properties of CsPbBr3, including high light yield, emission near 520 nm, and sub-nanosecond decay times. HR-TEM analysis confirmed a homogeneous distribution of ~10 nm nanocrystals throughout the polymer matrix. Synchrotron-based measurements further demonstrated strong radioluminescence and fast scintillation response under X-ray excitation. Preliminary studies also indicate promising neutron and alpha-particle scintillation performance, highlighting the potential of these flexible and scalable composites for next-generation radiation detection technologies.
