Article
Physics, Multidisciplinary
Martin Hoeferkamp, Alissa Howard, Gregor Kramberger, Sally Seidel, Josef Sorenson, Adam Yanez
Summary: Motivated by the need for fast timing detectors to withstand high ionizing doses, prototype low gain avalanche detectors (LGADs) were fabricated and studied. The effects of gamma rays on surface and interface states, as well as their contribution to acceptor removal through non-ionizing energy loss, were investigated.
FRONTIERS IN PHYSICS
(2022)
Article
Engineering, Biomedical
Andy LaBella, Wei Zhao, Amir H. Goldan
Summary: The use of amorphous selenium as the photoconductive material for TOF detectors shows promise in achieving higher time resolution and lower noise. The implementation of MWSD enables both avalanche gain and UTD charge sensing, improving the performance of TOF PET imaging.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Le Thanh Triet Ho, Atreyo Mukherjee, Dragica Vasileska, John Akis, Jann Stavro, Wei Zhao, Amir H. Goldan
Summary: To improve the performance of avalanche a-Se devices, understanding transport characteristics and controlling electrical hot spots are crucial. High-permittivity noninsulating material is needed to decrease the electric field at the electrode/HBL interface, preventing injection and crystallization of a-Se layer, avoiding early dielectric breakdown of the device.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Xin Li, Jian Chen, Jin Chen, Jiale He, Feilong Yu, Zengyue Zhao, Guanhai Li, Xiaoshuang Chen, Wei Lu
Summary: HgCdTe avalanche photodiode operating at high temperature in mid-infrared is crucial for ultra-weak light detection, but the increased dark current poses a significant challenge. In this study, a novel structure with a barrier in the gradient-doped absorption layer is proposed for high-temperature operation. This structure enables simultaneous dark current suppression and photoelectric gain enhancement by creating dual-avalanche areas and manipulating the band gap. Simulation results clarify the dynamic transportation mechanism and demonstrate the selective control of dark current without sacrificing the photoelectric gain at hot temperature.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Energy & Fuels
Huayun Ge, Xing Li, Chunlin Guo, Wei Luo, Rui Jia
Summary: It was found in this study that gallium-doped PERC cells had uneven resistivity, causing hot spots due to the avalanche breakdown of PN junctions. Significant hot spots were observed in the center of the tested cells, with an average resistivity of 0.4-0.5 ohm cm and nonuniformity greater than 30%, or an average resistivity of 0.5-0.6 ohm cm with nonuniformity greater than 40%.
Article
Materials Science, Multidisciplinary
Kevin Lauer, Katharina Peh, Stefan Krischok, Stephanie Reiss, Erik Hiller, Thomas Ortlepp
Summary: The acceptor removal phenomenon in low-gain avalanche detectors (LGAD) due to irradiation is investigated in this study. Boron, gallium, and indium implanted samples are examined before and after irradiation using various measurement techniques. The study evaluates different co-implantation species and their impact on reducing the acceptor removal phenomenon. It is found that low-dose fluorine and high-dose nitrogen co-implantation have the most significant beneficial effect in boron, while low-dose carbon and oxygen implantations are beneficial in gallium. In the case of indium, none of the co-implantation species show a beneficial effect. The depth profiles of boron concentration measured using secondary ion mass spectrometry (SIMS) before and after irradiation indicate no fast movement of boron at room temperature, suggesting that the B-Si-Si-i-defect explanation approach is more likely than the B-i-O-i-defect explanation approach.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2022)
Article
Instruments & Instrumentation
C. H. Li, X. Yang, J. J. Ge, T. Wang, X. X. Zheng, Y. J. Sun, Y. W. Liu
Summary: In this study, we reported the measurement results of LGAD sensors designed by the University of Science and Technology of China and fabricated by the Institute of Microelectronics of the Chinese Academy of Science. The sensors were irradiated with different doses and measured at low temperature. The results showed that these sensors have high collected charge and time resolution, meeting the design requirements of HGTD.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2022)
Article
Pharmacology & Pharmacy
Samuel O. Kyeremateng, Kristin Voges, Stefanie Dohrn, Ekaterina Sobich, Ute Lander, Stefan Weber, David Gessner, Rachel C. Evans, Matthias Degenhardt
Summary: This article describes the application of API-polymer phase diagrams in hot-melt extrusion (HME) technique and the development of an HME risk classification system (HCS) within AbbVie. The HCS categorizes API risks in the HME process and has been successfully applied to over 60 different APIs as a validated risk assessment and quality-by-design (QbD) tool. The classification system is based on the ability of the melt temperature to reach the API's thermodynamic solubility temperature and considers the thermal degradation regions and glass transition temperature-related dissolution kinetics limitations of API or polymer.
Article
Pharmacology & Pharmacy
Daniel Kramarczyk, Justyna Knapik-Kowalczuk, Mateusz Kurek, Witold Jamroz, Renata Jachowicz, Marian Paluch
Summary: In this study, the effectiveness of different polymers in creating posaconazole-based amorphous solid dispersions (ASDs) was examined. It was found that the use of an amorphous homopolymer-K30 was the most effective additive in improving the aqueous solubility and physical stability of the drug.
Article
Pharmacology & Pharmacy
Jiawei Han, Mengyuan Tang, Yang Yang, Wen Sun, Zhimin Yue, Yunran Zhang, Yijun Zhu, Xiaoqian Liu, Jue Wang
Summary: This review discusses the use of solid dispersion systems as an effective formulation strategy to enhance the performance of poorly water-soluble drugs. It provides a comprehensive understanding of SD classification and highlights the most popular amorphous solid dispersions. Furthermore, it proposes a systematic design strategy for satisfactory ASDs and explores the application of hot melt extrusion as a continuous manufacturing technique.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Naho Hanada, Kenjirou Higashi, Zhijing Zhao, Keisuke Ueda, Kunikazu Moribe
Summary: Ternary amorphous solid dispersions (ASDs) of probucol (PBC)/polymer/surfactant were successfully prepared by hot-melt extrusion method. The ASDs stabilized amorphous PBC mainly through hydrogen bonds formed between PBC and the polymer (PVP). Colloidal dispersions of amorphous PBC nanoparticles were obtained from the ASD using a weight ratio of 1:4:2 for PBC/PVP/P407, and the stability of the amorphous state was confirmed through storage experiments.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Engineering, Electrical & Electronic
Xingan Zhang, Yuxiao Liu, Yang Shao, Yongqiang Yan, Ru Yang, Kun Liang, Dejun Han
Summary: This article presents a 1-D position-sensitive LGAD (1-D PS-LGAD) based on dc coupling and a resistive charge division mechanism. The 1-D PS-LGAD features two cathodes and one anode, and two of them can be used to obtain 2-D position coordinates. The experimental results show that the 1-D PS-LGAD achieves high position and time resolution with an average position measurement error of 32.2 +/- 35.4 μm and a coincidence time resolution of 8.8 ps.
IEEE TRANSACTIONS ON NUCLEAR SCIENCE
(2023)
Article
Chemistry, Medicinal
Bhupendra Raj Giri, Jaewook Kwon, Anh Q. Vo, Ajinkya M. Bhagurkar, Suresh Bandari, Dong Wuk Kim
Summary: This study successfully enhanced the solubility, bioavailability, and stability of the antihypertensive drug Telmisartan through the fabrication of a pH-modulated solid dispersion using hot-melt extrusion technology. The optimized formulation showed significantly improved drug release profile, better stability, and superior pharmacokinetic parameters in rat studies.
Article
Engineering, Biomedical
Felix Ulrich-Pur, Thomas Bergauer, Alexander Burker, Albert Hirtl, Christian Irmler, Stefanie Kaser, Florian Pitters, Simon Rit
Summary: This study investigates the potential of a novel proton computed tomography (pCT) system based on low gain avalanche detectors (LGADs) to accurately determine the relative stopping power (RSP) distribution in ion beam therapy. Through Monte Carlo simulations, the researchers optimized the design parameters and achieved RSP accuracy below 0.6% using a dedicated calibration procedure for the time-of-flight (TOF) calorimeter. The study also identified design parameters with the strongest impact on RSP resolution and proposed strategies to further improve image quality. Overall, this comprehensive study provides valuable insights for future hardware developments and enhancing treatment planning quality in ion beam therapy.
PHYSICS IN MEDICINE AND BIOLOGY
(2022)
Article
Nutrition & Dietetics
Kenji Ishimoto, Yukiko Shimada, Akane Ohno, Shuichi Otani, Yukio Ago, Soya Maeda, Bangzhong Lin, Kazuto Nunomura, Nobumasa Hino, Masayuki Suzuki, Shinsaku Nakagawa
Summary: The study developed a safe and effective functional food material based on naringenin, which improved its solubility and absorption, showing potential for future applications.
FRONTIERS IN NUTRITION
(2022)
