Perovskite Polycrystalline Direct Radiation Detectors
Creators: name: Alghamdi, Suad Saeed M
Publisher: name: University of Surrey
Year: 2024
Subjects: radiation senstivity
perovksite
crystal growith
radiation detectors
Semiconductors

description: This thesis discusses the interaction of radiation with matter and the characterisation of advancedradiation detectors, focusing on the use of perovskite materials, specifically FAPbBr3 polycrystalline,in the field of X-ray detection. The research begins with a comprehensive review of the mainprinciples of radiation interaction with matter, including X-ray interactions such as Compton scattering,the photoelectric effect, and Rayleigh scattering. Basic concepts in radiation dosimetry andcharge carrier transport in semiconductor materials are also discussed, providing a foundation forunderstanding the behaviour of semiconductor radiation detectors. The properties and synthesisof perovskite materials are examined, discussing various methods of synthesising polycrystallineperovskite materials, such as inverse temperature crystallisation, low-temperature crystallisation,and heating-assisted solvent evaporation. Different techniques to enhance perovskite detector performance,such as hot pressing, surface passivation, and mixing 2D and 3D perovskite structures,are also discussed. The experimental methodology for fabricating and characterising FAPbBr3detectors is detailed, including FAPbBr3 synthesis, grinding methods to create powder, device fabrication,and gold contact deposition. Different characterisation techniques were employed, suchas photoluminescence spectroscopy, scanning electron microscopy, X-ray diffraction, and atomicforce microscopy, to analyse FAPbBr3 properties and device performance. Significant findings onoptimising the performance of FAPbBr3 pellets in the radiation detection field are presented, focusingon the impact of different pressures, grinding methods, environmental impact, annealing, andhot-pressing impact. Key performance evaluations include electrical resistivity and behaviour, photoluminescenceproperties, and X-ray sensitivity. The impact of lead acetate addition to FAPbBr3during fabrication and the application of guard rings to enhance device performance are also explored.The thesis concludes with a discussion of the key findings, limitations, and potential futurestudies to develop and improve the performance of radiation detection. The project demonstratesthe promising potential of FAPbBr3 devices for advanced X-ray detection applications, highlightingareas of further study and research to optimise the performance of high-performance radiationdetectors. After conducting the research, it has been found that the ideal thickness for FAPbBr3pellets for radiation detection is 1 mm. A pressing time of 5 minutes and applying higher pressuresresulted in better outcomes. Annealing significantly improved the overall detector quality, enhancingsensitivity. Additionally, including lead acetate helped decrease dark current, further optimisingthe device’s performance for efficient radiation detection. These findings provide a clear pathwayfor creating high-performance FAPbBr3-based radiation detectors.