20.500.12556/RUL-150014 Študija razdalje med blazinicami v silicijevih plazovnih detektorjih z nizko stopnjo pomnoževanja Studies of inter-pad distance in Low-Gain Avalanche Detectors V magistrskem delu je predstavljena študija efektivne razdalje med blazinicami prototipov plazovnih detektorjev z nizko stopnjo pomnoževanja za Visoko zrnati detektor časa na eksperimentu ATLAS. Preučili smo prototipe dveh proizvajalcev. Plazovni detektorji z nizko stopnjo pomnoževanja so bili izbrani za določanje časa preleta nabitih delcev na Visoko-luminoznostnem velikem hadronskem trkalniku zaradi izjemne časovne ločljivosti, ki jo zagotavlja dodatna plast silicija z visoko koncentracijo primesi imenovana pomnoževalna plast. V tem delu smo se osredotočili na proučevanje območja med blazinicami v prototipih. Vzorce smo obsevali z reaktorskimi nevtroni do ekvivalentne fluence $2,5 \cdot 10^{15} \, 1 \, \mathrm{MeV} n_{eq} \, \mathrm{cm^{-2}}$ in proučili posledice sevalnih poškodb na efektivno razdaljo med blazinicami. Osnovne lastnosti detektorjev smo pridobili iz meritev karakteristik C-V in I-V. Odvisnost efektivne razdalje med blazinicami od zunanje napetosti in fluence smo sistematično izmerili s tehniko prehodnega toka z uporabo laserske svetlobe različnih valovnih dolžin. Ugotovili smo, da je razlog za razliko med izmerjenimi in nominalnimi razdaljami med blazinicami posledica ukrivljanja silnic električnega polja na robovih blazinic. Opravili smo tudi simulacije in rezultate primerjali z meritvami. This master’s thesis presents a study on the effective inter-pad distance of low gain avalanche detector (LGAD) prototypes for the High Granularity Timing Detector at the ATLAS experiment. Prototypes from two producers were investigated. LGADs are the technology of choice for track timing detectors at the upgraded High-Luminosity Large Hadron Collider due to their superior timing resolution provided by the additional highly doped layer called the gain layer. Measurements presented in this work focus on the inter-pad region of the prototypes. Effects of radiation damage on the effective inter-pad distance have been studied by measuring samples irradiated with reactor neutrons to an equivalent fluence of $2,5 \cdot 10^{15} \, 1 \, \mathrm{MeV} n_{eq} \, \mathrm{cm^{-2}}$. Basic properties of the detectors were extracted by measuring the C-V and I-V characteristics. The dependence of the effective inter-pad distance on bias voltage and fluence was systematically measured with the Transient Current Technique using laser light of different wavelengths. Bending of the electric field lines at the edges of the electrodes was found to be the reason for the difference between measured and nominal inter-pad distances. The effective inter-pad distances were also simulated and compared to the measurements. Silicijevi detektorji delcev plazovni detektorji z nizko stopnjo pomnoževanja sevalne poškodbe meritve časa preleta časovna resolucija pomnoževanje naboja Visoko-luminoznostni veliki hadronski trkalnik ATLAS Visoko zrnati detektor časa Silicon particle detectors Low Gain Avalanche Detectors radiation damage timing measurements time resolution charge multiplication High-Luminosity Large Hadron Collider ATLAS experiment High Granularity Timing Detector true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2023-09-13 08:15:29 2023-09-13 08:15:35 2023-09-15 03:19:11 0000-00-00 00:00:00 2023 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 135849 163954947 9640.pdf 9640.pdf 1 F798E9DE989AC6858F61943D1DE7C169 777caa4504e26754b65079fe5c5114c504dfe464e24054ecf6f603d7884f3a28 f3dea9b1-51fc-11ee-916e-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=174547 Fakulteta za matematiko in fiziko 0 0 0