Study of charge carrier transport properties and lifetimes in HR GaAs:Cr with Timepix3

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F49777513%3A23220%2F21%3A43964056" target="_blank" >RIV/49777513:23220/21:43964056 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21670/21:00355199

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1748-0221/16/12/C12023/meta" target="_blank" >https://iopscience.iop.org/article/10.1088/1748-0221/16/12/C12023/meta</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1748-0221/16/12/C12023" target="_blank" >10.1088/1748-0221/16/12/C12023</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Study of charge carrier transport properties and lifetimes in HR GaAs:Cr with Timepix3

Popis výsledku v původním jazyce

The response of a Timepix3 (256 × 256 pixels, pixel pitch 55 μm) detector with a 500 μm thick HR GaAs:Cr sensor was studied in proton beams of 125 MeV at the Danish Centre for Particle Therapy in Aarhus, Denmark and in a 120 GeV/c pion beam at the Super- Proton Synchrotron (SPS) at CERN. The sensor was biased at different voltages and irradiated at different angles. The readout chip was configured to operate in electron and hole collection modes. Measurements at grazing angles allowed to see elongated tracks with well-defined impact and exit points, so that charge carrier production depths could be determined in each pixel. We extracted the charge collection efficiencies and the charge carrier drift times as a function of the distance to the pixel plane. It was found that measured proton tracks are shorter in hole collection than in the case of electron collection, which is explained by the shorter lifetime of holes. At an angle of 60 degrees with respect to the sensor normal, the average track length in hole collection was ∼700 μm and 950 μm in electron collection mode. To understand the experimental findings, models describing the properties of HR GaAs:Cr were implemented into the Allpix2 simulation framework. We added previously presented experimental results describing the dependence of the electron drift velocity on the electric field and validated the response by comparing measurement and simulation for various X- and gamma-ray sources in the energy range of 10–60 keV. By comparison of the experimental and the simulated results, the mobility μh and the lifetime of holes τh were estimated as μh = (320 ± 10) cm2/V/s and τh = (4.5 ± 0.5) ns.

Název v anglickém jazyce

Study of charge carrier transport properties and lifetimes in HR GaAs:Cr with Timepix3

Popis výsledku anglicky

The response of a Timepix3 (256 × 256 pixels, pixel pitch 55 μm) detector with a 500 μm thick HR GaAs:Cr sensor was studied in proton beams of 125 MeV at the Danish Centre for Particle Therapy in Aarhus, Denmark and in a 120 GeV/c pion beam at the Super- Proton Synchrotron (SPS) at CERN. The sensor was biased at different voltages and irradiated at different angles. The readout chip was configured to operate in electron and hole collection modes. Measurements at grazing angles allowed to see elongated tracks with well-defined impact and exit points, so that charge carrier production depths could be determined in each pixel. We extracted the charge collection efficiencies and the charge carrier drift times as a function of the distance to the pixel plane. It was found that measured proton tracks are shorter in hole collection than in the case of electron collection, which is explained by the shorter lifetime of holes. At an angle of 60 degrees with respect to the sensor normal, the average track length in hole collection was ∼700 μm and 950 μm in electron collection mode. To understand the experimental findings, models describing the properties of HR GaAs:Cr were implemented into the Allpix2 simulation framework. We added previously presented experimental results describing the dependence of the electron drift velocity on the electric field and validated the response by comparing measurement and simulation for various X- and gamma-ray sources in the energy range of 10–60 keV. By comparison of the experimental and the simulated results, the mobility μh and the lifetime of holes τh were estimated as μh = (320 ± 10) cm2/V/s and τh = (4.5 ± 0.5) ns.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

<a href="/cs/project/EF16_019%2F0000766" target="_blank" >EF16_019/0000766: Inženýrské aplikace fyziky mikrosvěta</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Instrumentation

ISSN

1748-0221

e-ISSN

—

Svazek periodika

16

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

9

Strana od-do

1-9

Kód UT WoS článku

000758055400024

EID výsledku v databázi Scopus

2-s2.0-85122859814