Transient current technique (TCT) characterization of high-energy photon irradiated silicon detectors

master's thesis

• Title (croatian): Karakterizacija silicijskih detektora ozračenih visokoenergetskim fotonima metodom tranzijentne struje (TCT)
• Author: Ana Petrinec
• Mentor: Jaakko Juhana Harkonen (mentor)
• Mentor: Mihael Makek (mentor)
• Committee member: Mihael Makek (predsjednik povjerenstva)
• Committee member: Jaakko Juhana Harkonen (član povjerenstva)
• Committee member: Nils Paar (član povjerenstva)
• Committee member: Damir Bosnar (član povjerenstva)
• Committee member: Tomislav Marketin (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2018-08-28, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

Incident radiation delivers energy to matter through different interactions. This can disrupt regular crystal structure of a semiconductor detector, which degrades its properties. The purpose of this thesis is to study the effect of gamma radiation on the properties of silicon detectors. Samples used are n- and p-type diodes made of Czochralski silicon. They were produced in Finnish Center for Micro- and Nanotechnology Micronova. Transient Current Technique (TCT) with red and infrared laser (wavelengths 660 and 1064 nm) is used to characterize the detectors. From recorded transients the information can be obtained about collected charge, full depletion voltage, electric field distribution and sign of the space charge, to name a few. With increasing radiation dose, detector may experience charge loss, full depletion voltage changes and an increase in the leakage current. For maximum dose at which detectors were irradiated (187 kGy), the only observable effect was increase of the leakage current. N-type detectors proved to be more resilient to gamma irradiation than p-type one.

Abstract (croatian)

Kroz različite interakcije upadno zračenje materiji predaje energiju. To može oštetiti pravilnu kristalnu strukturu čime se narušavaju svojstva poluvodičkog detektora. Svrha je ovog rada proučavanje utjecaja ozračivanja visokoenergijskim gama zrakama na svojstva silicijskih detektora. Korišteni uzorci su diode n- i p-tipa napravljene od Czochralskog silicija u finskom centru za mikro- i nanotehnologiju Micronova. Za karakterizaciju detektora korištena je metoda tranzijentne struje (TCT) s crvenim i infracrvenim laserom (valnih duljina 660 i 1064 nm). Iz dobivenih signala mogu se, me-du ostalim, dobiti informacije o prikupljenom naboju, radnom naponu, raspodjeli električnog polja unutar volumena detektora i predznaku prostornog naboja u zoni osiromašenja. S porastom primljene doze zračenja detektoru se mijenja napon potpunog osiromašenja, gubi naboj te dolazi do porasta struje kroz detektor u nepropusnoj polarizaciji. Na maksimalnoj dozi kojom su detektori ozračeni (187 kGy) jedina sa sigurnošću uočena posljedica bila je porast struje u nepropusnoj polarizaciji. Detektori n-tipa pokazali su se otpornijima na gama zračenje od detektora p-tipa.

• Keywords: silicon detectors; transient current technique (TCT); radiation hardness
• Keywords (croatian): silicijski detektori zračenja; metoda tranzijentnih struja (TCT); otpornost na zračenje
• Language: english
• URN:NBN: urn:nbn:hr:217:370582
• Study programme: Title: Physics; specializations in: Research; Course: Research; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra fizike (magistar/magistra fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-11-20 16:35:34