InGaN/GaN MQWs for scintillators perspectives and problems

0463677 - FZÚ 2017 RIV DE eng A - Abstrakt
Hospodková, Alice - Zíková, Markéta - Hubáček, Tomáš - Kuldová, Karla - Oswald, Jiří
InGaN/GaN MQWs for scintillators perspectives and problems.
GCCCG-1/DKT2016. Dresden: TU Dresden, 2016. s. 101.
[German Czechoslovak Conference on Crystal Growth (GCCCG-1) /1./. 16.03.2016-18.03.2016, Dresden]
Grant CEP: GA ČR GA16-11769S
Institucionální podpora: RVO:68378271
Klíčová slova: MOVPE * GaInN multiple quantum well * GaN * scintillator
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus

The III-nitrides became very important compound semiconductors in last twenty years and are used in many applications indispensable in nowadays life such as effective white diodes, blue lasers or high electron mobility transistors (HEMTs).
Large band gap semiconductors such as GaN or ZnO are suitable for scintillator and detector structures for ionizing radiation detection. While ZnO is used in scintillators for several decades, the promising application of GaN epitaxial layers in scintillator structures has attracted scientific attention in last few years. Besides the strong exciton binding energy GaN has also an advantage of high radiation resistance. So the detectors of ionizing radiation and scintillators seem to be a new and perspective application of nitride semiconductors.
In principle the scintillating nitride heterostructure could be based on InGaN/GaN multiple quantum well (QW) structure similarly to LED but with some differences in structure design. The structure should contain higher number of QD layers compared to LEDs, In content in QW should be higher to obtain sufficient carrier confinement for thin thickness of QWs. The p-n junction is not required; however, some n-type doping is necessary in case of detection of charged particle radiation like electrons or protons. Active part of the structure for scintillators has to be much thicker than in LEDs. Another problem for fast scintillators is the slow defect green-yellow photoluminescence band, which become dominant when the luminescence is excited by ionizing radiation, see Fig. 1. Results obtained on several type of structures designed for scintillators will be discussed.

Trvalý link: http://hdl.handle.net/11104/0262785