InGaN/GaN structures: effect of the quantum well number on the cathodoluminescent properties

0492160 - FZÚ 2019 RIV DE eng J - Journal Article
Hospodková, Alice - Hubáček, Tomáš - Oswald, Jiří - Pangrác, Jiří - Kuldová, Karla - Hývl, Matěj - Dominec, Filip - Ledoux, G. - Dujardin, C.
InGaN/GaN structures: effect of the quantum well number on the cathodoluminescent properties.
Physica Status Solidi B. Roč. 255, č. 5 (2018), s. 1-5, č. článku 1700464. ISSN 0370-1972. E-ISSN 1521-3951
R&D Projects: GA MŠMT LM2015087; GA ČR GA16-11769S; GA MŠMT(CZ) LO1603
EU Projects: European Commission(XE) 690599 - ASCIMAT
Institutional support: RVO:68378271
Keywords : MOVPE * nitrides * scintillator * quantum well * cathodoluminescence
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.454, year: 2018

Luminescence results on InGaN/GaN MQW structures with 10 and 30QWs were obtained. The aim is to increase the intensity of faster blue QW emission and decrease the luminescence of the QW defect band, showing a slower luminescence decay time, which is undesired for fast scintillator applications. We demonstrate that increasing the number of InGaN QWs is an efficient method to reach this goal. The luminescence improvement of the sample with higher number of QWs is explained by the influence of the increased size of V-pits with increased QW number. Thinner QWs on the side wall of V-pits serve as barriers which separate carriers from dislocations penetrating through the V-pit centre, supressing thus the non-radiative and radiative recombination on defects. Based on cathodoluminescence (CL) results, the scintillator structure design is discussed. Scintillator structures with higher number of QWs can take advantage of both, improved luminescence efficiency and thicker active region.
Permanent Link: http://hdl.handle.net/11104/0285718