Suppressed contamination of InGaN/GaN MQW region by growing the buffer layer at lower temperature

0501495 - FZÚ 2019 JP eng A - Abstract
Hospodková, Alice - Dominec, Filip - Hubáček, Tomáš - Zíková, Markéta - Pangrác, Jiří - Oswald, Jiří - Kuldová, Karla - Vetushka, Aliaksi - Hulicius, Eduard
Suppressed contamination of InGaN/GaN MQW region by growing the buffer layer at lower temperature.
ICMOVPE XIX - Technical Digest. Nara: Japanese Association for Crystal Growth, 2018 - (Miyake, H.). s. 147-147
[19th International Conference on Metalorganic Vapor Phase Epitaxy - ICMOVPE XIX. 03.06.2018-08.06.2018, Nara]
R&D Projects: GA MŠMT(CZ) LO1603; GA ČR GA16-15569S
EU Projects: European Commission(XE) 690599 - ASCIMAT
Institutional support: RVO:68378271
Keywords : GaN buffer layer * scintillators * low dimensional structures * V-pits * metalorganic vapor phase epitaxy * InGaN/GaN QWs
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)

Fast response of scintillators based on InGaN/GaN multiple quantum wells is compromised by slower luminescence defect band of unknown origin. SIMS analysis suggests that impurities concentrate in the quantum-well region, due to a drop in growth temperature. Using MOVPE we have prepared a set of samples with additional low-temperature buffer GaN layers to keep the impurities farther from the quantum wells. Our spectroscopic measurements have confirmed that this modification indeed results in enhancement of the fast luminescence component and reduction of the slow one. AFM images for two samples that differ mostly by morphology however points to another explanation, with formation of larger V-pits being the main reason for the luminescence improvement.
Permanent Link: http://hdl.handle.net/11104/0293517