The role of Shockley-Read-Hall non-radiative recombination centers on electroluminescence (EL) efficiency in blue multi-quantum-well (MQW) 436 nm GaN/InGaN light emitting diodes (LEDs) was examined by controlled introduction of point defects through 6 MeV electron irradiation. The decrease in the EL efficiency in LEDs subjected to irradiation with fluences above 5 × 1015 cm-2 was closely correlated to the increase in concentration of Ec-0.7 eV electron traps in the active MQW region. This increase in trap density was accompanied by an increase in the both diode series resistance and ideality factor (from 1.4 before irradiation to 2.1 after irradiation), as well as the forward leakage current at low forward voltages that compromise the injection efficiency. Hole traps present in the blue LEDs do not have a significant effect on EL changes with radiation because of their low concentration.
Bibliographical noteFunding Information:
The work at NUST MISiS was supported in part by the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST(MISiS) (K2-2014-055). The work at Korea University was supported by the National Research Foundation of Korea (NRF) funded by Ministry of Science, ICT & Future Planning (2017R1A2B3006141). The work at UF was supported by DTRA Grant No. HDTRA1-17-1-0011.
© 2017 Author(s).
ASJC Scopus subject areas
- Physics and Astronomy(all)