A matrix of blue GaN/InGaN multi-quantum-well (MQW) micro-Light-Emitting Diodes (micro-LEDs) with diode dimensions ranging from 2 to 100 µm was prepared by masked dry etching and characterized by Photoluminescence (PL), Microcathodoluminescence (MCL), capacitance-voltage profiling in the dark and under monochromatic illumination, current-voltage measurements, admittance spectra, Deep Level Transient Spectroscopy with electrical (DLTS) and optical (ODLTS) injection. The changes observed in the PL, MCL spectra are due to the formation of deep hole traps at Ev+ 0.75 eV and electron traps at Ec-1 eV in the sidewalls of the micro-LEDs. The former give rise to the red defect band peaked near 600 nm and contribute to the increase of tunneling and leakage current with decreasing the diode diameter. The latter are prominent centers of nonradiative recombination.
Bibliographical noteFunding Information:
The work at Korea University was supported by the Technology Innovation Program ( 20004479 , Micro LED chip and module fabrication technology with integrated field effect transistor for IoT application) funded by the Ministry of Trade, Industry and Energy ( MOTIE , Korea). . The work at NUST MISiS was supported by a grant from the Ministry of Science and Higher Education of the Russian Federation (Grant Application #220-7108-1760 )
© 2022 Elsevier B.V.
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry