An enhanced surface passivation effect in InGaN/GaN disk-in-nanowire light emitting diodes for mitigating Shockley-Read-Hall recombination
Ng, Tien Khee
Holmes, Justin D.
Parbrook, Peter J.
The Royal Society of Chemistry
We present a detailed study of the effects of dangling bond passivation and the comparison of different sulfide passivation processes on the properties of InGaN/GaN quantum-disk (Qdisk)-in-nanowire based light emitting diodes (NW-LEDs). Our results demonstrated the first organic sulfide passivation process for nitride nanowires (NWs). The results from Raman spectroscopy, photoluminescence (PL) measurements, and X-ray photoelectron spectroscopy (XPS) showed that octadecylthiol (ODT) effectively passivated the surface states, and altered the surface dynamic charge, and thereby recovered the band-edge emission. The effectiveness of the process with passivation duration was also studied. Moreover, we also compared the electro-optical performance of NW-LEDs emitting at green wavelength before and after ODT passivation. We have shown that the Shockley–Read–Hall (SRH) non-radiative recombination of NW-LEDs can be greatly reduced after passivation by ODT, which led to a much faster increasing trend of quantum efficiency and higher peak efficiency. Our results highlighted the possibility of employing this technique to further design and produce high performance NW-LEDs and NW-lasers.
Efficiency , Nanowires , Passivation , Quantum efficiency , X ray photoelectron spectroscopy , Band-edge emissions , Electro optical performance , Nanowire light emitting diodes , Non-radiative recombinations , Photoluminescence measurements , Shockley-Read-Hall recombinations , Sulfide passivations , Light emitting diodes
ZHAO, C., NG, T. K., PRABASWARA, A., CONROY, M., JAHANGIR, S., FROST, T., O'CONNELL, J., HOLMES, J. D., PARBROOK, P. J., BHATTACHARYA, P. & OOI, B. S. 2015. An enhanced surface passivation effect in InGaN/GaN disk-in-nanowire light emitting diodes for mitigating Shockley-Read-Hall recombination. Nanoscale, 7, 16658-16665. http://dx.doi.org/10.1039/C5NR03448E