Wang et al Supp Info

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Supplementary Information
High efficiency, full-color AlInGaN quaternary
nanowire light emitting diodes with spontaneous
core-shell structures on Si
Renjie Wang, Xuedong Liu, Ishiang Shih, and Zetian Mi*
Department of Electrical and Computer Engineering, McGill University, 3480
University Street, Montreal, Quebec H3A 0E9, Canada
*Correspondence to: E-mail: zetian.mi@mcgill.ca; Phone: 1-514-398-7114
S1. Radial elemental profiles of representative AlInGaN nanowires
The EDXS elemental profile along the radial direction of AlInGaN core-shell
nanowires exhibiting 515 nm-wavelength emission and carrier lifetimes of 0.35 ns,
0.63 ns and 0.96 ns are shown in Figs. S1(a), S1(b) and S1(c), respectively. As
observed in Figs. S1 and Fig. 3(c), Ga signal remains constant over the core and shell
regions, and the concentration of In is high in the core and then decreases towards the
lateral surfaces. Shown in Figs. S1(b) and S1(c) and Fig. 3(c), there is very little In
content in the sidewall regions. By contrast, it is seen in Fig. S1(a) that In is present in
the region close to sidewall. Different from the nanowires with carrier lifetime of 0.63
ns shown in Fig. S1(b), the Al signal of the nanowire of 0.96 ns shown in Fig. S1(c)
was drastically reduced in the core region accompanied by two sharp bumps in the
shell regions, and hence its Al-rich shells were thicker. The radial carrier confinement
benefits from such radial elemental profiles shown in Fig. S1(c). This explains the
increased carrier lifetime.
Figure S1: (a) Elemental profiles derived from EDXS line scanning analysis along the
radial direction of 515 nm emission AlInGaN nanowires with carrier
lifetime of (a) 0.35 ns (shell thickness: ~3 nm), (b) 0.63 ns (shell thickness:
~9 nm), and (c) 0.96 ns (shell thickness: ~13 nm), respectively.
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