Electrodeposited, Transverse Nanowire Electroluminescent Junctions
- Author(s): Qiao, Shaopeng
- Advisor(s): Penner, Reginald M.
- et al.
The preparation by electrodeposition of transverse nanowire electroluminescent junctions (tn-ELJs) is described and the electroluminescence (EL) properties of these devices are characterized. The lithographically patterned nanowire electrodeposition process (LPNE) is first used to prepare a long (mm's), linear, nanocrystalline CdSe nanowires on glass. The thickness of these nanowires along the emission axis is 60 nm and the width along the electrical axis is adjustable from 100 - 450 nm. Ten pairs of nickel-gold electrical contacts are then positioned along the axis of this nanowire using lithographically directed electrodeposition. The resulting linear array of nickel-CdSe-gold junctions produce electroluminescence (EL) with an external quantum efficiency, EQE, and threshold voltage that depends sensitively on the width of CdSe. EQE increases with increasing electric field and also with increasing width of CdSe, and threshold voltage also increases with the width of CdSe, and therefore the electrical resistance, of the tn-ELJs. Threshold voltage down to 1.8V (for the CdSe width around 100 nm) and EQE of 5.5*10^5 (for CdSe width around 450 nm) are obtained. tn-ELJs produce a broad EL emission envelope, spanning the wavelength range from 600 - 960 nm.