Light-emitting diode having zinc oxide nanorods and method of fabricating the same
US8614452B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2011 |
| Grant date | Dec 24, 2013 |
| Priority date | — |
| Expiry date | Dec 14, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/816
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
The light extraction efficiency of a typical light-emitting diode (LED) is improved by incorporating one-dimensional ZnO nanorods. The light extraction efficiency is improved about 31% due to the waveguide effect of ZnO sub-microrods, compared to an LED without the nanorods. Other shapes of ZnO microrods and nanorods are produced using a simple non-catalytic wet chemical growth method at a low temperature on an indium-tin-oxide (ITO) top contact layer with no seed layer. The crystal morphology of a needle-like or flat top hexagonal structure and the density and size of ZnO microrods and nanorods are easily modified by controlling the pH value and growth time. The waveguide phenomenon in each ZnO rod is observed using confocal scanning electroluminescence microscopy (CSEM) and micro-electroluminescence spectra (MES).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.