Scientists Use Zinc Oxide Nanowires to Enhance Performance of LEDs

Researchers from the Georgia Institute of Technology have utilized piezoelectric materials such as zinc oxide nanowires to radically enhance the effectiveness at which gallium nitride LEDs enable conversion of electricity into ultraviolet light.

The research team improved the performance of its optoelectronic devices by generating a piezoelectric potential in the piezoelectric material through the application of mechanical strains. Controlling an optoelectronic unit with piezoelectric potential is called as piezo-phototronics and is used to improve carrier injection and modify the transportation of charges at the p-n junction in the LEDs.

A light-emitting diode (LED) whose performance has been enhanced through the piezo-phototronic effect is studied in the laboratory of Regents professor Zhong Lin Wang.

The researchers have used the piezo-phototronic effect to improve the recombination rate of holes and electrons to produce photons, which in turn improves the LEDs’ external efficiency by means of superior injection current and enhanced light emission. The gallium nitride thin film forms the ‘p’ part of a p-n junction, while the zinc oxide nanowires form the ‘n’ part. At this junction point, free carriers were entrapped in a stream generated by the piezoelectric charge produced as a result of applying mechanical strain on the wires.

The research team manufactured its single zinc oxide micro/nanowire LED by using a wire over a trenched substrate. The team developed a magnesium-doped gallium nitride film epitaxially over a substrate using metal organic chemical vapor deposition, and then used the film along with the zinc oxide nanowire to create a p-n junction.

The research team placed the cathode material, a sapphire substrate, alongside the gallium nitride substrate with an accurate gap, where the zinc oxide nanowire was placed with close proximity with the gallium nitride. The nanowire was covered with a transparent polystyrene tape. An alumina rod linked to a piezo nanopositioning stage is used to apply the force on the tape, which in turn compressed the wires.

The team then investigated the light emission changes by altering the strain values on 20 various devices. The devices formed with the reverse orientation of the nanowires demonstrated a decrease in efficiency, while the other showed improved efficiency. This variation was because of the reversal in the piezo potential sign due to the shift of the orientation of the nanowires from +c to –c.

The LEDs produced by the Georgia Tech research team generated emissions at ultraviolet wavelengths of 390 nm. However, Zhong Lin Wang, who serves as a Regents professor at the Georgia Tech School of Materials Science and Engineering, hopes that the wavelengths can be increased into the visible light region for an array of LEDs. He also believes that the innovative method developed by the research team can be used with other electrically controlled optical devices.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Georgia Institute of Technology. (2019, February 12). Scientists Use Zinc Oxide Nanowires to Enhance Performance of LEDs. AZoNano. Retrieved on July 18, 2024 from

  • MLA

    Georgia Institute of Technology. "Scientists Use Zinc Oxide Nanowires to Enhance Performance of LEDs". AZoNano. 18 July 2024. <>.

  • Chicago

    Georgia Institute of Technology. "Scientists Use Zinc Oxide Nanowires to Enhance Performance of LEDs". AZoNano. (accessed July 18, 2024).

  • Harvard

    Georgia Institute of Technology. 2019. Scientists Use Zinc Oxide Nanowires to Enhance Performance of LEDs. AZoNano, viewed 18 July 2024,

Tell Us What You Think

Do you have a review, update or anything you would like to add to this news story?

Leave your feedback
Your comment type

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.