23 February 2020

[Semiconductor] – A nanoscale gold butterfly can make its own semiconductor skin

Home / News / [Semiconductor] – A nanoscale gold butterfly can make its own semiconductor skin
Flèche contenu
Gold butterfly semiconductor - Codex International

Hokkaido University researchers have devised a unique approach for making nanosized semiconductors on a metal surface. The details of the method were reported in the journal Nano Letters (“Localized ZnO Growth on a Gold Nanoantenna by Plasmon-Assisted Hydrothermal Synthesis”) and could further research into the fabrication of nanosized light and energy emitters.
The approach, developed by Hokkaido University’s Research Institute for Electronic Science and Hokkai-Gakuen University, involves generating localized heat on a gold nanoparticle within a butterfly-shaped nanostructure. The heat causes hydrothermal synthesis in which semiconducting zinc oxide crystallizes on the gold nanoparticle.
Scientists have been investigating ways to carefully place nano-sized semiconductors on metallic particles to utilize them in nano-lasing and nano-lithography, for example. But current methods lack precision or are too costly.
The approach developed by the Japanese team overcomes these issues.
The team first conducted simulations to determine the optimal conditions for precisely controlling the generation of heat in nanostructures. They utilized a phenomenon called surface plasmon resonance, a process which partly converts light to heat in metallic materials.
According to the simulations, a butterfly-shaped nanostructure consisting of two rhombus gold particles placed on either side of a gold nanorod would lead to optimal conditions. In this system, the nanorod, or the body of the butterfly, works as a nanoheater using a specific polarized light. After rotating the light polarization 90 degrees, the rhombus particles, or the wings of the butterfly, should work as an antenna to gather light at subwavelength spots in the butterfly’s semiconductor skin.
To test this theory, they fabricated the gold butterfly and placed it in water inside a glass chamber. A solution made from equal parts zinc nitrate hexahydrate and hexamethylene tetramine was added to the chamber, which was then sealed and placed on a microscopic stage. When the laser light was shone on the system inside the chamber, the nanorod heated up and semiconducting zinc oxide particles crystallized along its surface as they expected.
This demonstrated that the butterfly-shaped gold nano-antenna can precisely control where plasmon-assisted hydrothermal synthesis occurs, therefore enabling the localized formation of nanosized semiconductors.
“Further research is expected to lead to the development of powerful nano-sized light sources, highly efficient photoelectric conversion devices, and photocatalysts,” says Hokkaido University’s Keiji Sasaki of the research team. “It could also lead to applications in semiconductor electronics and optical quantum information processing.”
Source: Hokkaido University

Discover Also
[Nano-Medecine] – Newly developed nanoparticles help fight lung cancer in animal model 26 November 2019

Scientists have reported a new approach to treating lung cancer with inhaled nanoparticles developed at Wake Forest School of Medicine, part of Wake Forest Baptist Health.

Read more
[Thin Films] – New etching technique will change the way semiconductor devices are made 22 February 2020

Microelectronics like semiconductor devices are at the heart of the technologies we use each day. As we move into an era where we are stretching the limits of Moore’s Law, it is essential to find new ways to continue to pack more circuitry into each individual device in order to increase the speed and capability of our computers.

Read more