"One-tenth of silicon semiconductor thickness" Ultra-thin semiconductor development
- 자연과학대학
- Hit3858
- 2017-01-16
IBS · Sungkyunkwan University joint research team developed "Grape-molybdenum disulfide optical sensor"
Korean researchers have developed ultra-thin semiconductors using only one-tenth the thickness of silicon semiconductors using next-generation semiconductor materials.
The joint research team of IBS nanostructured physics research group (Team leader: Professor Lee Younghee), Sungkyunkwan University professor Yu Woojong and UCLA Professor Xiang Feng Duan of U.S.A., said they have developed 1.3 nanometer (nm, 1 billionth of a meter) Grape-molybdenum ultra-thin semiconductors on 9th.
Graphene, a carbon nanomaterial removed from the surface layer of graphite, is called 'new material for dream' because of its excellent electrical and chemical properties, but it is difficult to use as a semiconductor device because there is no bandgap that is the energy difference of electrons.
The team has overcome the limitations of graphene by introducing molybdenum disulfide (MoS2), which is a two-dimensional material, such as graphene, with a band gap. Molybdenum disulfide and graphene were piled up and used as semiconductors and electrode materials to develop semiconductor optical sensors.
The graphene-molybdenum disulfide semiconductor has a thickness of 1.3 nanometers, only one-tenth of the 14 nanometer (nm) limit of the three-dimensional silicon semiconductor. The problem of excessive power consumption and heat generation of the silicon semiconductor can be solved, and the voltage required for the operation can be greatly reduced. Ultra-thin semiconductors are expected to contribute to the development of high-efficiency optical devices.
Since the photocurrent efficiency generated between graphene and molybdenum disulfide is high, it is not necessary to use the p-n junction method used in the conventional optical device fabrication. A p-n junction is a heterojunction between two semiconductor materials with different electrical properties, and is used to fabricate optical devices that absorb external light to generate electrical signals or energy. However, since the p-n junction structure requires a thickness of 14 nm or more, it has been difficult to develop an optical device with a thin two-dimensional material.
Professor Yu Woojong said, "We will be able to apply it to the development of ultra-small semiconductor, high-efficiency optoelectronic devices, and new transparent electronic devices for wearable devices and the Internet."
From the left Professor Lee Younghee, Professor Yu Woojong
The findings are published in the prestigious international journal Nature Communications.