Research on Power - Assisted Transparent LED Display
In 2015, professor Ali javey of UC Berkeley school of electrical engineering and computer science published a paper in science, revealing the possibility of using mono layer semiconductor to make ultra-thin LEDs. But the technology at that time, if the size of single-layer semiconductor is enlarged, its thickness will also increase at the same time, and its real application is limited.
However, a few days ago, its team said that it had successfully made LEDs which can expand the length and width without affecting the thickness, and only have three atoms thick. New research results have been published in the journal nature communication.
When the voltage is applied to the LEDs, the electrons will reach an excited state, and then when they meet the holes at the contact point, they will decay back to the ground state, and at the same time, the energy will be released in the form of light. This is how LEDs work. Therefore, the most difficult problem in improving the luminous efficiency of LEDs lies in how to make free electrons contact with holes more efficiently. Especially when the size of semiconductor is only a single layer thick, there are not many materials that can be used in it, which makes it more difficult.
Single layer semiconductor
Researchers use transition - metal disulfide ( TMD cs ) to make single-layer semiconductors. this kind of material has semiconductor characteristics similar to graphene and is considered as an important photoelectric material for the next generation. Then place gate and source on top and bottom of the semiconductor to make LEDs. when alternating current is indirectly connected between the gate and source, free electrons and holes will appear in the middle of the single-layer semiconductor at the same time, thus making it release energy as light.
Configuration of this LEDs.
Future development
At present, there are still many places where this LEDs need continuous improvement, especially its energy efficiency is only 1 % at present, which is far less than that of 25 ~ 30 % in the market. But as der - hsen lien, a postdoctoral researcher in his research team, said, " this material is quite thin and elastic, so it can be made transparent and applied to curved surfaces".
At present, transparent displays have become a new goal of scientific and technological circles, and the research results will have considerable influence.
In addition, at present, there have been studies on mass production of high-quality TMD cs by chemical vapor deposition, so it is expected to solve the physical limit problems currently faced by integrated circuits by its characteristics.