TU-TESL

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According to foreign media reports, researchers at Cardiff University in the UK have for the first time found that the surface of a common semiconductor material has "instability" that has never been found before. The discovery may have a profound impact on the future development of electronic equipment materials that provide energy for daily life. From smartphones and GPS to satellites and laptops, composite semiconductors are an integral part of such devices. (photo: Cardiff University) the new discovery reveals that the surface of GaAs, a commonly used composite semiconductor material, is not as stable as previously thought. Using state-of-the-art equipment from the school of physics and Astronomy and the Institute of composite semiconductors at Cardiff University, the team found that there are small instabilities in the atomic structure of GaAs, which will appear and disappear in a short time. This is the first time that this "metastable" phenomenon has been observed on the surface of GaAs. Dr. Juan pereiro Viterbo of the school of physics and astronomy at Cardiff University, co-author of the study, said: "at present, we don't know whether this phenomenon will affect the growth of semiconductor device structure. Next we will carry out research. If this phenomenon occurs in the growth process of semiconductor devices, it will have a profound impact. Finally, this discovery can help us better understand the situation of molecular structure, so as to develop new materials and structures, reduce the defects of existing composite semiconductors, and develop better electronic products for communication systems, computers, telephones, automobiles, etc. " The key to this discovery is the possibility of creating new devices that will have new capabilities that did not exist before. There is a low-energy electron microscope in the laboratory of the Institute of physics and Astronomy and the Institute of composite semiconductors. Using the molecular beam epitaxy machine, researchers can observe the dynamic changes of material structure when manufacturing composite semiconductors. Molecular beam epitaxy (MBE) is a technology used to fabricate or "grow" composite semiconductor devices. Its working principle is to accurately emit extremely hot atomic or molecular beams on the substrate. Such molecules fall on the surface of the substrate, condense, and then slowly and systematically accumulate into a super thin layer, finally forming a complex single crystal structure. Dr Viterbo said: "although gallium arsenide has been studied in depth, the dynamic state that has never been observed before can be observed by using a low-energy electron microscope during the growth process."