STS results and STM images of the silicene superstructrue on the Ag(111)/Si(111) surface

• Main Authors: SU, Tai-Lung, 蘇泰龍
• Other Authors: Fu, Tsu-Yi
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/96782146718179399094

碩士 === 國立臺灣師範大學 === 物理學系 === 104 === From previous study, we know that we can grow silicene on the metal surface. In this experiment, we grow 6 ML of Ag (111) on Si (111) - (7 × 7) to substituted single-crystal silver bulk, then grow silicene on the silver film. First, we anneal and flash the silicon substrate to form Si (111) - (7 × 7) structure. then deposited 6 ML silver on Si (111) - (7 × 7) structure at 100 K. We warm the sample up to room temperature. Afterward, we anneal the sample to 570 K. Further, we cool down the sample to room temperature. Finally, we complete the preparation of the silver thin film. To Growing the silicene, we need to heat the silver thin film over 500 K. In this experiment, we keep the silver thin film at 550 K and deposit 1 ML Si on it. When the sample cool down, we finish the production of silicene. We can find 4 different silicene structures by STM. They are 4×4 , and two structure. These 4 structure’s STS result are similar. Because we choose silver thin film replace silver bulk. So we can find Ag(1×1) dislocation by LEED . And we also can find same result by STM. But Ag(1×1) dislocation don’t affect STS result. Different thickness of the silver thin film will show different characteristics. We can find silicene on 6 ML silver thin film, but don’t find silicene on 1 ML silver thin film. So we can use 6 ML silver thin film replace silver bulk.