Pb-induced Reconstructions on Si(111)-(√3×√3)/Au Surface

• Main Authors: LIANG, HAO-CHUN, 梁皓鈞
• Other Authors: MEN, FU-KWO
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/rt34de

碩士 === 國立中正大學 === 物理系研究所 === 104 === 　　By depositing Au onto a Si(111)-(7×7) surface, the surface reconstructs into different structures as Au coverage increases. We observe a (√3×√3) reconstruction by depositing 0.5~1ML of Au. This reconstruction is consisted of (√3×√3) domains separated by domain walls. The domain wall density increases with the Au coverage. 　　To do our experiment we prepare the (√3×√3) reconstruction by depositing 0.75ML of Au. Pb atoms are deposited onto this surface, which results in the formation of a (2√21×2√21) reconstruction. This (2√21×2√21) structure has been reported in the literature by depositing Au onto Si(111)-(7×7) surface at 700℃ and followed by annealing. The (2√21×2√21) reconstruction prepared by Au deposition transforms into the (√3×√3) after annealing at 350℃. It doesn’t reappear even after a second heating at 700℃ and followed by annealing. Consequently, the (2√21×2√21) reconstruction is metastable and transforms irreversibly into the (√3×√3). Here, we observe this (√3×√3) to (2√21×2√21) transition simply by depositing Pb and show that such transition is reversible.