The manipulation of Cu subsurface interstitial atoms with scanning tunneling microscope

在超高真空环境下使用扫描隧道显微镜研究了吸附有双甘氨肽分子的Cu(0 0 1)表面 .在一定的偏压条件下 ,针尖在该表面扫描后会形成纳米尺度的Cu团簇 ,这些团簇可以根据意愿排列成字母或图形 .团簇的高度同偏压、隧道电流以及时间等条件有密切关系 .在室温下可以稳定存在的团簇为制造纳米器件提供了技术上的可能性 .实验结果表明 ,形成团簇的Cu原子不是来自Cu衬底表面或是针尖 .化学吸附在Cu表面的双甘氨肽分子 ,受到隧道电场的作用会在Cu表面形成张应变场 ,Cu亚表面自间隙原子在张应变场作用下迁移到表面是形成团簇的原因 .In this paper, the Cu(001) surface covered with glycylglycine has been studied by scanning tunneling microscope(STM) under ultra-high vacuum condition. On that surface copper clusters in nanometer-scale, which could form alphabet or graph at our wishes, may be produced by the scanning of STM under a certain bias voltage condition. The height of these clusters has a close relation with bias voltage, tunnel current and time. It offers the opportunity to fabricate nanometer-scale apparatus by these clusters due to their stability at room temperature. The experimental result shows that the copper atoms which form these clusters come from neither copper substrate surface nor STM tip. We think that the tensile stress field in the copper substrate is produced due to the chemisorbed glycylglycine molecule in tunnel electric field and it is the migration of copper subsurface interstitial atoms under that tensile stress field that causes the formation of copper clusters.SCI(E)中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)302824-8315