[14a-414-1~8] 6.6 Probe Microscopy

△ [14a-414-1] Chemical Identification of Single Atoms by Atomic Force Microscopy

〇Jo Onoda^1,2, Martin Ondracek³, Pavel Jelinek³, Yoshiaki Sugimoto^1,2 (1.Univ. of Tokyo, 2.Osaka Univ., 3.ASCR)

Keywords:atomic force microscopy, chemical identification, semiconductor

Atomic force microscopy (AFM) has accomplished single-atom chemical identification by force spectroscopy. So far, the chemical identification has been achieved on the Si surfaces with substitutional IV group elements such as Sn, Ge, and Pb. Despite of these successes, it has not been unambiguous whether the chemical identification method is applicable to other elements such as O. Actually, we found that the method did not hold for some chemical species whose electronegativity values are largely deviated from that of Si. Here, we will present more versatile methodology for single-atom chemical identification by AFM. The new method is based on the scatter plots of bond energies acquired on target X atoms and reference Si atom on the surfaces with different AFM tips. These scatter plots of bond energies can be fitted by straight lines, respectively. We found that the slops represent the “fingerprints” of the chemical identities.