Mechanism for room-temperature single-atom lateral manipulations on semiconductors using dynamic force microscopy.
Vacancy-mediated lateral manipulations of intrinsic adatoms of the Si(111)-(7x7) surface at room temperature are reported. The topographic signal during the manipulation combined with force spectroscopy measurements reveals that these manipulations can be ascribed to the so-called pulling mode, and that the Si adatoms were manipulated in the attractive tip-surface interaction regime at the relatively low short-range force value associated to the manipulation set point. First-principles calculations reveal that the presence of the tip induces structural relaxations that weaken the adatom surface bonds and manifests in a considerable local reduction of the natural diffusion barriers to adjacent adsorption positions. Close to the short-range forces measured in the experiments, these barriers are lowered near the limit that enables a thermally activated hopping at room temperature.
Sugimoto
Yoshiaki
Y
Graduate School of Engineering, Osaka University, 2-1 Yamada-Oka, 565-0871 Suita, Osaka, Japan.
Jelinek
Pavel
P
Pou
Pablo
P
Abe
Masayuki
M
Morita
Seizo
S
Perez
Ruben
R
Custance
Oscar
O