Formation of Si nanowire by atomic manipulation with a high temperature scanning tunneling microscope

Abstract

The formation of Si nanowire during indentation of the scanning tunneling microscope tip onto the Si(111) surface was investigated by changing the sample bias, the temperature, and the tip retraction speed. The wire length at room temperature is in the order of 1 nm, however, the wire was elongated remarkably with either increasing temperature or bias voltage while keeping a positive sample bias. The wire was also elongated when the tip speed was decreased. The typical length was ∼14 nm at 481 °C, +2.0 V and 320 nm/s. In order to explain these results, we proposed a simple model for the wire formation by taking into account the surface diffusion and electromigration effects.