Deposition of Nano-Scale Ga Dots onto HF-Treated Si(111) Using a Scanning Tunneling Microscope

ABSTRACTNano-scale Ga dots are deposited through the decomposition of triethylgallium (TEGa) adsorbed on HF-treated Si(111) surfaces using a scanning tunneling microscope (STM). The deposition of Ga dots of 2–13 nm in diameter is achieved by applying a negative voltage pulse to the sample, while no deposition is observed when a positive voltage pulse is applied. The conditions for Ga deposition are systematically investigated by varying the gap conductance, pulse height, and pulse width. A tentative model for the mechanism of Ga deposition is proposed, in which TEGa molecules are decomposed by the electric field between the tip and the sample.