Atomic-scale observation and control of the reaction of phosphine with silicon

抄録

The ability to identify and control the pathway by which chemical reactions occur at the level of individual atoms will be of enormous benefit in the coming age of nanotechnology. Here, we present a detailed atomic-resolution scanning tunneling microscopy (STM) study of one such pathway: the adsorption, surface diffusion and dissociation of phosphine (PH₃) on silicon (001). We show that PH₃ dissociates on Si(001) to produce PH₂ + H, PH + 2H and P + 3H moieties. In addition, we show that PH₂ molecules are readily able to diffuse on Si(001) at room temperature, resulting in the formation of hemihydride dimers on low dosed Si(001) surfaces. In addition we show that control over the processes of diffusion and surface incorporation can be achieved using STM-based hydrogen lithography; a technique that is now used in many STM laboratories. [DOI: 10.1380/ejssnt.2006.609]