Kelvin probe force microscopy imaging on locally doped silicon nanowires

Kelvin probe force microscopy (KPFM) [1] is used for the nanoscale characterization of silicon nanowires (NWs). Horizontal NW arrays have been prepared from a silicon-on-insulator (SOI) starting material. After transferring the NW structures into the Si top layer by means of electron-beam lithography and reactive ion etching, the samples have been locally implanted with B and As. Activation of dopants was carried out by a rapid thermal annealing for 5 s at 1000 °C. Athena simulations showed that for the applied implantation and annealing conditions a box-like dopant distribution with comparable concentration of activated dopants can be assumed [2]. Quantitative dopant profiling by means of KPFM is successfully employed to locate the junctions along the B-doped and As-doped Si NWs. In addition, the influence of local intrinsic electric fields [3] is discussed for the investigated SOI structures.
References
[1] C. Baumgart, M. Helm, H. Schmidt, Phys. Rev. B 80, 085305 (2009). [2] S. F. Feste, J. Knoch, S. Habicht, D. Buca, Q.-T. Zhao, S. Mantl, Solid-State Electronics 53, 1257 (2009). [3] C. Baumgart, A.-D. Müller, F. Müller, and H. Schmidt, Phys. Stat. Sol. A 208, 777 (2011).