| AVS 56th International Symposium & Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS1+PS+TF+AS+NS-TuA |
| Session: | Non-Thermal Chemistry / Ion, Electron Processes |
| Presenter: | W.F. van Dorp, Delft University of Technology, The Netherlands |
| Authors: | W.F. van Dorp, Delft University of Technology, The Netherlands J.B. Wagner, Danish Technical University, Denmark T.W. Hansen, Danish Technical University, Denmark R.E. Dunin-Borkowski, Danish Technical University, Denmark K. Hagen, Delft University of Technology, The Netherlands |
| Correspondent: | Click to Email |
Focused electron beam-induced deposition (FEBID) is a technique where adsorbed precursor molecules are dissociated by a focused beam of electrons to define metallic or semi-conducting patterns. Control over the process has developed to the extent that the amount of deposited material can be controlled nearly to the level of single molecules. Currently, the highest resolution that is reported is 0.7 nm [1] using the precursor W(CO)6. At this scale, deposits contain no more than a few molecules on average. Our ultimate goal is to develop the ability to deposit single precursor molecules in a consistent manner.
We perform our FEBID experiments in environmental scanning transmission electron microscopes (E-STEM) with a beam energy of 200 keV and a 0.2 nm probe. The annular dark field (ADF) signal is used for the imaging of the deposits. By recording the ADF signal during deposit growth we are able to monitor the growth process in situ. Thin, electron transparent graphite is used as a substrate and typical precursor gas pressures at the sample during the deposition were 10-3 to 10-5 Torr.
In the present study we used Me3PtMeCp, a Pt-precursor that is often used in FEBID experiments [2]. To improve on the currently achieved resolution, it is important to study the nucleation stage of deposits. When using a graphite substrate we found that there is a significance difference in deposition behavior between the W(CO)6 and Me3PtMeCp precursors. Where the typical growth behavior for W(CO)6 is to form nm-sized or even sub-nm sized deposits, the deposits fabricated from Me3PtMeCp are a few nanometers in diameter and consist of individual sub-nm sized grains. We report on our study of this difference in growth behavior and strategies to increase the writing resolution.
[1] W.F. van Dorp, C.W. Hagen, P.A. Crozier, P. Kruit, Nanotechnology 19 (2008) 225305[2] A. Botman, M. Hesselberth, J.J.L. Mulders, Microelectron Eng 85 (2008) 1139