Nanopillar growth by focused helium ion-beam-induced deposition

Nanopillar growth by focused helium ion-beam-induced deposition

Chen, P.
Van Veldhoven, E.
Sanford, C.A.
Salemink, H.W.M.
Maas, D.J.
Smith, D.A.
Rack, P.D.
Alkemade, P.F.A.

Applied Sciences

QN/Quantum Nanoscience

2010-10-14

A 25 keV focused helium ion beam has been used to grow PtC nanopillars on a silicon substrate by beam-induced decomposition of a (CH3)3Pt(CPCH3) precursor gas. The ion beam diameter was about 1 nm. The observed relatively high growth rates suggest that electronic excitation is the dominant mechanism in helium ion-beam-induced deposition. Pillars grown at low beam currents are narrow and have sharp tips. For a constant dose, the pillar height decreases with increasing current, pointing to depletion of precursor molecules at the beam impact site. Furthermore, the diameter increases rapidly and the total pillar volume decreases slowly with increasing current. Monte Carlo simulations have been performed with realistic values for the fundamental deposition processes. The simulation results are in good agreement with experimental observations. In particular, they reproduce the current dependences of the vertical and lateral growth rates and of the volumetric deposition efficiency. Furthermore, the simulations reveal that the vertical pillar growth is due to type-1 secondary electrons and primary ions, while the lateral outgrowth is due to type-2 secondary electrons and scattered ions.

condensed matter: electrical, magnetic and optical
surfaces, interfaces and thin films
nanoscale science and low-D systems

http://resolver.tudelft.nl/uuid:f74452e0-cd6a-4a58-a91b-05015af135be

https://doi.org/10.1088/0957-4484/21/45/455302

Institute of Physics

0957-4484

http://iopscience.iop.org/0957-4484/21/45/455302/

Nanotechnology, 21 (45), 2010

Institutional Repository

journal article

(c) 2010 The Author(s)
Institute of Physics