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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2005. V. 8, N 3. P. 001-011.
Physico-chemical model and computer simulations
of silicon nanowire growth
1V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 45, prospect Nauky, 03028 Kyiv, Ukraine
Abstract. A model of catalytically enhanced CVD growth of a silicon nanowire
assembly on a substrate is developed, and growth process is simulated. Thermodynamickinetic theory is used for modeling of molecular transport in the gas phase, processes
near catalyst surface and nanowire side of variable curvature, bulk diffusion of silicon
adatoms through catalyst – body, and 2D nucleation. The simulation of atomic transport
across surfaces is based on a long-wave approach of lattice gas approximation. To
determine a character of atomic transport in TiSi2-catalyst that is of great importance for
application in Si-based technology, a density functional theory is used. The main result
of modeling is that it is found a relationship between growth conditions (an initial radius
of catalyst particles, their density, substrate temperature, content, pressure of gas, as well
as properties of materials used) and, on the other hand, a growth rate, shape,
composition, and type of atomic structure (amorphous or crystalline) of the nanowires
grown. Besides, available experimental data published previously are discussed, and a
qualitative agreement between theory and various experiments is obtained. This
agreement gives rise to use the found relationship for controlling the nanowire growth.
Keywords: silicon, nanowire.
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