Carbon saturation of arrays of Ni catalyst nanoparticles of different size and patternuniformity on a silicon substrate

Abstract

The kinetics of saturation of Ni catalyst nanoparticle patterns of the three different degreesof order, used as a model for the growth of carbon nanotips on Si, is investigatednumerically using a complex model that involves surface diffusion and ion motionequations. It is revealed that Ni catalyst patterns of different degrees of order, with Ninanoparticle sizes up to 12.5 nm, exhibit different kinetics of saturation with carbon on theSi surface. It is shown that in the cases examined (surface coverage in the rangeof 1–50%, highly disordered Ni patterns) the relative pattern saturation factorcalculated as the ratio of average incubation times for the processes conducted in theneutral and ionized gas environments reaches 14 and 3.4 for Ni nanoparticles of 2.5and 12.5 nm, respectively. In the highly ordered Ni patterns, the relative patternsaturation factor reaches 3 for nanoparticles of 2.5 nm and 2.1 for nanoparticles of12.5 nm. Thus, more simultaneous saturation of Ni catalyst nanoparticles of sizes inthe range up to 12.5 nm, deposited on the Si substrate, can be achieved in thelow-temperature plasma environment than with the neutral gas-based process.