Department of Material Science and Engineering, University of Tennessee, Knoxville, TN 37996-2200, USA.
Nanotechnology. 2013 Mar 22;24(11):115302. doi: 10.1088/0957-4484/24/11/115302. Epub 2013 Feb 28.
The ion beam induced nanoscale synthesis of PtCx (where x ∼ 5) using the trimethyl (methylcyclopentadienyl)platinum(IV) (MeCpPt(IV)Me3) precursor is investigated by performing Monte Carlo simulations of helium and neon ions. The helium beam leads to more lateral growth relative to the neon beam because of its larger interaction volume. The lateral growth of the nanopillars is dominated by molecules deposited via secondary electrons in both the simulations. Notably, the helium pillars are dominated by SE-I electrons whereas the neon pillars are dominated by SE-II electrons. Using a low precursor residence time of 70 μs, resulting in an equilibrium coverage of ∼4%, the neon simulation has a lower deposition efficiency (3.5%) compared to that of the helium simulation (6.5%). At larger residence time (10 ms) and consequently larger equilibrium coverage (85%) the deposition efficiencies of helium and neon increased to 49% and 21%, respectively; which is dominated by increased lateral growth rates leading to broader pillars. The nanoscale growth is further studied by varying the ion beam diameter at 10 ms precursor residence time. The study shows that total SE yield decreases with increasing beam diameters for both the ion types. However, helium has the larger SE yield as compared to that of neon in both the low and high precursor residence time, and thus pillars are wider in all the simulations studied.
使用三甲基（甲基环戊二烯基）铂（IV）（MeCpPt（IV）Me3）前体，通过氦和氖离子的蒙特卡罗模拟研究了离子束诱导的 PtCx（其中 x∼5）纳米尺度合成。由于氦离子的相互作用体积较大，因此与氖离子相比，氦离子束导致更多的横向生长。在这两种模拟中，通过二次电子沉积的分子主导着纳米柱的横向生长。值得注意的是，氦柱主要由 SE-I 电子主导，而氖柱主要由 SE-II 电子主导。使用 70μs 的低前体停留时间，导致平衡覆盖率约为 4%，与氦模拟（6.5%）相比，氖模拟的沉积效率（3.5%）较低。在前体停留时间较大（10ms），因此平衡覆盖率较大（85%）时，氦和氖的沉积效率分别增加到 49%和 21%；这主要是由于横向生长速率增加导致支柱变宽。通过在 10ms 前体停留时间下改变离子束直径进一步研究了纳米级生长。研究表明，对于两种离子类型，总 SE 产率都随束直径的增加而降低。然而，在低和高前体停留时间下，氦的 SE 产率都大于氖，因此在所有研究的模拟中支柱都更宽。
