Markwitz A
Institute of Geological and Nuclear Sciences Ltd, Rafter Research Laboratories, 30 Gracefield Road, Lower Hutt, New Zealand.
J Nanosci Nanotechnol. 2001 Dec;1(4):393-6.
Accelerator-based ion implantation can be used to produce stoichiometric ratios beyond thermodynamic equilibrium. In the studies reported here, single crystalline silicon wafer material was implanted with high fluences of nitrogen. The implantations, performed with 15N at 5 keV/ion, resulted in the formation of highly swollen nitrogen rich surfaces that incorporated up to 63 at.% nitrogen. The implanted specimens were subsequently annealed with electron beams at high temperature, typically 1150 degrees C for moderately short periods of time (15 s) to investigate the formation of silicon nanowhiskers. However, it was observed that nanowhiskers, the formation of which can be expected by comparable understoichiometric implantations, did not appear. Although the shallow implantations created ultrathin silicon nitride films with typical thickness of 25 nm, laterally swollen areas of 400 +/- 50 nm were observed with atomic force microscopy operated in supersonic mode.
基于加速器的离子注入可用于产生超出热力学平衡的化学计量比。在本文报道的研究中，用高剂量的氮离子注入单晶硅片材料。使用能量为5 keV/离子的15N进行注入，导致形成高度肿胀的富氮表面，其中氮含量高达63原子%。随后，将注入的样品用电子束在高温下（通常为1150℃，持续较短时间（15秒））进行退火，以研究硅纳米 whiskers 的形成。然而，观察到并未出现通过类似的亚化学计量注入预期会形成的纳米 whiskers。尽管浅注入产生了典型厚度为25 nm的超薄氮化硅薄膜，但在以超音速模式操作的原子力显微镜下观察到横向肿胀区域为400±50 nm。
