Cutting and Welding of Nanomaterials with an Electron Beam

Results Scanning tunneling microscope and atomic force microscope have been applied to manipulate individual atoms or clusters on a clean surface.Focused ion beam technique is routinely used to cut materials down to sub-100 nm dimension.However,in between the atomic and the sub-100 nm scales,i.e.,at the nanometer scale,to date there is no well-established physical modification technique.Here we demonstrate that localized,impurity-free nano-welding and nano-cutting techniques with a high-intensity electron beam (HIEM) have a great potential for the fabrication of nanodevices.It is known that an intense electron beam causes various inelastic scattering processes in a target specimen that create heating,amorphization,ablation effects,and,when the intensity is high enough,some nonlinear effects such as plasma formation at the specimen surface.We will show that a HIEB with an intensity of 106 A/cm2 can be applied to create holes,gaps,and other patterns of nanometer dimensions on a single semiconducting or metallic nanowire[1].In particular,the hole-formation process on silicon nanowires under a HIEM will be discussed in detail.We will also show that an electron beam with slightly weaker intensities can be used to weld individual nanowires,forming metal-to-metal or metal-to-semiconductor nanowire junctions.This can be applied to reduce contact resistance between metallic nanowires and leads[2],and,e.g.,to fabricate nano-scale thermal couples.中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)57174