Fernández-Pacheco A, De Teresa J M, Córdoba R, Ibarra M R
Instituto de Nanociencia de Aragón, Universidad de Zaragoza, Zaragoza, 50009, Spain. Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, Facultad de Ciencias, Zaragoza, 50009, Spain.
Nanotechnology. 2008 Oct 15;19(41):415302. doi: 10.1088/0957-4484/19/41/415302. Epub 2008 Sep 3.
A novel technique to establish atomic-sized contacts in metallic materials is shown. It is based on etching a (sub)micrometric electrode via a low-energy focused ion beam. The in situ measurements of the nanoconstriction resistance during the etching process permit control of the formation of atomic-sized constrictions with milling time, observing steps in the conductance in the range of the conductance quantum (G(0) = 2e(2)/h), just before entering the tunnelling regime. These constrictions are highly stable with time due to the adherence to a substrate, which allows further studies such as the detailed current-voltage transport investigation reported here. Scanning electron microscopy images are used to correlate the etching process and the constriction microstructure. The high control achieved in the process makes us suggest this technique as a promising route to study physical phenomena in the verge of the metal-tunnel conduction crossover.
展示了一种在金属材料中建立原子尺寸接触的新技术。它基于通过低能聚焦离子束蚀刻（亚）微米级电极。蚀刻过程中纳米缩颈电阻的原位测量允许通过铣削时间控制原子尺寸缩颈的形成，在进入隧穿 regime 之前，观察到电导率量子范围内（G(0) = 2e(2)/h）的电导台阶。由于与衬底的附着，这些缩颈随时间高度稳定，这使得能够进行进一步的研究，例如此处报道的详细电流 - 电压输运研究。扫描电子显微镜图像用于关联蚀刻过程和缩颈微观结构。该过程中实现的高度控制使我们建议将此技术作为研究金属 - 隧道传导交叉边缘物理现象的一条有前途的途径。
