Rapid Nanomanufacturing of Metallic Break Junctions Using Focused Ion Beam Scratching and Electromigration
Rapid Nanomanufacturing of Metallic Break Junctions Using Focused Ion Beam Scratching and Electromigration
复制标题
DOI：
10.1115/1.4001664
复制
发表时间：
2010-06-01
影响因子：
4
通讯作者：
Iqbal, Samir M.
中科院分区：
文献类型：
--
作者：
Asghar, Waseem;Ramachandran, Priyanka P.;Iqbal, Samir M.
断裂连接提供了一种直接的方式来询问分子的电输运性质，在追求分子电子器件。许多方法用于制造断裂结，包括光学/电子束光刻、电迁移、悬浮导电电极/带的机械控制以及导电材料和纳米线的电化学沉积。所有的方法要么需要连续和缓慢的电子束写入纳米间隙，或遭受低产量的纳米间隙电极装置。在这里，我们报告使用聚焦离子束（FIB）的“划痕”，并从3 μ m宽的线去除一层薄薄的金。划痕导致金属线变薄，并且随后的电流驱动的电迁移导致在精确位置处进入纳米间隙，具有高的器件成品率。将FIB刮擦与电迁移相结合提供了一种在精确位置处产生纳米级断裂结并且具有非常窄的纳米间隙尺寸分布的优雅方法。在FIB划痕之前和之后以及在形成断裂之后使用探针台进行电流-电压测量。大多数间隙落在200-300 nm范围内，并显示出可忽略的电导率。该方法提供了一种新型的、快速的、高通量的断裂结制造方法，其可用于分子传感。[DOI 10.1115/1.4001664]
Break junctions provide a direct way to interrogate electrical transport properties of molecules, in pursuit of molecular electronics devices. A number of approaches are used for the fabrication of break junctions, including optical/e-beam lithography, electromigration, mechanical control of suspended conductive electrodes/strips, and electrochemical deposition of conductive material and nanowires. All approaches either require serial and slow e-beam writing of nanoscale gaps or suffer from low-yield of nanogap electrode devices. Here, we report the use of focused ion beam (FIB) to "scratch" and remove a thin layer of gold from 3 mu m wide lines. The scratch results in thinning of the metal line and subsequent current-driven electromigration results into nanogaps at precise locations with high yield of devices. Combining FIB scratching with electromigration provides an elegant approach of creating nanoscale break junctions at an exact location and with a very narrow distribution of the nanogap sizes. Current-voltage measurements are done using a probe station before and after FIB scratch, and after the breaks were formed. Most of the gaps fall within 200-300 nm range and show negligible conductivity. The approach provides a novel, rapid, and high-throughput manufacturing approach of break junction fabrication that can be used for molecular sensing. [DOI: 10.1115/1.4001664]