Department of Electrical Engineering, Pennsylvania State University, University Park 16802, United States of America.
Nanotechnology. 2019 Mar 1;30(9):095502. doi: 10.1088/1361-6528/aaf48e. Epub 2018 Nov 28.
We investigate the current transport characteristics in the electrolyte-dielectric-electrolyte structure commonly used in the in situ controlled breakdown (CBD) fabrication of solid-state nanopores. It is found that the stochastic breakdown process could lead to fidelity issues of false positives (an incorrect indication of a true nanopore formation) and false negatives (inability to detect initial nanopore formation). Robust and deterministic detection of initial physical breakdown to alleviate false positives and false negatives is critical for precise nanopore size control. To this end, we report a high fidelity moving Z-score method based CBD fabrication of solid-state nanopore. We demonstrate 100% success rate of realizing the initial nanopore conductance of 3 ± 1 nS (corresponds to size of 1.7 ± 0.6 nm) regardless of the dielectric membrane characteristics. Our study also elucidates the Joule heating is the dominant mechanism for electric field-based nanopore enlargement. Single DNA molecule sensing using nanopores fabricated by this method was successfully demonstrated. We anticipate the moving Z-score based CBD method could enable broader access to the solid state nanopore-based single molecule analysis.
我们研究了常用于原位控制击穿 (CBD) 制造固态纳米孔的电解质-介电-电解质结构中的电流传输特性。研究发现,随机击穿过程可能导致假阳性(错误指示真正的纳米孔形成)和假阴性(无法检测初始纳米孔形成)的准确性问题。稳健且可确定地检测初始物理击穿以减轻假阳性和假阴性对于精确的纳米孔尺寸控制至关重要。为此,我们报告了一种基于高保真度移动 Z 分数的 CBD 制造固态纳米孔的方法。我们展示了 100%的成功率,实现了初始纳米孔电导为 3 ± 1 nS(对应于 1.7 ± 0.6 nm 的尺寸),无论介电膜特性如何。我们的研究还阐明了焦耳加热是基于电场的纳米孔扩大的主要机制。使用通过这种方法制造的纳米孔进行的单个 DNA 分子传感也得到了成功验证。我们预计基于移动 Z 分数的 CBD 方法将能够更广泛地应用于基于固态纳米孔的单分子分析。