Characterization of ITO-SiNx Nanopores for Single-Biomolecular Sensing

Nanopores incorporating electrical gates made of ITO material have highly-desired potential of electrically modulating the translocation process of biomolecules. In this work, we report our experimental study of such devices under the condition of no electrical gate biases being applied. This baseline characterization is to demonstrate their suitability for translocation sensing. The nanopore devices incorporating ITO gate electrodes are fabricated by TEM drilling, yielding ~10 nm pore sizes. dsDNA translocation experiments, as well as noise characterization, are conducted using these devices and compared with bare SiN
_x
nanopore control devices. We particularly examine the individual signals and statistics of the folding and knotting configurations of translocating dsDNAs. It is demonstrated that, without applying gate biases, the incorporated ITO layers only have moderate effects on the dsDNA translocation process, suggesting their general suitability for translocation sensing.