Practical guide for in-house solid-state nanopore fabrication and characterization

Solid-state nanopores are considered a better alternative to biological nanopores for several sensing applications due to their better chemical, mechanical, and temperature stability. In addition to sequencing, nanopores currently also find applications in education, biomarker identification, quantification, single-molecule chemistry, and DNA computing. Nanopore technology's simplicity and wide interdisciplinary applications have raised further interest among industry and scientific community worldwide. However, further development in solid-state nanopore technology and exploring its applications presents the need to have the capability to fabricate them in-house. This will be a more financially viable and flexible approach, especially in resource-limited situations. In order to do an in-house fabrication of solid-state nanopores, two key steps are involved. The first step is to fabricate suspended thin films, and the second one is the drilling of pores in these suspended thin membranes. Successful implementation of these two steps involves tedious optimization and characterization of the fabricated chips and nanopores. In this work, we describe the nanopore fabrication process in a ready-to-follow step-by-step guide and present solutions for several practical difficulties faced during the silicon nitride pore fabrication process. This work will help anyone new to this field and make the pore fabrication process more accessible.