Scalable fabrication of sub-10 nm polymer nanopores for DNA analysis

We present the first fabrication of sub-10 nm nanopores in freestanding polymer membranes via a simple, cost-effective, high-throughput but deterministic fabrication method. Nanopores in the range of 10 nm were initially produced via a single-step nanoimprinting process, which was further reduced to sub-10 nm pores via a post-NIL polymer reflow process. The low shrinkage rate of 2.7 nm/min obtained under the conditions used for the reflow process was the key to achieving sub-10 nm pores with a controllable pore size. The fabricated SU-8 nanopore membranes were successfully employed for transient current measurements during the translocation of DNA molecules through the nanopores.