Fabrication and characterization of nanopore sandwich devices for DNA kinetic proofreading studies

It has been proposed [1] that solid-state nanopores can be used as a kinetic proofreading mechanism for oligonucleotide hybridization on ssDNA molecules. We describe the first generation of nanopore sandwich structures consisted of two nanopores of different thicknesses of Si$_{3}$N$_{4}$ separated by a SiO$_{2}$ cavity. We will discuss the results of helium ion-beam and Ga FIB drilling and TEM characterization of the nanopore sandwiches devices. This work was supported by the National 1000-People Plan of China and Jiangsu-985 Fund, and NSFC grant no.51302037. [1] X.S. Ling, ``Methods of sequencing nucleic acids using nanopores and active kinetic proofreading'', WO/2013/119784, International Application No.: PCT/US2013/025106.