Fabrication and characterization of silicon nitride nanopore

Nanopores have become an important tool for molecule detection at single molecular level. In our work, the solid nanopore in silicon nitride membranes are fabricated and characterized by experiments. Firstly, the free-standing silicon nitride membranes are designed and etched by delicate techniques. Then, the free-standing membranes are drilled by focus ion beam. A set of nanopores with varied diameters and shapes are fabricated by different acting time of focused ion beam. These nanopores display the high quality of morphologies and electric signals. In addition of DNA, a series of evident block currents appear corresponding to the translocation of single DNA molecule through the pore. The results will shed light on the engineering of nanopore devices for single-molecule sensing.