Formation of nanopores in a SiN/SiO ₂ membrane with an electron beam

Abstract

An electron beam can drill nanopores in Si O2 or silicon nitride membranes and shrink a pore to a smaller diameter. Such nanopores are promising for single molecule detection. The pore formation in a 40 nm thick silicon nitride Si O2 bilayer using an electron beam with a diameter of 8 nm (full width of half height) was investigated by electron energy loss spectroscopy with silicon nitride facing toward and away from the source. The O loss shows almost linear-independent of which layer faces the source, while N loss is quite complicated. After the formation of a pore, the membrane presents a wedge shape over a 70 nm radius around the nanopore. © 2005 American Institute of Physics.