Fabrication of a submicron patterned electrode using an electrospun single fiber as a shadow-mask

We realize a uniform submicron-gap electrode by using an electrospun single fiber as a shadow-mask. By stretching an electrospun fiber, we can decrease the diameter of the fiber from 2 μm to 564 nm with its standard deviation of 57.7 nm. We place the fiber on the center of a Si/SiO2 substrate followed by the deposition of a molybdenum trioxide adhesion layer and Au electrode. After removing the fiber from the Si/SiO2 substrate, the submicron-gap gold electrode is formed. Characterization of the gap with scanning electron microscope revealed that the gap has a good uniformity; the average gap length is 865 nm throughout 2 mm gap width.