Photolithography using lateral surface of nanofibers

To enhance the resolution of photolithography, we demonstrate a technique that confines the exposure area by using lateral surface of nanofibers. Due to evanescent wave and optical tunneling effect, the interaction area of optical energy and the photoresist layer is confined into sub-wavelength dimension. Illuminated by a He-Cd laser device with a 442 nm wavelength, exposed lines with sub-wavelength width were obtained by using a nanofiber with a 247 nm diameter. Furthermore, curve lines and annular lines were obtained by manipulating the shape of nanofibers on the photoresist layer.