Fabrication of nanosize aperture under electron beam exposure for optical trapping device

Recently there have been tremendous interests about single molecule trapping and characterization using nearfield optical technique. In order to manipulate and trap single molecule such as DNA, the trapping volume has to be significantly smaller than the normal optical trapping with laser beam. The evanescent field can provide the tiny trapping volume and can successfully trap single molecules. The nanosize metal aperture array has been designed and fabricated using various semiconductor fabrication techniques.