Deep ultraviolet digital holography for nanoscopic applications

Digital holographic microscopy (DHM) is a promising method for 3D microscopy because of its ability to extract the 3D information of the object by taking only one image and deriving the phase and amplitude information of the object wave-front in any plane [1-3]. By improving nanotechnology, the size of structures and functional devices is decreasing down to the nano-scale which is smaller than the wavelength of the light. The diffraction-limited lateral resolution, introduced by Abbe’s criterion ( NA k / λ ), is a barrier that makes an obstacle for DHM methods to go that deep. To improve the resolution one should increase NA and/or use a shorter wavelength. One approach, to increase NA , is to guide light beams with higher angles to the detector using synthetic aperture techniques, by means of gratings [4] or oblique illumination [5,6]. In this paper we arranged a setup implementing a short wavelength (193 nm) and an objective with high numerical aperture ( 75 . 0 NA = ) and using oblique illumination technique. 2 Experiment