X-ray holographic microscopy using photoresists

Abstract

Gabor x-ray holograms of biological specimens and of test objects that display <56-nm resolution are presented. This spatial resolution is more than an order of magnitude smaller than what has been achieved previously in x-ray holography. The holograms were recorded on photoresist using 2.57-nm soft x rays from the X-17t undulator at the National Syncrotron Light Source at Brookhaven National Laboratory. The processed photoresists were enlarged with an electron microscope and digitized using a scanning microdensitometer; the digitized holograms were reconstructed numerically. The exposure requirements were in good agreement with simple theory. The method offers promise as a technique for soft-x-ray microscopy.

Holographic imaging with a nanometer resolution using compact table-top EUV laser

“…The obtained resolution exceeds by~19-21 nm the best possible obtainable resolution of 27 nm set by l 2NA [10]. Several factors degrade the resolution.…”

“…Gabor holography with an early X−ray laser pumped by two beams of the fusion−class NOVA laser at Law− rence Livermore National Laboratory demonstrated a spatial resolution of 5 μm [9]. Other experiments utilized synchrotron light to image biological samples, nano structures, and magnetic domains [10][11][12]. Lens−less diffractive imaging based on iterative phase retrieval following the proposal by Sayre [13] has demonstrated soft X−ray imaging with 50−nm spatial resolu− tion utilizing l = 1.5 nm source [14].…”

Two and Three Dimensional Extreme Ultraviolet Holographic Imaging with a Nanometer Spatial Resolution

“…Gabor holography with an early X-ray laser pumped by two beams of the fusion-class NOVA laser at Lawrence Livermore National Laboratory demonstrated a spatial resolution of 5 m (Trebes et al, 1987). Other experiments utilized synchrotron light to image biological samples, nano structures, and magnetic domains (Jacobsen et al, 1990;Lindas et al, 1996;McNulty et al, 1992). Lensless diffractive imaging, based on iterative phase retrieval, following the proposal by Sayre, (Sayre et al, 1998) have demonstrated SXR imaging with 50 nm spatial resolution utilizing = 1.5 nm source (Elsebitt et al, 2004).…”

Aspects of nanometer scale imaging with extreme ultraviolet (EUV) laboratory sources

“…The first demonstration of holographic recording using a EUV/SXR laser was performed in Lawrence Livermore National Lab, using the NOVA laser facility [3]. Some early experiments also utilized large facilities synchrotron light to image biological samples, nano structures, and magnetic domains [4,5]. The first demonstration of holo− graphic imaging using a table−top source achieved 7−μm spatial resolution with a high harmonic (HHG) source [6].…”