Nano-imaging with compact extreme ultraviolet laser sources

Abstract

We report high resolution imaging results obtained utilizing small-scale extreme ultraviolet laser sources. A compact capillary-discharge pumped Ne-like Ar laser emitting at a wavelength of 46.9 nm was used to demonstrate imaging with nanometer-scale resolution in transmission and reflection modes. We exploited the large photon fluence of this short wavelength laser to obtain high-resolution images with exposure times as short as 1 -10 seconds. Images with a spatial resolution better than 140 nm were obtained using the combination of a Sc/Si multilayer coated Schwarzschild condenser and free-standing objective zone plate. Preliminary results of imaging with a 13.9 nm extreme ultraviolet laser light are also discussed.

EUV imaging with a 13nm tabletop laser reaches sub-38nm spatial resolution

“…These two laser lines were selected due to their proximity to the peak reflectance wavelength of 13.5 nm of a typical Mo/Si multilayer coating. Last year we reported our earliest imaging results obtained with 13.9 nm wavelength illumination [22]. In these proceedings we concentrate on data obtained using the λ = 13.2 nm line.…”

“…In addition to the experiments conducted at synchrotron facilities, a variety of imaging experiments have been carried out using both coherent and incoherent short wavelength sources [3][4][5][6][7][8][9][10][11]. In the last several years, smaller-scale short wavelength sources, including high order harmonics [5,6], extreme ultraviolet lasers [7][8][9], and incoherent laser-plasma-based sources [10,11], have been used for submicron resolution imaging. Of these experiments the best performance in terms of spatial resolution, reported as sub-100 nm, has been obtained with an incoherent laser-created plasma source emitting at λ = 3.37 nm in a 2π steradian angle [11].…”

Reflection mode imaging with nanoscale resolution using a compact extreme ultraviolet laser

“…An accurate determination of the microscope's spatial resolution in reflection mode requires imaging of smaller periodic structures with high reflection contrast that were not available at the time of the experiment. However, the spatial resolution of the same instrument in transmission mode was estimated to be in the 120-150 nm range [7]. We expect that the reflection mode resolution is similar.…”

“…More compact sources, such as high order harmonic EUV sources [3,4] and laser plasma-based soft x-ray sources [5,6] have demonstrated the ability to resolve feature sizes below 1 μm. The best resolution obtained to our knowledge with a table-top EUV transmission microscope, ~ 120-150 nm, was recently demonstrated using a compact EUV laser as the illumination source [7]. In reflection mode, however, only a few experiments have been reported.…”

High Repetition Rate Collisional Soft X-Ray Lasers Based on Grazing Incidence Pumping

“…High average power soft X-ray laser operation was first achieved at 46.9 nm using capillary discharge excitation of a Ne-like Ar plasma at repetition rates up to 10 Hz [5]. Capillary discharge pumping allowed the utilization of small-scale high repetition rate soft X-ray lasers in numerous applications, including the determination of optical constants by reflectometry, material ablation studies, plasma interferometry, the characterization of soft X-ray optical components [6], high resolution imaging [7], and nanopatterning [8]. Saturated operation at 10-Hz repetition rate in the 41.8-nm line of Pd-like Xe [9], and in the 32.8-nm line of Ni-like Kr [10] was also reported to occur following collisional excitation in plasmas created by optical field ionization.…”