KMLabs, STROBE Science and Technology Center at CU Boulder, and imec's Attolab have worked collaboratively to present the world's first phase-sensitive extreme ultraviolet (EUV) imaging reflectometer.
It combines the excellent phase stability of coherent high-harmonic sources, the unique chemical sensitivity of extreme ultraviolet reflectometry, and state-of-the-art ptychography imaging algorithms. This tabletop microscope can nondestructively probe surface topography, layer thicknesses, and interface quality, as well as dopant concentrations and profiles.
By combining the unique strengths of tabletop, coherent, EUV high-harmonic sources with excellent phase stability and CDI, known imaging science challenges associated with the synthesis and integration of next-generation quantum, semiconductor, and spintronic devices and heterostructures, can be addressed, independent of architecture.
In the future, it will be possible to enhance the chemical/topographic contrast and the spatial resolution (to <10-nm transverse resolution and <1-Å axial precision) by using shorter- or multiwavelength illumination and by imaging the sample at multiple in-plane rotational orientations and/or higher NA. Moreover, by harnessing the femtosecond time resolution of EUV HHG beams, the imaging reflectometer can be enhanced further to capture charge and spin and heat transport in the next-generation devices and link structure to function.
This work represents a fundamentally new and useful approach for imaging nanostructures and nanomaterials that has unique advantages compared to complementary techniques such as electron, atomic force, and other scanning probe microscopes.
The paper was published on Science Advances, Vol. 7, No. 5, on January 27, 2021.