Groundbreaking work by scientists from Switzerland, Finland and Germany has lead to a new world record in X-ray microscopy. For the first time ever, features below 10 nm in width were resolved.
Key to this new world record was doubling of the effective line density of FZP template (Fresnel Zone Plate, a key component of an X-ray microscope) by extremely conformal thin films created through the use of Atomic Layer Deposition (ALD). ALD work was carried out with a Picosun Sunale reactor at the premises of the University of Helsinki’s Laboratory of Inorganic Chemistry.
ALD is a thin film method which enables completely controlled growth of extremely conformal films through its signature self-limiting, sequential surface reactions. ALD produces complex layer structures with atomic level accuracy. ALD processes can be reproduced with stunning accuracy.
The group produced a modified FZP with structures based on the conformal deposition of high refractive index material by ALD onto the sidewalls of a pre-patterned template made from a low refractive index material. This new focusing structure achieves an unprecedented spatial resolution in X-ray microscopy. Line widths of down to 9 nm were successfully resolved.
Vila-Comamala J., Jefimovs K., Raabe J., Pilvi T., Fink R.H., Senoner M., Maassdorf A., Ritala M., David C.: Advanced thin film technology for ultrahigh resolution X.ray microscopy. Ultramicroscopy. 2009 Oct;109(11):1360-4. Epub 2009 Jul 15.