One Day’s Work in an Hour: A Versatile, Fast-scanning, X-ray Microscope

The Science

Scientists have developed a high-speed, low-maintenance X-ray microscope that achieves images with less than 10-nanometer resolution. Much like an optical microscope, it forms detailed pictures of a sample. However, it uses X-rays instead of visible light to reveal extremely small structures in a sample's interior. This versatile system can produce a full 3D image in about an hour. This task once took a full day. It works with two-dimensional multilayer Laue lenses, which were previously developed by scientists with support from the Department of Energy's Office of Science. It also incorporates cutting-edge components such as advanced sensors and fast data-processing units.

The Impact

Recent advances in X-ray focusing have made imaging resolution possible at the nanometer scale. However, that precision usually comes at a cost. It results in massive data sets, long scanning times, and the risk of radiation damage. Radiation damage is a particular concern when examining large, delicate samples such as microelectronic chips and integrated circuits. The new microscope overcomes these hurdles by cutting data-acquisition times and boosting efficiency by more than a factor of ten. Its innovative design combines state-of-the-art technology with a maintenance-friendly framework. It also works with a variety of nano-focusing optics. This advance sets the stage for the next generation of high-resolution X-ray microscopes.

Summary

Large-area samples with tiny features-like microelectronic chips and integrated circuits-are difficult to image. Their 3D X-ray scans must be both fast and extremely high in resolution. To meet this challenge, a team at the National Synchrotron Light Source (NSLS-II), a DOE Office of Science User Facility, built a next-generation X-ray microscope. This microscope can precisely manipulate and align the unique one-dimensional and two-dimensional multilayer Laue lenses needed for nano-scale imaging. The system uses line-focusing interferometry as a real-time position encoder during "fly-scanning." This approach allows it to track a moving sample with exceptional accuracy. Its new scanning control hardware and software integrate seamlessly with the Experimental Physics and Industrial Control System (EPICS). This control system enables fully automated operation. This design delivers a detector-limited acquisition rate of 1.25 kHz-about 20 times faster than current NSLS-II microscopes. It can also be pushed to 10 kHz or more with faster detectors and higher photon flux. Initial tests achieved a sample-limited resolution of roughly 6 nm in 2D and under 20 nm in 3D on a microelectronics specimen. As it is highly adaptable, the platform lays the groundwork for the next generation of scanning X-ray microscopes across DOE Office of Science facilities.

Contact

Evgeny Nazaretski
National Synchrotron Light Source II
Brookhaven National Laboratory
[email protected]

Funding

This work was partially carried out at the Center for Functional Nanomaterials and the National Synchrotron Light Source II, both of which are DOE Office of Science User Facilities. This work was also performed in part at the Advanced Science Research Center Nano Fabrication Facility of the Graduate Center at the City University of New York.

Publications

Xu, Weihe, et al. A versatile high-speed x-ray microscope for sub-10 nm imaging. Rev. Sci. Instrum. 95 (11), 113705 (2024) [DOI: https://doi.org/10.1063/5.0225904]