David Gerrold, a prolific American author, and screenwriter, summarizes the progress of the last 120 years when he observes, “In the 20th century, we had a century where at the beginning of the century, most of the world was agricultural and industry was very primitive. At the end of that century, we had men in orbit, we had been to the moon, we had people with cell phones and color televisions and the Internet and amazing medical technology of all kinds.”
The meteoric acceleration of “amazing medical technology of all kinds” continues today, and the laboratories at NIST, the National Institute of Standards and Technology, are significant players in this progress.
The benefits of NIST’s technology research come to the marketplace when businesses license NIST’s patents, and this article introduces three biomedical technologies in the field of phase-contrast X-ray imaging that are available for licensing.
These patents are the product of more than two decades of research in electrodeposition by Daniel Josell and Thomas P. Moffat of the Functional Nanostructured Materials Group in the Materials Science and Engineering Division of NIST’s Material Measurement Laboratory.
X-ray technology has always been adept at imaging bones, but imaging soft tissue is more complicated. The overall issue addressed by these inventions is the improvement of X-ray phase contrast imaging technologies for soft tissue imaging without the injection of contrast agents.
The first of the technologies available for licensing is a chemistry that improves gold filling of features recessed into substrate surfaces, including, but not limited to, features in gratings used in phase contrast imaging. Drs. Moffat and Josell invented a method to fill features patterned into the surfaces of conducting substrates, or substrates such as silicon wafers with metalized surfaces, using chemistry to fill upward from the feature bottoms with fully dense, void-free gold deposits. Their technology, which also halts filling automatically upon the completion of feature filling, yields uniform fill across the entire patterned substrate with minimal waste of gold. The electrolyte includes no toxic heavy metals like lead or thallium or polymer additives. The electrolyte is also non-cyanide and near-neutral, and deposition is conducted at room temperature. Check out the summary of Patent 10,889,908, “Bottom-up gold electrodeposition for high aspect ratio features in imaging applications.”
The next technology, “Void-free metallic diffraction gratings for enhanced X-ray interferometry imaging,” furthers the previous research by detailing gratings with void-free, gold-filled high aspect ratio features fabricated using the bottom-up gold-filling chemistry. These gratings include arrays of very narrow and very deep trenches etched into silicon wafer surfaces and then bottom-up filled with gold using the patented chemistry, including gratings with trenches more than 60 times as tall as their 1-micrometer width. Alternate technology for void-free gold fill is limited to soft polymeric substrates with comparatively coarse features and involves costly patterning at a synchrotron light source. Full details can be found in Patent 11,579,344; this technology is summarized here.
The latest invention in this research series is in Patent Application 17/972,816, “Process for void-free metallic diffraction gratings for enhanced X-ray interferometry imaging.” It builds on the advances of the other two patents, providing details on processes for a void-free gold fill of gratings having high aspect ratio features using the patented chemistry, as seen here. The patent application has been granted, with the patent expected to be issued in July 2023.
These exceptional and attractive cutting-edge technologies are prime candidates for licensing. For more specifics, contact Dr. Daniel Josell at daniel.josell [at] nist.gov () or NIST’s Technology Partnerships Office at TPO [at] NIST.GOV.