New photonic sintering method promises big gains

Engineers at Oregon State University (OSU) say they have made a breakthrough in photonic sintering that has implications for technologies such as embedded electronics, solar cells and biomedical sensors.

Xenon lamp

Photonic sintering is used to fuse nanoparticles together to form a thin functional film. In the new research, published in Scientific Reports, the OSU team claim they have dramatically improved on previous methods, creating high quality products at much lower temperatures, at least twice as fast and with 10 times more energy efficiency.

“Photonic sintering is one way to deposit nanoparticles in a controlled way and then join them together, and it’s been of significant interest,” said Rajiv Malhotra, an assistant professor of mechanical engineering in the OSU College of Engineering.

“Until now, however, we didn’t really understand the underlying physics of what was going on. It was thought, for instance, that temperature change and the degree of fusion weren’t related – but in fact that matters a lot.”

According to the researchers, the new process only requires the light from a xenon lamp, which can be used over comparatively large areas, and is much faster than conventional thermal methods. Operating at lower temperatures means that the process can be used on materials such as paper that would otherwise burn. This, in turn, opens up the possibility of incorporating nanotechnology into a range of cheaper substrates, as well as improved efficiency for higher-end electronics such as biomedical sensors and photovoltaic cells.

“Lower temperature is a real key,” said Malhotra. “To lower costs, we want to print these nanotech products on things like paper and plastic, which would burn or melt at higher temperatures. We now know that is possible, and how to do it. We should be able to create production processes that are both fast and cheap, without a loss of quality.”

Other potential uses include gas sensors, radiofrequency identification tags and flexible electronics. As part of the path to commercial production, the OSU team is working with two private sector manufacturers to create a proof-of-concept facility in the laboratory.