A joint research team from KAIST, Korea University, and the University of Hong Kong has developed 3D printing technology that allows the creation of ultra-small infrared sensors measuring less than 10μm at room temperature. Infrared sensors detect light in a range not visible to the human eye and convert it into electrical signals, making them pivotal in environments with low visibility, such as during the night or in smoke and fog. These sensors are crucial for technologies like autonomous vehicle cameras, IoT sensors, and robots.
Traditional manufacturing methods based on semiconductor processes require high temperatures, limiting material selection and leading to high energy consumption. The team developed a precision 3D printing process that utilizes metal, semiconductor, and insulator materials as liquid inks in a nanocrystal form, which are then layered. This process enables the production of infrared sensors in the desired shape and size at room temperature.
The researchers implemented a technique called “ligand exchange,” which replaces the insulating molecules on nanoparticle surfaces with conductive ones, thus achieving excellent electrical performance without the need for high-temperature processing. This advancement successfully created sensors smaller than 10μm, about a tenth the width of a human hair.
Professor Kim Ji-tae highlighted that this new technique reduces the immense energy consumption associated with high-temperature processes, contributing to cost reduction and environmentally friendly manufacturing. The findings were published in the online edition of the prestigious international journal “Nature Communications” on October 16.