Nov 03, 2025

Room temperature 3D printing unlocks microscale infrared sensors at lower costs

New room-temp 3D printing makes microscale infrared sensors customizable and energy-efficient, reducing production costs and expanding design options.

(Nanowerk News) A new 3D printing method could change how infrared sensors are built and used. These devices, sometimes called “electronic eyes,” detect invisible infrared signals and are vital to technologies like LiDAR for self-driving cars, 3D face recognition in smartphones, and wearable medical devices.

There’s growing demand for smaller, lighter, and more adaptable sensors, but traditional semiconductor manufacturing struggles to keep up. It relies on high heat, rigid processes, and limited materials.

A team led by Professor Ji Tae Kim at KAIST has developed a way to print ultra-small infrared sensors in any shape or size at room temperature (Nature Communications, "Ligand-exchange-assisted printing of colloidal nanocrystals to enable all-printed sub-micron optoelectronics").

3D printing of infrared sensors. a Room-temperature printing process for the electrodes and photoactive layer that make up the infrared sensor. b Structure and chemical composition of the printed infrared microsensor. c Printed infrared sensor micropixel array. (Image: KAIST) (click on image to enlarge)

The sensors are less than 10 micrometers thick, which is slimmer than one-tenth the diameter of a human hair. The method uses inks made of nanocrystals of metals, semiconductors, and insulators. These are stacked layer by layer inside a single 3D printer, creating a complete sensor in one build instead of several complex steps.

A common challenge in printed electronics is that they usually need high heat to reach peak performance. This team avoided that by applying a “ligand-exchange” process, which swaps out insulating molecules on the surface of nanoparticles for ones that conduct electricity. This eliminates the need for high-temperature treatment and saves energy.

“The developed 3D printing technology not only advances the miniaturization and lightweight design of infrared sensors but also paves the way for the creation of innovative new form-factor products that were previously unimaginable,” said Professor Kim. “Moreover, by reducing the massive energy consumption associated with high-temperature processes, this approach can lower production costs and enable eco-friendly manufacturing—contributing to the sustainable development of the infrared sensor industry.”

Source: Korea Advanced Institute of Science and Technology (Note: Content may be edited for style and length)