Swiss additive manufacturing startup Scrona and Avantama, developer and manufacturer of high-tech materials for electronics, have jointly announced that they have successfully processed high-performance perovskite quantum dot (QD) ink using Scrona's electrohydrodynamic (EHD) inkjet printing.
This collaboration combines the benefits of the inkjet process with high-patterning resolution to drive a new generation of efficient and cost effective MicroLED displays, while also increasing color purity and brightness, and improving overall pixel production tact time.
CEO and co-founder of Scrona, Patrick Galliker, sees the inkjet process being used to apply the color filters on quantum dots built with photolithography on a silicon wafer before they are moved onto a display panel. Applying the color filters to create a full color display with spin coating is a major challenge at the moment, and this is where inkjet printing, or additive manufacturing, can prove useful - but only if it is fast enough.
"We continue to find new applications of EHD that will meet the demands of the industry by offering an additive, completely waste-free process with higher resolution capabilities than lithography patterning," said Dr. Galliker. "While conventional inkjet printheads require inks of low viscosity, Scona has already demonstrated printing inks 1,000 times what they can process, paving the way for a much more efficient generation of MicroLED displays."
Avantama's perovskite QDs were said in the statement to have the highest absorption coefficients among QDs, which allows for thinner pixels with good optical density. Perovskite QDs also have the highest weight-based absorption compared to others QDs, and this directly translates to very high OD/thickness values.
"Conventional inkjet printing is not a viable option for emerging MicroLED displays because they use much smaller pixels than QD-OLED displays," said Dr. Norman Lüchinger, co-founder and CTO at Avantama. "By partnering with Scrona, we have been able to demonstrate that an OD greater than 1 can be obtained with a perovskite QD layer thickness below 2µm. This can reduce the printhead nozzle count by a factor of five and deliver a thin QD layer that improves the overall efficiency and production tact time of MicroLED display technology."