ETRI develops ultra-high-density micro-LED display technology for AI and XR

South Korean researchers achieve 2,500 PPI bonding density surpassing HBM4 in integration, with technology already transferred to domestic industry

ETRI researchers demonstrate a 2,500 PPI ultra-high-density micro-LED display. [ETRI]

South Korean researchers have secured a key technology for ultra-high-resolution displays designed for AI and XR applications.

The Electronics and Telecommunications Research Institute (ETRI) said it has developed a 2,500 PPI ultra-high-density LEDOS display technology — regarded as a core display platform for the AI and XR era — along with an ultra-high-density laser simultaneous transfer and bonding process capable of stably joining approximately 920,000 bumps at a 10-micrometer pitch.

Using proprietary materials and laser process technology, the researchers achieved an ultra-high-density bonding tighter than that of HBM4, which is widely considered the leading edge of semiconductor packaging. HBM4 operates at roughly a 20-micrometer pitch with around 200,000 bumps — a far lower integration density than what the new ETRI process delivers.

LEDOS is a next-generation micro-display that directly bonds micro-LEDs onto silicon CMOS circuitry.

XR devices such as AR glasses and VR headsets present images at close range to the eye, requiring extremely high-resolution pixels packed into a very small area. LEDOS meets that demand by simultaneously delivering ultra-high resolution, ultra-high brightness and low power consumption.

A SITRAB-based 2,500 PPI ultra-high-density micro-LED display. [ETRI]

The technology is particularly valued as a core display platform for the AI and XR era, offering sharp visuals even in bright outdoor environments while keeping power consumption low.

ETRI has transferred the technology to a domestic materials company, and the related process equipment is being validated in actual manufacturing environments at a domestic semiconductor back-end specialist's mass production line. The significance, researchers say, lies in moving beyond the laboratory stage to demonstrate real industrial applicability by linking the technology to the domestic materials, equipment and packaging ecosystem.

"This achievement shows that we can realize ultra-high-density bonding surpassing HBM4 using only ETRI's own materials and process technology, without relying on expensive overseas processes," said Choi Kwang-seong, head of ETRI's Creative Source Research Division. "Going forward, the technology can be expanded into AR glasses, VR headsets, ultra-compact displays for defense and medical use, and advanced semiconductor packaging."

The research was presented at SID Display Week 2026, the world's largest display conference, where it received the People's Choice Award in the micro-LED category.

nbgkoo@heraldcorp.com