DELO carries out studies on miniLED dice
DELO has carried out internal feasibility studies, demonstrating the successful electrical and mechanical bonding of miniLED dice using directional conductive adhesives.
The results showed strong, reliable connections and high success rates during illumination testing. These findings highlight how adhesives can enhance the manufacturing process of miniLED displays, making them more suitable for large-scale production, and paving the way for mass microLED display manufacturing.
Currently, the display industry relies heavily on solder materials to interconnect SMD components, but as components like miniLEDs and microLEDs become increasingly smaller, isotropic conductive materials such as solder may struggle to avoid short circuits at this scale. This challenge led DELO Industrial Adhesives, a high-tech manufacturer based in Germany, to explore the feasibility of using their advanced adhesive products as an alternative.
DELO identified their product DELO MONOPOX AC268 as the most suitable material for testing. This adhesive is electrically conductive in one direction, preventing short circuits. Additionally, its processing characteristics allow the use of printing masks without needing to shrink the openings for dispensing, making it well-suited for the application.
In the study, the miniLED dice were dipped into a reservoir of DELO MONOPOX AC268 adhesive and thermally cured at 180°C for 20 seconds. Once cured, the miniLEDs were tested for operational viability. A single die was fixed to a test board, while another board featured multiple lights in a daisy chain arrangement. In both cases, the lights illuminated without any short circuits, demonstrating the adhesive's effectiveness.
“These results prove that, indeed, adhesives are a suitable alternative to pick-and-place soldering for miniLED applications,” said Tim Cloppenborg, Senior Product Manager for LED at DELO. “Having a new, streamlined assembly process opens doors to increased production yields as well as the expedition of newer technologies, like microLEDs, which will enable fascinating new display applications within the next decade.”
This study is one of many efforts by DELO, which conducts over 3,000 customer tests annually across various industries. The company supplies high-performance materials to leading clients, including Infineon and Mercedes-Benz, serving sectors such as automotive, consumer electronics, and semiconductors.