Flexible MicroLED

Researchers from the University of Waterloo have demonstrated the successful integration of a-Si:H TFTs and high-efficiency micro-LED chips on large-area flexible substrates. This is the first time that an amorphous silicon was used to drive Micro-LEDs which could pave the way for lower-cost micro-LED display fabrication using existing LCD technology.

the researchers use a 2-TFT pixel circuit, with blue GaN-based micro-LED chips. The low-temperature TFT production process enabled the direct integration onto a flexible flexible polyethylene naphthalate (PEN) substrate. After the TFT fabrication, the micro-LED chips were flip-chip bonded on the TFT, and then transferred onto the flexible pixel circuit using a selective laser lift-off process.

Researchers from Korea's KAIST developed flexible vertical micro-LEDs (f-VLEDs) using anisotropic conductive film (ACF)-based transfer and interconnection technology.

The researchers developed their own transfer equipment and used it to fabricate a 50x50 array of f-VLEDs using simultaneous transfer and interconnection through the precise alignment of ACF bonding process. The researchers report that the micro-LEDs achieved an optical power density of 30 mW/mm2 - which is three times higher than that of lateral micro LEDs. The LEDs offer improving thermal reliability and lifetime by reducing heat generation within the thin film LEDs.