Monolithic Thin Film Red LED Active-Matrix Micro-Display by Flip-Chip Technology

摘要

A monolithic thin film red light emitting diode (LED) active-matrix (AM) micro-display driven by a complementary metal-oxide semiconductor (CMOS) driver is demonstrated. The resolution of the micro-display is 64 x 36, with a 40 mu m x 40 mu m pixel pitch. Starting from AlGaInP epilayers grown on GaAs substrates, the monolithic red LED array was fabricated and then integrated with the AM driver using Au/In flip-chip bonding technology. After removal of the GaAs substrate, a crack-free thin film micro-display was realized with a high pixel yield. The thin film red LED AM micro-display delivers a luminance of 2.35 x 10(4) cd/m(2) at full-load conditions and can render images with 4-bit grayscale. This work not only provides a manufacturing-friendly approach for monolithic thin film red LED micro-displays, but also brings the possibility of hybrid integration with blue/green LEDs to achieve full-color LED micro-displays.