Laser Lift-Off Process of GaN-Based Micro LED Chip with High Yield and Flatness

Abstract

Abstract: In this study, a large area laser lift-off (LLO) of GaN-based micro light-emitting diodes (Micro LED) was achieved using an excimer laser at 248 nm. The critical laser energy density required for separation of devices is 800~835 mJ·cm^-2. The separated device is intact with a residual stress of 0.071 4 GPa and a mean square roughness of 0.597 nm, which is much lower than that of the LLO method reported so far. This study provides a promising idea for the fabrication of GaN-based Micro LED chips with high quality and high efficiency, which is of great significance for the fabrication of flexible GaN-based devices.

Key words: gallium nitride, micro light-emitting diode, laser lift-off, excimer laser, production yield, flatness

CLC Number:

TN364

YUE Long, XU Yu, WANG Jianfeng, XU Ke. Laser Lift-Off Process of GaN-Based Micro LED Chip with High Yield and Flatness[J]. Journal of Synthetic Crystals, 2023, 52(5): 805-811.

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