▎ 摘　　要

One of the bottlenecks in the implementation of graphene as a transparent electrode in modern opto-electronic devices is the need for complicated and damaging transfer processes of high-quality graphene sheets onto the desired target substrates. Here, we study the direct, plasma-enhanced chemical vapor deposition (PECVD) growth of graphene on GaN-based light-emitting diodes (LEDs). By replacing the commonly used hydrogen (H-2) process gas with nitrogen (N-2), we were able to suppress GaN surface decomposition while simultaneously enabling graphene deposition at <800 degrees C in a single-step growth process. Optimizing the methane (CH4) flow and varying the growth time between 0.5 h and 8 h, the electro-optical properties of the graphene layers could be tuned to sheet resistances as low as similar to 1 k omega/ with a maximum transparency loss of similar to 12%. The resulting high-quality graphene electrodes show an enhanced current spreading effect and an increase of the emission area by a factor of similar to 8 in operating LEDs.