Damage‐Free Organic Passivation Layer for Improved Optical and Electrical Performance of InGaN/GaN Blue Micro‐LEDs

Abstract Micro light‐emitting diodes (μ‐LEDs) are widely adopted in high‐performance display applications due to their exceptional efficiency, brightness, and stability. However, as the chip size decreases, the external quantum efficiency (EQE) of μ‐LEDs significantly declines due to sidewall defects primarily caused by plasma reactive ion etching. In this study, a novel passivation strategy is proposed for μ‐LEDs using an organic passivation layer, poly(1,3,5‐trimethyl‐1,3,5‐trivinyl‐cyclotrisiloxane) (pV3D3). The passivation layer is conformally deposited using initiated chemical vapor deposition (iCVD) under plasma‐free and solvent‐free environment at near‐room temperature (40 °C). The impact of pV3D3 passivation on the optical and electrical performance of μ‐LEDs is thoroughly investigated and compared with that of a conventional Al 2 O 3 passivation layer deposited via thermal atomic layer deposition. The μ‐LEDs (20 × 20 µm 2 ) with pV3D3 passivation achieved a 235% higher photoluminescence intensity, 177% higher electroluminescence intensity at 0.1 A cm −2 , and 61% higher peak EQE compared with the Al 2 O 3 passivation layer. Thus, the plasma‐free, solvent‐free, and low‐temperature iCVD process improves the performance of μ‐LEDs.