MinJae Kim

All Publications

• Near-planar light outcoupling structures with finite lateral dimensions for ultra-efficient and optical crosstalk-free OLED displays NATURE COMMUNICATIONS Kim, M., Kim, J., Yoo, S. 2025; 16 (1): 11606

  Abstract

  The stratified structure of organic light-emitting diodes (OLEDs) confines much of the generated light within substrates or organic layers, limiting outcoupling to air. Macroscale half-ball lenses extract most substrate-trapped light but compromise the inherent planarity of OLEDs, while microlens arrays (MLAs), only tens of micrometres tall, preserve planarity yet provide only modest enhancements, particularly with limited lateral dimensions. Here, we introduce a systematic strategy to enhance outcoupling while maintaining near-planarity. By jointly tailoring the OLED device stack and the topography of near-planar outcoupling structures, we overcome the limited prompt extraction responsible for the modest performance of conventional MLAs. Our optimized devices reach an external quantum efficiency of 48.0% and a current efficiency of 192 cd A⁻¹, surpassing bare OLEDs (35.6%, 102 cd A⁻¹) and MLA-attached OLEDs (35.4%, 150 cd A⁻¹). This approach addresses trade-offs among intrusiveness, aperture ratio, and performance, providing a promising route to ultra-efficient, optical-crosstalk-free OLED displays.

  View details for DOI 10.1038/s41467-025-66538-6

  View details for Web of Science ID 001651009000004

  View details for PubMedID 41285816

  View details for PubMedCentralID PMC12749176

• Ultralow-power carbon dioxide sensor for real-time breath monitoring DEVICE Kim, M., Choi, D., Kang, C., Yoo, S. 2025; 3 (5)

  View details for DOI 10.1016/j.device.2024.100681

  View details for Web of Science ID 001502065700004