Simulated and experimental analyses of the thermal dissipation of organic light-emitting diodes

Thermal management is important for organic light-emitting diodes (OLED). Thermal dissipation will significantly affect the electroluminescence and lifetime of OLEDs. In this work, we established a simple thermal resistance model to calculate the thermal distribution of OLEDs and theoretically simulated the results through COMSOL finite element simulation. We find that the maximum temperature for the circular OLED with a diameter of 400 µm is more than 20 ℃ higher than that of the OLED with a smaller diameter of 200 µm. Moreover, the maximum temperature of the rectangular device is 8 ℃ lower than that of the square device with the same active area. Most interestingly, the temperature at the center of the luminescence is about 12 ℃ higher than that of the edge under the same conditions. The simulation well matches the experiment without requiring the use of fitting parameters. The results represented an important advance in the thermal distribution of OLEDs and the potential design of alternative substrates for thermal management applications.