Simulation based experimental study of the temperature and power density distribution in a high-power LED

Temperature variations strongly influence the performance of light-emitting diodes (LEDs). The electrical properties of the LED, the power and the quality of the emitted light, and their long-term stability depend on the operating temperatures. The required electrode structures of LEDs lead to an inhomogeneous current distribution, heat generation, and light emission, which additionally exhibits a time-dependence. A high-power LED chip is studied on a microscopic scale by electro-thermal 2D-simulations, and by thermography. Temperature variations in the active LED region caused by the electrode structure are shown, and their steady-state and transient consequences are discussed.