Junction temperature rise due to self-heating effects in GaInN blue light-emitting diodes

Originating from a non-radiative recombination in the active region of a light-emitting diode (LED), the self-heating effect was investigated under continuous wave (cw) operation with a GaInN blue LED. Current-voltage (I-V) characteristics under pulse operation that lacked self-heating were measured and compared with the corresponding I-V measurement under the cw operation. Accordingly, a comparison of the measured I-V curves enabled estimation of the junction temperature of the LED during the cw operation. The junction temperature of the device increased as high as 323 K at an input current of 480 mA. The operating current showed a weaker temperature dependence in accordance with the bias increase, which is explained by the expansion of the Shockley diode equation.