Research on Performance of Red Vertical AlGaInP/GaAs Light-Emitting Diodes Influenced by Current Crowding

The authors show that the performance of red vertical AlGaInP/GaAs light-emitting diodes is compromised by the current crowding (CC) effect in the moderate-current (space charge region dominates in the device performance) and high-current (series resistance dominates in the equivalent circuit of a device) domains. Depending on the contact pattern, a remarkable part of the performance degradation comes as a result of the electrical power lost on the series resistance (~17%). CC affects the ideality factor and causes the current spreading length to decrease from 425 at low currents to 75 at a current of 250 mA.