Influence of p-electrode on the characteristics of resonant-cavity light-emitting diodes

The performance and characteristics of resonant-cavity light-emitting diodes (RCLEDs) are obviously affected by p-electrode shape, since the RCLEDs are lack of the current spreading layer. The oxide-confined RCLEDs with two types of p-electrode have been fabricated. By comparing characteristics of the two types of RCLEDs, the voltage at 20mA of the RCLED with single ring electrode is 0.5V greater than that with double rings. At 20mA, the light output power of the RCLEDs with the single ring electrode and the double ring electrode is respectively 1.228mW and 1.094mW. Light output power saturation rate of RCLED with the single ring is faster than that with the double rings. At low current, since the influence of heat effect on the device performance is not obvious and the single ring electrode has better light extraction for larger emitting area, the light output power of RCLED with the single ring is higher than that with the double rings. At high current, as the influence of heat effect is dominant as compared with light extraction and the single ring electrode has greater heat effect for smaller ohmic contact area, the light output power of RCLED with the single is lower than that with the double rings. The great heat generated affects the device reliability. In conclusion, RCLEDs with the single ring electrode has greater light output power at lowF injected current but worse device reliability for great heat effect.