Spectral and thermal properties of red AlGaInP RCLEDs for polymer optical fibre applications
The performance of red AlGaInP-based resonant cavity light-emitting diodes is investigated. Using angular dependent photomodulated reflectance to determine the quantum-well (QW) energy, and standard reflectivity measurements performed directly on devices to find the cavity mode (CM), angular and spectral features of the RCLED emission may be identified. The relative prominence of these features changes with drive current, QW-CM offset and temperature. Over the temperature range 15 to 75°C, devices with a larger offset (CM of longer wavelength than QW) are less temperature sensitive, but the prevalence of electron leakage reduces the effectiveness of such optimisations in increasing the output power at elevated temperatures.