Luminescence of an InGaN/GaN multiple quantum well light-emitting diode

In GaN/GaN multiple quantum wells (MQW) and blue MQW light-emitting diodes (LEDs) were grown by metalorganic vapor phase epitaxy (MOVPE). Band-gap nar rowing of the PL spectra for the InGaN/GaN MQW LEDs can be observed at room temperature. In addition, the emission wavelength of EL and PL spectra for the MQW blue LEDs exhibit a blue-shift phenomenon while increasing the inj ection current and laser power, respectively. This luminescence behavior ca n tentatively be understood as a competition between a spectral red-shift m echanism of piezoelectricity-induced quantum-confined Stark effect (PQCSE) and a blue-shift mechanism of band-filling and charge screening effects. (C ) 2000 Elsevier Science Ltd. All rights reserved.