Low Temperature Electroluminescence of Green and Deep Green GaInN/GaN Light Emitting Diodes
Abstract
Electroluminescence of GaInN/GaN multiple-quantum-well (QW) light-emitting diodes emitting in the green spectral region is analyzed at variable low temperature. Spectra are dominated by QW emission at RT throughout 7.7 K. Below 150 K, donor-acceptor pair recombination appears that must be assigned to residual impurities in either the barriers or the p-layers. The current-voltage behavior reveals shunt paths that carry up to several mA at low bias voltages. Below 20 K those paths are frozen out, but the device still emits predominantly from the QW. The peak energy exhibits a blue shift from RT to 158 K followed by a red shift from 158 K to 7.7 K. The deeper binding energy at low temperatures can hardly be affect by the injection current indicating that saturation of low-density states cannot be responsible for the transition between red and blue shifts.
- Publication:
-
Advanced Semiconductor Devices
- Pub Date:
- June 2007
- DOI:
- 10.1142/9789812770332_0005
- Bibcode:
- 2007asd..conf...25L
- Keywords:
-
- GaInN LED;
- external quantum efficiency;
- quantum confined Stark effect