Optical properties of InGaN/GaN multi-quantum wells with Si doped barriers are studied using cw and time resolved photoluminescence (TRPL) and photoluminescence excitation (PLE) spectroscopy. The room temperature carrier lifetime depends strongly on the Si doping level in the quantum well barriers, decreasing from 10ns to 1 ns as the doping level is increased from unintentionally doped to 5 × 1018 cm-3 (Si:GaN). The shift between the absorption edge and emission peak decreases from 220 meV to 110meV as the doping is increased. Temperature dependent photoluminescence measurements indicate a higher density of non-radiative centers in the undoped structures.
- Multi-quantum wells