Abstract
Deep-level defects formed in InGaN:Mg have been investigated by photoluminescence (PL) spectroscopy. Undoped In0.07Ga 0.93N exhibits strong bandedge emission at 3.05 eV. Upon Mg doping the bandedge emission quenches and a 2.45 eV green band with a full-width at half-maximum of 800 meV dominates the room temperature PL spectrum. This band is attributed to donor-acceptor pair (DAP) recombination involving Mg acceptors and nitrogen vacancy donors. A decrease in the DAP emission bandwidth and an S-shaped emission shift with increasing temperature were observed and attributed to compositional fluctuations. In order to decrease the fluctuations, InGaN:Mg epilayers with a GaN capping layer were annealed at high temperature. As a result of the fluctuation reduction a fine structure related to phonon replicas was resolved. The measured phonon energy and the Huang-Rhys factor were 105meV and 6.3, respectively, indicating strong electron-phonon coupling is responsible for the large width of the green band.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 470-474 |
| Number of pages | 5 |
| Journal | Physica B: Condensed Matter |
| Volume | 340-342 |
| DOIs | |
| State | Published - Dec 31 2003 |
| Event | Proceedings of the 22nd International Conference on Defects in (ICDS-22) - Aarhus, Denmark Duration: Jul 28 2003 → Aug 1 2003 |
Keywords
- InGaN
- Photoluminescence
- Self-compensation
- Wide-gap semiconductors
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering