We report on the reduction of defect densities in non-polar a-plane GaN films over r-plane sapphire achieved by epitaxial laterally overgrowth (ELOG) approach. A mask pattern was used to produce ELOG GaN with wing region width of about 30μm. Based on transmission electron microscopy (TEM) results, the window regions have stacking faults density of ∼10 6cm -1 and threading dislocation density of ∼10 10cm -2. Both ELOG Ga-face and N-face wing regions have stacking fault density of ∼10 5 cm -1, and dislocation density less than 10 8 cm -2. Cathodoluminescence studies reveal the difference in defect densities between N-faced and Ga-faced wings. GaN-based UV light-emitting diode formed on Ga-faced wing shows stronger quantum well emission and weaker parasitic emission than that formed on N-faced wing.
|Original language||English (US)|
|Title of host publication||Physica Status Solidi C: Conferences|
|Number of pages||4|
|Publication status||Published - 2005|
ASJC Scopus subject areas
- Condensed Matter Physics