Dislocation movement in GaN films
Moram, M A and Sadler, T C and Haeberlen, M and Kappers, M J and Humphreys, C J
We demonstrate that significant dislocation movement occurs below the surface of heteroepitaxial c-plane GaNfilms during their growth by metalorganic vapor phase epitaxy.Dislocations move primarily by vacancy-assisted climb, which appears to be driven by the high in-plane biaxial stresses present during growth.Annealing low dislocation density (4.3×10\^8 cm−2)GaNfilms promotes dislocation climb and thus reduces both dislocation densities and in-plane stresses (at high temperatures), independent of epilayer growth conditions.
Department of Materials
Imperial College London
Royal School of Mines
London, SW7 2AZ - UK