Dresden 2009 – wissenschaftliches Programm
HL 22.6: Vortrag
Dienstag, 24. März 2009, 16:15–16:30, BEY 118
GaInN quantum wells with high indium concentrations on polar and nonpolar surfaces — •Holger Jönen1, Torsten Langer1, Daniel Dräger1, Lars Hoffmann1, Heiko Bremers1, Uwe Rossow1, Sebastian Metzner2, Frank Bertram2, Jürgen Christen2, and Andreas Hangleiter1 — 1Institut für Angewandte Physik, TU Braunschweig — 2Institut für Experimentelle Physik, Otto-von-Guericke-Universität Magdeburg
The strong decrease of the internal quantum efficiency (IQE) of GaN based light emitters towards the green spectral region is a well known problem. Beside a degrading material quality the stronger piezoelectric field with increasing indium content reduces the quantum efficiency. A promising way to solve this problem is to grow on non-polar surfaces such as the (1100) of the wurtzite crystal structure. In this case there is no field in growth direction and therefore devices might be more efficient. However, growth conditions may significantly differ from those on conventional c-plane surfaces. In this contribution we discuss the indium incorporation in c-plane and m-plane GaInN quantum wells.
Our samples were grown by low pressure MOVPE and characterized by SEM, XRD, CL and PL measurements. The In content of GaInN layers increases with decreasing growth temperature and seems to be comparable for both surfaces under same growth conditions. However, for high In concentrations above 30% possible relaxation and a degradation of the quantum wells during high temperature growth steps become critical issues.