Influence Of Nitrogen On Hole Effective Mass And Hole Mobility In P-Type Modulation Doped Gainnas/Gaas Quantum Well Structures

Nitrogen dependence of hole effective mass and hole mobility in p-type modulation doped Ga0.68In0.32NyAs1-y/GaAs quantum well structures with y = 0, 0.009, 0.012, 0.017 are investigated using magnetotransport and Hall effect measurements. Observed N-dependent reduction of the hole effective mass is explained by stronger confinement of holes. Hole effective mass is also found to have hole density dependence due to the strain-induced valance band non-parabolicity. A tendency to decrease in hole effective mass upon annealing can be attributed to the reduction of well width and/or decrease in hole density. A significant improvement in low temperature hole mobility is observed after annealing. (C) 2013 AIP Publishing LLC.