Carrier profile for In(0.35)Ga(0.65)As/GaAs multiquantum well lasers from capacitance-voltage measurements

The carrier profile for MBE grown ln(ind 0,35)Ga(ind 0.65)As/GaAs multiquantum well laser structures with nominally undoped and beryllium-doped active regions was determined by using the capacitance- voltage (C-V) technique at room temperature. A simple theoretical model was used to extract the impurity concentration and the quantum-well carrier density from the experimental profiles. We obtained a high carrier concentration in nominally undoped devices caused by a strong growth temperature dependent Be diffusion from the p-cladding layer, and no difference between doped samples with different nominal dopant location.