Photoreflectance and Raman Study of Surface Electric States on AlGaAs/GaAs Heterostructures

Figure 9

Raman scattering of M1, M4, and M5 heterostructures capped with a 25 nm GaAs layer and passivated with 0, 1, and 2 Si-ML, respectively. A 532 nm laser was used as excitation source.