Application of reflectance anisotropy spectroscopy to laser diode growth in MOVPE

The growth of layer structures for visible and near-infrared laser diodes is investigated in metal-organic vapour phase epitaxy (MOVPE) under production-like conditions using reflectance anisotropy spectroscopy (RAS). For this purpose the dependence of the reflectance anisotropy (RA) signal on doping type and level is studied for AlGaAs and AlGaInP. The growth of complete layer structures can then be fingerprinted by the significant features of the RA spectra. The reproducibility of the growth process is controlled using the RA transients taken with a high time resolution at a fixed photon energy. Additionally, the emission wavelength of a GaAsP quantum well (QW) can be correlated to the RA level during QW growth. Information about buried interfaces can also be gained from the RA transients as demonstrated for AlGaInP laser structures.