IDENTIFICATION OF ORDERED AND DISORDERED GA0.51IN0.49P DOMAINS BY SPATIALLY-RESOLVED LUMINESCENCE AND RAMAN-SPECTROSCOPY

Ga0.51In0.49P layers were grown by organometallic vapor phase epitaxy on grooved GaAs(001) substrates misoriented by 9-degrees. The formatio n of adjacent ordered and disordered domains has been observed on such substrates. The combination of both Raman and cathodoluminescence mea surements allows for an independent determination of composition by an alyzing the frequency positions of the optical phonon modes (with an a ccuracy of 1%) and of the band gap from the luminescence at the same p osition on the sample. Furthermore, ordered and disordered domains can be clearly identified from their different polarization selection rul es observed in the Raman spectra. The cathodoluminescence spectra show shifts of the luminescence maxima of up to 100 meV for ordered and di sordered domains of the same composition.