Optical in situ calibration of Sb for growing disordered GaInP by MOVPE

• RAS has been used as a calibration tool of surfactants (Sb) for GaInP growth in MOVPE.
• RAS signal at 3.02 eV is sensitive to the amount of Sb on the surface.
• Surfactant effect of Sb on GaInP can be in situ monitored.

Reflectance Anisotropy Spectroscopy (RAS) was employed to determine the optimal specific molar flow of Sb needed to grow GaInP with a given order parameter by MOVPE. The RAS signature of GaInP surfaces exposed to different Sb/P molar flow ratios were recorded, and the RAS peak at 3.02 eV provided a feature that was sensitive to the amount of Sb on the surface. The range of Sb/P ratios over which Sb acts as a surfactant was determined using the RA intensity of this peak, and different GaInP layers were grown using different Sb/P ratios. The order parameter of the resulting layers was measured by PL at 20 K. This procedure may be extensible to the calibration of surfactant-mediated growth of other materials exhibiting characteristic RAS signatures.