IN-SITU Monitoring Of OMVPE Of GaAs And Ga1-xAlxAs (x = 0.17) By Contactless Photoreflectance

We have successfully applied the contactless, non-invasive electromodulation method of photoreflectance as an in-situ sensor of the OMVPE process. The direct gaps of GaAs and Ga1-xAlxAs(x = 0.17) have been measured as a function of temperature up to 690°C, in-situ, under actual OMVPE growth conditions, including a rotating substrate holder (~ 500 rev/min) and flowing gases.