In situ growth rate measurements by normal-incidence reflectance during MOVPE growth

摘要

We present an in situ technique for monitoring metal-organic vapor phase epitaxy growth by normal-incidence reflectance. This technique is used to calibrate the growth rate periodically and to monitor the growth process routinely. It is not only a precise tool to measure the growth rate, but also very useful in identifying unusal problems during a growth run, such as depletion of source material, deterioration of surface morphology, and problems associated with an improper growht procedure. We will also present an excellent reproducibility ((+-)0.3% over a course of more than 100 runs) of the cavity wavelength of vertical-cavity surface emitting laser structures with periodic calibration by this in situ technique.