I n s i t u growth rate measurements during molecular beam epitaxy using an optical pyrometer

Abstract
An optical pyrometer has been used to measure apparent temperature oscillations during the growth of GaAs/GaAlAs heterostructures by molecular beam epitaxy. The oscillations are due to an optical interference effect in the epitaxial layers and the period can be related to both growth rate and alloy composition. Measurements can be carried out on rotating substrates throughout the deposition cycle of complex device structures, and provide a convenient means of monitoring the uniformity of the deposition process.