Control of Impurities in the Epitaxial Growth of High Quality GaAs.

摘要

A research program is described on the topic of impurity incorporation during the growth of GaAs epitaxial layers. The major portion of the research was the design, construction, and characterization of a molecular beam mass spectrometry (MBMS) system and its use as a diagnostic analytical tool to evaluate typical gaseous environments used in the growth of III-V single crystal layers. The fundamental gas dynamics of the MBMS sampling process were studied as well as the limitations and correction factors for this technique. Two crystal growth environments were analyzed: a liquid phase epitaxial (LPE) GaAs growth system; and an organometallic vapor phase epitaxy (OMVPE) system. In the former system, it was shown that there are significant concentrations of O, C, Si gaseous species in the gas ambient which appear to be the major potential impurities. For OMVPE, two topics were emphasized: the side reactions of the organometallic (OM) reactants, particularly those involving oxygen containing species; and the graphite-OM interaction.