Determination of Surface Chemical Species in GaAs Atomic Layer Epitaxy by In Situ Gravimetric Monitoring

Abstract
Atomic layer epitaxy (ALE) using a GaCl source is investigated by a real-time in situ gravimetric monitoring method. An ALE system with an electrobalance is used as a monitoring system. The direct gravimetric information from the growing surface in the growth system of ALE is monitored during an ALE cycle. It is shown that the surface chemical species are one-monolayer Ga atoms during H2 purge after GaCl supply, and the in situ gravimetric method is a powerful tool for the investigation of the ALE growth mechanism.