Improvement of hetero-interface abruptness in MOVPE growth of InGaAs/InP quantum wells by in-situ kinetic ellipsometry

摘要

Interdiffusion of arsenic and phosphorus at InGaAs/InP interfaces causes degradation of hetero-interface abruptness. This problem limits the use of thin quantum wells (QWs) in this material system. Previously, we studied the As-P exchange process at the interface between InGaAs and InP in metal-organic vapor phase epitaxy (MOVPE) by using in-situ kinetic ellipsometry. We have studied here how the information from the in-situ kinetic ellipsometry could be utilized to optimize the growth condition and to secure the hetero-interface abruptness in InGaAs/InP QWs. As a results, we could improve hetero-interface abruptness by two different ways that the in-situ kinetic ellipsometry results suggested.