Real-time investigation of In segregation by RHEED measurements during MBE growth of InGaAs on GaAs[001]

Since its discovery, surface segregation in III/V semiconductor alloys has been the subject of numerous studies, in particular in InGaAs/GaAs quantum wells because of their importance to the optoelectronics and microwave industries. Therefore, new experimental data and techniques about this subject are welcome in order to identify the physical mechanisms responsible for the effect. In the present work, we propose a simple but efficient way to determine, in situ and in real time, the surface segregation of indium (In) atoms during the growth of InGaAs layers on GaAs[001] substrates. Our method, that is based on the interpretation of the intensity decay of the reflection high-energy electron diffraction (RHEED) oscillations, differs from the other few RHEED studies by the fact that those only provide qualitative results or are restricted to a specific material or growth technique.