In‐situ STM Study of MBE Growth Process

High‐density arrays of quantum dots (QDs) can easily be grown by “self‐assembled” methods. However, the precise atomic‐level mechanism of “self‐assembly” is not understood, which hampers control over QD size, density, and distribution for particular applications. Therefore, an in‐situ evaluation technique for observing the growth process is necessary and indispensable. A scanning tunneling microscope (STM) is a good technique to observe the surface at atomic level, but it dislikes vibrations and material depositions. So, usually its observation is after transporting the sample from a molecular beam epitaxy (MBE) growth chamber to the STM through a gate valve, resulting in the temperature of the sample being returned to room temperature. Since the real in‐situ observation cannot be done with this ordinary method, we develop a “STMBE” system in which the STM is placed completely inside the MBE growth chamber, and with this system, the surface structure is analyzed centering on the in‐situ STM observation of the InAs QD self‐assembly process on GaAs(001).