A High-Resolution Transmission Electron Microscopy Study of MBE Grown $GaAs/Al_{0.3}Ga_{0.7}A_{s}$ Layers

MBE로 성장시킨 $GaAs/Al_{0.3}Ga_{0.7}A_{s}$층의 고분해능 투과전자현미경에 의한 연구

A cross-sectional transmission electorn microscopy study of the MBE grown GaAs/Al0.3 Ga0.7As layers was carried out at high-resolution so that the atomic arrangement of the well, barrier and the interface could be understood on an atomic level. Results show that the images reveal directly the atomic structure of the GaAs, Al0.3Ga0.3 Ga0.7 As interface is sharply defined but is not smooth on the atomic scale. The roughness arises from the presence of hills with heights of several{002} GaAs interplanar spacings. The atomic arrangement at the interface is almost completely coherent without any structural disorder. Alloy clustering at the interface was not observed.