Surface Electron Microscopy of Ga Droplet Dynamics on GaAs (001)
نویسنده
چکیده
We describe the design and application of a surface electron microscope which has been constructed to study the in situ growth dynamics occurring on III-V semiconductor surfaces during molecular beam epitaxy. Mirror electron microscopy and photo-emission electron microscopy (PEEM) are used to ellucidate the physics of Langmuir (free) evaporation of GaAs. Of particular interest is the formation and motion of Ga droplets across the surface. We also describe the surface electron microscopy technique known as Lloyd’s Mirror PEEM which has been developed to image surface topography in real-time. This is applied to determine Ga droplet contact angles during evaporation and the extension to synchrotron based Lloyd’s Mirror x-ray PEEM (XPEEM) is considered.
منابع مشابه
Ga droplet surface dynamics during Langmuir evaporation of GaAs
We describe the design and application of a low-energy electron microscope (LEEM) dedicated to the study of III–V materials. Recent studies of Langmuir (free) evaporation of GaAs(001) have been reviewed. Running Ga droplets are observed, and the motion is predicted and shown to slow and stop near a characteristic temperature. Striking bursts of Bdaughter[ droplet nucleation accompany the coales...
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