Planar regions of GaAs (001) prepared by Ga droplet motion

Surface Electron Microscopy of Ga Droplet Dynamics on GaAs (001)

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 ...

Formation of Spatially Addressed Ga(As)Sb Quantum Rings on GaAs(001) Substrates by Droplet Epitaxy

In this work we report on the ability to form low density Ga(As)Sb quantum ring-shaped nanostructures (Q-rings) on GaAs(001) substrates by the droplet epitaxy technique. The Q-rings are formed by crystallization of Ga droplets under antimony flux. After being capped by a GaAs layer, these nanostructures show surface mounding features that are correlated with the buried nanostructures, as demons...

Fundamental role of arsenic flux in nanohole formation by Ga droplet etching on GaAs(001)

Nanoholes with a depth in the range of tens of nanometers can be formed on GaAs(001) surfaces at a temperature of 500°C by local etching after Ga droplet formation. In this work, we demonstrate that the local etching or nanodrilling process starts when the Ga droplets are exposed to arsenic. The essential role of arsenic in nanohole formation is demonstrated sequentially, from the initial Ga dr...

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...

Elemental diffusion during the droplet epitaxy growth of In(Ga)As/GaAs(001) quantum dots by metal-organic chemical vapor deposition