Density limits of high temperature and multiple local droplet etching on AlAs
Abstract
The density of nanoholes created by self-assembled Al droplet etching of AlAs surfaces during molecular beam epitaxy is studied. We find a clear decrease of the hole density with increasing etching temperature T up to a threshold temperature T = 620 ° C. At T > 620 ° C, the hole density saturates at a minimum of 2 ×108cm-2. We attribute this saturation to a change of the AlAs surface reconstruction. On the other hand, at reduced T, hole densities up to 2 ×109cm-2 have been achieved. However, this hole density increase is accompanied by a reduction of the hole depth. To generate high density holes with larger depth suited for quantum dot fabrication, we have studied the effect of repeated etching steps.
- Publication:
-
Journal of Crystal Growth
- Pub Date:
- March 2014
- DOI:
- 10.1016/j.jcrysgro.2013.11.044
- Bibcode:
- 2014JCrGr.389...18K
- Keywords:
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- A1. Atomic force microscopy;
- A1. Etching;
- A1. Surface structure;
- A1. Nanostructure;
- A3. Molecular beam epitaxy;
- B2. Semiconducting III-V materials