Structural Evolution During Formation and Filling of Self-patterned Nanoholes on GaAs (100) Surfaces
1 Institute of Nanoscale Science and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA
2 Department of Physics, Arizona State University, Tempe, AZ, 85287, USA
Nanoscale Research Letters 2008, 3:530-533 doi:10.1007/s11671-008-9194-5Published: 4 November 2008
Nanohole formation on an AlAs/GaAs superlattice gives insight to both the “drilling” effect of Ga droplets on AlAs as compared to GaAs and the hole-filling process. The shape and depth of the nanoholes formed on GaAs (100) substrates has been studied by the cross-section transmission electron microscopy. The Ga droplets “drill” through the AlAs layer at a much slower rate than through GaAs due to differences in activation energy. Refill of the nanohole results in elongated GaAs mounds along the [01−1] direction. As a result of capillarity-induced diffusion, GaAs favors growth inside the nanoholes, which provides the possibility to fabricate GaAs and AlAs nanostructures.