Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
Thin Films | Monday Sessions |
Session TF-MoM |
Session: | Nanostructured Surfaces and Thin Films: Synthesis and Characterization I |
Presenter: | Esteban Cruz-Hernandez, CIACYT, Universidad Autonoma de San Luis Potosi, Mexico |
Correspondent: | Click to Email |
Energetically unstable crystalline surfaces, among their uses, can be templates for the self-assembling of semiconductor structures at the nanometric level. Highly uniform structures such as quantum wires can now be fabricated from the self-assembly of nanometric facet arrays produced by using high-index substrates and epitaxial techniques such as Molecular Beam Epitaxy (MBE) [1]. However, the self-assembling of more complex nanostructures such as Y-junctions (produced by the union of two semiconductor nanowires) is a more complex problem. In MBE the growth process is carried out under non-equilibrium conditions, then the nonlinear evolution processes (such as step-bunching, meandering instabilities, and coarsening) that produce a very rich variety of surface morphologies have to be understood to precisely control the self-assembly of such complex nanostructures.
The control on the assembly of semiconductor Y-junctions could have great potential in technological applications (for example, in nanoelectronics as quantum logic gates) and one-dimensional physics exploration. Until very recently, related works on nanometric Y-junctions have been based on carbon nanotubes and graphene [2, 3], but not with semiconductor crystalline materials. In this contribution we report on the high-order and two-dimensional mechanisms in the MBE growth of GaAs on high-index GaAs substrates, which allow the formation of a regular alternating pattern of bifurcated nanowires [4] with suitable dimensions to form a Y-junction electron gas device.
[1] E. Cruz-Hernandez, S. Shimomura, and V. H. Mendez-Garcia, Appl. Phys. Lett. 101, 073112 (2012).
[2] Zhen Yao, Henk W. Ch. Postma, Leon Balents, and Cees Dekker, Nature 402, 273 (1999).
[3] A. Jacobsen, I. Shorubalko, L. Maag, U. Sennhauser, and K. Ensslin, Appl. Phys. Lett. 97, 032110 (2010)
[4] R. Mendez-Camacho, M. Lopez-Lopez, V. H. Mendez-Garcia, D. Valdez-Perez, E. Ortega, A. Benitez, A. Ponced and E. Cruz-Hernandez, RSC Adv. 7, 17813 (2017).