Atomic scale saw by dislocation slipping: A new method to generate one-dimensional structure

Abstract

A new method to generate one-dimensional (1D) semiconductor structures or controllable steps on a surface is proposed. This method, which is not material specific, is based on intrinsic dislocation slip properties and heterogeneity of straining. Dislocations can be used as an atomic scale saw to cut two-dimensional structures (2D) in order to obtain 1D wires. Atomic force microscope observations of GaAs surfaces and transmission electronic microscopy cross sections of GaAs/GaAlAs single quantum wells are presented to demonstrate the feasibility of the method. Although being based on dislocation slipping this method is shown to preserve the optical and crystalline properties of the starting 2D structure as confirmed by photoluminescence spectra.

Effect of coherency strain on the deformation of InxGa1−xAs superlattices under nanoindentation and bending

“…These steps are formed from localised deformation along shear bands such as those evident in the bright field image of superlattice P ( figure 11). The passage of dislocations effectively 'cuts' the superlattice in a process that has previously been described as 'quantum well sawing' [18]. In contrast to the nanoindentation deformation this shearing of the superlattice creates no rotation of the lattice as is clear from the diffraction patterns which lack any asterism.…”

Correlation between magnetism and structural relaxation in thin Fe(001) films patterned by the atomic saw method

“…23,24 The so-called atomic saw ͑AS͒ method was developed by Peyrade and co-workers. 18,19 It consists of applying a uniaxial compressive stress on a sample in order to favor the plastic deformation, i.e., the dislocation slipping through the whole system ''substrate and epitaxial film.'' When a dislocation ͑respectively, n dislocations͒ crosses the substrate-film interface, it creates a lattice shift equal to one Burger vector b ͑respectively, n•b͒.…”

“…In theory, if n•b is greater than the film thickness, this layer is patterned into separated stripes. First applied to III-V semiconducting structures, 18 this method has been successfully used to cut Fe thin films epitaxially grown on MgO͑001͒ into iron ribbons and dots. 20,25 The plastic deformation of the whole sample induces dislocation slip throughout the MgO substrate and the thin films along the activated slip systems of the MgO substrate.…”

“…18,19 We have shown that the uniaxial compression of these systems along the ͓100͔MgO direction could lead to the structuration of the Fe film into submicronic width Fe ribbons characterized by a magnetic easy axis perpendicular to the steps. 20 Magnetoelastic phenomenon was proposed to be at the source of the induced anisotropy without real experimental proofs.…”

Controlled dislocation slipping: an original method to create multiple quantum wire structures

“…[7] called the 'atomic saw' method, based on single crystal plasticity properties. This method consists in deforming a sample containing a 2D-structure in order to induce dislocation slipping throughout its volume.…”