Morphological Instability inInAs/GaSbSuperlattices due to Interfacial Bonds

Abstract

Synchrotron x-ray diffraction is used to compare the misfit strain and composition in a self-organized nanowire array in an InAs/GaSb superlattice with InSb interfacial bonds to a planar InAs/GaSb superlattice with GaAs interfacial bonds. It is found that the morphological instability that occurs in the nanowire array results from the large misfit strain that the InSb interfacial bonds have in the nanowire array. Based on this result, we propose that tailoring the type of interfacial bonds during the epitaxial growth of III-V semiconductor films provides a novel approach for producing the technologically important morphological instability in anomalously thin layers.

Morphological instability of two stressed spherical shells

“…Recently, the study of the surface instability in biaxially stressed solids has demonstrated that a new diamond morphology is favored when the stress is tensile in one direction and compressive in the orthogonal one (Berger et al, 2003). The effect of morphological change in self-organized nanowire array in InAs/GaSb superlattices due to interfacial bonds has been also studied (Li et al, 2005) as well as the competition as a strain-relief mechanism between misfit dislocations and stress-induced instability of a growing film/vapor interface in the case of an epitaxially stressed thin film on a substrate (Haataja et al, 2002). It can be noticed that the effect of stress on the directional solidification of a planar solid in an external thermal gradient has been carried out and the non-linear evolution of the roughness has been characterized (Cantat et al, 1998).…”

Elastic strains at interfaces in InAs/AlSb multilayer structures for quantum cascade lasers

“…6,7 In the InAs/GaSb system, which presents a similar problematic, a tensile GaAslike interface has been very recently evidenced by transmission electron microscopy (TEM) 8 The role of In-Sb interfacial bonds in morphological instabilities was also shown by synchrotron X-Ray diffraction. 9 and cross-sectional scanning tunneling microscopy (XSTM). 10 Intermixing at InAs/GaSb interfaces was also studied using Z-contrast microscopy 11,12 and atomic probe tomography.…”

Effect of interfacial strain on the morphological instability of noncommon anion semiconductor epitaxial films

“…When InSb interfacial bonds were intentionally grown, the InAs layer becomes unstable in a few monolayer thickness, but when GaAs interfacial bonds were grown, the InAs layer remains stable at a much larger thickness. 5,6 In this letter, we attempt to explain the small transition thickness of the aforementioned noncommon anion III-V heterostructures using a simple thermodynamic model following the work of Sasaki et al 2 We show that a large interfacial strain in the noncommon anion systems due to cross bonding at the heterointerface can significantly reduce the transition thickness of a small-strained film, thus providing a possibility of growing self-assembled nanostructures in many semiconductor systems with small lattice mismatch.…”

“…The nominal "InAs" layers in the superlattice experienced a compressive strain of f = −0.3% due to unintentional incorporation of approximately 12% Sb caused by Sb contamination and/or segregation. 6,14 When the interfacial bonding is chosen to be InSb, it experiences a much larger compressive strain of i = −5.9%. Consequently, according to Eq.…”

“…͑3͒, the experimentally observed small transition thickness for the MBE-grown InAs/ GaSb ͑001͒ superlattices with InSb interfacial bonds can be qualitatively understood. 5,6 For this system, two types of interfacial bonds were intentionally chosen, either InSb or GaAs. In both cases, using high-resolution x-ray diffraction, 6 the strain states of the film and the interfaces were determined.…”