Defect structure in III-V compound semiconductors: Generation and evolution of defect structures in InGaAs and InGaAsP epitaxial layer grown by hydride transport vapor-phase epitaxy

Abstract

Articles you may be interested inImplications of excess strain in As compound/P compound III-V multilayer superlattices grown by metalorganic vaporphase epitaxy

Misfit dislocation formation in lattice-mismatched III - V heterostructures grown by metal - organic vapour phase epitaxy

“…In the present paper the misfit dislocation formation in lattice-mismatched single heterostructures in the GaAs/In x Ga 1−x As system is studied. The mismatch in the layers investigated is very low (≤10 −3 ), compared to other studies on this subject, with typical mismatches of about 10 −2 [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. This low mismatch results in low misfit dislocation densities, depending on the thickness of the (partially) relaxed layers.…”

“…However, first the 60 • dislocations are considered, since these dislocations are able to release the misfit strain. Observations of misfit dislocations, nucleating at the surface and propagating towards the interface, using transmission electron microscopy (TEM) in the diamond cubic and in the zincblende structure with mismatches of about 10 −2 [3,8,[32][33][34] have shown that these dislocations are V-shaped. No evidence for semicircular dislocations as assumed in theory [2,4], has been found experimentally.…”

“…A typical defect in strained layer epitaxy is the misfit dislocation, which is formed when the thickness of the epitaxial layer exceeds a certain, strain-dependent, critical layer thickness [1]. Several theoretical models for the calculation of this thickness, whereby the transition takes place from pseudomorphic (misfit-dislocation-free) to incoherent growth, have been proposed in the literature [1][2][3][4][5][6][7][8][9]. In the thermodynamic model of Matthews and Blakeslee [1], known as the mechanical equilibrium model, the critical layer thickness is calculated by balancing the elastic strain energy with the energy of a square grid of misfit dislocations.…”

“…However, in semiconductor films the density of grown-in dislocations is not high enough to relieve the strain energy completely. Therefore it is assumed [2][3][4][5][6][7][8][9] that new dislocations have to nucleate at the surface and propagate as half-loop dislocations towards the interface. In order to choose from these models the most realistic one, it is necessary to have a good knowledge of the relaxation processes.…”

Degradation of III–V Opto‐Electronic Devices

“…The elimination of growth-induced defects is very important. Defects generated from the interface (28,(81)(82)(83)(84)(85) and dislocation loops caused by high doping (42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)57), especially, lead to a lot of rapid degradation. The generation of interfacial defects can be suppressed by proper chemical treatment of the substrate prior to the growth, and also by protecting the surface of the substrate with cover-substrates.…”