Theory and experiment of step bunching on misoriented GaAs(001) during metalorganic vapor-phase epitaxy

Abstract

Articles you may be interested inElemental diffusion during the droplet epitaxy growth of In(Ga)As/GaAs(001) quantum dots by metal-organic chemical vapor deposition Appl. Phys. Lett. 104, 022108 (2014); 10.1063/1.4859915Three-step growth of metamorphic GaAs on Si(001) by low-pressure metal organic chemical vapor deposition Mask pattern interference in AlGaInAs selective area metal-organic vapor-phase epitaxy: Experimental and modeling analysisWe present experiments and an accompanying theory for the growth modes during metalorganic vapor-phase epitaxy on vicinal GaAs͑001͒. Our theory is based on a model that takes account of deposition, diffusion, and dissociation of molecular precursors, and the diffusion and step incorporation of atoms released by the precursors. The experimental conditions for island nucleation and growth, step flow, and step bunching are reproduced by this model, with the step bunching instability caused by the difference in molecular dissociation from above and below step edges.

Low-angle misorientation dependence of the optical properties of InGaAs/InAlAs quantum wells

“…Recent metalorganic vapor phase epitaxy (MOVPE) growth studies of (Al)GaAs on GaAs have shown that small misorientations in the range 0-0.61 on the GaAs substrate can have a dramatic impact in the optical and transport properties of the grown layers, allowing record material properties to be achieved for MOVPE, with results comparable with those obtainable by the best MBE systems [5,6]. These improvements have been shown to correlate with the substrate surface ordering, where the best optical properties were obtained from growth on substrates intentionally miscut at 0.21 off (1 0 0), which corresponds to the onset of the appearance of step bunching on the GaAs surface [5,7,8]. A similar study for the growth of InGaAs on low-angle misorientated InP substrates has not been reported, and is the subject of this paper.…”

Self-Limiting Evolution of Seeded Quantum Wires and Dots on Patterned Substrates

“…The systematic characterization of the self-limiting profile as a function of the growth conditions and composition, a key ingredient in model development, has not been readily available because of the painstaking procedures needed to acquire these data. On the other hand, previous work [18] has indicated that a reaction-diffusion model based on the surface diffusion and decomposition at step edges of the group-III precursor explains the morphology of misoriented GaAs(001) surfaces during MOVPE. In fact, the large length scales of typical etched patterns effectively preempt kinetic Monte Carlo simulations except for qualitative studies [19], leaving a continuum description as the only viable alternative for a quantitative theory.…”

Effect of carrier gas and substrate misorientation on the structural and optical properties of m-plane InGaN/GaN light-emitting diodes

“…3). Finally, for misorientation angles greater than 1.51, progressively larger lateral surface undulations parallel to the [1 1 2 0] a direction were observed, which we attribute to step bunching at large misorientation angles [16]. With an increase in misorientation angle the intensity of the higher order superlattice (SL) peaks decreased, most likely due to increased interface roughness (Figs.…”

“…Previous work on the MOCVD growth of III-arsenide-and III-phosphide-based materials established that substrate misorientation can have significant effects on surface morphology [16], impurity incorporation [17], alloy composition [18], and photoluminescence (PL) spectra [18,19]. Initial studies on InGaN/GaN LEDs grown on free-standing m-plane substrates used nominally on-axis substrates [20].…”