Growth mechanisms and modeling for metalorganic chemical vapor deposition selective-area epitaxy on InP substrates

Abstract

Articles you may be interested inGrowth kinetics and mass transport mechanisms of GaN columns by selective area metal organic vapor phase epitaxy Heteroepitaxy of InP on Si(001) by selective-area metal organic vapor-phase epitaxy in sub-50nm width trenches: The role of the nucleation layer and the recess engineering Selective area growth of InP on lithography-free, nanopatterned GaAs(001) by metalorganic chemical vapor deposition J. Vac. Sci. Technol. B 32, 011210 (2014); 10.1116/1.4855035 Mask pattern interference in AlGaInAs selective area metal-organic vapor-phase epitaxy: Experimental and modeling analysisSelective area epitaxy of InP on masked ͑100͒ InP substrates is studied. InP layers are deposited between pairs of SiO 2 stripes using low-pressure metalorganic chemical vapor deposition. Layer thickness is investigated by surface profiling and scanning electron microscopy. For growth between oxide stripes, the growth velocity is enhanced by lateral diffusion of growth species from the masked region to the exposed region. Two transport mechanisms are known to exist: vapor phase diffusion and surface migration. However, most existing quantitative models focus only on the former. A new computational model, based on the diffusion equation with time dependent boundary conditions, is presented which describes the growth enhancement component due to surface migration. The role played by surface migration is shown to depend on nominal film thickness. The model correctly predicts a super growth enhanced region adjacent to the oxide. Previous quantitative models have not successfully described this aspect of growth near the oxide film.

A model for isotropic crystal growth from vapor on a patterned substrate

“…We don't study surface diffusion along the vertical part of the step and assume that atoms diffused over the corner are incorporated in the growing crystal instantly. This approximation is good if the mask thickness is much less than the mask region width, that is if h m ≪ ℓ (in ELOG the ratio h m /ℓ is usually < 0.1 [3,5,7], [11]- [15], [17]. In SAG this ratio is so small that the mask can be considered to be of vanishing thickness).…”

“…Under these conditions, the dominant lateral mass transport mechanism from the mask regions, for distances greater than a few (say 10) microns, is usually attributed to vapor-phase diffusion [5,6,7], [9]- [11]. However, surface diffusion usually dominates [6,7,11,17,18] for the growth in narrow windows bounded by narrow mask regions (< 10 microns) and it is this case (ELOG) that we are interested in studying.…”

Motion of contact line of a crystal over the edge of solid mask in epitaxial lateral overgrowth

“…As the result of coarsening, the single elevated corner (bump) followed by the α = 45 • inclined facet are again formed. Thus this numerical experiment suggests that the strong interfacial energy anisotropy may be one of the possible causes for the "bumpy" crystal shapes routinely observed in ELO deposits [1,4]. Fig.…”

“…The micrometer-scale selective growth is well-achievable by chemical vapor deposition or liquid phase epitaxy [1]- [4]; the ELO and SAG can be used also to grow nanostructures by the molecular beam epitaxy [5]- [7].…”

Strain relaxation and surface migration effects in InGaAlAs and InGaAsP selective-area-grown ridge waveguides

“…7 The vertical and lateral vapor-phase diffusion processes ͑VVP and LVP, respectively͒ and the surface migration of the metallorganic precursors are the three main mechanisms with different characteristic lengths that result in the thickness enhancement and compositional changes in the SAG regime. [2][3][4] Previous microbeam HRXRD studies of SAG structures with different ridge widths and surrounding oxide masks [8][9][10][11] have provided significant contributions to the development of the gas-phase diffusion models for SAG processes and allowed accurate calculations of the VVP and LVP effects with characteristic diffusion lengths in the range of 25 to 200 m. [12][13][14] In contrast, extensive investigation of the surface migration of the reacting metallorganic species within a typical diffusion length of a few microns has been carried out so far with imaging techniques only 2,3,13,14 and limited information is available on the strain and composition variation caused by this effect. 15,16 The long-range diffusion processes alone cannot properly describe the specifics of the micron-wide ridge formation in the SAG regime.…”