2014 Fast ellipsometers have made feasible real-time assessment of heterostructure growth in a vapour phase ambient. A fast ellipsometer/MO-VPE experimental system is described and the possibilities of in situ ellipsometry are investigated in the case of GaAs-(Al, Ga)As structure growth : qualitative assessment in real-time and quantitative assessment (growth rate, composition determination and...

A computational model for semiconductor crystal growth on a partially masked substrate under simplified liquid phase electroepitaxy conditions is developed. The model assumes isothermal diffusional growth, which is enhanced by applied DC current through crystal-solution interface. A finite-difference, front-tracking method is used to numerically evolve the interface. Computed examples show stro...

A major challenge that arises when growing GaN substrates in a single run process is the remaining curvature of the freestanding material after the removal of the foreign substrate. For a long time the dislocation density gradient has been suspected to be the cause. However, by conducting etching experiments, we have found that this cannot be the only reason. We postulate that the initial strai...

( 100) GaAs substrates with an Ag film about 45 nm thick were first annealed at 550 “C for 30 min in an Ar-flowing furnace (preannealing) . A 1 lo-nm-thick GaAs layer was then deposited on top of the preannealed (GaAs)/Ag samples, followed by an amorphous Ta-Si-N film that was deposited over the GaAs layer to serve as a cap layer to minimize the loss of As during the following annealing process...

The growth of epitaxial Si nanowires by a metal-catalyst-free process has been investigated as an alternative to the more common metal-catalyzed vapor-liquid-solid process. The well-aligned Si nanowires are successfully grown on a (111)-oriented Si substrate without any metal catalysts by a thermal treatment using silicon sulfide as a Si source at approximately 1200 °C. The needle-shaped Si nan...

Structural characteristics of phase transformations in epitaxial ferroelectric films are analyzed via a Landau–Devonshire thermodynamic formalism. It is shown that the phase transformation temperature, the lattice parameters, and the order of the phase transformation are a strong function of the misfit strain and are considerably different compared to unconstrained, unstressed single crystals o...

We grew epitaxial layers on 4H-silicon carbide (SiC) Si-face substrates with a 1° off-angle. The suppression of 3C-inclusion formation during growth at a high C/Si ratio was investigated, because a growth technique with a high C/Si ratio is needed to decrease residual nitrogen incorporation. 3C inclusions were generated both at the interface between the substrate and epitaxial layer, and during...