Epitaxial lateral overgrowth was performed on {001}-oriented InP substrates by liquid phase epitaxy at a constant growth temperature of 450 to 650C. Here, so-called line and space and L-shaped patterns were formed on the substrates before epitaxy, and the as-grown and etched surfaces were then observed by Nomarski interference optical microscopy. Defect etching revealed dislocation etch pits on both the open seed areas and the coalescence regions of the epitaxial lateral overgrowth layer formed on the line and space patterns. However, when using the L-shaped pattern, etch pits were observed only on the open seed regions of the epitaxial lateral overgrowth layer. It was shown that the epitaxial lateral overgrowth layers that spread laterally inside the L-shaped pattern were dislocation-free. In addition, large-area epitaxial lateral overgrowth layers were obtained when the L-shaped pattern was modified by rotating the direction in which it was facing. In the case of the L-shaped pattern, the optical properties of the epitaxial lateral overgrowth layer were improved as compared with those on the open seed area.

Dislocation-Free Large Area InP ELO Layers by Liquid Phase Epitaxy. T.Kochiya, Y.Oyama, T.Kimura, K.Suto, J.Nishizawa: Journal of Crystal Growth, 2005, 281[2-4], 263-74