Epitaxial deposition of InGaAsP solid solutions in the miscibility gap

Liquid-phase epitaxy of InGaAsP solid solutions isoperiodic with (001)GaAs substrates was studied in the miscibility gap. At the initial stage of depo sition (first 1-2 s), thin (up to 0.15 mum) planar layers of homogeneous In GaAsP solid solutions are formed. This is aided by pronounced supercooling of the melt (by 10-15 degreesC) and the resulting high growth rates. In fur ther stages, growth becomes slower and a natural nanoheterostructure starts to form owing to decomposition of the solid solution. The formation of a n anoheterostructure comprising domains of different compositions with differ ent lattice constants is accompanied by the appearance of an undulating rel ief on the sample surface, with the undulation magnitude increasing as the layer grows. Under the technological conditions employed, the thickness of InGaAsP solid solution layers containing a nanoheterostructure is limited t o 0.5 mum. (C) 2000 MAIK "Nauka/Interperiodica".