Baganov Y. Control of the conditions of the heteroepitaxial growth from the liquid phase in the lattice misfit GaSb/InAs system

Object - crystallization processes under conditions of the differences of crystal and chemical parameters of the materials; objectives - determination of the necessary technological regimes and realization of the corresponding control of the growth conditions at heteroepitaxy of the thin planar layers in the lattice misfit GaSb/InAs system with the sharp interface from the liquid phase; methods - mathematical and computer simulation, photoluminescence, optical microscopy; novelty - for the first time it has been suggested to use gas flow for cooling of substrate and in this way to control epitaxial process from the liquid phase; it has been calculated that values of the contact supercoolings for the system of InAs substrate - Sb solution in Ga melt at 450 °С are 3,5 °С and 4,7 °С for (100) and (111) substrate orientations respectively; critical thicknesses of the dislocation network formation for the GaSb heteroepitaxial layer on the InAs substrate have been defined as 50 nm and 55 nm for the (100) and(111) substrate orientation respectively at the edge dislocations network and 70-75 nm for the both orientations for the inclined 60° dislocations network; for the first time it has been calculated the values of the necessary solution-melt supercoolings during epitaxy (5,8 °С and 7,8 °С for the (100) and (111) substrate orientation respectively) and growth rates (2,5-3,5 nm/s and 22-31 nm/s for the (100) and (111) substrate orientation respectively) that provide planar surface of the epitaxial layer at start epitaxy temperature of 450 °C; results - crystallization condition conditions have been calculated, corresponding technological regimes have been worked out, and planar InAs/GaSb heteroepitaxial layers have been deposited with the use of the pulse cooling of saturated solution-melt and with the use of suggested method of substrate cooling by the gas flow; area of use - technology of semiconductor heteroepitaxial structures of materials with the differences in crystal and chemical parameters.