Dislocations and dislocation reduction in space grown GaSb

Abstract

The behaviour of dislocations in GaSb crystals grown in space both from a stoichiometric melt (floating zone method, FZ) and a Bi solution (floating solution zone, FSZ) respectively, is studied. Predominantly straight 60° dislocations with Burgers vectors of the type b = a/2 <110> in (111) glide planes are identified. In the 20 mm long FZ single crystal the linear growing out of the dislocations is observed which reduces the dislocation density in the centre of the crystal to values below 300 cm . The Bi incorporation in the FSZ crystal results in a misfit between seed and grown crystal and in a network of misfit dislocations at the interface. Thermocapillary convection during growth as well as the surface tension may be the reasons for the presence of curved dislocations and the higher dislocation density within a 1 -2 mm border region at the edges of both of the crystals. Dedicated to Prof. Wolfgang Neumann on the occasion of his 65th birthday

Application of X-ray topography to USSR and Russian space materials science

“…In work by Kartavykh (2005), Kartavykh & Ginkin (2008) and Danilewsky et al (2009), the effect of microgravity on the growth of bulk InP(S) single crystals from a melt on board the ASV Foton-11 was investigated. The growth of crystals on board the satellite and on Earth (a reference crystal) was carried out by the travelling heater method.…”