Bridgman solidification of GaSb in space

Two samples of GaSb and Ga1-xInxSb (x = 0.001) have been grown in rough crucibles in space and full detachment of the sample from the crucible was obtained over a large part of the crystals. Due to problems with the control system of the space furnace both seeds were molten and the growth began with polycrystals. As the growth proceeded, one grain was selected in each sample and the growth finished with a single crystal. X-ray analysis has shown that, in the zone where there was no contact with the crucible, the structural quality continuously improved. Chemical segregation obtained in space is representative of a diffusive regime of transport in the melt, in spite of the low growth rate used. This differs from ground experiments which are under convective conditions. Measurements of electrical properties have given results comparable to that of standard samples obtained on earth, but with a rather lower electrical resistivity. (C) 1998 Elsevier Science B.V. All rights reserved.