BRIDGMAN SOLIDIFICATION OF GASB IN SPACE

Two samples of GaSb and Ga1-xInxSb (x = 0.001) have been grown in roug h crucibles in space and full detachment of the sample from the crucib le was obtained over a large part of the crystals. Due to problems wit h the control system of the space furnace both seeds were molten and t he growth began with polycrystals. As the growth proceeded, one grain was selected in each sample and the growth finished with a single crys tal. X-ray analysis has shown that, in the zone where there was no con tact with the crucible, the structural quality continuously improved. Chemical segregation obtained in space is representative of a diffusiv e regime of transport in the melt, in spite of the low growth rate use d. This differs from ground experiments which are under convective con ditions. Measurements of electrical properties have given results comp arable to that of standard samples obtained on earth, but with a rathe r lower electrical resistivity. (C) 1998 Elsevier Science B.V. All rig hts reserved.