LONG-TERM CRYSTAL-GROWTH UNDER MICROGRAVITY DURING THE EURECA-1 MISSION .2. THM GROWTH OF SULFUR-DOPED INP

Long-term crystal growth experiments were successfully performed under microgravity conditions during the first flight of the unmanned EUREC A-1 mission in the automatic mirror furnace (AMF). Two crystals of sul phur-doped InP with [001] and [111] orientation respectively were grow n from indium solution by the travelling heater method (THM). The abse nce of time dependent buoyancy-driven convection is documented by the lack of type I striations in the space-grown crystals. The sulphur con centration is measured by spatially resolved photoluminescence. As exp ected, the macrosegregation can be described by a pure diffusion-contr olled model which is in good agreement with the findings from the firs t German spacelab mission D1. Compared to the earth-grown reference sa mples, both of the space-grown InP crystals show strong disturbances s uch as inclusions and type II striations. The morphological instabilit ies are similar to growth disturbances already known from the space-gr own MD-ELI-01 from the D1 mission.