GaAs solution growth experiment in microgravity

We ran a GaAs solution growth experiment aboard the German sounding rocket TEXUS as a preliminary study for a Spacelab D-2 experiment. The experiment involved a growth technique that avoids surface-tension induced convection which destroys diffusion controlled growth, even in microgravity. We noted a remarkable difference in surface morphology between the space-grown crystal and an earth-grown reference crystal. Many hillocks and craters were found on the microgravity-grown crystal, but the surface of the earth-grown crystal was relatively flat. We discuss the growth mechanism under microgravity as compared to that under a lg condition.