Comparative Ground Experiment of GaSb:Te Melt Growth to the Space Experiment by Chinese Recoverable Satellite

抄録

In order to confirm the effect of the micro-gravity on the distribution of impurity in the space grown crystal, Te doped GaSb single crystal was re-grown by vertical gradient freeze method (VGF) under terrestrial condition. Te con­ centration distribution in the re-grown GaSb crystal was measured by spatially resolved photoluminescence (SRPL) and it was found that the concentration profile was rather close to the calculation based on the complete mixing model. The cross section was investigated after striation etching and it was found that clear impurity striations appeared in the later part of the crystal. In contrast to the previous space experiment where Marangoni convection as well as the thermal convection were eliminated, it was confirmed that strong buoyancy driven convection was found to exist in the melt during the growth experiment under terrestrial condition.