Growth kinetics in space- and earth-grown InP and GaSb crystals

Sulphur-doped InP and tellurium-doped GaSb have been grown by the travelling-heater method from indium and gallium solutions under microgravity and earth conditions. To analyse the growth kinetics on a microscale, time markers were generated during the crystal growth. This is done by rotating the samples and by pulsing the lamp of the mirror-heater. In space grown crystals as well as in the earth grown reference samples, type II striations as traces of macrosteps occured at the beginning and the end of THM growth. It can be shown, that there is a critical growth velocity for macrostep formation. The onset of macrosteps is also influenced by the properties of the seed crystal.