In x Ga 1− x Sb bulk crystal was grown on a GaSb seed under a constant temperature gradient using a GaSb(seed)/InSb/GaSb(feed) sandwich sample. A GaSb feed was dissolved into the InGaSb solution to supply GaSb component during the growth. The temperature gradient in the solution was estimated from the indium composition profile in the grown crystal using the InSb–GaSb pseudo-binary phase diagram. In order to measure the growth rate, tellurium impurity striations were intentionally introduced into the crystal by thermal-pulse technique. The growth rate gradually increased to the constant value and then rapidly decreased. The change of growth rate was reflected in the indium composition profile. Homogeneous In 0.03 Ga 0.97 Sb was grown by cooling the sample at the optimized value estimated from the temperature gradient and the growth rate.