A method for producing a crystallized compound semiconductor material comprises synthesizing said material by fusion and inter-reaction of its constituents placed in elementary form constituting a charge into a sealed ampoule, and then crystallizing the resulting material in liquid form by cooling. Also including: increasing, within the charge, proportion of one constituent beyond the stoichiometric proportions of the material, thereby defining an excess of the one constituent; subjecting the entire sealed ampoule to a temperature higher than or equal to fusion temperature of the material; subjecting the ampoule to a low temperature gradient and to a gradual drop in temperature, to induce crystallization of the resulting material in liquid form, in stoichiometric proportion; subjecting part of the ampoule where the crystallized material is not present, to a significant drop in temperature modifying vapor pressure state of the excess to a saturated vapor state; and cooling the whole assembly down to ambient temperature.