A method for controlled growth of silicon carbide and structures produced by the method are disclosed. A crystal of silicon carbide (SiC) can be grown by placing a sacrificial substrate in a growth zone with a source material. The source material may include a low-solubility impurity. SiC is then grown on the sacrificial substrate to condition the source material. The sacrificial substrate is then replaced with the final substrate, and SiC is grown on the final substrate. A single crystal of silicon carbide is produced, wherein the crystal of silicon carbide has substantially few micropipe defects. Such a crystal may also include a substantially uniform concentration of the low-solubility impurity, and may be used to make wafers and/or SiC die.