We perform specific research on the growth of silicon crystals by the Czochralski technique with respect to higher yield and improved material quality. For example we push the pull speed to its limit by optimization of the hot zone using numerical modeling or we unlock the secrets of the growth ridge in order to detect defect formation during crystal pulling. In the field of directional solidification emphasis is put on technology development and characterization of the Si ingots to be used for example as sputter targets or as mechanical components in the semiconductor industry.