Crystal growing apparatus with charge-centric opening, and apparatus and method for controlling the heat extraction from a crucible

A crystal growing apparatus comprises a crucible which is arranged on a holding mechanism, and at least two plates which are formed below the holding mechanism and are movable in a coordinated manner to form a symmetrical opening with respect to an ingot, which is formed in the crucible is centered, and a drive mechanism for controlling the plates with one degree of freedom. The plates are opened in a plurality of discrete positions, to form an opening with respect to the ingot being formed, the charge is centered in order to promote directional solidification which is formed of the ingot, and thus a desired convex profile to reach the ingot.