Control system and control method for diameter of single crystal ingot
The embodiments of the present invention provides a diameter controlling system of the single crystal ingot for controlling a diameter deviation of a silicon ingot during the growth of silicon ingot by a Czochralski method, it may include a seed chuck for supporting a silicon ingot combined with a seed crystal and grown; a measuring part connected to an upper surface of the seed chuck with a cable and configured to measure a load applied to the seed chuck; a load adjusting part for moving a position of the seed chuck vertically while the seed chuck is connected to the cable to change a load applied to the silicon ingot; and a controlling part for controlling the load applied to the silicon ingot by driving the load adjusting part according to the load value measured from the measuring part. Therefore, shaking of the seed during the growth process of the single crystal ingot is prevented, and thus the diameter deviation of the growing single crystal ingot may be reduced.
1. A diameter controlling system of a single crystal ingot as a system of controlling a diameter deviation of the silicon ingot during growth of the silicon ingot by a Czochralski method, the system comprising:
a seed chuck configured to support a silicon ingot which is combined with a crystal seed and grown;
a measuring part connected to the upper surface of the seed chuck with a cable and configured to measure a load applied to the seed chuck;
a body part connected to surround the seed chuck;
a load adjusting part configured to move a position of the body part vertically while the seed chuck is connected to the cable and change the load applied to the silicon ingot; and
a controlling part configured to drive the load adjusting part according to a load value measured from the measuring part and control the load applied to the silicon ingot,
wherein the load adjusting part includes a support unit coupled to an upper surface of the body part, a lead screw having a threaded surface coupled to the support unit, and a linear motion (LM) guide for linearly raising or lowering the support unit coupled to the lead screw in accordance with a rotation direction of the lead screw.
2. The system of claim 1 , wherein the load adjusting part is coupled to be fixed in a process chamber, and two or more load adjusting parts are positioned so as to be connected to the seed chuck in directions opposite to each other.
3. The system of claim 1 , wherein a motor is provided on an upper portion of the lead screw, and the controlling part adjusts a location of the support unit by controlling a rotation direction and an amount of rotation of the motor.
4. The system of claim 1 , wherein the body part is formed in cylindrical shape to surround the seed chuck, and with a center portion formed to be penetrated.
5. The system of claim 4 , wherein the support unit is coupled to the upper end portion of the body part and the position of the body part is changed by the upward or downward movement of the support unit, and the load applied to the seed chuck is changed.
6. The system of claim 4 , wherein a bearing is formed on a surface at which the seed chuck and the body part are in contact with each other, and the seed chuck is rotated.
7. The system of claim 1 , wherein an input part configured to set a target value of a target ingot load by the user is further included, and the controlling part sets a load applied to the silicon ingot to the target value input to the input part.
8. The system of claim 7 , wherein the target value is set to a weight corresponding to the second half of the growth of the ingot in which the diameter deviation is relatively reduced with reference to the diameter deviation profile of the single crystal ingot grown in the previous run in the same ingot growing apparatus.
9. The system of claim 7 , wherein the controlling part unit compares the target value which is set by the user and a measured value in the current silicon ingot and drives the load adjusting part until the target value is equal to the measured value.