Abstract: A method for producing a nitrogen-doped single crystal silicon ingot includes, after cutting a reference ingot into sample silicon wafers, selecting a plurality of silicon wafers to be tested and evaluating a distribution of defect areas in the plurality of silicon wafers, wherein the defect areas comprise any of a pure vacancy area, a pure interstitial area, and an alternating distribution area of a pure vacancy area and a pure interstitial area. The method also includes determining a distribution position of each defect area in the reference ingot based on the distribution of the defect areas in the plurality of silicon. Then, in a production process of the nitrogen-doped single crystal silicon ingot, a pulling is performed at a set target pulling speed corresponding to each defect area which refers to the distribution position of each defect area in the reference nitrogen-doped single crystal silicon ingot.

Abstract: A method is for positioning a center of a V-type notch of a wafer. The method includes: determining, based on collected edge data of a V-type notch of a wafer, a center of a concentric circle corresponding to edges of the V-type notch; and judging, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position. The method also includes determining, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position; and driving, according to the rotation direction and rotation angle of the wafer, the wafer to rotate until the V-type notch is rotated to the preset target center position.

Abstract: A method for producing a nitrogen-doped single crystal silicon ingot includes, after cutting a reference ingot into sample silicon wafers, selecting a plurality of silicon wafers to be tested and evaluating a distribution of defect areas in the plurality of silicon wafers, wherein the defect areas comprise any of a pure vacancy area, a pure interstitial area, and an alternating distribution area of a pure vacancy area and a pure interstitial area. The method also includes determining a distribution position of each defect area in the reference ingot based on the distribution of the defect areas in the plurality of silicon. Then, in a production process of the nitrogen-doped single crystal silicon ingot, a pulling is performed at a set target pulling speed corresponding to each defect area which refers to the distribution position of each defect area in the reference nitrogen-doped single crystal silicon ingot.

Abstract: A method is for positioning a center of a V-type notch of a wafer. The method includes: determining, based on collected edge data of a V-type notch of a wafer, a center of a concentric circle corresponding to edges of the V-type notch; and judging, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position. The method also includes determining, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position; and driving, according to the rotation direction and rotation angle of the wafer, the wafer to rotate until the V-type notch is rotated to the preset target center position.