Sub-ingot silicon rod with technology protection ends and production method

Abstract

The invention discloses a sub-ingot silicon rod with technology protection ends and a production method. The sub-ingot silicon rod with technology protection ends is composed of a silicon slice cutting section and technology protection sections arranged at two ends of the silicon slice cutting section. Because the technology protection sections are arranged at two ends of the sub-ingot silicon rod to be sliced in advance, during the cutting process, the technology protection ends arranged at two ends of the sub-ingot silicon rod can protect the outermost silicon slices, and no conditions of slice falling, corner missing, edge breaking and the like happen. Breakage of cutting steel wires caused by slopes of two ends of the sub-ingot silicon rod can be avoided during the cutting process of silicon slices, conditions of slice cracking, corner missing, edge breaking and the like of outermost silicon slices can be prevented effectively, and the slice output rate of silicon rods and the qualified rate of silicon slices are ensured.

Description

Technical field: [0001] The invention relates to a polycrystalline silicon rod used for cutting polycrystalline silicon wafers, in particular to a polycrystalline silicon rod which prevents wire cutting wires of silicon wafers from breaking and improves the qualified rate and yield of silicon wafers. technical background: [0002] Solar polysilicon wafers are the most basic raw materials for solar cells. The existing production method of polysilicon wafer is multi-wire cutting. Before processing polycrystalline silicon wafers, the silicon ingot is first cut into squares to obtain a sub-ingot with a square cross section, and then the minority carrier life of the square sub-ingot is tested, and the part with a low minority carrier life at both ends of the square sub-ingot (that is, the invalid length part) ) to obtain sub-ingot silicon rods, and finally bond the sub-ingot silicon rods to the workpiece plate. The bonding structure is as follows figure 1 As shown, the sub-ingo...

AI Technical Summary

Problems solved by technology

During the processing, when the silicon wafers located at both ends of the sub-ingot are at the beginning of cutting or near the end of cutting, they are prone to chipping, missing corners, and chipped edges due to the impact of mortar. The slope at a certain angle leads to uneven thickness of the silicon wafers located at both ends of the sub-ingot. During the cutting process, due to the uneven thickness of the silicon wafers, the steel wire is stressed unevenly. Therefore, it is easy to cause the cutting steel wire to break when cutting here Even if the cutting wire is not broken, the damage rate of the silicon wafers at both ends is relatively high. Usually, more than 10 defective silicon wafers are produced for each cut, which not only affects the yield of silicon rods, but also affects the cutting quality of the cut silicon wafers. , at the same time increases the downtime wiring time, for the high quality requirements of the silicon wafer cutting the whole roll of steel wire will be scrapped

If a vertical glass plate 4 is not added to the exposed end of the sub-ingot silicon rod 1, the number of defective silicon wafers produced per cut will be greater

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