2results about How to "Reduce defect level" patented technology

This invention discloses a laser powder bed additive manufacturing method and equipment. The laser powder bed additive manufacturing method includes: laying powder material on a substrate in a forming chamber; purging the forming chamber; scanning and printing on the powder material according to a preset laser scanning path, melting the powder material along the preset laser scanning path; wherein the preset laser scanning path includes moving in a first direction while oscillating in a second direction, the first direction intersecting the second direction; after printing, annealing and cutting the molten powder material to obtain a part. This invention can effectively change the internal flow state of the molten pool, reduce the formation of internal defects in the part, and improve the efficiency of laser scanning printing.

This invention relates to a high-efficiency polishing slurry for silicon wafers using a synergistic silica sol, which is mainly composed of the following raw materials in the indicated weight ratios: 10-30 parts silica abrasive; 0.001-0.5 parts nitrogen-containing functional group promoter; 0.01-1 part surfactant; 0.1-5 parts acid-base adjuster; and 30-90 parts water. This polishing slurry, through the synergistic effect of the compound design of amino silica sol raw materials and the interfacial reaction regulation mechanism of the nitrogen-containing functional group promoter, effectively improves the material removal rate, significantly improves polishing uniformity, inhibits local over-corrosion and particle agglomeration, reduces surface roughness, and simultaneously reduces particle residue and metal ion contamination. It achieves a synergistic balance between high efficiency and low damage, meeting the performance requirements of polishing slurries for precision machining of high-end single-crystal silicon wafers.