A method to ensure consistent grain orientation of butt single crystal solder joints

Abstract

The invention provides a method for ensuring consistent crystal orientation of butt-joint single-crystal welding spots, and belongs to the field of material preparation and connection. The method comprises the steps that oxide and organic pollutants on the surfaces of bonding pads are removed, double-sided adhesive tape adheres to a substrate, the two bonding pads are placed on the substrate, the welding surfaces are parallel to each other and are spaced, brazing filler metal soldering paste is applied to be position between the welding surfaces, and re-melting and cooling are carried out to obtain a brazing filler metal butt joint; the brazing filler metal butt joint and the substrate are placed in an acetone solution, the brazing filler metal butt joint is taken down from the substrate, inlaying does not need to be carried out, grinding is directly carried out to remove the excess brazing filler metal, and the surface, capable of serving as the cross section, of the brazing butt joint is polished; observation is carried out on a PLM, and the brazing butt joint with single-crystal orientation is selected under the PLM; and linear cutting is carried out on the obtained brazing filler metal single-crystal butt joint so as to obtain a plurality of miniature brazing butt joints, and fine polishing is carried out on the obtained miniature brazing butt joints so as to obtain EBSD data. The method has the beneficial effects that the size of the brazing butt joint can be controlled, and the consistency of the crystal orientation of the butt joint can be ensured.

Description

technical field [0001] The invention is a method for ensuring consistent grain orientation of butt single crystal solder joints, belongs to the field of material preparation and connection, is suitable for preparing micro-brazed butt joints with consistent grain orientation, and is applied to the mechanics, heat and electricity of microelectronic connections reliability research. This process can effectively ensure the size and grain orientation of solder joints, thereby ensuring the comparability of reliability test data of brazed butt joints. Background technique [0002] Solder joints are an integral part of microelectronic interconnection, playing the role of mechanical connection and electrical signal transmission. At present, the microelectronic packaging space is reduced, and the heat generation of the chip is intensified. On the one hand, the intermetallic compounds (Intermetallic Compounds, IMCs) generated by the reaction between the solder and the pad metallizatio...

AI Technical Summary

Problems solved by technology

At present, it is a thermodynamic problem to deeply understand and predict the growth mode of Sn dendrites. After the interconnection is completed, each solder joint has a unique crystal orientation, so it is inevitable that there will be some solder joints due to the growth of β-Sn grains. Unfavorable orientation, premature failure during the use of electronic products, thereby reducing the service life of electronic products

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