A perimeter millimeter-level eutectic element welding device and welding method

Abstract

The invention discloses a perimeter millimeter-level eutectic element welding device, comprising a bottom plate, wherein the bottom plate surface is provided with a group of rectangular positioning grooves, the rectangular positioning grooves comprise an upper positioning groove and a lower positioning groove which are connected to form a step groove, and the lower positioning groove is used for accommodating a ceramic substrate. The welding device also comprises a positioning plate and a pressing plate, wherein the positioning plate can be embedded in the upper positioning groove, a group ofpositioning holes on the surface of the positioning plate, and the positioning holes are distributed according to the positions of the components to be welded. A set of pressing blocks is arranged onthe bottom surface of the pressing plate, and the pressing blocks are matched with the positioning holes one by one. The eutectic welding is completed through the steps of pretreatment, obtaining of the welding sheet, placing of the substrate, placing of the components to be welded, eutectic sintering, taking the parts, placing of the bonding transition piece, eutectic sintering of the bonding transition piece, taking the parts and cleaning. The invention realizes that all bonding transition wafers or semiconductor die after welding are flat and uniform in height, meets the requirements of welding inspection and bonding process, and improves the yield of thick wire bonding.

Description

technical field [0001] The invention relates to the technical field of microelectronic assembly, in particular to a eutectic welding device and a welding method for millimeter-scale components with perimeters. Background technique [0002] In the microelectronics assembly process, there are two main methods for assembling semiconductor chips and surrounding circuits on desired carriers (such as ceramic substrates, shells, etc.) and eutectic sintering. . Among them, conductive adhesive bonding has the advantages of simple process, fast speed, low cost, and repairability, and low-temperature bonding has no special requirements for metallization on the back of the die. However, when the product has a high power requirement, due to the high resistivity and high thermal conductivity of the conductive adhesive, the loss is large, the thermal resistance of the power die is large, and the junction temperature is high, and its power performance and reliability will be affected. [...

AI Technical Summary

Problems solved by technology

However, manually spotting solder paste cannot make the solder surface smooth and the solder height consistent. After heating to the soldering temperature, high temperature resistant materials must be used to flatten the bonding transition pieces one by one and ensure the flatness of the bonding transition pieces after welding to meet Welding inspection and thick wire bonding have technical requirements for flatness, and in the welding process, due to the large number of bonding transition pieces, and the shrinkage of the solder itself under the effect of surface tension will cause the transition piece floating on the solder to occur. When moving and adjusting the transition piece, you can't look at each other from head to tail, and be comprehensive

Therefore, it is difficult to guarantee that all bonding transitions will remain flat after soldering

The unevenness of the bonding transition piece will lead to a significant increase in bonding rework, and even some circuits will be scrapped because the number of rework at the same position exceeds the relevant regulations of the national military standard twice.

[0005] In addition, in the process design, in order to improve the power performance and reliability of the product, the semiconductor die with a circumference of millimeters and small size generally adopts the soldering process. Same problem with the transition piece

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