Process for manufacturing metallized coating under wafer bump and coating structure thereof

Abstract

The invention discloses a process for manufacturing a metallized coating under a wafer bump and a coating structure thereof. A substrate in the process is a silicon or silicon carbide semiconductor; wherein a conductive circuit area and a non-conductive area are arranged on the surface of the substrate, and the conductive circuit area on the surface of the substrate sinks downwards to form an inverted wafer bump. The coating obtained through a chemical tin alloy plating process is a chemical replacement type coating, electrification is not needed, a traditional chemical auto-catalytic reactionis not needed, and only a replacement reaction is needed. The under bump metallization (UBM) and the redistribution line (RDL) obtained by the method provided by the invention not only can have binding property, but also have good weldability.

Description

technical field [0001] The invention relates to the technical field of integrated circuit packaging, in particular to a coating manufacturing process for metallization under wafer bumps and a coating structure thereof. Background technique [0002] With the increasing demand for high-performance and high-integration chips, the metal lines of the chip and its package are becoming smaller and smaller, so as to meet more I / O contacts and improve the computing performance of the chip. In particular, the RDL (redistribution) process of the fou-out process that has appeared in recent years has a line width and line spacing of 2 / 2 μm. [0003] The traditional advanced packaging is a flip-chip packaging process. The typical process is CSP (Chip Scale Package) packaging. The electrodes inside the chip are dispersed by RDL through the fan-in process, and then the balls are planted. This packaging and testing process is relatively traditional. Wire-bonded packaging saves a lot of spac...

AI Technical Summary

Problems solved by technology

However, as the lines become thinner and the spacing becomes smaller and smaller, the process of electroless nickel-gold plating is greatly challenged, because electroless nickel-plating gold is prone to permeation, resulting in short circuit of two independent lines, or easy to make independent Missing plating occurs on the pad

Although the electroplating process will not cause leaking and missing plating, the electroplating process requires all the lines to be interconnected, and it needs to have the function of electrification to realize it, which cannot meet the coating needs of independent pads

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