Method for micropore filling by using CTAB as inhibition additive

Abstract

The invention provides a method for micropore filling by using CTAB as an inhibition additive. The CTAB is adopted as an inhibition additive, a pure copper plate is immersed in an electroplating solution to serve as an anode, a silicon wafer containing micropores is immersed in the electroplating solution to serve as a cathode, and the micropores of the silicon wafer are electroplated and filled.Compared with a traditional inhibition additive electroplating system, the filling method using the CTAB as the inhibitor has a stronger inhibition effect on the pore openings and the side walls of the micropores, is higher in transport capacity, better in electroplating filling effect and higher in efficiency, is beneficial to saving the micropore electroplating filling cost, and has great advantages in high-aspect-ratio micropore electroplating filling.

Description

technical field [0001] The invention relates to the technical field of micropore filling, in particular to a method for micropore filling using CTAB as an inhibitory additive. Background technique [0002] As the size of integrated circuits becomes smaller and more integrated, the number and density of interconnection wires between components on a chip increase dramatically. The 3D integrated packaging technology with Through Silicon Via (TSV) micro-channel interconnection as the core has become an inevitable choice. A typical TSV has a diameter of a few microns to tens of microns, an aspect ratio of 3:1 to 20:1, and usually uses copper as a filler. Due to the limitations of the TSV structure, there are great challenges in the fabrication process. The TSV filling process is complex and technically difficult, and it is easy to form filling defects such as holes and gaps, and the manufacturing cost remains high. [0003] A typical solution to address TSV filling defects is ...

AI Technical Summary

Problems solved by technology

This method has a good effect in low aspect ratio TSV filling, but it is difficult to avoid filling defects in high aspect ratio TSV filling

[0004] The main reason for this situation is that the inhibition of traditional inhibitory additives on the bottom of TSV is "strong but not strong": (1) The current TSV filling process generally uses the traditional electroplating process, while the traditional macromolecular inhibitor ( Such as PEG, PEI), usually has a relatively large molecular weight (Mr 5000 or more), and has limited transport capacity in the deep region of TSV, and cannot be effectively transported to the bottom of the deep hole to inhibit the growth of copper plating, that is, "strong but not to"; (2 ) Traditional small molecule leveling agents (such as JGB), although the molecular weight is small (Mr511), can be transported to the bottom area of ​​deep pores, but the inhibition performance is weak, that is, "to not strong"

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