Metal interconnection structure, semiconductor device and method for improving performance of diffusion barrier layer

Abstract

The invention provides a metal interconnection structure, a semiconductor device and a method for improving the performance of a diffusion impervious layer. The metal interconnection structure comprises an interconnection metal layer, a passivation layer and the diffusion impervious layer, wherein the passivation layer is connected between the interconnection metal layer and the diffusion impervious layer; the diffusion impervious layer is a Co-based alloy layer; and the passivation layer is formed by processing the surface of the diffusion barrier layer by using plasma. According to the metal interconnection structure, the diffusion impervious layer is arranged to be the Co-based alloy layer, so that the resistivity of the diffusion impervious layer can be reduced, and meanwhile, more effective volume can be reserved for an interconnection line; and the Co-based alloy layer is subjected to plasma treatment by using special gas, so that a passivation layer is formed on the surface of the Co-based alloy layer, and the barrier property is improved.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a metal interconnection structure, a semiconductor device and a method for improving the performance of a diffusion barrier layer. Background technique [0002] As the device size reaches the process node of 5nm and below, the resistivity and thickness of the barrier layer material become the key factors affecting the resistance of the middle-end (MEOL) and back-end (BEOL) process interconnection lines, which seriously restricts the improvement of device performance. In the traditional process, Ta / TaN and Ti / TiN are mostly used as the diffusion barrier and adhesion layer, so as to ensure that the interconnection metal can grow without pores in the high aspect ratio via hole, the step coverage is good, and the metal ion is prevented from entering the dielectric layer. Medium diffusion, improved reliability and electromigration characteristics. At the same time, the thickne...

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Problems solved by technology

[0004] At present, a single-layer Co-based alloy can be used instead of the Ta / TaN double-layer structure, but when the Co-based alloy is used in the contact hole, after high temperature and long-term annealing, the barrier properties will be degraded, and the interconnection metal in the contact hole will easily react with the substrate. Spikes are formed, causing large leakage

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