A method for preparing a high-entropy alloy diffusion barrier layer for Cu interconnection integrated circuits

Abstract

The invention relates to the technical field of semiconductor integrated circuits, in particular to a high-entropy alloy diffusion barrier layer for a Cu interconnect integrated circuit and a preparation method of the high-entropy alloy diffusion barrier layer for the Cu interconnect integrated circuit. The high-entropy alloy diffusion barrier layer for the Cu interconnect integrated circuit sequentially comprises a Si substrate layer, a high-entropy alloy intermediate coating and a Cu film from bottom to top, wherein the high-entropy alloy intermediate coating sequentially comprises a third coating, a second coating and a first coating from bottom to top; the first coating is an AlCrTaTiZrMo high-entropy alloy coating; the second coating is a pure Ti coating; and the third coating is an AlCrTaTiZrMoNx high-entropy alloy coating. According to the high-entropy alloy diffusion barrier layer for the Cu interconnect integrated circuit, improvement of the atomic bulk density is facilitated,generation of defects, such as vacancies is reduced, a diffusion channel for atoms is reduced, and the diffusion barrier performance and the heat stability of the high-entropy alloy coatings are improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductor integrated circuits, and in particular relates to a Cu interconnected integrated circuit high-entropy alloy diffusion barrier layer and a preparation method thereof. Background technique [0002] With the improvement of integrated circuit integration and the continuous decrease of feature size, Cu can be used as a metal interconnect material due to its low resistivity and high electromigration resistance, replacing the traditional Al interconnect material, thereby reducing the RC delay problem. However, the adhesion between Cu and the dielectric layer is poor, and Cu is easy to diffuse into Si and SiO 2 In the dielectric layer, a copper-silicon compound is formed and becomes a deep-level impurity, thereby affecting the reliability, stability, and transmission efficiency of the device. Therefore, in order to prevent the diffusion between Cu and Si, a diffusion barrier layer with high thermal...

AI Technical Summary

Problems solved by technology

Although the existing transition group refractory metals, ternary nitride coatings and laminated structures have achieved good results, however, with the further shrinking of the size of integrated circuits, it is required that the barrier layer should be as thin as possible while maintaining a relatively small thickness. Good barrier properties, low resistivity and high thermal stability

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