Plasma etching method, device thereof and plasma etching method for diffusion barrier layers

Abstract

The invention provides a plasma etching method, a device thereof and a specific method applying the device to carry out plasma etching on diffusion barrier layers, wherein the plasma etching method includes the following steps: an outer electrode collar and an inner electrode collar are concentrically arranged in an etching chamber; a semiconductor wafer to be etched is arranged on the bottoms of the outer electrode collar and the inner electrode collar, and the center of the semiconductor wafer is superposed with the circle center of the outer electrode collar and the inner electrode collar; etching gas is filled into the etching chamber; the outer electrode collar and the inner electrode collar are electrified, and the current directions of the outer electrode collar and the inner electrode collar are opposite. The invention ensures that the distribution of the plasma gas of the surface of the semiconductor wafer is uniform and the etching rate at each position is equal, thus improving the thickness consistency of each diffusion barrier layer at each position on the semiconductor wafer.

Description

technical field [0001] The present invention relates to the technical field of semiconductors, and more specifically, the present invention relates to a plasma etching method and device thereof, and a plasma etching method of a diffusion barrier layer. Background technique [0002] In the metal interconnection process, interconnection metals such as copper, aluminum or tungsten need to be filled in the interconnection structure (including trenches, contact holes, etc.). In order to prevent the above-mentioned metals from diffusing into the surrounding insulating dielectric layer, causing the insulation performance of the dielectric layer to decrease, and further generating leakage current, it is necessary to form a diffusion barrier layer on the inner wall of the trench and contact hole before conducting conduction. metal filling. Conventional diffusion barrier materials include metals or alloys containing tantalum and titanium, which can be a single-layer metal layer or a ...

AI Technical Summary

Problems solved by technology

[0011] The purpose of the present invention is to provide a plasma etching method and its device, which are applied to the manufacture of diffusion barrier layers, so as to solve the problem of inconsistency in the thickness of the diffusion barrier layer caused by the difference in etching rates in various places on the semiconductor wafer, which in turn leads to metal interconnection. Differences in the resistance of various parts of the structure, resulting in product reliability problems

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