Low temperature annealing process for relieving MOCVD TiN membrane stress and resistance

Abstract

The name in religion belongs to the integrated circuit craft manufacture area of technology, is concrete is a kind of MOCVD membrane withdraws from a mess the craft, eliminates the TiN membrane the stress, reduces the thin film resistance. Is opposite to the PCD technology, MOCVD TiN has the fine stair cover, but also has the obvious shortcoming, mainly is in the thin film includes higher C, impurity and so on O, may achieve 20%, the thin film quality of material is loose, when exposes when the air, as a result of the oxygen, the carbon dioxide and so on was mad the experience rapidly proliferates into the membrane the surface layer, creates the thin film resistance between to increase as necessary. The invention through to MOCVD TiN membrane after annealing processing, causes the thin film to have the heavy crystallization and the hot backflow, changes compactly, smoothness improvement; And gas and so on dependence nitrogen / hydrogen removes in TiN membrane C, impurity and so on O, thus gets up eliminates the TiN membrane stress, reduces the thin film resistance, causes the membrane nature to be stabler.

Description

technical field [0001] The invention belongs to the technical field of integrated circuit chip manufacturing technology, and in particular relates to a post-annealing process of a MOCVD TiN film, so as to eliminate the stress of the TiN film and reduce the sheet resistance. Background technique [0002] In the aluminum metal interconnect technology, the preparation of TiN barrier layer is a prerequisite for the preparation of W vias and Al films. This TiN layer not only prevents WFb and SIO 2 The reaction of the dielectric layer also enhances the adhesion of the tungsten plug, the Al metal film and the dielectric layer. The quality of the tungsten plug and the Al film has a direct impact on whether the tungsten plug and the Al film can be filled normally. [0003] At present, the preparation of TiN barrier layer is as follows: [0004] 1. PVD Ti / TiN barrier layer deposition technology. This technique mainly consists of the following 3 steps: [0005] 1) Degassing (degas)...

AI Technical Summary

Problems solved by technology

[0020] For PVD technology, the disadvantage of MOCVD TiN is that the film contains high C, O and other impurities, resulting in a 10-15% higher through-hole resistance.

The texture of the film is relatively loose, and the film quality is not stable. When exposed to the air, due to the O 2 , CO 2 Such gases will quickly diffuse into the surface of the film to form compounds, causing the sheet resistance to increase over time

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