Interconnecting structure for enhancing stress migration reliability

Abstract

The invention provides an interconnecting structure for enhancing stress migration reliability, belonging to the technical field of integrated circuits, comprising: a metal 1 and a metal 2 electrically connected with each other, wherein the width of the metal 1 is larger than the width of the metal 2; a plurality of grooves are arranged in the metal. The invention has the advantages that the totalvacancy content in the interconnect structure is relatively reduced due to the existence of grooves; a large tensile stress gradient exists in the vicinity of the groove, and a large number of vacancies in the metal 1 will accumulate in the vicinity of the groove, especially in the dense region of the groove; the tensile stress gradient at and near the contact interface between metal 1 and metal2 is reduced, the tensile stress gradient at and near the contact interface between a via hole and the metal 1 is reduced, and the migration velocity of vacancy to the key position is reduced. Therefore, the present invention reduces the amount of vacancies that can migrate to key locations and the migration speed of the vacancies, thereby improving stress migration reliability.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to an interconnect structure for enhancing stress migration reliability. Background technique [0002] Currently, stress migration is one of the main mechanisms leading to the failure of integrated circuit interconnect lines. During use, metal grain growth within the wires releases a large number of grain boundaries, creating vacancies. The mechanical stress gradient is the main factor leading to the accumulation and growth of vacancies, which in turn leads to failure. With the development of multi-layer, miniaturized, and complex wiring, and the use of new materials such as low dielectric constant and alloy cap layer, the stress distribution and mass transport mechanism of the interconnection structure become more and more complicated. Therefore, in advanced manufacturing processes, it is very important to study how to suppress stress migration failure by improving st...

AI Technical Summary

Problems solved by technology

When the width difference between the two is large, there is a large tensile stress gradient between the wide and narrow metals, which leads to the migration and accumulation of a large number of vacancies in the wide metal to the narrow metal or the bottom of the via hole at a faster speed, resulting in a larger gap. Large risk of stress migration failure

[0004] At present, there is no report on suppressing this type of failure by improving the stress gradient distribution

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