Interconnection electromigration test structure

Abstract

The invention provides an interconnection electromigration test structure which comprises a to-be-tested structure, a lead structure, n layers of electric conduction structures and dielectric media. The lead structure comprises a first lead and a second lead. The n layers of electric conduction structures are sequentially stacked from top to bottom, and are placed on the lower layers of the to-be-tested structure and the lead structure. Every layer of electric conduction structure comprises a first through hole structure, a first connection structure, a second through hole structure, a third through hole structure, a second connection structure and a fourth through hole structure, wherein n is a positive integer which is greater than or equal to two. The to-be-tested structure, the first lead, the second lead, the first through hole structure, the first connection structure, the second through hole structure, the third through hole structure, the second connection structure and the fourth through hole structure are insulated and spaced through the dielectric media, wherein the first through hole structure, the first connection structure, the second through hole structure, the third through hole structure, the second connection structure and the fourth through hole structure are placed on every layer of electric conduction structure. The interconnection electromigration test structure can accurately assess electromigration of the to-be-tested structure, and so that the accuracy of electromigration analysis of the to-be-tested structure can be guaranteed.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to an interconnect electromigration test structure. Background technique [0002] Electromigration (EM for short) is a phenomenon of material transfer caused by the gradual movement of atoms in a conductor, and its internal mechanism is the transfer of momentum between conductive electrons and diffused metal atoms. For applications with high direct current densities, such as in the field of microelectronics, the electromigration effect is very critical. Electromigration occurs when part of the momentum of a moving electron is transferred to a nearby activated atom, which causes the atom to leave its original position. Over time, this force causes huge numbers of atoms to move away from their original positions. Electromigration can cause breaks or gaps in conductors (especially narrow wires) to prevent current flow. Such breaks or gaps are called voids or inter...

AI Technical Summary

Problems solved by technology

[0004] However, since the feature size of integrated circuits is getting smaller and smaller, especially when it is below 45nm, the thickness of the lower-layer interconnection is getting thinner and thinner, and the gap between the thickness of the upper-layer interconnection and the thickness of the lower-layer interconnection in the interconnection is getting larger and larger. , so that the interconnection electromigration test structure in the prior art has been unable to truly measure the electromigration of the structure to be tested 110, such as figure 1 As shown, in the interconnection electromigration test structure in the prior art, voids are generated in the underlying interconnection line where the connection structure contacts the via structure, for example, due to the cross-sectional area of ​​the third via structure 133 limited, so the current density at the second connection structure 142 close to the third via structure 133 is relatively high, and voids are generated in the region b of the second connection structure 142 close to the third via structure 133, like figure 1 As shown, it is impossible to accurately measure the electromigration of the structure under test 110

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