A coaxial bicyclic TSV structure with low thermal stress and high electrical performance and preparation method thereof

Abstract

The invention discloses a coaxial double-ring TSV structure with low thermal stress and high electrical performance and a preparation method. First, the wafer is thinned to a required thickness; then a TSV through hole is formed on the front side of the wafer; and then the inner wall of the TSV through hole is formed The first insulating layer is deposited by thermal oxidation method and deposition method; the diffusion adhesion layer / barrier layer, the seed layer and the outer conductive metal ring are sequentially prepared on the inner wall of the first insulating layer; the diffusion adhesion layer / barrier is deposited on the inner side of the outer conductive metal ring layer, the second insulating layer; prepare the diffusion adhesion layer / barrier layer, the seed layer and the inner conductive metal ring on the inner wall of the second insulating layer; deposit the diffusion adhesion layer / barrier layer in the inner conductive metal ring, and fill the third insulating layer , the coaxial double-ring TSV structure is obtained. The outer conductive metal ring of the present invention is grounded to shield signal interference, and the inner conductive metal ring is used to transmit signals and reduce thermal stress.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing technology, relates to a preparation technology of a semiconductor TSV structure, and in particular relates to a coaxial double-ring TSV structure with low thermal stress and high electrical performance and a preparation method. Background technique [0002] In the process of manufacturing TSVs in the prior art, the TSVs and silicon wafers need to undergo many thermal cycles, and the final annealing and cooling process will bring huge temperature loads to the entire structure. , the difference in yield strength produces great thermal stress and thermal strain around it, which affects the carrier mobility and device performance and reliability. Therefore, it is necessary to study the thermomechanical properties of TSVs. In addition, TSVs are essentially metal lines that pass through a silicon substrate, and a layer of isolation dielectric (such as silicon dioxide) is generally ...

AI Technical Summary

Problems solved by technology

The MOS capacitance of this structure will cause the signal on the TSV to couple to the silicon substrate or the surrounding devices, resulting in signal distortion and leakage current, increasing static power consumption, so a new one that can avoid thermal stress and have high electrical performance is required. TSV technology

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