TSV Filling with Copper Electro-deposition by Using Sodium 3-[[(dimethylamino) thioxomethyl] thio] Propane Sulphonate

Abstract

Through Silicon Via (TSV) is a promising microelectronic interconnection technology in Three-D integration (3D). Three-component additives are used for non-porous TSV filling. However, various experiments must be carried out to optimize the concentrations of various additives. To avoid this costly process, Two-component additives were developed. In this paper, Sodium 3-[[(dimethylamino) thioxomethyl] thio] propane sulphonate (DPS) in the TSV filling is investigated. Only by DPS in TSV copper sulfate plating, copper ions cannot reach the bottom of the micro-hole, and copper deposits at the TSV orifice. The addition of dimethyl formamide based on the structure of MPS enhances the inhibition of DPS and may show a weak inhibition during the copper plating and filling process of TSV. 0.1 g/L DPS and 1 g/L AESS, with ampere density2 mA/cm2 and a plating time of 12 h, can obtain perfect defect-free TSV filling.