A Low-Cost and Low-Temperature Method to Realize Carbon Nanotube Conductor in Through-Silicon-Via

Through-silicon-via (TSV) technology is the key to three-dimensional (3D) heterogeneous integration strategy. In this paper, a novel low-cost and low-temperature method to fabricate carbon nanotube (CNT) conductor in blind TSV is proposed. Based on a series of precise operations of the conductive water-based solution of metallic CNTs including coating, vacuum treatment, and spinning, dense CNTs are successfully filled into blind TSVs of various dimensions, which can serve as the TSV conductors. This method avoids the expensive and high-temperature processes to grow or transport CNT conductors in TSVs, and is compatible with other integration strategies. Moreover, together with the vacuum-assisted spin coating of polyimide (PI) liners, a low-cost and low-temperature fabrication flow for blind TSVs can be achieved. This work provides a promising method towards the fabrication and application of CNT based TSVs.