The real demonstration of High-Quality Carbon Nano-Tubes (CNTs) as the electrical connection for the potential application in a vertical 3D integrated technology

High-quality and the large area Carbon Nano-Tube (CNTs) is grown by Chemical Vapor Deposition (CVD) method in different trench structures for the potential applications on the vertically three-dimension integrated circuits (3DICs). It’s unique material properties, including Resistivity (p), thermal conductivity (k), coefficient of thermal expansion (CTE), and Young’s modulus (E) make it viable for the potential applications in the monolithic 3D vertically integrated technologies. Besides the well-known lower p in CNTs for the easier electron carrier transport, the higher k-value in CNTs— which is ~4500 Wm-1K-1 and 10x higher than Cu— results in the better thermal dissipation (~I5°C reduction) for the reduction of self-heating effect in the high dense 3D devices. On the other hand, the near-zero/negative CTE of -2xlO-6 K-1 and ultra-high E-value of 1000 GPa in CNTs is also found to reduce the residual stress and furtherly enhance the acceptable device layout area (by 80% keep-out zone reduction) in the 3D vertically integrated devices significantly. The prototype and full process flow for the CNTs as the vertical connection material for the 3D integrated technologies is demonstrated successfully. In summary, the growth of high-quality CNTs in the trench structure with a good electrical and mechanical material properties, and the development of an advanced key- module process for the monolithic 3D vertically integrated technologies provide a useful solution for the future high- performance and high-dense 3D integrated devices.