Low temperature grown carbon nanotube interconnects using inner shells by chemical mechanical polishing

Vertically aligned multiwalled carbon nanotubes (MWCNTs) were synthesized by remote plasma chemical vapor deposition at a low temperature of 390 °C, which meets the requirement of the large scale integration (LSI) process. For wiring application, we measured the electrical properties of MWCNT-via structures with and without chemical mechanical polishing (CMP). The via resistances were reduced using inner shells of MWCNTs whose caps were opened due to CMP. The improved resistance after annealing at 400 °C was 0.6 for 2 μm vias. Our process is suitable for LSI because the temperature never exceeds the allowable temperature of 400 °C in the Si LSI process.