Carbon nanotube synthesis for integrated circuit interconnects

[摘要] (cont.) Growth of dense carpets of vertically-aligned CNTs on conductive substrates below 5000C: By focusing on the material properties of the catalyst and underlayer, we discovered important requirements for the underlayer grain structure evolution, as well as by preheating the incoming hydrocarbon gas, growth of dense and vertically aligned carpets of nanotubes on conductive underlayers at growth temperatures below 5000C could be achieved. Electrical characterization showed that we obtained ohmic contact between the CNTs and the substrate. Control of CNT crystallinity via gas preheating : We discovered that the time and temperature of gas preheating was critical for the crystallinity of the resulting CNTs. This was done by comparing the output gases from varying gas preheat treatments to the corresponding CNT structures. This allowed a discussion of the critical gas compounds responsible for growth of crystalline CNTs. Growth of CNTs into periodic insulating scaffolds on conductive substrates: We have grown CNTs on conductive substrates and in regularly-spaced pores of an insulating anodized alumina scaffold. This allowed simulation of an interconnect via system for future measurement of the electrical properties of CNTs. This structure can also serve as a starting point for future development of dense arrays of CNT-based devices.

[发布机构] Massachusetts Institute of Technology