Integration of horizontal carbon nanotube devices on silicon substrate using liquid evaporation

This paper presents a process to fabricate horizontal carbon nanotube (CNT) components with controllable orientations and positions on silicon substrate. This process makes use of capillary effect to pull down inclined CNT bundles. Liquid wettable to both CNT bundles and silicon substrates was used to generate attractive force to level the CNT. The final orientation of CNT bundles was determined by the initial inclination of the CNT grown. The geometric patterns of catalyst film have significant effect on the initial inclination. Using the electron-shading effect, specially designed catalyst patterns and the liquid evaporation process, we demonstrated good control on the positions, the dimensions, and the orientations of on-chip grown CNT, thus facilitating the on-chip integration of CNT components.