Paper-mediated controlled densification and low temperature transfer of carbon nanotube forests for electronic interconnect application

We report on the fabrication and characterization of densified and transferred carbon nanotube forests for electronic interconnect application. A simple, low cost and quality method is developed for densifying vertically-aligned carbon nanotube (VA-CNTs) forests at room temperature. Commercially available paper is utilized in this work to serve as a solvent carrier. Highly densified CNT bundles are formed by the sorption of evaporative liquid from the paper into carbon nanotube forests. An average Young’s modulus increase from approximately 15.8 to 111.9 MPa is extrapolated from the measured load–displacement curves in the compression tests of the as-densified VA-CNTs. Subsequent low temperature transfer method is used to transfer the VA-CNT bundles onto the target substrate. Four-probe measurement of the transferred VA-CNTs shows resistance of 3.70 ± 0.04 Ω of each CNT bundle.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A new method for densifying carbon nanotubes forests using solvent wetted paper. ► Minimum processing steps which produce high quality densification results. ► Controlled fabrication of both fully and partially densified VA-CNTs. ► Compression test and resistance measurement are performed on densified CNTs.