Assembly Process and Electrical Properties of Top-Transferred Graphene on Carbon Nanotubes for Carbon-Based 3-D Interconnects

Carbon nanomaterials, graphene, and carbon nanotubes (CNTs) have emerged as promising materials for the integration of future advance packaging technologies. The main benefits of carbon nanomaterials include excellent electrical, thermal, and mechanical properties. In this article, the transfer process of a top graphene layer onto the as-grown CNT bundles was successfully performed with direct graphene-to-CNT contact at the interface. Four-point-probe (4PP) I-V characterization suggests that an ohmic contact was achieved between the graphene and CNTs. Low CNT bump resistance of 2.1 Ω for 90 000-μm
²
CNT area including the CNT-graphene contact resistance was obtained, demonstrating a reduction in the contact resistance between the CNT and Au under the same fabrication and measurement conditions. This work presents the preliminary results for the assembly process of top-transferred graphene on the CNTs and the electrical properties of direct CNT-graphene contact, paving the way for the implementation of full-carbon-based three-dimensional (3-D) interconnects.