Contact Behavior among Vertically Aligned Carbon Nanotube Bumps under Compression for Flexible Multilayer Substrates

Abstract

© The Author(s) 2016. Published by ECS.Vertically aligned carbon nanotubes (VACNTs) are promising candidates as vertical interconnects in multilayer substrates. Therefore, VACNTs were applied to the via structure in a multilayer flexible substrate as flexible bumps by surface activated bonding indeed. During the manufacturing process, VACNT bumps were compressed and deformed by the bonding pressure. In this research, VANCT deformation and structural mechanics were evaluated and analyzed under compression by an indenter. VACNT bumps were compressed to about 20% of their original height as multiple VACNT bundles folded under pressure more than 0.40 MPa. The VACNT compression height depended on the bonding pressure, which was within the range 0.04 to 0.20 MPa. Moreover, it was concluded that friction force between neighboring VACNTs caused plastic deformation of the VACNT bundles.