Chemical-Vapor-Deposition (CVD) Growth of Porous Two-Dimensional Polymer for Dielectric Applications in Microelectronics

Two dimensional polymers (2DPs) with designable structure and exciting physical and chemical properties, are increasing their interest for next generation technologies. In microelectronics area, the porous structures of 2DPs will lead to extra low dielectric constant (k<2), which can significantly decrease the interconnect crosstalk and reduce the resistance-capacitance (RC) delay. Distinct from other low-k dielectric, with process low thermal conductivity and low mechanical properties, benefit from the in-plane rigid covalent bonds and out of plane π-π stacking, 2DPs exhibit excellent mechanical and thermal properties, makes them promising low-k dielectric materials for next generation microelectronics. Here, we used CVD method to prepare a fluoride-rich 2DP (2DP-F) and measured its dielectric and mechanical properties. The CVD grown 2DP-F can confocally deposit on arbitrary substrates at low temperature and exhibited extra low-dielectric constant (~1.8) along with excellent Young’s modulus (~18 GPa). We further integrated 2DP-F as dielectric interlayer in MoS2 field effect transistors. The inert surface of 2DP-F reduces the interfacial scattering between MoS2 and oxides, significantly increase the FET performance significantly. We also prepared hybrid 2DP-oxide structure based on vapor metal catalysts at low temperature (<200 C). These hybrid structures demonstrated a tunable dielectric constant across a broad range. Our results highlight the potential applications of 2DPs as both high-performance low-k and high-k dielectric materials for next-generation microelectronics.