High κ polymers of intrinsic microporosity: A new class of high-temperature and low-loss dielectrics for microelectronic applications

High performance polymer dielectrics is a key component for power and printable electronics. In this work, organo-soluble polymers of intrinsic microporosity (PIMs) are reported for the first time to show desirable dielectric properties with high permittivity (or κ), high temperature capability, and low dielectric loss. Due to the polar sulfonyl side groups and rigid contorted polymer backbone, sulfonylated PIM (SO₂-PIM) exhibited an optimized balance between relatively high κ and low dielectric loss in a broad temperature window (up to 200 °C). For examples, its discharged energy density reached as high as 17 J cm^-3 with κ = 6.0. The discharge efficiencies were 94% at 150 °C/300 MV m^-1 and 88% at 200 °C/200 MV m^-1. Furthermore, its application as high-κ gate dielectrics in field effect transistors (FETs) is demonstrated. With the bilayer SO₂-PIM/SiO₂ gate dielectric, the InSe FETs exhibited a significantly improved electron mobility in the range of 200-400 cm² V^-1 s^-1, much higher than 40 cm² V^-1 s^-1 for the bare SiO₂-gated InSe FET. This study indicates that highly dipolar PIMs with rigid polymer backbone and large free volume are promising as high performance, next generation polymer dielectrics.