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  • High- κ polymers of intrinsic microporosity: a new class of high temperature and low loss dielectrics for printed electronics
Title: High- κ polymers of intrinsic microporosity: a new class of high temperature and low loss dielectrics for printed electronics
High performance polymer dielectrics are a key component for printed electronics. In this work, organo-soluble polymers of intrinsic microporosity (PIMs) are reported for the first time to demonstrate desirable dielectric properties with a high permittivity (or κ ), heat resistance, and low dielectric loss simultaneously. Due to the highly dipolar sulfonyl side groups (4.5 D) and rigid contorted polymer backbone, a sulfonylated PIM (SO 2 -PIM) enabled friction-free rotation of sulfonyl dipoles in the nanopores. As such, an optimal balance between relatively high κ and low dielectric loss is achieved in a broad temperature window (−50–200 °C). For example, the discharged energy density reached 17 J cm −3 with κ = 6.0. The discharge efficiency was 94% at 150 °C/300 MV m −1 and 88% at 200 °C/200 MV m −1 . Furthermore, its application as a high- κ gate dielectric in field effect transistors (FETs) is demonstrated. With the bilayer SO 2 -PIM/SiO 2 gate dielectric, InSe FETs exhibited a high electron mobility in the range of 200–400 cm 2 V −1 s −1 , as compared to 40 cm 2 V −1 s −1 for the bare SiO 2 -gated InSe FET. This study indicates that highly dipolar PIMs with a rigid polymer backbone and large free volume are promising as next generation gate dielectric materials for printed electronics.  more » « less
Award ID(s):
1708990
PAR ID:
10148935
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Materials Horizons
Volume:
7
Issue:
2
ISSN:
2051-6347
Page Range / eLocation ID:
592 to 597
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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