Sustainable Dielectric Films with Ultralow Permittivity from Soluble Fluorinated Polyimide
Hejian Li,
Xiangyi Kong,
Shixiao Wang,
Min Gong,
Xiang Lin,
Liang Zhang,
Dongrui Wang
Affiliations
Hejian Li
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Xiangyi Kong
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Shixiao Wang
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Min Gong
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Xiang Lin
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Liang Zhang
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
Dongrui Wang
Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
In the rapidly growing area of high-frequency communications, polyimide films with ultralow dielectric constant and dielectric loss, adequate insulating strength, and recyclability are in high demand. Using a synthesized soluble fluorinated polyimide, a series of recyclable porous dielectric films with varying porosities were fabricated in this study through nonsolvent-induced phase separation. By manipulating the mass ratio of the binary solvent used to dissolve the polyimide, the shape, size, and size distribution of the pores generated throughout the polyimide matrix can be accurately regulated. The porosity and average pore size of the as-prepared porous films were adjustable between 71% and 33% and between 9.31 and 1.00 μm, respectively, which resulted in a variable dielectric constant of 1.51–2.42 (100 kHz) and electrical breakdown strength of 30.3–119.7 kV/mm. The porous sPI film with a porosity rate of 48% displayed a low dielectric constant of 2.48 at 10 GHz. Coupled with their superior thermal stability, mechanical characteristics, and recyclability, these porous polyimide films are highly promising for constructing high-frequency microelectronic devices.
