In-situ polymerization of low-dielectric fluorinated nano carbon/polyimide composites with low-temperature curable property

Abstract One challenge in advanced dielectric material of polyimides (PIs) is to obtain the excellent mechanical, thermal, and dielectric properties at low imidization temperature for fan-out wafer level package in 5G high-frequency communication. In this work, 6-aminoquinoline (AQL) is introduced through covalent bonds to obtain a low-temperature curable PI at first. The results demonstrate that with few addition (2.76%) of AQL, the imidization index could reach as high as 1.01 at 200 oC. Then, fluorinated nano carbon (FC) is further introduced by in situ polymerization resulting in the fluorinated nano carbon/polyimide (FCPI) composites, which effectively reduces the dielectric constant (1wt%, 2.75 @ 1MHz). Besides, the as-prepared FCPIs also possess excellent thermal property, especially when the addition amount is 0.3wt%, the 5% weight loss temperature could be as high as 540 oC and the glass transition temperature is 385 oC. Furthermore, the tensile strength of the film is 127 MPa, the elongation at break is around 15.82%, and the Youngs’ modulus is about 3.10 GPa. So, the successful preparation of the FCPI nanocomposites not only possess low-temperature curing and low-dielectric performance but also exhibit excellent thermal and mechanical properties, which shows a wide range of application prospects in the field of microelectronics for the advanced electronic package.