A comprehensive study of pyrazine-contained and low-temperature curable polyimide

One challenge in tailoring polyimide (PI) for microelectronics is to obtain excellent properties of films when cured at low temperature. To meet this challenge, this study put forwards an investigation of pyrazine moieties incorporated polyimide, which is comprehensively investigated on curing temperature dependence with thermal, mechanical, and dielectric properties. Self-catalytic effect stemming from pyrazine moiety has a significant improvement on imidization degree of PI films from 10.1% to 13.3% under 200 °C as revealed with ATR-FTIR spectrum. The resulting low temperature cured polyimide films with higher imidization degree exhibit excellent comprehensively properties. It is demonstrated that PI-1 shows high tensile strength (136 MPa), high Young's modulus (3.4 GPa) and low CTE value (4.7 ppm/°C) when cured at 200 °C. Besides, the temperature for 5% weight loss as high as 556 °C and glass transition temperature (Tg) as 367 °C of the PI film turn out to be superior thermal stability. Moreover, molecular dynamics simulation was carried out to get a theoretical perspective on the effect of intrinsic factors on a microscopic level associated with the molecular structure of the polyimides to gain a deeper view on the effect of imidizaiton degree on the Tg, chain mobility and conformational rigidity. This research gives a comprehensive study of pyrazine constructed polyimide for low-temperature cured polyimide and paves a way for its application in the microelectronics.