Low Temperature Curing Copolyimide with Monomer Containing Pyrazine Moiety

Polyimides (PIs) are a specific kind of polymer that extensively applied in microelectronics for their outstanding thermal stability, thermo-mechanical property and electrical property. Imidization of traditional PIs were commonly completed at about
$\mathbf{350^{\circ}}\mathbf{C}$
, which limits their applicable scope in the process of semiconductor manufacturing. Therefore, it is highly required to achieve superior properties of films when annealed below
$\mathbf{250^{\circ}}\mathbf{C}$
. This study comprehensively investigated thermal and mechanical properties of pyrazine moieties incorporated copolyimide. The thermo-mechanical properties of copolyimide based on
$4,4^{\prime}$
-(pyrazine-2,5-diyl)dianiline monomer exhibit excellent mechanical properties and low coefficient of thermal expansion when cured at
$\mathbf{200^{\circ}}\mathbf{C}$
(tensile strength of 138 MPa, modulus of 3.1 GPa and CTE of
$9.31\ \mathbf{ppm}/^{\circ}\mathbf{C})$
and
$\mathbf{250{}^{\circ}}\mathbf{C}$
(tensile strength of 191 MPa, modulus of 3.6 GPa and CTE of
$9.32 \mathbf{ppm}/^{\circ}\mathbf{C}$
). The aggregation structure as well as molecular orientation was investigated by W AXRD and polarized FTIR spectrum. This research gives an investigation of pyrazine-containing copolyimide for low-temperature curable polyimide and provides opportunities of application in the microelectronics.