Polymer Foundation
High performance fluorinated polymer films provide low dielectric loss and high thermal stability for flexible printed circuit substrates. Fluorinated polyimide incorporates fluorine atoms into the backbone chain of aromatic polyimide, reducing dielectric constant and moisture absorption compared to standard polyimides. The material governs signal speed and impedance stability in high frequency flexible interconnects and rigid-flex board constructions.
It reaches its application boundary in rigid multilayer boards where lower cost FR-4 or modified epoxy systems satisfy power and signal requirements.
Thermal Stability
Fluorine substitution within the polymer chain suppresses moisture uptake without degrading glass transition temperature or mechanical strength. Flexible circuits manufactured with this material withstand standard lead-free soldering profiles while maintaining low outgassing characteristics in high vacuum environments.
Dielectric Performance
Standard polyimide materials exhibit dielectric constants around three point five and moisture absorption rates near three percent, which degrade high frequency signals through dielectric absorption and impedance drift. Incorporating trifluoromethyl groups into the molecular structure lowers the dielectric constant below three point zero and cuts moisture absorption in half. This chemical modification minimizes propagation delays and phase distortion across high speed flexible cables.
Board fabricators utilize specialized surface treatment steps to ensure copper foil adhesion remains strong on the non-wetting fluorinated polymer substrate.
