Low Temperature Curable Low Dk & Df Polyimide for Antenna in Package

Abstract In this paper, we developed novel low temperature curable (around 200~250 °C) Dk (2.7) & Df (0.002) polyimide with high glass transition (170 and elongation (100%). We also negative tone photosensitive (3.0) (0.007) by photo initiator cross linker. Material types of them are liquid or B-stage sheet materials. Patterning methods the non-photosensitive polyimides were imprint UV laser ablation. Resolution those process 10um via 30um respectively. Photosensitive was patterned photolithographic tool. fabricated fine photolithography. investigated frequency dependence up to 95 GHz, confirmed that gradually increased from 0.002 0.005 as increased. To confirm effect polyimide, insertion loss micro-strip line whose length 10 mm measured using new polyimide. Insertion (S21 parameter) 0.8 less than half conventional RDL structure tested bump shear strength after thermal cycle test. All mode ductile solder failure without delamination. Because our show excellent dielectric, mechanical properties, they suitable insulator for FO-AiP.