Cool-curing polymer simplifies IC fabrication

Rensselaer Polytechnic Institute and Polyset have developed an inexpensive, quick-drying polymer that promises to cut costs for current IC-packaging processes by simplifying the construction of redistribution layers. Meanwhile, the material also shows promise in ultraviolet on-chip nanoimprinting lithography, a potential next-generation IC-patterning technology.

The material, PES (polyset-epoxy siloxane), cures at 165°C, about 35% cooler than the benzocyclobutene and polyimide that chip-packaging companies now rely on for redistribution layers. That reduced need for heat translates directly to savings in overhead costs, according to the researchers.

The material matches the other materials in key characteristics, such as thermal stability, low thermal expansion, low dielectric constant, and low leakage current, but surpasses them in water-uptake rate and the ability to adhere to copper.

Rensselaer Polytechnic Institute, www.rpi.edu
Polyset, www.polyset.com


Caption

A series of electron-microscope images of a new polymer at 30 microns (a), 10 microns (b), 3 microns (c), and 1 micron (d) show its ability to create well-defined patterns in a UV-imprint-lithography application.