Advanced COPNA-resin as a low temperature curing resin for high-density electronic packages

A novel type of low temperature curing resin for both LSI packages and high-density electronic packages was synthesized. The resin, named advanced COPNA-resin, was synthesized from naphthalene and 1,4-benzenedimethanol under an acid catalyst. The resin could be cured at lower temperature than generally used polyimide resin by more than 100°C. Beside the property of low temperature curing, the new resin exhibited attractive properties as an electronic insulating material of LSI packages and high-density packages: high glass transition temperature (250°C), low dielectric constant (ε_r3.1 for 1 MHz frequency), and small water absorption (0.37 wt.%). The resin could form thin films at the film thickness range from 5 to 20 μm when the spin speed range was from 1000 to 5000 rpm. The obtained thin films exhibited sufficient planarity in practical uses, and a precisely patterning property by a plasma etching method. In this paper, we also carried out the analysis for reaction process of the B-staged advanced COPNA-resin by using infrared absorption spectroscopy and ¹³C-NMR spectroscopy