Low-k fluorinated amorphous carbon interlayer technology for quarter micron devices

Abstract

We have developed a new interlayer technology that attains a 50% reduction in capacitance and keeps good process compatibility with current Chemical Mechanical Polishing (CMP) based multi-level metallization (MLM) processes. This technology uses fluorinated amorphous carbon (a-C:F) with a dielectric constant of 2.3, sandwiched between layers of SiO/sub 2/, which are formed sequentially by high density plasma-chemical vapor deposition (HDP-CVD). The top SiO/sub 2/ layer assures oxygen plasma resistance during via etching, metal etching, and resist removal.