Optimization of Selective Inhibition for Void-Suppressed Tungsten Gap-Fill

The scaling of logic and memory process technology has brought about challenges in tungsten gap-fill for metallization. In high aspect ratio and re-entrant structures, suppression of void in gap-fill tungsten metal is crucial for yield and device performance. This paper presents the enhanced tungsten gap-fill by inserting selective inhibition between deposition steps. The gap-fill performance can be optimized by tuning the intensity and gradient of inhibition process.