High Throughput Grating Qualification for Rating Directed Self-Assembly Pattern Performance using Optical Metrology

Abstract

This paper describes a novel scatterometry-based optical inspection technique to quantify the degree of ordering of line/space gratings fabricated through a chemo-epitaxy directed self-assembly process. Process window analysis with this optical metrology is compared to analysis based on SEM and excellent agreement is demonstrated. However, other process parameters, including pattern CD, profile and especially pattern height influence the output signal. This requires normalization to a known good condition for correct data interpretation. The optical technique is useful for evaluating performance of closely related processes, and is thus ideally suited for bake optimizations, material selections, and monitoring purposes.