Mixed Exposure Strategies

Motivation:

Preparing an optimized exposure strategy is straightforward with patterns with simpler characteristics. However, exposing patterns with complex or mixed characteristics can be challenging and may require breaking up into multiple exposures. To make the exposure job creation easier, less error-prone, and save time, it can be preferred to process the entire pattern in one exposure file.

Solution:

Take advantage of multiple options for field control within a single exposure file, optimum results for complex layouts can be achieved. In this document we show examples for mixed exposure strategies for layout incorporating both horizontal and vertical gratings spanning multiple deflection fields, another example of mixing floating and overlapping fields, and applications such as a closure test. This technique can be accomplished with two methods: (1) using multiple export modules and merging those results, and (2) using the full feature set of the Fields module to order the data. There is no limit to the number of exports that can be combined into one exposure file. This approach is very useful to improve lithography results by choosing the best strategies and saves time by only exposing one file.