Closing the stochastic resolution gap

BackgroundSince the birth of the integrated circuit, electronics industry growth and innovation have relied on semiconductor manufacturers putting ever smaller features (described by their critical dimensions or CDs) into production. Yet today, stochastics, the randomness inherent to chip making near the atomic scale, is threatening the continued ability to manufacture the smallest possible features in volume production.AimTo understand the impact of stochastics on semiconductor manufacturing today, the stochastic resolution gap is defined and used as a framework assessing the value of reducing stochastic variability.ApproachWe provide an introduction to stochastics, their emerging limitations on lithography resolution, technology solutions for improving resolution and yield, and the importance of accurate measurement technology for bridging the stochastic resolution gap.ResultsUsing one stochastics-aware design rule example, a method for determining the optimum via size in a specific 28-nm pitch process is presented to minimize the detrimental role of stochastics.ConclusionsThe stochastic resolution gap is a real limitation, but it is not fixed. Further efforts are needed to continue to close this gap.