Sensitivity study of two high-throughput resolution metrics for photoresists.
The resolution of chemically amplified resists is becoming an increasing concern, especially for lithography in the extreme ultraviolet (EUV) regime. Large-scale screening is currently under way to identify resist platforms that can support the demanding specifications required for EUV lithography. Current screening processes would benefit from the development of metrics that can objectively quantify resist resolution in a high-throughput fashion. Here we examine two high-throughput metrics for resist resolution determination. After summarizing their details and justifying their utility, we characterize the sensitivity of both metrics to known uncertainties in exposure tool aberrations and focus control. For an implementation at EUV wavelengths, we report aberration and focus-limited error bars in extracted resolution of approximately 1.25 nm rms for both metrics, making them attractive candidates for future screening and downselection efforts.