Translator Disclaimer
12 June 2003 Improving chemically amplified resist modeling for 2D layout patterns
Author Affiliations +
Physical insight into acid movement in Fickean and non-Fickean diffusions is illustrated for chemically-amplified (CA) resist system. According to this new insight, we propose two diffusion-sensitive patterns for the detection of acid diffusion, which are a sequentially double exposed cross pattern and standing waves from an isolated trench. Their shapes on the wafer are highly dependent on the type of acid diffusion in photoresist. By comparing the simulated shapes of these two patterns with experimental SEM measurements, a method of characterizing PEB modeling is developed. This new method can distinguish Fickean and non-Fickean diffusion and extract post-exposure (PEB) parameters accurately. This method is applied to APEX-E and UV210 and shows that reduced non-Fickean diffusion models both of these resists the best. The development thresholds for both 1D and 2D patterns under various image slopes are systematically investigated for APEX-E and UV210. A programmed foreground and background double exposure is applied to vary the image slope. This study demonstrates that thresholds for 2D trench end patterns are higher than that for 1D trenches. Except for the threshold for 1D trenches in UV210, which remains a constant regardless of image slope, all thresholds increase as image slope decreases. Thresholds in APEX-E increase up to 60% as image slope decreases by 30% while thresholds for trench end patterns in UV210 increase up to 20% as the slope decreases by 25%.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lei Yuan and Andrew R. Neureuther "Improving chemically amplified resist modeling for 2D layout patterns", Proc. SPIE 5039, Advances in Resist Technology and Processing XX, (12 June 2003);

Back to Top