Paper
1 January 1988 Characterization Of Voting Suppression Of Optical Defects Through Simulation
Kenny K.H. Toh, Chong-Cheng Fu, Kevin L. Zollinger, Andrew R. Neureuther, R. Fabian W. Pease
Author Affiliations +
Abstract
Two-dimensional image simulation with SPLAT and resist profile dissolution simulation with SAMPLE are used to explore the suppression of large defects with voting in projection printing. The parameters chosen are for the Ultratech 1000 stepper due to the availability of experimental data with programmed defects. The results are stated in terms of feature and defect sizes in λ/NA where λ, is the wavelength and NA is the numerical aperture. Models based on 1) full resist dissolution simulation, 2) 30% clear field intensity of simulated images and 3) simple algebraic approximations are used. The case of using three votes on transparent defects placed at various locations in line patterns is studied in detail. An excellent fit between simulation and experimental results was obtained. It was also found that defect suppression with 3:1 voting is always a factor of 3 for small defects, and improves for larger defects except both when the partial coherence is less than 0.5 and when defects are within 0.2 λ/NA of a neighboring feature. Voting may be used to overcome mask defects which are so large that they have bridged patterns on the wafer. For 10% linewidth variation, the use of voting raises the critical defect size from 0.24 to 0.5 λ/NA. The effects of process bias and overlay are also explored.
© (1988) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Kenny K.H. Toh, Chong-Cheng Fu, Kevin L. Zollinger, Andrew R. Neureuther, and R. Fabian W. Pease "Characterization Of Voting Suppression Of Optical Defects Through Simulation", Proc. SPIE 0922, Optical/Laser Microlithography, (1 January 1988); https://doi.org/10.1117/12.968413
Lens.org Logo
CITATIONS
Cited by 4 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Semiconducting wafers

Optical lithography

Reticles

Laser optics

Photomasks

Feature extraction

Image analysis

Back to Top