Definition
The pattern density effect is process variation caused by differences in the local density of patterned features; in CMP, different pattern densities can polish at different rates.
Application
Accounted for in CMP layout and process optimization to reduce nonuniform removal, dishing, erosion, and uneven clearing across regions of different feature density.
Related concepts
Evidence and further reading
- Evidence from cnfusers.cornell.eduhttps://www.cnfusers.cornell.edu/sites/default/files/Equipment-Resources/CMP%20Primer.pdf
- Evidence from boning.mit.eduhttps://boning.mit.edu/wp-content/uploads/2022/11/MIT-IntCMPSymp-Dec2000-ver4db.pdf