Abstract: Methods for optimizing an aspect of a patterning process based on defects. For example, a method of source and mask optimization of a patterning process includes obtaining a location on a substrate having a threshold probability of having a defect; defining an defect ambit around the location to include a portion of a pattern on the substrate and one or more evaluation points associated with the portion of the pattern; determining a value of a first cost function based on a defect metric associated with the defect; determining a first guide function for the first cost function, wherein the first guide function is associated with a performance metric of the patterning process at the one or more evaluation locations within the defect ambit; and adjusting a source and/or a mask characteristic based on the value of the first cost function, and the first guide function.

Abstract: A control device configured to determine a primary first drive signal, based on a first error signal representing a difference between desired and measured positions of a first body, for driving a positioner driving the first body; determine a primary second drive signal, based on a second error signal representing a difference between desired and measured positions of a second body, for driving a positioner driving the second body; determine, based on the second error signal, a secondary first drive signal for driving the first body positioner; determine, based on the first error signal, a secondary second drive signal for driving the second body positioner; combine the primary and secondary first drive signals and combine the primary and secondary second drive signals; and output the combined first and second drive signals to the respective positioning devices.

Abstract: An imprint lithography apparatus is disclosed that has a first array of template holders, a second array of template holders, and a substrate table arranged to support a substrate to be imprinted, wherein the first array of template holders is arranged to hold an array of imprint templates that can be used to imprint a first array of patterns onto the substrate, and the second array of template holders is arranged hold an array of imprint templates that can be used to imprint a second array of patterns onto the substrate, the patterns imprinted by the second array being interspersed between the patterns imprinted by the first array.