Lithographic apparatus and device manufacturing method
AssigneeASML Netherlands B.V.
InventorsAlexander Viktorovych Padiy, Boris Menchtchikov, Scott Anderson Middlebrooks
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Abstract
A method controls scanning function of a lithographic apparatus. A monitor wafer is exposed to determine baseline control parameters pertaining to the scanning function. The baseline control parameters are retrieved from the monitor wafer. Parameter drift is determined from the baseline control parameters. Compensation is performed based on the determination. A different parameterization is used for control of the scanning control module than for communication between the scanning control module and the lithographic apparatus.
Claims27
A lithographic apparatus comprising:
- a support configured to support a patterning device;
- a substrate table configured to hold a substrate;
- a patterning system configured to transfer a pattern from the patterning device onto a target portion of the substrate;
- a control module configured to control at least one of the support, substrate table or patterning system by periodically retrieving measurements defining baseline control parameters from one or more reference substrates so as to determine parameter drift from the baseline control parameters, thereby enabling allowance and/or correction to be made for the drift, the reference substrates having initially undergone patterning so as to determine the baseline control parameters;
- and
- an interface between the control module and the lithographic apparatus;
- wherein a parameterization of the interface is generic and different from a control parameterization used for control of at least one of the support, substrate table or patterning system, and
- wherein the parameterization of the interface is projected onto the control parameterization before the correction is made.
A method of using a control module to control scanning/stepping function of a lithographic apparatus comprising:
- exposing a reference substrate to determine baseline control parameters pertaining to the scanning/stepping function;
- periodically retrieving the baseline control parameters from the reference substrate;
- determining parameter drift from the baseline control parameters;
- and
- compensating based on the determination,
- wherein the method is performed using a parameterization for control different than a generic parameterization for communication between the control module and the lithographic apparatus, and
- wherein the parameterization for the communication is projected onto the parameterization for the control before the compensating is made.
Dependencies are inferred from the claim text.