Method for exposing a substrate and lithographic projection apparatus
AssigneeASML Netherlands B.V.
InventorsJozef Maria Finders, Judocus Marie Dominicus Stoeldraijer, Johannes Wilhelmus De Klerk
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Abstract
A method for exposing a resist layer on a substrate to an image of a pattern on a mask is disclosed whereby, after starting exposure and before completing exposure, a controlled amount of contrast loss is introduced by a controller in the image at the resist layer by changing during exposure the position of the substrate holder. The contrast loss affects the pitch dependency of the resolution of a lithographic projection apparatus, and its control is used to match pitch dependency of resolution between different lithographic projection apparatus.
Claims20
A method of operating a lithographic projection apparatus comprising:
- projecting a patterned beam onto a target portion of a substrate;
- storing data representing a target iso-dense bias characteristic and an iso-dense bias characteristic representative for a process run on the lithographic projection apparatus;
- determining, based on said data, one or more apparatus parameter-setting changes;
- and
- applying said one or more apparatus parameter-setting changes, wherein said one or more apparatus parameter-setting changes comprise:
- (a) a change of position of a substrate table supporting the substrate with respect to a notional image surface of a projection system of the lithographic projection apparatus along a Z-direction substantially perpendicular to said notional image surface;
- and/or
- (b) a change of rotational orientation of the substrate table around an axis substantially parallel to said notional image surface and substantially perpendicular to a scanning direction.
A lithographic projection apparatus comprising:
- a support structure configured to support a patterning device, the patterning device serving to impart a beam of radiation with a pattern in its cross-section;
- a substrate table configured to hold a substrate;
- a projection system having a notional image surface, configured to project the patterned beam onto a target portion of the substrate;
- a memory device configured to store data representing a target iso-dense bias characteristic and an iso-dense bias characteristic representative for a process run on the lithographic projection apparatus;
- and
- a controller constructed and arranged to determine, based on said data, one or more apparatus parameter-setting changes and to apply said one or more apparatus parameter-setting changes, said one or more apparatus parameter-setting changes comprising:
- (a) a change of position of the substrate table with respect to said notional image surface along a Z-direction substantially perpendicular to said notional image surface;
- and/or
- (b) a change of rotational orientation of the substrate table around an axis substantially parallel to said notional image surface and substantially perpendicular to a scanning direction.
Dependencies are inferred from the claim text.