JP2015520377A5

JP2015520377A5 -

Info

Publication number: JP2015520377A5
Application number: JP2015514130A
Authority: JP
Filing date: 2013-05-21
Publication date: 2016-07-07
Anticipated expiration: 2033-05-21

Claims

An overlay target,
One or more segmented overlay pattern elements forming at least one overlay target structure;
One or more inactive pattern elements forming at least one dummy fill target structure, each of the one or more inactive pattern elements being at least one proximally disposed overlay pattern element An overlay target that includes a dummy fill segmented along an axis that is orthogonal to the segmentation axis.

The one or more inert pattern elements form at least one two-fold symmetric or four-turn symmetric overlay target structure, and the one or more overlay pattern elements are at least one two-fold symmetric or four times The overlay target of claim 1 forming a symmetric dummy fill target structure.

The one or more inert pattern elements include dummy fill segments disposed on one or more areas reserved for at least one subsequent process layer overlay pattern element. The listed overlay target.

The one or more inactive pattern elements are disposed in close proximity to an edge region of the one or more inactive pattern elements to enable location estimation of at least one pattern element. The overlay target of claim 1 comprising a segment.

The overlay target of claim 1, wherein each of the one or more inert pattern elements is two-fold symmetric.

The overlay target of claim 1, wherein the one or more overlay pattern elements are formed over the one or more inactive pattern elements.

The one or more inert pattern elements are selected at a selected pitch or substantially larger than a minimum design rule specified for an exposure tool configured to expose the one or more inert pattern elements The overlay target of claim 1, segmented according to feature size.

The one or more overlay pattern elements are formed on a subsequent process layer over the one or more inert pattern elements within a boundary defined by the one or more inert pattern elements. The overlay target according to claim 1.

The overlay target of claim 8, wherein a distance between the boundary and the one or more overlay pattern elements is longer than a predetermined light exclusion zone along an axis parallel to a dummy fill segmentation axis.

The overlay target of claim 8, wherein a distance between the boundary and the one or more overlay pattern elements is longer than a predetermined light exclusion zone along an axis perpendicular to a dummy fill segmentation axis.

The selected distance between the boundary and the one or more overlay pattern elements is a predetermined light exclusion zone along an axis parallel to the dummy fill segmentation axis and along an axis perpendicular to the dummy fill segmentation axis. The overlay target of claim 8, wherein the overlay target is longer.

The overlay target of claim 8, wherein the one or more inert pattern elements are printed by two or more side-by-side exposures.

The overlay target of claim 8, wherein the one or more overlay pattern elements include an aperture having an internal edge that enables location estimation of at least one pattern element.

The overlay target of claim 1, wherein the one or more inert pattern elements include spaced-apart dummy fill segments printed by separate exposures and aligned according to lithographic overlay tolerances.

The one or more inert pattern elements include regularly spaced dummy fill segments formed on subsequent process layers, the dummy fill segments printed by separate exposures and aligned according to lithographic overlay tolerances. The overlay target according to claim 1.

The overlay target of claim 1, wherein one or more of the pattern elements are segmented according to feature size.

The overlay target of claim 1, wherein the segmented dummy fill covers a majority of at least one layer disposed on the substrate.

The one or more overlay pattern elements and the one or more inactive pattern elements form at least a first target structure that is overlaid on a second target structure, each of the overlaid target structures The quadrant is
Two inert pattern elements formed from segmented dummy fills arranged to allow overlay measurements along a first axis orthogonal to the dummy fill segmentation axis;
The overlay target of claim 1, comprising two segmented overlay pattern elements subsequently disposed proximate to the at least two inactive pattern elements.

The overlay target of claim 18, wherein the first target structure and the second target structure are four-fold symmetric.

The overlay target of claim 18, wherein the two overlay pattern elements are arranged to allow overlay measurements along a second axis that is orthogonal to the first axis.

The overlay target of claim 18, wherein the two overlay pattern elements are arranged to allow overlay measurements along a second axis parallel to the first axis.

The one or more overlay pattern elements and the one or more inert pattern elements form at least a first four-fold symmetric target structure overlaid on a second four-turn symmetric target structure; Each quadrant of the overlaid target structure is
Inactive pattern elements formed from segmented dummy fills, each including an aperture having an internal edge that enables location estimation of at least one pattern element in at least one direction parallel to the dummy fill segmentation axis An inert pattern element that substantially fills each quadrant, except for the quadrant portion;
A segmented overlay pattern element subsequently disposed proximate to at least two inactive pattern elements, wherein the location estimation of at least one pattern element in the at least one direction parallel to the dummy fill segmentation axis The overlay target of claim 1, comprising: a segmented overlay pattern element that includes one or more edges to enable.

The one or more overlay pattern elements and the one or more inert pattern elements form at least a first two-fold symmetric target structure overlaid on a second two-turn symmetric target structure; Each quadrant of the overlaid target structure is
4 inactive pattern elements formed from segmented dummy fills, each of the 4 inactive pattern elements being arranged to allow overlay measurements along each axis Pattern elements,
Twelve segmented overlay pattern elements subsequently disposed proximate to the four inert pattern elements, each of the twelve overlay pattern elements so as to allow overlay measurements along each axis The overlay target of claim 1 comprising twelve segmented overlay pattern elements arranged.

A system for performing overlay measurements,
A sample stage configured to support a substrate, wherein the overlay target is disposed on the substrate, wherein the overlay target forms at least one overlay target structure. A segmented overlay pattern element, wherein the overlay target further includes one or more inactive pattern elements forming at least one dummy fill target structure, each of the one or more inactive pattern elements A sample stage including a dummy fill segmented along an axis orthogonal to the segmentation axis of at least one proximally disposed overlay pattern element;
At least one illumination source configured to illuminate the overlay target;
At least one detector configured to receive illumination reflected, scattered or emitted from the overlay target;
At least two layers communicatively coupled to the detector and disposed on the substrate using information related to the illumination reflected, scattered or emitted from the overlay target And at least one computing system configured to determine misalignment between.

The one or more inert pattern elements form at least one two-fold symmetric or four-turn symmetric overlay target structure, and the one or more overlay pattern elements are at least one two-fold symmetric or four times 25. The system of claim 24, forming a symmetrical dummy fill target structure.

25. The one or more inert pattern elements include dummy fill segments disposed on one or more regions reserved for at least one subsequent process layer overlay pattern element. The described system.

The one or more inactive pattern elements are disposed in close proximity to an edge region of the one or more inactive pattern elements to enable location estimation of at least one pattern element. The system of claim 24, comprising a segment.

25. The system of claim 24, wherein the computing system is further configured to determine a location of at least one pattern element based on information collected in a direction perpendicular or parallel to the dummy fill segment.

The computing system is further configured to determine a location of at least one pattern element based on information collected in a direction perpendicular to the dummy fill segment and information collected in a direction parallel to the dummy fill segment. 25. The system of claim 24.

The computing system is further configured to determine a location of at least one inactive pattern element based on information collected in a first direction, and based on information collected in a second direction 25. The system of claim 24, further configured to determine a location of at least one overlay pattern element.

The computing system includes an edge of at least one pattern element disposed in a first direction parallel to a measurement axis and an edge of the at least one pattern element disposed in a second direction perpendicular to the measurement axis. 25. The system of claim 24, further configured to determine a measurement bias based on a direction of segmentation based on.

The system of claim 24, wherein the computing system is configured to measure overlay alignment in a first direction.

The computing system is further configured to measure overlay alignment in a second direction, the first direction being associated with a first overlay target structure disposed on the substrate, and the second direction. 35. The system of claim 32, wherein the orientation is associated with a second overlay target structure that is subsequently disposed on the substrate.

The computing system is further configured to measure overlay alignment in a second direction, wherein the first direction is associated with an overlay target structure disposed on the substrate over a dummy fill target structure. The system of claim 32, wherein the second direction is associated with the dummy fill target structure.

A method for performing overlay measurement, comprising:
Illuminating an overlay target disposed on a substrate, wherein the overlay target includes one or more segmented overlay pattern elements forming at least one overlay target structure, the overlay target comprising: , Further comprising one or more inert pattern elements forming at least one dummy fill target structure, each of said one or more inert pattern elements being disposed at least one proximally Illuminating, including a dummy fill segmented along an axis orthogonal to the segmentation axis of the element;
Detecting illumination reflected, scattered or emitted from the overlay target; and
Utilizing information related to the detected illumination to determine misalignment between at least two layers disposed on the substrate.

The one or more inert pattern elements form at least one two-fold symmetric or four-turn symmetric overlay target structure, and the one or more overlay pattern elements are at least one two-fold symmetric or four times 36. The method of claim 35, wherein a symmetric dummy fill target structure is formed.

36. The one or more inert pattern elements include dummy fill segments disposed on one or more regions reserved for at least one subsequent process layer overlay pattern element. The method described.

The one or more inactive pattern elements are disposed in close proximity to an edge region of the one or more inactive pattern elements to enable location estimation of at least one pattern element. 36. The method of claim 35, comprising a segment.

36. The method of claim 35, further comprising determining a location of at least one pattern element based on information associated with illumination detected in a vertical or parallel direction of the dummy fill segment.

Determining a location of at least one pattern element based on information related to illumination detected in a direction perpendicular to the dummy fill segment and information related to illumination detected in a direction parallel to the dummy fill segment. 36. The method of claim 35, further comprising:

Determining the location of at least one inert pattern element based on information associated with illumination detected along the first measurement axis; and
36. The method of claim 35, further comprising determining a location of at least one overlay pattern element based on information related to illumination detected along the second measurement axis.

Depending on the direction of segmentation based on the edge of at least one pattern element arranged in a first direction parallel to the measurement axis and the edge of the at least one pattern element arranged in a second direction perpendicular to the measurement axis 36. The method of claim 35, further configured to determine a measurement bias.

36. The method of claim 35, further comprising measuring overlay alignment in the first direction.

Measuring an overlay alignment in a second direction, wherein the first direction is associated with a first overlay target structure disposed on the substrate, and the second direction is on the substrate. 44. The method of claim 43, associated with a second overlay target structure subsequently disposed on the substrate.

Measuring an overlay alignment in a second direction, wherein the first direction is related to an overlay target structure disposed on the substrate over a dummy fill target structure, and the second direction is 44. The method of claim 43, associated with the dummy fill target structure.

A diffraction-based overlay target,
A first overlay target structure printed on a substrate and including a first plurality of segmented pattern elements;
Printed on the substrate and includes a second plurality of segmented pattern elements, wherein a portion of the second plurality of segmented pattern elements overlies a portion of the first plurality of segmented pattern elements. A second overlay target structure, arranged to wrap;
And the arrangement of the first overlay target structure and the second overlay target structure is four-fold symmetric, and is at least part of the first plurality of segmented pattern elements or at least the second segmented pattern element. A part of the pattern element is formed on the substrate by two or more side-by-side exposures.
A diffraction-based overlay target .