Test structure design for metrology measurements in patterned samples
OwnerGilad Barak, Oded Cohen +1inventors
InventorsGilad Barak, Oded Cohen, Igor Turovets
Life of this patent
Estimating the term…
Abstract
A test structure for use in metrology measurements of a sample pattern formed by periodicity of unit cells, each formed of pattern features arranged in a spaced-apart relationship along a pattern axis, the test structure comprising a test pattern, which is formed by a main pattern which includes main pattern features of one or more of the unit cells and has a symmetry plane, and a predetermined auxiliary pattern including at least two spaced apart auxiliary features located within at least some of those features of the main pattern, parameters of which are to be controlled during metrology measurements.
Claims8
A test structure for use in metrology measurements of a sample pattern formed by periodicity of unit cells, each formed of pattern features arranged in a spaced-apart relationship along a pattern axis, the test structure comprising a test pattern, which is formed by a main pattern which includes main pattern features of one or more of the unit cells and has a symmetry plane, and a predetermined auxiliary pattern including at least two spaced apart auxiliary features located within at least some of those features of the main pattern, wherein parameters of the main pattern features are to be controlled during metrology measurements, wherein the auxiliary features of the auxiliary pattern are configured and arranged with respect to the main pattern such that data indicative of optical response from the test structure satisfies a condition of symmetry around a measurement plane being parallel to the symmetry plane of the main pattern, if and when at least one parameter of the main pattern being controlled is maintained within the test structure, and does not satisfy said condition of symmetry around said measurement plane if and when said at least one parameter varies within the test structure.
A test structure for use in metrology measurements of a sample pattern formed by periodicity of unit cells, each formed of pattern features arranged in a spaced-apart relationship along a pattern axis, the test structure comprising a test pattern, which is formed by a main pattern which includes main pattern features of one or more of the unit cells and has a symmetry plane, and a predetermined auxiliary pattern including at least two spaced apart auxiliary features located within at least some of those features of the main pattern, wherein parameters of the main pattern features are to be controlled during metrology measurements, wherein the test pattern comprises the main pattern comprising at least one unit cell, the unit cell comprising three lines with two respective spacings between them, and the auxiliary pattern associated with the at least one unit cell and comprising two vias located in and extending across said two spacings, respectively, thereby enabling control of widths of the spacings by optical measurements using a measurement plane parallel to the symmetry plane of the main pattern which is parallel to the pattern axis.
A test structure for use in metrology measurements of a sample pattern formed by periodicity of unit cells, each formed of pattern features arranged in a spaced-apart relationship along a pattern axis, the test structure comprising a test pattern, which is formed by a main pattern which includes main pattern features of one or more of the unit cells and has a symmetry plane, and a predetermined auxiliary pattern including at least two spaced apart auxiliary features located within at least some of those features of the main pattern, wherein parameters of the main pattern features are to be controlled during metrology measurements, wherein the test pattern comprises the main pattern comprising at least one pair of locally adjacent unit cell, the unit cell comprising two spaced lines, and the auxiliary pattern associated with one unit cell of the pair and comprising two vias located in and extending across said two spacings, respectively, thereby enabling control of widths of the spacings, by optical measurements using a measurement plane parallel to the symmetry plane of the main pattern which is perpendicular to the pattern axis.
Dependencies are inferred from the claim text.