A method of position control of an optical component relative to a surface is disclosed. The method may include: obtaining a first signal by a first position measurement process; controlling relative movement between the optical component and the surface for a first range of motion using the first signal; obtaining a second signal by a second position measurement process different than the first position measurement process; and controlling relative movement between the optical component and the surface for a second range of motion using the second signal, the second range of motion being nearer the surface than the first range of motion.

A method of calculating electromagnetic scattering properties of a structure, the structure including materials of differing properties and the structure being periodic in at least one lateral direction and extending in a vertical direction, comprises: numerically solving a volume integral equation for electromagnetic scattering for a plurality of modes in the at least one lateral direction, by performing, for each respective mode, integration (1350) of a pseudo-spectral polynomial (Chebyshev) expansion in the vertical direction multiplied by a ID Green's function using the same sample points in the orthogonal direction for all of the plurality of modes. The integration is performed by solving a regularized linear system of equations between first (1116) and second (1120) discrete transformation steps to compute (1118) values of a regularized Chebyshev expansion coefficient vector (γ). Electromagnetic scattering properties of the structure are calculated using the results of the numerical solution.

A structure in semiconductor fabrication includes at least a first periodic asymmetric feature and a periodic asymmetric second feature. The first feature contains a plurality of periodically distributed first elements. The first feature has a first asymmetric profile such that the first feature no longer has the same first asymmetric profile when it is rotated by 180 degrees. The second feature contains a plurality of periodically distributed second elements. The second feature has a second asymmetric profile such that the second feature no longer has the same second asymmetric profile when it is rotated by 180 degrees. The second asymmetric profile is different from the first asymmetric profile.

According to one embodiment, wafer lithography equipment includes an exposure unit transferring a circuit pattern onto a wafer, a measurement unit measuring a dimension of the circuit pattern and a calculator. The calculator includes calculating a first difference. The first difference is the difference between a first dimension and a second dimension. The first dimension is obtained by substituting a first exposure amount and a first focus distance into an approximate response surface function. The second dimension is measured by the measurement unit. The calculator also includes calculating a second difference. The second difference is the sum total of the first difference for all of the circuit patterns. The calculator also includes calculating a second exposure amount and a second focus distance causing the difference between the approximate response surface function and the second difference to be a minimum. The calculator also includes calculating a correction exposure amount.

An arrangement of a microlithographic optical imaging device includes first and supporting structures. The first supporting structure supports an optical element of the imaging device. The first supporting structure supports the second supporting structure via supporting spring devices of a vibration decoupling device. The supporting spring devices act kinematically parallel to one another between the first and second supporting structures. Each supporting spring device defines a supporting force direction and a supporting length along the supporting force direction. The second supporting structure supports a measuring device configured to measure the position and/or orientation of the optical element in relation to a reference in at least one degree of freedom and up to all six degrees of freedom in space. A creep compensation device compensates a change in a static relative situation between the first and second supporting structures in at least one correction degree of freedom.

An arrangement of a microlithographic optical imaging device includes first and second supporting structures. The first supporting structure supports an optical element of the imaging device. The first supporting structure supports the second supporting structure via supporting spring devices of a vibration decoupling device. The supporting spring devices act kinematically parallel to one another between the first and second supporting structures. Each supporting spring device defines a supporting force direction and a supporting length along the supporting force direction. The second supporting structure supports a measuring device which is configured to measure the position and/or orientation of the at least one optical element in relation to a reference in at least one degree of freedom. A creep compensation device compensates a creep-induced change in a static relative situation between the first and second supporting structures in at least one correction degree of freedom.

In order to provide an imprint device capable of reducing pattern defects, the imprint device which brings a mold into contact with an imprint material on a substrate and transfers a shape of a surface of the mold onto the substrate includes: a mold holding part which holds the mold; a substrate holding part which holds the substrate; and a measuring unit which measures a contact force generated when a part of the mold or the mold holding part is brought into contact with a predetermined contact part, wherein the contact part is installed at a position in a predetermined plane different from a position in the predetermined plane of the substrate held by the substrate holding part and is installed at a height position corresponding to a height of a surface of the substrate held by the substrate holding part.

A metrology system is disclosed, in accordance with one or more embodiments of the present disclosure. The metrology system includes a stage configured to secure a sample, one or more diffraction-based overlay (DBO) metrology targets disposed on the sample. The metrology system includes a light source and one or more sensors. The metrology system includes a set of optics configured to direct illumination light from the light source to the one or more DBO metrology targets of the sample, the set of optics including a half-wave plate, the half-wave plate selectively insertable into an optical path such that the half-wave plate selectively passes both illumination light from an illumination channel and collection light from a collection channel, the half-wave plate being configured to selectively align an orientation of linearly polarized illumination light from the light source to an orientation of a grating of the one or more DBO metrology targets.

A molding apparatus that molds a composition on a substrate with a mold includes a mold holding unit configured to hold the mold, a substrate holding unit configured to hold the substrate, a first elastic member configured to apply a first elastic force to the mold holding unit in a direction away from the substrate holding unit, and a control unit configured to cause the mold holding unit to move in the direction away from the substrate holding unit in a case where the control unit determines that an abnormality has occurred.

Methods and systems for milling and imaging a sample based on multiple fiducials at different sample depths include forming a first fiducial on a first sample surface at a first sample depth; milling at least a portion of the sample surface to expose a second sample surface at a second sample depth; forming a second fiducial on the second sample surface; and milling at least a portion of the second sample surface to expose a third sample surface including a region of interest (ROI) at a third sample depth. The location of the ROI at the third sample depth relative to the first fiducial may be calculated based on an image of the ROI and the second fiducial as well as relative position between the first fiducial and the second fiducial.