An alignment sensor for a lithographic apparatus has an optical system configured to deliver, collect and process radiation selectively in a first waveband (e.g. 500-900 nm) and/or in a second waveband (e.g. 1500-2500 nm). The radiation of the first and second wavebands share a common optical path in at least some portion of the optical system, while the radiation of the first waveband is processed by a first processing sub-system and the radiation of the second waveband is processed by a second processing sub-system. The processing subsystems in one example include self-referencing interferometers. The radiation of the second waveband allows marks to be measured through an opaque layer. Optical coatings and other components of each processing sub-system can be tailored to the respective waveband, without completely duplicating the optical system.

Methods and systems for optimizing a set of measurement library control parameters for a particular metrology application are presented herein. Measurement signals are collected from one or more metrology targets by a target measurement system. Values of user selected parameters of interest are resolved by fitting a pre-computed measurement library function to the measurement signals for a given set of library control parameters. Values of one or more library control parameters are optimized such that differences between the values of the parameters of interest estimated by the library based measurement and reference values associated with trusted measurements of the parameters of interest are minimized. The optimization of the library control parameter values is performed without recalculating the pre-computed measurement library. Subsequent library based measurements are performed by the target measurement system using the optimized set of measurement library control parameters with improved measurement performance.

A lithographic apparatus having a substrate table, a projection system, an encoder system, a measurement frame and a measurement system. The substrate table has a holding surface for holding a substrate. The projection system is for projecting an image on the substrate. The encoder system is for providing a signal representative of a position of the substrate table. The measurement system is for measuring a property of the lithographic apparatus. The holding surface is along a plane. The projection system is at a first side of the plane. The measurement frame is arranged to support at least part of the encoder system and at least part of the measurement system at a second side of the plane different from the first side.

What is proposed is an apparatus for analysing and/or processing a sample with a particle beam, comprising:

a providing unit for providing the particle beam; and

a test structure attached to the providing unit;

wherein the apparatus is configured for implementing an etching process and/or a deposition process on the test structure using the particle beam.

A first stage system having a first stage and a first drive system that moves the first stage is configured to hold a mask illuminated with illumination light. A second stage system having a second stage and a second drive system that moves the second stage is configured to hold a substrate. A measurement system having a first encoder system and a second encoder system measures positional information of the first and second stages, respectively. The second encoder system measures the positional information of the second stage with a plurality of heads that face a grating section. The first and second drive systems are controlled while compensating for a measurement error that occurs due to at least one of a gradient and a telecentricity of the head, based on correction information.

A movement area of a stage includes first-fifth areas. In the first area, three of four heads except for a first head respectively face three of four sections of a scale member except for a first section. In the second area, three of four heads except for a second head respectively face three of four sections except for a second section of the scale member. In the third area, three of four heads except for a third head respectively face three of four sections except for a third section of the scale member. In the fourth area, three of four heads except for a fourth head respectively face three of four sections of the scale member. In the fifth area, the four heads respectively face the four sections. The stage is moved from one of the first-fourth areas to another of those areas via the fifth area.

A first stage system having a first stage and a first drive system that moves the first stage is configured to hold a mask illuminated with illumination light. A second stage system having a second stage and a second drive system that moves the second stage is configured to hold a substrate. A measurement system having a first encoder system and a second encoder system measures positional information of the first and second stages, respectively. The second encoder system measures the positional information of the second stage with a plurality of heads that face a grating section. The first and second drive systems are controlled while compensating for a measurement error that occurs due to at least one of a gradient and a telecentricity of the head, based on correction information.

At least one lithography apparatus that suppresses a decrease in the accuracy of stage control is provided. A lithography apparatus includes a moving unit configured to move with an original or a substrate mounted thereon, a plurality of measurement units configured to obtain information about a position of the moving unit, measurement areas of the respective measurement units overlapping each other, and a control unit configured to switch the measurement units used to obtain the information about the position of the moving unit, based on a switching position lying in an overlapping measurement area, wherein, in a case where a plurality of processes is performed on one of a plurality of processing targets on the original or on the substrate, the control unit makes the switching position changeable and controls the measurement units so that the same one of the measurement units is used in performing the plurality of processes.

Correction information is acquired for compensating for a measurement error of a second encoder system that occurs due to a displacement between four sections of a scale member of the second encoder system, based on measurement information of the second encoder system obtained in a fifth area in which four heads of the second encoder system that are provided on a second stage, which holds a substrate, respectively face the four sections of the scale member.

A method for determining a mechanical property of a layer applied to a substrate and associated control system for controlling a lithographic process. The method includes obtaining measured out-of-plane deformation of the substrate, the out-of-plane deformation including deformation normal to a substrate plane defined by, or parallel to, a substrate surface. The measured out-of-plane deformation is fitted to a second order polynomial in two coordinates associated with the substrate plane and the mechanical property (e.g. anisotropic Young's moduli) of the layer is determined based on characteristics of the fitted second order polynomial. The mechanical property of the layer can be used to calibrate an in-plane distortion model of the substrate for predicting in-plane distortion based on the measured out-of-plane deformation.