A method for monitoring a lithographic process, and associated lithographic apparatus. The method includes obtaining height variation data relating to a substrate supported by a substrate support and fitting a regression through the height variation data, the regression approximating the shape of the substrate; residual data between the height variation data and the regression is determined; and variation of the residual data is monitored over time. The residual data may be deconvolved based on known features of the substrate support.

The alignment apparatus performs alignment of an object in a first direction along a surface of the object, based on a position of a predetermined target formed on the surface, and includes a holding unit that holds the object to be moved, an acquisition unit that acquires an image of the predetermined target formed on the surface of the object held by the holding unit, and a controller that drives the holding unit to realize a relative distance between the object and the acquisition unit in a second direction perpendicular to the surface of the object, a relative tilt between the object and the acquisition unit, or the distance and the tilt, the distance and the tilt being determined based on a correlation degree between the image acquired by the acquisition unit and a template, and detects a position of the predetermined target in the first direction based on the correlation degree.

In a dark-field metrology method using a small target, a characteristic of an image of the target, obtained using a single diffraction order, is determined by fitting a combination fit function to the measured image. The combination fit function includes terms selected to represent aspects of the physical sensor and the target. Some coefficients of the combination fit function are determined based on parameters of the measurement process and/or target. In an embodiment the combination fit function includes jinc functions representing the point spread function of a pupil stop in the imaging system.

The present invention provides a pattern forming apparatus including a detection optical system configured to obtain optical information of a mark provided on a substrate by detecting the mark, and a processing unit configured to perform a process of obtaining a position of the mark by using a template for obtaining the position of the mark by being applied to the optical information of the mark and a window which indicates a region for extracting an amount of characteristic indicating the position of the mark from a waveform signal obtained from the optical information, wherein the processing unit decides, based on the optical information of the mark obtained by the detection optical system, a parameter indicating at least one of a shape of the template and a shape of the window for each of a plurality of substrates.

Multiple model functions may be calculated by detecting alignment marks on a semiconductor wafer structure. The model functions may be combined to determine a combined model function by using a weight function that assigns a different weight to each of basis functions of the model functions. Thus, even when asymmetry of alignment marks or overlay marks has high dependency on a horizontal location on a wafer, reliability of exposure process is insured.

A substrate processing apparatus is provided. The apparatus includes an imaging unit that images a mark on a substrate, and a processor that aligns the substrate based on an image of the mark obtained by the imaging unit. If the alignment has failed, the processor identifies a factor of the failure based on information including the image and executes at least one of a plurality of recovery processes based on the identified factor. The processor includes an output unit that outputs a condition for the at least one of recovery processes in accordance with an inference model, and a learning unit that learns the inference model based on an execution result of the at least one of the recovery processes under the condition output from the output unit.

A lithographic cluster includes a track unit and a lithographic apparatus. The lithographic apparatus includes an alignment sensor and at least one controller. The track unit is configured to process a first lot and a second lot. The lithographic apparatus is operatively coupled to the track unit. The alignment sensor is configured to measure an alignment of at least one alignment mark type of a calibration wafer. At least one controller is configured to determine a correction set for calibrating the lithographic apparatus based on the measured alignment of the at least one alignment mark type and apply first and second weight corrections to the correction set for processing the first and second lots, respectively, such that overlay drifts or jumps during processing the first and second lots are mitigated.

Combination of a stage and a level sensor configured to sense a height level at a target location on an object is described, the stage comprising an object table configured to hold the object and a positioning device for displacing the object table relative to the level sensor in a first direction, the level sensor comprising a projection system configured to project a measurement beam onto a measurement area of the object, the measurement area having a measurement area length in the first direction, a detector system configured to receive different portions of the measurement beam after being reflected off different sub-areas within the measurement area, the different sub-areas being arranged in the first direction, and to supply output signals representative of the different portions received, a signal processing system configured to process the output signals from the detector system.

In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

The present disclosure generally relates to photolithography systems, and methods for correcting positional errors in photolithography systems. When a photolithography system is first started, the system enters a stabilization period. During the stabilization period, positional readings and data, such as temperature, pressure, and humidity data, are collected as the system prints or exposes a substrate. A model is created based on the collected data and the positional readings. The model is then used to estimate errors in subsequent stabilization periods, and the estimated errors are dynamically corrected during the subsequent stabilization periods.