A method for determining a center of a radiation spot irradiated on a surface by a sensor, the sensor including a radiation source and a detector. The method includes: emitting, with the radiation source, a first emitted radiation beam onto the surface to create the radiation spot on the surface, wherein at least a part of a target arranged at the surface is irradiated by the radiation spot; receiving, with the detector, a first reflected radiation beam at least including radiation from the radiation spot reflected by the target; detecting the presence of the target based on the first reflected radiation beam; determining a first measured position of the target based on the first reflected radiation beam; and determining a center of the radiation spot as projected on the surface in at least a first direction based on the first measured position of the target.

The present invention provides a measurement apparatus that includes a movable stage and measures a position of a mark on the stage, comprising an imaging device including a plurality of pixels arranged at a pitch and imaging the mark, a driving device changing a relative position between the stage and the imaging device, a measurement device measuring the relative position, and a processor obtaining the position of the mark based on a plurality of images respectively obtained by the imaging device at a plurality of relative positions between the stage and the imaging device that are different from each other and associated with the pitch, wherein the processor is configured to obtain, based on a deviation with respect to one of the plurality of relative positions, a target relative position with respect to another of the plurality of relative positions.

A lithographic process is used to form a plurality of target structures (T) on a substrate (W). Each target structure comprises overlaid gratings each having a specific overlay bias. Asymmetry (A) of each grating, measured by scatterometry, includes contributions due to (i) the overlay bias, (ii) an overlay error (OV) in the lithographic process and (iii) bottom grating asymmetry within the overlaid gratings. Asymmetry measurements are obtained for three or more target structures having three or more different values of overlay bias (e.g., −d, 0, +d). Knowing the three different overlay bias values and a theoretical curve relationship between overlay error and asymmetry, overlay error (OV) can be calculated while correcting the effect of bottom grating asymmetry. Bias schemes with three and four different biases are disclosed as examples. Gratings with different directions and biases can be interleaved in a composite target structure.

A method calibrates a laser processing machine by commanding a scan head to direct a laser beam to a desired position, then senses an actual position of the laser beam directly using a position sensitive detector (PSD) after the scan head is positioned. A relative position between the scan head and PSD is altered using one or more linear actuators. A position feedback loop is closed around the linear actuators so that the relative position of the laser beam on the PSD is reduced to zero. The actual position of the laser spot is then measured indirectly by encoders attached to linear axes of the laser processing machine. The actual position is stored in a memory. An error is determined as a difference between the desired position and the actual position. Compensation coefficients are determined from the error and stored for later use during operation of the laser processing machine.

A position detection apparatus configured to detect a pattern including a plurality of pattern elements formed on an object includes a control unit configured to detect the pattern by performing pattern matching between a template including a plurality of feature points and the plurality of pattern elements. While, performing pattern matching, the control unit changes positions of the plurality of feature points such that a correlation between an image and the template is within a predetermined allowable range.

The present invention provides a lithography apparatus which performs a process of forming a pattern on a substrate conveyed from a coating apparatus which coats the substrate with a resist, the lithography apparatus including an obtaining unit configured to obtain, from the coating apparatus, first specifying information which specifies a processing target substrate conveyed from the coating apparatus to the lithography apparatus, out of a plurality of substrates which are coated with the resist by the coating apparatus and on which the process is to be performed, and a processing unit configured to select offset correction information corresponding to the processing target substrate from a plurality of pieces of offset correction information respectively corresponding to the plurality of substrates based on the first specifying information and perform the process on the processing target substrate by using the selected offset correction information.

A system is disclosed. The system includes a cleaning device and a scanner device. The cleaning device is configured to clean a mask. The scanner device is coupled to the cleaning device and is configured to receive the mask, a reference image and a real-time image that is captured at the mask. The reference image includes at least one first mark image having a plurality of mapping marks on the mask. The real-time image includes at least one second mark image having the plurality of mapping marks on the mask. The scanner device is configured to map the at least one second mark image in the real-time image with the at least one first image in the reference image, when a lithography exposing process is performed. A method is also disclosed herein.

A lithographic apparatus includes an illumination system to produce a beam of radiation, a support to support a patterning device to impart a pattern on the beam, a projection system to project the patterned beam onto a substrate, and a metrology system that includes a radiation source to generate radiation, an optical element to direct the radiation toward a target, a detector to receive a first and second radiation scattered by the target and produce a first and second measurement respectively based on the received first and second radiation, and a controller. The controller determines a correction for the first measurement, an error between the correction for the first measurement and the first measurement, and a correction for the second measurement based on the correction for the first measurement, the second measurement, and the error. The lithographic apparatus uses the correction to adjust a position of a substrate.

A method for detecting a mark using a detection apparatus including a detection unit includes performing a first movement process that moves the detection unit to a first position, performing a second movement process that moves the detection unit to a second position, detecting the mark after the first movement process and the second movement process, and correcting a measurement value of the detected mark using first information about a movement of the detection unit in the first movement process and second information about a movement of the detection unit in the second movement process.

A lithographic apparatus includes an illumination system to produce a beam of radiation, a support to support a patterning device to impart a pattern on the beam, a projection system to project the patterned beam onto a substrate, and a metrology system that includes a radiation source to generate radiation, an optical element to direct the radiation toward a target, a detector to receive a first and second radiation scattered by the target and produce a first and second measurement respectively based on the received first and second radiation, and a controller. The controller determines a correction for the first measurement, an error between the correction for the first measurement and the first measurement, and a correction for the second measurement based on the correction for the first measurement, the second measurement, and the error. The lithographic apparatus uses the correction to adjust a position of a substrate.