Methods and apparatuses for estimating at least part of a shape of a surface of a substrate usable in fabrication of semiconductor devices. Such a method includes: obtaining at least one focal position of the surface of the substrate measured by an inspection apparatus, the at least one focal position for bringing targets on or in the substrate within a focal range of optics of the inspection apparatus; and determining the at least part of the shape of the surface of the substrate based on the at least one focal position.

A semiconductor tool includes an illumination source to generate an illumination beam, one or more illumination optical elements to direct a portion of the illumination beam to a sample, a detector, one or more collection optical elements to direct radiation emanating from the sample to the detector, and a controller communicatively coupled to the detector. The controller is configured to measure alignment at a plurality of locations across the sample to generate alignment data, select an analysis area for alignment zone determination, divide the analysis area into two or more alignment zones having different alignment signatures; model the alignment data of at least a first alignment zone of the two or more alignment zones using a first alignment model, and model the alignment data of at least a second alignment zone of the two or more alignment zones using a second alignment model different than the first alignment model.

Metrology measurements are performed on substrates that have been subjected to lithographic processing. Model parameters are calculated by fitting the measurements to an extended high-order substrate model defined using a combination of basis functions that include an edge basis function related to a substrate edge. A radial edge basis function may be expressed in terms of distance from a substrate edge. The edge basis function may, for example, be an exponential decay function or a rational function. Lithographic processing of a subsequent substrate is controlled using the calculated high-order substrate model parameters, in combination with low-order substrate model parameters obtained by fitting inline measurements to a low order model.

A method of processing a wafer is provided. The method includes providing a reference pattern for patterning a wafer. The reference pattern is independent of a working surface of the wafer. A placement of a first pattern on the working surface of the wafer is determined by identifying the reference pattern to align the first pattern. The first pattern is formed on the working surface of the wafer based on the placement.

Measurements are obtained from locations across a substrate before or after performing a lithographic process step. Examples of such measurements include alignment measurements made prior to applying a pattern to the substrate, and measurements of a performance parameter such as overlay, after a pattern has been applied. A set of measurement locations is selected from among all possible measurement locations. At least a subset of the selected measurement locations are selected dynamically, in response to measurements obtained using a preliminary selection of measurement locations. Preliminary measurements of height can be used to select measurement locations for alignment. In another aspect, outlier measurements are detected based on supplementary data such as height measurements or historic data.

A measurement system used in a manufacturing line for micro-devices includes: a plurality of measurement devices in which each device performs measurement processing on a substrate; and a carrying system to perform delivery of a substrate with the plurality of measurement devices. The plurality of measurement devices includes a first measurement device that acquires position information on a plurality of marks formed on a substrate, and a second measurement device that acquires position information on a plurality of marks formed on a substrate. Position information on a plurality of marks formed on a substrate can be acquired under a setting of a first predetermined condition in the first measurement device, and position information on a plurality of marks formed on another substrate can be acquired under a setting of a second predetermined condition different from the first predetermined condition in the second measurement device.

According to one embodiment, a value of a film thickness of a processing object disposed above a substrate is obtained. Then, a wavelength that provides a highest degree of intensity of signal light reflected when the signal light is incident onto the processing object having the value of the film thickness, based on wavelength selection reference information is selected. Then, a first instruction performing an alignment process to the substrate by use of signal light having a wavelength thus selected is generated. The wavelength selection reference information is information that includes a correlation between values of the film thickness of the processing object and degrees of intensity of the signal light, with respect to a plurality of wavelengths.

A lithographic apparatus includes an alignment sensor including a self-referencing interferometer for reading the position of a mark including a periodic structure. An illumination optical system focuses radiation of different colors and polarizations into a spot which scans said structure. Multiple position-dependent signals are detected in a detection optical system and processed to obtain multiple candidate position measurements. Each mark includes sub-structures of a size smaller than a resolution of the optical system. Each mark is formed with a positional offset between the sub-structures and larger structures that is a combination of both known and unknown components. A measured position of at least one mark is calculated using signals from a pair of marks, together with information on differences between the known offsets, in order to correct for said unknown component of said positional offset.

A photolithography alignment method includes: performing alignment measurement of a surface condition of a wafer to obtain alignment information of the wafer; and sectioning the wafer into a plurality of areas to be processed according to the alignment information, and determining photolithography alignment parameters corresponding to each area to be processed.

A method and device for enhancing alignment performance of a lithographic device can provide an optimal alignment light source type to perform alignment according to product features. Overlay performance of the product can be improved, wafer reject can be reduced, and production efficiency can be enhanced.