A pre-alignment measurement device includes, disposed in a direction of propagation of light, a laser, a first cylindrical lens, a first imaging lens, an illumination diaphragm, a second imaging lens, a second cylindrical lens and a CCD detector. The laser, an object under measurement and the CCD detector are arranged at respective apexes of a triangle formed by the measurement device for pre-alignment. A light beam is emanated by the laser and is transformed into a line beam. The line beam is reflected by the object under measurement and then passes through the second cylindrical lens to form a CCD image which has different horizontal and vertical magnifications, allowing horizontal and vertical resolutions to be matched with horizontal and vertical measuring ranges, respectively. The CCD image contains information of a position and a height of a step defined by the object under measurement and the wafer stage.

A pattern forming apparatus which forms a pattern on a substrate, which includes a movable stage, a holding unit removably attached to the stage and configured to suck and hold the substrate, an optical system of which position with respect to the holding unit is fixed, and configured to detect an alignment mark of the substrate which is sucked by the holding unit from a suction surface side of the substrate, a reference mark for measuring a position of a detection field of the optical system, and a detection system configured to detect the reference mark. The substrate is disposed on the holding unit in accordance with the position of the reference mark detected by the detection system so that the alignment mark of the substrate detected from the suction surface side of the substrate by the optical system is disposed in the detection field of the optical system.

Aspects of the present disclosure provide a method of aligning a wafer pattern. For example, the method can include providing a wafer having a reference pattern located below a front side of the wafer, and directing a light beam to the wafer. The method can further include identifying at least one of power and a wavelength of the light beam such that the light beam is capable of passing through the wafer and reaching the reference pattern, or identifying at least one of power and a wavelength of the light beam based on at least one of a material of the wafer and a depth of the reference pattern below the front side of the wafer. The method can further include using the light beam to image the reference pattern.

Embodiments of the present invention provide a roll-to-roll exposure system having a reference mark array and alignment scope units for precisely measuring the position and orientation of an object on a flexible multilayered circuit film. A roll-to-roll exposure system according to an exemplary embodiment of the present invention includes: a plurality of rolls configured to move a flexible multilayered circuit film having an object positioned thereon; alignment scope units positioned so as to be spaced apart from each other and proximate to the rolls; and at least one exposure unit positioned so as to be spaced proximate to the rolls and spaced apart from sides of the alignment scope units, in which one of the rolls has a reference mark array on its surface.

The present disclosure provides apparatus and methods for overlay measurement. An exemplary overlay measurement apparatus includes an illuminating unit configured to generate illuminating light to illuminate a first overlay marker formed on a wafer to generate reflected light; and a first measuring unit configured to receive the reflected light from the first overlay marker to cause the reflected light to laterally shift and shear to generate interference light, to receive the interference light to form a first image, and to determine existence of an overlay offset and an exact value of the overlay offset, according to the first image.

While a wafer stage linearly moves in a Y-axis direction, a multipoint AF system detects surface position information of the wafer surface at a plurality of detection points that are set at a predetermined distance in an X-axis direction and also a plurality of alignment systems that are arrayed in a line along the X-axis direction detect each of marks at positions different from one another on the wafer. That is, detection of surface position information of the wafer surface at a plurality of detection points and detection of the marks at positions different from one another on the wafer are finished, only by the wafer stage (wafer) linearly passing through the array of the plurality of detection points of the multipoint AF system and the plurality of alignment systems, and therefore, the throughput can be improved.

A measurement apparatus that measures position information of a measurement target is provided. The apparatus includes a scope configured to generate an image by capturing an image of the measurement target, and a processor configured to obtain position information of the measurement target based on the image. The processor is configured to generate a plurality of image components using a statistical technique from a plurality of images generated by the scope, output the plurality of generated image components, perform processing based on the plurality of image components, and determine the position information based on a result of the processing.

Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

A resonant amplitude grating mark has a periodic structure configured to scatter radiation incident on the mark. The scattering is mainly by coupling of the incident radiation to a waveguiding mode in the periodic structure. The effective refractive indexes and lengths of portions of the periodic structure are configured to provide an optical path length of the unit cell in the direction of periodicity that essentially equals an integer multiple of a wavelength present in the radiation. The effective refractive indexes and lengths of the portions are also configured to provide an optical path length of the second portion in the direction of periodicity that is selected from 0.30 to 0.49 of the wavelength present in the spectrum of the radiation.

An imprint apparatus brings an imprint material on a substrate including a first mark into contact with a mold including a second mark and cures the imprint material, thereby forming a cured product of the imprint material on the substrate. The apparatus includes a plurality of detectors used for alignment detection, and a controller configured to obtain a plurality of pieces of relative position information by detecting a relative position between the first mark and the second mark a plurality of times using the plurality of detectors in a state in which the imprint material is cured and a positional relationship between the substrate and the mold is maintained, and to calibrate, based on the plurality of pieces of relative position information, a plurality of detection processing operations each performed using each of the plurality of detectors.