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.

A system is provided. The system includes an exposing device configured to generate a real-time image, including multiple first align marks, of a mask and an adjusting device configured to adjust an off-set of the mask from a pre-determined position to be smaller than a minimum aligning distance according to the first align marks and multiple align marks on a substrate, and further to move the mask closer to the pre-determined position to have a displacement, less than a minimum mapping distance, from the pre-determined position according to the real-time image and a reference image of the mask.

Systems, apparatuses, and methods are provided for determining the alignment of a substrate. An example method can include emitting a multi-wavelength radiation beam including a first wavelength and a second wavelength toward a region of a surface of a substrate. The example method can further include measuring a first diffracted radiation beam indicative of first order diffraction at the first wavelength in response to an irradiation of the region by the multi-wavelength radiation beam. The example method can further include measuring a second diffracted radiation beam indicative of first order diffraction at the second wavelength in response to the irradiation of the region by the multi-wavelength radiation beam. Subsequently, the example method can include generating, based on the measured first set of photons and the measured second set of photons, an electronic signal for use in determining an alignment position of the substrate.

A method to determine a performance indicator indicative of alignment performance of a processed substrate. The method includes obtaining measurement data including a plurality of measured position values of alignment marks on the substrate and calculating a positional deviation between each measured position value and a respective expected position value. These positional deviations are used to determine a directional derivative between the alignment marks, and the directional derivatives are used to determine at least one directional derivative performance indicator.

The control unit controls the relative position in an optical axis direction of the projection system and the relative position in a direction perpendicular to an optical axis direction at a third timing after a second timing based on a first distribution of illumination light detected by the detection system at a first timing and a second distribution of illumination light detected by the detection system at the second timing after the first timing, the illumination light detected at the first and second timings having passed through the first and second marks.

The present invention provides a method for calculating a corrected substrate height map of a first substrate using a height level sensor. The method comprises: sampling the first substrate by means of the height level sensor with the first substrate moving with a first velocity, wherein the first velocity is a first at least partially non-constant velocity of the first substrate with respect to the height level sensor, to generate a first height level data, generating a first height map based on the first height level data, and calculating a corrected substrate height map by subtracting a correction map from the first height map, wherein the correction map is calculated from the difference between a first velocity height map and a second velocity height map.

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 the 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.

The present invention provides an exposure apparatus that performs an exposure process to transfer a pattern of a mask to a substrate, including a projection optical system configured to project the pattern of the mask onto the substrate, a measurement pattern arranged on an object plane of the projection optical system and including a plurality of pattern elements having different positions in an optical axis direction of the projection optical system, a first detection unit configured to detect light from the measurement pattern via the projection optical system, and a control unit configured to control a relative position between the mask and the substrate in the optical axis direction when the exposure process is performed.

An offset alignment method for a micro-lithographic printing device comprises placing (S10) of an alignment target substrate. A target pattern presents areas of at least two different light reflectivities is defined relative an origin point. The alignment target substrate is illuminated (S20). Reflected light is measured (S30). A reflection image of the target pattern is created (S40) by the measured light. The illumination is made according to a test pattern of light, having areas with and without illumination. The test pattern is defined relative an origin point. A measured target pattern origin point is determined (S50) from target pattern associated features in the reflection image and a measured test pattern origin point is determined from test patterns associated features in the reflection image. An offset between a measured position and a written position is calculated (S60) from the measured target pattern origin point and the measured test pattern origin point.

A calibration method of a detection system including an illumination system configured to illuminate a detection target, and an imaging system configured to form an image of light from the detection target on a photoelectric conversion element, the method including obtaining, for each of at least two combinations of first apertures in the illumination system and second apertures in the imaging system, each of which is formed by selecting one first aperture and one second aperture from the plurality of first apertures and the plurality of second apertures, a defocus characteristic indicating a shift amount of the image on the photoelectric conversion element with respect to a defocus amount of the detection target in a state in which each of the first aperture and the second aperture is positioned in a first position shifted from a reference position.