Abstract: An exposure method according to the present invention includes a first step of forming on a substrate an alignment mark including a concave and convex pattern; a second step of forming a coat over said alignment mark and the other area on said substrate; a third step of flattening said coat; and a fourth step of applying a photosensitive material on said coat flattened by said third step and projecting a mask pattern thereto. The alignment mark is formed by said concave and convex pattern arranged with a pitch which is smaller than the predetermined value between adjacent convex portions having a width of not less than a predetermined value.

Abstract: An exposure apparatus exposes a pattern formed on a mask to a substrate having an alignment with a difference in level and a photosensitive material applied on the surface of the substrate. The exposure apparatus includes a stage adapted to hold the substrate and two-dimensionally movable in a predetermined plane; a sensor held in a predetermined relationship with respect to the plane and outputting a signal which varies in response to a relative movement between the sensor and the substrate in a direction perpendicular to the plane; a position detecting device for detecting the position of the stage; an arithmatic unit for calculating the position of the alignment mark on the basis of information from the position detecting device and an output outputted from the sensor when the stage and the sensor are moved relative to each other; and a control system for controling movement of the stage on the basis of the position of the alignment mark.

Abstract: A projection exposure apparatus controls the position of a mask so that the mask is in a desired position without reducing throughput even if the size of the mask is increased. For example, a controller adjusts the pressure of air blown from air holes so that a reticle is floated at a desired distance above a reticle floating plate. The controller also controls the driving of linear motors having stators and sliders, thereby adjusting the pressing force of control bars in contact with the sides of the floating reticle to press the sides of the reticle and control the two-dimensional position of the reticle. Therefore, it is possible to control a mask so that the mask is placed in a desired position without reducing throughput.

Abstract: The present invention aims to provide a method of measuring an image-forming error of a projection lens without being influenced by atmospheric temperature at the time of coordinate measurement, and various kinds of applied techniques employing this measuring method. In particular, the measuring method according to the present invention enables errors to be measured with a high accuracy, while taking account of the temperature-dependent extraction or contraction component of the substrate, which is used for measuring the image-forming error.

Abstract: Disclosed is a method to measure the actual exposure image of an evaluation pattern on a reticle with increased the accuracy to determine the best focus position. An evaluation mark is formed on a reticle. The evaluation mark is comprised of an arrangement in a lattice form (regular geometric arrangement) in the measurement direction, of multiple basic marks formed by the arrangement in the non-measurement direction of multiple wedge-shaped marks, which are pointed in the measurement direction. While the focus position of the wafer is changed and while the wafer is laterally shifted, the image of the evaluation mark is transferred onto the wafer. After the wafer is developed, the position of the image of the evaluation mark is measured by means of an alignment sensor. The center position of the image of the evaluation mark shifts towards the point of the wedge-shaped marks the closer the surface of the wafer comes to the best focus position.

Abstract: A projection exposure system for printing the pattern formed on a reticle onto a wafer includes a reticle stage (5) and a wafer stage. A first reference plate (9) having a first reference pattern (MM1) formed thereon is mounted on the reticle stage (5), and a second reference plate (25) having a second reference pattern (WM1) formed thereon is mounted on the wafer stage. The first reference pattern (MM1) comprises two cross-marks (60a, 60b) spaced apart from each other in X-direction, and the second reference pattern (WM1) comprises two cross-marks (61a, 61b) spaced apart from each other in X-direction., Images of the cross-marks (61a, 61b) of the second reference pattern (WM1) are formed through a projection optical system (2) on the reticle stage (5) and superimposed with the cross-marks (60a, 60b) of the first reference pattern (MM1).

Abstract: A plurality of pairs of alignment marks are formed on a reticle along a scanning direction, and, when a first wafer is to be exposed, a base line amount of an alignment sensor is measured by using a first pair of alignment marks (steps 112, 113, 115), and, when a second wafer is to be exposed, the base line amount is measured by using a second pair of alignment marks and a magnification error of the reticle in the scanning direction is determined on the basis of positional displacement amounts of the alignment marks measured regarding the first wafer and positional displacement amounts of the alignment marks measured regarding the second wafer (step 115), whereby the magnification error of the reticle in the scanning direction is measured with high accuracy, without making a measuring device complicated and reducing through-put of the exposure process.

Abstract: A projection exposure apparatus for positioning, for each shot provided on a wafer, a pattern formed on a mask with respect to the wafer and also for exposing the pattern on the wafer includes a wafer stage carrying the wafer and movable stepwise for each shot, a mask stage carrying the mask and movable, a stage control unit for making relative positioning between the wafer and the pattern of the mask and maintaining the relative positioning so that the stage control unit moves the mask stage to make the relative positioning before the wafer stage stops for each shot, and an exposure control unit for performing exposure while the relative positioning is maintained.

Abstract: Provided is a method of aligning a substrate pattern on a photosensitive surface of a substrate with an image of a mask pattern to be formed on the photosensitive surface by an exposing radiation flux through a projection optical system in a projection exposure apparatus, using an alignment sensor system detecting a positional relationship between the substrate pattern and the image.

Abstract: In a projection exposure apparatus for projecting an image of a pattern on a reticle through a projection optical system onto a wafer, in order to quickly measure imaging characteristics of the projection optical system without actual exposure, an enlarging optical system consisting of an objective lens and a relay optical system, and an image pickup element are provided on a Z-stage on which the wafer is mounted. Illumination light illuminates an index pattern formed on the reticle to form an image thereof near a first lens in the objective lens through the projection optical system, the enlarging optical system enlarges the thus formed image of the index pattern to form an enlarged image thereof on a receiving surface of the image pickup element, the image pickup element converts it into a signal, and an image processing system processes the signal from the image pickup element, thereby measuring the imaging characteristics of the projection optical system, based on the processing results.

Abstract: An alignment method in which a plurality of areas on a wafer which are to be exposed are each aligned with respect to a reference position. The method includes: measuring array coordinates of a plurality of alignment measuring points; determining a reliability value for each alignment datum on the basis of a dispersion of differences (alignment data) between the measured array coordinates and the corresponding design values; calculating values of coordinate transformation parameters for obtaining actual array coordinates from the design array coordinates by using the reliability value as a weight; and obtaining array coordinates of each shot area by using the transformation parameters.

Abstract: In a position detecting apparatus, a light beam from a white light source is guided through a collimator lens etc. to be converted into a parallel beam, and this parallel beam is incident to a first acousto-optic modulator (AOM) and a second acousto-optic modulator positioned with a spacing by which a phase difference between diffracted light is approximately m.sup..pi. (where m is an integer). Traveling waves of slightly different frequencies opposite to each other are supplied in opposite directions to the two acousto-optic modulators, and the position detecting apparatus executes position detection by the heterodyne interference method as guiding a beam comprised of +first-order diffracted light from the acousto-optic modulators and a beam comprised of -first-order diffracted light from the acousto-optic modulators through an objective lens to project them with a predetermined intersecting angle onto a diffraction grating mark.

Abstract: An alignment method in which a reticle and a wafer are aligned with each other by using a heterodyne alignment apparatus. The method makes it possible to minimize the time required for alignment even if a wafer beat signal varies for each shot region on the wafer. In pre-alignment of the wafer, AGC (Automatic Gain Control) of a wafer beat signal (S.sub.W) is initiated when a central control system confirms that the displacement between the center of a wafer mark and the center of an irradiation region of an alignment light beam irradiated to the wafer has reached a value within .+-..DELTA.L.sub.1 in the measuring direction (direction X) and a value within .+-..DELTA.L.sub.2 in the non-measuring direction (direction Y) on the basis of the result of calculation by an overlap calculating system, before the displacement between the reticle and a grating-shaped wafer mark reaches a value within .+-.1/4 of a grating pitch (P.sub.W).

Abstract: The X-coordinate of an X-axis search alignment mark (GMX) on a wafer (6) and the Y-coordinates of Y-axis search alignment marks (GMY1 and GMY2) on the wafer (6) are measured by laser step alignment (LSA) method, and the results of the measurement are processed to calculate approximate array coordinates of shot areas (ES1 to ES21) on the wafer (6). Die-by-die alignment and exposure are initiated from the shot area (ES11) that is the closest to the center of the array of all search alignment marks by using a TTR and two-beam interference (LIA) type alignment sensor having a predetermined capture range. At a shot area to be subsequently exposed, the amount of positional displacement between the reticle and the wafer is made to fall within the capture range relative to the initial positional displacement, thereby enabling alignment of high accuracy.

Abstract: In an alignment apparatus for aligning a mask and a photosensitive substrate (a semiconductor wafer or glass plate applied with a photoresist), and which is suitably used in a projection exposure apparatus (a stepper or aligner), a proximity exposure apparatus, or the like used in a lithography process in the manufacture of a semiconductor element or a liquid crystal display element, two first beams and two second beams differing from the first beams may be radiated on a diffraction grating-like mask mark and a diffraction grating-like substrate mark, respectively, with the two second beams passing through a transparent region adjacent to the mask mark. By detecting diffracted light components of the two first beams and detecting diffracted light components of the two second beams, a relative position shift between the mask and the substrate can be determined.

Abstract: Two-colored illumination light emitted from first and second laser beam sources illuminates a reticle mark and a wafer mark. Diffraction light from the reticle mark and the wafer mark is received by two photoelectric detection elements, respectively. The one photoelectric element receives single-colored diffraction light from light of the first light source through a color filter to generate a reticle beat signal. The other photoelectric element receives two-colored light to generate a wafer beat signal. A phase difference between the reticle beat signal and the wafer beat signal when shutting off the second laser beam source is aligned with a phase difference between the two signals produced when turning on the second laser beam source and decreasing the power of the first laser light source.

Abstract: An exposure method according to the present invention includes a first step of forming on a substrate an alignment mark including a concave and convex pattern; a second step of forming a coat over said alignment mark and the other area on said substrate; a third step of flattening said coat; and a fourth step of applying a photosensitive material on said coat flattened by said third step and projecting a mask pattern thereto. The alignment mark is formed by said concave and convex pattern arranged with a pitch which is smaller than the predetermined value between adjacent convex portions having a width of not less than a predetermined value.

Abstract: A position detecting apparatus comprises a double-beam producing device for producing two beams different in frequency from each other, which are guided to irradiate a diffraction grating on an object to be inspected in two predetermined directions, and a detector photoelectrically detecting through an objective optical system diffracted light produced by the diffraction grating, in which the double-beam producing device comprises a light source for supplying a beam of a single wavelength or multiple wavelengths, a beam splitting device for splitting the beam from the light source into two predetermined beams, a relay optical system for converging the two split beams at a predetermined position, and a frequency difference producing device disposed at or near a converging position by the relay optical system, for producing a predetermined frequency difference between the two split beams.

Abstract: The structure of an alignment apparatus is as follows: The illuminating areas of the two laser beams for the use of alignment, which are irradiated onto a diffraction grating on a substrate and a diffraction grating mark on a fiducial member, are relatively driven by a field diaphragm and a diaphragm member. A photoelectric detector receives the interference light generated from a first portion in the area on the above-mentioned diffraction mark where the two laser beams intersect following the above-mentioned relative driving, and receives the interference light generated from a second portion in the aforesaid area. A main control system calculates the intersecting angles or rotational error of the two laser beams on the basis of the phase difference of the detection signals from the aforesaid photoelectric detector. The intersecting angles or rotational error is corrected by allowing the parallel flat glasses, which are arranged on the light path, to be slanted.

Abstract: Plural shot areas arranged in succession in a two-dimensional array on a substrate are aligned to a predetermined reference position in a fixed coordinate system. At least three of the plural shot areas are selected as specified shot areas. Coordinate values (positions) of alignment marks associated, respectively, with the specified shot areas are measured. Anticipated coordinate values are calculated from preset coordinate values, based on an array model of the shot areas, predetermined by a first equation. A unique relation defined by a second equation is assumed, between the anticipated coordinate values and actual coordinate values in the alignment. Parameters of the relation are determined so as to minimize the average error between the measured coordinate values and coordinate values calculated from the relation. Actual coordinate values of the shot areas on the substrate are calculated based on the parameters and the anticipated coordinate values.