JP5050078B2 - Pattern inspection device - Google Patents

Description

  The present invention relates to a pattern inspection apparatus for inspecting defects (for example, disconnection, thinning, or adhesion of foreign matter) in a pattern formed on a sample of a photomask or a silicon wafer used for manufacturing a semiconductor.

  Along with the high integration of semiconductor devices such as LSI, masks such as reticles and silicon wafers have been miniaturized. Therefore, a high-performance pattern inspection apparatus is also required. As an inspection apparatus, an apparatus that detects a defect by capturing a pattern of an object with a high-precision optical system and an image sensor such as a CCD and comparing the captured image with a reference image has been put into practical use.

  Here, in a conventional pattern inspection apparatus, an optical image obtained by imaging a pattern formed on a sample such as a lithography mask using a magnifying optical system at a predetermined magnification and an identical pattern on the sample are captured. It is known to perform an inspection by comparing with an optical image (for example, see Patent Document 1). For example, as a pattern inspection method, a “die to die inspection” method in which optical image data obtained by imaging the same pattern at different locations on the same mask is compared, or a CAD used for drawing a mask pattern Image data (reference image data) that is used as a reference for comparison is generated based on drawing data (design data) obtained by converting the data into the inspection device input format, and this is compared with optical image data that is used as measurement data obtained by imaging the pattern. There is a “die to database inspection” method. In the inspection method in such an inspection apparatus, the sample is placed on the stage, and the stage is moved so that the light beam scans on the sample and the inspection is performed. The sample is irradiated with a light beam by a light source and an illumination optical system. The light transmitted or reflected by the sample is imaged on the sensor via the optical system. The image picked up by the sensor is sent to the comparison circuit as optical image (measurement image) data. In the comparison circuit, the reference image data and the optical image data are compared according to an appropriate algorithm after the images are aligned, and if they do not match, it is determined that there is a pattern defect.

  With the miniaturization of conductors, the performance required for inspection devices is increasing year by year. In order to accurately measure the position of the pattern imaged in the inspection apparatus, it is necessary to exclude the displacement factor generated in the optical system in addition to the highly accurate position measurement of the object. The object scans on a stage driven in the X and Y directions. The position of the object is measured by a length measuring system such as a laser interferometer, and is referred to when compared with a reference image. Light emitted from the object is imaged on the image sensor by the imaging system.

  Generally, in order to acquire a high-resolution image, the imaging system of the inspection apparatus is an enlargement system. Therefore, it is necessary to combine a lens with a long focal length, and the optical path length is inevitably increased. Therefore, the situation is easily affected by air fluctuation. Since the air fluctuation corresponds to a change in the refractive index distribution in the optical path, it works as an effect of bending the light beam. As a result, the pattern image is displaced on the image sensor. Since this displacement becomes an error when compared with the reference image, it becomes a factor that hinders high-precision inspection.

JP 2008-233342 A

  An object of the present invention is to reduce inspection errors due to air fluctuations in pattern inspection.

  A pattern inspection apparatus according to an aspect of the present invention includes a slit plate in which first and second openings are formed, an illumination optical system that irradiates illumination light through the slit plate, and a part of the illumination light. A transflective plate that reflects and passes the remainder of the illumination light toward the patterned object surface; a first image reflected by the transflective plate; and a first image reflected by the object surface An imaging optical system that forms two images, a displacement measurement sensor that measures the displacement of the first partial image that has passed through the first opening in the first image, and the second An image sensor that captures a second partial image that has passed through the second opening, and a reference image generation circuit that generates a reference image for comparison with an optical image of the second partial image; An arithmetic circuit for calculating a displacement amount of the position of the first partial image and a displacement amount of the position of the first partial image are used. Te, characterized by comprising a comparison circuit for comparing said optical image with the reference image.

  A pattern inspection apparatus according to another aspect of the present invention includes a slit plate having first and second openings, an illumination optical system that irradiates illumination light through the slit plate, and the illumination light. A beam splitter branched by passing and reflecting; a reflecting plate reflecting a part of the illumination light reflected by the beam splitter; a first image reflected by the reflecting plate; and passing through the beam splitter; An imaging optical system that forms an image of the second image formed by the remainder of the illumination light reflected by the patterned object surface, and the first image of the first image that has passed through the first opening. A displacement measuring sensor that measures the displacement of one partial image, an imaging sensor that captures a second partial image that has passed through the second opening in the second image, and the second partial image A reference image generation circuit for generating a reference image for comparison with an optical image; An arithmetic circuit that calculates a displacement amount of the position of the first partial image; and a comparison circuit that compares the optical image with the reference image using the displacement amount of the position of the first partial image. It is characterized by that.

  A pattern inspection apparatus according to another aspect of the present invention includes a slit plate having first and second openings, an illumination optical system that irradiates illumination light through the slit plate, and the illumination light. A beam splitter branched by passing and reflecting; a reflecting plate reflecting a part of the illumination light that has passed through the beam splitter; a first image reflected by the reflecting plate; and a pattern reflected by the beam splitter, An imaging optical system that forms an image of the second image formed by the remaining portion of the illumination light reflected by the formed object surface, and the first of the first images that has passed through the first opening. A displacement measurement sensor for measuring the displacement of the partial image of the second image, an imaging sensor for capturing the second partial image of the second image that has passed through the second opening, and optics of the second partial image. A reference image generation circuit for generating a reference image for comparison with the image; Using the arithmetic circuit for calculating the displacement amount of the position of the first partial image measured by the displacement measurement sensor, and using the displacement amount of the position of the first partial image, the optical image and the reference image are obtained. And a comparison circuit for comparison.

  A pattern inspection apparatus according to another aspect of the present invention includes a slit plate in which first and second openings are formed, an illumination optical system that irradiates illumination light through the slit plate, and the illumination light First and second transflective plates that partially reflect and pass the remainder of the illumination light to the patterned object surface side, and the first reflected by the first transflective plate An imaging optical system that forms an image, a second image reflected by the object surface, and a third image reflected by the second transflective plate; and A first displacement measuring sensor for measuring the displacement of the first partial image that has passed through the first opening, and a second portion of the second image that has passed through the second opening. An image sensor that captures an image, and a second displacement measurement unit that measures a third partial image that has passed through the first opening, among the displacements of the third image. A reference image generation circuit that generates a reference image for comparison with the optical image of the second partial image, a displacement amount of the position of the first and third partial images, and a magnification of the second partial image An arithmetic circuit that calculates a change value, and a comparison circuit that compares the optical image with the reference image using the displacement amount and the magnification change value are provided.

  A pattern inspection apparatus according to another aspect of the present invention includes a slit plate having first and second openings, an illumination optical system that irradiates illumination light through the slit plate, and the illumination light. A beam splitter that branches by passing and reflecting; and a transflective reflector that reflects a part of the part of the illumination light reflected by the beam splitter and passes the remaining part of the part of the illumination light; A reflection plate that reflects the remainder of the illumination light that has passed through the transflective plate, a first image reflected by the transflective plate, and an object that has been patterned through the beam splitter An imaging optical system that forms a second image by the remaining part of the illumination light reflected by the object surface and a third image reflected by the reflector, and the first image among the first images. A first displacement measurement unit that measures the displacement of the first partial image that has passed through one opening. An image sensor that captures a second partial image that has passed through the second opening in the second image, and a second sensor that has passed through the first opening in the third image. A second displacement measurement sensor that measures the displacement of the third partial image, a reference image generation circuit that generates a reference image for comparison with the optical image of the second partial image, and the first and third portions An arithmetic circuit for calculating a displacement amount of the image position, a magnification change value of the second partial image, a comparison circuit for comparing the optical image and the reference image using the displacement amount and the magnification change value; , Provided.

  A pattern inspection apparatus according to another aspect of the present invention includes a slit plate having first and second openings, an illumination optical system that irradiates illumination light through the slit plate, and the illumination light. A beam splitter that branches by passing and reflecting; a transflective reflector that reflects a part of the part of the illumination light that has passed through the beam splitter and passes the remaining part of the part of the illumination light; A reflector that reflects the remainder of the part of the illumination light that has passed through the semi-transmissive reflector, a first image reflected by the semi-transmissive reflector, and a beam that is reflected by the beam splitter and patterned. An imaging optical system that forms a second image of the remainder of the illumination light reflected by the object surface and a third image reflected by the reflector, and among the first image, A first displacement meter that measures the displacement of the first partial image that has passed through the first opening. A sensor; an image sensor that captures a second partial image that has passed through the second opening in the second image; and a second sensor that has passed through the first opening in the third image. A second displacement measurement sensor that measures the displacement of the third partial image, a reference image generation circuit that generates a reference image for comparison with the optical image of the second partial image, and the first and third portions An arithmetic circuit that calculates a displacement amount of the image position and a magnification change value of the second partial image, and a comparison circuit that compares the optical image with the reference image using the displacement amount and the magnification change value; , Provided.

  Pattern inspection with reduced influence caused by air fluctuation can be performed.

It is a conceptual diagram of the pattern inspection apparatus 100-1 of Embodiment 1. FIG. It is a conceptual diagram of a slit board. FIG. 6 is a virtual diagram in which a first image and a second image are formed on the same plane. It is a conceptual diagram of the configuration of a reference pattern and a displacement measurement sensor. It is a conceptual diagram of the configuration of a reference pattern and a displacement measurement sensor. It is a conceptual diagram of the pattern inspection apparatus 100-2 of Embodiment 2. FIG. It is a conceptual diagram of the pattern inspection apparatus 100-3 of Embodiment 3. It is the virtual diagram which formed the 1st, 3rd, and 2nd image on the same surface. It is a conceptual diagram of the pattern inspection apparatus 100-4 of the modification of Embodiment 3. FIG. It is a conceptual diagram of the pattern inspection apparatus 200-1 of Embodiment 4. It is a conceptual diagram of the pattern inspection apparatus 200-2 of the modification of Embodiment 4. It is a conceptual diagram of the pattern inspection apparatus 200-3 of Embodiment 5. It is a conceptual diagram of the pattern inspection apparatus 200-4 of the modification of Embodiment 5. FIG. It is a conceptual diagram of the pattern inspection apparatus 300-1 of Embodiment 6. It is a conceptual diagram of the pattern inspection apparatus 300-2 of the modification of Embodiment 6. FIG. It is a conceptual diagram of the pattern inspection apparatus 300-3 of Embodiment 7. It is a conceptual diagram of the pattern inspection apparatus 300-4 of the modification of Embodiment 7. FIG. It is a conceptual diagram of the pattern inspection apparatus 400-1 of Embodiment 8. It is a conceptual diagram of the pattern inspection apparatus 400-2 of the modification of Embodiment 8. It is a conceptual diagram of the pattern inspection apparatus 400-3 of Embodiment 9. It is a conceptual diagram of the pattern inspection apparatus 400-4 of the modification of Embodiment 9.

(Embodiment 1)
FIG. 1 is a conceptual diagram of pattern inspection apparatus 100-1 in the first embodiment.
In FIG. 1, a pattern inspection apparatus 100-1 includes an illumination optical system 110, a reflected illumination optical system 120, an object system 130, an imaging optical system 140, a sensor system 150, an arithmetic circuit unit 160, A storage device 181.
The illumination optical system 110 includes a light source 111, a slit plate 112, and an objective lens 113. The reflective illumination optical system 120 includes a polarization beam splitter 121, a λ / 4 plate 122, a transflective plate 123, and an objective lens 124.
The object system 130 has a laser displacement meter 132 that measures the displacement of the patterned object surface.
Note that the pattern inspection target surface 131 includes an exposure mask used for manufacturing a semiconductor device, for example.
The imaging optical system 140 has an imaging lens 141.
The sensor system 150 includes an image sensor 151, a displacement measurement sensor mirror 152, and a displacement measurement sensor 153.
The arithmetic circuit unit includes an arithmetic circuit 161, a reference image generation circuit 162, a comparison circuit 163, and a storage device 181, which are connected to each other by a bus (not shown). Examples of the storage device 181 include a magnetic disk device and a memory.
As shown in FIG. 2, the slit plate 112 includes a first opening (reference pattern slit) 112-A serving as a displacement measurement slit and a second opening (object surface slit) serving as a slit opened for imaging. ) 112-B. The first opening 112-A is opened in a cross shape, for example, and the second opening 112-B is opened in a rectangle, for example. The optical path (broken line) of the light passing through the object surface slit 112-B and the optical path (two-dot long chain line) of the light passing through the reference pattern slit 112-A are almost the same, and separate sensors installed near each other. Is imaged.
Note that the displacement of the position of the object surface 131 is measured using a sensor such as a laser displacement meter 132 that measures the XY displacement of the stage on which the object is placed.

The transflective plate 123 is a plate (film) that has both reflection performance and transmission performance, reflects part of light, and transmits all or part of the remaining reflected light. As the transflective plate, for example, a single-sided uncoated quartz plate can be used. In addition to the single-side non-coated quartz plate, any plate that reflects part of the light and transmits the remaining (part) can be used in the same manner. In the first embodiment, a reflectance of 8%, for example, is used. However, the present invention is not limited to this, and the reflectance is 1% or more and 99% or less depending on the sensitivity of the displacement sensor and the imaging sensor. It is also preferable to use a transflective plate having a rate in the range of 99% to 1%.
Further, instead of the polarizing beam splitter 121 and the λ / 4 plate 122, a non-polarizing beam splitter may be used.

First, the optical path (two-dot long chain line) of the reference pattern (first image) will be described.
In the illumination optical system 110, the illumination light from the light source 111 that has passed through the first opening 112-A passes through the objective lens 113. Then, in the reflective illumination optical system 120, the light is reflected by the polarization beam splitter 121 with an inclination, passes through the λ / 4 plate 122, and a part of the illumination light is reflected by the semi-transmissive reflective plate 123, and again, the reflected illumination optical system. 120 passes through the λ / 4 plate 122 and passes through the polarization beam splitter 121. Next, an image is formed as a first image by the imaging lens 141 of the imaging optical system 140. Of the illumination light, part of the illumination light reflected by the transflective reflector 123 includes light that has passed through the second opening 112-B, but passes through the first opening 112-A. Only the emitted light (first partial image) is imaged on the displacement measuring sensor 153. At this time, the first partial image is reflected on the displacement measurement sensor mirror 152 having an inclination, and at least the first partial image is shifted to form the first partial image on the displacement measurement sensor 153. The position of the displacement measuring sensor 153 is adjusted to a position where the light of the pattern image on the object surface 131 is not incident.
Here, since the light beam is collimated at the position of the transflective plate, the light reflected at such a position can be imaged by the imaging optical system 140. The image can be shifted so that the first image formed by the reflected light of the transflective reflector does not appear in the imaging sensor.
In order to make the optical path of the reference pattern substantially the same as the optical path of the object, it is preferable that the imaging sensor 151, the displacement measurement sensor mirror 152, and the displacement measurement sensor 153 are installed in the vicinity.

Next, the optical path (broken line) of the object pattern (second image) will be described.
In the illumination optical system 110, the illumination light of the light source 111 that has passed through the second opening (target surface slit) 112 -B passes through the objective lens 113. Then, in the reflective illumination optical system 120, it is reflected with an inclination by the polarization beam splitter 121, passes through the λ / 4 plate 122, a part of the illumination light is reflected by the transflective plate 123, and the remaining illumination light (illumination) The remainder of the light passes through the transflective reflector 123 and further passes through the objective lens 124. As the objective lens 124, for example, an infinity correction type lens can be used. In the object system 130, the illumination light that has passed through the objective lens 124 irradiates the object surface 131. The illumination light (second image) reflected from the object surface 131 again passes through the objective lens 124, the transflective plate 123, and the λ / 4 plate 122 of the reflective illumination optical system 120, and passes through the polarization beam splitter 121. pass. Next, the second image is formed on the imaging sensor surface by the imaging lens 141 of the imaging optical system 140. The imaging sensor 151 is arranged at a position where a region on the mask illuminated by the second opening can be acquired, and only the second partial image that has passed through the second opening in the second image is picked up by the imaging sensor 151. To form an image.

  FIG. 3 is a virtual diagram when it is assumed that the first image reflected by the transflective reflector 123 and the second image reflected by the object 131 are formed on the same plane. Each image is formed at each imaging point on the virtual plane of FIG. 3, and the closer the optical path of the reference pattern and the object is, the closer the interval between the images is. It is preferable to place the visual field of the displacement measuring sensor 153 and the visual field of the imaging sensor 151 as close as possible because the influence of fluctuation can be made the same. However, there is a problem of reflection of an image outside the imaging target on the sensor due to the physical constraints of the sensor and the proximity of the reference pattern and the optical path of the object. For this purpose, a displacement measurement sensor mirror 152 that reflects at least the displacement measurement sensor visual field region is provided immediately before the image formation point, and the reflected light is measured by the displacement measurement sensor. The first partial image is shifted to a desired position by adjusting the angle of the transflective plate. In addition, if the reflection by the displacement measurement sensor mirror 152 and the imaging by the displacement measurement sensor 153 can measure the influence of fluctuation in the optical path from the imaging of the reference pattern, the displacement measurement sensor mirror 152 and the displacement measurement sensor 153 are Also in this embodiment, it may be other than the above configuration.

  In the imaging optical system 140, the light beam of the reference pattern (two-dot long chain line) forms an image on the sensor 151 through almost the same optical path as the light beam (broken line) of the inspection object. For this reason, even if air fluctuations occur in the optical path of the imaging optical system 140 having a long optical path length, the light beam from the inspection object surface 131 (broken line) and the light beam from the reference pattern (two-dot long chain line) are almost Due to the same influence, the displacement measurement of the image (second partial image) of the object surface 131 can be performed by the displacement generated in the image (first partial image) measured by the displacement measurement sensor 153.

  As the reference image generation step, the reference image generation circuit 162 first reads design data for each predetermined area, for example, from a magnetic disk device (storage device 181), and designs the object to be the read sample to be inspected. Data is converted (development processing) into developed image data that is binary or multivalued image data. The predetermined region may be an image region (area) to be compared with the optical image. For example, an area (area) of 1024 × 1024 pixels is assumed.

  The figure that constitutes the pattern defined in the design data is a basic figure such as a rectangle or triangle. For example, the coordinates (x, y) at the reference position of the figure, the length of the side, and the figure type such as the rectangle or triangle Graphic data defining the shape, size, position, etc. of each pattern graphic is stored with information such as a graphic code serving as a distinguishing identifier.

Such graphic data is expanded to data for each graphic, and a graphic code indicating a graphic shape of the graphic data, a graphic dimension, and the like are interpreted. Then, binary or multivalued image data is developed as a pattern arranged in a grid having a grid with a predetermined quantization size as a unit. The developed image data (developed image data) is stored in a pattern memory (not shown) or a magnetic disk device in the circuit. In other words, in the occupancy rate calculation unit, the design pattern data is read, and the occupancy rate of the figure in the design pattern is calculated for each cell formed by virtually dividing the inspection area as a cell with a predetermined dimension as a unit, The n-bit occupation ratio data is output to the pattern memory or the magnetic disk device. For example, it is preferable to set one square as one pixel. If a resolution of 1/2 ⁸ (= 1/256) is given to one pixel, 1/256 small areas are allocated by the figure area arranged in the pixel, and the occupation ratio in the pixel is set. Calculate. The developed image data is stored in a pattern memory or a magnetic disk device as area-unit image data defined by 8-bit occupancy data for each pixel.

  Then, as an image processing step, the reference image generation circuit 162 inputs the developed image data, performs data processing (image processing) on the developed image data, and generates reference image data for comparison with the optical image data. . The reference image generation circuit 162 is an example of a reference image data generation unit. The reference image generation circuit 162 may perform appropriate filter processing on the developed image data.

  The output reference data (standard image data) is output to the comparison circuit 163. The reference data is, for example, 8-bit unsigned data for each pixel, and the brightness gradation of each pixel is expressed by, for example, 0 to 255.

Next, the measurement by the displacement measurement sensor 153 and the arithmetic circuit 161 will be described.
The configuration of the reference pattern and the displacement measurement sensor is shown in FIG. In this configuration, as shown in the schematic diagram of FIG. 4A, the first opening 112-A has a cross shape, for example. In addition to the cross, the reference pattern may be any shape that can measure X and Y displacement. The pattern image of this image is introduced into the displacement measuring sensor 153 via the optical path (two-dot long chain line) described above. As shown in FIG. 4B, the displacement measuring sensor 153 is, for example, a four-divided sensor, and is arranged so that the center of the cross of the reference pattern comes to the center of the division. FIG. 4C is an image diagram in which the first opening 112-A is imaged on the displacement measurement sensor 153 when there is no displacement due to air fluctuation. In the quadrant sensor, the intensity of light incident on the four regions can be measured independently, and the output of each is A (153-A), B (153-B), C (153-C), D (153). -D), for example, the cross image X displacement and Y displacement when formed on the displacement measuring sensor 144 as shown in FIG. 4D can be calculated by the following calculation in the arithmetic circuit system.
X = {(A + B)-(B + C)} / (A + B + C + D)
Y = {(A + C)-(B + D)} / (A + B + C + D)

Further, the configuration of the first opening 112-A and the displacement measurement sensor 153 is not limited to this, and the configuration shown in FIG. In this configuration, as shown in FIG. 5A, a plurality of slits are formed as the first opening 112-A, and there are two for X displacement measurement and two for Y displacement measurement. The slit for measuring X displacement is a rectangle that is long in the X direction (left and right in the figure) and is formed by shifting the position in the Y direction. The slit for measuring Y displacement is a rectangle that is long in the Y direction (vertical direction in the figure), and is formed by shifting the position in the X direction. Such a pattern image is introduced into the displacement measurement sensor. Regarding the displacement measurement sensor 153, a displacement measurement sensor slit plate having a plurality of openings 153-F and 153-G as shown in FIG. It is further provided that 153-E is arranged on the front side of the image formed on the quadrant sensor itself. In the case of having the displacement measurement sensor slit plate 153 -E, when overlapping as shown in FIG. 5C, only the pattern that has passed through the displacement measurement sensor slit plate 153 -E of the first opening 112 -A. The image is formed on the displacement measuring sensor 153 as shown in FIG. The displacement (X, Y) can be calculated from the following formula, for example, from the ratio of increase / decrease of the light passing through the openings 153 -F and 153 -G and imaged on the displacement measurement sensor 153.
X = (A−B) / (A + B)
Y = (C−D) / (C + D)
The configuration of the reference pattern and the displacement measurement sensor (slit plate) is not particularly limited as long as the displacement of X and Y can be obtained as described above. When it is desired to know the influence of fluctuation of only one of X and Y, the number of sensors, the reference pattern shape, the arithmetic circuit unit, etc. may be adjusted to measure either displacement.

  On the other hand, the measurement data (optical image data) output from the image sensor 151 and the calculated displacement amount (X, Y) are sent to the comparison circuit 163 together with the data of the laser displacement meter 132 indicating the position of the object on the stage. Is output. The measurement data is, for example, 8-bit unsigned data for each pixel, and the brightness gradation of each pixel is expressed by, for example, 0 to 255.

  Then, as a comparison step, the comparison circuit 163 compares the optical image data of the corresponding predetermined region with the reference image data for each pixel under a predetermined determination condition. Hereinafter, the processing in the comparison circuit 163 will be specifically described. In the comparison circuit 163, first, optical image data for one stripe is input, and the optical image data for one stripe is cut out with the same area size as the reference image. In this case, it goes without saying that the area to be cut out is matched with the area for generating the reference image. The optical image data in which the region sizes are matched is stored in a memory (not shown) in the comparison circuit 163. On the other hand, the generated reference image data of the predetermined area is also stored in another memory (not shown) in the comparison circuit 163. Then, the position of the optical image data is corrected using the displacement amount of the laser displacement meter and the displacement amount of the reference pattern. This position correction is performed in units of sub-pixels by interpolation processing. As a result, inspection without the influence of image fluctuation can be performed. Then, the aligned optical image data and reference image data are compared for each pixel according to the determination condition, and the presence or absence of a defect is determined. As the determination condition, for example, the threshold value Qm when comparing the two for each pixel according to a predetermined algorithm and determining the presence or absence of a defect corresponds. Alternatively, for example, a comparison algorithm for comparing the two and determining the presence or absence of a defect is applicable.

  Then, the compared result is output to the storage device 181 and stored, for example. The storage device may be further connected to a monitor, and the result may be output to the monitor, or the result may be output by a printer. Examples of the storage device include a magnetic disk device, a magnetic tape device, and an FD.

(Embodiment 2)
In the second embodiment, the optical system is further provided with an image displacement correction unit to perform displacement correction (image displacement correction) of an image captured in real time.
This displacement correction method will be described using a pattern inspection apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 100-2 in FIG. 6 as an example. The pattern inspection apparatus according to the second embodiment is the same as that shown in FIG. 1 except that a movable mechanism 171 and a correction circuit 173 are added. The movable mechanism 171 moves the imaging lens 141 in the XY plane based on a control signal from the correction circuit 173 to correct the image displacement in real time. The correction circuit 173 drives the imaging lens 141 so that the displacement of the first image in the displacement meter side sensor 153 becomes zero (or a desired range). For example, the acquired image can be stabilized by controlling the movable mechanism 171 by servo control. In this method, it is preferable that blurring can be reduced by correcting the displacement generated within the exposure time at a high speed, and that errors generated in the correction of the image can be corrected immediately. In FIG. 6, the imaging lens 141 is moved as an example, but the same effect can be obtained by driving the imaging sensor 151 by controlling the movable mechanism 172. In addition to this, the same effect can be obtained by tilting the parallel plane plate for image displacement.
In the case of this configuration, the amount of displacement of the first partial image can be calculated by the arithmetic circuit unit 160 similar to that of Embodiment 1, and the results can be compared. Then, the result can be stored in the storage device 181 and further the result can be output to a monitor or a printer.
In addition, the point which adjusts the angle of the transflective plate 123 is the same as that of the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.

(Embodiment 3)
In the third embodiment, the single displacement measurement sensor is used in the first embodiment. However, by installing a plurality of displacement measurement sensors, it is possible to correct the magnification change. The pattern inspection apparatus 100-3 shown in FIG. In the third embodiment, in order to reflect light from the reference pattern at different angles, a total of two parts of the first transflective plate 123a and the second transflective plate 123b are installed at different angles, respectively. A total of two displacement measurement sensors (153a, 153b) for imaging the reference pattern reflected by the respective transflective reflectors, and a total of two displacement measurement sensor mirrors (152a, 152b) for applying light to the sensors. It is the same as that of FIG. 1 except using. In FIG. 7, the optical path of the reference pattern is indicated by a one-point long chain line and a two-point long chain line. The optical path indicated by the two-dot long chain line is the same as that described in Embodiment 1, and is reflected by the displacement measurement sensor mirror 152a, and the first partial image is formed by the displacement measurement sensor 153a. The optical path of the one-point long chain line reference pattern is the second half-chain line optical path of the two-point long chain line of the illumination light transmitted through the first semi-transmissive reflector 123a on the imaging optical system 140 side. Illumination light reflected by the transmissive reflecting plate 123b. The illumination light reflected by the second transflective reflector 123b is imaged as a third image by the imaging lens 141.
Then, similarly to the first partial image, at least the third partial image that is the portion that has passed through the first opening in the third image is reflected by the displacement measurement sensor mirror 152b and is detected by the displacement measurement sensor 153b. Imaged. Since the optical path of the reference pattern reflected by the second transflective reflector also passes through substantially the same optical path of the object, the displacement measurement sensor mirror 152b, which is a reflector, and the displacement measurement sensor 153b that forms an image are also included in the imaging sensor 142. It is installed in the vicinity. For example, these sensors are arranged so that the reflected image sandwiches the image sensor on the image sensor surface.

  FIG. 8 is a virtual diagram on the assumption that the first and third images reflected by the transflective reflectors 123a and 123b and the second image reflected by the object 131 are formed on the same plane. It is. Each image is formed at each imaging point on the virtual plane in FIG. 8, and the closer the optical path between the reference pattern and the object, the closer the sensor interval between the images. It is preferable that the visual fields of the displacement measuring sensors 153a and 153b and the visual field of the image sensor 151 be as close as possible because the influence of fluctuation can be made the same. However, there is a problem of reflection of an image outside the imaging target on the sensor due to the physical constraints of the sensor and the proximity of the reference pattern and the optical path of the object. For this purpose, the displacement measurement sensor mirrors 152a and 152b that reflect at least the displacement measurement sensor visual field region are installed immediately before the image formation point, and the reflected light is measured by the displacement measurement sensors 153a and 153b. The first and third partial images are shifted and adjusted to desired positions by adjusting the angles of the transflective plates 123a and 123b.

In the case of the configuration of the pattern inspection apparatus in FIG. 7, the arithmetic circuit 161 can calculate the displacement amount and the magnification change value by the following calculation formula, for example.
X displacement amount = (X1 + X2) / 2
Y displacement = (Y1 + Y2) / 2
X magnification change value = (X1-X2) / Lx
Y magnification change value = (Y1-Y2) / Ly
Lx and Ly are distances between the displacement measuring sensors.
In addition, the point which adjusts the angle of the 1st transflective plate 123a and the 2nd transflective plate 123b is the same as the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.

With the configuration of the pattern inspection apparatus shown in FIG. 7, it is possible to obtain information on the change in magnification due to air fluctuation, and to obtain and correct more detailed information on air fluctuation.
In Embodiment 3, two parts each of the transflective plate, the displacement measurement sensor mirror, and the displacement measurement sensor are used, but more than two parts may be installed. In addition, since the light quantity of the reference pattern to be reflected or the light quantity reaching the object decreases as the number of the transflective plates increases, it is preferable to increase the transmissivity of the transflective plate, for example, when many are installed.
Then, the position value and magnification of the acquired optical image are corrected using the displacement amount (X, Y) and the magnification change value (X, Y). Specifically, if the displacement amount (X, Y) is added to the position of the optical image, and the magnification of the image is multiplied by the reciprocal of the magnification change value (X, Y) in each of the X and Y directions. Good. Then, the corrected optical image and the reference image may be aligned.
In the case of this configuration, the amount of displacement of the first partial image can be calculated by the arithmetic circuit unit 160 similar to that of Embodiment 1, and the results can be compared. Then, the result can be stored in the storage device 181 and further the result can be output to a monitor or a printer.
The pattern inspection apparatus having the schematic configuration of the pattern inspection apparatus 100-4 in FIG. 9 is a diagram except that the imaging lens 141 and the image sensor 151 are provided with movable mechanisms 171 and 172 and a correction circuit 173. 7 is the same. In the apparatus having the configuration as shown in FIG. 9, the X and Y magnification change values are further multiplied by 1 (or desired values) so that the displacement amount becomes 0 (or a desired range) as in the second embodiment. Thus, the correction circuit 173 performs the calculation, and the movable mechanisms 172 and 173 are controlled by servo control, for example, and the image displacement correction and the image magnification correction are performed together to stabilize the acquired image.

(Embodiment 4)
The fourth embodiment has a configuration as shown in the schematic diagram of the pattern inspection apparatus 200-1 in FIG. The pattern inspection apparatus according to the fourth embodiment is different from FIG. 1 in that the reference numerals of the 100th order in FIG. 1 are the 200th order, and the positions of the objective lens 224, the object surface 231 and the laser displacement meter 232 are different. The objective lens 224 and the object surface 231 are installed in a direction in which the illumination light from the light source 211 passes through the polarization beam splitter 221, and the λ / 4 plate 222 b different from the λ / 4 plate 222 a is used as the object surface. It is the same as that of FIG. 1 except that it is further provided on the 231 side, and that the plate that reflects the light of the reference pattern is not the transflective plate but the reflecting plate 223.
The illumination light that has passed through the first opening 212-A (reference pattern) and reflected by the polarization beam splitter 221 passes through the first λ / 4 plate 222a, and is ideally totally reflected. The light is reflected by the reflecting plate 223 and passes through the first λ / 4 plate 222a again. Then, the light that has passed through the first λ / 4 plate 222 a again passes through the polarization beam splitter 221, and at least a first partial image is formed on the displacement measurement sensor 253 as in the first embodiment. . The illumination light that has passed through the second opening 212-B (object surface) and passed through the polarization beam splitter 221 passes through the second λ / 4 plate 222b, passes through the objective lens 224, and passes through the object 231. Irradiate. The reflected light reflected by irradiating the pattern of the object surface 231 passes through the objective lens 224 and the λ / 4 plate 222b. Then, the light is reflected by the polarization beam splitter 221 and only the second partial image is formed on the image sensor 251 as in the first embodiment. Except for the above, the apparatus has the same configuration as that of the first embodiment.
In the case of this configuration, the amount of displacement of the first partial image can be calculated by the arithmetic circuit unit 260 similar to that of Embodiment 1, and the results can be compared. Then, the result can be stored in the storage device 281 and further the result can be output to a monitor or a printer.
In addition, the point which adjusts the angle of the reflecting plate 223 is the same as that of the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.
The pattern inspection apparatus having the configuration of the pattern inspection apparatus 200-2 in FIG. 11 is a diagram except that the imaging lens 241 and the image sensor 251 are provided with movable mechanisms 271 and 272 and a correction circuit 273. 10 is the same. The apparatus having the configuration as shown in FIG. 11 can further perform image displacement correction similar to that of the second embodiment.

(Embodiment 5)
In the fifth embodiment, a pattern inspection apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 200-3 in FIG. 12 will be described. Using a semi-transmissive reflector 223a and a reflector 223b that reflect the reference pattern, the angles of these (semi-transmissive) reflectors are different, and a total of two displacement measurement sensor mirrors (252a, 252b) and a total of two displacement measurements It is the same as that of FIG. 10 except using a sensor (253a, 253b).
In FIG. 12, the optical path of the reference pattern is indicated by a one-point long chain line and a two-point long chain line. The optical path indicated by the two-dot long chain line is the same as that described in the fourth embodiment. Of the illumination light, the illumination light reflected by the transflective plate 223a is reflected by the first displacement measurement sensor mirror 252a. A first partial image is formed by the first displacement measuring sensor 253a. The optical path of the one-point long chain line reference pattern is the optical path of the illumination light reflected by the reflection plate 223b on the object system 230 side out of the illumination light that has passed through the semi-transmissive reflection plate 223a on the imaging optical system 240 side. The illumination light reflected by the reflecting plate 223b is imaged as a third image in the imaging optical system 240. As in the third embodiment, at least a third partial image of the third image that has passed through the first opening 212-A is reflected by the second displacement measurement sensor mirror 252b. An image is formed by the second displacement measurement sensor 253b.
In the case of this configuration, the arithmetic circuit unit 260 similar to that in Embodiment 3 calculates the displacement amounts of the first and third partial images and the magnification change value of the second partial image, and compares the results. it can. Then, the result can be stored in the storage device 281 and the result can be output to a monitor or a printer.
In addition, the point which adjusts the angle of the semi-transmissive reflective plate 223a and the reflective plate 223b is the same as the case where the angle of the semi-transmissive reflective plate 123 in Embodiment 1 is adjusted.
The pattern inspection apparatus having the schematic configuration of the pattern inspection apparatus 200-4 in FIG. 13 is a diagram except that the imaging lens 241 and the image sensor 251 are provided with movable mechanisms 271 and 272 and a correction circuit 273. 12 is the same. The apparatus having the configuration as shown in FIG. 13 can further perform image displacement correction and image magnification correction similar to those of the third embodiment.
The (semi-transmissive) reflector, the displacement measurement sensor mirror, and the displacement measurement sensor may have more than two parts.

(Embodiment 6)
The sixth embodiment has a configuration as shown in the schematic diagram of the pattern inspection apparatus 300-1 in FIG. In the pattern inspection apparatus according to the sixth embodiment, the number of the code in the 100th order in FIG. 1 is the 300th order, there is no transflective plate, and the illumination light from the light source 311 passes through the polarization beam splitter 321. 1 except that a λ / 4 plate 322b and a reflecting plate 323 are installed in the passing direction.
The illumination light that has passed through the second opening 312 -B (object surface) and reflected by the polarization beam splitter 321 passes through the first λ / 4 plate 322 a, passes through the objective lens 324, and passes through the object. 331 is irradiated. The reflected light reflected by irradiating the pattern of the object surface 331 passes through the objective lens 324 and the λ / 4 plate 322b, is reflected by the polarization beam splitter 221, and is the second partial image as in the first embodiment. Only the image is formed on the image sensor 351. The illumination light that has passed through the first opening 312-A (reference pattern) and passed through the polarization beam splitter 321 passes through the second λ / 4 plate 322b, and ideally instead of the transflective plate. The light is reflected by the reflection plate 323 that totally reflects, and passes through the second λ / 4 plate 322a again. The light that has passed through the second λ / 4 plate 322 a again is reflected by the polarization beam splitter 321, and a first partial image is formed on the displacement measurement sensor 353 as in the first embodiment. Except for the above, the apparatus has the same configuration as that of the first embodiment.
In the case of this configuration, the amount of displacement of the first partial image can be calculated by the arithmetic circuit unit 360 similar to that of Embodiment 1, and the results can be compared. Then, the result can be stored in the storage device 381, and the result can be output to a monitor or a printer.
In addition, the point which adjusts the angle of the reflecting plate 323 is the same as the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.
The pattern inspection apparatus having the schematic configuration of the pattern inspection apparatus 300-2 in FIG. 15 is a diagram except that the imaging lens 341 and the image sensor 351 are provided with movable mechanisms 371 and 372 and a correction circuit 373. 14 is the same. The apparatus having the configuration as shown in FIG. 15 can further perform image displacement correction similar to that in the second embodiment.

(Embodiment 7)
In the seventh embodiment, a pattern inspection apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 300-3 in FIG. 16 will be described. The pattern inspection apparatus according to the seventh embodiment uses a transflective reflector 323a and a reflector 323b that reflect a reference pattern. The (transflective) reflectors have different angles, and a total of two displacement measurement sensor mirrors ( 352a, 352b) and a total of two displacement measurement sensors (353a, 353b) are used, as in FIG.
In FIG. 16, the optical path of the reference pattern is indicated by a one-point long chain line and a two-point long chain line. The optical path indicated by the two-dot long chain line is the same as that described in the sixth embodiment. Of the illumination light, the illumination light reflected by the transflective reflector 323a is reflected by the first displacement measurement sensor mirror 343a. The first partial image is formed by the first displacement measuring sensor 344a. The optical path of the one-point long chain line reference pattern is the illumination of the two-point long chain line that is reflected by the reflecting plate 323b on the object system 330 side out of the light transmitted through the semi-transmissive reflecting plate 323a on the imaging optical system 340 side. It is the optical path of light. The illumination light reflected by the reflecting plate 323b is imaged as a third image in the imaging optical system 340. As in the third embodiment, at least a third partial image of the third image that has passed through the first opening 312-A is reflected by the second displacement measurement sensor mirror 343b. An image is formed by the second displacement measuring sensor 344b.
In FIG. 16, the second partial image of the optical path of the object pattern is picked up by the image sensor 351 as in the first embodiment.
In the case of this configuration, the arithmetic circuit unit 360 similar to that of Embodiment 3 calculates the displacement amounts of the first and third partial images and the magnification change value of the second partial image, and compares the results. it can. Then, the result can be stored in the storage device 381, and the result can be output to a monitor or a printer.
In the case of this configuration, the arithmetic circuit unit 360 similar to that of Embodiment 3 calculates the displacement amounts of the first and third partial images and the magnification change value of the second partial image, and further outputs the calculation result. It becomes possible to do.
In addition, the point which adjusts the angle of the transflective plate 323a and the reflective plate 323b is the same as the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.
Note that the pattern inspection apparatus having the schematic configuration of the pattern inspection apparatus 300-4 in FIG. 17 is a diagram except that the imaging lens 341 and the image sensor 351 are provided with movable mechanisms 371 and 372 and a correction circuit 373. This is the same as 16. The apparatus configured as shown in FIG. 17 can perform image displacement correction and image magnification correction similar to those of the third embodiment.
The (semi-transmissive) reflector, the displacement measurement sensor mirror, and the displacement measurement sensor may have more than two parts.

(Embodiment 8)
In the eighth embodiment, a pattern inspection apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 400-1 in FIG. 18 will be described. In the pattern inspection apparatus according to the eighth embodiment, the reference numerals in FIG. 1 are from the 100s to the 400s, the λ / 4 plate 422, the transflective plate 423, the objective lens 424, and the object. The arrangement of the surface 431 and the laser displacement meter 432 is different from that in FIG. 1, and the λ / 4 plate 422, the transflective plate 423, and the objective lens 424 in the direction in which the illumination light from the light source 411 passes through the polarization beam splitter 421. 1 except that an object surface 431 is provided.
In FIG. 18, in the optical path of the eighth embodiment, the illumination light that has passed through the first and second openings 412-A and B passes through the polarization beam splitter 421, and the first transflective plate 423a and the first The light path is the same as that of the first embodiment except that the illumination light reflected by the second transflective plate 423b and the object surface 431 is reflected by the polarization beam splitter 421 and introduced into the imaging optical system 440. . Then, as in the first embodiment, the first partial image is formed on the displacement measurement sensor 453 and the second partial image is picked up by the image sensor 451.
In the case of this configuration, the amount of displacement of the first partial image can be calculated by the arithmetic circuit unit 460 similar to that of Embodiment 1, and the results can be compared. Then, the result can be stored in the storage device 481, and the result can be output to a monitor or a printer.
In addition, the point which adjusts the angle of the 1st transflective plate 423a and the 2nd transflective plate 423b is the same as that of the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.
The pattern inspection apparatus having the schematic configuration of the pattern inspection apparatus 400-2 of FIG. 19 is a diagram except that the imaging lens 441 and the image sensor 451 are provided with movable mechanisms 471 and 472 and a correction circuit 473. 18 is the same. The apparatus having the configuration as shown in FIG. 19 can further perform image displacement correction similar to that of the second embodiment.

(Embodiment 9)
In the ninth embodiment, a pattern inspection apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 400-3 in FIG. 20 will be described. The pattern inspection apparatus according to the ninth embodiment uses a total of two first and second transflective plates (423a, 423b) that reflect the reference pattern, and that the angles of these transflective plates are different. Except for using two parts of displacement measurement sensor mirrors (452a, 452b) and two parts of displacement measurement sensors (453a, 453b), it is the same as FIG.
In FIG. 20, the optical path of the reference pattern is indicated by a one-point long chain line and a two-point long chain line. The optical path indicated by the two-dot long chain line is the same as that described in Embodiment 8, and the illumination light reflected by the first transflective plate in the illumination light is reflected by the first displacement measurement sensor mirror 452a. Reflected and a first partial image is formed by the first displacement measuring sensor 453a. The optical path of the one-point long chain line reference pattern is the second half-chain line optical path of the illumination light that has passed through the first semi-transmissive reflector 423a on the imaging optical system 440 side. It is the optical path of the illumination light reflected by the transmissive reflection plate 423b. The illumination light reflected by the second transflective reflector 423b is imaged as a third image in the imaging optical system 440. Then, as in the third embodiment, the third partial image of the third image that has passed through the first opening 412 -A is reflected by the second displacement measurement sensor mirror 443b, and the displacement measurement sensor. An image is formed at 444b.
In the case of this configuration, the arithmetic circuit unit 460 similar to that of Embodiment 3 calculates the displacement amounts of the first and third partial images and the magnification change value of the second partial image, and compares the results. it can. Then, the result can be stored in the storage device 481, and the result can be output to a monitor or a printer.
In the case of this configuration, the arithmetic circuit unit 460 similar to that in Embodiment 3 calculates the displacement amounts of the first and third partial images and the magnification change value of the second partial image, and further outputs the calculation result. It becomes possible to do.
In addition, the point which adjusts the angle of the 1st transflective plate 423a and the 2nd transflective plate 423b is the same as that of the case where the angle of the transflective plate 123 in Embodiment 1 is adjusted.
The imaging lens 441 and the image sensor 451 are provided with tilt or shift mechanisms 471 and 472 and a correction circuit 473 so that the image forming lens 441 and the image sensor 451 can be implemented using an apparatus having a configuration as shown in the schematic diagram of the pattern inspection apparatus 400-4 in FIG. The same image displacement correction and image magnification correction as those in the third embodiment can be further performed.
The transflective plate, the displacement measurement sensor mirror, and the displacement measurement sensor may have more than two parts.

In the above description, what is described as “to part”, “to circuit”, or “to process” can be configured by a computer-operable program. Or you may make it implement by not only the program used as software but the combination of hardware and software. Alternatively, a combination with firmware may be used. When configured by a program, the program is stored in a storage medium such as a magnetic disk device, a magnetic tape device, an FD, or a ROM (Read Only Memory). For example, the arithmetic circuit, the reference image generation circuit, the comparison circuit, and the like that constitute the arithmetic control unit may be configured by an electric circuit or may be realized as software that can be processed by a control computer. Moreover, you may implement | achieve with the combination of an electrical circuit and software.
In addition, the arithmetic circuit, the reference image generation circuit, the comparison circuit, the correction circuit, and the like may be connected to a storage device, a monitor, a printer, and the like by wiring not shown.

The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.
For example, the present invention can be applied not only to the above-described Die to Database inspection but also to alignment when performing a Die to Die inspection.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used.

  In addition, all pattern inspection apparatuses or pattern inspection methods that include the elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Pattern inspection apparatus 110 ... Illumination optical system 111 ... Light source 112 ... Illumination slit 112-A ... 1st opening part (reference | standard pattern)
112-B ... 2nd opening part (object surface)
DESCRIPTION OF SYMBOLS 113 ... Objective lens 120 ... Reflective illumination optical system 121 ... Polarization beam splitter 122 ... (lambda) / 4 board 123 ... Semi-transmissive reflector (123a: 1st semi-transmissive reflector, 123b: 2nd semi-transmissive reflector)
DESCRIPTION OF SYMBOLS 124 ... Objective lens 130 ... Object system 131 ... Object surface 132 ... Laser displacement meter 140 ... Imaging optical system 141 ... Imaging lens 151 ... Imaging sensor 152 ... Displacement measurement sensor mirror (152a: 1st displacement measurement sensor mirror) , 152b: second displacement measuring sensor mirror)
153 ... Displacement measurement sensor (153a: first displacement measurement sensor, 153b: second displacement measurement sensor)
Reference Signs List 161 ... arithmetic circuit 162 ... reference image generation circuit 163 ... comparison circuit 171 ... objective lens moving mechanism 172 ... imaging sensor moving mechanism 173 ... correction circuit 181 ... storage device 222a ... first λ / 4 plate 222b ... second λ / 4 plates 223 ... reflecting plate (223a: transflective plate, 223b: reflecting plate)
322a: first λ / 4 plate 322b: second λ / 4 plate 323: reflector (323a: transflective plate, 323b: reflector)
Refer to the embodiment for the description of the not-described symbols.

Claims (9)

A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
A transflective reflector that reflects a portion of the illumination light and passes the remainder of the illumination light to the patterned object surface;
An imaging optical system that forms an image of the first image reflected by the transflective plate and the second image reflected by the object surface;
A displacement measuring sensor for measuring a displacement of a first partial image passing through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first partial image;
A comparison circuit that compares the optical image with the reference image using a displacement amount of the position of the first partial image;
A pattern inspection apparatus comprising: A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
A beam splitter for branching the illumination light by passing and reflecting;
A reflector that reflects a portion of the illumination light reflected by the beam splitter;
An imaging optical system that forms a first image reflected by the reflecting plate and a second image formed by the remainder of the illumination light that passes through the beam splitter and is reflected by the patterned object surface When,
A displacement measuring sensor for measuring a displacement of a first partial image passing through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first partial image;
A comparison circuit that compares the optical image with the reference image using a displacement amount of the position of the first partial image;
A pattern inspection apparatus comprising: A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
A beam splitter for branching the illumination light by passing and reflecting;
A reflector that reflects a portion of the illumination light that has passed through the beam splitter;
An imaging optical system that forms a first image reflected by the reflecting plate and a second image formed by the remainder of the illumination light reflected by the beam splitter and reflected by the patterned object surface When,
A displacement measuring sensor for measuring a displacement of a first partial image passing through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first partial image measured by the displacement measurement sensor;
A comparison circuit that compares the optical image with the reference image using a displacement amount of the position of the first partial image;
A pattern inspection apparatus comprising: A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
First and second transflective reflectors that reflect part of the illumination light and pass the remainder of the illumination light to the patterned object surface side;
A first image reflected by the first transflective plate, a second image reflected by the object surface, and a third image reflected by the second transflective plate. An imaging optical system for imaging;
A first displacement measuring sensor for measuring a displacement of a first partial image that has passed through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A second displacement measuring sensor for measuring a third partial image that has passed through the first opening in the displacement of the third image;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first and third partial images and a magnification change value of the second partial image;
A comparison circuit that compares the optical image with the reference image using the displacement amount and the magnification change value;
A pattern inspection apparatus comprising: A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
A beam splitter for branching the illumination light by passing and reflecting;
A transflective reflector that reflects a portion of the portion of the illumination light reflected by the beam splitter and passes the remainder of the portion of the illumination light;
A reflector that reflects the remainder of the illumination light that has passed through the transflective reflector;
A first image reflected by the transflective reflector, a second image by the remainder of the illumination light that has passed through the beam splitter and reflected by the patterned object surface, and reflected by the reflector An imaging optical system for forming the third image formed;
A first displacement measuring sensor for measuring a displacement of a first partial image that has passed through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A second displacement measuring sensor for measuring a displacement of a third partial image passing through the first opening in the third image;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first and third partial images and a magnification change value of the second partial image;
A comparison circuit that compares the optical image with the reference image using the displacement amount and the magnification change value;
A pattern inspection apparatus comprising: A slit plate in which first and second openings are formed;
An illumination optical system for illuminating illumination light through the slit plate;
A beam splitter for branching the illumination light by passing and reflecting;
A transflective plate that reflects a part of the part of the illumination light that has passed through the beam splitter and passes the remainder of the part of the illumination light;
A reflector that reflects the remainder of the part of the illumination light that has passed through the transflective reflector;
A first image reflected by the transflective plate, a second image by the remainder of the illumination light reflected by the beam splitter and reflected by the patterned object surface, and reflected by the reflector An imaging optical system for forming the third image formed;
A first displacement measuring sensor for measuring a displacement of a first partial image that has passed through the first opening in the first image;
An imaging sensor that captures a second partial image of the second image that has passed through the second opening;
A second displacement measuring sensor for measuring a displacement of a third partial image passing through the first opening in the third image;
A reference image generation circuit for generating a reference image for comparison with the optical image of the second partial image;
An arithmetic circuit for calculating a displacement amount of the position of the first and third partial images and a magnification change value of the second partial image;
A comparison circuit that compares the optical image with the reference image using the displacement amount and the magnification change value;
A pattern inspection apparatus comprising: At least one movable mechanism disposed in either or both of the imaging optical system and the imaging sensor;
A correction circuit for controlling the movable mechanism so as to correct the displacement amount of the position of the first partial image calculated by the arithmetic circuit;
The pattern inspection apparatus according to claim 1, further comprising: At least one movable mechanism disposed in either or both of the imaging optical system and the imaging sensor;
A correction circuit for controlling the movable mechanism so as to correct the displacement amount of the positions of the first and third partial images calculated by the arithmetic circuit;
The pattern inspection apparatus according to claim 4, further comprising: At least one movable mechanism disposed in either or both of the imaging optical system and the imaging sensor;
A correction circuit for controlling the movable mechanism so as to correct the displacement amount of the positions of the first and third partial images calculated by the arithmetic circuit;
The pattern inspection apparatus according to claim 4, further comprising: