JP2010145094A - Evaluation device and evaluation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evaluation device specifying a cause of an abnormality of a repeated pattern. <P>SOLUTION: In this evaluation device 1, a first imaging element 31 rotates an optical analyzer 21 so that the azimuth of a transmission axis of the optical analyzer 21 becomes equal to a tilt angle of 90°±3° with respect to a transmission axis of a polarizer 17, and a Fourier image is imaged in each condition, and an operation processing part 40 detects a state change of a repeated pattern 3 caused by a change of a dose amount based on a difference of signal intensity between two Fourier images, and detects a state change of the repeated pattern 3 caused by a focus change, based on an average of the signal intensity between the two Fourier images. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an evaluation apparatus and an evaluation method for evaluating a pattern formed on a surface of a semiconductor wafer, a liquid crystal substrate or the like.

Conventionally, various apparatuses for inspecting a pattern formed on the surface of a substrate such as a semiconductor wafer or a liquid crystal glass substrate have been proposed (see, for example, Patent Document 1). For example, when measuring the pattern width of a substrate with a scanning electron microscope (SEM), the measurement accuracy is high, but since the observation magnification is high and sampling is performed by sampling several points, the measurement takes an enormous amount of time. End up. Therefore, the light of a predetermined wavelength emitted from the light source is irradiated onto the surface of the test substrate by epi-illumination through the polarizer and the objective lens, and the reflected light from the test substrate by the illumination is converted into the objective lens and the polarizer. By detecting a Fourier image obtained through an analyzer that satisfies the conditions of crossed Nicols and a field stop with a CCD camera and selecting a place with high sensitivity in the Fourier image, the pattern width can be changed with high sensitivity. An inspection device for detection has been proposed.
JP 2006-135211 A

  However, in the method as described above, the pattern width can be detected, but the cause of the change in the pattern width cannot be specified.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide an evaluation apparatus and an evaluation method capable of specifying the cause of an abnormality of a repetitive pattern.

  In order to achieve such an object, the evaluation apparatus according to the present invention includes an illumination unit that irradiates a surface of a substrate having a predetermined repetitive pattern with linearly polarized light, and regular reflection light from the repetitive pattern irradiated with the linearly polarized light. An optical system that receives a polarization component having a vibration direction different from that of the linearly polarized light, a detection unit that detects the polarization component on a pupil plane of the optical system or a plane conjugate with the pupil plane, and a vibration direction of the linear polarization. A setting unit that sets an angle condition between the vibration direction of the polarization component, and an evaluation unit that evaluates the state of the repetitive pattern based on the polarization component detected by the detection unit. Detecting the polarization component obtained by setting the relationship between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set by the setting unit to a plurality of angle conditions, respectively. Parts are on the basis of the information of a plurality of the polarization component detected by the detection unit is adapted to evaluate the state of the repeated pattern.

  In the evaluation apparatus, the setting unit includes a vibration direction in a plane perpendicular to the traveling direction of the linearly polarized light and a vibration direction of the polarization component in a plane perpendicular to the traveling direction of the regular reflected light. The angle formed is preferably set so as to satisfy two angle conditions of 90 ° ± predetermined angle.

  Further, in the above-described evaluation apparatus, the repetitive pattern is formed using an exposure apparatus, and the detection unit includes a vibration direction of the linearly polarized light and a vibration direction of the polarization component set by the setting unit. Each of the polarization components obtained under two angle conditions in between, and the evaluation unit performs exposure in the exposure apparatus based on a difference in signal intensity corresponding to the two polarization components detected by the detection unit. Detecting a change in state of the repetitive pattern due to a change in amount, and determining a change in state of the repetitive pattern due to a change in focus in the exposure apparatus based on an average of signal intensities corresponding to the two polarization components. It is preferable to detect.

  In the evaluation apparatus described above, it is preferable that the illumination unit irradiates the surface of the substrate with the linearly polarized light by epi-illumination.

  Further, the evaluation method according to the present invention irradiates the surface of the substrate having a predetermined repetitive pattern with linearly polarized light, and among the regular reflected light from the repetitive pattern irradiated with the linearly polarized light, the linearly polarized light and the vibration direction Is a method for evaluating the state of the repetitive pattern by detecting the polarization component on a pupil plane of the received optical system or a plane conjugate with the pupil plane, A first step of setting an angle condition between a direction of vibration and the polarization direction of the polarization component, and a plurality of relationships between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set in the first step. A second step of setting the angle condition to irradiate the surface of the substrate with the linearly polarized light; and the repetitive pattern irradiated with the linearly polarized light under the plurality of angle conditions. A third step of receiving a polarized light component having a vibration direction different from that of the linearly polarized light from the specularly reflected light, and a pupil plane or a pupil plane of the optical system received in the third step under the plurality of angle conditions And a fourth step of detecting the polarization component in a plane conjugate with the second angle, and evaluating the state of the repetitive pattern based on information of the plurality of polarization components detected in the fourth step under the plurality of angle conditions, respectively. And a fifth step.

  In the evaluation method described above, in the first step, the vibration direction in a plane perpendicular to the traveling direction of the linearly polarized light, and the vibration direction of the polarization component in a plane perpendicular to the traveling direction of the regular reflection light. Is preferably set so as to satisfy two angle conditions of 90 ° ± predetermined angle.

  In the above evaluation method, the repetitive pattern is formed by using an exposure apparatus, and in the second step, the vibration direction of the linearly polarized light and the vibration of the polarization component set in the first step are used. In the third step, the surface of the substrate is irradiated with the linearly polarized light under two angle conditions, and in the third step, the positive pattern from the repetitive pattern irradiated with the linearly polarized light under the two angle conditions is irradiated. Of the reflected light, a polarization component having a vibration direction different from that of the linearly polarized light is received. In the fourth step, the pupil plane or the pupil plane of the optical system received in the third step under the two angle conditions. The polarization component in a conjugate plane is detected, and in the fifth step, a difference in signal intensity corresponding to the two polarization components detected in the fourth step, respectively. And detecting a change in the state of the repetitive pattern caused by a change in exposure amount in the exposure apparatus, and determining a change in focus in the exposure apparatus based on an average of signal intensities corresponding to the two polarization components. It is preferable to detect a change in the state of the repetitive pattern.

  In the evaluation method described above, in the second step, it is preferable to irradiate the surface of the substrate with the linearly polarized light by epi-illumination.

  According to the present invention, it is possible to identify the cause of a repetitive pattern abnormality.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the evaluation apparatus 1 of the present embodiment includes a wafer stage 5, an objective lens 6, a half mirror 7, an illumination optical system 10, a detection optical system 20, and first and second imaging elements. And the arithmetic processing unit 40. The semiconductor wafer 2 (hereinafter referred to as wafer 2) is transported from a wafer cassette (not shown) or a developing device by a transport system (not shown) after exposure and development of the uppermost resist film by an exposure device (not shown). Then, it is placed on the wafer stage 5 with the pattern (repetitive pattern) formation surface facing up.

  A plurality of chip areas are arranged vertically and horizontally on the surface of the wafer 2, and a predetermined repetitive pattern 3 is formed in each chip area (see FIG. 2). The repeated pattern 3 is a resist pattern (for example, a wiring pattern that is a line and space pattern) in which a plurality of line portions are arranged at a constant pitch along the short direction. The arrangement direction of the line portions is referred to as “repeating direction of the repeating pattern 3”.

  The wafer stage 5 is configured to be movable in three directions of X, Y, and Z axes (see FIG. 2) orthogonal to each other (note that the vertical direction in FIG. 2 is the Y axis direction, and the horizontal direction in FIG. Is the X-axis direction, and the direction perpendicular to the plane of FIG. 2 is the Z-axis direction). Thereby, the wafer stage 5 can support the wafer 2 so as to be movable in the X, Y, and Z axis directions. Further, the wafer stage 5 is configured to be able to rotate around the Z axis (axis of rotational symmetry when the wafer 2 is viewed as a substantially circular shape).

  The illumination optical system 10 includes a light source 11 (for example, a white LED or a halogen lamp), a condenser lens 12, an illuminance uniformizing unit 13, an aperture stop 14 in order of arrangement from the left side to the right side in FIG. A field stop 15, a collimator lens 16, and a detachable polarizer 17 are included.

  Here, the light emitted from the light source 11 of the illumination optical system 10 is guided to the aperture stop 14 and the field stop 15 via the condenser lens 12 and the illuminance equalizing unit 13. The illuminance uniformizing unit 13 scatters illumination light and uniformizes the light quantity distribution. An interference filter can also be included. The aperture stop 14 and the field stop 15 are configured such that the size and position of the opening can be changed with respect to the optical axis of the illumination optical system 10. Therefore, in the illumination optical system 10, by operating the aperture stop 14 and the field stop 15, the size and position of the illumination area can be changed and the aperture angle of the illumination can be adjusted. The light that has passed through the aperture stop 14 and the field stop 15 is collimated by the collimator lens 16, passes through the polarizer 17, and enters the half mirror 7.

  The polarizer 17 is set so that its transmission axis is oriented in the Y-axis direction on the wafer 2, and makes light from the collimator lens 16 linearly polarized light. Thereby, the illumination light irradiated on the surface of the wafer 2 becomes linearly polarized light. At this time, the wafer stage 5 is rotated so that the repeating direction of the repeating pattern 3 on the wafer 2 is inclined at an angle of 45 degrees with respect to the X-axis direction. That is, the angle formed by the vibration direction of the linearly polarized light on the surface of the wafer 2 and the repeating direction of the repeating pattern 3 is set to 45 degrees (see FIG. 2). The angle is not limited to 45 degrees, and can be set in an arbitrary angle direction such as 22.5 degrees or 67.5 degrees.

  The half mirror 7 reflects light from the illumination optical system 10 downward and guides it to the objective lens 6. Thereby, the wafer 2 is incidentally illuminated by the light (linearly polarized light) from the illumination optical system 10 that has passed through the objective lens 6. On the other hand, the light incident on the wafer 2 is reflected by the wafer 2, returns to the objective lens 6 again, passes through the half mirror 7, and can enter the detection optical system 20.

  The detection optical system 20 includes a detachable analyzer 21, a lens 22, a half prism 23, a belt run lens 24, and a field stop 25 in the order of arrangement from the lower side to the upper side in FIG. 1. Is done. The analyzer 21 is configured to be able to rotate the azimuth (polarization direction) of the transmission axis around the optical axis of the detection optical system 20 using the rotation drive device 26. The azimuth of the transmission axis of the analyzer 21 is the above-mentioned. It is set so as to be inclined at an inclination angle of about 90 degrees with respect to the transmission axis of the polarizer 17. That is, the analyzer 21 is arranged so as to be in a crossed Nicols state (a state in which the polarization directions are orthogonal) with respect to the polarizer 17 of the illumination optical system 10, and the crossed Nicols state can be intentionally broken. ing.

  Then, when the specularly reflected light from the surface of the wafer 2 that has passed through the half mirror 7 passes through the analyzer 21, as a polarized light component whose vibration direction is substantially perpendicular to the vibration direction of linearly polarized light that is illumination light in the specularly reflected light. The second linearly polarized light is guided to the imaging surfaces of the first and second imaging elements 31 and 32 by the half prism 23. When the polarizer 17 of the illumination optical system 10 and the analyzer 21 of the detection optical system 20 satisfy the crossed Nicols condition, the light is received by the detection optical system 20 unless the polarization main axis rotates in the repeated pattern 3 of the wafer 2. The amount of light that comes close to zero.

  The half prism 23 branches the incident light beam in two directions. One light beam passing through the half prism 23 forms an image of the surface of the wafer 2 on the field stop 25 via the belt-run lens 24 and projects an image of the pupil plane of the objective lens 6 onto the first image sensor 31. Therefore, the luminance distribution on the pupil plane of the objective lens 6 is reproduced on the imaging surface of the first image sensor 31, and an image (Fourier image) of the wafer 2 that is Fourier transformed by the first image sensor 31 can be captured. It is. The Bertrand lens is generally a converging lens that connects the image of the rear focal plane of the objective lens to the focal plane of the eyepiece, but an optical system such as a microscope is generally telecentric on the image side. Since the rear focal plane of the objective lens is the pupil plane, in this embodiment, the lens 24 that forms an image of the pupil plane of the objective lens 6 on the imaging plane of the first imaging element 31 is referred to as a belt run lens 24. .

  The field stop 25 can change the aperture shape in a plane perpendicular to the optical axis of the detection optical system 20. Therefore, the first image sensor 31 can detect information in an arbitrary region of the wafer 2 by operating the field stop 25. The other light beam passing through the half prism 23 is guided to a second image sensor 32 for capturing an image of a normal wafer 2 that has not undergone Fourier transform.

  Here, the relationship between the incident angle of the illumination light on the wafer 2 and the imaging position in the pupil plane will be described with reference to FIG. As shown by the broken line in FIG. 3, when the incident angle of the illumination light to the wafer 2 is 0 °, the image formation position on the pupil is the pupil center. On the other hand, as shown by the solid line in FIG. 3, when the incident angle is 64 ° (corresponding to NA = 0.9), the imaging position on the pupil is the outer edge of the pupil. That is, the incident angle of the illumination light on the wafer 2 corresponds to the radial position in the pupil on the pupil. Further, the light that forms an image at a position within the same radius from the optical axis in the pupil is light that is incident on the wafer 2 at the same angle.

  The first image sensor 31 is a two-dimensional image sensor such as a CCD or a CMOS, images (detects) the Fourier image described above, and outputs a detection signal to the arithmetic processing unit 40. If a CMOS image sensor is used as the first image sensor 31, the readout area can be freely set in units of pixels, so that only necessary pixel data (optical information) can be read out at high speed. In that case, a circuit that enables such partial reading is provided on the first imaging element 31 (on-chip).

  The arithmetic processing unit 40 evaluates the state of the repeated pattern 3 based on the detection signal of the Fourier image input from the first image sensor 31. Then, the evaluation result of the repeated pattern 3 by the arithmetic processing unit 40 and the Fourier image at that time are output and displayed on the monitor 45.

  A method for evaluating the repeated pattern 3 using the evaluation apparatus 1 of the present embodiment will be described with reference to the flowchart shown in FIG. The inventor of the present application uses two Fourier images obtained by rotating the analyzer 21 so that the orientation of the transmission axis of the analyzer 21 is 90 ° ± 3 ° with respect to the transmission axis of the polarizer 17. As a result of comparing the non-defective pattern with the pattern to be evaluated, the difference in signal intensity is found to correlate with the change in the width of the line portion (hereinafter referred to as line width change) caused by the change in dose. It was. Further, signals for each pixel in two Fourier images picked up by rotating the analyzer 21 so that the orientation of the transmission axis of the analyzer 21 is 90 ° ± 3 ° with respect to the transmission axis of the polarizer 17. As a result of comparing the non-defective pattern with the pattern to be evaluated with respect to the average intensity, it was found that there was a correlation with a change in LER (Line Edge Roughness) caused by a change in focus. Note that LER is a value representing the size of the irregularities formed on the wall surface of the pattern.

  Therefore, first, the wafer 2 to be evaluated is transferred to the wafer stage 5, and the pattern to be evaluated (a part of one shot) on the wafer 2 is moved below the objective lens 6 by the wafer stage 5. (Step S101). After the wafer 2 is transferred, alignment is performed so that the repeating direction of the repeating pattern 3 is inclined by 45 degrees with respect to the illumination direction (the traveling direction of linearly polarized light on the surface of the wafer 2). The alignment angle is not limited to 45 degrees, and may be 67.5 degrees or 22.5 degrees.

  As described above, the analyzer 21 is configured to be able to rotate the azimuth (polarization direction) of the transmission axis by using the rotation drive device 26, and after the wafer 2 is transported and aligned, the analyzer 21 transmits the light. The analyzer 21 is rotated so that the axis orientation is at an inclination angle of 90 degrees + 3 degrees (93 degrees) with respect to the transmission axis of the polarizer 17 (step S102). At this time, the vibration direction in the plane perpendicular to the traveling direction of the linearly polarized light that is the illumination light, and the vibration direction in the plane perpendicular to the traveling direction of the second linearly polarized light (regular reflection light) extracted by the analyzer 21. Is set to 90 degrees + 3 degrees (93 degrees).

  Next, the surface of the wafer 2 is irradiated with linearly polarized light, and specularly reflected light (elliptical polarized light) reflected by the surface of the wafer 2 is detected and imaged by the first image sensor 31 via the analyzer 21 (step S103). At this time, the illumination light emitted from the light source 11 passes through the aperture stop 14 and the field stop 15 via the condenser lens 12 and the illuminance equalizing unit 13, and is converted into parallel light by the collimator lens 16 and then the polarizer. After passing through 17 and reflected by the half mirror 7, the wafer 2 is irradiated through the objective lens 6. The specularly reflected light from the wafer 2 passes through the objective lens 6 and the half mirror 7 and enters the detection optical system 20, and the light incident on the detection optical system 20 includes the analyzer 21, the lens 22, and the half prism 23. The Fourier image passes through the belt run lens 24 and the field stop 25 and is projected onto the imaging surface of the first imaging element 31. The first image sensor 31 photoelectrically converts the Fourier image of the second linearly polarized light formed on the imaging surface to generate a detection signal, and outputs the detection signal to the arithmetic processing unit 40.

  When the detection signal of the Fourier image by the second linearly polarized light is input to the arithmetic processing unit 40, it is stored in an internal memory (not shown) of the arithmetic processing unit 40 (step S104). Here, an example of a Fourier image is shown in FIG. FIG. 6 shows the amount of light when the reflected light from the repetitive pattern 3 reaches the inside of the pupil through the analyzer 21 when the wavelength of the illumination light is 546 nm and the incident angle is 60 ° (that is, It is the figure which calculated | required by calculation the light quantity in a Fourier image.

  Next, the analyzer 21 is rotated so that the orientation of the transmission axis of the analyzer 21 is 90 ° ± 3 ° with respect to the transmission axis of the polarizer 17, and a Fourier image is captured under each condition. It is determined whether or not (step S105). When determination is No, it progresses to step S106 and the analyzer 21 is set so that the azimuth | direction of the transmission axis of the analyzer 21 may become an inclination angle of 90 degrees-3 degrees (87 degrees) with respect to the transmission axis of the polarizer 17. After the rotation, the imaging in step S103 and the image storage in step S104 are repeated, and the process returns to step S105. At this time, the angle formed by the vibration direction in the plane perpendicular to the traveling direction of the linearly polarized light that is the illumination light and the vibration direction in the plane perpendicular to the traveling direction of the second linearly polarized light extracted by the analyzer 21 is , 90 degrees to 3 degrees (87 degrees).

  On the other hand, when the determination in step S105 is Yes, the process proceeds to step S107, and the wafer 2 is recovered. As a result, two images with different orientations of the transmission axes of the analyzer 21 are stored. Note that the rotation angle range of the analyzer 21 is preferably in the range of ± 3 degrees to ± 5 degrees because the larger the amount of luminance change in a defective shot, the larger the noise component (other than the amount of polarization change). .

  When the wafer 12 is collected, the image processing unit 50 reads out the two images captured and acquired in the previous step from the internal memory (step S108), and calculates the difference and the average of the signal intensity in the two read images by image processing. Obtained (step S109). In order to obtain the difference in signal strength, for example, the difference in signal strength between portions suitable for evaluation (for example, the portion R in FIG. 6) in two Fourier images is obtained in pixel units, and the difference obtained in pixel units is calculated. The average value is calculated as a difference value of signal strength. In order to obtain the average signal intensity, for example, the average of the signal intensity of the part suitable for evaluation (for example, the R part in FIG. 6) in two Fourier images is obtained in pixel units, and the average obtained in pixel units is calculated. The average value is calculated as the average value of signal intensity. It should be noted that the region for obtaining the difference and the average of the signal intensity is not limited to the portion R in FIG. 6 according to the portion suitable for the evaluation in the two Fourier images, but U, D, L, and other portions are selected. You can do it. If a CMOS image sensor is used as the first image sensor 31, the readout area can be freely set in units of pixels, so that only pixel data in a portion suitable for pattern evaluation can be read out at high speed.

  When the difference value and the average value of the signal intensity are obtained, the line width change (that is, the state change of the repetitive pattern 3) caused by the change of the dose amount (exposure amount) (from the appropriate value) is obtained from the obtained difference value. (Step S110). At this time, the arithmetic processing unit 40 obtains the line width change by, for example, comparing the obtained difference value with a data table in which the correlation between the signal intensity difference and the line width change is obtained in advance.

  Next, the LER (that is, the state change of the repetitive pattern 3) resulting from the change in focus (from the appropriate value) is obtained from the obtained average value, and the evaluation of the repetitive pattern 3 is finished (step S111). At this time, the arithmetic processing unit 40 obtains the LER, for example, by comparing the obtained average value with a data table in which the correlation between the average signal intensity and the LER is obtained in advance. The line width change and LER obtained in this way are displayed on the monitor 55 together with the two Fourier images, and when the line width change or LER exceeds a predetermined threshold value, this is indicated as a dose failure or a focus failure. Informed.

  As described above, according to the evaluation apparatus 1 and method of the present embodiment, the angle condition between the vibration direction of the linearly polarized light that is the illumination light and the vibration direction of the second linearly polarized light extracted by the analyzer 21 is changed. By evaluating the state of the repetitive pattern 3 based on the two Fourier images picked up in this way, it is possible to discriminate and detect a dose defect and a focus defect, and to identify the cause of the abnormality of the repetitive pattern 3 Is possible.

  At this time, an angle formed by the vibration direction in the plane perpendicular to the traveling direction of the linearly polarized light that is the illumination light and the vibration direction in the plane perpendicular to the traveling direction of the second linearly polarized light extracted by the analyzer 21 is defined. , 90 ° ± 3 ° can be set, and the state of the repeated pattern 3 can be evaluated with high sensitivity.

  At this time, based on the difference in signal intensity (luminance) between the two Fourier images, the state change (line width change) of the repetitive pattern 3 due to the change in the dose amount (exposure amount) in the exposure apparatus is detected, By detecting the state change (LER) of the repetitive pattern 3 caused by the focus change in the exposure apparatus based on the average of the signal intensity (luminance) in the two Fourier images, the dose failure and the focus failure can be reliably detected. It can be determined and detected.

  At this time, the size of the apparatus can be reduced by illuminating the surface of the wafer 2 with epi-illumination.

  In the above-described embodiment, the repeated pattern 3 formed on the surface of the wafer 2 is evaluated. However, the present invention is not limited to this. For example, a pattern formed on a glass substrate can be evaluated. It is.

It is a schematic diagram of an evaluation apparatus. It is a figure explaining the inclination state of the vibration direction of linearly polarized light, and the repeating direction of a repeating pattern. It is explanatory drawing which shows the relationship between the incident angle of the illumination light to a wafer, and the imaging position in a pupil. It is a flowchart which shows the evaluation method of a pattern. It is a figure which shows an example of a Fourier image. It is the figure which calculated | required the light quantity when the regular reflection light from a repetitive pattern permeate | transmits an analyzer and arrived in a pupil when the wavelength of illumination light is 546 nm and an incident angle is 60 degrees.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Evaluation apparatus 2 Wafer (substrate) 3 Repeat pattern 10 Illumination optical system (illumination part) 17 Polarizer 20 Detection optical system (optical system) 21 Analyzer 26 Rotation drive apparatus (setting part)
31 1st image sensor (detection part)
40 arithmetic processing unit (evaluation unit)

Claims (8)

An illumination unit that irradiates the surface of the substrate having a predetermined repeating pattern with linearly polarized light;
An optical system for receiving a polarized light component having a vibration direction different from that of the linearly polarized light among the regularly reflected light from the repeated pattern irradiated with the linearly polarized light;
A detection unit for detecting the polarization component in a pupil plane of the optical system or a plane conjugate with the pupil plane;
A setting unit for setting an angle condition between the vibration direction of the linearly polarized light and the vibration direction of the polarization component;
An evaluation unit that evaluates the state of the repetitive pattern based on the polarization component detected by the detection unit;
The detection unit detects the polarization components obtained by setting the relationship between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set by the setting unit to a plurality of angle conditions,
The evaluation unit evaluates the state of the repetitive pattern based on information on the plurality of polarization components detected by the detection unit.   The setting unit is configured to determine an angle formed by a vibration direction in a plane perpendicular to the traveling direction of the linearly polarized light and a vibration direction of the polarization component in a plane perpendicular to the traveling direction of the regular reflected light by 90 degrees ± predetermined. The evaluation apparatus according to claim 1, wherein the evaluation apparatus is set to satisfy two angle conditions that are angles. The repeating pattern is formed using an exposure apparatus,
The detection unit detects the polarization component obtained in two angular conditions between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set by the setting unit;
The evaluation unit detects a change in state of the repetitive pattern due to a change in exposure amount in the exposure apparatus based on a difference in signal intensity corresponding to the two polarization components detected by the detection unit, 3. The evaluation apparatus according to claim 1, wherein a state change of the repetitive pattern caused by a focus change in the exposure apparatus is detected based on an average of signal intensities corresponding to the two polarization components. .   The evaluation apparatus according to claim 1, wherein the illumination unit irradiates the surface of the substrate with the linearly polarized light by epi-illumination. The surface of the substrate having a predetermined repetitive pattern is irradiated with linearly polarized light, and a polarized light component having a vibration direction different from that of the linearly polarized light from the repetitive pattern irradiated with the linearly polarized light is received. An evaluation method for evaluating the state of the repetitive pattern by detecting the polarization component in the pupil plane of the optical system or a plane conjugate with the pupil plane,
A first step of setting an angular condition between the vibration direction of the linearly polarized light and the vibration direction of the polarization component;
A second step of setting the relationship between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set in the first step to a plurality of angular conditions, and irradiating the surface of the substrate with the linearly polarized light;
A third step of receiving a polarized light component having a vibration direction different from that of the linearly polarized light among the regularly reflected light from the repetitive pattern irradiated with the linearly polarized light under the plurality of angle conditions;
A fourth step of detecting the polarization component in the pupil plane of the optical system received in the third step or a plane conjugate with the pupil plane in the plurality of angle conditions;
And a fifth step of evaluating the state of the repetitive pattern based on information of the plurality of polarization components respectively detected in the fourth step under the plurality of angle conditions.   In the first step, an angle formed by a vibration direction in a plane perpendicular to the traveling direction of the linearly polarized light and a vibration direction of the polarization component in a plane perpendicular to the traveling direction of the regular reflection light is 90 degrees. 6. The evaluation method according to claim 5, wherein two angle conditions that are ± predetermined angles are set. The repeating pattern is formed using an exposure apparatus,
In the second step, the surface of the substrate is irradiated with the linearly polarized light under two angular conditions between the vibration direction of the linearly polarized light and the vibration direction of the polarization component set in the first step,
In the third step, in the two angular conditions, a polarized light component having a vibration direction different from the linearly polarized light among the regular reflected light from the repetitive pattern irradiated with the linearly polarized light is received,
In the fourth step, the polarization component on the pupil plane of the optical system received in the third step or a plane conjugate with the pupil plane is detected under the two angle conditions,
In the fifth step, based on the difference in signal intensity corresponding to the two polarization components detected in the fourth step, the state change of the repetitive pattern caused by the change in the exposure amount in the exposure apparatus is performed. 7. The state change of the repetitive pattern caused by a change in focus in the exposure apparatus is detected based on an average of signal intensities corresponding to the two polarization components. The evaluation method described.   In the said 2nd step, the said linearly polarized light is irradiated to the surface of the said board | substrate by epi-illumination, The evaluation method as described in any one of Claim 5 to 7 characterized by the above-mentioned.