JP2007011169A - Method for inspecting phase shift mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for inspecting a phase shift mask by which drawing pattern data are accurately corrected to obtain pattern inspection data, no discrepancy is generated in the pattern inspection data with respect to image data obtained in a pattern defect inspection device, and a defect can be detected with high accuracy by comparing the pattern inspection data and the image data, in the inspection of a pattern defect in an auxiliary pattern type phase shift mask having a light shielding pattern where phase shift portions are adjoining through a light shielding portion. <P>SOLUTION: The method includes the steps of: obtaining image data of a light shielding pattern by inspection light using a pattern defect inspection device; converting the pattern data for drawing a light shielding pattern into pattern inspection data with correction based on dimensional changes in the light shielding pattern image due to a difference in the inspection light intensity passing the phase shift portion and a non-phase shift part, according to the distance between the phase shift portions adjoining through at least a light shielding portion; and comparing the image data with the pattern inspection data to detect a pattern defect in the phase shift mask. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for inspecting a phase shift mask, and more particularly, to a method for inspecting a pattern defect in a phase shift mask including a pattern arrangement in which a phase shift portion is adjacent via a light shielding portion.

  2. Description of the Related Art Conventionally, a phase shift mask having a high resolution limit has been proposed and put into practical use in a photolithography process with high integration and circuit pattern miniaturization in a large scale integrated circuit (LSI). There are various types of phase shift masks such as Levenson type, edge cooperative type, auxiliary pattern type, chromeless type, and halftone type. For example, Levenson type phase shift masks are formed on a transparent substrate with a metal film such as chrome. When the light-shielding part and the light-transmitting part exist repeatedly as in the line and space pattern, the transmitted light transmitted through the adjacent light-transmitting part via the light-shielding part is configured. The phase is configured to be shifted by 180 °. Since the phase of the transmitted light transmitted through these light transmitting portions is shifted, the resolution is prevented from being lowered due to interference of diffracted light, and the resolution of the line and space pattern can be improved.

  In such a phase shift mask, the optical path of [λ (2m−1) / 2] (∵m is a natural number) with respect to the transmitted light having the wavelength λ between the light transmitting parts adjacent via the light shielding part. By producing a length difference, a phase difference of 180 ° is produced between these transmitted lights. In order to generate such an optical path length difference, when the transparent substrate thickness difference d between the light transmitting portions adjacent to each other through the light shielding portion is n, the refractive index of the transparent substrate is expressed as [d = λ (2m-1) / 2n] may be satisfied.

  In the phase shift mask, in order to cause a difference in the thickness of the transparent substrate between the light transmitting portions, the transparent thin film is deposited on the transparent substrate in one light transmitting portion, or the thickness is increased. The thickness is reduced by engraving the transparent substrate in the light transmitting part. That is, the phase shift portion of the shifter-attached type (convex type) phase shift mask in which a transparent thin film is deposited on a transparent substrate is a transparent thin film (shifter) having a thickness d (= λ (2m−1) / 2n). ). Further, in the phase shift portion of the engraved phase shift mask in which the transparent substrate is engraved, the transparent substrate is etched by a depth d (= λ (2m−1) / 2n). When the transparent thin film is not deposited or engraved, or when the translucent part has a shallow engraving portion and a deep engraving portion, the shallow engraving portion becomes a non-phase shift portion.

  By the way, one of the major causes of a decrease in the product yield of LSI is a pattern defect of the phase shift mask. That is, pattern defects generated in the phase shift mask are transferred onto the wafer during pattern transfer, and defects are generated in the transferred pattern, resulting in a decrease in product yield.

  Pattern defects include defects in the light-shielding portion of the light-shielding pattern, such as chipping, edge defects, pinholes, and protrusions, pattern missing, and particle adhesion. Therefore, researches on pattern defect inspection methods for detecting pattern defects on phase shift masks have been actively conducted and put into practical use.

  Pattern defect inspection methods can be roughly divided into two types. A first type of pattern defect inspection method is a method of detecting pattern defects by observing two chips to which the same pattern has been transferred using a pattern defect inspection apparatus and comparing them. (Die to die inspection method). A second type of pattern defect inspection method has a predetermined relationship between measurement pattern data obtained by observing a chip to which a pattern is transferred using a pattern defect inspection apparatus, and drawing pattern data stored in a database. This is a method (die to database inspection method) in which a difference portion is detected by comparing with pattern inspection data created by conversion according to the above. Among these pattern defect inspection methods, when the photomask has a plurality of chips to which the same pattern is transferred, die-to-die inspection is possible, but the photomask has a plurality of chips to which the same pattern is transferred. If not, die-to-database inspection is required, and in recent years, there has been a tendency to adopt a die-to-database inspection method.

  As shown in FIG. 8, the pattern defect inspection apparatus includes an illumination optical system 201 that irradiates a phase shift mask with inspection light, and data collection means 202 that collects image data of the phase shift mask. . The data collection unit 202 includes an objective lens 203, a positioning mechanism 204, and a detector 205 that obtains image data. Further, in order to execute the die-to-database inspection method using this pattern defect inspection apparatus, the drawing pattern data is read from the database 207 by the data generation means 206 as described in Patent Document 1. Correction is performed to obtain pattern inspection data, and the comparison unit 208 compares the image data obtained by the detector 205 with the pattern inspection data.

  And in this patent document 1, the data which corrected the dimensional change of the light-shielding pattern resulting from the difference in the light intensity between the phase shift part of a Levenson type | mold phase shift mask and a non-phase shift part as pattern inspection data are used. The use is described. Specifically, for the line and space pattern in which the phase shift unit and the non-phase shift unit are alternately arranged via the light shielding unit, the phase shift unit and the non-phase shift unit are changed according to the pattern size. It is described that a bias amount for correcting a difference in light intensity of inspection light passing therethrough is calculated, and pattern data for drawing is corrected to be pattern inspection data.

  It is known that the inspection light passing through the phase shift part has lower light intensity than the inspection light passing through the non-phase shift part due to the influence of the dark part caused by the scattered light from the side wall edge of the engraved part. ing.

  In this way, by using pattern inspection data that is corrected by applying a bias (minus sizing) in advance to the portion corresponding to the phase shift portion in the drawing pattern data, the pattern inspection data is made closer to the image data, and pattern inspection is performed. It becomes possible to reduce the noise component in.

  On the other hand, Patent Document 2 describes an auxiliary pattern type phase shift mask. As shown in FIG. 9, the auxiliary pattern type phase shift mask is formed so as to surround the non-phase shift portion 301 along each side of the non-phase shift portion 301 having a rectangular shape and the non-phase shift portion 301. A phase shift unit 302 is included, and a region other than the non-phase shift unit 301 and the phase shift unit 302 has a light shielding pattern in which the light shielding unit 303 is formed. The light shielding pattern that forms the phase shift portion 302 is a pattern that is below the resolution limit of exposure light, and improves the resolution of the transfer pattern of the rectangular light shielding pattern that forms the non-phase shift portion 301.

  In such a light shielding pattern of the auxiliary pattern type phase shift mask, the phase shift portions 302 are adjacent to each other via the light shielding portion 303, and the line pattern is the same as the Levenson type phase shift mask described above. -There is a feature different from the pattern arrangement in which the phase shift portions are alternately arranged in the light transmitting portions in the AND space pattern.

JP 2003-162043 A Japanese Patent No. 2710967

  By the way, it described in patent document 1 with respect to the phase shift mask which has the light shielding pattern containing the phase shift part adjacent via a light shielding part like the auxiliary | assistant pattern type phase shift mask described in patent document 2 When the phase shift mask inspection method is applied, the bias amount is determined in consideration of only the pattern dimensions, and the pattern data for drawing is corrected to obtain pattern inspection data. The data differs from the image data obtained by the pattern defect inspection apparatus, and it is difficult to detect defects by comparing the pattern inspection data and the image data.

  That is, as shown in FIG. 10A, the bias amount is set with respect to the phase shift mask having the light shielding pattern including the phase shift portion 302 adjacent through the light shielding portion 303 in consideration of only the dimension of the pattern. When the drawing pattern data is determined and corrected, as shown in FIG. 10B, correction is performed to uniformly reduce the dimensions of the phase shift unit 302, and the optical system of the pattern defect inspection apparatus is further corrected. As shown in (c) of FIG. 10, pattern inspection data is obtained. This pattern inspection data does not coincide with the image data shown in (d) of FIG. 10, particularly when the distance D between the phase shift units 302 and 302 is short. Therefore, pattern defects in the phase shift mask cannot be accurately detected based on the pattern inspection data.

  Accordingly, an object of the present invention is to improve the inspection accuracy of the die-to-database inspection method, which has hitherto been insufficient in inspection accuracy with respect to the phase shift mask. In particular, the phase shift portions are adjacent to each other via the light shielding portion. In pattern defect inspection of a phase shift mask having a predetermined pattern arrangement, pattern inspection data is obtained by accurately correcting drawing pattern data to obtain pattern inspection data. It is an object of the present invention to provide a phase shift mask inspection method capable of accurately detecting defects by comparing these pattern inspection data and image data.

  As described above, in the conventional phase shift mask inspection method, a bias (minus sizing) is applied to the phase shift portion in the pattern inspection data in order to reflect the optical characteristics of the phase shift portion in the pattern inspection data. Although it corresponds, in the auxiliary pattern type phase shift mask, there is a pattern that cannot be handled by a uniform bias (sizing in the minus direction).

  Accordingly, the phase shift mask inspection method according to the present invention has any one of the following configurations.

[Configuration 1]
A phase shift mask having a light shielding pattern comprising a light shielding part and a light transmitting part on a transparent substrate, the light transmitting part comprising a phase shift part and a non-phase shift part, and a phase shift part including a pattern arrangement adjacent to each other via the light shielding part In the inspection method, a step of obtaining image data of a light shielding pattern by inspection light using a pattern defect inspection apparatus, and a pattern pattern data for drawing a light shielding pattern of a phase shift mask between at least adjacent phase shift portions via a light shielding portion A step of converting to pattern inspection data to which correction based on a change in dimension of a light-shielding pattern image caused by a difference in light intensity of inspection light passing through a phase shift unit and a non-phase shift unit according to a distance, image data, And a step of detecting pattern defects of the phase shift mask by comparing with pattern inspection data.

[Configuration 2]
In the inspection method for the phase shift mask having the configuration 1, the correction is performed by reducing the drawing pattern data for a portion where the distance between the phase shift portions adjacent to each other through the light shielding portion is larger than a predetermined value. The correction is performed to enlarge the drawing pattern data for a portion where the distance between the portions is smaller than a predetermined value.

[Configuration 3]
In the phase shift mask inspection method having the configuration 2, the correction is performed by extracting a part where the distance between adjacent phase shift parts is smaller than a predetermined value from the drawing pattern data via the light shielding part. Further, correction for enlarging the drawing pattern data is performed, and correction for reducing the drawing pattern data is performed on the phase shift unit other than the extracted portion.

[Configuration 4]
In the phase shift mask inspection method having any one of Configurations 1 to 3, the phase shift portion is formed by carving a transparent substrate to a predetermined depth. .

  In the phase shift mask inspection method according to the present invention having such a configuration, the drawing pattern data is corrected according to the distance between the adjacent phase shift portions via at least the light shielding portion to obtain pattern inspection data. Therefore, high-precision inspection is possible even in the pattern inspection of the auxiliary pattern type phase shift mask having a specific pattern that cannot be dealt with by a uniform bias.

  In the phase shift mask inspection method according to the present invention, the pattern data for drawing is corrected according to the distance between adjacent phase shift portions via at least a light shielding portion to obtain pattern inspection data. In the pattern inspection of the auxiliary pattern type phase shift mask having a specific pattern that cannot be dealt with, highly accurate inspection is possible.

  That is, the present invention improves the inspection accuracy of the die-to-database inspection method in which the inspection accuracy for the phase shift mask was insufficient, and in particular, the pattern arrangement in which the phase shift portions are adjacent to each other via the light shielding portion In the pattern defect inspection of the auxiliary pattern type phase shift mask having the above, by properly correcting the pattern data for drawing and obtaining the data for pattern inspection, the difference in the pattern inspection data with respect to the image data obtained by the pattern defect inspection apparatus It is possible to provide a phase shift mask inspection method capable of accurately detecting defects by comparing the pattern inspection data and the image data without generating a noise component.

  Hereinafter, embodiments of a phase shift mask inspection method according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below.

  First, a method for manufacturing an auxiliary pattern type phase shift mask will be described. First, as shown in FIG. 1A, a chromium film 102 is deposited as a light shielding body on a transparent substrate 101 made of quartz or the like, and a first resist film 103 is applied on the chromium film 102. . Next, the resist film 103 is subjected to electron beam drawing and developed to form a resist pattern as shown in FIG. The chromium film 102 is patterned (dry etching) in accordance with the resist pattern to form a light shielding portion of the light shielding pattern. Then, as shown in FIG. 1C, when the resist film 103 is peeled off and washed, only the patterned chromium film 102 remains on the transparent substrate 101.

  Next, as shown in FIG. 1D, a second resist film 104 is applied on the chromium film 102 patterned as a light shielding pattern, and a shifter pattern is formed by electron beam drawing. Then, the resist film 104 is developed to form an etching mask that exposes a predetermined portion between the light shielding portion and the light shielding portion (translucent portion) as shown in FIG. Next, when the transparent substrate 101 is dry-etched using an etching mask to form an engraving, an engraved portion 105 is formed.

  Then, as shown in FIG. 1 (f), when the resist film 104 is peeled off and washed, a single-engraved engraved phase shift mask is produced. In such a single-engraved engraving type phase shift mask, the pattern of the engraved portion 105 is a phase shift portion, and the light transmitting portion pattern on the same substrate surface as the transparent substrate 101 is a non-phase shift portion.

  This phase shift mask inspection method is a phase shift mask inspection method having a light shielding pattern composed of a light shielding portion and a light transmitting portion on a transparent substrate 101 as shown in FIG. 1, and detects a pattern defect. Is for. The translucent part is composed of a phase shift part and a non-phase shift part. The light shielding pattern of the phase shift mask includes a pattern arrangement in which the phase shift unit 302 is adjacent to the light through the light shielding unit 303 as shown in FIG. The light shielding part 303 of the light shielding pattern includes a semi-transparent part.

  The pattern defects include a light shielding pattern defect (a white defect occurring in the light shielding pattern or a black defect occurring in the light transmitting part) and a phase defect in the phase shift part (a defect having a phase difference different from other phase shift parts). )including. As for the phase defect, a phase difference from other phase shift portions occurs in the image by the inspection light.

  The phase shift unit 302 is either a carved mold (recessed mold) formed by carving a transparent substrate to a predetermined depth, or a shifter-coated mold (convex molded mold) in which a transparent thin film is deposited on the transparent substrate. It may be.

  Further, the phase shift mask inspection method according to the present invention can be executed using a pattern defect inspection apparatus as described above with reference to FIG. That is, the pattern defect inspection apparatus includes an illumination optical system 201 that irradiates inspection light onto the phase shift mask, and data collection means 202 that collects image data of the phase shift mask. The data collection means 202 includes an objective lens 203 to which transmitted light from the phase shift mask is incident, a positioning mechanism 204 for positioning the phase shift mask, and a detector 205 that receives the light beam that has passed through the objective lens 203 and obtains image data. It is configured. In order to execute the phase shift mask inspection method according to the present invention using this pattern defect inspection apparatus, the data generation means 206 reads and corrects the drawing pattern data from the database 207, and the pattern inspection data. The comparison unit 208 compares the image data obtained by the detector 205 with the pattern inspection data.

  FIG. 2 is a flowchart showing the procedure of the phase shift mask inspection method according to the present invention.

  In this phase shift mask inspection method, as shown in FIG. 2, first, in step st1, a pattern defect inspection apparatus is used to obtain image data of a light shielding pattern (light shielding pattern image) using inspection light.

  On the other hand, in step st2, the drawing pattern data (design data) for the light shielding pattern is corrected to be converted into pattern inspection data. In this correction, the dimensional change of the light-shielding pattern image due to the difference in the light intensity of the inspection light passing through the phase shift part and the non-phase shift part according to at least the distance between adjacent phase shift parts via the light shield part Correction based on the above shall be added. This correction value is a light-shielding pattern image caused by the difference in light intensity between the phase shift portion transmitted light and the non-phase shift portion transmitted light due to the waveguide effect based on the difference between the actual exposure wavelength and the inspection light wavelength. , Which can be obtained by experiments or the like.

  It is desirable to make the obtained correction value a rule base. That is, the correlation between the correction value (bias amount) and parameters such as the distance between adjacent phase shift portions through at least a light shielding portion, the pattern dimensions of other phase shift portions, and the pattern length of adjacent portions. It is desirable to define a table. By making the rule base in this way, the correction value is read from the rule base on the basis of the distance between the phase shift units adjacent via the light shielding unit and other parameters, and the pattern inspection data is quickly generated. be able to. Further, this correction includes correction corresponding to a change in the image in the optical system of the pattern defect inspection apparatus.

  Next, in step st3, the comparison unit compares the image data obtained by the pattern defect inspection apparatus with the pattern inspection data, and detects the pattern defect of the phase shift mask.

  FIG. 3 is a graph showing the relationship (intensity profile) between pattern inspection data and image data that have been subjected only to correction corresponding to image changes in the optical system.

  By the way, when comparing the pattern inspection data that has been corrected only in response to the image change in the optical system and the image data, the phase shift unit 302 (the engraving unit 105) is not close to each other as shown in FIG. At a location (A in FIG. 3), the light intensity in the image data is lower than the light intensity in the pattern inspection data. Therefore, at this location, it can be said that the pattern dimension in the pattern inspection data needs to be corrected (biased) in the direction of further reduction.

  However, at a location (B in FIG. 3) where adjacent phase shift portions 302 are close to each other via the light shielding portion, the light intensity in the image data is higher than the light intensity in the pattern inspection data. Therefore, at this location, it can be said that the pattern dimension in the pattern inspection data needs to be corrected (biased) in the direction of further expansion.

  Therefore, in the present invention, as shown in [Table 1] below, when the distance (D) between the phase shift units 302 adjacent to each other via the light shielding unit is smaller than a predetermined value (R), the phase is changed. The shift unit 302 performs correction for sizing only the sides facing each other through the light shielding unit in the enlargement direction, and the other part of the phase shift unit 302 is corrected for sizing in the reduction direction.

  FIG. 4 is a plan view showing correction performed on a phase shift unit adjacent to a part of the side via a light shielding unit.

  That is, as shown in FIG. 4, for the phase shift units 302 and 302 that are adjacent to each other only through a part of the side via the light shielding unit, the distance (D) between the phase shift units 302 and 302 is a predetermined value (R If smaller than (), correction for sizing in the enlargement direction is performed only for a part of the sides adjacent to each other.

  When the distance (D) between the phase shift portions is larger than a predetermined value (R), correction is performed so that the entire phase shift portion is uniformly sized in the reduction direction.

  FIG. 5 is a plan view showing the contents of drawing pattern data correction (when the interval D between phase shift portions is wide) for conversion to pattern inspection data.

  Specifically, in this phase shift mask inspection method, pattern inspection data is created as follows. First, as shown to (a) in FIG. 5, the drawing pattern data for forming the light-shielding part (chromium film pattern on a transparent substrate) in the light-shielding pattern is obtained. The drawing pattern data for forming the light-shielding portion is a resist pattern when the light-shielding body pattern 102 shown in FIG. 1B is formed in the engraving type phase shift mask creating method described above.

  Next, as shown in FIG. 5B, the drawing pattern data is corrected. At this time, in the above-described engraving type phase shift mask creation method, the phase shift portions adjacent to each other through the light shielding portion 303 based on the resist pattern when forming the engraved portion 105 shown in FIG. It is determined whether the distance (D) between 302 is smaller than a predetermined value (R).

  As a method for determining whether the distance (D) between the phase shift units 302 is smaller than a predetermined value (R), for example, by performing DRC processing (Design Ruie Check), the distance (D) between light shielding patterns is The method of extracting the location smaller than predetermined value (R) is mentioned. The DRC process is originally a process for checking whether there is a part that violates a design rule that is a basis of semiconductor device design in a design drawing. The software for performing the DRC processing usually has a function of extracting a light shielding pattern having a predetermined line width or a translucent portion and converting the extracted portion into data. Therefore, this function can be used to extract a portion to be sized in the enlargement direction.

  Then, correction is performed so that the portions that are not extracted as a result of the DRC processing are uniformly sized in the reduction direction. That is, when the distance (D) between the phase shift portions is larger than the predetermined value (R), correction is performed so that the entire phase shift portion is uniformly sized in the reduction direction in accordance with the correction values accumulated in the rule base. It will be.

  Further, as shown in FIG. 5C, correction corresponding to the change of the image in the optical system of the pattern defect inspection apparatus is performed to create pattern inspection data.

  The pattern defect inspection can be accurately performed by comparing and comparing the pattern inspection data and the image data of the phase shift mask obtained by the pattern defect inspection apparatus.

  FIG. 6 is a plan view showing the contents of drawing pattern data correction (when the interval D between phase shift portions is narrow) for conversion to pattern inspection data.

  Then, as shown in FIG. 6A, when it is determined that the distance (D) between the adjacent phase shift units 302 via the light shielding unit 303 is smaller than a predetermined value (R), the drawing is performed. In the correction of the pattern data for use, as shown in FIG. 6B, correction is performed so that only the side where the phase shift portion faces through the light shielding portion is sized in the enlargement direction, and the other parts of this phase shift portion Is corrected for sizing in the reduction direction. This correction is performed according to the correction value stored in the rule base.

  Further, as shown in FIG. 6C, correction corresponding to the change of the image in the optical system of the pattern defect inspection apparatus is performed to create pattern inspection data.

  The pattern defect inspection can be accurately performed by comparing and comparing the pattern inspection data and the image data of the phase shift mask obtained by the pattern defect inspection apparatus.

  Thus, in the phase shift mask inspection method according to the present invention, even when the distance between the adjacent phase shift portions is narrow via the light shielding portion, the dark portion generated by the scattered light from the side wall edge of the engraved portion. Mismatch between pattern inspection data and image data due to (waveguide effect) is corrected, and by comparing these, phase difference due to difference in wavelength between exposure wavelength and inspection light, waveguide effect, pattern defect Even if an image change such as a focus occurs in the optical system of the inspection apparatus, a pattern defect can be accurately detected.

  By the way, in this phase shift mask inspection method, the elements shown in the following [Table 2] can be considered as elements for determining the above-mentioned predetermined value (R), and these elements and the predetermined value (R) are considered. There is a relationship shown in [Table 2] below.

  That is, in the above-described correction of the drawing pattern data, the predetermined value (R) for the distance (D) between the phase shift portions adjacent to each other via the light shielding portion, that is, the side where the adjacent phase shift portions face each other. Should be changed based on the pattern dimensions of the adjacent phase shift portions and the lengths of the sides where these phase shift portions are opposed to each other.

  The correction value (correction amount) of the drawing pattern data should be determined in consideration of the pattern size of the phase shift portion as shown in [Table 3] below for the correction sizing in the reduction direction. is there.

  The correction value (correction amount) of the drawing pattern data is the distance (D between adjacent phase shift portions via the light-shielding portion, as shown in [Table 4] below, for the correction sizing in the enlargement direction. ), And should be determined in consideration of the pattern dimensions of the phase shift portions and the lengths of the sides where the phase shift portions face each other.

  FIG. 7 is a plan view showing phase shift units that are adjacent to each other via a light shielding unit and that are partially continuous (connected).

  As shown in FIG. 7, the phase shift unit 302 which is adjacent to and partially continuous (connected) through the light shielding unit 303 also relates to the correction of the drawing pattern data as described above. It can be corrected according to the rule base.

  That is, for correction sizing in the reduction direction, pay attention to the connected portion, and based on the pattern dimensions (line width and line length) of this portion (phase shift portion), as shown in [Table 3], the pattern dimensions When is large, the correction value (correction amount) is decreased.

  As for correction for sizing in the enlargement direction, pay attention to the unconnected portion, and as shown in [Table 4], these pattern dimensions (line width and line length) and the lengths of the opposing sides (inner sides) If the distance is large and the distance (D) between the phase shift portions is small, the correction value (correction amount) is increased.

It is sectional drawing which shows the process of producing a single-carving type engraving type | mold phase shift mask. It is a flowchart which shows the procedure of the inspection method of the phase shift mask which concerns on this invention. It is a graph which shows the relationship between the data for pattern inspection which performed only the correction | amendment corresponding to the change of the image in an optical system, and image data. In the inspection method of the phase shift mask, it is a plan view showing the correction to be performed on the phase shift portion adjacent to the part of the side through the light shielding portion. In the phase shift mask inspection method, it is a plan view showing the contents of correction of drawing pattern data for conversion to pattern inspection data (when the interval between phase shift portions is wide). In the phase shift mask inspection method, it is a plan view showing the details of correction of drawing pattern data for conversion to pattern inspection data (when the interval between phase shift portions is narrow). It is a top view which shows the phase shift part which adjoins via the light-shielding part, and one part is continued (connected). It is a block diagram which shows the structure of a pattern defect inspection apparatus. It is a top view which shows the structure of an auxiliary pattern type | mold phase shift mask. It is a top view which shows the correction content of the pattern data for drawing in the inspection method of the conventional phase shift mask.

Explanation of symbols

DESCRIPTION OF SYMBOLS 201 Illumination optical system 202 Data collection means 206 Data generation means 208 Comparison means 301 Non-phase shift part 302 Phase shift part 303 Light-shielding part

Claims (4)

A pattern arrangement having a light-shielding pattern composed of a light-shielding part and a light-transmitting part on a transparent substrate, the light-transmitting part comprising a phase shift part and a non-phase shift part, and the phase shift part being adjacent via the light-shielding part In a phase shift mask inspection method including:
A step of obtaining image data of the light shielding pattern by inspection light using a pattern defect inspection device;
The light intensity of the inspection light that passes through the phase shift part and the non-phase shift part according to the distance between the phase shift parts that are adjacent to each other through the light shielding part. A step of converting to pattern inspection data to which correction based on a dimensional change of the light shielding pattern image caused by the difference in
And a step of comparing the image data with the pattern inspection data to detect a pattern defect of the phase shift mask. The correction is correction for reducing the drawing pattern data for a portion where the distance between adjacent phase shift portions is larger than a predetermined value via the light shielding portion, and the distance between the phase shift portions is less than a predetermined value. The phase shift mask inspection method according to claim 1, wherein the correction is performed to enlarge the drawing pattern data for a small portion. In the correction, a portion where the distance between adjacent phase shift portions is smaller than a predetermined value via the light shielding portion is extracted from the drawing pattern data, and the drawing pattern data is enlarged for the extracted portion. The phase shift mask inspection method according to claim 2, wherein correction is performed and correction is performed to reduce the drawing pattern data for a phase shift unit other than the extracted portion. The phase shift mask inspection method according to any one of claims 1 to 3, wherein the phase shift portion is formed by carving the transparent substrate to a predetermined depth. .

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