JPS61251705A - Method and apparatus for inspecting pattern - Google Patents

Abstract

PURPOSE:To make inspection with high accuracy and high efficiency by picking up the images of a reference pattern for inspection and pattern to be inspected enlarging or reducing the image of either thereof, measuring the line width or the gap width between the lines concerning the part where the difference between said image and the other pattern is not zero and comparing the same with the reference for inspection. CONSTITUTION:The images of the standard pattern S switch is the reference for inspection and the pattern D to be inspected are picked up by image pickup devices 1a, 1b and are fed via an image distortion correcting circuit 3 and an image memory 11 to an enlarging and reducing circuit 12. The image of either of both patterns is enlarged or reduced to the size corresponding to the criterion in the circuit 12. The difference between the image of the one pattern which is enlarged or reduced and the image of the other pattern is determined in an arithmetic circuit 13 for the image and the line width or the gap width between the lines of the pattern is measured concerning the part where the difference is not zero in a width measuring circuit 15. The line width and gap width are further compared with the reference for inspection in an image processing controller 14, by which the defect of the pattern D to be inspected is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for detecting pattern defects, and more specifically, a method for inspecting patterns printed on IC wiring boards, etc., and a method used therefor. This paper proposes a device to do this.

[Prior art]

ICs (integrated circuits) are created by, for example, screen-printing a wiring pattern using conductive ink on a ceramic substrate and stacking multiple layers of these.
Inspection of pattern defects has become an important issue as the number of layers increases.

By the way, as a conventional method for inspecting wiring patterns, human visual inspection has generally been the method, but such methods have problems such as low product yield and low reliability due to oversight of pattern defects. In addition, efficiency and productivity are low, so for example, as in Japanese Patent Application No. 54-63940,
Using a defect-free pattern, i.e., an original pattern drawn as designed, as a reference, superimpose this on the pattern to be inspected to determine surplus and missing parts, or
- As in No. 93843, the pattern is automatically inspected using a method such as scanning the pattern to be inspected according to the designed pattern data, and if a scanning result different from the pattern data is detected, it is considered a defect. However, various devices for detecting such defects have been developed.

In particular, in the case of inspection equipment for IC masks, since the IC mask is created by etching, the boundaries of the pattern are relatively clear straight lines, and the data of the binary image of the pattern to be inspected is used as the inspection standard. It is sufficient to simply compare it with the standard pattern.

[Problem that the invention seeks to solve]

However, when wiring patterns are screen printed on ceramic substrates, it is inevitable that the boundaries of the pattern will have minute irregularities due to ink bleeding, screen mesh, etc. A simple comparison of the patterns determines that most of the irregularities at the pattern boundaries are defects. Therefore, inspection of patterns screen printed on ceramic substrates requires relatively more advanced technology than inspection of IC masks, etc. For example, digitized pattern data given as coordinate data is used as an inspection standard, and this and inspection A method of comparing a target pattern with a binarized image is known. However, with this method, it is necessary to convert the design data etc. into pixel format data as pattern data, but this requires a considerable amount of time, so it is not easy to handle when changing the pattern. Moreover, since the pattern to be inspected is scanned according to pattern data converted into pixel format, it is necessary to precisely match the reference positions, and a special distance meter or the like is required for this purpose. Furthermore, it has the disadvantage that it is difficult to apply to complex patterns.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and
Bleeding of ink in wiring patterns caused by screen printing, irregularities on pattern boundaries due to mesh, etc. are not judged as defects, there is no need to perform strict alignment, and high-speed processing is possible, making it easier to change patterns. Furthermore, the line width or gap width is measured at 45° intervals around the area where a defect is detected, and the minimum width is compared with the reference value. The present invention aims to provide a highly accurate and highly efficient pattern inspection method and apparatus by detecting defects in a target pattern.

The present invention images an inspection reference pattern and a pattern to be inspected, enlarges or reduces the image of either of the two patterns to a size corresponding to the judgment criterion, and Find the difference between the image and the image of the other pattern, measure the pattern line width or gap width between lines for areas where the difference is not 0, and compare the measured line width and gap width with inspection standards. The method is characterized in that defects in the pattern to be inspected are detected by.

[Principle of the invention]

The details of the present invention will be explained in the "Examples" section below, but the outline of the pattern inspection method according to the present invention will be explained below.

FIG. 1 is a schematic explanatory diagram of image processing performed by a pattern inspection apparatus according to the present invention.

In the figure, Db and sb are binarized images of a pattern D to be inspected and a standard pattern S, respectively, which will be described later. and,
For example, the binarized image sb of the standard pattern S is enlarged to create an enlarged image Sl, and the same is reduced to create a reduced image Ss. However, this enlargement or reduction is not enlargement or reduction in the usual sense, but image processing is performed by calculating the logical sum and logical product on a pixel basis, although the details will be described later. If the enlarged image St created in this way is subtracted from the image Db of the pattern to be inspected, the image W+(-
Db −S l ) is obtained, and if the image Db of the pattern to be inspected is subtracted from the small line image Ss, an image W2 (
−5S Db) is obtained. By adopting such a method, the standard pattern S and the enlarged image Sj!
The allowable range of the enlargement ratio between the standard pattern S and the reduced image Ss (both specifically expressed as the number of pixels) is set, and the edge of the pattern is fine. Even when inspecting a pattern that exhibits large irregularities, the irregularities on the edges will not be determined as defects.

Furthermore, based on the image Db of the pattern D to be inspected, a partial image T! of a predetermined square area centered on a position corresponding to the surplus portion extracted in the image W1 of the surplus portion is generated. Create. In this partial image Tl, as indicated by Φ to ■ in the figure, gaps (adjacent conductive parts in the wiring pattern The width of the gap (expressed in white in the figure) is measured, and if the minimum width linch is less than the minimum standard gap width of 20, it is determined that the product is defective. Similarly, based on the image Db of the pattern D to be inspected, a partial image T2 of a predetermined square area centered on the position corresponding to the missing part extracted in the image W2 showing the missing part is created. In this partial image T2, the width of the line (represented by hunting in the case of two conductive parts in the wiring pattern) is calculated in four directions at intervals of <45°, as indicated by ■ to ■ in the figure. If the minimum width 1whn is equal to or less than the minimum reference width 1to/of the line width, it is determined that the line is defective.

Therefore, in the present invention, as shown in FIG.
If the gap width of the surplus part is equal to or greater than the minimum standard width determined to avoid practical problems, and the line width of the missing part is also equal to or less than the minimum standard width, it is not determined to be a defect.This method is adopted. This makes it possible to eliminate the conventional process of visually inspecting defective areas again and determining whether the degree of missing or redundant patterns is beyond practical use, thereby increasing reliability. This makes it possible to improve performance and productivity.

(Examples) Hereinafter, the present invention will be described in detail based on drawings showing examples thereof.

FIG. 3 is a block diagram showing the overall configuration of a pattern inspection apparatus according to the present invention.

The inspection table 20 is placed horizontally on a base (not shown), and a standard pattern S serving as an inspection reference and a pattern D to be inspected can be placed on the top surface of the table 20 and moved in two orthogonal directions in the horizontal direction. It becomes. That is, the examination table 20
has a three-layer structure, and a pulse motor 31c fixed to the lowest layer support 21 fixed to the base moves the middle layer Y-direction moving table 23 in the depth direction (hereinafter referred to as Y-direction in FIG. 3).
Also, the pulse motor 31b fixed to the Y-direction moving table 23 moves the uppermost X-direction moving table 22 in the left-right direction in FIG. The X-direction movable table 22 on the top layer is configured to be moved in a direction perpendicular to the X-axis direction (hereinafter referred to as the X-axis direction).
It becomes possible to move in the X and Y rotation directions.

A fixed table 25 for fixedly placing a standard pattern S serving as an inspection reference is attached to a position near one end in the X-axis direction on the top surface of the inspection table 20, and a fixed table 25 is attached to a position near the other end in the X-axis direction. , a rotary table 24 on which the pattern D to be inspected is fixedly placed.
is provided.

The rotating table 24 is for correcting the angular deviation between the two patterns D and S, and is rotated with its rotating surface as a horizontal plane by a pulse motor 31a fixed to the top layer of the inspection table 20, that is, the X-direction moving table 22. The height position of the surface thereof is the same as the surface of the fixing base 250 for fixing the standard pattern S described above.

The production line for the pattern D to be inspected is in the Y-axis direction passing approximately near the center of the rotary table 24, as shown by the white arrow, and the pattern D to be inspected is transferred by a transfer machine (not shown).
is placed approximately at the center of the rotating table 24.

Two-dimensional imaging devices 1a and lb are placed above the examination table 20, with the optical axes of their lens systems directed vertically downward, and the distance and direction between the optical axes are the same as the distance between the centers of the fixed table 25 and the rotary table 24, and The re-imaging device 1a+
Ring strobes 2a and 2b are each fixed with the optical axis of the lb lens system as the center of their light emitting range.
The height positions of both ring strobes 2Ii and 2b are such that their light does not directly enter the lens systems of the re-imaging devices 1a and lb.

The image signals from the re-imaging devices 1a and 1b are provided to an image distortion correction circuit 3 to correct image distortion due to lens system aberrations, etc., and then provided to an image processing device 10.

The image processing device 10 includes an image memory 11, an enlargement/reduction circuit 12, an image calculation surface II! 13, Image processing controller 1
4, a width measuring circuit 15, and the like. This image processing device 10 temporarily stores the images of the inspection target pattern D and the standard pattern S captured by the re-imaging devices 1a and lb in the image memory 11, and enlarges and reduces the image of the standard pattern S by the enlarging/reducing circuit 12. The image calculation circuit 13 calculates the difference between the enlarged and reduced image of the standard pattern S and the image of the pattern D to be inspected, thereby detecting the difference between the pattern D to be inspected and the standard pattern S. be. In addition, the image calculation circuit 13 also corrects the horizontal direction deviation of both patterns D and S within the field of view of the re-imaging devices 1a and lb prior to the above-mentioned image processing, and these processes are carried out by the control device 4. The image processing controller 14 performs control according to the command.

The width measurement circuit 15 measures the gap width or line width in four directions at 45° intervals including two directions along the edge of the wiring pattern, centering on the portion where the difference found by the image calculation circuit 13 exists, Find the minimum value among them. Then, the image processing controller 14 compares the minimum value of the gap width or line width determined by the width measuring circuit 15 with a predetermined inspection standard to determine whether or not there is a defect.

The image display device 5 displays, for example, a screen containing the defect when a defect is found in the pattern D to be inspected.

As described above, the control device 4 not only gives commands to the image processing controller 14 of the image processing device 10 to perform image processing, but also moves the inspection table 20 to create both patterns D,
In order to move S in the X and Y directions and rotate the turntable 24, a drive signal is issued to each pulse motor drive circuit 32a, 32b, 32c via the pulse motor control circuit 7, and each pulse motor 31a, 31b, 31c, and causes both ring strobes 2a and 2b to emit light via the strobe controller 9 as appropriate in accordance with the accompanying movement of the field of view of the re-imaging device 1a+1b. By driving and controlling a transfer machine (not shown), the pattern D to be inspected is transferred between the production line and the rotary table 24.

The display device 6 draws the entire inspection target pattern D in which defects have been detected using, for example, an X-Y profiler.
It displays the position of the detected defect, its form, etc.

Regarding the operation of the apparatus of the present invention configured as described above, the flowchart of FIG. 4 showing the inspection procedure, the re-imaging apparatus 1a,
Both patterns D within the field of view of lb.

Fig. 5 is an explanatory diagram showing the principle of positional deviation detection of S, and Fig. 4.5 shows the concept of image processing for detecting pattern defects.
The explanation will be given according to the explanatory diagram of the figure.

When starting the inspection, the area around the inspection table 20 is made bright enough to prevent re-imaging by the imaging devices 1a and lb using an appropriate method. The X-direction moving table 2 is moved so that the reference position for correction is the field of view of the re-imaging devices 1a and lb.
2 and the positions of the Y-direction moving table 23 are set.

First, the control device 4 transfers 1! (not shown) via the transfer machine control circuit 8! By driving and controlling the machine, the pattern D to be inspected that has moved along the line is placed at a predetermined position on the rotary table 24. At this time, the imaging device 1a for the pattern D to be inspected
The position in the field of view does not need to be precisely aligned with the position in the field of view of the imaging device 1b for the standard pattern S, and may be a position within the control error of the transfer machine with respect to the reference position.

Next, the patterns D and S are aligned within each field of view of the re-imaging devices 1a and Ib. That is, as shown in FIG. 5(a), the inspection target area D1 where the pattern is actually printed is located in the center of the inspection target pattern D; Sign p2 with two straight lines orthogonally arranged in a predetermined corner outside D1
is printed, and the image of this mark mD2 within the field of view of the imaging device 1a is used as a reference.

5) is an explanatory diagram showing the principle of alignment. As shown by the dashed line, a mark &il! iD
2, it is assumed that the position of the pattern D to be inspected and the position of the standard pattern S match.

Now, the mark 1 of the pattern D to be inspected is within the field of view of the imaging device 1a! ! If D 2 is imaged as shown in FIG. I'll X 1 + X 2 and X
Mark &ill D from a predetermined point X1 directly above the axial outline l
The distance y1 in the Y-axis direction to the image No. 2 is measured.

Note that the distance X In X 2+ 3' I is actually measured by a method such as counting the number of pixels on the image sensor.

When each distance "In X 2+ 3'1" is determined in this way, the image calculation circuit 13 first calculates the visual field outline lx using the following equation (1).

Find the intersection angle θ between ly and mark &Ill D2.

! however,! : When the distance θ between the predetermined points Y1 and Y2 is found,
The image calculation circuit 13 outputs this to the control device 4. The control device 4 issues a control signal to the pulse motor control circuit 7 based on this θΦ value to control the pulse motor 3 via the drive circuit 32a.
1a.

Since the rotary table 24 is rotated by θ by the drive of the pulse motor 31a, the visual field outline lx as shown in FIG. 5(C)
, ly and sign! The X-axis direction part and the Y-axis direction part of ll D 2 are parallel to each other, and the distance XI+"2+71 shown in FIG. 5(a) is X l' + "2', respectively.
+ 3'I' (However, X s' = X
2') *Therefore, the difference between x, l and xg ΔX and Y
The difference Δy between s' and yo is both pattern D.

This is the amount of parallel movement in the X-axis direction and the Y-axis direction, respectively, necessary for correction to make the images of S coincide within the field of view of the re-imaging devices 1a and Ib.

Next, the actual inspection begins. First, from the control device 4 to the pulse motor control circuit 7, the re-imaging devices 1a, lb
Control signals are issued to the pulse motors 31b and 31c so that the field of view becomes the first inspection field of both patterns D and S. As a result, for example, the upper left corner portion of the inspection target area D1 shown in FIG.

Next, the control circuit 4 gives a signal to the pulse motor control circuit 7 to scan the entire inspection target area D1. As a result, the pulse motors 31b and 31c are appropriately driven and stopped at a predetermined speed, and the re-imaging device 1a.

For example, the visual field of lb moves from the upper left corner of the inspection target area D1 shown in FIG. 5(a) to the right edge, moves downward, and then moves to the left edge with a slight overlap. The entire inspection target area D1 is captured by the imaging device 1a.
, lb field of view. During this time, the control device 4 issues an appropriate signal to the strobe controller 9 to cause both strobes 2a and 2b to emit light. Both strobes 2a
, 2b, the re-imaging device 1a,
It is determined based on the drive speed of the pulse motors 31b and 31C, etc. so that each part of the inspection target region D1 of the inspection target pattern D imaged in the field of view tb is sequentially imaged with a predetermined overlap. Therefore, both patterns D and S
Imaging is not performed while the pattern is stopped, but the strobe light is emitted at appropriate intervals while moving both patterns D and S at a constant speed, and images of both patterns D and S are obtained by this strobe light emission. be.

Now, both patterns D are created by the flashes of strobes 2a and 2b.

The predetermined inspection target area of S is imaged by the re-imaging devices 1a and lb, and images DI'1SI) are obtained, respectively. These images Dp and Sp are converted into binarized images Db and Sb, and further a binarized image Db of the pattern D to be inspected among them.
The binary image sb of the 0-order standard pattern S, which has undergone horizontal deviation correction and is temporarily stored in the image memory 11, is enlarged and reduced. This enlargement/reduction process
It is processed by the reduction circuit 12, and FIG. 6 is an explanatory diagram showing the concept thereof.

First, the binarized image sb of the standard pattern S stored in the image memory 11 is sent to the enlargement/reduction circuit 12, and as shown in FIG. 6, the enlarged image S7! and a reduced image Ss are created, and these are transferred again to the image memory 11 and stored therein. The "enlargement/reduction" at this time is different from optical enlargement/reduction in the ordinary sense, and is performed by a method as shown in FIG. That is, for example, as shown in FIG. 7(a)
Regarding the pixel arrangement of the 5 x 5 matrix image sensor in 11) to (55), only the pixel (33) located at the center is "1", and the other pixels are "O", as shown in Fig. 7). Considering the binarized image, enlargement in the present invention is expressed as a logical sum image of each pixel and four pixels on the upper, lower, left and right sides of it, and reduction is expressed as a logical product image. To explain this with reference to the drawings, each pixel (23), (32), (34), (4
Regarding 3), the logical sum with the respective upper, lower, left, and right pixels is "1".

Therefore, the enlarged image of (in FIG. 7) becomes as shown in FIG. 7(C). On the other hand, in FIG. 7(C), the center pixel (33)
Each pixel (23), (32) (34) on the top, bottom, left and right of
, (43), the logical product with the upper, lower, left, and right pixels is 'O''. Therefore, the reduced image of FIG. 7(C) is as shown in FIG. 7(C).

The enlarged image SZ, the reduced image Ss, and the pattern D to be inspected created by the enlargement/reduction circuit 12 in this way are
By determining the difference with the valued image Db, a portion where a difference exists between the pattern D to be inspected and the enlarged image SZ and reduced image Ss of the standard pattern S is determined.

By the way, as shown in pattern D to be inspected shown in Fig. 6, excess gaps in the wiring pattern, such as short-circuited parts, or omissions, such as disconnected conductor parts, clearly cannot be used in practical use. Since it cannot be obtained, it should be judged as defective. However, for example, when the surplus portion is in the shape of a relatively small protrusion and does not short-circuit the gap, as in pattern D to be inspected shown in FIG.
Alternatively, if the missing portion is in a relatively small area and does not reach the extent of breaking the conductive wire portion, it may be considered that there is no quality problem depending on the extent of the missing portion. For this reason, the degree of redundancy or omission is then measured.

First, the width measuring circuit 15 measures the width of the pattern D by several times the designed line width of the pattern D to be inspected, centering on the position where the surplus or omission is detected in the image W1 of the surplus part and the image W2 of the missing part.
In the example of FIG. 1, partial images T1 and T2 are cut out using a square window with a side length of 4 times. Then, if the image W1 is a surplus portion, the width of the gap narrowed by the protruding surplus portion is measured. The measurement of the gap width at this time is 4
The test was carried out in four directions at 5° intervals, and the results are schematically shown in FIG.

FIG. 2(a) shows the gap width measured in the direction of the partial image T1 in FIG. 1, where the high level portion is the gap and the low level portion is the conductor portion. In this direction (■), there is only a slight gap at the tip of the protrusion, and the gap width 2 is the sum of the widths 7!11 and 112 of both sides of the tip of the protrusion.

Thereafter, the gap width 12+l13r14 is calculated in the same manner for each of the directions (2), (2), and (2).

And width I! The surface measurement path 15 has a gap width EI in four directions.
The minimum gap width, in this case I13, is determined from ~7!4 and output to the image processing controller 14.

The image processing controller 14 compares the minimum value 7!3 of the gap width given from the width measurement circuit 15 with the design allowable minimum gap width no. given in advance, and determines that the minimum gap width 13 is the minimum allowable gap. Smaller than width io (/3<
In the case of 1o), it is determined that there is a defect, and the minimum gap width is 1.
3 is the minimum allowable gear tooth width I! If it is equal to or greater than o (J3≧7!o), it is determined that there is no defect.

Note that the width measurement circuit 15 performs exactly the same process on the image W2 of the missing portion, and the result is similarly determined by the image processing controller 14.

Incidentally, in the pattern D to be inspected in FIG. 6, in the case of the image W1 of the surplus portion, if the same processing as described above is performed,
Since the gap width is 0, it is clear that it is determined to be a defect.

In this way, each inspection target pattern D is sequentially inspected, and it is determined whether or not the inspection of the entire inspection target area D1 has been completed, and if the inspection has not been completed, the next inspection field of view is imaged. That is, when the inspection field of view coincides with the field of view of the imaging devices 1a, lb, the strobes 2a, 2b emit light and the same processing as described above is performed.

In this way, imaging of the entire inspection target area and its defect detection are performed sequentially, and if there is a defect in the inspection target pattern D, the entire pattern including the defective part is displayed on the display device 6 such as an X-Y plotter. Drawing is done. Then, a signal is output from the control device 4 to the transfer machine control circuit 8, whereby the pattern D to be inspected is transferred to the line and sent to the next process, and the pattern D to be inspected next is transferred to the rotating table 24. During this time, the control device 4 gives appropriate signals to the pulse motor drive circuit 7 to drive the pulse motor 31.
b and 31c are driven and controlled to return the inspection table 20 to the initial position.

〔effect〕

As detailed above, according to the present invention, the standard pattern that is the inspection standard is enlarged or reduced by pixel-by-pixel logical sum and logical product, and the presence or absence of a defect is determined by finding the difference between this and the pattern to be inspected. Because of this structure, ink bleeding in a screen-printed wiring pattern, fine irregularities at pattern boundaries caused by screen mesh, etc. are not determined to be defects. Further, when changing the inspection standard, it can be easily handled by changing the enlargement/reduction ratio of the image of the standard pattern and changing the minimum reference width of the gap width and line width.

In addition, the angular deviation and horizontal deviation between the pattern to be inspected and the standard pattern are corrected by directly rotating the pattern to be inspected or the standard pattern, or by image processing, so the pattern to be inspected is placed on the inspection table. Strict positioning is not necessary when placing the device, and a distance meter or the like for this purpose is also unnecessary, further improving work efficiency.

In addition, relative movement of both patterns with respect to the imaging device for scanning is done by moving the examination table on which both patterns are fixedly mounted, which is easier and faster than moving both patterns individually. It is.

Furthermore, since the pattern to be inspected and the standard pattern are placed on opposite inspection tables and their images are compared, even if the pattern is changed, it is only necessary to replace the standard pattern that serves as the inspection standard. It can be easily handled, and
Since the image calculation circuit, enlargement/reduction circuit, width measurement circuit, etc. are controlled by the control device, high-speed processing is possible.Differences are detected by pattern comparison inspection, and the gap width is measured again for the portions where the difference is not O. Since the inspection is performed by measuring the line width and comparing it with the minimum allowable width, automatic inspection is possible with high reliability.

In the above embodiment, the angular deviation between the pattern to be inspected and the standard pattern, which is the inspection reference pattern, is corrected by rotating the pattern to be inspected. Alternatively, it is possible to configure it to be performed by image processing,
Furthermore, although the correction of the parallel direction deviation between both patterns is performed by image processing, it may also be performed by moving either the pattern to be inspected or the standard pattern in parallel.

Furthermore, in the above embodiment, the imaging of both patterns is performed by moving the inspection table on which both patterns are placed and emitting strobe light. It may be arranged to stop at a certain position and take an image.

[Brief explanation of the drawing]

Figure 1.2 is a schematic diagram for explaining the present invention in detail, Figure 3 is a block diagram showing the overall configuration of the apparatus of the present invention, and Figure 4 is a schematic diagram for explaining the present invention in detail.
Figure 5 is a flowchart showing the processing procedure, Figure 5 is an explanatory diagram showing the principle of determining angular deviation and horizontal deviation, Figure 6 is an explanatory diagram showing the concept of pattern defect detection method, and Figure 7 is binarization. FIG. 2 is an explanatory diagram showing a method of enlarging/reducing images by logical sum and logical product. la, lb...imaging device 4...control device
10... Image processing device 12... Enlargement/reduction circuit 13... Image calculation circuit 15... Width measurement circuit 20... Inspection table 24... Rotating table 31a, 31
b, 31c...Pulse motor D...Inspection standard pattern S...Standard pattern SZ...Enlarged image of standard pattern Ss...Reduced image of standard pattern Figure 4 (a) (b)
CC) Figure 7 (a) (b) Figure b (C)

Claims (1)

[Claims] 1. Imaging an inspection reference pattern and a pattern to be inspected, enlarging or reducing the image of one of the two patterns to a size corresponding to the determination criterion, and imaging one of the enlarged and reduced images. Find the difference between the image of one pattern and the image of the other pattern, measure the pattern line width or gap width between lines for areas where the difference is not 0, and use the measured line width and gap width as the inspection standard. A pattern inspection method characterized in that defects in the pattern to be inspected are detected by comparison. 2. A movable inspection table on which an inspection standard pattern and a pattern to be inspected are placed; two imaging devices that capture images of the two patterns; and correction of angular and horizontal deviations between the two patterns. an enlargement/reduction circuit for creating enlarged and reduced images of the inspection reference pattern imaged by the imaging device; an image calculation circuit that detects a difference between an image and an image of the pattern to be inspected taken by the imaging device; and a line of the pattern where the difference between the two patterns detected by the image calculation circuit is not 0. It is characterized by comprising a width measuring circuit that measures the width or the gap width between lines, and an arithmetic circuit that detects defects in the pattern to be inspected by comparing the detection result of the width measuring circuit with a reference value. pattern inspection equipment.