JPH07326563A - Exposure condition evaluating pattern, and method and system for evaluating exposure condition using the same - Google Patents

Abstract

PURPOSE:To compute an optimum exposure focusing surface and an optimum exposure amount and control exposure processing conditions of an exposure system by a method wherein the minimum interval between a concave pattern and a convex pattern of a resist image of a pattern for evaluating exposure conditions formed on a wafer is detected. CONSTITUTION:A pattern 1 for evaluating exposure conditions is formed with a plurality of opposing wedge-shaped patterns and comprises a pattern 1a and a pattern 1b. In the pattern 1a, opposing wedge-shaped patterns are formed with a concave pattern (removing pattern) and a convex pattern (leaving pattern) arranged in a horizontal (X) direction and a vertical (Y) direction at intervals of boundary resolution degree of an exposure system. On the other hand, the pattern 1b is formed with a concave pattern and a convex pattern arranged in horizontal and vertical directions in the same manner at intervals which are about double as wide as the boundary resolution degree of the exposure system. Accordingly, intervals between the exposed concave and convex patterns to be processed are measured, whereby an optimum exposure focusing surface can be computed from the mean value of the both and an optimum exposure amount can be computed from the difference of the both.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern formed on a mask used in a photolithography process in a manufacturing process of a semiconductor integrated circuit, and an exposure condition evaluation method and apparatus using the pattern, In particular, the present invention relates to an exposure condition evaluation pattern suitable for calculating the optimum exposure condition at high speed and with high accuracy and suitable for shortening the setup time of the exposure apparatus, and an exposure condition evaluation method and apparatus using the same.

[0002]

2. Description of the Related Art In a photolithography process (hereinafter referred to as a photolithography process) in the manufacture of a semiconductor integrated circuit, a circuit pattern drawn on a mask (reticle) by a reduction projection exposure apparatus is mainly formed on a photosensitive substrate (via a projection lens). (Hereinafter, referred to as wafer), and a circuit pattern is formed on the wafer. During this transfer, the height and tilt of the wafer are adjusted by detecting the optimum image forming surface of the projection lens so that the wafer is accurately set on the optimum image forming surface of the projection lens. If it is correct, the projected image of the reticle pattern is not accurately formed on the wafer, and a blurred pattern is formed on the wafer, which causes a problem of poor resolution.

On the other hand, if the exposure time (exposure amount) for each shot is not set accurately, a deviation occurs between the line width of the circuit pattern formed on the wafer and the designed line width, and finally the desired characteristics are obtained. Will not be satisfied. As described above, when forming a pattern with the exposure apparatus, unless the exposure conditions such as the optimum exposure focal plane position of the projection lens and the optimum exposure amount are accurately set, there is a problem that the yield and the like decrease.

Therefore, in the prior art, first, one wafer is used in advance while changing at least one of the wafer height and the exposure amount, which are exposure conditions, for each shot, for example, from the minimum line width of the circuit pattern. A reference pattern made up of a plurality of rectangular marks having different line widths including thin marks is sequentially transferred and exposed on the wafer. Then, the line width of the reference resist pattern image formed in a matrix on this wafer,
Alternatively, the pattern length is detected by a scanning electron microscope,
The optimum exposure focal plane and the optimum exposure amount of the projection lens are calculated from the minimum line width of the resist pattern image resolved on the wafer.

[0005]

However, in the method of detecting the line width using the above scanning electron microscope, the apparatus itself is expensive, and exhaustion or the like is required when the wafer is mounted. Was needed. Furthermore, in any of the above methods, since the line width or pattern length of the resist pattern image formed in a matrix on the wafer is detected while changing the exposure conditions for the reference pattern,
There is also a problem that it takes time to calculate the optimum exposure condition.

The present invention has been made in view of the above problems of the prior art.
The optimum exposure conditions can be calculated at high speed and high accuracy,
An object of the present invention is to provide an exposure condition evaluation pattern capable of shortening the setup time of the exposure apparatus, and an exposure condition evaluation method and apparatus using the pattern.

[0007]

To achieve the above object, the present invention is intended to measure appropriate exposure conditions of an exposure apparatus when the circuit pattern is transferred onto the wafer through the projection lens by the exposure apparatus. In addition, the reticle has a reference pattern for exposure condition evaluation, which is formed by a concave pattern and a convex pattern with the same shape, and the resolution of the pattern width is almost the same as the limit line width that can be resolved by the projection lens. The line width is about twice the limit.

Further, when the circuit pattern is transferred onto the wafer by the exposure apparatus through the projection lens, the pattern is transferred in the apparatus which measures the proper exposure condition of the exposure apparatus by using the reticle having the pattern. A wafer stage that holds a wafer, a system that generates a video signal of a resist image on the wafer held on the wafer stage, a video signal that is output from this system, and the interval and concave pattern of the concave pattern of the resist image And a pattern detection device having an image signal processing circuit that generates the detection result as formation information of the resist image, and based on the formation information from the pattern detection device, the projection lens is set as the optimum exposure condition of the exposure device. The optimum exposure focal plane and the optimum exposure amount are calculated, and the exposure processing of the exposure apparatus is performed according to the optimum exposure conditions. Providing a control device for controlling the matter.

[0009]

With the above structure, a reticle having a desired exposure condition evaluation pattern is used, and this pattern is transferred and exposed onto a wafer to form a resist pattern image of the exposure condition evaluation pattern formed on the wafer. By detecting the minimum distance between the concave pattern and the convex pattern, it is possible to calculate the optimum exposure focal plane and the optimum exposure amount, and control the exposure processing condition of the exposure apparatus based on the optimum exposure condition. Therefore, the number of times of detecting the line width can be reduced, the optimum exposure condition can be calculated with high accuracy and high speed, and the offset amount in the exposure apparatus can be corrected in a short time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the exposure condition evaluation pattern of the present invention will be described below with reference to FIGS. Figure 1
2 is a diagram showing an exposure condition evaluation pattern having opposing wedge-shaped patterns, FIG. 2 is an enlarged view showing the intervals between the concave and convex patterns of the opposing wedge-shaped patterns of FIG. 1 and their detection signals, and FIG. 2 shows the relationship between the concave and convex pattern widths and the focus in various exposure amounts, FIG. 4 shows the relationship between the average value of the concave and convex pattern widths in FIG. 2 and the focus, and FIG. 6 is a diagram showing the relationship between the concave and convex pattern widths and the exposure amount, FIG. 6 is a diagram showing the relationship between the average value and difference value of the concave and convex pattern widths in FIG. 2 and the exposure amount, and FIG. It is a figure which shows the relationship between the pattern width of the concave and convex below an image limit, and a focus.

In FIG. 1, reference numeral 1 is an exposure condition evaluation pattern formed of a plurality of opposed wedge-shaped patterns.
It is composed of two sets of a pattern 1a and a pattern 1b. The pattern 1a is formed by opposing wedge-shaped patterns, which are a blank pattern (concave pattern) and a remaining pattern (convex pattern) arranged on the left and right (X direction) and on the upper and lower sides (Y direction) at intervals of the limit resolution of the exposure apparatus. , On the other hand, pattern 1
The pattern b is formed by a blank pattern and a remaining pattern which are arranged on the left and right sides and on the upper and lower sides at intervals of about twice the limit resolution of the exposure apparatus. Here, the pattern 1a is used for focus position (exposure focal plane) detection, and the pattern 1b is used for exposure amount evaluation.

When an exposure condition evaluation pattern consisting of opposed wedge-shaped concave and convex patterns as shown in FIG. 1 is used, first, the exposure amount is fixed and the focus position is changed to perform exposure. Next, contrary to the above, the focus position is fixed and the exposure amount is changed to perform exposure. After developing the concave and convex wedge-shaped patterns thus formed, the line width of the narrowed portion which is opposed to each other is measured for the concave pattern as shown in FIG. As for the convex pattern, as shown in FIG. 2 (b), the minimum facing distance is measured. 2A and 2B are observation patterns of the blank pattern width a and the remaining pattern width b under an optical microscope based on the detection signals in the cross section AA 'of the concave pattern and the cross section BB' of the convex pattern.

To measure the focus position, that is, to detect the focus position, the minimum interval between the concave and convex patterns is
The pattern 1a formed at the resolution limit is used. Distance between this focus position and the concave pattern (width of the removed pattern)
, And there is a relationship approximated to a quadratic function as shown in FIG. 3A, and the extraction pattern width a becomes the minimum at the best focus position. Further, this curve varies depending on the exposure amount, and the coefficient of the quadratic term increases as the exposure amount increases. On the other hand, between the focus position and the interval between the convex patterns (remaining pattern width), similarly, as shown in FIG.
There is a relationship that is approximated by a quadratic function, and the curve differs depending on the exposure amount. The larger the exposure amount, the smaller the coefficient of the quadratic term.

However, as shown in FIG. 4, the interval between the concave pattern and the convex pattern, that is, the average value of each of the pattern widths of the blank pattern and the remaining pattern has the same quadratic curve regardless of the exposure amount. Therefore, if the exposure amount is set first and the focal position is changed to measure the intervals of the concave and convex patterns after exposure, the optimum exposure focal plane can be obtained by quadratic approximation.

Next, for the setting of the exposure amount, the pattern 1b in which the minimum interval of the concave or convex pattern is formed to be about twice the resolution limit is used. There is a monotonically decreasing relationship as shown in FIG. 5A between the exposure amount and the interval between the concave patterns (the width of the removed pattern), and on the other hand, between the interval between the convex patterns (the width of the remaining pattern). Similarly has a monotonically increasing relationship as shown in FIG. The relationship of this change differs depending on the focus position, but the difference between the concave pattern interval and the convex pattern interval has linearity as shown in FIG. Therefore, if the pattern interval when formed with the optimum exposure amount is measured in advance, the focus position is set, and after the exposure is performed while changing the exposure amount, the difference between the concave pattern interval and the convex pattern interval is measured and measured in advance. By comparing with the pattern interval, the optimum exposure amount is obtained from the linear approximation result shown in FIG.

Further, in advance, by using the exposure condition evaluation pattern as shown in FIG. 1, the average value of the intervals between the focus position and the uneven pattern shown in FIG. 4, and the exposure amount and the interval between the uneven patterns shown in FIG. If the relationship of the difference is obtained, the average value of the exposed pattern width and the difference value are obtained for the wafer exposed under a certain exposure condition, and the average value of the obtained pattern width and the optimum focus position An offset amount from the optimum focus position and an offset amount from the optimum exposure amount are compared by respectively comparing the average value of the pattern width and the obtained difference value of the pattern width and the difference in the optimum exposure amount. Are required respectively. The exposure apparatus can be stabilized by feeding back each offset amount to the exposure apparatus.

Further, as shown in FIG. 3 and FIG.
The curves showing the relationship between the concave and convex pattern widths (outer pattern width) and the convex pattern width (remaining pattern width) and the focus, and the relationship between the average of both the unremoved pattern width and the remaining pattern width and the focus are in the positive and negative range of the focus. Since it is almost symmetrical, it is difficult to determine whether it is positive or negative. However, if a pattern less than the resolution limit shown in FIG. 7 is used, the shape of the curve is different in the positive and negative focus ranges as shown in FIG. 7, and this is used to determine whether the focus position is positive or negative, that is, the focus position determination. Can be easily performed.

Next, the exposure condition evaluation apparatus of the present invention is shown in FIG.
Will be described with reference to. FIG. 8 is a schematic diagram of an exposure condition evaluation apparatus.

In FIG. 8, the illumination σ of the light emitted from the illumination light source 6 is determined by the aperture stop 7, and the illumination field is determined by the field stop 8. The light passing through these passes through the lens 9, is reflected by the beam splitter 10, passes through the objective lens 11, and is exposed on the wafer 12 mounted on the stage 13 as shown in FIG. The condition evaluation pattern 1 is irradiated. The light reflected by the exposure condition evaluation pattern 1 on the wafer 12 is reflected by the objective lens 11,
After passing through the beam splitter 10 and the imaging lens 14, a pattern image is formed on the two-dimensional sensor 15. The image of this pattern is taken into the image processing unit 16, and the image calculation unit 17
The distance between the wedge-shaped concave and convex patterns facing each other is measured by. The average (a / 2 +) of the pattern widths a and b of the blank pattern and the remaining pattern measured here
b / 2) and the difference (ab), the relationship data between the focus shown in FIG. 4 and the average of the removed pattern width and the remaining pattern width, which are stored in the exposure condition evaluation database 18, and shown in FIG. It is compared with the relationship data of the difference between the exposure amount, the removed pattern width and the remaining pattern width, and the matching focus position and exposure amount are calculated. The focus position and the exposure amount calculated here are sent to the parameter setting unit 20 of the exposure apparatus 19 and compared with the initially set parameter. The difference (deviation amount) is added to the initially set parameter, and the difference is added. The parameter is set as a new parameter, and the subsequent exposure is performed.

As a result, the offset amount of the exposure device 19 can be measured easily and at high speed and with high accuracy, preferable exposure conditions can be set, and a stable line width can be obtained. At the same time, the setup time of the exposure device 19 can be shortened.

FIG. 9 shows a second embodiment of the exposure condition evaluation pattern of the present invention. As shown in the figure, the exposure condition evaluation pattern 1'of this embodiment is the pattern 1 shown in FIG.
Pattern 1 formed below the limit resolution of the exposure apparatus
c is added. With this pattern 1c, it is possible to easily determine whether the focus position is in the plus range or the minus range as described with reference to FIG.

FIG. 10 shows a third embodiment of the exposure condition evaluation pattern of the present invention. As shown in the figure, this exposure condition evaluation pattern 2 is composed of three sets of patterns 2a, 2b and 2c. In the pattern 2a, a diamond-shaped pattern is formed vertically and horizontally at intervals of the limit resolution of the exposure apparatus.
Formed by the remaining pattern and the blank pattern arranged
The pattern 2b is formed by a remaining pattern and a blank pattern which are arranged at four times in the vertical and horizontal directions at intervals of about twice the limit resolution of the exposure apparatus, and the pattern 2c is arranged in four vertically and horizontally at intervals below the critical resolution of the exposure apparatus. It is formed by the left pattern and the removed pattern. When this pattern 2 is used, the pattern intervals facing each other in the x and y directions are CC ′,
Since it is measured at each of two locations, DD ′, EE ′, and FF ′, it has the effect of improving the interval measurement accuracy.

FIG. 11 shows a fourth embodiment of the exposure condition evaluation pattern of the present invention. As shown in the figure, this exposure condition evaluation pattern 3 has a pattern interval facing each other which is about twice the limit resolution of the exposure apparatus and a limit resolution.
Those having a resolution less than or equal to the limit resolution are constituted by a remaining pattern 3a and a blanking pattern 3b which are arranged in a stepwise manner. When this pattern 3 is used, three types of patterns having different intervals can be formed into one pattern, so that the exposure condition evaluation pattern 3 can be miniaturized.

FIG. 12 shows the fifth embodiment of the exposure condition evaluation pattern of the present invention. As shown in the figure, the exposure condition evaluation pattern 4 includes a blank pattern and a remaining pattern 4a whose pattern intervals are composed of lines and spaces at the limit resolution of the exposure apparatus, and a blank pattern and a remaining pattern 4b about twice the limit resolution. , And the remaining pattern 4c. When this pattern is used, the pattern formation is the same as that used in the circuit portion of the substrate, and thus it has an effect of facilitating production.

In FIGS. 1, 9, 11, and 12, the patterns are arranged on the left and right (X direction) and on the top and bottom (Y direction) in each set. It may be one of the X direction) and the top and bottom (Y direction).

FIG. 13 is a diagram showing a specific example of an exposure apparatus equipped with the exposure condition evaluation apparatus of the present invention. In the figure, the same reference numerals as those in FIG. 8 indicate the same elements. In the figure, exposure light emitted from an illumination system 29 passes through a shutter 30 and reduces a pattern drawn on a reticle 31 by a reduction lens 32.
Reduced projection exposure is performed on the wafer 12 via. Wafer 12
The upper exposure position is controlled by the stage 13. Reference numerals 29 to 32, 38 and 39 are reference numerals 1 shown in FIG.
It is an exposure apparatus corresponding to 9. The wafer 12 exposed by such an exposure apparatus is mounted on this exposure apparatus again after being developed, and the exposure condition evaluation optical system 33 measures the interval between the removal and the leaving of the exposure condition evaluation pattern. The exposure condition evaluation optical system 33 includes the reference numerals 6 to 11 and 14 shown in FIG.
It is the same as the optical system consisting of 15 and 15.

As for the light emitted from the illumination light source 6 of the exposure condition evaluation optical system 33, the illumination .sigma. Is determined by the aperture stop 7 and the illumination field is determined by the field stop 8 as in the case of FIG. . The light that has passed these passes through the lens 9, the beam splitter 10, and the objective lens 11, and is formed on the wafer 12 mounted on the stage 13 and the exposure condition evaluation pattern 1 as shown in FIG. Is irradiated. The light reflected by the exposure condition evaluation pattern 1 on the wafer 12 passes through the objective lens 11, the beam splitter 10, and the imaging lens 14 to form a pattern image on the two-dimensional sensor 15. The image of this pattern is taken into the image processing unit 34, and the interval between the wedge-shaped concave pattern and convex pattern facing each other is measured by the image calculation unit 35. Each pattern width a of the blank pattern and the remaining pattern measured here,
Regarding the average (a / 2 + b / 2) and the difference (ab) of b, the relationship data between the focus shown in FIG. 4 and the average of the removal pattern width and the remaining pattern width stored in the exposure condition evaluation database 36. , And the corresponding focus position and exposure amount are calculated by comparing with the relationship data of the difference between the exposure amount and the removal pattern width and the remaining pattern width shown in FIG. The focus position and the exposure amount calculated here are sent to the parameter setting unit 37, compared with the initially set parameter, the difference (deviation amount) is added to the initially set parameter, and the parameter to which the difference is added is newly updated. Set as a parameter. The reference numerals 34 to 37 have the same functions as the reference numerals 16 to 18 and 20 shown in FIG.

The shutter opening / closing time control unit 38 controls the exposure amount to a desired exposure time, while the stage control unit 39 controls the exposure focus position with respect to the focus position for subsequent exposure. As a result, as in the case of FIG. 8, the offset amount of the exposure apparatus can be measured simply and at high speed, preferable exposure conditions can be set, and a stable line width can be obtained.

Next, FIG. 14 is a diagram showing an example of a photolithography process stabilization system in which the exposure condition evaluation apparatus of the present invention is used. In the figure, the same reference numerals as those in FIG. 8 indicate the same elements. In the figure, the pattern interval measured by the exposure condition evaluation device 41 is feedback controlled by resetting each parameter to a new parameter for the exposure device 19 and the developing device 40 by the photolithography process control unit 43, and With respect to the etching apparatus 42, feedforward control is performed by resetting each parameter to a new parameter. With this, the focus of the exposure apparatus and the exposure amount offset amount are obtained, and the process conditions such as the offset amount of the exposure apparatus, the development time of the developing apparatus, and the etching time of the etching apparatus are set and controlled from these values. Therefore, it is possible to stabilize the pattern formed on the wafer after etching.

FIG. 15 is a diagram showing another example of a photolithography process stabilization system in which the exposure condition evaluation apparatus of the present invention is used,
FIG. 16 is a diagram showing the light transmittance of the exposed and unexposed portions of the resist. In the figure, the same reference numerals as those in FIGS. As shown in FIG. 16, the exposed portion 47 and the unexposed portion 48 of the resist 46 on the substrate 45 have different substances and different transmittances. Therefore, the exposure apparatus 1 shown in FIG.
When light near the exposure wavelength is used as illumination light in the exposure condition evaluation device 41 between the developing device 40 and the developing device 40, the exposure condition evaluation pattern image is detected, and the above-mentioned blanking and remaining pattern width is measured. From the pattern width information measured before the development and the pattern width information measured by the exposure condition evaluation device 41 between the developing device 40 and the etching device 42, the photolithography process control unit 44 controls the exposure device 19, the developing device. By setting the parameters for each of 40 and the etching device 42 and operating under these conditions, it becomes possible to obtain a wafer having a stable pattern shape as in the case of the above-mentioned 14.

[0031]

As described above, according to the present invention, by measuring the distance between the exposed concave and convex patterns, the optimum exposure focal plane can be determined from the average value of the two. Further, since the optimum exposure amount can be calculated from the difference between the two, the optimum exposure condition can be calculated at high speed and with high accuracy, and the setup time of the exposure apparatus can be shortened.

[Brief description of drawings]

FIG. 1 is a diagram showing an opposing wedge-shaped pattern shape of a first embodiment of an exposure condition evaluation pattern of the present invention.

FIG. 2 is an enlarged view showing an interval between concave and convex patterns of the wedge-shaped pattern facing each other in FIG. 1 and a detection signal thereof.

FIG. 3 is a diagram showing the relationship between the concave and convex pattern widths in FIG. 2 and the focus at various exposure amounts.

FIG. 4 is a diagram showing the relationship between the average value of the concave and convex pattern widths of FIG. 2 and focus.

5 is a diagram showing the relationship between the concave and convex pattern widths of FIG. 2 and the exposure dose.

FIG. 6 is a diagram showing the relationship between the average value and difference value of the concave and convex pattern widths of FIG. 2 and the exposure amount.

FIG. 7 is a diagram showing the relationship between concave and convex pattern widths below the resolution limit and focus.

FIG. 8 is a schematic diagram of an exposure condition evaluation apparatus.

FIG. 9 is a diagram showing a second embodiment of the exposure condition evaluation pattern of the present invention in which a pattern having an interval equal to or less than the limit resolution is added to the pattern of the first embodiment.

FIG. 10 is a third example of the exposure condition evaluation pattern of the present invention.

FIG. 11 is a fourth example of the exposure condition evaluation pattern of the present invention.

FIG. 12 is a fifth example of the exposure condition evaluation pattern of the present invention.

FIG. 13 is a diagram showing a specific example of an exposure apparatus equipped with the exposure condition evaluation apparatus of the present invention.

FIG. 14 is a diagram showing an example of a photolithography process stabilization system in which the exposure condition evaluation apparatus of the present invention is used.

FIG. 15 is a diagram showing another example of a photolithography process stabilization system in which the exposure condition evaluation apparatus of the present invention is used.

FIG. 16 is a diagram showing light transmittance between an exposed portion and an unexposed portion of a resist.

[Explanation of symbols]

1, 1 ', 2, 3, 4 ... Exposure condition evaluation pattern, 1
a, 2a, 4a ... Limit resolution interval pattern, 1b, 2
b, 4b ... Approximately twice the limit resolution interval pattern, 1c, 2
c, 4c ... Patterns less than the limit resolution, 6 ... Illumination light source, 7 ... Aperture stop, 8 ... Field stop, 9 ... Lens, 10 ...
Beam splitter, 11 ... Objective lens, 12 ... Wafer,
Reference numeral 13 ... Stage, 14 ... Image forming lens, 15 ... Two-dimensional sensor, 16 ... Image processing section, 17 ... Image computing section, 18 ... Exposure condition evaluation database, 19 ... Exposure device, 20 ... Parameter. Setting unit, 40 ... developing device, 41 ... exposure condition evaluation device, 42 ... etching device, 43, 44 ... photolithography process control unit, 46 ... resist, 47 ... resist exposure unit, 4
8 ... Unexposed portion of resist.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G21K 5/02 X H01L 21/66 J 7630-4M (72) Inventor Masahiro Watanabe Totsuka, Yokohama, Kanagawa Prefecture 292, Yoshida-cho, Tokyo, Ltd., Production Engineering Laboratory, Hitachi, Ltd. (72) Inventor Susumu Komoritani 5-20-1, Kamisuihonmachi, Kodaira-shi, Tokyo Within Hitachi, Ltd. Semiconductor Division

Claims (9)

[Claims] 1. A pattern for exposure condition evaluation in an exposure apparatus for projecting and exposing a circuit pattern on a reticle onto a photosensitive substrate, wherein straight lines arranged facing each other with a pattern width of a limit resolution of the exposure apparatus. And a concave pattern and a convex pattern having the same pattern and having the pattern width of approximately twice the limit resolution of the exposure apparatus and facing each other. The exposure condition evaluation pattern to be. 2. A pattern for exposure condition evaluation in an exposure apparatus for projecting and exposing a circuit pattern on a reticle onto a photosensitive substrate, wherein straight lines arranged facing each other with a pattern width of a limit resolution of the exposure apparatus. A concave pattern and a convex pattern, and a concave pattern and a convex pattern of the same figure that are arranged to face each other with a pattern width that is approximately twice the limit resolution of the exposure apparatus.
An exposure condition evaluation pattern comprising three sets of the figure and a concave pattern and a convex pattern of the same figure, which are arranged to face each other with a pattern width equal to or less than the limit resolution of the exposure apparatus. 3. The exposure condition evaluation pattern according to claim 1, wherein the figures of the concave pattern and the convex pattern are formed in a wedge shape or a diamond shape. 4. A pattern for exposure condition evaluation in an exposure device for projecting and exposing a circuit pattern on a reticle onto a photosensitive substrate, wherein the pattern intervals facing each other are about twice the limit resolution of the exposure device, the limit resolution and the limit resolution. An exposure condition evaluation comprising two sets of a concave pattern having the following pattern widths arranged stepwise and a convex pattern having the same pattern as the concave pattern having the pattern widths arranged stepwise. pattern. 5. The concave pattern and the convex pattern of each set have a pattern in the left-right direction (X direction) and in the vertical direction (Y direction).
Direction), the exposure condition evaluation pattern according to claim 1, 2, or 4. 6. An exposure condition evaluation method in an exposure apparatus for projecting and exposing a circuit pattern on a reticle onto a photosensitive substrate, wherein an exposure condition evaluation pattern having at least two sets of concave and convex patterns having different pattern widths is used. Then, in advance, data showing the relationship between the average value of the concave and convex pattern widths and the focus and data showing the relationship between the value of the difference between the concave and convex pattern widths and the exposure amount were obtained, and obtained. An exposure condition characterized in that each data is compared with an average value and a difference value of a pattern width of a wafer exposed under an arbitrary exposure condition, and an offset amount between the optimum exposure focal plane and the optimum exposure amount is obtained. Evaluation methods. 7. The exposure condition evaluation pattern is composed of three sets of straight line patterns arranged opposite to each other having a pattern width of a limit resolution of an exposure apparatus, a pattern width of almost twice the limit resolution and a pattern width of the limit resolution or less. The optimum exposure focal plane is obtained from the pattern having the limit resolution, the optimum exposure amount is obtained from the pattern having almost twice the limit resolution, and whether the focus position is positive or negative is determined to be not more than the limit resolution. The exposure condition evaluation method according to claim 6, wherein the exposure condition evaluation method comprises a pattern. 8. The optimum distance between the patterns of concavities and convexities exposed on the wafer is measured before development by using wavelengths having different resist transmittances between an exposed portion and an unexposed portion. The exposure condition evaluation method according to claim 6, wherein the exposure focal plane and the optimum exposure amount are calculated. 9. A means for measuring the distance between the patterns of concavities and convexities formed on the wafer, a means for obtaining the average and the difference between the intervals of the patterns of concavities and convexes facing each other from the measurement result, and a focus and an exposure amount. And an exposure condition evaluation device which feeds back the offset amount to the exposure device.