TW201932977A - Pattern writing method, method of manufacturing a photomask, and method of manufacturing a device for a display apparatus - Google Patents

Abstract

To provide a method of transferring, on a transfer object, a pattern having a CD accuracy exactly as designed. This invention provides a pattern writing method and techniques related thereto. The pattern writing method is for providing a photomask with a transfer pattern for manufacture of a device for a display apparatus by writing a pattern on a photomask substrate on the basis of predetermined designed pattern data. The method uses a writing device for writing the pattern on the photomask substrate by energy beams and includes a beam intensity correction map forming step and a writing step. In the beam intensity correction map forming step, when a CD error with respect to a designed value is caused due to a manufacturing step of the device for the display apparatus, a beam intensity correction map for correcting the CD error is prepared based on a preliminarily-acquired tendency of occurrence of the CD error, including a position of the CD error and an error amount. In the writing step, pattern writing is carried out by the writing device using the beam intensity correction map together with the designed pattern data.

Description

Pattern drawing method, method of manufacturing photomask, and method of manufacturing device for display device

The present invention relates to a pattern drawing method for obtaining a photomask for manufacturing an electronic component, and more particularly to a photomask suitable for manufacturing an element for a display device (FPD, Flat Panel Display).

Patent Document 1 (hereinafter referred to as Document 1) describes a method of correcting a mask for a color filter. According to the document 1, the following method for correcting the mask: obtaining a map of the change in the amount of change with respect to the design value due to the process characteristics of the color filter by the line width and the coordinates, and the initial design value When the amount of change is corrected, the correction is performed from a region where the change in the short-sized correction region is large to a region where the change is small. In the correction method, the correction region is obtained from the vicinity of the boundary portion between the correction region and the adjacent region to be corrected. In the adjacent area, the correction value is distributed and randomly distributed in stages and randomly. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 5254068

[The problem that the invention wants to solve]

In recent years, in the industry of liquid crystal display devices or display devices including organic EL (Electro Luminescence) displays, there is a strong demand for image refinement and high integration, and it is expected to be bright, save power, and improve. The so-called high-speed display, wide viewing angle display performance. With the demand for such high definition, a reticle pattern used for manufacturing a display device element (meaning a component constituting a display device or a part thereof, hereinafter, simply referred to as a display device) is patterned. The tendency to be more refined is also becoming more pronounced. For example, a TFT (Thin Film Transistor) layer used in a liquid crystal display device or an organic EL display device, or a black matrix (BM, Black Matrix) or a light spacer (PS, used to form a color filter). In terms of the layer of Photo Spacer), a method of transferring a fine pattern under the correct CD (Critical Dimension, which is also used as the width of the pattern) as well as the design is also sought.

For example, in the thin film transistor used in the above display device, it is required that the contact hole formed in the interlayer insulating film has a diameter of 3 μm or less (for example, 1.5 to 3 μm or the like), or the width of the color filter BM is A fine pattern such as 8 μm or less (for example, 3 to 8 μm, etc.). It is desirable to be able to finely perform such a fine hole pattern, dot pattern, line pattern, and space pattern formation.

In addition, in the case of manufacturing a display device, in addition to the case where a photoresist film to be an etching mask is formed on a transfer target (display panel substrate or the like) of a transfer pattern of a transfer mask, in many cases, A photosensitive resin film which is a part of the structure as a component is formed. In this case, the deviation (CD error) of the CD from the design value is not only an error in the pattern width, but also a shape error such as the height of the three-dimensional structure formed by the transfer pattern, and thus the action of the final product may be caused. Performance has an impact. Based on this consideration, it is important to minimize the deviation of the CD from the design value.

In order to obtain high resolution in the field of photomasks for manufacturing semiconductor devices (LSI, Large Scale Integration) in which the degree of integration is high and the pattern is remarkably advanced compared with the display device. It is recommended to apply an optical system having a high numerical aperture NA (for example, more than 0.2) to the exposure apparatus and to shorten the wavelength of exposure light. As a result, excimer lasers of KrF or ArF (a single wavelength of 248 nm and 193 nm, respectively) are used in this field. An EB (Electron Beam) drawing device is also used for the drawing device for manufacturing the photomask.

On the other hand, in the field of lithography technology for manufacturing display devices, the above-described methods are generally not applied to improve the resolution. For example, an exposure apparatus used in the field has an optical system having an NA (numerical aperture) of about 0.08 to 0.2. Moreover, the exposure light is also mostly used i-line, h-line, or g-line, and is obtained by irradiating a large area by using a wide-wavelength light source mainly containing the same (for example, one side of the main surface is 300 to 2000 mm). The amount of light in the quadrilateral is strongly inclined to focus on production efficiency and cost.

In this case, when the display device is manufactured recently, as described above, the refinement of the pattern is required to be improved. Therefore, when manufacturing the display device, a technique is sought in which the exposure of the exposure device as described above is applied. Conditions, and even for large areas can transfer the same pattern as the design.

Document 1 is completed in the following context: In recent years, high image quality and brightness improvement of liquid crystal displays and the like have been desired, and a black matrix of color filters has been sought in order to increase the number of pixels and increase the light transmittance. Thin line. Document 1 also raises the problem that in the process of using the lithography of the photomask, the pattern of the pattern or the inherent characteristics of the etching apparatus may cause errors in the pattern after drawing and development, compared with the design data. For such a problem, in Document 1, a method of improving the local size error in the mask process of the color filter is proposed.

However, according to the study by the inventors, it has been found that the correction of the CD error generated in the manufacturing steps of the display device is still insufficient in the method described in the literature 1.

Therefore, the inventors of the present invention have intensively studied in order to avoid the above-described defects and to provide a method of transferring a pattern having the same CD precision as that of a design onto a transfer target, and have completed the present invention. [Technical means to solve the problem]

(First aspect) A pattern drawing method for drawing on a photomask substrate using a drawing device based on specific design pattern data, thereby forming a photomask including a transfer pattern for manufacturing an element for a display device The pattern drawing method includes the following steps: a beam intensity correction map forming step of including the CD error based on a pre-mastered when a CD error is generated with respect to a design value due to the manufacturing step of the display device component a positional and error amount of the CD error occurrence tendency information forming a beam intensity correction map for correcting the CD error; and a drawing step of using the beam intensity correction map together with the design pattern data, and The drawing device described above is depicted. (Second aspect) The second aspect of the present invention is the pattern drawing method according to the first aspect, wherein the manufacturing step of the display device element includes an exposure step of exposing the photomask by an exposure device, and the CD The error is an error due to the exposure conditions of the above exposure apparatus. (Third aspect) The third aspect of the present invention is the pattern drawing method of the second aspect, wherein the exposure device is a projection exposure method, and the projection exposure mode is performed by scanning a plurality of lenses. The transfer pattern is transferred onto the transfer target. (Fourth Aspect) The fourth aspect of the present invention is the pattern drawing method according to the second aspect described above, wherein the exposure apparatus is applied to a proximity exposure method. (5th aspect) The fifth aspect of the present invention is the pattern drawing method according to any one of the first to fourth aspects, wherein the transfer pattern includes a repeating pattern in which a plurality of unit patterns are regularly arranged. . (Sixth Aspect) The sixth aspect of the present invention is the pattern drawing method according to any one of the first to fifth aspects described above, wherein in the drawing step, the multiple drawing is performed. (Seventh Aspect) A seventh aspect of the present invention provides a method of producing a photomask, comprising: the drawing step described in any of the first to sixth aspects. (Eighth Aspect) The eighth aspect of the present invention provides a method of manufacturing a device for a display device, comprising: a step of preparing a photomask formed by the manufacturing method described in the seventh aspect, and projecting by application The exposure apparatus of the exposure method transfers the transfer pattern onto the transfer target, and the projection exposure method transfers the transfer pattern of the photomask to the transfer target by scanning a plurality of lenses. (9th aspect) A ninth aspect of the invention is a method of manufacturing a device for a display device, comprising: a step of preparing a photomask formed by the manufacturing method described in the seventh aspect, and applying the same In the exposure apparatus of the exposure mode, the transfer pattern is transferred onto the transfer target. [Effects of the Invention]

According to the present invention, the CD error of the pattern generated in the manufacturing steps of the display device can be surely and effectively corrected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. At the time of manufacturing a display device, a high-precision photomask manufacturing technique is sought, which is capable of stably forming a highly difficult transfer pattern including a pattern having a small CD as well as a design value. On the other hand, even if a mask having a CD accuracy according to such a mask manufacturing technique and having no problem is used, it is formed on the object to be transferred (display panel substrate, etc.) by exposing it to light. The size of the transferred image varies from the target, and there are several factors that cause CD errors.

For example, before the exposure, the film thickness of the photoresist film formed on the transfer target may be distributed in-plane (non-uniformity), or during the development, the supply of the developer may be changed in-plane. In the surface on the object to be transferred, there is a case where the CD which should be uniform changes. In particular, the transfer device for a display device cannot be completely completed due to its large size (about 1000 mm to 3400 mm on one side), and the photoresist coating device or the development, the structure of the etching device, or the liquid flow of the wet process. Avoid situations where the processing conditions in the surface become uneven.

Further, the exposure apparatus used for exposing the photomask also has a situation in which the amount of light in the plane is generated due to the configuration of the apparatus.

The processing conditions and the exposure conditions described above are not uniform in the plane, and as long as the same device is used, it often occurs in a reproducible manner, but it is considered that by grasping this tendency, it is taken to reduce the All countermeasures to reduce the impact. Specifically, it is presumed that it is effective to reflect the CD unevenness of the transfer image which is caused by the in-plane unevenness of the processing conditions and the exposure conditions as described above to the design pattern data of the reticle. Corrections are made to offset the tendency of the CD due to such unevenness to increase or decrease with respect to the target value.

In the manufacture of the photomask, first, pattern data (design pattern data) is created based on the design of the component (display device, etc.) to be obtained. Next, the pattern data is used to draw on the mask substrate by the drawing device. The rendering device is rendered by illumination of an energy beam, in particular a laser rendering device using a laser beam.

The mask substrate may be, for example, a transparent mask, and a blank mask for forming an optical film (such as a light-shielding film) and a photoresist film to form a mask pattern. After the photoresist film of the photomask substrate is drawn, the photoresist pattern formed by the development is used as an etching mask, and the optical film is patterned to obtain a photomask having a transfer pattern.

However, when the photomask thus produced is exposed by an exposure device and the CD of the pattern formed on the transfer target is measured, there is a case where the CD changes due to the in-plane position on the transfer target. In other words, the CD of the pattern formed on the transfer target differs from the target CD of the design value (CD error), and the CD error amount may differ depending on the in-plane position on the transfer target. The main reason is as described above.

For the in-plane variation of such CD errors, it is conceivable to grasp the tendency of the error including the position and the error amount in advance, and to reflect the tendency of the control to the design pattern data of the mask to perform data correction to reduce the CD error. It can be recognized that the CD error amount can be suppressed to the entire allowable range throughout the entire area by using the appropriately corrected correction pattern data.

Further, it is described in Document 1 as follows. That is, the pattern is transferred onto the glass substrate coated with the photosensitive resin using a photomask manufactured at the initial design value, and the short-sized correction region of the color filter pattern obtained by each of the development and etching processes is drawn. . As a result, it was observed that the "pattern size on the lower end side of the mask was formed to be smaller than the design value as a whole". It is believed to be produced by processes such as etching. Therefore, based on the partitions drawn, the design values of the corresponding masks are adjusted. The design value of the photomask corresponding to the area to be corrected is adjusted to be larger than the initial setting value, and the size after the above process is set to an appropriate range.

Further, the problem proposed in Document 1 is that if the correction is uniformly performed based on the above-described drawing, the "step difference" of the large dimensional change appears at the boundary portion between the correction region and the adjacent region. Since the dimensional change in the vicinity of the boundary portion is expected to be as gentle as possible, in the method of Document 1, the correction amount of the boundary portion is randomly distributed rather than continuously arranging any correction value of the adjacent region. In this manner, the size of the color filter is not sharply changed around a certain region, and is formed into an average short-sized correction region.

However, according to the study by the inventors, the above method also has a problem. In other words, when the design value of the mask pattern is adjusted for the partition of the drawing, since the design pattern of the mask is different for each product to be obtained, even if the CD error is generated, there is a tendency to reproduce In the case of sex, the steps of adjusting the design value according to each design pattern are still needed. Specifically, if the CD error is caused by the exposure mechanism of the exposure device, it is helpful to perform the same correction by using the exposure device. However, when manufacturing a new mask having different design patterns, it is necessary to design one by one. The value is adjusted, so the efficiency is not good.

For example, the transfer pattern for manufacturing a display device includes a plurality of repeating patterns in which the unit patterns are regularly arranged. This design pattern data only retains the smallest unit of repetition (for example, 1 pixel) as a pattern, and can give its number of rows and rows in the X direction and the Y direction to represent millions and thousands. The pixel arrangement (hereinafter, also referred to as an array configuration). It has the advantage of being able to suppress the data capacity, and it also has the advantage of drastically reducing the man-hours required for the design.

However, when applying the array configuration, it is significantly more difficult to adjust the design value of the reticle only for a particular partition in the design pattern data.

Further, in Document 1, as described above, in order to make the dimensional change as gentle as possible in the vicinity of the boundary portion of the region to be corrected, a method of randomly arranging the correction values of the adjacent regions with the correction amount of the boundary portion is employed. In this case, there is a disadvantage that it is more difficult to apply the array configuration.

Therefore, the drawing method of the present invention is based on a specific design pattern data, and is formed on a photomask substrate, thereby forming a photomask including a transfer pattern for manufacturing an element for a display device, and is used in the photomask. a drawing device for drawing by an energy beam on the substrate, and the pattern drawing method includes the following steps: a beam intensity correction map forming step of generating a CD error with respect to a design value due to the manufacturing steps of the device for the display device And forming a beam intensity correction map for correcting the CD error based on the information of the CD error occurrence tendency including the position and the error amount of the CD error, and a drawing step of correcting the beam intensity Used in conjunction with the design pattern data described above, and depicted by the drawing device described above.

Here, the design pattern data is based on the design of the component to be obtained (here, the component for the display device), and the pattern material designed for a specific layer. Consider the case where the design pattern data is drawn to the reticle substrate by a scanning device (here, a laser drawing device) that scans the energy beam. Further, the laser drawing device is not particularly limited, and may be a laser beam scanning method on a mask substrate or a projection laser beam method using a mirror surface or the like.

The mask substrate refers to a blank mask formed on the transparent substrate to form an optical film for forming a mask pattern, and further a photoresist film is formed, or may be patterned on a specific optical film formed on the transparent substrate. Thereafter, in order to further pattern the other optical films on the same substrate, a photomask intermediate having a photoresist film is formed. The photoresist film can be either positive or negative, but the reticle in this field is generally positive.

As the optical film, in addition to the light shielding film, a semi-transmissive film having a specific light transmittance can be exemplified. The semi-transmissive film may be a phase shift film that shifts light of a representative wavelength (for example, any one of the i-line to the g-line range) by a wavelength of substantially 180 degrees in a wavelength included in the light for exposure, or may be A film having a phase shift amount of 90 degrees or less (preferably 60 degrees or less) is used. Approximately 180 degrees means 180 ± 30 degrees. The light transmittance of the semi-transmissive film can be, for example, about 5 to 60% with respect to the above representative wavelength.

Hereinafter, an embodiment of the present invention will be described by taking an example in which the CD accuracy of the pattern obtained on the transfer target is deteriorated by the exposure device used for the exposure mask. As a specific example, the case where the amount of irradiation light of the exposure light received by the reticle is uneven in the plane due to the structure of the exposure apparatus, and therefore, the transfer image formed on the transfer target body is exemplified. The CD at a particular location deviates from the target value of the design.

As the projection exposure apparatus for manufacturing a display device, as described above, there is a lens scanning method. This is performed by transferring a plurality of side-by-side projection lenses at the same time, scanning the entire pattern of the transfer pattern of the mask, and transferring the transfer pattern onto the object to be transferred. In order to prevent a gap from occurring between the plurality of lenses, the connecting portions of the adjacent lenses are provided with a slight overlapping illumination, and in the overlapping portion, the intensity of the irradiation is adjusted to be the same as the other regions (Fig. 1(a)).

However, no matter how finely adjusting the irradiation intensity of the above-mentioned connecting portion, a phenomenon in which the CD is slightly larger or slightly smaller than the other portions is observed on the position of the transfer portion corresponding to the connecting portion. Although such a CD change is very small, when it is a display device, since the CD of the trajectory of the connection portion is different from other regions, it may be recognized as a linear unevenness in human vision. As a cause of such a phenomenon, there may be a case where the light intensity in the above-mentioned connecting portion is slightly increased or decreased, and it may be due to a difference in conditions from other regions due to overlapping exposure. Fig. 1(b) illustrates a light intensity distribution when the light intensity of the connecting portion is larger than the other portions (upper side) and smaller than the other portions (lower side).

For example, when a negative photoresist (photosensitive resin) film is formed on a transfer target, when the light intensity is greater than other portions, in the developed photoresist pattern, the CD in the region is larger than the target value. When the light intensity is smaller than other parts, the CD is smaller than the target value. Therefore, if development is performed after exposure, and the film to be processed is etched using the formed photoresist pattern, linear unevenness is recognized due to the unevenness of the above-described light intensity. Figure 2 (a) shows this situation.

Therefore, in order to reduce such CD variation, it is considered that the CD of the portion of the transfer pattern of the photomask is adjusted in advance as in the method of Document 1. In other words, since the CD variation caused by the exposure apparatus is reproducible, it is considered to be useful to accurately grasp the tendency and form the design pattern data of the mask so as to cancel the CD variation. However, this method has problems as described above.

On the other hand, in the present invention, the correction for reducing the CD error is based on the information of the CD error occurrence tendency including the position of the CD error and the error amount, and the beam intensity for correcting the CD error is formed. Correct the map, not by adjusting the design pattern data. Next, in the step of drawing the mask, the beam intensity correction map is used together with the design pattern data.

In the present embodiment, a laser drawing device is used as the drawing device. The laser drawing device draws the irradiation intensity (power) of the laser beam emitted from the laser light source to a value set by the user. However, in a specific portion of the drawing area, the irradiation intensity of the laser beam is set to be higher or lower than other portions (the same portion as the design value), and this is saved as a beam intensity correction map in the memory device. . In other words, as long as the position and the amount of error of the CD error are obtained, the tendency of the CD error generated by the exposure device is grasped in advance, and the information of the CD error tendency is reflected, and the beam intensity of the drawing device is set on the coordinate basis to offset the CD error. The beam intensity correction map can be used.

At this time, the beam intensity correction map is independent of the design pattern of the specific mask. Therefore, when the display device is to be manufactured using the same exposure apparatus, the design of the transfer pattern provided in the photomask to be used may be used in common.

Since there is no need to implement changes to the design pattern data, there is no impact on all matters of forming the design pattern data by the array configuration.

As shown in Fig. 2(b), the beam intensity correction map for correcting the CD error may be corrected by correcting the beam intensity at the position where the CD error occurs by the exposure device (Fig. 2(a)).

Fig. 2(a) is a schematic view showing a position at which a CD error generated by an exposure device on a transfer target body occurs. Fig. 2(a) is a top plan view showing the distribution of light intensity (horizontal axis: position, vertical axis: light intensity (Intensity)) generated during exposure, and the lower side shows the observation due to the CD error. A schematic plan view of a situation in which linear unevenness occurs. The unevenness is generated corresponding to the connection portion of the plurality of lenses of the exposure device.

Fig. 2(b) is a schematic view of a reticle pattern drawn using a beam intensity correction map which corrects the beam intensity at the position where the CD error occurs by the exposure device to cancel CD error. Fig. 2(b) is a schematic diagram showing the correction amount of the beam intensity by CD change amount (horizontal axis: position, vertical axis: CD (unit: nm)), and the lower side is displayed by CD change. A top view of the beam intensity correction map.

Fig. 2(c) shows a transfer target obtained by pattern transfer by an exposure device using the photomask shown in Fig. 2(b). The linear unevenness due to the above CD error disappears. In Fig. 2(c), in order to facilitate understanding, the portion corresponding to the linear unevenness disappearing is indicated by a broken line.

A further advantage of correcting the CD error by beam intensity correction is that, unlike CD corrections that adjust the design pattern data, the correction of the beam intensity can be performed substantially substantially continuously (continuously). That is, the correction amount adjustment of the beam intensity can be set extremely finely based on the CD error described above. Therefore, the step of the light intensity can be made inconspicuous at the boundary between the corrected region and the uncorrected region or the region where the correction amount is different, and the smoothness is corrected to the extent that the boundary cannot be recognized. This situation is schematically shown in Figure 3. In Fig. 3, the horizontal axis shows the position, and the vertical axis shows the correction amount. As shown in FIG. 3(a), when the CD correction is performed by adjusting the design pattern data, a step of CD correction is generated. On the other hand, as shown in FIG. 3(b), when the beam intensity correction of the present invention is performed, substantially continuous CD correction can be realized.

Fig. 4 is a view showing an embodiment of the CD correction of the present invention.

Fig. 4 (a) is a CD distribution diagram (bubble map) showing a pattern (transferred image) formed on the transfer target when the transfer pattern for the mask is exposed using an exposure device. A CD error occurs in a specific region (linear in the vertical direction) due to a change in the intensity of the illumination generated at the lens connecting portion of the exposure device. Here, the CD formed in the pattern of the transfer target is displayed in accordance with the size relationship based on the target CD of the design value. Dark gray ● indicates that the CD is larger than the target CD, and white 〇 indicates that the CD is smaller than the target CD. The size of the bubble indicates the difference from the target CD.

In Fig. 4(a), a CD error which is linearly generated at a constant interval at a position corresponding to the position of the lens connecting portion of the exposure apparatus of the lens scanning method can be seen. According to Fig. 4(a), it is understood that the CD is larger than the target CD at a position corresponding to the lens connecting portion. Information on the tendency of the position or size of such a CD error can be obtained by exposure using a test mask or the like in which a specific transfer pattern is formed in advance.

Next, based on the information on the CD error occurrence tendency obtained as described above, a beam intensity correction map (beam intensity correction map forming step) is formed. The beam intensity correction map is a two-dimensional map formed by correcting the illumination intensity of the laser at each position on the coordinate to be greater than or less than the reference value to cancel the occurrence of the CD error. That is, it can also be referred to as a laser power distribution in a plane to be drawn on a coordinate basis.

Figure 4 (b) is a CD profile of the reticle of the present invention obtained using a beam intensity correction map based on the tendency of the position and error amount of the CD error according to Figure 4 (a). It is formed when the reticle is drawn to offset the CD error. That is, FIG. 4(b) shows a CD profile of the reticle obtained from the result of the drawing step, which is performed by using the design pattern data based on the desired design together with the beam intensity correction map described above. A depiction of the correction that reflects the intensity of the laser beam.

Fig. 4 (c) is a CD map of a pattern (transfer image) obtained on the transfer target when the same mask is used for exposure (exposure step) using the mask of Fig. 4 (b). The CD error of the lens connecting portion is substantially eliminated, and the variation in the in-plane CD is reduced.

In the present embodiment, the beam intensity correction map is independent of the design pattern data of the specific mask, and is a tendency to reflect the CD error generated on the transfer target, and the intensity correction is performed to offset the CD error. In the case where the exposure apparatus is in the case of the double exposure, when the exposure apparatus has the magnification, it may be formed in consideration of the magnification in the same manner as the transfer pattern for forming the mask.

According to the pattern drawing method of the present invention, for example, the CD on the photomask can be easily corrected by about 0.20 μm. When the correction range is insufficient to correspond to the amount of CD error generated, the adjustment can be made by changing the characteristics of the photoresist applied to the mask substrate or changing the laser irradiation reference amount at the time of drawing.

In order to further expand the correction range, multiple depictions can be used as appropriate. For example, if the drawing is repeated twice, it is useful to expand the range in which the beam intensity can be corrected. Correction of, for example, ±0.70 to ±1.5 μm can also be performed by appropriately using multiple drawing.

In the above-described embodiment, the CD error to be corrected is described as an example of the exposure apparatus using the projection exposure method using the lens scanning, but the present invention is not limited to the case where the lens connection portion of the exposure apparatus is generated as an example. The CD error. Further, the present invention is also applicable to the case of using a projection exposure apparatus of another mode.

As the projection exposure apparatus, the NA (numerical aperture) of the optical system is preferably 0.08 to 0.2, and the coherence factor σ is about 0.4 to 0.9. Further, as the light for exposure, a wavelength range of about 300 to 800 nm is used, and specifically, a light source including any of the i line, the h line, and the g line. It is also possible to use a lamp including all of the i line, the h line, and the g line.

Further, in the case of using an exposure apparatus of a proximity exposure method, the present invention is also applicable to a case where a CD unevenness is generated in the plane. In the proximity exposure, the photoreceptor is supported on the transfer target placed horizontally with a slight gap (Gap), and the transfer mask is provided with a transfer pattern. However, since the photomask is deflected by its own weight, and the support member of the photomask is subjected to a specific force, the size of the gap may be uneven in the plane, and therefore, the CD of the transferred image is also uneven. The present invention can also be suitably applied to the CD error caused by such an exposure mode.

In other words, the tendency of the error including the position of the CD error and the error amount is grasped in advance, and the beam intensity correction map is formed based on the tendency, and the ray mask can be drawn using the beam intensity correction map.

In the projection exposure, the wavelength range of the exposure light to be applied is the same as described above.

Of course, in the case other than the above, it is also possible to apply the present invention when a CD error having reproducibility is generated in the manufacturing step of the display device.

The transfer pattern to which the photomask of the present invention is applied is not particularly limited in design or use.

For example, it may be a person who includes a repeating pattern in which a plurality of unit patterns corresponding to pixels are regularly and repeatedly arranged. In this case, if a CD error occurs, the CD error is linearly arranged, or concentrated on a specific portion, etc., even if the amount of error is small, it is easily recognized by the human eye in the final display device. To. However, the correction of the CD error of the present invention is advantageous because it can be finely corrected to the extent that it is impossible to recognize the boundary between the portion where the correction is performed and the adjacent portion thereof.

The photoresist (photosensitive resin) on the transferred body may be positive or negative.

According to the present invention, it is also possible to respond to the trend of miniaturization of the pattern. That is, with the miniaturization of the pattern CD, the range of allowable CD variation becomes quite narrow, but the application of the present invention can be advantageously utilized.

CD‧‧‧ pattern width (critical dimension)

Int.‧‧‧Light intensity

Fig. 1(a) is a schematic view showing a lens configuration in a projection exposure apparatus for manufacturing a display device for a lens scanning method. Fig. 1(b) is a schematic view showing a light intensity distribution which is caused by overlapping irradiation of interconnected portions formed in a lens, so that the intensity of the irradiated light received by the transferred body is greater than the other portions (upper side), And less than the other parts (lower side). Fig. 2(a) is a schematic view showing a position at which a CD error occurs on a transfer target body according to an exposure apparatus (the upper graph shows the variation of the light intensity of the exposure device, and the lower image shows the resulting rotation. A top view of the state in which the CD error on the printed body is regarded as uneven. Fig. 2(b) is a schematic diagram of a beam intensity correction map for reducing the above-mentioned CD error (the upper graph is a schematic diagram showing the correction amount of the beam intensity by the CD variation amount, and the lower panel is the beam intensity correction map. A bird's-eye view of the change in CD). Fig. 2(c) is a plan view showing a state in which the linear unevenness due to the CD error disappears when the mask is exposed by the correction. Fig. 3(a) is a conceptual diagram of the step of CD correction generated when CD correction is performed by adjusting design pattern data, and Fig. 3(b) shows substantially continuous CD correction obtained when performing beam intensity correction of the present invention. Conceptual illustration. Fig. 4 (a) is a view showing a CD distribution pattern formed on a transfer target body due to a variation in irradiation intensity generated at a lens connecting portion of the exposure device. Figure 4 (b) is a CD distribution diagram showing a photomask formed by the drawing method of the present invention. Fig. 4 (c) is a CD distribution diagram showing a transfer image obtained by exposing the photomask having the CD distribution of Fig. 4 (b) to the transfer target.

Claims (9)

A pattern drawing method for drawing on a photomask substrate based on specific design pattern data, thereby forming a photomask including a transfer pattern for manufacturing an element for a display device, wherein: a drawing device for drawing by an energy beam on a photomask substrate, and the pattern drawing method includes the following steps: a beam intensity correction map forming step is generated with respect to a design value due to a manufacturing step of the device for the display device In the case of the CD error, a beam intensity correction map for correcting the CD error is formed based on the information of the CD error occurrence tendency including the position and the error amount of the CD error, and a drawing step of the beam intensity The correction map is used with the design pattern data described above and is depicted by the drawing device described above. The pattern drawing method of claim 1, wherein the manufacturing step of the display device component comprises an exposure step of exposing the photomask by an exposure device, and the CD error is an error due to exposure conditions of the exposure device. The pattern drawing method of claim 2, wherein the exposure device is a projection exposure method that transfers a transfer pattern of the photomask to the transfer target by scanning a plurality of lenses. The pattern drawing method of claim 2, wherein the exposure means is applied to a proximity exposure mode. The pattern drawing method according to any one of claims 1 to 4, wherein the transfer pattern includes a repeating pattern in which a plurality of unit patterns are regularly arranged. A pattern drawing method according to any one of claims 1 to 4, wherein in the above-described drawing step, multiple drawing is performed. A method of manufacturing a reticle comprising the drawing step of any one of claims 1 to 6. A manufacturing method of an element for a display device, comprising: a step of preparing a photomask prepared according to the manufacturing method of claim 7, and transferring the transfer pattern to a transfer by an exposure device applying a projection exposure method In the above, the projection exposure method transfers the transfer pattern of the photomask to the transfer target by scanning a plurality of lenses. A manufacturing method of an element for a display device, comprising: a step of preparing a photomask formed according to the manufacturing method of claim 7, and transferring the transfer pattern to the image by applying an exposure device of a proximity exposure method On the transfer body.