TW201520683A - Photomask, method of manufacturing a photomask, pattern transfer method and method of manufacturing a display device - Google Patents

Abstract

A photomask according to this invention has a transfer pattern adapted to form a device pattern of a line width Wp on an object. The transfer pattern includes a first void pattern having a line width Wm. The relationship between the line width Wp of the device pattern and the line width Wm of the first void pattern satisfies the following formulas (1) and (2). Wp < 10[mu]m... (1) 1 ≤ (Wm-Wp)/2 ≤ 4 ([mu]m)... (2).

Description

Photomask, photomask manufacturing method, pattern transfer method, and display device manufacturing method

The present invention relates to a photomask including a transfer pattern, a method of manufacturing the photomask, a pattern transfer method using the photomask, and a method of manufacturing the display device.

In recent years, in the manufacture of display devices such as liquid crystal display devices (LCDs), it has been desired to increase the production efficiency by increasing the size of the photomasks used, and to pursue high transfer precision. The liquid crystal display device has a structure in which a TFT substrate on which a TFT (Thin Film Transistor) array is formed, a color filter in which an RGB pattern is formed, and a liquid crystal sealed therebetween are provided.

1A to 1C are schematic views showing an example of a color filter. As shown in FIGS. 1A to 1C, the color filter includes a coloring portion 101 that selectively transmits light of only a specific wavelength, and a black matrix 102 (light shielding portion) that shields light. The colored portion 101 is colored in red, green, and blue (RGB) colors. Fig. 1A is a color filter showing a stripe arrangement, and Fig. 1B is a color filter showing a mosaic arrangement. 1C is a cross-sectional schematic view showing a line A-A of FIG. 1A or a line B-B of FIG. 1B.

When a black array layer or a colored layer is formed on a light-transmitting substrate using a photomask, it is most advantageous to apply proximity (proximity) exposure. The reason for this is that the proximity exposure does not require a complicated optical system as compared to projection (projection) exposure. The cost of the device is also low, so the production efficiency is high.

Fig. 2 is a schematic view showing an exposure apparatus for performing proximity exposure. As shown in FIG. 2, the exposure apparatus 110 that performs the proximity exposure includes a light source 111, an elliptical mirror 112 functioning as a condensing mirror, an integrator 113, and a collimation lens 114. As the light source 111, a mercury lamp or the like having a wavelength region including an i line, an h line, and a g line is generally used.

In the exposure device 110, the light beam emitted from the light source 111 is a beam of uniform illumination by the elliptical mirror 112, the integrator 113, and the collimator lens 114. Moreover, the light beam is irradiated to the reticle 120. The light-transmitting material passing through the reticle 120 exposes the photosensitive material film on the layer to be processed of the transfer-receiving body 121 disposed from the reticle 120 by a specific proximity gap pg.

In the proximity exposure, the transfer target 121 on which the photosensitive material film is formed is horizontally placed on a stage (not shown), and the mask 120 is formed on the pattern surface 120a on which the transfer pattern is formed. The transfer body 121 is held in a facing manner. Then, the pattern is transferred to the photosensitive material film of the transfer target 121 by irradiating light from the back side of the mask 120. At this time, a specific interval (close to the gap) is provided between the photomask 120 and the transfer target body 121.

In general, when the photomask is attached to the exposure apparatus for proximity exposure, the holding member of the exposure apparatus holds an area (also referred to as a pattern) on the main surface on which the transfer pattern is formed and on which the transfer pattern is formed. Outside the area). That is, the reticle is held by the holding member of the exposure device abutting on the opposite side or the four sides of the outer periphery of the reticle forming the square shape. Further, the photomask is held in a substantially horizontal position and placed in the exposure apparatus in a substantially horizontal posture.

Further, when the proximity exposure is applied, it is difficult to perform the correction of the deformation by the optical means at the time of transfer, and the transfer accuracy is likely to deteriorate as compared with the projection exposure.

For example, since the photomask is bent by its own weight, the curvature of the mask is corrected to some extent by the holding mechanism of the exposure apparatus. For example, in Patent Document 1, There is a method of correcting the bending by applying a specific pressure from above the reticle to the outside of the support point of the holding member for supporting the reticle in the support mechanism for horizontally supporting the flat reticle.

Further, Patent Document 2 describes a photomask substrate for reducing variations in position due to proximity of a gap when mounted in a proximity exposure apparatus.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-306832

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2012-256798

However, even if it is useful to reduce the influence on the pattern transfer caused by the curvature of the mask, the inventors have found that the manufacture of the precision display device for the above-mentioned use is still insufficient.

For example, it can be seen that the main surface of the photomask substrate is deformed by the manner in which the photomask is held or the holding member for reducing the curvature, and the direction or magnitude of the force applied to the photomask is different. Further, it is almost impossible to completely suppress the in-plane variation close to the gap due to the flatness of the stage of the exposure apparatus or the thickness distribution of the transfer target placed on the stage of the exposure apparatus. Patent Document 2 describes a method of reducing the in-plane variation of such a close gap by the shape of the mask substrate. However, the in-plane variation close to the gap is complicated by the exposure device used.

In the proximity exposure, if unevenness in the surface close to the gap occurs, it is more difficult to transfer the removal pattern of the fine line width. The reason for this is that, in the edge of the slit-like removal pattern, diffraction of light is generated, and the removal pattern becomes a finer width, and the influence of the diffraction and interference is increased to such an extent that it cannot be ignored.

Figure 3 is a diagram showing light intensity distribution of interference formed by transmitted light of a near exposure Figure. In FIG. 3, the photomask 120 provided with the removal pattern is provided so that the pattern surface 120a opposes the to-be-transferred body 121. At this time, a close gap pg is provided between the photomask 120 and the transfer target body 121.

The curve 122 schematically represents a light intensity curve of the interference pattern formed by the transmitted light when the light is irradiated from the back side of the mask 120. As shown in FIG. 3, light is diffracted at the edge of the removed pattern of the pattern surface 120a to form a complex interference pattern.

In the proximity exposure, gaps of different sizes are generated due to the position in the plane, and different diffraction patterns corresponding thereto are generated, and the line width of the formed pattern or the tendency of the light irradiation amount is uneven. However, the intensity distribution of the transmitted light actually received by the transfer body at each position in the plane cannot be easily estimated.

However, the color filter or the TFT substrate shown in Fig. 1 is manufactured by using a plurality of photomasks by applying a photolithography step. In recent years, as the final product, that is, the brightness of the display device, the operating speed, and the like have been increased in height, the pattern of the photomask has been fined, and the line width accuracy as a result of the transfer has become stricter.

For example, it is considered that in the black matrix for LCD, the high performance sought by the current LCD, that is, (1) speed of operation, (2) brightness, (3) reduction of power consumption, and (4) high definition, thinning at least (2) to (4) are valid. Specifically, by thinning the black matrix, the amount of transmitted light is increased, so that the brightness of the LCD can be obtained. Moreover, if the brightness is greatly increased, the power consumption of the backlight of the LCD can be reduced. Furthermore, the sharpness of the image can be improved by thinning the black matrix.

In order to form a black matrix by a black negative photosensitive material, in a large-area light-shielding region, it is necessary to use a matrix-shaped removal pattern (grid-like) provided with an aggregate formed with linear removal patterns in the X direction and the Y direction. A mask for removing the pattern of the transfer pattern. However, it is not easy to delicately form a fine width removal pattern.

In the case of forming a residual pattern composed of a linear film pattern in a large-area light-transmitting region, in order to obtain a desired line width, wet etching is used. The side etching allows for fine adjustment of the line width. However, in the removal pattern, conditions such as drawing, development, etching, and the like must be determined in advance. Further, even if the line width is slightly changed, if the line width itself is fine, there is a problem that the variation causes a large change in the light transmission behavior.

Further, even when a photomask that performs line width control is used, there is a further problem in transferring the transfer pattern onto the transfer target.

When exposure is performed using a transfer pattern having a removal pattern sandwiched by the light shielding portion, the light intensity distribution on the transfer target is subjected to light diffraction as described above as the line width of the removal pattern is made fine. The impact.

4A and 4B are views schematically showing the relationship between the line width of the removed pattern and the light intensity distribution on the object to be transferred. In FIGS. 4A and 4B, the transfer pattern is composed of a light shielding portion 103 and a removal pattern 104 sandwiched by the light shielding portion 103.

Fig. 4A shows the light intensity distribution between C-D when the line width of the removal pattern 104 is a1. Fig. 4B shows the light intensity distribution between E-F when the line width of the removal pattern 104 is a2 (a2 < a1). Thus, when the line width of the removal pattern 104 is a2 < a1, the peak of the light intensity distribution of the line width a2 shown in FIG. 4B is compared with the line width shown in FIG. 4A. The peak of the light intensity distribution of a1 is lowered. That is, the smaller the line width of the removal pattern 104 is, the lower the peak of the light intensity distribution is, and the problem that it is difficult to sufficiently sensitize the photosensitive material on the transfer target is generated.

The present invention has been made in view of the above, and an object of the present invention is to provide a photomask and a photomask manufacturing method capable of finely controlling the line width or the amount of light when the removal pattern of the fine line width is transferred onto the object to be transferred. , a pattern transfer method, and a method of manufacturing a display device.

The reticle of the present invention is characterized in that it includes a transfer pattern for forming a device pattern of a line width Wp on a transfer target, and has a main surface having a side of 300 mm or more, and the above-mentioned rotation The printed pattern has a light-shielding area which is attached to the transparent base. Forming at least a light shielding film on the plate; and a first removal pattern disposed adjacent to the light shielding region, and corresponding to the device pattern, a line width of Wm, and a line width Wp of the device pattern and the first removal pattern The relationship between the line width Wm and the following formula (1) and formula (2): Wp < 10 μm (1)

1≦(Wm-Wp)/2≦4(μm)...(2).

According to the reticle, the line width Wm of the first removal pattern in the transfer pattern for the reticle necessary for forming the device pattern of the line width Wp on the transfer target satisfies a specific amount of bias ( Since (Wm-Wp)/2 (μm)) is adjusted, the amount of light reaching the transfer target can be adjusted, and CD unevenness of the device pattern due to unevenness in the close gap can be suppressed. Therefore, when the removal pattern of the fine line width is transferred onto the object to be transferred, the control of the line width or the amount of light can be performed exquisitely.

In the above-described reticle, the first removal pattern may be configured by a light-transmitting portion in which the surface of the transparent substrate is exposed.

Further, in the photomask, the first removal pattern may be configured by forming a semi-transmissive portion of the semi-transmissive film on the transparent substrate.

Further, in the photomask, the light transmittance of the semi-transmissive film may be 20 to 60%.

Further, in the above-described reticle, the transfer pattern may include a plurality of the first removal patterns having a line shape having a line width Wm, and have a width between the first removal patterns adjacent in the width direction. (3 × Wm) or more of the above-mentioned portion of the light-shielding region.

Further, in the photomask, the transfer pattern may further include a second removal pattern having a line width Wn (Wn > Wm), and the second removal pattern may be formed by a light transmission portion.

Further, in the reticle, the reticle may be a reticle used for proximity exposure in a range of 10 to 200 μm in close proximity to the reticle.

The manufacturing method of the reticle of the present invention is characterized in that the reticle is provided for being rotated Forming a transfer pattern of the device pattern of the line width Wp on the printed body, and the method of manufacturing the photomask includes the steps of: forming a blank mask on the transparent substrate on which the optical film including at least the light shielding film is formed, After the film is subjected to the photolithography step, the transfer pattern is formed by patterning including wet etching, and the transfer pattern has a light-shielding region on which at least the light-shielding region is formed. And a first removal pattern disposed adjacent to the light shielding region, and corresponding to the device pattern, a line width of Wm; and a line width Wp of the device pattern and a line width Wm of the first removal pattern The relationship satisfies the following equations (1) and (2): Wp < 10 μm (1)

1≦(Wm-Wp)/2≦4(μm)...(2).

The pattern transfer method of the present invention is characterized in that it is used to form a device pattern having a line width Wp on a transfer target by a close exposure using a photomask having a transfer pattern, and using the above In the photomask manufactured by the above-described photomask manufacturing method, the negative photosensitive material film formed on the to-be-transferred body is exposed by a proximity exposure apparatus.

The method of manufacturing a display device of the present invention is characterized in that the above-described pattern transfer method is used.

According to the present invention, when the removal pattern of the fine line width is transferred onto the object to be transferred, the control of the line width or the amount of light can be performed remarkably.

10‧‧‧Photomask

10a‧‧‧Transparent substrate

10b‧‧‧ shading area

10c‧‧‧1st removal pattern

11a‧‧‧Transferred body

11b‧‧‧1st device pattern

11c‧‧‧2nd device pattern

12‧‧‧Elliptical mirror

12a‧‧‧Transparent substrate

12b‧‧‧ shading area

12c‧‧‧1st removal pattern

14‧‧‧ Collimating lens

14a‧‧‧Transparent substrate

14b‧‧‧ shading area

14c‧‧‧1st removal pattern

14d‧‧‧2nd removal pattern

20‧‧‧Black matrix

20a‧‧‧ pixel pattern

20b‧‧‧ surrounding area

21a‧‧‧Lighting Department

21b ₁ ‧‧‧1st removal pattern

21b ₂ ‧‧‧2nd removal pattern

21c‧‧‧1st removal pattern

22‧‧‧ device pattern

23a‧‧‧Lighting Department

23b‧‧‧1st removal pattern

23c‧‧‧1st removal pattern

24‧‧‧ device pattern

24a‧‧‧Lighting Department

24b‧‧‧1st removal pattern

25a‧‧‧ device pattern

25b‧‧‧ device pattern

26a‧‧‧Lighting Department

26b‧‧‧1st removal pattern

26c‧‧‧2nd removal pattern

27a‧‧‧ device pattern

27b‧‧‧ device pattern

28a‧‧‧Lighting Department

28b‧‧‧1st removal pattern

28c‧‧‧2nd removal pattern

30‧‧‧ Blank mask

30a‧‧‧ Blank mask

31‧‧‧Transparent substrate

32‧‧‧Shade film

32a‧‧‧Shade film pattern

33‧‧‧ photoresist film

33a‧‧‧ photoresist pattern

34‧‧‧ Semi-transparent film

34a‧‧‧Semi-transparent film pattern

35‧‧‧ photoresist film

35a‧‧‧ photoresist pattern

40‧‧‧ Blank mask

40a‧‧‧ Blank mask

41‧‧‧Transparent substrate

42‧‧‧ Semi-transparent film

42a‧‧‧ Semi-transparent film pattern

43‧‧‧Shade film

43a‧‧‧Shade film pattern

44‧‧‧ photoresist film

44a‧‧‧ photoresist film

45‧‧‧ photoresist film

45a‧‧‧ photoresist pattern

50‧‧‧Photomask

50a‧‧‧Lighting Department

50b‧‧‧Removal pattern

51‧‧‧Photomask

51a‧‧‧Lighting Department

51b‧‧‧Removal pattern

101‧‧‧Coloring section

102‧‧‧Black array (shading part)

103‧‧‧Lighting Department

104‧‧‧Removal pattern

110‧‧‧Exposure device

111‧‧‧Prepared light source

112‧‧‧Elliptical mirror

113‧‧‧ integrator

114‧‧‧ Collimating lens

120‧‧‧Photomask

120a‧‧‧pattern surface

121‧‧‧Transferable body

122‧‧‧ Curve

170a‧‧‧ Curve

170b‧‧‧ Curve

170c‧‧‧ Curve

180a‧‧‧ Curve

180b‧‧‧ Curve

180c‧‧‧ curve

190a‧‧‧ Curve

190b‧‧‧ Curve

200a‧‧‧ Curve

200b‧‧‧ Curve

200c‧‧‧ Curve

210a‧‧‧ Curve

210b‧‧‧ Curve

210c‧‧‧ Curve

220a‧‧‧ Curve

220b‧‧‧ Curve

220c‧‧‧ Curve

A1‧‧‧ line width

A2‧‧‧ line width

Pg‧‧ ‧ close to the gap

Wm‧‧‧ line width

Wn‧‧‧ line width

Wp‧‧‧ line width

Wq‧‧‧ line width

X-Y‧‧ Direction

Fig. 1A is a schematic view showing an example of a color filter arranged in stripes.

Fig. 1B is a schematic view showing an example of a color filter of a mosaic arrangement.

1C is a cross-sectional schematic view taken along line A-A of FIG. 1A or line B-B of FIG. 1B.

Fig. 2 is a schematic view showing an exposure apparatus for performing proximity exposure.

Figure 3 is a diagram showing light intensity distribution under interference of formation of transmitted light in proximity exposure Figure.

4A is a view showing a relationship between a line width (a1) of a removal pattern constituting a transfer pattern and a light intensity distribution on a transfer target.

4B is a view showing the relationship between the line width (a2) of the removal pattern constituting the transfer pattern and the light intensity distribution on the transfer target.

Fig. 5 is a schematic view showing an example of a photomask according to an embodiment of the present invention and a transfer member for transferring a first device pattern using the photomask.

Fig. 6 is a schematic view showing an example of a photomask according to an embodiment of the present invention and a transfer member for transferring a first device pattern using the photomask.

Fig. 7 is a schematic view showing an example of a photomask according to an embodiment of the present invention and a transfer member for transferring a first device pattern and a second device pattern using the mask.

Fig. 8 is a view showing an example of a black matrix manufactured by using the photomask of the above embodiment.

Fig. 9A is a view showing a part of a pixel portion of a matrix-shaped photomask.

Fig. 9B is a view showing a part of a pixel portion of a matrix-shaped photomask.

Fig. 10A is a view showing an example of black stripes in order to explain the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 10B is a view showing an example of a reticle for explaining the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 10C is a view showing an example of a reticle for explaining the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 11A is a view showing an example of a black matrix for explaining the relationship between the device pattern formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 11B is a view showing an example of a reticle for explaining the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 12A is a view showing an example of a black matrix for explaining the relationship between the device pattern formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 12B is a view showing an example of a reticle for explaining the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 13A is a view showing an example of a black matrix for explaining the relationship between the device pattern formed on the transfer target and the shape of the removal pattern in the reticle.

Fig. 13B is a view showing an example of a photomask in order to explain the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the mask.

14(a) through 14(i) are cross-sectional views for explaining the method of manufacturing the first photomask of the above embodiment.

15(a) to (i) are cross-sectional views for explaining the method of manufacturing the second photomask of the above embodiment.

Fig. 16A is a view showing a mode of a photomask (binary mask) used in optical simulation of an embodiment of the present invention.

Fig. 16B is a view showing a model of a mask (halftone mask) used for optical simulation of an embodiment of the present invention.

Fig. 17A is a view showing a simulation result of a comparative example.

Fig. 17B is a view showing a simulation result of a comparative example.

Fig. 17C is a view showing a simulation result of a comparative example.

Fig. 18A is a view showing a simulation result of the embodiment 1 of the present invention.

Fig. 18B is a view showing a simulation result of the embodiment 1 of the present invention.

Fig. 19 is a view showing the result of simulation of Example 2 of the present invention.

Fig. 20A is a view showing a simulation result of Example 3 of the present invention.

Fig. 20B is a view showing the result of simulation of Example 3 of the present invention.

Fig. 20C is a view showing the result of simulation of Example 3 of the present invention.

Fig. 21A is a view showing the result of simulation of Example 4 of the present invention.

Fig. 21B is a view showing the result of simulation of Example 4 of the present invention.

Fig. 21C is a view showing the result of simulation of Example 4 of the present invention.

Fig. 22A is a view showing a simulation result of Example 5 of the present invention.

Fig. 22B is a view showing the result of simulation of Example 5 of the present invention.

Fig. 22C is a view showing the result of simulation of Example 5 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 5 and Fig. 6 are schematic views showing an example of a photomask according to the embodiment and a transfer member for transferring a first device pattern using the mask.

The photomask 10 shown in FIG. 5 has a light-shielding region 10b which is formed by providing a light-shielding film on the transparent substrate 10a, and a first removal pattern 10c having a line width Wm. The light-shielding region 10b and the first removal pattern 10c constitute a transfer pattern (for example, a pixel pattern). Further, the first removal pattern 10c is configured by a light-transmitting portion in which the surface of the transparent substrate 10a is exposed.

On the other hand, the photomask 12 shown in FIG. 6 has a light-shielding region 12b which is formed by providing a light-shielding film or a light-shielding film and a semi-transmissive film on the transparent substrate 12a, and a first removal pattern 12c of the line width Wm. It is configured by providing only a semi-transmissive film on the transparent substrate 12a. The light shielding region 12b and the first removal pattern 12c constitute a transfer pattern (for example, a pixel pattern).

Further, in the photomask 12 shown in FIG. 6, a semi-transmissive film may be formed on the transparent substrate 12a, and a light-shielding film may be laminated on the semi-transmissive film to constitute a light-shielding region, or may be transparent. Only a light shielding film is formed on the substrate to constitute a light shielding region.

The line width Critical Dimension (CD, critical dimension) means a line width if it is a line pattern, and a hole pattern (or a short diameter) if it is a hole pattern.

The photomask 10 (12) has a main surface having a side of 300 mm or more. The one side is equivalent to one side when it is square outside the mask 10 (12), and corresponds to its short side in the case of a rectangle. In the mask of the present embodiment, even if it is bent or caused by strain caused by the holding jig for bending, the in-plane unevenness of the close gap is caused, and the effect of deteriorating the transfer property is suppressed. A remarkable effect can be obtained in a large reticle of 300 mm or more. Furthermore, the square shape of 600 mm or more (6th generation) on one side In the mask, a greater effect can be obtained.

The first removal pattern 10c (12c) is disposed surrounded by the light-shielding region 10b (12b). In other words, the first removal pattern 10c (12c) is disposed at least in a state in which the light shielding regions 10b (12b) are sandwiched from both sides. For example, when the first removal pattern 10c (12c) has a line shape having a specific width, a light shielding region is disposed adjacent to both sides of the line. Moreover, when the first removal pattern 10c (12c) is a hole pattern, the light shielding region is disposed so as to surround the hole pattern.

The first device pattern 11b formed on the transfer target 11a such as a color filter substrate has a fine width (Wp<10 μm). The first device pattern 11b can be used as, for example, a photo spacer (PS) used as a black matrix (BM) or a black stripe (BS) for a color filter. Specifically, the line width Wp of the first device pattern 11b preferably satisfies 2 μm ≦ Wp < 10 μm. When the first device pattern 11b is used as a black matrix or a black stripe, the line width Wp preferably satisfies 3 μm ≦ Wp < 8 μm, and more preferably satisfies 4 μm ≦ Wp < 7 μm.

On the other hand, the line width Wm of the first removal pattern 10c (12c) constituting the transfer pattern preferably satisfies 1 ≦(Wm - Wp) / 2 ≦ 4 (μm). Here, the line width Wm of the first removal pattern 10c (12c) is a width which is offset from the line width Wp of the first device pattern 11b on both sides. That is, when the deviation is β, 1≦β≦4 (μm) is established. In this manner, the first device pattern 11b having a width of only one side β is added to the line width Wm of the first removal pattern 10c on the mask 10, and the transfer is performed on the transfer target 11a. Further, the line width Wm of the first removal pattern 10c (12c) is more preferably 1.2 Wp ≦ Wm ≦ 3.0 Wp. Further, the line width Wm of the first removal pattern 10c (12c) more preferably satisfies 1.4 Wp ≦ Wm ≦ 3.0 Wp.

When the first removal pattern 10c is formed of a light-transmitting portion exposed on the surface of the transparent substrate 10a, the line width Wm of the first removal pattern 10c preferably satisfies 1.4 Wp ≦ Wm ≦ 2.0 Wp.

On the other hand, when the first removal pattern 12c is formed by the semi-transmissive portion in which the semi-transmissive film is formed on the transparent substrate 12a, the line width of the first removal pattern 12c is higher than that of the mask 12. Good to meet 1.2Wp≦Wm≦2.6Wp. Further, the line width Wm of the first removal pattern 12c is more preferably 1.0 μm ≦ (Wm - Wp) / 2 ≦ 3.0 μm, that is, 1.0 μm ≦ β ≦ 3.0 μm.

In the photomask 12, it is preferable that the semi-transmissive film is formed not only in the portion corresponding to the first removal pattern 12c but also in the light-shielding region portion. That is, in the light-shielding region, it is preferable to form a laminated light-shielding film and a semi-transmissive film. The reason for this is that in the case where the patterned light-shielding film and the patterned semi-transmissive film are respectively formed on the transparent substrate 12a, it is necessary to have an etching step of each film, and it is not easy to sufficiently obtain the alignment precision.

However, for example, in a region where a fine pattern such as a pixel pattern is not present (for example, a peripheral region of the reticle, refer to FIG. 8), a light-transmitting portion where the surface of the transparent substrate is exposed may be used, and in this case, film formation may be removed. Semi-transparent film. Alternatively, the film formation of the semi-transmissive film is not performed in such a region, and the transparent substrate 12a is exposed. The reason for this is that the alignment accuracy of patterning of such regions may not be as high as within the pixel pattern.

In the photomask 12, the light transmittance T of the semi-transmissive film is preferably 20 to 60%. Further, the light transmittance T of the semi-transmissive film is preferably from 30 to 55%, more preferably from 30 to 50%. The reason for this is that if the light transmittance T of the semi-transmissive film is excessively increased, the film thickness of the semi-transmissive film is decreased. In this case, a slight film thickness variation of the semi-transmissive film causes the transmittance to be caused. The tendency to change relatively large. On the other hand, the reason is that if the transmittance of the semi-transmissive film is too small, there is a risk that the amount of light transmitted through the fine first removal pattern 12c is insufficient.

The light transmittance T of the exposure of the semi-transmissive film is a transmittance of the semi-transmissive portion in which the semi-transmissive film is formed on the transparent substrate 12a when the light transmittance of the exposure of the transparent substrate 12a is 100%. However, it is assumed that the semi-transmissive portion has a width sufficient to achieve a degree that is not affected by the adjacent pattern.

The light transmittance T of the exposure is preferably a transmittance of all wavelengths in the i-line, the h-line, and the g-line for the representative wavelength in the wavelength region including the i-th to g-line used as the light to be exposed.

The transfer pattern provided in the photomask may further have a second removal pattern having a line width Wn (Wn > Wm). FIG. 7 is a schematic view showing an example of a photomask having a second removal pattern and a transfer member that transfers the second removal pattern using the photomask.

The photomask 14 shown in FIG. 7 has a light-shielding film or a light-shielding region 14b in which a light-shielding film and a semi-transmissive film are laminated, a first removal pattern 14c having a line width Wm, and a line width Wn on a transparent substrate 14a such as quartz. The second removal pattern 14d. The light-shielding region 14b, the first removal pattern 14c, and the second removal pattern 14d constitute a transfer pattern (for example, a pixel pattern). Further, the first removal pattern 14c is configured by a semi-transmissive portion in which a semi-transmissive film is formed on the transparent substrate 14a. The second removal pattern 14d is configured by a light-transmitting portion in which the surface of the transparent substrate 14a is exposed.

The second removal pattern 14d in the photomask 14 is used to form the second device pattern 11c having the line width Wq on the transfer target 11a. The line width Wn of the second removal pattern 14d is 8 μm ≦ Wn, and more preferably 10 μm ≦ Wn. In other words, the second removal pattern 14d has a larger line width than the first removal pattern 14c, and can also be made to pass through the light transmission portion as compared with the use of the submersible portion by the following semi-transmissive portion. The amount of transmitted light obtained by the composition is prioritized.

The transfer pattern in the photomask 10 (12, 14) preferably has a plurality of first removal patterns 10c (12c, 14c) each having a line width Wm, and is first removed in the width direction. Between the patterns 10c (12c, 14c), there is a portion in which the light-shielding region having a width (3 × Wm) or more is interposed.

As a result of the interference between the diffracted light generated at the edge of the slit, which is the pattern of the removal, and the light generated thereby, the light intensity distribution described below is formed on the object to be transferred 11a. The light intensity distribution is preferably as follows (see FIGS. 17A, B, C to 22A, B, and C), and is a light intensity curve having a single peak at the center. The light intensity distribution is preferably a bell-shaped peak such as a Gaussian distribution having a single peak in the center and monotonously increasing or monotonically decreasing on both sides of the peak. This is obtained by appropriately selecting the design of the transfer pattern (removing the pattern line width, the transmittance), and the exposure conditions (illuminance, collimation angle).

It means that it is generated on both edges of the first removal pattern 10c (12c, 14c). The diffracted light under the diffraction of light causes complex interference according to the width of the first removal pattern 10c (12c, 14c), and as a result, the distribution of the synthesized light intensity forms a single peak. The light intensity distribution formed on the transfer target 11a is preferably such that a single peak is formed in a region of ± Wp/2 with respect to the center of the width direction. Further, there may be a side peak on the outer side of the above region.

When the interval between the adjacent first removal patterns 10c (12c, 14c) is small, if the adjacent first removal patterns 10c (12c, 14c) interfere with each other by transmitted light, they are formed on the transferred body. The shape of the light intensity distribution of 11a changes and is further complicated. As a result, the light intensity distribution does not necessarily represent a single peak, and it is difficult to form a photosensitive material film pattern having a good resolution on the transferred body 11a.

The transfer pattern of the photomask 10 (12, 14) can be used for the manufacture of a black matrix or a black stripe.

Fig. 8 is a view showing an example of a black matrix manufactured using the photomask 10 (12) of the present embodiment. Fig. 8 is a view showing a black matrix pattern panorama of a panel amount. The black matrix 20 shown in FIG. 8 is composed of a pixel pattern 20a and a peripheral region 20b. The pattern width of the peripheral region 20b is larger than the pattern width of the pixel pattern region, but the size ratio of the other patterns, or the area and arrangement position of the pixel pattern are appropriately changed depending on the device to be obtained.

9A and 9B are views showing a part of a pixel portion of a photomask. Fig. 9A shows a matrix mask for forming a pixel pattern region 20a of the black matrix 20 shown in Fig. 8. Here, the light-shielding regions of the quadrangular shape are arranged in a row (matrix) with a space therebetween, and a removal pattern is formed between the adjacent light-shielding regions. However, the light-shielding region does not have to be a quadrangular shape, and a light-shielding region of a fixed shape different from this may be regularly arranged. The mask shown in FIG. 9A has a linear removal of the first removal pattern 21b ₁ in which the light shielding portion 21a and the line width Wm are linear, and the line width Wn (Wn > Wm) intersecting the first removal pattern 21b ₁ . Pattern 21b ₂ .

On the other hand, Fig. 9B shows a strip-shaped photomask for forming black stripes. Figure 9B The photomask shown has a light-shielding portion 21a and a first removal pattern 21c having a line width Wm.

10A, 10B, 10C to 13A, and 13B are views for explaining the relationship between the pattern of the device formed on the transfer target and the shape of the removal pattern in the reticle. In addition, in these figures, the peripheral area of a photomask is abbreviate|omitted, and only the pixel pattern area is shown.

Fig. 10A shows a black stripe formed by a linear device pattern 22 extending in the Y direction. In order to form the device pattern as shown in FIG. 10A, the photomask has a first removal pattern of a line width Wm extending in the Y direction. The mask shown in FIG. 10B has a light shielding portion 23a and a first removal pattern 23b formed of a light transmission portion. The photomask shown in FIG. 10C has a light shielding portion 23a and a first removal pattern 23c composed of a semi-transmissive portion.

Fig. 11A shows a black matrix formed of linear device patterns 24 extending in the X direction and the Y direction orthogonal to each other. In order to form the device pattern as shown in FIG. 11A, the photomask shown in FIG. 11B has a first removal pattern 24b having a line width Wm extending in the X direction and the Y direction, respectively. The photomask shown in FIG. 11B has a light shielding portion 24a and a first removal pattern 24b having a lattice shape formed by a semi-transmissive portion.

Fig. 12A shows a black matrix composed of a linear device pattern 25a extending in the Y direction and a linear device pattern 25b having a line width Wq (Wq > Wp) extending in the X direction. In order to form the device pattern as shown in FIG. 12A, the photomask shown in FIG. 12B has a linear first line 1b of the line width Wm extending in the Y direction and a line width Wn extending in the X direction (Wn>Wm). The linear second removal pattern 26c. The photomask shown in FIG. 12B has a light shielding portion 26a and a first removal pattern 26b and a second removal pattern 26c which are formed by a semi-transmissive portion.

The line width Wn of the second removal pattern 26c is 8 μm ≦ Wn, and more preferably 10 μm ≦ Wn. The upper limit of the line width Wn of the second removal pattern 26c is not limited. For example, when it is used for a cross line as shown in FIG. 12B, it can be configured to satisfy 8 μm ≦Wn ≦ 30 μm. Further, the relationship between the line width Wn of the second removal pattern 26c and the line width Wq of the device pattern 25b is preferably 1.0 ≦ Wn / Wq ≦ 1.5, more preferably 1.0 ≦ Wn / Wq ≦ 1.2.

Fig. 13A is a black matrix composed of a linear device pattern 27a extending in the Y direction and a linear device pattern 27b having a line width Wq (Wq > Wp) extending in the X direction. In order to form the device pattern as shown in FIG. 13A, the photomask shown in FIG. 13B has a linear first line 1b of the line width Wm extending in the Y direction and a line width Wn extending in the X direction (Wn>Wm). The linear second removal pattern 28c. The photomask shown in Fig. 13B has a light shielding portion 28a, a first removal pattern 28b composed of a semi-transmissive portion, and a second removal pattern 28c composed of a light transmission portion.

Next, a method of manufacturing the photomask of the present embodiment will be described.

Fig. 14 is a view for explaining a method of manufacturing the first photomask of the embodiment.

First, as shown in FIG. 14(a), a light-shielding film 32 and a photoresist film 33 are sequentially formed on the transparent substrate 31 as a blank mask 30 of an optical film.

As the transparent substrate 31, for example, a substrate transparent to exposed light such as synthetic quartz, soda lime glass, or alkali-free glass can be used.

As the light shielding film 32, chromium or a compound thereof can be used. For example, the light shielding film 32 can be a laminated film of a chromium nitride film, a chromium carbide film, a chromium carbide oxide film, a chromium oxide film, a chromium oxide nitride film, or the like.

Alternatively, as the light shielding film 32, a metal halide can be used. For example, as the light shielding film 32, an oxide, a nitride, or an oxynitride of molybdenum telluride, antimony telluride, titanium telluride, tungsten telluride, or the like can be used. Further, the molybdenum molybdenum-based film used for the light-shielding film 32 may be, for example, a MoxSiy film, a MoSiO film, a MoSiN film, a MoSiON film, or the like.

Then, as shown in FIG. 14(b), the blank mask 30 is patterned by laser or electron beam using a drawing device to expose the photoresist film 33. The drawing data is used to form a shading portion.

Then, as shown in FIG. 14(c), the developer is supplied to the photoresist film 33 for development, and a photoresist pattern 33a covering a predetermined region where the light shielding portion is formed is formed.

Then, as shown in FIG. 14(d), the photoresist pattern 33a is used as a mask to etch the light-shielding film. 32. A light shielding film pattern 32a is formed. For the etching of the light-shielding film 32, wet etching using a well-known etchant can be applied. For example, if the light shielding film 32 contains chromium or a compound thereof, an etchant for chromium (for example, cerium ammonium nitrate or perchloric acid) may be used. When the light shielding film 32 contains a telluride, a fluorine-based etchant can be used.

Then, as shown in FIG. 14(e), after the photoresist pattern 33a is peeled off, the semi-transmissive film 34 is formed on the entire surface of the transparent substrate 31 on which the light-shielding film pattern 32a is formed. The semi-transmissive film 34 determines the desired transmittance and the amount of phase shift when necessary, and forms a film with an appropriate film thickness.

As the semi-transmissive film 34, a film made of a chromium compound or a metal halide can be used. For example, as the chromium compound film used as the semi-transmissive film 34, a chromium nitride film, a chromium carbide film, a chromium carbide oxide film, a chromium oxide film, a chromium oxide nitride film, or the like can be exemplified.

In addition, as the metal hydride film used as the semi-transmissive film 34, a bismuth molybdenum film, a bismuth telluride film, a titanium telluride film, a tungsten telluride film, or the like, an oxide film, a nitride film, or an oxynitride may be mentioned. Membrane and the like. Further, the molybdenum molybdenum-based film used for the semi-transmissive film 34 may be, for example, a MoxSiy film, a MoSiO film, a MoSiN film, a MoSiON film or the like.

In the case where the etching selectivity of the semi-transmissive film 34 and the light-shielding film 32 is required according to the method of manufacturing the photomask, it is preferable to use a combination of a chromium-based film and a germanide-based film.

In the step shown in Fig. 14 (e), the transfer pattern of the photomask shown in Figs. 10B, 10C, and 11B can be formed. That is, the device pattern 22 (24) for forming Wp (Wp < 10 μm) on the object to be transferred can be manufactured by the above steps and has a line width Wm (1 ≦ (Wm - Wp) / 2 ≦ 4 (μm) a light-shielding of the first removal pattern 23b formed by the light-transmitting portion or a first removal pattern having a semi-transmissive portion having a line width Wm (1 ≦ (Wm - Wp) / 2 ≦ 4 (μm)) Photomask of 23c (24b).

On the other hand, in the case where the transfer pattern has a removal pattern of the line width Wn (Wn>Wm) as shown in FIGS. 12B and 13B, the following steps are further carried out.

As shown in FIG. 14(f), a photoresist film 35 is formed on the entire surface of the blank mask having the light shielding film pattern 32a and the exposed semi-transmissive film 34. Then, the blank mask 30a on which the photoresist film 35 is formed is patterned by laser or electron beam using a drawing device to expose the photoresist film 35. The drawing data is used to form a light transmitting portion.

Then, as shown in FIG. 14(g), the developer is supplied to the photoresist film 35 for development, and a photoresist pattern 35a covering the light-transmitting portion and not forming a predetermined region is formed.

Then, as shown in FIG. 14(h), the semi-transmissive film 34 is etched by using the photoresist film pattern 35a as a mask to form a semi-transmissive film pattern 34a.

Finally, as shown in FIG. 14(i), by removing the photoresist pattern 35a, a removal pattern other than the removal pattern of the line width Wm and having a line width Wn (Wn > Wm) formed by the light transmitting portion can be manufactured. Photomask.

The method of manufacturing the first photomask shown in FIG. 14 is an example in which etching selectivity is used between the semi-transmissive film 34 and the light-shielding film 32. However, even if there is no etching selectivity between the semi-transmissive film 34 and the light-shielding film 32, that is, with respect to etching of either of the semi-transmissive film 34 and the light-shielding film 32, the resistance of the other film is low. In the case of the case, the manufacturing method of the first photomask can also be applied. In this case, the following aspects must be considered: depending on the alignment deviation of the 2 drawing steps, the pattern size may be affected.

Further, the transmittance of the semi-transmissive film 34 is preferably 20 to 60%. Further, for example, in the case where the transfer pattern has a light-shielding portion, a semi-transmissive portion, and a light-transmitting portion as shown in FIG. 13B, the light-transmitting portion and the semi-transmissive portion may be adjacent to each other. In this case, depending on the selected semi-transmissive film 34, interference may occur at the boundary with the light-transmitting portion due to the phase difference of the transmitted light, thereby forming an undesired dark portion. Therefore, it is preferable to select the material and film thickness of the semi-transmissive film 34 so that the phase difference of the transmitted light between the adjacent light-shielding portion and the semi-transmissive portion is 90 degrees or less, more preferably 60 degrees or less. .

Next, a method of manufacturing a photomask different from the method of manufacturing the first photomask will be described. Fig. 15 is a view for explaining a method of manufacturing the second photomask of the embodiment.

First, as shown in FIG. 15(a), a blank mask 40 in which the semi-transmissive film 42, the light-shielding film 43, and the photoresist film 44 are sequentially formed on the transparent substrate 41 is prepared. As described above, the second photomask manufacturing method is different from the method of manufacturing the first photomask in that the semi-transmissive film 42 is formed on the transparent substrate 41.

Then, as shown in FIG. 15(b), the blank mask 40 is imaged by laser or electron beam using a drawing device to expose the photoresist film 44. The drawing data is used to form a shading portion.

Then, as shown in FIG. 15(c), the developer is supplied to the photoresist film 44 for development, and a photoresist film 44a covering a predetermined region where the light shielding portion is formed is formed.

Then, as shown in FIG. 15(d), the light-shielding film 43 is etched by using the photoresist pattern 44a as a mask to form the light-shielding film pattern 43a.

Then, as shown in FIG. 15(e), the photoresist pattern 44a is peeled off.

Further, when the transfer pattern has a removal pattern of the line width Wn (Wn > Wm), the following steps are carried out.

As shown in Fig. 15 (f), a photoresist film 45 is formed on the entire surface of the blank mask having the semi-transmissive film 42 and the light-shielding film pattern 43a. Then, the blank mask 40a on which the photoresist film 45 is formed is patterned by laser or electron beam using a drawing device to expose the photoresist film 45. The drawing data is used to form a light transmitting portion.

Then, as shown in Fig. 15 (g), the developer is supplied to the photoresist film 45 for development, and a photoresist pattern 45a covering the predetermined region of the light-transmitting portion is formed.

Then, as shown in FIG. 15(h), the semi-transmissive film 42 is etched by using the photoresist film pattern 45a as a mask to form a semi-transmissive film pattern 42a.

Finally, as shown in FIG. 15(i), by peeling off the photoresist pattern 45a, it is possible to manufacture the line width Wn (Wn>Wm) which is formed by the light transmitting portion in addition to the first removal pattern of the line width Wm. 2 Remove the mask of the pattern.

In the manufacturing method of the second photomask shown in FIG. 15, the semi-transmissive film 42 and the light shielding film 43 are used. Between the use of materials with etch selectivity. Further, the film thickness of the semi-transmissive film 42 must be determined in advance in accordance with the transmittance to be obtained, and then film formation is performed.

Next, a pattern transfer method using a photomask according to the present embodiment will be described.

In the pattern transfer method of the present embodiment, a negative-type photosensitive material film formed on the transfer target is exposed using a photomask having a transfer pattern, and a line width Wp is formed on the transfer target. The first device pattern. For example, using such a pattern transfer method, a black matrix in a display device can be manufactured.

In this case, the pattern transfer method uses a mask to form a device pattern having a line width Wp on the transfer target, and the mask includes a light-shielding region having at least a light-shielding film formed on the transparent substrate, and a light-shielding region. a transfer pattern that is disposed so as to correspond to the first removal pattern of the line width Wm of the device pattern, and has a main surface having a side of 300 mm or more. In the pattern transfer method, the line width Wp of the device pattern is used. The relationship with the line width Wm of the first removal pattern satisfies the following formulas (1) and (2), and a transfer method in which transfer is performed by applying appropriate exposure conditions, and the pattern can be transferred.

Wp<10μm...(1)

1≦(Wm-Wp)/2≦4(μm)...(2)

The photomask of the present embodiment is preferably a proximity exposure for setting the close gap to a range of 10 to 200 μm. The contact gap is preferably in the range of 30 to 150 μm, and more preferably in the range of 60 to 150 μm. Further, even when the close gap is different depending on the in-plane position of the transfer target, that is, when there is unevenness in the plane, the contact gap is preferably within the above range at any position in the plane.

Here, the effect of the present invention is remarkable when the distribution of the proximity distance in the in-plane, that is, the difference between the maximum value and the minimum value of the proximity distance is in the range of 30 μm to 100 μm. That is, the mask of the present embodiment is useful in a system in which the distribution of the close gaps in the plane is uneven.

When the transfer pattern of the photomask of the embodiment is designed, the transfer is performed on the transfer target In the case of the device pattern, even in the presence of a close gap, the light intensity unevenness of the exposed light thus generated can be suppressed, and the in-plane CD distribution is preferably the target CD ± 10%, or the CD is not more than 1 μm.

For example, referring to FIG. 20A, FIG. 20B, and FIG. 20C, when the close gap is changed from 70 μm to 130 μm and the distribution close to the gap is 60 μm (see FIG. 20A ), the CD is not suppressed to 0.9 μm or less (refer to FIG. 20B ). ). In Fig. 21B, CDs are not all 0.8 μm or more, and in Fig. 22B, CDs are not all 0.7 μm or less (wherein the CD of the light intensity distribution).

(Example)

In order to confirm the transfer property of the photomask according to the embodiment of the present invention, optical simulation was carried out using the mode shown in FIG.

Fig. 16A shows a photomask (binary mask) 50 having a light transmitting portion. The photomask 50 has a light shielding portion 50a and a removal pattern 50b composed of a light transmission portion having a line width Wm. Further, Fig. 16B shows a photomask (halftone mask) 51 having a semi-transmissive portion. The photomask 51 has a light shielding portion 51a and a removal pattern 51b composed of a semi-transmissive portion having a line width Wm.

(Comparative example)

In the mask 50 shown in FIG. 16A, when the line width Wp of the device pattern to be formed on the transfer target is 5 μm, and the line width Wm of the removal pattern 50b in the mask 50 is 5 μm. That is, when the deviation β is set to zero, the gap is changed close to the gap, and the peak of the CD fluctuation and the light intensity is obtained. Here, the case where the target CD is obtained in this value is taken as a reference to the case where the gap is close to 100 μm.

Fig. 17A is a graph showing a light intensity distribution formed on a transfer target. In Fig. 17A, the horizontal axis represents the position on the photomask, and the vertical axis represents the light intensity. The gap was changed between 5 μm and the gap between 70 μm and 130 μm. In Fig. 17A, a curve 170a indicates a curve close to a gap of 70 μm, a curve 170b indicates a curve close to a gap of 130 μm, and a curve 170c indicates a curve close to a gap of 100 μm.

Figure 17B is a graph showing the relationship between the close gap and the CD of the pattern to be formed. In Fig. 17B, the horizontal axis indicates close proximity to the gap, and the vertical axis indicates CD [μm]. Further, Fig. 17C is a graph showing the relationship between the light intensity close to the gap and the peak. In Fig. 17C, the horizontal axis represents the close gap and the vertical axis represents the light intensity.

As shown in Fig. 17B, when the proximity is changed from 70 μm to 130 μm, that is, a CD variation of about 2.3 μm occurs during a period of variation of 60 μm. Further, as shown in Fig. 17C, when the close gap is changed from 70 μm to 130 μm, that is, a variation in light intensity of a peak of 0.35 unit (relative value) occurs in a variation of 60 μm.

(Example 1)

In the photomask 50 shown in FIG. 16A, the line width Wp of the device pattern to be formed on the transfer target is set to 5 μm in the same manner as in the comparative example, and the photomask 50 is removed in this state. The line width Wm of the pattern 50b was set to 6 μm and 7 μm, and the same simulation was performed. That is, the values of the deviation β are 0.5 μm and 1.0 μm, respectively, and Wm/Wp are 1.2 and 1.4, respectively.

The results of the simulation are shown in Figs. 18A and 18B. Fig. 18A is a graph showing the relationship between the close gap and the CD. In Fig. 18A, the horizontal axis indicates close proximity to the gap, and the vertical axis indicates CD [μm]. Further, Fig. 18B is a graph showing the relationship between the light intensity close to the gap and the peak. In Fig. 18B, the horizontal axis represents the close gap and the vertical axis represents the light intensity.

In Figs. 18A and 18B, a curve 180a indicates a line width Wm of the removal pattern 50b of 5 μm, a curve 180b indicates a line width of the removal pattern 50b of 6 μm, and a curve 180c indicates that the line width of the removal pattern 50b is 7 μm curve.

As shown in FIG. 18A, in the curves 180b and 180c, both generate CD variations of about 1 μm. As shown in Fig. 18B, the larger the value of the deviation β, the greater the intensity of the light of the peak close to the gap. In particular, in the curve 180c in which the line width is set to 7 μm, the light intensity is greatly increased as compared with the comparative example shown by the curve 180a. The increase in light intensity is advantageous in sufficiently producing a crosslinking reaction of a negative photosensitive material.

(Example 2)

The difference from the reticle 50 in the case of using the reticle 51 shown in Fig. 16B will be discussed.

Fig. 19 is a graph showing the light intensity distribution formed on the object to be transferred. In Fig. 19, the horizontal axis represents the position on the photomask, and the vertical axis represents the light intensity. In Fig. 19, a curve 190a indicates a comparative example. The curve 190b is shown in the mask 51 shown in Fig. 16B, and the line width Wp of the device pattern to be formed on the transfer target is set to 5 μm, and the line width Wm of the removal pattern 51b in the mask 51 is set to 8 μm, and the curve when the transmittance of the semi-transmissive film constituting the removal pattern 51b is 55%. Thereby, the peak intensity of the light intensity distribution indicating the curve 190a of the comparative example and the curve 190b is made equal.

As shown in Fig. 19, in the present embodiment 2 (curve 190b) using a halftone mask, the peak shape is more pronounced than the binary mask (curve 190a) when the same peak intensity is obtained. That is, according to the second embodiment, not only a finer pattern can be formed, but also the inclination angle of the light intensity is large and close to vertical. This means that, when actually used for transfer, the cross-sectional shape of the edge portion of the obtained photoresist pattern is close to vertical, and it is shown to have an excellent effect of improving the processing accuracy in the subsequent step. In other words, it is understood that it contributes to the stability of the performance of the final product such as a display device and the improvement of the yield of the semi-finished product such as a color filter.

(Example 3)

According to the result of the embodiment 2, in the reticle 51 shown in Fig. 16B, the line width of the pattern of the device to be formed on the transfer target is set to 5 μm, and the line width of the removal pattern 51b in the reticle 51 is set. When it is set to 7 μm and the transmittance of the semi-transmissive film is 55%, the gap is changed close to the gap, and the peak of CD fluctuation and light intensity is obtained. Here, the case where the target CD is obtained in this value is taken as a reference to the case where the gap is close to 100 μm.

Fig. 20A is a graph showing a light intensity distribution formed on a transfer target. In Fig. 20A, the horizontal axis represents the position on the photomask, and the vertical axis represents the light intensity. The gap was changed between 5 μm and the gap between 70 μm and 130 μm. In Fig. 20A, a curve 200a indicates a curve close to a gap of 70 μm, a curve 200b indicates a curve close to a gap of 130 μm, and a curve 200c indicates a curve close to a gap of 100 μm.

Figure 20B is a graph showing the relationship between the close gap and the CD of the pattern to be formed. In Fig. 20B, the horizontal axis indicates close proximity to the gap, and the vertical axis indicates CD [μm]. Further, Fig. 20C is a graph showing the relationship between the light intensity close to the gap and the peak. In Fig. 20C, the horizontal axis represents the close gap and the vertical axis represents the light intensity.

As shown in FIG. 20B, when the close gap was changed from 70 μm to 130 μm, the CD variation was less than 1 μm during the period of variation of 60 μm. Further, as shown in FIG. 20C, when the close gap is changed from 70 μm to 130 μm, that is, a variation of 60 μm, a light intensity variation of a peak of 0.25 unit (relative value) is generated.

(Example 4)

The line width of the removal pattern 51b in the photomask 51 was set to 8 μm, and the same simulation as in the third embodiment was performed.

Fig. 21A is a graph showing a light intensity distribution formed on a transfer target. In Fig. 21A, the horizontal axis represents the position on the reticle, and the vertical axis represents the light intensity. The gap was changed between 5 μm and the gap between 70 μm and 130 μm. In Fig. 21A, a curve 210a indicates a curve close to a gap of 70 μm, a curve 210b indicates a curve close to a gap of 130 μm, and a curve 210c indicates a curve close to a gap of 100 μm.

Figure 21B is a graph showing the relationship between the close gap and the CD of the pattern to be formed. In Fig. 21B, the horizontal axis indicates close proximity to the gap, and the vertical axis indicates CD [μm]. Further, Fig. 21C is a graph showing the relationship between the light intensity close to the gap and the peak. In Fig. 21C, the horizontal axis represents the close gap and the vertical axis represents the light intensity.

As shown in Fig. 21B, when the close gap was changed from 70 μm to 130 μm, that is, during the period of variation of 60 μm, the CD variation was further reduced to less than 0.8 μm. Further, as shown in Fig. 21C, the light intensity of the peak is increased as compared with the third embodiment.

(Example 5)

The line width Wm of the removal pattern 51b in the photomask 51 was set to 9 μm, and the same simulation as in the third embodiment was performed.

Fig. 22A is a graph showing a light intensity distribution formed on a transfer target. In the picture In 22A, the horizontal axis represents the position on the reticle, and the vertical axis represents the light intensity. The gap was changed from 5 μm to from 130 μm to 130 μm. In Fig. 22A, a curve 220a indicates a curve close to a gap of 70 μm, a curve 220b indicates a curve close to a gap of 130 μm, and a curve 220c indicates a curve close to a gap of 100 μm.

Fig. 22B is a graph showing the relationship between the close gap and the CD of the pattern to be formed. In Fig. 21B, the horizontal axis indicates close proximity to the gap, and the vertical axis indicates CD [μm]. Moreover, Fig. 22C is a graph showing the relationship between the light intensity close to the gap and the peak. In Fig. 22C, the horizontal axis indicates the close gap and the vertical axis indicates the light intensity.

As shown in Fig. 22B, when the close gap was changed from 70 μm to 130 μm, that is, during the period of variation of 60 μm, the CD variation was further reduced to less than 0.7 μm. Further, as shown in Fig. 22C, the light intensity of the peak is increased as compared with the fourth embodiment.

According to the above, it is understood that the removal pattern of the reticle necessary for forming the pattern of the fine width on the transfer target is set to be larger than the line width, and the amount of light reaching the transfer target can be adjusted. Further, by adjusting the amount of deviation (β), and further preferably adjusting the deviation rate Wm/Wp, CD unevenness of the transfer pattern with respect to the unevenness of the close gap can be effectively suppressed. This aspect is of great significance especially in mass production.

Further, this effect is due to the use of a pattern which is a mask removal pattern, and the light intensity variation due to the proximity exposure gap can be reduced by using a pattern having a larger line width than the target line width formed on the object to be transferred. Further, since the light intensity of the transmitted light is appropriately adjusted by using a semi-transmissive film for the removal pattern of the reticle, exposure is performed, whereby the effect of suppressing line width unevenness due to the exposure gap is obtained.

According to the present invention, the pattern of the fine width can be formed without depending on a technique such as a projection exposure apparatus for semiconductor manufacturing or a phase shift mask.

Furthermore, the present invention is not limited to the above embodiment, and various modifications can be made. In the above-described embodiments, the size, shape, and the like as illustrated in the drawings are not limited thereto, and may be appropriately changed within the scope of the effects of the present invention. In addition, as long as it does not deviate from the present invention The scope of the purpose can be appropriately implemented.

For example, the present invention is not limited to a black matrix or a black stripe, and can be applied to a photo spacer (PS) or the like of a liquid crystal display device. In this case, the removal pattern of the above embodiment has a different shape such as a hole pattern, but does not hinder the effects of the present invention.

10‧‧‧Photomask

10a‧‧‧Transparent substrate

10b‧‧‧ shading area

10c‧‧‧1st removal pattern

11a‧‧‧Transferred body

11b‧‧‧1st device pattern

Wm‧‧‧ line width

Wp‧‧‧ line width

Claims (10)

A photomask comprising a transfer pattern for forming a device pattern of a line width Wp on a transfer target, and having a main surface having one side of 300 mm or more, and the transfer pattern includes a light-shielding region formed by forming at least a light-shielding film on the transparent substrate; and a first removal pattern disposed so as to be surrounded by the light-shielding region, and having a line width of Wm corresponding to the device pattern; and the device pattern The relationship between the line width Wp and the line width Wm of the first removal pattern described above satisfies the following equations (1) and (2): Wp < 10 μm (1) 1 ≦ (Wm - Wp) / 2 ≦ 4 (μm)...(2). The photomask of claim 1, wherein the first removal pattern comprises a light transmissive portion exposed on a surface of the transparent substrate. The photomask of claim 1, wherein the first removal pattern comprises a semi-transmissive portion on the transparent substrate to form a semi-transmissive film. The photomask of claim 3, wherein the light transmittance of the semi-transmissive film is 20 to 60%. The photomask according to any one of claims 1 to 4, wherein the transfer pattern includes a plurality of the first removal patterns having a line shape having a line width Wm, and the first removal pattern adjacent to the width direction The portion containing the above-mentioned light-shielding region having a width (3 × Wm) or more is included. The photomask according to any one of claims 1 to 4, wherein the transfer pattern further includes a second removal pattern having a line width Wn (Wn > Wm), and the second removal pattern includes a light transmission portion. The reticle according to any one of claims 1 to 4, wherein the reticle is a reticle for use in proximity exposure in a range of 10 to 200 μm. A manufacturing method of a photomask, comprising: a transfer pattern for forming a device pattern of a line width Wp on a transfer target, and the method of manufacturing the photomask comprises the steps of: transparent substrate Forming a blank mask having an optical film including at least a light-shielding film thereon, performing a photolithography step on the optical film, and forming the transfer pattern by patterning including wet etching; The printing pattern includes a light-shielding region formed by forming at least a light-shielding film on the transparent substrate, and a first removal pattern disposed so as to be surrounded by the light-shielding region, and having a line width of Wm corresponding to the device pattern; The relationship between the line width Wp of the device pattern and the line width Wm of the first removal pattern satisfies the following equations (1) and (2): Wp < 10 μm (1) 1 ≦ (Wm - Wp) / 2≦4(μm)...(2). A pattern transfer method for forming a device pattern of a line width Wp on a transfer target by a proximity exposure using a photomask including a transfer pattern, and using the request 1 A photomask manufactured by any one of the seventh, or a photomask manufactured by the method of manufacturing a photomask according to claim 8, wherein a proximity exposure device is used for the negative photosensitive material film formed on the transfer target Exposure. A method of manufacturing a display device, characterized in that a pattern transfer method as in claim 9 is used.