TW201725444A - Method of manufacturing a photomask, photomask, and method of manufacturing a display device - Google Patents

Abstract

To provide a method of manufacturing a photomask which is finer and which is high in both CD accuracy and transmittance accuracy. A method of manufacturing a photomask having a transfer pattern formed on a transparent substrate is provided. The transfer pattern includes a transparent section and first and second transmission control sections. The method includes a step of preparing a photomask blank provided with a first thin film which is formed on the transparent substrate and which has a predetermined transmittance for exposure light, a first patterning step of etching the first thin film to form a first thin film pattern, and a second patterning step of forming a second thin film on the transparent substrate with the first thin film pattern formed thereon and etching the second thin film to form a second thin film pattern. In the second patterning step, only the second thin film is etched.

Description

Photomask manufacturing method, photomask, and display device manufacturing method

The present invention relates to a multi-step mask useful for the manufacture of a display device typified by a liquid crystal panel or an organic EL panel, a method of manufacturing the same, and a method of manufacturing a display device using the multi-step mask.

In recent years, display devices such as liquid crystal panels or organic EL panels have been increasingly required to be further miniaturized, and in the pattern for manufacturing such photomasks, the tendency to refine is also remarkable. In particular, it is desirable that the reason for miniaturization of the display device is not only from the viewpoint of increasing the image density such as an increase in the pixel density, an increase in the brightness of the display, and an increase in the reaction speed, but also from the viewpoint of energy saving. Favorable aspect. Moreover, with such a trend of miniaturization, the quality requirements for the photomask are gradually increasing. Heretofore, a multi-step mask (gray scale mask) having a transfer pattern formed by patterning each of a light-shielding film and a semi-transmissive film formed on a transparent substrate has been known. This multi-step mask is effectively used in the manufacture of a display device or the like. For example, Patent Document 1 listed below discloses a halftone film type gray scale mask and a method of manufacturing the same. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-257712

[Problems to be Solved by the Invention] The multi-step mask has three or more portions having different light transmittances, which are called a light-shielding portion, a light-transmitting portion, and a semi-transmissive portion, in the transfer pattern. A resist pattern having a plurality of residual film thicknesses is formed on the transfer target. This resist pattern is used as an etching mask for processing a film formed on a transfer target. In this case, after the first etching, the second etching is performed by the thin film resist pattern, and the resist pattern functions as an etching mask having a different shape in the first etching and the second etching. Therefore, the multi-step mask can also be referred to as a photomask having a function equivalent to a plurality of masks. Therefore, it is mainly used as a number of photomasks necessary for reducing the manufacture of the display device, which contributes to an improvement in production efficiency. The multi-step mask has a semi-transmissive portion using a semi-transmissive film that partially transmits the exposure light, in addition to the light shielding portion and the light transmitting portion. By appropriately controlling the light transmittance of the semi-transmissive portion or the phase characteristics with respect to the transmitted light, the thickness of the resist pattern formed on the transfer target, or the cross-sectional shape thereof, or the like can be changed. Further, the multi-step mask of Patent Document 1 has a transfer pattern in which a plurality of patterned sheets (such as a light-shielding film or a semi-transmissive film) are laminated. In such a multi-step mask, by setting a desired transmittance or phase characteristic corresponding to light used for exposure, selecting a film material or film thickness suitable for the film, and adjusting film forming conditions, there is a design that can be designed to have The advantages of a multi-order mask of desirable light characteristics. Here, the method described in Patent Document 1 of the prior art will be described. In the method described in Patent Document 1, the gray scale mask 200 shown in Fig. 3(i) is produced by the procedure described in Fig. 3. Specifically, first, a light-shielding film 102 is formed on the transparent substrate 101, and a positive resist is applied thereon to form a mask blank 100 of the resist film 103 (see FIG. 3(a)). Then, it is drawn (first drawing) and developed using a laser drawing machine or the like. Thereby, the resist film is removed in the region where the semi-transmissive portion is formed (the region A in FIG. 3). As a result, in the region where the light shielding portion is formed (the region B in FIG. 3) and the region where the light transmitting portion is formed (the region C in FIG. 3), the resist pattern 103a in which the resist film remains is formed (see FIG. 3(b)). . Next, the formed resist pattern 103a is used as a mask, and the light shielding film 102 is etched (first etching), and the light shielding film pattern 102a is formed in a region corresponding to the light shielding portion (B region) and the light transmitting portion (C region) (refer to Figure 3 (c)). Thereafter, the resist pattern 103a is removed (see FIG. 3(d)). The region corresponding to the semi-transmissive portion (A region) is defined by the first photolithography step described above. Next, the semi-transmissive film 104 is formed on the entire surface of the substrate having the light-shielding film pattern obtained above (see FIG. 3(e)). Thereby, the semi-transmissive portion of the A region is formed. Further, a positive resist is applied to the entire surface of the semi-transmissive film 104 to form a resist film 105 (see FIG. 3(f)), and is depicted (second drawing). After the development, the resist film 105 is removed in the light-transmitting portion (C region), and a resist pattern 105a in which a resist film remains is formed in the light-shielding portion (B region) and the semi-transmissive portion (A region) (refer to FIG. 3). (g)). This is used as a mask, and the semi-transmissive film 104 and the light-shielding film pattern 102a which are the C regions of the light-transmitting portion are removed by etching (second etching) (see FIG. 3(h)). Here, continuous etching can be performed by the same or similar etching characteristics of the semi-transmissive film and the light-shielding film. Then, after the second etching, the resist pattern 105a is removed to complete the gray scale mask 200 (see FIG. 3(i)). According to the method described above, the light-shielding film and the semi-transmissive film are respectively patterned by the secondary photolithography step (drawing, development, etching), and the light-shielding portion, the light-transmitting portion, and the semi-transmissive portion are provided. Grayscale reticle. However, in a display device equipped with a liquid crystal or an organic EL, an improvement in technology is required in many aspects such as brightness, sharpness, reaction speed, power consumption reduction, and cost reduction. Under such circumstances, in addition to delicately forming a pattern which is finer than the previous one, it is required to transfer the pattern to the object to be transferred (panel substrate, etc.) at a low cost. Features. Moreover, the arrangement of the transfer pattern required is also diverse and complicated. Under such circumstances, the following new problems were discovered by the inventors' research. According to the procedure of Patent Document 1, in the second etching, two films of the semi-transmissive film and the light-shielding film are continuously removed in one step (see FIG. 3(h)). Here, for example, the light-shielding film is a film mainly composed of chromium, and the semi-transmissive film contains a chromium compound. Further, the etching time of the former light-shielding film is X (for example, 50 seconds), and the etching time of the latter semi-transmissive film is Y (for example, 10 seconds). In this case, in the second etching, an etching time of X + Y (for example, 60 seconds) is required, which is longer than the case of etching a single film of a light shielding film or a semi-transmissive film. Further, here, as the etching method, wet etching is used. Wet etching can be used extremely advantageously for a photomask for display device manufacturing. This is because the mask for the manufacture of a display device having a large area (for example, 300 mm or more on one side) and having substrates of various sizes is wet-etched compared to a dry etching which requires a vacuum device, which is very important for equipment or efficiency. advantageous. Further, the wet etching is highly conductive, and etching is performed not only in the depth direction of the film to be etched but also in the direction parallel to the surface of the film to be etched (side etching). In general, in the case where a long etching time is required, since the in-plane unevenness of the etching amount tends to increase, the amount of side etching increases as the time of wet etching becomes longer, and unevenness in the amount of the amount Also increased. Therefore, in the second etching, the line width or the size of the transfer pattern (CD: Critical Dimension) is formed by continuously etching and removing the two films of the semi-transmissive film and the light-shielding film in one step. ), the following is used in the sense of the line width or size of the pattern.) Accuracy is easily deteriorated. That is, the second etching of X + Y (seconds) is required, and there is a problem at this point. Further, as the etching time becomes longer, the amount of the etchant used also increases, and the burden of disposal of the waste liquid containing heavy metals also increases. Further, the inventors of the present invention have focused on the case where the design of the transfer pattern is complicated or has a pattern of a fine size (CD), and further, the possibility of the following problems arises. In Fig. 3(i) showing the method of Patent Document 1, although a pattern including a portion in which the semi-transmissive portion and the light-shielding portion are adjacent is formed, in addition to such a pattern, a mask for the manufacture of a display device has recently been used. The transfer pattern contains more complicated ones. For example, there is a need for a transfer pattern having a portion in which the light transmitting portion and the semi-light transmitting portion are adjacent to each other in addition to the adjacent portion. Therefore, for example, it is considered that the transfer pattern shown in FIG. 3 described above further has a portion in which the light transmitting portion and the semi-light transmitting portion are adjacent to each other (see FIG. 4(i)). 4(f) to (i) (the second photolithography step) correspond to FIGS. 3(f) to (i), respectively. Here, in the step of displaying FIG. 4(h) of the second etching, as in the above-described step of FIG. 3(h), there is a portion (N) in which the semi-transmissive film 104 and the light-shielding film pattern 102a are continuously etched and removed. Therefore, the etching time is lengthened due to the deep etching depth, and the amount of side etching is also increased depending on the etching depth. As a result, the formed pattern size (CD) is likely to vary, and the distribution of the CD error in the plane is also likely to increase (see FIG. 4(h')). Further, in the step of FIG. 4(h), a portion (N) for continuously etching away the semi-transmissive film 104 and the light-shielding film pattern 102a and a portion (K) for etching only the semi-transmissive film 104 are removed. At this time, it is difficult to set the time required for the second etching. Since the etching time of T (seconds) is required in the part of (K) of the latter, an etching time equivalent to T + α (second) is required in the portion of N of the former. Therefore, in the step of FIG. 4(h), in practice, when the etching of the portion of N is completed, the etching is excessively performed in the portion of K, and the semi-transmissive film 104 under the resist pattern 105a is side-etched ( Refer to Figure 4 (h')). Further, as a result, the size of the semi-transmissive film pattern 104a formed is smaller than the size of the resist pattern 105a in the portion of K, and becomes smaller (W), which is deviated in the pattern size (CD), and is in-plane. The distribution of CD errors is also likely to become large (refer to Fig. 4(i')). Moreover, for the semi-transparent film of such a multi-step mask, the management of the light transmittance is extremely important. In the prior art method of FIG. 3, when the semi-transmissive film is formed, it is already on the transparent substrate. There is a pattern containing a light shielding film. Therefore, it is not easy to measure the light transmittance of the semi-transmissive film formed. In particular, although the mask for manufacturing a display device has a large area (for example, a square shape of 300 mm or more), a large-sized device (sputtering device or the like) is also used for film formation, but the film-forming material is uniformly deposited in the surface. There are difficulties. For example, there is a distribution of film thickness in the plane by the relative position with the sputtering target or the like. When the film thickness is accurately measured and the tendency is accurately grasped, it is conceivable that the second etching (patterning of the light shielding film) by the manufacturing method of the present invention to be described later cancels the influence. However, in the prior art method described in FIG. 3, there is a problem that it is difficult to accurately measure the transmittance of the semi-transmissive film at each position in the plane. Therefore, in the method of the prior art known in Fig. 3, there is a problem in the case of manufacturing a multi-step mask having a finer, higher CD precision and higher transmittance precision. Accordingly, it is an object of the present invention to provide a method of manufacturing a photomask capable of producing a multi-step mask having a finer, higher CD accuracy and higher transmittance accuracy, a mask, and a display device using the same. method. [Means for Solving the Problems] As a result of the active discussion of the above problems, the inventors have found that the above problems can be solved by the invention having the following constitution until the completion of the present invention. That is, the present invention has the following constitution. (Configuration 1) A method of manufacturing a reticle, comprising: a method of manufacturing a reticle including a transfer pattern including a light transmitting portion, a first transmission control portion, and a second transmission control portion on a transparent substrate, and The method includes the steps of: forming a mask blank of a first film having a specific exposure light transmittance on the transparent substrate; and forming, by the first patterning step, the first film pattern by forming the first film; a second patterning step of forming a second thin film on the transparent substrate on which the first thin film pattern is formed, and forming a second thin film pattern by etching the second thin film, and in the second patterning step Only the second film described above is etched. (Configuration 2) The method of manufacturing a photomask according to the first aspect, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion has a portion where only the first thin film is formed on the transparent substrate, The second transmission control unit has a portion where only the second thin film is formed on the transparent substrate. (Configuration 3) The method for producing a photomask according to the first or second aspect, wherein the first thin film comprises a material resistant to an etchant of the second thin film. (Configuration 4) The method of manufacturing a photomask according to the first or second aspect, wherein the first thin film includes a material that is etched by the etchant of the second thin film. (Configuration 5) The method of manufacturing a photomask according to the fourth aspect, comprising: forming the first thin film on the transparent substrate on which the first thin film pattern is formed, after the first patterning step; The step of etching the termination film. (Configuration 6) The method of manufacturing a photomask according to the fifth aspect, comprising the step of removing the etching stop film of the light transmitting portion or the light transmitting portion and the first transmission control portion after the second patterning step . In a method of manufacturing a photomask according to any one of the first to sixth aspects, the first film is a semi-transmissive film that partially transmits exposure light. The method of manufacturing the reticle according to any one of the first to sixth aspect, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90. (Embodiment 9) The method of manufacturing a photomask according to any one of the first to sixth aspect, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90, and the light transmittance Tf(%) of the first transmission control unit satisfies 5≦Tf≦60. The method of manufacturing a reticle according to any one of the first to sixth aspect, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210. The method of manufacturing the reticle according to any one of the first to sixth aspect, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. (Aspect 12) The method of manufacturing a reticle according to any one of 1 to 11, wherein the second film is a semi-transmissive film that partially transmits exposure light. (Claim 13) The method of manufacturing a reticle according to any one of 1 to 11, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of exposure light transmitted through the light transmission portion (degree) meets 0< ≦90. The method of manufacturing a photomask according to any one of the first to eleventh aspect, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦80. The method of manufacturing a reticle according to any one of the first to eleventh aspect, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of exposure light transmitted through the light transmission portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The method of manufacturing a photomask according to any one of the first to eleventh aspect, wherein the second thin film is a light shielding film. (Configuration 17) The method of manufacturing a photomask according to claim 16, wherein a reflection reducing layer that reduces reflection of light is provided on a surface portion of the second film. In a method of manufacturing a photomask according to any one of the first to seventh aspect, the photomask blank has an additional constituent film and a resist film on the first film. (Configuration 19) The method for producing a photomask according to the configuration 18, wherein the adhesion between the additional constituent film and the resist film is higher than the adhesion between the first film and the resist film. (Configuration 20) The method of manufacturing a photomask according to 18 or 19, wherein before the first patterning step, a pre-patterning step of etching the additional constituent film to form an additional constituent film pattern, and the first pattern is formed In the chemical conversion step, the first constituent film pattern is used as a mask, and the first film is etched. (Configuration 21) The method of manufacturing a photomask according to claim 20, wherein the additional constituent film pattern is removed after the first patterning step and before the second patterning step. (Configuration 22) A method of manufacturing a photomask, comprising: a light transmitting portion, a first transmission control portion, and a second transmission control portion on a transparent substrate, and including the first transmission control portion and the second a method of manufacturing a mask for transferring a pattern adjacent to an adjacent portion of a control portion, comprising: a step of preparing a mask blank of a first film having a specific exposure light transmittance on the transparent substrate; a patterning step of forming a first resist pattern in a region of the first transmission control portion, forming a first thin film pattern by etching the first thin film, and a film forming step of forming the first thin film pattern a second thin film formed on the transparent substrate; and a second patterning step of forming a second resist pattern in the region of the second transmission control portion, and etching the second thin film to form a second thin film pattern; In the second patterning step, a laminated portion in which the second resist pattern and the first thin film pattern are laminated is formed in the adjacent portion, and only the second thin film is etched using the second resist pattern. (Configuration 23) The method of manufacturing a photomask according to the configuration 22, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion includes a portion where only the first thin film is formed on the transparent substrate, The second transmission control unit includes a portion where only the second thin film is formed on the transparent substrate. (Configuration 24) The method of manufacturing a photomask according to claim 22 or 23, wherein a width M1 of the laminated portion is in a range of 0.5 to 2 μm. (Configuration 25) A photomask comprising a photomask including a light transmitting portion, a first transmission control portion, and a transfer pattern of a second transmission control portion on a transparent substrate, and the transfer pattern a first film and a second film having a specific exposure light transmittance, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion is formed on the transparent substrate without forming the second film. The second transmission control unit is formed by forming at least the second thin film on the transparent substrate, and the boundary between the first transmission control unit and the second transmission control unit is not formed. The first film is etched into a cross section to form an etched cross section of the second film. (Configuration 26) The photomask according to the configuration 25, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion has a portion on which the first film is formed only on the transparent substrate, and the second transmission The control unit has a portion in which only the second thin film is formed on the transparent substrate. (Configuration 27) The photomask of 25 or 26, wherein the first film contains a material resistant to an etchant of the second film. (Configuration 28) The photomask of 25 or 26, wherein the first thin film includes a material etched by the etchant of the second thin film, and the second transmission control portion has an etching stopper film and the first 2 The film is laminated in this order. The reticle according to any one of the second aspect of the present invention, wherein the second transmission control unit has a layer of the first film and the second film adjacent to an edge portion of the first transmission control unit section. (Configuration 30) The reticle of the ninth aspect, wherein the width M2 of the laminated portion is in the range of 0.5 to 2 μm. The reticle of any one of 25 to 30, wherein the first film is a semi-transmissive film, and the second film is a light-shielding film. (Configuration 32) A photomask comprising a photomask including a light transmission portion, a first transmission control portion, and a transfer pattern of a second transmission control portion on a transparent substrate, wherein the transfer pattern includes a first film pattern composed of a first film having a specific exposure light transmittance and a second film pattern formed of a second film, wherein the light-transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control unit The transparent substrate has a portion in which only the first thin film pattern is formed, and the second transmission control unit has a portion in which only the second thin film pattern is formed on the transparent substrate, and is sandwiched between the first transmission control unit And a laminated portion of the first thin film pattern and the second thin film patterned layer in the second transmission control unit. (Configuration 33) The reticle of the configuration 32, wherein the width M2 of the laminated portion is in the range of 0.5 to 2 μm. (Configuration 34) The photomask of 32 or 33, wherein the edges of the first thin film pattern and the second thin film pattern each have a wet-etched cross section of the first thin film and the second thin film. The reticle of any one of 32 to 34, wherein the first film is a semi-transmissive film that partially transmits exposure light. The reticle of any one of 32 to 34, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90. The reticle of any one of 32 to 34, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The reticle of any one of 32 to 34, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210. The reticle of any one of 32 to 34, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion. (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The reticle of any one of 32 to 39, wherein the second film is a light shielding film. The reticle of any one of 32 to 39, wherein the second film is a semi-transmissive film that partially transmits exposure light. The reticle of any one of 32 to 39, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion. (degree) meets 0< ≦90. The reticle of any one of 32 to 39, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦80. The reticle of any one of 32 to 39, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The reticle of any one of 25 to 44, wherein the transfer pattern is a pattern for manufacturing a display device. (Configuration 46) A method of manufacturing a display device, comprising: preparing a photomask of any one of 25 to 44; and transferring the transfer pattern to a transfer target by using an exposure device . [Effects of the Invention] According to the present invention, in the etching step of each of the first film and the second film, since only the respective films are etched, the etching time is compared to the case where the plurality of laminated films are continuously etched. Since the setting is short, the pattern size (CD) variation due to the side etching can be reduced. In particular, if a single film is etched in all the etching steps, the time required for etching can be calculated by using the film quality and the film thickness in advance, so that the dimensional deviation caused by the side etching can be minimized. Further, according to the configuration of the reticle of the present invention, the design or management of the optical characteristics (for example, transmittance) of the first transmission control unit and the second transmission control unit is simpler and more accurate, thereby achieving high definition and energy saving. The manufacture of high-profile display devices is of great significance. That is, according to the present invention, it is possible to provide a method of manufacturing a photomask capable of producing a photomask having finer, higher CD precision, higher optical properties (light transmittance, etc.), and a photomask. Further, according to the present invention, by manufacturing the display device using the photomask, it is possible to manufacture a high-definition display device having high definition and high energy efficiency.

Hereinafter, the form of the present invention will be described in detail with reference to the drawings. [First Embodiment] The photomask manufacturing method of the present invention is a photomask including a transfer pattern including a light transmitting portion, a first transmission control portion, and a second transmission control portion, on the transparent substrate. A manufacturing method comprising: a step of preparing a photomask blank having a first thin film having a specific exposure light transmittance on the transparent substrate; and a first patterning step of etching the first thin film Forming a first thin film pattern; and forming a second thin film on the transparent substrate on which the first thin film pattern is formed, and forming a second thin film by etching the second thin film; In the second patterning step, only the second film is etched. In the first embodiment, the first transmission control unit serves as a light shielding unit as a semi-transmissive portion that transmits a part of the exposure light. Further, the first film is a semi-transmissive film, and the second film is a light-shielding film. Fig. 1 is a view showing the steps of a first embodiment of a method of manufacturing a photomask according to the present invention. Hereinafter, each step will be described in order. First, a mask blank (substrate with a semi-transmissive film) 10 having a semi-transmissive film 2 having a specific exposure light transmittance is formed on the transparent substrate 1 (see FIG. 1(a)). Here, as the transparent substrate 1, a transparent material containing quartz glass or the like is polished flat and smoothly. The transparent substrate used for the photomask for manufacturing a display device preferably has a square shape of 300 mm or more on one side of the main surface, and has a thickness of 5 to 13 mm. The semi-transmissive film 2 is formed on the main surface of one of the transparent substrates 1 by a known film forming method such as sputtering. In order to make the semi-transmissive film 2 have a desired transmittance with respect to the exposure light used in the exposure mask, the material and film thickness can be determined in advance. As the exposure light, for example, a light source including an i-ray, an h-ray, and a g-ray which are included in an exposure apparatus for liquid crystal can be used. Therefore, the reference of the transmittance can be used with respect to the light in the wavelength range, and can generally be described as a value relative to the representative wavelength (here, i-ray) included in the wavelength. Further, the light transmittance Tf of the semi-transmissive film 2 is preferably from 5 to 60% with respect to the i-ray (100% of the transparent substrate). Further preferably, it is 10 to 40%. Here, Tf is the light transmittance of the semi-transmissive film 2 used as described above. In general, when the semi-transmissive film 2 is formed with a fine pattern, the light transmittance and interference of the semi-transmissive portion are affected by the diffraction and interference of the light disposed in the surrounding light-shielding portion or the light-transmitting portion. The film is different. Here, the light transmittance Tf is a transmittance inherent to the film which is not affected by the diffraction or interference of the light of the surrounding pattern. For example, if the semi-transmissive film 2 has a laminated structure, the transmittance which is inherent to the laminate is obtained. . Further, the semi-transmissive film 2 can have a desired phase shifting action as a representative wavelength with respect to exposure light. As the multi-step mask, the semi-transmissive film 2 has a phase shift amount in consideration of forming a resist pattern having a plurality of residual film thicknesses on the transferred body. (degree) preferably satisfies 0< ≦90 degrees, and further preferably 5 满足 ≦ 60 degrees. Thereby, the phase difference generated between the formed portion of the semi-transmissive film 2 and the light transmitting portion becomes the above The range of (degrees). This is because the position of the semi-transmissive portion and the light-transmitting portion corresponding to the multi-step mask is prevented, and the formation of the unnecessary pattern of the resist pattern (in the case of the positive-type resist layer) is prevented. Of course, in order to control the shape of the resist pattern formed on the transfer target by the phase shift action, it may be 150 ≦. ≦ 210 degrees or 60 ≦ ≦ 120 degrees. The material of the semi-transmissive film 2 may be, for example, a film containing Si, Cr, Ta, Zr or the like, or may be selected from such oxides, nitrides, carbides, or the like. As the Si-containing film, a compound of Si (SiON or the like), a transition metal halide (such as MoSi), or a compound thereof can be used. Examples of the compound of MoSi include an oxide, a nitride, an oxynitride, a oxycarbonitride, and the like of MoSi. Further, in the case where the material of the semi-transmissive film 2 is a Cr-containing film, a compound of Cr (oxide, nitride, carbide, nitrogen oxide, nitrogen carbide, carbon oxynitride) can be used. Further, in the present embodiment, the semi-transmissive film 2 preferably has etching selectivity (etching characteristics) between the light-shielding films 5 to be described later. That is, the semi-transmissive film 2 is preferably resistant to the etchant of the light-shielding film 5 (in the present embodiment, by using wet etching, more specifically, an etching liquid). Here, the etching rate ratio between the etching liquid of the resistive semi-transmissive film 2 with respect to the light shielding film 5 and the light shielding film 5 is 1/50 or less, preferably 1/100 or less. From this point of view, when a film containing Cr is used for the light shielding film 5, an Si system (for example, a person including MoSi) can be used for the semi-transmissive film 2. Or, it can be the opposite. A known method and apparatus such as a sputtering method can be used for the film formation of the semi-transmissive film 2. The film thickness of the semi-transmissive film 2 can be determined in advance in order to have a desired transmittance for exposure light when the mask is exposed. Further, it is preferable to set an appropriate number of measurement points in the plane after the film formation of the semi-transmissive film 2, and to measure the light transmittance (absolute value and in-plane distribution) in advance. For the measurement, for example, a spectrophotometer can be used. The semi-transmissive film 2 after film formation has a tendency to cause a certain film thickness distribution due to the position of the main surface of the substrate due to the film forming apparatus or film forming conditions, so that the data obtained by the measurement can be stored. Use for the purpose of product warranty or for the purpose of mapping the subsequent steps. In this way, since the transmittance management of the semi-transmissive film is simpler and more accurate, the transmittance accuracy as a photomask can be improved. Next, a resist film 3 is formed on the surface of the prepared mask blank 10 to form a billet with a resist film. A specific pattern of 4 (first drawing) is drawn (see FIG. 1(b)). Further, if necessary, a surface treatment for improving the adhesion to the resist film 3 can be performed with respect to the surface of the semi-transmissive film 2. Further, in order to compensate for the adhesion between the semi-transmissive film 2 and the resist film, the constituent film may be further additionally disposed between the two. The adhesion between the constituent film and the resist film is higher than the adhesion between the semi-transmissive film and the resist film, and the material constituting the film can be selected. In other words, by arranging the constituent film, the adhesion between the resist film and the semi-transmissive film which are in direct contact with each other can be made good. The material constituting the film is added, and the adhesion to the resist film is higher than that of the semi-transmissive film and the resist film. For example, a Cr compound can be used. A known one such as a slit coater or a spin coater can be used for the coating of the resist film 3. Although any of the positive type and the negative type may be used as appropriate, here, an example in which a positive type is used will be described. The first patterning step is carried out. First, the resist film 3 formed by coating is drawn by drawing data based on a specific pattern using a drawing device. As the drawing device, there is a device using an electron beam or a laser, but for a mask for manufacturing a display device, laser drawing can be effectively used. Next, the resist film 3 thus drawn is developed to form a resist pattern 3a (first resist pattern) (see FIG. 1(c)). Next, the formed resist pattern 3a is used as an etching mask, and the semi-transmissive film pattern 2a is formed by wet etching (first etching) of the semi-transmissive film 2 (see FIG. 1(d)). Here, since the etching target is only the semi-transmissive film 2, the etching end point can be accurately set with reference to the etching rate which is grasped in advance. Then, the remaining resist pattern 3a is removed by peeling off (see FIG. 1(e)). Here, the measurement of the pattern size (CD) of the semi-transmissive film pattern 2a is performed as needed. Since the edge of the pattern is only a semi-transmissive film, the measurement can be performed relatively easily. Further, in the case where an additional constituent film is formed between the semi-transmissive film 2 and the resist film 3, the resist pattern 3 is used as an etching mask, and the constituent film is wet-etched (preliminary etching), and the formed film is additionally added. The film pattern is formed as an etching mask, and the semi-transmissive film pattern 2a is formed by wet etching the semi-transmissive film 2 (first etching). In this case, it is preferable to remove the additional constituent film pattern before the second patterning step below. Next, the entire surface of the transparent substrate 1 on which the semi-transmissive film pattern 2a is formed is formed on the main surface, and the light-shielding film 5 is formed (see FIG. 1(f)). Here, as in the case of forming the above-described semi-transmissive film 2, a conventional film forming apparatus can be used. The material of the light-shielding film 5 can be selected from the same as those exemplified as the material of the semi-transmissive film 2. Or it may be a monomer of the above-mentioned metal such as Cr or Si. Further, a reflection reducing layer that reduces (suppresses) the reflection of light may be provided on the surface portion of the light shielding film. Further, as described above, in the present embodiment, the light shielding film 5 is selected to have a specific etching difference with respect to the material used for the semi-transmissive film 2. For example, the etching rate ratio between the etching liquid of the light shielding film 5 and the semi-transmissive film 2 and the semi-transmissive film 2 is 1/50 or less, preferably 1/100 or less. Therefore, for example, a material containing Si may be used for the semi-transmissive film 2, and a material containing Cr may be used for the light-shielding film 5, or the like. Further, the film thickness of the light-shielding film 5 is set in consideration of the fact that the light-shielding property can be sufficiently exhibited and the etching which will be described later does not require much time. Specifically, the optical density OD is 3 or more, preferably 4 or more, and for example, 4 ≦ OD ≦ 6 can be used. Next, a resist film 6 is formed on the light-shielding film 5 (here, a positive type is also used), and a pattern specific to 7 (second drawing) is drawn (see FIG. 1(g)). The drawing method is the same as the case of the first drawing described above. However, the transmittance distribution data measured in the in-plane obtained after the film formation of the semi-transmissive film 2 is unacceptable to the extent that it is to be corrected by the pattern of the light-shielding film 5, and can be processed. 2 Depicting the data used for depiction. For example, in the fine semi-transmissive portion adjacent to the light-shielding portion, the transmission intensity of the exposure light transmitted through the semi-transmissive portion tends to decrease. With this principle, for example, a semi-transmissive portion having a lower transmittance than a design value can be corrected in a direction to increase the light transmission intensity of the exposure light by making the size larger than the design value. Next, the resist film 6 thus drawn is developed to form a resist pattern 6a (second resist pattern) (see FIG. 1(h)). Next, the formed resist pattern 6a is used as an etching mask, and the light shielding film 5 is formed by wet etching (second etching) to form the light shielding film pattern 5a (see FIG. 1(i)). Since the etching target is only the light shielding film 5, the etching end point can be easily set, for example, by referring to the etching rate which is grasped in advance. Further, as described above, in the present embodiment, since the semi-transmissive film 2 is made of a material resistant to the etchant of the light-shielding film 5, the second etching process is performed on the semi-transmissive portion forming region. Only the light-shielding film 5 is removed by etching, and the semi-transmissive film pattern 2a of the lower layer is substantially free from etching. Then, the remaining resist pattern 6a is removed and removed, and the photomask 20 (multi-step mask) including the transfer pattern of the light transmitting portion, the light blocking portion, and the semi-light transmitting portion is completed (see FIG. 1(j)). Further, the photomask 20 (multi-step mask) exemplified herein has the following constitution. In other words, the light transmitting portion is formed by exposing the surface of the transparent substrate, and the semi-transmissive portion (first transmission control portion) has a portion in which only the semi-transmissive film (the first thin film) is formed on the transparent substrate, and the light shielding portion (second The transmission control unit) has a portion on which only the light shielding film (the second film) is formed on the transparent substrate. Further, the photomask 20 has an adjacent portion of the light shielding portion and the translucent portion. In the light-shielding portion, a laminated portion of the semi-transmissive film (semi-transmissive film pattern 2a) and the light-shielding film (light-shielding film pattern 5a) is provided at a certain width in the vicinity of the edge of the semi-transmissive portion. This is a case in which the alignment shift occurs in the above-described two-time drawing (the first drawing and the second drawing), whereby the light shielding portion and the semi-light transmitting portion are not adjacent to each other, and are used for absorption. The alignment margin of the alignment offset. The alignment margin can be formed by processing the drawing data of the first drawing or the second drawing. For example, in the vicinity of the boundary between the light-shielding portion and the semi-transmissive portion, the edge portion of the second resist pattern and the edge portion of the semi-transmissive film pattern that has been formed may be preliminarily set to have a second anti-resistance The size of the etched pattern. In this case, as the processing of the drawing data, the width M (see FIG. 1(j)) of the laminated portion is not particularly limited, but may be, for example, 0.5 μm or more, preferably 0.5 to 2 μm, and more preferably 0.5 to 1 μm. . In other words, in the photomask of the above-described manufacturing method, the semi-transmissive portion forms only a semi-transmissive film on the transparent substrate, and the light-shielding portion forms only a light-shielding film on the transparent substrate. Moreover, the present invention also provides a photomask. The photomask 20 obtained by the present embodiment has the following features. In other words, a photomask is provided with a photomask including a light transmitting portion, a light blocking portion, and a transfer pattern of a semi-transmissive portion on a transparent substrate, and the transparent portion is exposed on the surface of the transparent substrate. The semi-transmissive portion is formed by forming the semi-transmissive film on the transparent substrate without forming the light-shielding film, and the light-shielding portion is formed by forming at least the light-shielding film on the transparent substrate, and the half The etched cross section of the light-shielding film is formed on the boundary between the light-transmitting portion and the light-shielding portion without forming the etched cross section of the semi-transmissive film. That is, as is clear from Fig. 1(j), the edges of the semi-transmissive film pattern 2a and the light-shielding film pattern 5a have a wet-etched cross section of the semi-transmissive film and the light-shielding film, respectively, but the edge of the semi-transmissive film pattern 2a The position does not coincide with the edge position of the light shielding film pattern 5a. Here, the etched cross section is a section which is wet etched in the present embodiment. Thus, the position of the etched cross section of the semi-transmissive film and the light-shielding film is inconsistent with the above-described alignment margin. As described above, in the photomask of the present embodiment, the semi-transmissive film contains a material resistant to the etchant of the light-shielding film. Further, the edge portion of the light-shielding portion adjacent to the semi-transmissive portion has a laminated portion of the semi-transmissive film and the light-shielding film, and the width M of the laminated portion (see FIG. 1(j)) is preferably 0.5 to 2, for example. The range of μm. Further, in the photomask of the present embodiment, the transfer pattern is, for example, a pattern for manufacturing a display device, and is particularly useful for the manufacture of a display device. As described above, according to the present embodiment, in the etching step of each of the semi-transmissive film and the light-shielding film, only the respective films are etched. Therefore, the pattern size (CD) variation due to the side etching can be reduced as compared with the case where the laminated plurality of sheets are continuously etched, since the etching time is set to be short. In particular, if a single film is etched in all the etching steps, the time required for etching can be calculated by using the film quality and the film thickness in advance, so that the dimensional deviation caused by the side etching can be minimized. Further, according to the configuration of the photomask of the present embodiment, since the transmittance management of the semi-transmissive film is simpler and more accurate, it is of great significance for realizing the manufacture of a high-definition and energy-saving high-definition display device. That is, according to the present embodiment, it is possible to provide a method of manufacturing a photomask capable of producing a multi-step mask having a finer, higher CD precision and higher transmittance accuracy, and a photomask. In the above-described embodiment, the first transmission control unit is a semi-transmissive portion that transmits a part of the exposure light, and the second transmission control unit is a light-shielding portion, and the semi-transparent film is exemplified as the first film. Although the light shielding film is exemplified as the second film, the production method of the present invention is not limited thereto, and an excellent effect can be obtained in the case of using another film. For example, the first film and the second film may be semi-transmissive films each having a specific exposure light transmittance. In this case, the first film and the second film may each be a film containing Si, Cr, Ta, Zr or the like exemplified as the semi-transmissive film material, or may be oxides, nitrides, or carbides thereof. Wait for the appropriate person. In the case where the first film and the second film are semi-transmissive films each having a specific exposure light transmittance, they have resistance to each other between the two films. For example, one of the Cr films is used, and the other is made of a Cr system. Si-based or transition metal telluride systems are employed. Further, in the photomask of the present invention, as the method of using the first film and the second film, for example, more specifically, the above-mentioned transparent substrate has a portion in which only the portion of the first film is formed. The exposure light of the first transmission control unit has a phase difference with respect to the representative wavelength of the exposure light of the light transmitting portion exposed through the surface of the transparent substrate Satisfy In the case of ≦90, b. the phase difference of the representative wavelength of the exposure light transmitted through the light transmitting portion by the exposure light of the first transmission control unit Satisfy ≦90, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, c. the phase difference of the exposure light transmitted through the first transmission control unit with respect to the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 150≦ In the case of ≦210, d. the phase difference of the exposure light transmitted through the first transmission control unit with respect to the representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, e. the exposure light of the second transmission control unit having the portion where only the second film is formed on the transparent substrate, The representative wavelength of the exposure light passing through the light transmitting portion, the phase difference (degree) meets 0< In the case of ≦90, f. the exposure light passing through the second transmission control unit, the phase difference with respect to the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦80, g. the exposure light of the second transmission control unit, and the phase difference of the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, and the like can be exemplified as a useful example. In either case, the effect of the present invention in which the CD precision can be controlled high can be obtained. Further, since the optical characteristics of the first transmission control unit and the second transmission control unit can be independently designed, it is possible to produce a high-quality photomask having a desired design value. As the multi-step mask of the photomask of the present invention, a configuration of a to g or the like can be appropriately selected, and it is suitable for use. The photomask of the present invention includes, for example, the photomask described in the first embodiment, wherein the a. or b. is used for the first film, and the light shielding film is used for the second film. Such a multi-step mask functions as a plurality of masks as described above. Thereby, the multi-step mask has the advantage of improving the manufacturing efficiency of the display device or for forming a photomask having a three-dimensional structure having a step by transfer. Further, in the photomask of the present invention, for example, in the photomask described in the first embodiment, the above-described c. or d. may be used for the first film, and in this case, the function of the phase shift mask is exhibited. A light-shielding film may be used for the second film in this case, or a semi-transmissive film described in the above e. or f. may be used. The phase shift mask has a function of increasing contrast or DOF (Depth of Focus) by interfering with light generated by a boundary between a semi-transmissive portion that reverses the phase of transmitted light and a non-reversed light-transmitting portion. In particular, when the above-mentioned c. or d. is used for the first film and the above e. or f. is used for the second film, a photomask having both the function of the multi-step mask and the function of the phase mask can be realized. In the case where the first transmission control unit and the second transmission control unit are both semi-transmissive portions, a laminated portion of the first thin film and the second thin film layer is formed in the vicinity of the boundary thereof, and the width thereof is sufficiently small. Therefore, the condition that hinders the optical effect of the mask is not substantially produced. In this case, it is preferable that the width of the laminated portion can be 1 μm or less, and further 0.75 μm or less. More preferably, it is 0.25 to 0.75 μm. Further, the width M of the laminated portion on the drawing data may be the same range. On the other hand, the size of the first transmittance control unit and the second transmittance control unit (or the light shielding unit) is preferably at least 2 μm, preferably more than 3 μm. [Second Embodiment] Fig. 2 is a view showing a procedure of a second embodiment of a method of manufacturing a photomask according to the present invention. Hereinafter, each step will be described in order. First, a mask blank 10 having a semi-transmissive film 2 having a specific exposure light transmittance is formed on the transparent substrate 1 (see FIG. 2(a)). The mask blank 10 is the same as the mask blank prepared in the first embodiment. Therefore, the range of the light transmittance Tf of the semi-transmissive film 2 can be the same as that of the first embodiment. Further, the material of the semi-transmissive film 2 may be appropriately selected from those exemplified in the first embodiment. However, in the present embodiment, since the etching stopper film is provided between the semi-transmissive film and the light-shielding film as will be described later, it is not necessary to use etching characteristics between the semi-transmissive film 2 and the light-shielding film 5 to be described later. . Therefore, for example, a Cr-based material is used for the material of the semi-transmissive film 2, and the light-shielding film 5 is also made of a Cr-based material without any hindrance. Further, after the film formation of the semi-transmissive film 2 is carried out, an appropriate number of measurement points are set in the plane as in the first embodiment, and the light transmittance is measured in advance. Since it is formed on the substrate in a single film state, it can be easily and accurately measured. Next, the resist film 3 is applied to the mask blank 10 described above, and a pattern of 4 (first drawing) is drawn (see FIG. 2(b)). If necessary, the surface of the semi-transmissive film 2 can be subjected to a surface treatment for improving the adhesion to the resist film. The coating of the resist film 3 is formed, and a known one such as a slit coater or a spin coater can be used as described above. Although any of the positive type and the negative type may be used as appropriate, in the present embodiment, an example in which a positive type is used will be described. For the formed resist film 3, a drawing device is used, and drawing is performed based on the drawing material of the desired pattern. The drawing device uses a laser as in the first embodiment. Next, the resist film 3 thus drawn is developed to form a resist pattern 3a (first resist pattern) (see FIG. 2(c)). Next, the formed resist pattern 3a is used as an etching mask, and the semi-transmissive film pattern 2a is formed by wet etching (first etching) (see FIG. 2(d)). Here, since the etching target is only the semi-transmissive film 2, the etching end point can be accurately set with reference to the etching rate which is grasped in advance. The remaining resist pattern 3a is removed by peeling off (see FIG. 2(e)). Here, the measurement of the pattern size (CD) of the semi-transmissive film pattern 2a is performed as needed. Since the edge of the pattern is only a semi-transmissive film, the measurement can be performed relatively easily. In the present embodiment, the entire surface of the transparent substrate 1 on which the semi-transmissive film pattern 2a is formed on the main surface is formed, and an etching stopper film 8 is formed (see FIG. 2(f)). The etching stopper film 8 contains a material resistant to an etchant of the light shielding film 5 to be described later. For example, the etching stopper film 8 is preferably an etching liquid with respect to the light shielding film 5, and the etching rate ratio with the light shielding film 5 is 1/50 or less, preferably 1/100 or less. Therefore, for example, in the case where a material containing Cr is used for the light-shielding film 5, a material containing Si may be used for the etching stopper film 8, or the like. The material of the etching stopper film 8 can be selected from among the materials which are semi-transmissive films or light-shielding films in the first embodiment, in consideration of such considerations. Next, on the etching stopper film 8, that is, on the main surface of the transparent substrate 1 on which the semi-transmissive film pattern 2a and the etching stopper film 8 are formed, a light shielding film 5 is further formed (refer to FIG. 2(g) ). Further, the etching stopper film 8 and the light shielding film 5 may be formed by using the same film forming apparatus as described above. Further, the material of the light-shielding film 5 may be appropriately selected from those exemplified in the first embodiment. However, as described above, in the present embodiment, between the material of the light-shielding film 5 and the semi-transmissive film 2 There is no need for mutual etching selectivity. Next, a resist film 6 is formed on the light-shielding film 5 (here, a positive type is also used), and a pattern specific to 7 (second drawing) is drawn (see FIG. 2(h)). The drawing method is the same as the case of the first drawing described above. Further, as described above, the transmittance distribution data measured in the plane obtained after the film formation of the semi-transmissive film 2 is unacceptable, and is corrected by the pattern of the light shielding film 5. The drawing data for the second drawing can be processed. Next, the resist film 6 thus drawn is developed to form a resist pattern 6a (second resist pattern) (see FIG. 2(i)). Next, the formed resist pattern 6a is used as an etching mask, and the light shielding film 5a is formed by wet etching (second etching) to form the light shielding film pattern 5a (see FIG. 2(j)). Since the etching target is only the light shielding film 5, the etching end point can be easily set by referring to the etching rate which is grasped in advance. Further, as described above, in the present embodiment, since the etching stopper film 8 includes a material resistant to the etchant of the light shielding film 5, only the light shielding film 5 is etched and removed in the second etching. Then, the remaining resist pattern 6a is removed and removed, and a photomask 30 (multi-step mask) including a transfer pattern including a light transmitting portion, a light blocking portion, and a semi-light transmitting portion is completed (see FIG. 2(k)). Further, thereafter, the etching stopper film 8 exposed on the surface of the mask 30 is removed as needed. In the case where the etching stopper film 8 is removed, an etching selectivity is employed between the semi-transmissive film 2 and the etching stopper film 8 in advance. That is, for example, both the semi-transmissive film 2 and the light-shielding film 5 are made of a Cr-containing film, and the etching-stopping film 8 is made of a Si-containing film, or the opposite. Further, in the case where the light transmittance of the semi-transmissive portion or the light-transmitting portion of the mask 30 is not particularly affected, the etching stopper film 8 may not be removed. Further, the photomask 30 (multi-step mask) exemplified in the present embodiment also has a portion adjacent to the light shielding portion and the translucent portion. In the light-shielding portion, a laminated portion of the semi-transmissive film (semi-transmissive film pattern 2a) and the light-shielding film (light-shielding film pattern 5a) is provided at a certain width in the vicinity of the edge of the semi-transmissive portion. It is considered that the alignment shift occurs in the above-described two-time drawing (the first drawing and the second drawing), and the light shielding portion and the semi-light transmitting portion are not adjacent to each other, and are used to absorb the Align the offset alignment margin. The alignment margin can be formed by processing the drawing data of the first drawing or the second drawing. For example, the width M (see FIG. 2(k)) of the laminated portion is not particularly limited, but may be, for example, 0.5 to 2 μm, or preferably 0.5 to 1 μm. This is also the same as in the first embodiment. Further, the photomask 30 obtained by the present embodiment has the following features as in the first embodiment. In other words, a photomask is provided with a photomask including a light-transmitting portion, a light-shielding portion, and a transfer pattern of a semi-transmissive portion on a transparent substrate, and the light-transmitting portion is formed by exposing the surface of the transparent substrate. The semi-transmissive portion is formed by forming the semi-transmissive film on the transparent substrate without forming the light-shielding film, and the light-shielding portion is formed by forming at least the light-shielding film on the transparent substrate, and the semi-transparent portion The etched cross section of the light-shielding film is formed on the boundary between the light portion and the light-shielding portion without forming the etched cross section of the semi-transmissive film. The material of the semi-transmissive film or the light-shielding film of the photomask is as described above, and in the photomask of the embodiment, the etching selectivity is not required between the semi-transparent film and the light-shielding film. Further, as described above, the edge portion of the light-shielding portion adjacent to the semi-transmissive portion has the laminated portion of the semi-transmissive film and the light-shielding film, and the width M of the laminated portion (refer to FIG. 2(k)) A preferred range is, for example, 0.5 to 2 μm. Further, in the photomask of the present embodiment, the transfer pattern is, for example, a pattern for manufacturing a display device, and is particularly useful for the manufacture of a display device. As described above, in the present embodiment, only the respective films are etched in the respective etching steps of the semi-transmissive film and the light-shielding film. Therefore, the pattern size (CD) variation due to the side etching can be reduced as compared with the case where the laminated plurality of sheets are continuously etched, since the etching time is set to be short. In particular, if a single film is etched in all the etching steps, the time required for etching can be calculated by using the film quality and the film thickness in advance, so that the dimensional deviation caused by the side etching can be minimized. Further, according to the configuration of the photomask of the present embodiment, the transmittance management of the semi-transmissive film is simpler and more accurate, and therefore, it is of great significance for realizing the manufacture of a high-definition and energy-saving high-definition display device. That is, according to the present embodiment, it is possible to provide a method of manufacturing a photomask capable of producing a multi-step mask having a finer, higher CD precision and higher transmittance accuracy, and a photomask. In the above-described embodiment, the first transmission control unit is a semi-transmissive portion through which part of the exposure light is transmitted, and the second transmission control unit is used as a light-shielding portion, and the first film is exemplified as a semi-transmission. Although the film is described as a second film as a light-shielding film, the production method of the present invention is not limited thereto, and an excellent effect can be obtained in the case of using another film. For example, the first film and the second film may be semi-transmissive films each having a specific exposure light transmittance. Further, in the photomask of the present embodiment, as a method of using the first film and the second film, for example, more specifically, a portion which is formed on the transparent substrate and which only forms the first film is formed. The exposure light of the first transmission control unit has a phase difference with respect to the representative wavelength of the exposure light of the light transmitting portion exposed through the surface of the transparent substrate Satisfy In the case of ≦90, b. the phase difference of the representative wavelength of the exposure light transmitted through the light transmitting portion by the exposure light of the first transmission control unit Satisfy ≦90, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, c. the phase difference of the exposure light transmitted through the first transmission control unit with respect to the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 150≦ In the case of ≦210, d. the phase difference of the exposure light transmitted through the first transmission control unit with respect to the representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, e. the exposure light of the second transmission control unit having the portion where only the second film is formed on the transparent substrate, The representative wavelength of the exposure light passing through the light transmitting portion, the phase difference (degree) meets 0< In the case of ≦90, f. the exposure light passing through the second transmission control unit, the phase difference with respect to the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦80, g. the exposure light of the second transmission control unit, and the phase difference of the representative wavelength of the exposure light transmitted through the light transmitting portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies the case of 5≦Tf≦60, and the like can be exemplified as a useful example. In either case, the effect of the present invention in which the CD precision can be controlled high can be obtained. Further, since the optical characteristics of the first transmission control unit and the second transmission control unit can be independently designed, it is possible to produce a high-quality photomask having a desired design value. Further, in the photomask of the present invention according to the second embodiment, as in the first embodiment, a configuration such as a to g can be appropriately selected, and it can be suitably used. The first embodiment and the second embodiment of the present invention have been described above. Further, in the above embodiment, the other constituent film may be present on any of the semi-transmissive film 2, the light shielding film 5, and the etching stopper film 8 within a range that does not inhibit the effects of the present invention. Down, or in the middle. Moreover, the present invention provides a method of manufacturing a display device, comprising the steps of, for example, preparing the photomask of the above-described embodiment, using an exposure device, and transferring the transfer pattern to the transfer target. According to the present invention, by manufacturing the display device using the photomask, it is possible to manufacture a high-definition display device which realizes high definition and energy saving. That is, the use of the photomask of the present invention is not limited. For example, it can be used as a panel substrate for manufacturing a display device (for example, a liquid crystal display or an organic EL display), or as a transfer pattern for use in various layers. For example, a person who has a transfer pattern for manufacturing a TFT (Thin Film Transistor) is exemplified. In a bottom gate type TFT using amorphous Si or an oxide semiconductor, it is advantageous as a mask for performing a step of forming a semiconductor layer and a source/drain layer with one exposure. Use. Further, the photomask of the present invention is also advantageously used in the case of producing a spacer for liquid crystal by a photosensitive insulating layer. The step of forming the step structure on the photosensitive insulating film by one exposure can be performed, and the spacer which forms the cell gap by one exposure and the height for preventing the damage when the pressing is applied can be efficiently performed. Slightly lower spacers, etc. As the exposure apparatus used for the photomask of the present invention, for example, a projection exposure method in which the numerical aperture (NA) of the optical system is 0.08 to 0.15 and the coherence factor (σ) is equal to or less than 0.5 to 0.9 can be used. Alternatively, a proximity exposure method can also be used. It is of course also possible to use an exposure device that reduces exposure or magnifies exposure.

1‧‧‧Transparent substrate
2‧‧‧ Semi-transparent film
2a‧‧‧ Semi-transparent film pattern
3‧‧‧Resist film
3a‧‧‧resist pattern
4‧‧‧ depicting
5‧‧‧Shade film
5a‧‧‧Shade film pattern
6‧‧‧Resist film
6a‧‧‧resist pattern
7‧‧‧ depicting
8‧‧‧etching stop film
10‧‧‧Photomask blank (substrate with semi-transparent film)
20‧‧‧Photomask
30‧‧‧Photomask
100‧‧‧Photomask blank
101‧‧‧Transparent substrate
102‧‧‧Shade film
102a‧‧‧Shade film pattern
103‧‧‧Resist film
103a‧‧‧resist pattern
104‧‧‧ Semi-transparent film
104a‧‧‧Semi-transparent film pattern
105‧‧‧Resist film
105a‧‧‧resist pattern
200‧‧‧ grayscale mask
M‧‧‧Width

Fig. 1 (a) to (j) are views showing the steps of the first embodiment of the method for producing a photomask according to the present invention. 2(a) to 2(k) are views showing the steps of the second embodiment of the method of manufacturing the photomask of the present invention. 3(a) to (i) are diagrams showing a method of manufacturing a conventional reticle disclosed in the prior literature. 4(f) to (i), (h'), (i') are reference diagrams showing the manufacturing steps of the prior photomask for explaining the problems of the prior art.

1‧‧‧Transparent substrate

2‧‧‧ Semi-transparent film

2a‧‧‧ Semi-transparent film pattern

3‧‧‧Resist film

3a‧‧‧resist pattern

4‧‧‧ depicting

5‧‧‧Shade film

5a‧‧‧Shade film pattern

6‧‧‧Resist film

6a‧‧‧resist pattern

7‧‧‧ depicting

10‧‧‧Photomask blank (substrate with semi-transparent film)

20‧‧‧Photomask

M‧‧‧Width

Claims (46)

A method of manufacturing a photomask, comprising: a method of manufacturing a photomask including a translucent portion, a first transmission control portion, and a transfer pattern for a second transmission control portion on a transparent substrate, comprising: a step of forming a mask blank of a first film having a specific exposure light transmittance on the transparent substrate; a first patterning step of forming the first film pattern by etching the first film; and second patterning a step of forming a second thin film on the transparent substrate on which the first thin film pattern is formed, and forming a second thin film pattern by etching the second thin film; and etching only the first thin film pattern in the second patterning step 2 film. The method of manufacturing a reticle according to claim 1, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion has a portion where only the first film is formed on the transparent substrate, and the second transmission The control unit has a portion where only the second thin film is formed on the transparent substrate. The method of producing a photomask according to claim 1 or 2, wherein the first film comprises a material resistant to an etchant of the second film. The method of producing a photomask according to claim 1 or 2, wherein the first thin film comprises a material etched by the etchant of the second thin film. The method of manufacturing a photomask according to claim 4, further comprising: forming an etching stopper film on the transparent substrate on which the first thin film pattern is formed after the first patterning step and before forming the second thin film The steps. The method of manufacturing a photomask according to claim 5, further comprising the step of removing the etching stop film of the light transmitting portion or the light transmitting portion and the first transmission control portion after the second patterning step. The method of producing a photomask according to claim 1 or 2, wherein the first film is a semi-transmissive film that partially transmits exposure light. The method of manufacturing a reticle according to claim 1 or 2, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90. The method of manufacturing a reticle according to claim 1 or 2, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90, and the light transmittance Tf(%) of the first transmission control unit satisfies 5≦Tf≦60. The method of manufacturing a reticle according to claim 1 or 2, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210. The method of manufacturing a reticle according to claim 1 or 2, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The method of manufacturing a photomask according to claim 1 or 2, wherein the second film is a semi-transmissive film that partially transmits the exposure light. The method of manufacturing the reticle of claim 1 or 2, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90. The method of manufacturing the reticle of claim 1 or 2, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦80. The method of manufacturing the reticle of claim 1 or 2, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The method of producing a photomask according to claim 1 or 2, wherein the second thin film is a light shielding film. The method of manufacturing a photomask according to claim 16, wherein the surface portion of the second film is provided with a reflection reducing layer that reduces reflection of light. The method of manufacturing a photomask according to claim 1 or 2, wherein the photomask blank has an additional constituent film and a resist film on the first film. The method of producing a photomask according to claim 18, wherein the adhesion between the additional constituent film and the resist film is higher than the adhesion between the first film and the resist film. The method of manufacturing a photomask according to claim 19, wherein before the first patterning step, a pre-patterning step of etching the additional constituent film to form an additional constituent film pattern is formed, and in the first patterning step, The first constituent film pattern is additionally used as a mask to etch the first film. The method of manufacturing a photomask according to claim 20, wherein the additional constituent film pattern is removed after the first patterning step and before the second patterning step. A method of manufacturing a reticle, comprising: a light transmitting portion, a first transmission control portion, and a second transmission control portion on the transparent substrate, wherein the first transmission control portion is adjacent to the second transmission control portion A method of manufacturing a mask for a transfer pattern of an adjacent portion, comprising: a step of preparing a mask blank having a first film having a specific exposure light transmittance on the transparent substrate; and a first patterning step; Forming a first resist pattern in a region of the first transmission control portion, forming a first thin film pattern by etching the first thin film, and forming a film on the transparent substrate on which the first thin film pattern is formed Forming a second film; and forming a second resist pattern in the region of the second transmission control portion, and forming the second film pattern by etching the second film; and in the second In the patterning step, a laminate portion of the second resist pattern and the first thin film pattern layer is formed in the adjacent portion, and only the second film is etched using the second resist pattern. The method of manufacturing a reticle according to claim 22, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion includes a portion where only the first film is formed on the transparent substrate, and the second transmission The control unit includes a portion where only the second thin film is formed on the transparent substrate. The method of manufacturing a photomask according to claim 22 or 23, wherein the width M1 of the laminated portion is in the range of 0.5 to 2 μm. A photomask comprising a photomask including a light transmission portion, a first transmission control portion, and a transfer pattern for a second transmission control portion on a transparent substrate, wherein the transfer pattern includes a specific exposure The light-transmitting first film and the second film are formed by exposing the transparent substrate to the surface of the transparent substrate, and the first transmission control unit forms the first film on the transparent substrate without forming the second film. The second transmission control unit is formed by forming at least the second thin film on the transparent substrate, and the etched section of the first thin film is not formed at the boundary between the first transmission control unit and the second transmission control unit. The etched cross section of the second film is formed. The photomask of claim 25, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, wherein the first transmission control portion has a portion on which the first thin film is formed on the transparent substrate, and the second transmission control portion is The transparent substrate has a portion where only the second thin film is formed. The photomask of claim 25 or 26, wherein the first film comprises a material resistant to the etchant of the second film. The photomask of claim 25 or 26, wherein the first film comprises a material etched by the etchant of the second film, and the second transmission control unit has an etching stop film and the second film This sequence is part of the buildup. The reticle of claim 25 or 26, wherein the edge portion of the second transmission control portion adjacent to the first transmission control portion has a laminated portion of the first film and the second film. The reticle of claim 29, wherein the width M2 of the laminated portion is in the range of 0.5 to 2 μm. The photomask according to any one of claims 25 or 26, wherein the first film is a semi-transmissive film, and the second film is a light-shielding film. A photomask comprising a photomask including a light transmission portion, a first transmission control portion, and a transfer pattern of a second transmission control portion on a transparent substrate, wherein the transfer pattern includes a specific one a first thin film pattern composed of a first thin film and a second thin film pattern composed of a second thin film, wherein the light transmitting portion is formed by exposing a surface of the transparent substrate, and the first transmission control portion is on the transparent substrate The second transmission control unit has a portion in which only the second thin film pattern is formed on the transparent substrate, and has a portion that is sandwiched between the first transmission control unit and the second transmission control unit. The laminated portion of the first thin film pattern and the second thin film pattern layer. The reticle of claim 32, wherein the width M2 of the laminated portion is in the range of 0.5 to 2 μm. The mask of claim 32 or 33, wherein the edges of the first film pattern and the second film pattern each have a wet-etched cross section of the first film and the second film. The photomask of claim 32 or 33, wherein the first film is a semi-transmissive film that partially transmits exposure light. The mask of claim 32 or 33, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90. The mask of claim 32 or 33, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion Satisfy ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The mask of claim 32 or 33, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210. The mask of claim 32 or 33, wherein the exposure light transmitted through the first transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150≦ ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The photomask of claim 32 or 33, wherein the second film is a light shielding film. The photomask of claim 32 or 33, wherein the second film is a semi-transmissive film that partially transmits exposure light. The photomask of claim 32 or 33, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90. The photomask according to any one of claims 32 to 33, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 0< ≦90, and the light transmittance Tf(%) satisfies 5≦Tf≦80. The photomask according to any one of claims 32 to 33, wherein the exposure light transmitted through the second transmission control unit has a phase difference with respect to a representative wavelength of the exposure light transmitted through the light transmission portion (degree) meets 150< ≦210, and the light transmittance Tf(%) satisfies 5≦Tf≦60. The photomask according to any one of claims 25, 26, 32 or 33, wherein the transfer pattern is a pattern for manufacturing a display device. A method of manufacturing a display device, comprising: preparing a photomask according to any one of claims 25, 26, 32 or 33; and transferring the transfer pattern to a transfer using an exposure device The steps of the body.