JP2011215197A - Photomask and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photomask and a method for manufacturing the photomask capable of suppressing reading failure of a mark pattern when a fine pattern figure is formed on a process object by using a transfer pattern composed of a semi-transmitting part and a light-transmitting part.SOLUTION: The photomask is used for transferring a pattern in a transfer pattern part onto a resist film formed on a process object to be etched, so as to form a resist pattern in the resist film functioning as a mask in the etching process, wherein the transfer pattern part comprises a light-transmitting part and a semi-transmitting part formed by patterning a semi-transmitting film formed on a transparent substrate, and a mark pattern forming part composed of a light-shielding film is provided in an area different from the area of the transfer pattern part of the transparent substrate.

Description

  The present invention relates to a photomask used in a photolithography process and a method for manufacturing the photomask.

  Currently, there are a VA (Vertical Alignment) method and an IPS (In Plane Switching) method as a method employed in a liquid crystal display device. By applying these methods, it is said that the liquid crystal reacts quickly and an excellent moving image giving a sufficient viewing angle can be provided. Also, the response speed and viewing angle are improved by using a line-and-space pattern (line-and-space pattern) with a transparent conductive film in the pixel electrode portion of the liquid crystal display device to which these methods are applied. Can be achieved.

  In recent years, in order to further improve the response speed and viewing angle of the liquid crystal, the line width of the conductive film and the line width (CD (Critical Dimension), etc.) of the conductive film are becoming finer (for example, Patent Document 1). reference).

  In general, a photolithography process is used for pattern formation of a pixel portion or the like of a liquid crystal display device. In the photolithography process, a predetermined pattern is transferred using a photomask to a resist film formed on a workpiece to be etched, and the resist film is developed to form a resist pattern. The workpiece is etched using the pattern as a mask. For example, a so-called binary mask is used as a photomask in which pixel electrodes are formed in a comb shape (a line and space pattern is formed in a transparent conductive film). The binary mask is a two-tone photomask composed of a light shielding portion (black) that blocks light by patterning a light shielding film formed on a transparent substrate and a light transmitting portion (white) that transmits light. . For example, when a line and space pattern is formed using a binary mask and a positive photoresist, a line pattern formed on a transparent substrate is formed with a light shielding portion, and the space pattern is formed with a light transmitting portion. Can be formed.

JP 2007-206346 A

  However, when the pattern shape (for example, the line width of the line-and-space pattern) is reduced, the intensity of transmitted light applied to the resist film formed on the workpiece through the light-transmitting portion of the photomask is increased. As a result, the contrast is lowered and a sufficient resolution cannot be obtained. As a result, there arises a problem that it becomes difficult to etch the workpiece. For example, if the pitch width (line + space) of the line-and-space pattern is smaller than 7 μm, the etching process conditions of the workpiece become strict and patterning becomes difficult.

  As a method of increasing the resolution and performing finer patterning, it is conceivable to apply an exposure apparatus with an increased numerical aperture, short wavelength exposure, and a phase shift mask, which have been conventionally developed as LSI manufacturing techniques. However, when these technologies are applied, enormous investment and technological development are required, and it becomes impossible to achieve consistency with the price of the liquid crystal display device provided on the market. Further, unlike LSI manufacturing, the size of the workpiece is large (for example, a square having a side of 1000 mm or more), so it is advantageous to apply wet etching instead of dry etching applied in LSI manufacturing. Therefore, in the manufacture of a liquid crystal display device, for example, it is desired that a finer pattern can be transferred while applying wet etching under the condition that the exposure light uses a wavelength in the range of i-line to g-line. .

  Further, it is conceivable to secure a necessary exposure amount by increasing the exposure amount in the photolithography process against the above-described contrast reduction during transfer. However, in order to increase the exposure amount, it is necessary to increase the output of the light source of the exposure machine or increase the exposure time, resulting in additional investment such as remodeling of the apparatus and a decrease in production efficiency. Therefore, there is a demand for a method of performing fine patterning with little additional investment and without adversely affecting production efficiency.

  In order to solve this problem, the present inventor has made the transfer pattern a translucent part and a semi-transparent part (a line pattern of a line-and-space pattern is a semi-transparent part and a space pattern is a translucent part). The method of forming in was proposed.

  By the way, when forming a translucent film on a transparent substrate and then patterning the translucent film to form a translucent part and a translucent part, a mark pattern for mask handling ( (Hereinafter referred to as a mark pattern) is also formed by patterning the semi-translucent film. That is, since the transfer pattern is formed of a semi-transparent film having a predetermined transmittance, the mark pattern formed simultaneously with the pattern formation is the same.

  As a mark pattern, an alignment mark used when a mask user sets the exposure apparatus (in order to manufacture an image device such as a liquid crystal display device by forming a pattern on the same workpiece using a plurality of masks) In addition, the positioning accuracy is very important), and there are barcodes for identifying mask products, which play an important role in photomask recognition and management. These handling mark patterns are not transfer patterns, and are therefore provided outside the transfer area during exposure (mostly around the periphery of the mask). And when reading this, reflected light or transmitted light is used by the light source and detector of the reading device. However, the specifications of many of these apparatuses are determined based on the most widely used binary mask, and the transmission of the photomask transmission area (Qz) and the light shielding part (mostly a light shielding film mainly composed of Cr). Reading is performed based on the contrast of reflectance or reflectance.

  For this reason, when the present inventor further researched, it is necessary to pay attention to the reading conditions in a photomask having a mark pattern for patterning a semi-translucent film, in other words, an existing apparatus such as an exposure machine. It was found that a reading error may occur depending on the reading conditions by.

  The present invention has been made in view of the above points. When a fine pattern shape is formed on a workpiece using a transfer pattern formed by a semi-translucent portion and a translucent portion, an alignment mark or bar is formed. Another object is to provide a photomask that can suppress a reading error of a mark pattern such as a code and a manufacturing method thereof.

  The photomask of the present invention is a photomask for manufacturing a liquid crystal display device having a transfer pattern for transferring to a resist film formed on a workpiece to be etched, and is provided in a transfer region of the photomask. Has a transfer pattern including a line-and-space pattern composed of a light-transmitting part and a semi-light-transmitting part obtained by patterning a semi-transparent film formed on a transparent substrate, and transfers a photomask A mark pattern obtained by patterning a light shielding film formed on a transparent substrate is provided outside the region.

  In the photomask of the present invention, the transfer pattern is preferably for forming a transparent electrode by wet etching.

  In the photomask of the present invention, the photomask forms a line-and-space pattern having the same line width LP and space width SP on the workpiece by etching, and the transfer pattern of the photomask is: The line width LM preferably includes a line and space pattern larger than the space width SM.

  In the photomask of the present invention, the line-and-space pattern preferably has a pitch that is the sum of the line widths of the lines and spaces of 2 μm to less than 7 μm.

  In the photomask of the present invention, it is preferable that the mark pattern has a light transmitting portion where the transparent substrate is exposed and a light shielding portion where the light shielding film is exposed.

  In the photomask of the present invention, when the transmittance of the translucent part is 100%, the transmissivity of the semi-translucent part is preferably 1% or more and 30% or less.

  The method for producing a photomask of the present invention is a method for producing a photomask having a transfer pattern including a line and space pattern in a transfer region and having a mark pattern outside the transfer region, wherein the light shielding film is formed on a transparent substrate. A transparent substrate in a state in which a light shielding film is patterned to remove the light shielding film in the transfer region and a mark pattern is formed outside the transfer region, and a mask is provided on the mark pattern. The method includes: a step of forming a semi-transparent film thereon; and a step of patterning the semi-transparent film to form the transfer pattern formed by the translucent portion and the semi-transparent portion.

  The method for producing a photomask of the present invention is a method for producing a photomask having a transfer pattern including a line-and-space pattern in a transfer region and having a mark pattern outside the transfer region. A step of forming a light film, a step of forming a light-shielding film on the semi-transparent film, and drawing and developing a transfer pattern and a mark pattern on the resist film formed on the light-shielding film, and developing the first film Forming a resist pattern, patterning the light-shielding film and the semi-transparent film using the first resist pattern, and removing the first resist pattern; Then, forming a second resist pattern so that the laminated pattern of the light shielding film and the semi-transparent film located in the transfer region is exposed, and using the second resist pattern, A step of forming a transfer pattern formed from the light-transmitting portion and the semi-light-transmitting portion and a mark pattern formed from the light-transmitting portion and the exposed light-blocking film pattern by removing the light-blocking film formed on the light film. It is characterized by having.

  The photomask manufacturing method of the present invention is a photomask manufacturing method having a transfer pattern including a line-and-space pattern in a transfer region and having a mark pattern outside the transfer region, the transfer region on a transparent substrate A step of forming a semi-transparent film with a mask provided outside, a step of forming a light-shielding film on the semi-transparent film and an exposed transparent substrate, and a resist film formed on the light-shielding film In addition, a first resist pattern is formed by drawing and developing a transfer pattern and a mark pattern, and a light shielding film and a semi-transparent film are patterned using the first resist pattern, whereby a light shielding film is formed in the transfer region. Forming a light-shielding film pattern outside the transfer region, and removing the first resist pattern, and then exposing the layer pattern of the transfer region. Forming a second resist pattern on the surface, and removing the light-shielding film formed on the semi-transparent film using the second resist pattern, thereby transferring the translucent part and the semi-transparent part. A pattern, and a step of forming a mark pattern formed of a light transmitting portion and a light shielding film pattern.

  The pattern transfer method of the present invention uses the above-described photomask, exposes the resist film on the workpiece with an exposure machine having an exposure light source in the range of i-line to g-line, and uses the obtained resist pattern. By performing wet etching, a pattern having the same line and space width is processed.

  According to one embodiment of the present invention, a transfer pattern portion of a photomask is formed by a semi-transparent portion and a translucent portion, and a portion for forming a mark pattern such as an alignment mark or a barcode is provided by a light-shielding film. In addition to forming a fine pattern shape on the workpiece, reading errors of mark patterns such as alignment marks and barcodes can be suppressed, and manufacturing efficiency can be improved.

It is a figure which shows an example of a structure of a photomask. It is a figure which shows an example of the manufacturing method of a photomask. It is a figure which shows an example of the manufacturing method of a photomask. It is a figure which shows an example of the manufacturing method of a photomask. It is a figure explaining the photolithographic process using a photomask and this photomask. It is a figure which shows the transmittance | permeability of the photomask at the time of providing a line pattern in the light-shielding part. It is a figure which shows the transmittance | permeability of the photomask at the time of providing a line pattern in a semi-translucent part. It is a figure which shows the transmittance | permeability of the photomask at the time of providing a line pattern in a semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the light-shielding part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the light-shielding part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part. It is a figure which shows the cross-sectional shape after image development of the resist film exposed using the photomask which provided the line pattern in the semi-translucent part.

  As described above, the present inventors diligently studied a photomask capable of suppressing the resolution degradation of the transfer pattern formed on the photomask and enabling precise transfer with the miniaturization of the pattern. A photomask having a transfer pattern formed by a translucent part and a semi-transparent part (a line pattern of a line and space pattern is a semi-transparent part and a space pattern is a translucent part) has already been proposed. .

  As described above, after a semi-transparent film is formed on a transparent substrate, the semi-transparent film is patterned to form a transfer pattern having a translucent part and a semi-translucent part in the transfer region of the photomask. In this case, the mark pattern formed outside the transfer region is formed on a film (semi-transmissive film) different from the conventional one.

  Here, the transfer region is a region including a transfer pattern to be transferred to the resist on the workpiece, and is a region irradiated with exposure light. For example, in FIG. 1A, it can be a region of the transfer pattern portion 102.

  As a result of further research by the inventor, when a mark pattern is formed on a semi-transparent film on a transparent substrate, the surface of the semi-transparent film is dependent on conditions such as transmittance and reflectance of the semi-transparent film. It has been found that there is a possibility that a mark pattern reading error may occur in the exposure machine due to the interference of the above. Therefore, as a result of intensive studies by the present inventors, a mark pattern forming portion for forming alignment marks and barcodes is separately used in a mask in which a transfer pattern is formed by a light transmitting portion and a semi-light transmitting portion. It was found that reading errors of alignment marks and barcodes can be suppressed by forming the above.

  Here, the light-shielding film preferably uses exposure light (i-line to g-line) having an optical density (OD) of 3 or more, and shields the resist so that the resist on the workpiece is not substantially exposed. .

  Hereinafter, an example of the photomask of the present invention will be described with reference to FIG. Note that in FIG. 1, FIG. 1A shows a top surface of a photomask, and FIGS. 1B to 1D show cross sections in FIG.

<Photomask>
The photomask 100 has a transfer pattern portion 102 formed on a transparent substrate 101 and a mark pattern formation portion 103. The transfer pattern portion 102 is formed of a semi-transparent portion 102a and a translucent portion 102b, and can be obtained by forming a semi-transparent film on the transparent substrate 101 and then patterning the semi-transparent film. The mark pattern forming unit 103 is formed of a light shielding film, and a mark pattern such as an alignment mark or a barcode is formed on the surface of the light shielding film.

  The mark pattern forming unit 103 may be provided at least in a region where a mark pattern such as the alignment mark 105 or the barcode 106 is formed. In general, since the mark pattern is formed on the end side on the surface of the transparent substrate 101, it is preferable to provide the mark pattern forming portion 103 in the peripheral portion outside the region of the transfer pattern portion 102. In this case, the pattern of the light shielding film may be provided in an annular shape along the peripheral area on the surface of the transparent substrate 101 (see FIG. 1), or a light shielding film may be selectively provided in the area where the mark pattern is formed. Also good.

  The mark pattern is most preferably composed of a light-transmitting portion where the transparent substrate is exposed and a light-shielding portion where the light-shielding film is exposed. In the case of a light-shielding portion in which a semi-transparent film is laminated on a light-shielding film, there is a possibility that the mark pattern reading by reflected light becomes unstable. In addition, when the mark pattern is formed by a light-shielding portion where the light-shielding film is exposed and a semi-light-transmitting portion in which a semi-transparent film is formed on a transparent substrate, reading accuracy is insufficient when reading with transmitted light. there is a possibility.

  The transfer pattern part 102 can be formed of a translucent part and a semi-transparent part formed by patterning a semi-transparent film formed on the transparent substrate 101. When the transfer pattern portion 102 is formed with a line-and-space pattern, the line pattern 102a may be formed with a semi-transparent portion and the space pattern may be formed with a translucent portion 102b.

  As described above, even in a photomask in which the transfer pattern portion is formed of a semi-transparent portion and a translucent portion, the mark pattern reading defect can be suppressed by providing the portion where the mark pattern is formed with the light shielding film. it can. By using such a photomask, it is possible to improve the productivity of the manufacturing process by forming a fine pattern shape on the workpiece and suppressing errors in reading the mark pattern.

  Hereinafter, an example of a photomask and a pattern transfer method using the photomask will be described with reference to FIGS. In FIG. 5, a predetermined transfer pattern including a line-and-space pattern formed on the photomask 500 is transferred to a resist film 504 formed on a workpiece 503 to be etched. In this example, the resist pattern 505 after development is used as a mask in etching.

  The photomask 500 has a predetermined transfer pattern including a line and space pattern, and the predetermined transfer pattern including the line and space pattern is formed on a resist film 504 formed on the workpiece 503. Transcript. The transfer pattern of the photomask 500 can be formed by a translucent part and a semi-transparent part formed by patterning a semi-transparent film formed on the transparent substrate 510. In addition, the line pattern of the line and space pattern of the photomask 500 is provided in the semi-translucent portion 501, and the space pattern is provided in the translucent portion 502.

  When the line and space pattern of a photomask is formed with a light-shielding part and a light-transmitting part as in the past, the pitch width of the line and space pattern is small (near the resolution limit of the exposure tool). ), The intensity of transmitted light irradiated to the resist film through the light-transmitting part decreases, and the contrast of the transmitted light corresponding to the light-shielding part and the light-transmitting part decreases. As a result, the exposed resist film remains. As a result, there arises a problem that the workpiece cannot be patterned. To solve this problem, reduce the resolution limit of the exposure machine (increase the resolution), increase the amount of applied exposure, shorten the wavelength of the exposure light, or apply a phase shift mask to reduce the transmitted light. It may be necessary to increase the strength.

  On the other hand, as shown in FIG. 5, the pitch width of the line and space pattern of the photomask 500 is reduced by forming the line pattern of the photomask 500 with the semi-translucent portion 501 instead of the light shielding portion. Even in such a case, the resist film 504 is prevented from decreasing the intensity of transmitted light irradiated to the resist film 504 through the light transmitting portion 501 (space pattern), and is exposed through the light transmitting portion 502 after development. 504 can be removed. This is because forming the line pattern by the semi-translucent portion 501 provides the same effect as increasing the exposure amount in the photolithography process. This makes it possible to form a desired fine pattern with an exposure amount that can be applied in a conventional photolithography process (without changing the exposure amount or with a smaller exposure amount).

  In addition, the pitch width of the line and space pattern of the photomask 500 is preferably 2.0 μm or more and less than 7.0 μm. A fine pattern with a pitch width of less than 7.0 μm has a dense electric field when it is used as a liquid crystal device, and is excellent in terms of response speed and brightness of the liquid crystal. There is inconvenience that there is not. On the other hand, according to the method of the present invention, a particularly remarkable effect can be obtained in the fine pattern as described above which is close to the resolution limit of the exposure machine. Further, if the pitch width is 2 μm or more, a sufficient light intensity can be obtained by selecting the film transmittance of the semi-transparent film, so that a sufficient resolution improvement effect can be obtained.

  The phase difference in the semi-translucent portion 501 is not particularly limited. This is because an excellent resolution improvement effect can be obtained as a line and space pattern for manufacturing a liquid crystal display device without depending on the reversal of exposure light. In selecting a semi-transparent film, an appropriate film thickness is obtained when the phase difference from the translucent part is 30 degrees or more and 180 degrees or less with respect to the representative wavelength in the range of i-line to g-line. Therefore, it is easy to obtain an appropriate transmittance. More preferably, it is 30 degrees or more and 90 degrees or less. More preferably, the phase shift amount of the semi-transmissive film formed in the semi-transmissive portion is 30 to 90 degrees with respect to all wavelengths of i-line to g-line.

When the photomask 500 shown in FIG. 5 is used, the resist film 504 is exposed not only through the translucent portion 502 (space pattern) but also through the semi-transparent portion 501 (line pattern). The film thickness t ₁ of the resist pattern 505 is smaller than the initial film thickness value t ₀ of the resist film 504. When the thickness t ₁ of the resist pattern 505 is too small, detrimental when etching (resist pattern 505 does not function as a mask disappears), the transmittance of the semi-light-transmitting portion 501 with respect to the exposure light, Toru It is preferable to set in consideration of the intensity of transmitted light of the light portion 502 and the film thickness of the resist pattern 505. For example, when the transmittance of the light transmitting portion of the photomask 500 is 100% with respect to the exposure light, the transmittance of the semi-transparent portion 501 with respect to the exposure light is preferably 1% or more and 30% or less, more preferably 1%. It can be made 20% or less and more preferably 3% or more and 20% or less. Within this range, even if the pitch width of the line-and-space pattern of the photomask 500 is reduced, the intensity of the transmitted light of the light-transmitting portion 502 is suppressed from decreasing, and the resist pattern The film thickness t ₁ of 505 can be left in an amount necessary for etching. Note that the transmittance of the light-transmitting portion of the photomask 500 is 100% when the transmittance of a sufficiently wide light-transmitting portion (a light-transmitting portion of 20 μm square or more) in the photomask 500 is 100%.

  Next, a pattern transfer method using the above-described photomask 500 will be described.

  First, after a positive resist film 504 is formed over the workpiece 503, the resist film 504 is irradiated with exposure light through the photomask 500 (see FIG. 5A). In this case, the exposure light is irradiated to the resist film 504 through the light transmitting portion 502 and the semi-light transmitting portion 501. Next, after developing the resist film 504 to form a resist pattern 505 (FIG. 5B), the workpiece 503 is etched using the resist pattern 505 as a mask, so that at least one of the workpieces 503 is obtained. The part can be formed in a line and space pattern (see FIGS. 5C and 5D).

In the pattern transfer method described with reference to FIG. 5, since the line pattern of the photomask 500 is formed using the semi-translucent portion 501 instead of the light shielding portion, the film thickness t _{1 of} the developed resist pattern 505 is the initial value of the resist film 504. smaller than the film thickness value _{t 0.} Therefore, it is preferable to perform the etching process on the workpiece 503 using wet etching. This is because when the dry etching is used, the resist pattern 505 is also etched. Therefore, when the resist pattern 505 is thin, the resist pattern 505 serving as a mask may be lost during the etching process.

  On the other hand, in the case of using wet etching, by increasing the etching selection ratio between the workpiece 503 and the resist material used for the resist film 504, even when the resist pattern 505 has a small film thickness, The disappearance of the resist pattern 505 can be suppressed. In order to effectively suppress the disappearance of the resist pattern 505 during the etching process, the etching selectivity of the workpiece 503 to the etchant of the wet etching is 10 times (1:10) or more, preferably 50. What is necessary is just to form using the resist material used as double (1:50) or more.

Further, even when the film thickness t ₁ of the resist pattern 505 is small, the shorter the etching processing time of the workpiece 503, the more the resist pattern 505 can be prevented from disappearing during the etching processing. For example, when the thickness of the workpiece 503 is small, the etching processing time can be shortened. The film thickness of the workpiece 503 is determined in consideration of the etching conditions and the like. As an example, the etching processing time can be shortened by forming the workpiece 503 to be about 40 nm to 150 nm. Can do. As described above, the pattern transfer method described in this embodiment is particularly effective for patterning a workpiece having a small film thickness. Further, when the film thickness of the workpiece 503 is small, the transmittance of the semi-transparent portion 501 of the photomask 500 can be set high. Thereby, the exposure amount of the exposure light in a photolithography process can be reduced.

  Further, when wet etching is applied as an etching process for the workpiece 503, the workpiece 503 is isotropically etched as compared with dry etching. That is, at the time of etching, the side surface of the transferred portion 503 overlapping with the resist pattern 505 is also etched (side etching) (see FIG. 5C). Therefore, when the line width of the line and space pattern of the photomask 500 (the width of the semi-translucent portion 501) is LM and the space width (the width of the translucent portion 502) is SM, the object to be processed after the etching process. The line width LP of the line and space pattern formed in 503 is smaller than LM, and the space width SP is larger than SM.

  Therefore, when the line width LP and the space width SP of the line-and-space pattern formed on the workpiece 503 are made equal (LP≈SP), the line width LM of the photomask 500 is set to the space width SM. It is preferable to provide a larger (LM> SM). For example, bias portions 506a and 506b can be provided on both sides of the line pattern (semi-transmissive portion 501) of the photomask 500 in consideration of a margin for side etching of the workpiece 503 during etching. The bias portions 506a and 506b can be provided using the same material as the semi-transparent film forming the line pattern. Note that the widths (bias values) of the bias portions 506a and 506b may be set based on the etching conditions of the workpiece 503. For example, ½ of the difference between the line width LM and the space width SM of the photomask 500 is set. When the bias value is set, the bias value can be set to 0.2 μm to 1.0 μm.

  The pattern transfer method described above can be applied to a method for manufacturing various electronic devices such as a liquid crystal display device. For example, when a pixel electrode is formed in a strip shape (comb shape) in a liquid crystal display device, the pattern is transferred to a transparent conductive film such as ITO using a photomask 500 having a line-and-space pattern. can do. In this case, a transparent conductive film such as ITO corresponds to the workpiece 503.

  The predetermined transfer pattern including the line and space pattern of the photomask 500 can be formed by patterning a semi-transparent film formed on the transparent substrate 510. At this time, the part that becomes the line pattern of the line-and-space pattern of the photomask 500 leaves the semi-transparent film formed on the transparent substrate 510 to be a semi-transparent part, and the part that becomes the space pattern is The semi-transparent film may be removed to form a translucent part.

  Further, the translucent portion 501 serving as a line pattern has a transmittance of preferably 1% or more and 30% or less, more preferably 1% or more and 20%, when the transmittance of the light transmitting portion of the photomask 500 is 100%. Hereinafter, it can be formed by using a translucent film of 3% or more and 20% or less. The transmittance of the light transmitting portion of the photomask 500 being 100% refers to the case where the transmittance of a sufficiently wide light transmitting portion (a light transmitting portion of 20 μm square or more) in the photomask 500 is 100%.

  Further, the width (line width LM) of the semi-transparent portion 501 and the width (space width SM) of the translucent portion 502 of the line-and-space pattern of the photomask 500 are lines formed on the workpiece 503. It can be determined based on the line width LP and space width SP of the AND space pattern. For example, when the line width LP and the space width SP of the line and space pattern formed on the workpiece 503 are made equal, the line width LM of the photomask 500 is larger than the space width SM (LM> SM). As described above, when etching is performed using the resist pattern 505 as a mask, the workpiece 503 is side-etched, and the line width LP actually formed on the workpiece 503 is the line width LM of the photomask. This is because it becomes smaller.

  The ratio of making the line width LM of the photomask 500 larger than the space width SM takes into account the margin of the side etching of the workpiece 503 during etching, and the line pattern (semi-transparent) of the photomask 500 by that width. What is necessary is just to add a bias part to the both sides of the optical part 501). As described above, when ½ of the difference between the line width LM and the space width SM of the photomask 500 is used as the bias value, the bias value can be set to 0.2 μm to 1.0 μm. For example, when a line-and-space pattern having a bias value of 0.5 μm and a pitch width of 5 μm (a line width and a space width of 2.5 μm) is formed on the workpiece 503, The line width LM can be set to 3.0 μm and the space width SM can be set to 2.0 μm.

  Further, in manufacturing the photomask 500, a database is obtained in advance by grasping correlations such as exposure conditions, resist film characteristics, workpiece characteristics, workpiece processing conditions, etc., and processing the workpiece 503. The photomask 500 can be designed using simulation based on the conditions. As the exposure conditions, the wavelength of exposure light, the NA (numerical aperture) of the imaging system, σ (coherence), and the like may be taken into consideration. As characteristics of the resist film, resist development conditions, resistance to an etchant, and the like may be considered. What is necessary is just to consider the etching conditions (type of etchant, temperature) etc. of a to-be-processed object as a characteristic of a to-be-processed object. As the processing conditions of the workpiece, the shape of the line and space pattern (line width LP and space width SP) formed on the workpiece may be considered.

  These correlations are stored in a database in advance, and simulation is performed based on the processing conditions of the workpiece 503 to be manufactured, whereby the photomask 500 is designed according to design conditions (the semi-transparent film used for the semi-translucent portion 501). Manufacturing time of the photomask 500 can be greatly shortened by obtaining the transmittance, the width of the semi-translucent portion 501 (line width LM), and the width of the translucent portion 502 (space width SM). It becomes.

  The following describes the results of verification by simulation regarding the case of exposing a resist film using a photomask in which a line pattern of a line-and-space pattern is provided in a semi-transparent portion and a space pattern is provided in the transparent portion. To do.

  First, conditions used for the simulation will be described.

Exposure conditions: NA = 0.08, σ = 0.8, exposure wavelength (g line / h line / i line = 1.0 / 1.0 / 1.0)
Resist film: Positive-Novolak Type
Initial film thickness of resist film: 1.5 μm

As simulation software, software (Sentaurus Lithography ^™ ) manufactured by Synopsys was used.

  Next, a photomask will be described.

<Reference Example 1>
Bias part: + 0.5μm
Pitch width of line and space pattern: 6.0 μm (line width: 3.5 μm, space width: 2.5 μm), 5.0 μm (line width: 3.0 μm, space width: 2.0 μm), 4 .4 μm (line width: 2.7 μm, space width: 1.7 μm)
Line pattern transmittance: 3% to 20%

<Reference Example 2>
Bias part: + 0.8μm
Pitch width of line and space pattern: 8.0 μm (line width: 4.3 μm, space width: 2.7 μm), 6.0 μm (line width: 3.8 μm, space width: 2.2 μm), 5 0.0 μm (line width: 3.3 μm, space width: 1.7 μm)
Line pattern transmittance: 3% to 20%

<Reference Comparative Example 1>
Bias part: + 0.5μm
Pitch width of line and space pattern: 8.0 μm (line width: 4.5 μm, space width: 3.5 μm), 7.0 μm (line width: 4.0 μm, space width: 3.0 μm), 6 0.0 μm (line width: 3.5 μm, space width: 2.5 μm), 5.0 μm (line width: 3.0 μm, space width: 2.0 μm), 4.4 μm (line width: 2.7 μm, space width) : 1.7μm)
Line pattern transmittance: 0%

<Reference Comparative Example 2>
Bias part: + 0.8μm
Pitch width of the line and space pattern: 8.0 μm (line width: 4.8 μm, space width: 3.2 μm), 7.0 μm (line width: 4.3 μm, space width: 2.7 μm), 6 0.0 μm (line width: 3.8 μm, space width: 2.2 μm), 5.0 μm (line width: 3.3 μm, space width: 1.7 μm), 4.4 μm (line width: 2.7 μm, space width) : 1.7μm)
Line pattern transmittance: 0%

  First, the relationship between the position of the mask and the effective transmittance of the transmitted light when the exposure light is applied to the photomask on which the line and space pattern is formed will be described.

  FIG. 6 shows the effective transmittance of transmitted light when a photomask (binary mask) in which a line pattern is formed of a light-shielding film having a transmittance of 0 is used. 6A shows a case where the bias portion provided in the light shielding film is 0.5 μm (reference comparative example 1), and FIG. 6B shows that the bias portion provided in the light shielding film is 0. The case of 8 μm (Reference Comparative Example 2) is shown, and FIG. 6C shows a schematic diagram of the line and space pattern used in the simulation. The bias portion was formed using the same material as the film forming the line pattern. 6A and 6B, the horizontal axis indicates the position of the line and space pattern formed on the mask, and the vertical axis indicates the effective transmittance of transmitted light.

  From FIG. 6, it was confirmed that as the pitch width of the line and space pattern was reduced, the transmittance of the transmitted light in the light transmitting portion of the photomask was remarkably reduced.

  7 and 8 show the transmittance of transmitted light when a photomask having a line pattern formed of a semi-transparent film is used. FIG. 7 shows the case where the bias portion provided in the semi-transparent film is 0.5 μm (Reference Example 1), and FIG. 8 shows the case where the bias portion provided in the semi-transparent film is 0.8 μm (Reference Example 2). ). 7A to 7C, the line and space pattern pitch width is 6.0 μm (FIG. 7A), and the pitch width is 5.0 μm. (FIG. 7B) shows a case where the pitch width is 4.4 μm (FIG. 7C). In FIG. 8, FIGS. 8A to 8C are respectively line and space lines. When the pitch width of the pattern is 7.0 μm (FIG. 8A), when the pitch width is 6.0 μm (FIG. 8B), when the pitch width is 5.0 μm (FIG. 8C). Show.

  7 and 8, it was found that the transmittance of the translucent part increases as the transmissivity of the semi-translucent part increases.

  Next, the cross-sectional shape of the resist pattern when the resist film is exposed and developed using a photomask having a line and space pattern will be described.

  9 and 10 show cross sections of the resist pattern after development when a photomask (binary mask) in which a line pattern is formed of a light-shielding film having a transmittance of 0 is used. 9 shows the case where the bias portion provided in the light shielding film is 0.5 μm (Reference Comparative Example 1), and FIG. 10 shows the case where the bias portion provided in the light shielding film is 0.8 μm (Reference Comparative Example 2). ). 9 (A) to 9 (E) and FIGS. 10 (A) to (D) are respectively the case where the pitch width of the line and space pattern is 8.0 μm (FIG. 9 (A) and FIG. A)), when the pitch width is 7.0 μm (FIGS. 9B and 10B), when the pitch width is 6.0 μm (FIGS. 9C and 10C), the pitch width Is 5.0 μm (FIG. 9D, FIG. 10D), and 4.4 μm (FIG. 9E).

  9 and 10 show the cross-sectional shape of the resist pattern after development when the exposure light intensity is constant (100 mJ).

  In FIG. 9, in the case where the pitch width of the line and space pattern is relatively large (8.0 μm, 7.0 μm), the resist of the portion irradiated through the light transmitting part with 100 mJ exposure light Although it was confirmed that the film could be removed, it was confirmed that the resist film remained when the pitch width of the line and space pattern was 6.0 μm or less. When the intensity of exposure light required to completely remove the resist film was obtained, the line width of the line and space pattern was 106.7 mJ when the pitch width was 6.0 μm, and the pitch width was 5.0 μm. In this case, it was necessary to irradiate exposure light of 148.2 mJ when the pitch width was 4.4 μm.

  In FIG. 10, when the pitch width of the line-and-space pattern was 8.0 μm, it was confirmed that the resist film in the portion irradiated through the light-transmitting portion with 100 mJ exposure light could be removed. It was confirmed that the resist film remained when the pitch width of the line and space pattern was 7.0 μm or less. When the intensity of exposure light necessary to completely remove the resist film was obtained, the line width of the line and space pattern was 104.6 mJ when the pitch width was 7.0 μm, and the pitch width was 6.0 μm. However, when the pitch width was 5.0 μm, exposure light of 150.4 mJ had to be irradiated.

  FIGS. 11 to 16 show cross sections of the resist pattern after development when a photomask having a line pattern formed of a semi-transparent film is used. 11 to 13 show the case where the bias portion provided in the semi-transparent film is 0.5 μm (Reference Example 1), and FIGS. 14 to 16 show that the bias portion provided in the semi-transparent film is 0. The case of .8 μm (Reference Example 2) is shown. 11 and 15 show a case where the pitch width of the line and space pattern is 6.0 μm, FIGS. 12 and 16 show a case where the pitch width is 5.0 μm, and FIG. 13 shows a case where the pitch width is 4.4 μm. FIG. 14 shows a case where the pitch width is 7.0 μm.

  11 to 16 show cross sections of the resist pattern after development when the transmissivity of the semi-translucent portion forming the line pattern is changed. However, FIGS. 11 to 16 show cross sections when the exposure light necessary for removing the resist film is irradiated. Tables 1 and 2 show the relationship of the exposure light intensity (exposure intensity necessary for removing the resist film) with respect to the transmittance of the semi-translucent portion for each pitch width. Table 1 shows the case where the bias part is 0.5 μm (Reference Example 1), and Table 2 shows the case where the bias part is 0.8 μm (Reference Example 2).

  From FIG. 11 to FIG. 16, Table 1 and Table 2, as the transmittance of the semi-transparent film is increased, the resist film in the exposed portion is removed, and the intensity of the exposure light necessary to obtain a necessary line width is obtained. It was confirmed that it could be made smaller. Also, as the pitch width of the line-and-space pattern decreases, the intensity of exposure light required to form the resist pattern increases. Compared to the case where the line pattern is formed from a light-shielding film. Thus, it was confirmed that the intensity of exposure light in the photolithography process can be greatly reduced.

  As described above, even when the line pattern of the transfer pattern portion 102 is formed of a semi-transparent film instead of a light shielding film, the pitch width of the line and space pattern of the photomask 100 is reduced. Further, it is possible to suppress a reduction in the intensity of transmitted light irradiated to the resist film through the light transmitting portion 102b (space pattern), and to remove the resist film exposed through the light transmitting portion 102b after development. . This is because the line pattern is formed by the semi-transparent portion 102a, so that an effect equivalent to increasing the exposure amount of the semi-transparent portion in the photolithography process can be obtained, and as a result, the transfer resolution can be increased. This is because it can. When a transfer pattern including line and space is formed on the photomask on the premise of wet etching of the work piece, the line width of the space becomes finer than 1/2 of the pitch and the processing difficulty increases. Even in the production of a photomask, it is possible to form a good pattern. This makes it possible to form a desired fine pattern with an exposure amount that can be applied in a conventional photolithography process (without changing the exposure amount or with a smaller exposure amount).

  A method for manufacturing the photomask shown in FIG. 1 will be described below with reference to the drawings. Note that in this embodiment mode, three methods will be described as photomask manufacturing methods.

<Photomask Manufacturing Method 1>
First, after the light-shielding film 202 is formed over the transparent substrate 101, the first photoresist film 204 is formed over the light-shielding film 202 (see FIG. 2A).

  As the light-shielding film 202, chromium (Cr) or a chromium compound (CrO, CrN, CrC, or the like) can be preferably used, and can be formed by a sputtering method. It is also preferable to provide an antireflection function by laminating CrO, CrN, CrC or the like on a film containing chromium as a main component.

  Next, a light shielding pattern to be formed on the periphery of the photomask (see FIG. 1A) is drawn on the first photoresist film 204 by a drawing machine. At the same time, a mark pattern to be formed on the light shielding pattern is drawn. Thereafter, development is performed to form a first resist pattern 206 (see FIG. 2B), and then the light-shielding film 202 is patterned by wet etching using the first resist pattern 206 as a mask (see FIG. 2C). ). Thereby, the light shielding film pattern 208 and the mark pattern are formed on the transparent substrate 101. In this embodiment, in order to form the mark pattern on the end portion of the transparent substrate 101, the light shielding film pattern 208 is formed in the peripheral region of the transparent substrate 101 and outside the transfer pattern region as shown in FIG.

  Next, after removing the first resist pattern 206, a semi-transparent film 212 is formed over the transparent substrate 101 with the mask 210 provided over the light-shielding film pattern 208 (see FIG. 2D). .

  As the semi-transparent film 212, a Cr compound (CrO, CrN, CrC, or the like) or a metal silicide compound (MoSix, MoSiN, MoSiO, MoSiON, MoSiCO, or the like) can be formed using a sputtering method or the like. In this embodiment, there is no particular limitation on the etching selectivity between the semi-transparent film and the light shielding film.

  Further, when the semi-transparent film 212 is formed, the mask 210 is provided so that the end of the light-shielding film pattern 208 is exposed, so that the semi-transparent film 212 covers the end of the light-shielding film pattern 208. It can be formed (see FIG. 2D). In this way, by forming the semi-transparent film 212 so as to cover the end portion of the light shielding film pattern 208, an alignment margin between patterns in the film forming stage is ensured, and an unintended translucent region is formed on the mask. The effect is to prevent it from occurring.

  Next, after removing the mask 210, a second photoresist film 214 is formed over the semi-transparent film 212 and the light shielding film pattern 208 (see FIG. 2E), and then the second photoresist film 214 is formed. Then, development is performed to form a second resist pattern 216 (see FIG. 2F).

  The shape of the second resist pattern 216 corresponds to the shape of the transfer pattern portion in the photomask. Therefore, when the transfer pattern portion of the photomask is provided as a line and space pattern, the second resist pattern 216 may be formed so as to be a line and space pattern.

  Next, by patterning the semi-transparent film 212 by wet etching using the second resist pattern 216 as a mask (see FIG. 2G), a transfer pattern formed by the semi-transparent portion 102a and the translucent portion 102b. The portion 102 can be formed (see FIG. 2H). FIG. 2 shows a case where a mark pattern forming unit 103 is formed around the transfer pattern unit 102. As described above, the mark pattern is preferably drawn when the first resist pattern is formed, but can also be drawn when the second resist pattern is formed. For example, it is preferable when the light shielding film and the semi-transparent film are both Cr-based films.

  Through the above steps, it is possible to manufacture a binary mask in which a transfer pattern portion is formed of a semi-translucent portion and a translucent portion, and a mark pattern formation portion is formed of a light shielding film. As shown in FIG. 2, even if the semi-transparent film is formed after the light-shielding film is formed, the mark pattern forming unit has a structure in which the semi-transparent film is not formed on the light-shielding film (the light-shielding film is formed). By exposing it, reading errors caused by interference of the semi-transparent film can be suppressed. In addition, when this manufacturing method is adopted by using the manufacturing method shown in FIG. 2, the semi-transparent film is formed in the transfer pattern portion after the process, so that the light shielding pattern (mark pattern already formed) is formed. The mask manufacturing tact can be shortened by producing the photomask blank in advance and performing the remaining steps after determining the product specifications such as the transmissivity of the semi-transparent film.

<Photomask Manufacturing Method 2>
Then, the manufacturing method different from the said manufacturing process 1 is demonstrated with reference to FIG.

  First, a semi-transmissive film 302 is formed over the transparent substrate 101 (see FIG. 3A).

  Next, after the light-shielding film 304 is formed over the semi-light-transmitting film 302, the first photoresist film 306 is formed over the light-shielding film 304 (see FIG. 3B). Although the above-mentioned materials can be applied to the semi-transparent film 302 and the light-shielding film 304, it is preferable to use a material having etching selectivity (the other has resistance in one etching environment). For example, the light shielding film is Cr-based, and the semi-transparent film is metal silicide-based.

  Next, a mark pattern is drawn on the first photoresist film 306 together with the transfer pattern using a drawing machine. Thereafter, development is performed to form a first resist pattern 308 (see FIG. 3C), and then the light-shielding film 304 and the semi-transparent film 302 are patterned using the first resist pattern 308 as a mask (FIG. 3D )reference). Thereby, a patterned light-shielding film and semi-transparent film laminated pattern 310 is formed (see FIG. 3E).

  The laminated pattern 310 of the light shielding film and the semi-transparent film corresponds to the pattern shape of the transfer pattern and the mark pattern in the photomask.

  Next, after removing the first resist pattern 308 (see FIG. 3E), a second photoresist film 312 is formed so as to cover the light-shielding film and the semi-transparent film (see FIG. 3F). ). Then, a light shielding pattern to be formed on the periphery of the photomask outside the transfer pattern portion is drawn on the second photoresist film 312 and then developed to form a second resist pattern 314 (FIG. 3G). reference).

  The second resist pattern 314 is formed so as to cover the already formed mark pattern region and to expose a region to be a transfer pattern portion of the photomask (here, the laminated pattern 310 of the light shielding film and the semi-transparent film). To do.

  Next, the light-shielding film formed over the semi-transparent film is etched away using the second resist pattern 314 (see FIG. 3H), so that the semi-transparent part 102a and the translucent part 102b are formed. The transfer pattern portion 102 and the mark pattern 103 to be formed can be formed (see FIG. 3I).

  Through the above steps, it is possible to manufacture a binary mask in which the transfer pattern portion is formed of a semi-translucent portion and a translucent portion, and the mark pattern formation portion is formed of the light transmissive portion and the light shielding portion where the light shielding film is exposed. By using the manufacturing method shown in FIG. 3, since the film forming step is not sandwiched between the first and second patterning, the manufacturing tact after the patterning start can be shortened.

<Photomask Manufacturing Method 3>
Next, a manufacturing method different from the manufacturing steps 1 and 2 will be described with reference to FIG.

  First, the semi-transparent film 402 is formed with the mask 404 provided over the transparent substrate 101 (see FIG. 4A). The mask 404 may be provided at least in a region where a mark pattern formation portion is formed.

  Next, after removing the mask 404, a light shielding film 406 is formed over the semi-transparent film 402 and the exposed transparent substrate 101 (see FIG. 4B), and then the first photoresist is formed over the light shielding film 406. A film 408 is formed (see FIG. 4C). The materials for the semi-transparent film and the light-shielding film can be the same as those in the manufacturing method 2.

  Next, after pattern data for forming a transfer pattern and a mark pattern is drawn on the first photoresist film 408 and developed to form a first resist pattern 410 (see FIG. 4D), The light shielding film 406 and the semi-transparent film 402 are patterned using the first resist pattern 410 as a mask (see FIG. 4E). As a result, a patterned light-shielding film and semi-transparent film laminated pattern 412 is formed (see FIG. 4F).

  The laminated pattern 412 of the light shielding film and the semi-transparent film corresponds to the pattern shape and mark pattern of the transfer pattern portion in the photomask.

  Next, after removing the first resist pattern 410 (see FIG. 4F), a second photoresist film 414 is formed so as to cover the light-shielding film and the semi-transmissive film (see FIG. 4G). ). Then, the second photoresist film 414 is drawn and then developed to form a second resist pattern 416 (see FIG. 4H).

  The second resist pattern 416 is formed so as to cover a region serving as a mark pattern forming portion and to expose a region serving as a transfer pattern portion of the photomask (here, a laminated pattern 412 of a light shielding film and a semi-transparent film). To do.

  Next, the light-shielding film formed on the semi-transparent film is removed using the second resist pattern 416 (see FIG. 4I), so that the semi-transparent part 102a and the translucent part 102b are formed. The transfer pattern portion 102 can be formed (see FIG. 4J).

  Through the above steps, it is possible to manufacture a binary mask in which a transfer pattern portion is formed of a semi-translucent portion and a translucent portion, and a mark pattern formation portion is formed of a light shielding film. By using the manufacturing method shown in FIG. 4, since the film forming process is not sandwiched between the first and second patterning, the manufacturing tact after starting patterning can be shortened. In addition, since the film lamination structure of the mark pattern forming portion is completely the same as that of the binary mask (in the manufacturing method 2, a semi-transparent film remains between the light-shielding film and the substrate), for example, the alignment mark is formed on the mask glass surface (pattern No error occurs when reading from the back of the forming part.

  In addition, this invention is not limited to the said embodiment, It can implement by changing suitably. For example, the material, the pattern configuration, the number of members, the size, the processing procedure, and the like in the above embodiment are merely examples, and various modifications can be made within the scope of the effects of the present invention. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  According to the present invention, a fine line-and-space pattern can be formed even under exposure conditions using a broad wavelength range of i-line to g-line, and even when there is a restriction of etching by wet etching. It solves the problem of manufacturing with high width accuracy. In line and space, even though the space line width is very small, precise processing is possible. This achieves miniaturization from a viewpoint different from the LSI manufacturing field, which has adopted a short wavelength and a phase shift effect by a single wavelength, and is an existing binary mask used in the liquid crystal device manufacturing field. This is significant in that it can be handled in the same way (alignment and mask management). This makes it possible to make a great contribution to reducing the price of liquid crystal display devices.

DESCRIPTION OF SYMBOLS 100 Photomask 101 Transparent substrate 102 Transfer pattern part 102a Semi-light-transmitting part 102b Light-transmitting part 103 Mark pattern formation part 105 Alignment mark 106 Barcode 500 Photomask 501 Semi-light-transmitting part 502 Light-transmitting part 503 Workpiece 504 Resist film 505 Resist pattern 506a Bias part 506b Bias part 510 Transparent substrate

Claims (10)

A photomask for manufacturing a liquid crystal display device having a transfer pattern for transferring to a resist film formed on a workpiece to be etched,
In the transfer region of the photomask, a transfer pattern including a line-and-space pattern made up of a translucent part and a semi-transparent part obtained by patterning a semi-transparent film formed on a transparent substrate is provided. Have
A photomask having a mark pattern obtained by patterning a light-shielding film formed on the transparent substrate outside the transfer region of the photomask.   The photomask according to claim 1, wherein the transfer pattern is for forming a transparent electrode by wet etching.   The photomask forms a line-and-space pattern having the same line width LP and space width SP on the workpiece by etching, and the transfer pattern of the photomask has a line width LM. The photomask according to claim 1, wherein the photomask includes a line and space pattern larger than the space width SM.   4. The photomask according to claim 1, wherein the line-and-space pattern has a pitch, which is a sum of line widths of lines and spaces, of 2 μm or more and less than 7 μm. 5.   5. The photomask according to claim 1, wherein the mark pattern includes a light-transmitting portion from which the transparent substrate is exposed and a light-shielding portion from which the light-shielding film is exposed.   The photo according to any one of claims 1 to 4, wherein the transmissivity of the semi-translucent part is 1% or more and 30% or less when the transmissivity of the translucent part is 100%. mask. A method for producing a photomask having a transfer pattern including a line and space pattern in a transfer region, and having a mark pattern outside the transfer region,
Forming a light shielding film on a transparent substrate;
Patterning the light shielding film to remove the light shielding film in the transfer region and forming a mark pattern outside the transfer region;
A step of forming a translucent film on the transparent substrate in a state where a mask is provided on the mark pattern;
And a step of patterning the semi-transparent film to form the transfer pattern formed by a translucent part and a semi-translucent part. A method for producing a photomask having a transfer pattern including a line and space pattern in a transfer region, and having a mark pattern outside the transfer region,
Forming a translucent film on a transparent substrate;
Forming a light shielding film on the semi-transparent film;
A first resist pattern is formed by drawing and developing the transfer pattern and the mark pattern on a resist film formed on the light shielding film, and the light shielding film and the half pattern are formed using the first resist pattern. Forming a laminated pattern of the light-shielding film and the semi-transparent film by patterning the light-transmitting film;
Forming a second resist pattern so as to expose a laminated pattern of the light-shielding film and the semi-transparent film located in the transfer region after removing the first resist pattern;
By removing the light shielding film formed on the semi-transparent film using the second resist pattern, the transfer pattern formed from the translucent part and the semi-translucent part and the translucent part are exposed. And a step of forming a mark pattern formed from the light-shielding film pattern. A method for producing a photomask having a transfer pattern including a line and space pattern in a transfer region, and having a mark pattern outside the transfer region,
Forming a translucent film with a mask provided outside the transfer region on the transparent substrate; and
Forming a light-shielding film on the semi-transparent film and the exposed transparent substrate;
A first resist pattern is formed by drawing and developing the transfer pattern and the mark pattern on a resist film formed on the light shielding film, and the light shielding film and the half pattern are formed using the first resist pattern. Patterning a light transmissive film to form a laminated pattern of the light shielding film and the semi-light transmissive film in the transfer region, and forming a light shielding film pattern outside the transfer region;
After removing the first resist pattern, forming a second resist pattern so that the laminated pattern of the transfer region is exposed;
By removing the light shielding film formed on the semi-transparent film using the second resist pattern, a transfer pattern formed from the translucent part and the semi-transparent part, the translucent part and the light shielding film And a step of forming a mark pattern formed from the pattern.   Using the photomask according to any one of claims 1 to 6 or the photomask according to the manufacturing method according to any one of claims 7 to 9, an i line to g is applied to a resist film on a workpiece. A pattern transfer method characterized in that a pattern having the same line and space width is processed by performing exposure with an exposure machine having an exposure light source in a range of lines and performing wet etching using the obtained resist pattern.

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