JP6189242B2 - Photomask manufacturing method, photomask and display device manufacturing method - Google Patents

Description

  The present invention relates to a photomask having a transfer pattern and a method for manufacturing the photomask, and more particularly to a photomask useful for manufacturing a display device. The present invention also relates to a method for manufacturing a display device using the photomask.

  With the increase in definition of electronic device products such as display devices, there is an increasing demand for better dimensional control of film patterns included in photomasks used for manufacturing them.

  In relation to this, Patent Document 1 describes a method for more accurately controlling the size of the light shielding film. That is, the light shielding film is etched using the resist pattern as a mask. After the light shielding film not covered with the resist pattern is removed and the etching is stopped, light is irradiated from the back surface of the substrate to expose the resist not shielded by the light shielding film. In addition, a method is described in which the edge position of the light shielding film is grasped by developing and the additional etching time is determined.

  Further, as a photomask manufacturing method for obtaining a gray-tone mask having high uniformity in shape and the like in a repeated pattern region and less unevenness, for example, Patent Document 2 discloses a scanning direction (Y direction) of a head of a drawing apparatus. In a photomask manufacturing method including a drawing step of drawing in a predetermined scan unit to and a predetermined feed unit in a direction perpendicular to the scan direction (X direction), the photomask pattern includes a repetitive pattern. The photomask manufacturing method is characterized in that the drawing step includes a step of drawing each pattern unit under the same feeding condition with respect to a pattern unit including the same repetitive pattern.

JP 2010-169750 A JP 2002-244272 A

  The image quality and brightness required for display devices (liquid crystal display devices, organic EL display devices, and the like), the speed of operation speed, and the level of power saving performance are higher than ever. In view of this situation, it is necessary to miniaturize and increase the density of photomask transfer patterns used in these productions.

  In manufacturing a display device, a photomask having a desired transfer pattern is manufactured using a photolithography process. That is, a resist film is formed on an optical film formed on a transparent substrate, drawn on the resist film with energy rays (laser light, etc.) and developed, and the resist pattern obtained as a mask is used as an optical film. Etch. If necessary, another optical film is formed, and the photolithography process is repeated to form a final transfer pattern. The optical film here includes, for example, a light-shielding film that shields exposure light to the photomask, a semi-transparent film that partially transmits, or a functional film such as a phase shift film and an etching stopper film.

  The photomask for manufacturing a display device has a larger size (for example, 300 mm or more per side) than a photomask for semiconductor manufacturing (generally, 5 to 6 inches per side). Has advantages in that the load on the apparatus and process is small and control is easy when wet etching is applied, rather than dry etching which requires a vacuum chamber.

  On the other hand, there is a difficulty derived from wet etching. In general, dry etching has the property of anisotropic etching, whereas wet etching has a strong characteristic of isotropic etching, in which etching proceeds isotropically. Therefore, also from the side of the optical film to be etched. Etching (side etching) proceeds. FIG. 11 is an SEM photograph showing a state in which the side surface of the light shielding film, which is an optical film, is etched by wet etching. For this reason, the dimension of the etched optical film pattern does not necessarily match the dimension of the resist pattern serving as an etching mask. When etching is performed for a predetermined time, the edge of the optical film pattern advances to the inside of the edge position of the resist pattern and is covered with the resist pattern, so that the dimension cannot be directly measured. Therefore, it is difficult to determine the end point of etching (see FIG. 11).

  Even if the etching rate (the amount of etching per unit time) can be grasped in order to reach a desired pattern dimension, it is not always effective to determine the time required for etching depending only on this. For example, a resist pattern that serves as an etching mask during wet etching is affected by variations and nonuniformity in the resist development temperature and developer concentration, and it is difficult to keep them constant.

  Further, although the edge shape of the resist pattern is formed by drawing, it has been found that the film thickness of the resist pattern and the surface reflectance of the optical film affect the drawing conditions. However, it is not easy to always make the resist pattern film thickness and the optical film surface property constant values.

  In other words, factors other than the pure etching rate derived from the optical film and the etchant, in particular, fluctuation factors due to the resist, are unavoidable in the actual progress of etching when the optical film is wet etched.

  Considering the above situation, in order to perform patterning with high dimensional accuracy, an accurate etching time (that is, an etching time required for a necessary residual etching amount) until the etching end point is obtained regardless of the influence of the above fluctuation factors. It is useful to know.

  In the method of Patent Document 1, the etching is stopped after the light shielding film that is not covered with the resist pattern is removed after the start of etching of the light shielding film, and the edges of the resist pattern and the light shielding film are matched by light irradiation from the back surface, By grasping the edge position, the additional etching time is determined. According to this method, since the position of the edge of the light shielding film covered with the resist pattern can be grasped, there is an effect that a necessary additional etching amount, that is, an additional etching time can be obtained. However, there is an inconvenience that it is difficult to obtain sufficient accuracy for grasping the position of the light shielding film edge in a state where it is laminated with the resist pattern.

  By the way, display devices typified by liquid crystal display devices tend to increase those having a finer structure than before. This is a tendency common to thin film transistor (TFT) substrates, color filters (black matrix, photo spacers, color plates), etc., but in these display devices, image definition, speed of operation, brightness, power saving It is related to needs such as.

  As a result, the CD (Critical Dimension: hereinafter used in the meaning of pattern line width; hereinafter also referred to as “CD value”) of a transfer pattern of a photomask for manufacturing a display device has become more demanding. Until now, in order to improve the CD accuracy, efforts have been made to suppress variations in CD values in each process (drawing, resist development, etching, etc.) necessary for photomask manufacturing.

  However, in recent display devices, for example, a line and space pattern including a line width portion of 2 μm or less is required, and the transferability margin for transferring to a transfer target (liquid crystal panel substrate, etc.) is also required. It is extremely small.

  For example, it is desired that the CD accuracy of the transfer pattern is set to a target value ± 50 nm or less, and further to a target value ± 20 nm or less.

  In order to satisfy these requirements, in-plane CD value variations in the formation of a transfer pattern must be suppressed, and the absolute value must be finished to the limit as designed. In other words, the center value of the CD value of the formed transfer pattern needs to match the target value with high accuracy. Therefore, an object of the present invention is to obtain a photomask manufacturing method capable of forming a transfer pattern with high dimensional accuracy.

  In order to solve the above-described problem, in the isotropic etching in the photomask manufacturing method, the CD center value of the dimension of the optical film to be patterned reaches the target value, and at the same time, the etching is stopped. Therefore, it is important to accurately detect the timing for stopping etching (end point detection).

  In order to solve the above problems, the present invention has the following configuration. The present invention is a photomask manufacturing method characterized by the following configurations 1 to 11, a photomask characterized by the following configuration 12, and a display characterized by the following configuration 13 It is a manufacturing method of an apparatus.

(Configuration 1)
Configuration 1 of the present invention includes
A method for producing a photomask comprising a transfer pattern obtained by patterning an optical film on a transparent substrate,
Preparing a photomask substrate having the optical film and a resist film on the transparent substrate;
A drawing process for drawing on the resist film based on predetermined pattern data using a drawing apparatus;
A resist pattern forming step of forming a resist pattern by developing the resist film;
An optical film patterning step of obtaining the transfer pattern by forming an optical film pattern by etching the optical film using the resist pattern as a mask;
In the drawing step, drawing is performed using the pattern data including the monitor pattern data for forming the monitor pattern for dimension measurement together with the transfer pattern data for forming the transfer pattern to be obtained. ,
The optical film patterning step includes
A first etching that etches the optical film for a predetermined time; and
Measuring the dimensions of the monitor pattern;
A second etching that performs additional etching on the optical film based on the dimensions of the monitor pattern obtained by the dimension measurement;
Including
The monitor pattern includes a CD measurement unit having the same dimensions as the CD guarantee unit and drawn under the same drawing conditions as the CD guarantee unit when at least a part of the transfer pattern is a CD guarantee unit,
The drawing conditions include at least one selected from an X-direction beam array and a Y-direction scan position of an energy beam used for drawing,
In the photomask manufacturing method, the dimension measurement is performed on the CD measurement unit.

(Configuration 2)
Configuration 2 of the present invention is the photomask manufacturing method according to Configuration 1, wherein the first etching and the second etching are wet etching.

(Configuration 3)
The third aspect of the present invention is the photomask manufacturing method according to the first or second aspect, wherein, in the dimension measurement, the resist film in a portion where the monitor pattern is formed is partially removed. is there.

(Configuration 4)
Configuration 4 of the present invention is characterized in that a plurality of the monitor patterns are arranged outside the region of the transfer pattern on the transparent substrate, and each of the plurality of monitor patterns has the CD measurement unit. It is the manufacturing method of the photomask in any one of the structures 1-3.

(Configuration 5)
According to the fifth aspect of the present invention, the transfer pattern includes a repetitive portion where a unit pattern is repeated, and the monitor pattern includes the unit pattern included in the transfer pattern, the dimension in the X direction or the Y direction. 5. The photomask manufacturing method according to any one of Structures 1 to 4, further comprising a repeating portion in which unit patterns having equal portions are repeated.

(Configuration 6)
According to Structure 6 of the present invention, the transfer pattern includes the repeated portion where the unit pattern is repeated, and the monitor pattern includes a repeated portion where the same unit pattern as that included in the transfer pattern is repeated. It is a manufacturing method of the photomask in any one of the structures 1-5 characterized by including.

(Configuration 7)
In the configuration 7 of the present invention, the drawing step has a drawing repetition period in the X direction in which the predetermined drawing conditions are repeated in the X direction, and the beam arrangement is repeated every drawing repetition period in the X direction. A method for producing a photomask according to any one of configurations 1 to 6, wherein:

(Configuration 8)
In the configuration 8 of the present invention, the drawing step has a Y-direction drawing repetition cycle in which a predetermined drawing condition is repeated in the Y direction, and the scan position is repeated every Y-direction drawing repetition cycle. A method for producing a photomask according to any one of Structures 1 to 7, wherein:

(Configuration 9)
According to the ninth aspect of the present invention, the least common multiple of the drawing repetition period in the X direction in the drawing step and the pitch in the X direction of the unit pattern is an integer of 20 or less. It is a manufacturing method of the described photomask.

(Configuration 10)
The configuration 10 of the present invention is characterized in that the least common multiple of the drawing repetition period in the Y direction in the drawing step and the pitch in the Y direction of the unit pattern is an integer of 20 or less. It is a manufacturing method of the described photomask.

(Configuration 11)
Configuration 11 of the present invention is the photomask manufacturing method according to any one of Configurations 1 to 10, wherein the transfer pattern is a pattern for manufacturing a display device.

(Configuration 12)
Configuration 12 of the present invention is a photomask including a transfer pattern obtained by patterning an optical film and a plurality of monitor patterns on a transparent substrate,
The monitor pattern is provided outside the transfer pattern area,
When at least a part of the transfer pattern is a CD guarantee part, the monitor pattern has a CD measurement part having the same dimensions as the CD guarantee part and formed under the same drawing conditions as the CD guarantee part. ,
The photomask is characterized in that the drawing condition is at least one of an X-direction beam arrangement or a Y-direction scan position of an energy beam used for drawing the transfer pattern.

(Configuration 13)
According to the thirteenth aspect of the present invention, the transfer pattern of the photomask is transferred onto the transfer object using the step of preparing the photomask by the manufacturing method according to any one of the first to eleventh aspects and the exposure apparatus. A method for manufacturing a display device.

  According to the photomask manufacturing method of the present invention, a transfer pattern with high dimensional accuracy can be formed.

It is an example (right side) of the manufacturing method flow (left side) of the one aspect | mode of the manufacturing method of the photomask of this invention, and the cross-sectional schematic diagram of the state of the optical film on the transparent substrate in each process of manufacturing method flow. It is a figure which shows an example of the variation | change_quantity of CD with respect to etching time for calculating | requiring additional etching time. FIG. 3A is an example of a schematic diagram of a pattern formed on the main surface of a photomask for manufacturing a display device. FIG. 3B is an enlarged schematic diagram of a transfer pattern among the patterns shown in FIG. FIG. 3C is an enlarged schematic diagram of a monitor pattern among the patterns shown in FIG. FIG. 4A is an example of a schematic view of another aspect of a pattern formed on the main surface of a photomask for manufacturing a display device. FIG. 4B is an enlarged schematic diagram of a transfer pattern among the patterns shown in FIG. FIG. 4C is an enlarged schematic diagram of a monitor pattern among the patterns shown in FIG. FIG. 5A is an example of a schematic view of still another aspect of the pattern formed on the main surface of the photomask for manufacturing the display device. FIG. 5B is an enlarged schematic diagram of a transfer pattern among the patterns shown in FIG. FIG. 5C is an enlarged schematic diagram of a monitor pattern among the patterns shown in FIG. FIG. 6A is an example of a schematic diagram of an aspect in which OPC (optical proximity correction) is arranged in a pattern formed on the main surface of a photomask for manufacturing a display device. FIG. 6B is an enlarged schematic diagram of a transfer pattern among the patterns shown in FIG. FIG. 6C is an enlarged schematic diagram of a monitor pattern among the patterns shown in FIG. It is a schematic diagram which shows an example of the motion of the laser beam irradiated from the drawing head in a laser drawing apparatus. It is a schematic diagram which shows an example of the motion of the laser beam irradiated from the drawing head of a laser drawing apparatus. It is a schematic diagram which shows an example of the method of the line | wire width (CD) control in the Y direction by the laser beam irradiated from the drawing head of a laser drawing apparatus. It is a schematic diagram for explaining that the CD (line width) of the pattern in the X direction is determined by the irradiation intensity of light by the laser beam (beam diameter A μm) irradiated from the drawing head of the laser drawing apparatus. It is a SEM photograph which shows the state by which the side surface of the light shielding film which is an optical film was etched by wet etching.

  The present invention is a photomask manufacturing method comprising a transfer pattern obtained by patterning an optical film on a transparent substrate. The method for producing a photomask of the present invention comprises a step of preparing a photomask substrate having the optical film and a resist film on the transparent substrate, and a predetermined pattern data for the resist film using a drawing apparatus. An optical film pattern is formed by etching the optical film using the resist pattern as a mask, and a resist pattern forming process that forms a resist pattern by developing the resist film and developing the resist film And an optical film patterning step for obtaining the transfer pattern. In the drawing step, drawing is performed using the pattern data including monitor pattern data for forming a monitor pattern for dimension measurement together with transfer pattern data for forming the transfer pattern to be obtained. . In the optical film patterning step, the optical film is etched for a predetermined time, based on the first etching, the dimension measurement of the monitor pattern, and the dimension of the monitor pattern obtained by the dimension measurement, And a second etching for performing additional etching on the optical film. The monitor pattern includes a CD measurement unit having the same dimensions as the CD guarantee unit and drawn under the same drawing conditions as the CD guarantee unit when at least a part of the transfer pattern is a CD guarantee unit. The drawing condition includes at least one selected from an X-direction beam array and a Y-direction scan position of an energy beam used for drawing. The dimension measurement is performed on the CD measurement unit.

  An embodiment of the photomask manufacturing method of the present invention will be described with reference to a manufacturing method flow shown in FIG. On the right side of the flow shown in FIG. 1, the state of the optical film on the transparent substrate in each step is illustrated as a schematic cross-sectional view. In the figure, reference numeral 1 is a transparent substrate, reference numeral 2 is an optical film, reference numerals 2a and 2b are optical film patterns, reference numeral 3 is a resist film, reference numerals 3a and 3b are resist patterns, and reference numeral 6 is a laser for laser drawing. Showing beam. The optical film pattern 2a indicates a pattern corresponding to a transfer pattern, and the optical film pattern 2b indicates a pattern corresponding to a monitor pattern. Similarly, the resist pattern denoted by reference numeral 3a indicates a portion where a transfer pattern is formed, and indicates a resist pattern denoted by reference numeral 3b (a portion where a monitor pattern is formed).

(A) Step of Preparing Photomask Substrate The photomask substrate that can be used in the photomask manufacturing method of the present invention has an optical film formed on a transparent substrate, and a photoresist film (hereinafter referred to as a “photoresist film” on the surface). A photomask blank in which a photoresist film is also simply referred to as a resist film) can be obtained. The optical film may be a single layer or a plurality of films may be laminated.

  The photomask substrate of the present invention is a photomask intermediate in which a part of the optical film is already patterned for the purpose of manufacturing a photomask having a film pattern of a laminated structure, and further, the pattern is not formed. In order to perform patterning on the optical film, a resist film may be formed.

(Optical film)
In the step of preparing the photomask substrate, an optical film is formed on the first main surface of the transparent substrate by a known film formation method such as sputtering.

  As the optical film, for example, a light shielding film (optical density OD with respect to exposure light when using a photomask is 3 or more) can be used. The optical film may be a semi-transparent film or a transparent film that partially transmits exposure light. The exposure light transmittance of the semi-transparent film is 3 to 60% based on the transmittance of the transparent substrate (100%).

  The optical film can be, for example, a phase shift film that has a transmittance of 3 to 30% for exposure light and inverts (shifts approximately 180 degrees) the phase of the representative wavelength contained in the exposure light. About 180 degrees means an angle in the range of 150 to 210 degrees.

  Furthermore, the optical film is a semi-transparent film that has a light transmittance of 3 to 60% with respect to the exposure light and shifts the phase of the representative wavelength contained in the exposure light within a range of 5 to 90 degrees. Can do. Such a semi-transparent film is used instead of the light shielding film or together with the light shielding film when forming a fine space pattern or hole pattern, to assist the amount of light transmitted through the photomask, and to form a resist on the transferred object. The light quantity auxiliary pattern used for the purpose of reaching the photosensitive threshold value can be obtained.

  The film thickness of the optical film is determined by its function, but is preferably 5 to 250 nm. For example, in the case of a light shielding film in a binary mask, the thickness of the light shielding film can be set to 50 to 200 nm.

  The optical film can be wet-etched. The material of the optical film can include, for example, chromium (Cr). Alternatively, it can be a translucent film made of a chromium compound. In the case of a semi-transparent film having the transmittance and the phase shift amount as described above, it may be a film containing any of chromium oxide, nitride, carbide, oxynitride, and oxynitride carbide. it can.

  Furthermore, an optical film made of a metal other than chromium, for example, Mo, Ta, W, Zr, Nb, Ti, or a compound thereof can also be applied. The material of the optical film can be, for example, a material containing metal silicide or its oxide, nitride, carbide, oxynitride, or oxynitride carbide. Examples of the metal silicide that can be used as the material of the optical film include molybdenum silicide and tantalum silicide.

  The optical film preferably has an antireflection layer on the surface for suppressing light reflectance. In that case, for example, the antireflection layer disposed on the surface of the optical film mainly composed of chromium is composed of a chromium compound (oxide, nitride, carbide, etc.), the surface layer being composed in the thickness direction of the optical film. It is preferable to change. The composition change may be a step change or a slow change. This antireflection layer has a function of suppressing reflection with respect to exposure light used when using a photomask, but also has an action of suppressing surface reflection in dimension measurement described later.

(Resist film)
As a photomask substrate used in the method for producing a photomask of the present invention, a substrate in which a resist film is formed on an optical film can be used. A resist serving as a raw material for the resist film can be applied onto the transparent substrate by a known coating apparatus such as a slit coater or a spin coater. The film thickness of the resist film is preferably 300 to 1000 nm.

  Here, the resist film will be described as a positive photoresist for laser drawing. However, a negative type may be used. Further, when drawing is performed with an electron beam, an electron beam resist may be used.

  Furthermore, in the photomask manufacturing method of the present invention, pattern data for drawing on the resist film is prepared. The drawing pattern data includes transfer pattern data designed based on the device to be obtained, and further includes monitor pattern data for forming a monitor pattern for CD measurement described later.

  The transfer pattern data and the monitor pattern data included in the drawing pattern data used in the present invention are subjected to a predetermined amount of sizing (so-called sizing) on the target CD of the optical film pattern to be formed. Is preferred. Thus, before additional etching (second etching), which will be described later, the etching is surely undertaken (the removal dimension of the optical film is small), and a tolerance is obtained. This size processing is preferably performed on the under side by about 30 to 100 nm with respect to the tolerance (for example, 50 to 300 nm) given to a normal resist pattern. Details of the transfer pattern and the monitor pattern will be described later.

(B) Drawing process In the manufacturing method of the photomask of this invention, it draws with respect to the resist film of a photomask substrate. The drawing pattern data is used when drawing on the resist film. As a drawing apparatus for drawing, an FPD laser drawing machine using laser light (wavelength of about 413 nm) as a light source can be used.

  In the photomask manufacturing method of the present invention, as described above, the predetermined pattern data for drawing forms a monitor pattern for dimension measurement together with transfer pattern data for forming a transfer pattern to be obtained. Monitor pattern data. Therefore, the transfer pattern and the monitor pattern are drawn in the same drawing process.

(C) Resist pattern formation process In the photomask manufacturing method of the present invention, a resist pattern is formed by developing the resist film on the surface of the optical film. This resist pattern functions as an etching mask when the optical film is etched.

(D) Optical Film Patterning Step (d-1) First Etching In the photomask manufacturing method of the present invention, the first etching is performed for a predetermined time on the optical film using the resist pattern as a mask. The first etching is wet etching, and an appropriate etching agent (etching solution) can be selected according to the composition of the optical film. Both the first etching and the second etching described later are preferably wet etching. For example, when the optical film is a chromium-based light shielding film, an etching solution containing ceric ammonium nitrate can be used. The etching solution first acts on the surface of the optical film that is not covered with the resist pattern, thereby starting the elution of the optical film in that portion. However, after the portion of the optical film not covered with the resist pattern has been eluted, etching from the side surface of the optical film proceeds by isotropic etching. In the first etching, the optical film is etched for a period of time until the portion of the optical film not covered with the resist pattern substantially disappears, and is temporarily stopped. For example, the first etching time may be about 50 to 120 seconds.

(D-2) Dimensional measurement of monitor pattern When the first etching on the optical film is stopped, the edge of the patterned optical film is at the same position as the edge of the resist pattern, or from the edge of the resist pattern Although there may be a position inside (that is, a state where the edge position of the optical film is under the resist pattern), the dimension of the optical film pattern after the first etching can be measured by the following method. .

  Note that, during the wet etching of the optical film, side etching of the optical film proceeds, but the etching rate of the optical film at this time is substantially constant. Accordingly, the edge position of the optical film recedes in proportion to the etching time, and the CD of the optical film pattern changes (decreases). The correlation between the CD change amount and the etching time can be experimentally obtained in advance. For example, as shown in FIG. 2, the change amount of CD with respect to the etching time when optical films having the same film thickness and the same composition are side-etched under the same conditions is measured and grasped in advance. In the example shown in FIG. 2, the etching rate of the optical film under a predetermined condition is 8 nm / second.

  In the photomask manufacturing method of the present invention, the dimension of the monitor pattern, that is, the CD, is measured on the photomask substrate where the first etching is stopped. For this reason, the resist pattern on the monitor pattern is peeled off to expose the measurement target portion of the monitor pattern. Specifically, for example, spot exposure is performed on a portion of the resist pattern on the monitor pattern, and a developer is brought into contact therewith to remove the resist in this portion. As a result, the monitor pattern made of the optical film is exposed.

  In the dimension measurement, by partially removing the resist film in the part where the monitor pattern is formed, the dimension of the monitor pattern can be measured directly from the surface side, so that optical measurement can be performed with high accuracy. The dimension of the monitor pattern can be measured by transmission using light having a wavelength of 400 to 600 nm with a line width measuring device.

  The portion to be measured as the dimension of the monitor pattern is a portion (referred to as a measurement portion) corresponding to a portion (hereinafter referred to as a guarantee portion) that guarantees the CD value in the transfer pattern, that is, a CD guarantee portion. It is preferable to include portions of the same dimensions. For this reason, the measurement result of the dimension of the monitor pattern reflects the CD value of the guarantee part of the transfer pattern corresponding to the measurement part.

  Then, the difference between the measured CD value and the target CD value is grasped, and necessary addition is made from the difference and the value of the etching rate of the optical film that is grasped in advance (see FIG. 2). Etching time can be calculated.

  When the monitor pattern after the measurement is subjected to additional etching thereafter, both the etching of the exposed surface and the side etching proceed. For this reason, the surface reflectance of the optical film may change or the optical film may be damaged. However, since the monitor pattern is not a pattern used for the final product, there is no problem.

  In addition, in order to avoid damage to the monitor pattern, a masking material may be applied or applied after the dimension measurement so that the optical film does not come into contact with the etching solution during the additional etching.

(D-3) Second etching In order to obtain a pattern for transferring a target CD value, additional etching (that is, second etching) is performed for the additional etching time obtained as described above. The second etching is preferably wet etching. Note that since the edge to be etched of the optical film has already approached the position of the target dimension, even if additional etching is required, the additional etching time may be short. Preferably, the additional etching time can be an etching time of 0 to 10 seconds.

(E) Cleaning process After the second etching for the additional etching time is completed, the etching is stopped again, and the resist pattern is peeled off and cleaned.

  Even if there are various unstable elements in the formation of the resist pattern serving as an etching mask by the above method, the dimensions of the optical film pattern (transfer pattern) to be finally formed are surely set to the predetermined specifications. It becomes possible to match.

(F) Inspection process The formed transfer pattern is inspected for the CD value and the like. In addition, other inspections are performed to confirm the quality of the transfer pattern.

  In the above aspect, the measurement of the monitor pattern dimension is performed only once. However, if necessary, the measurement of the dimension of the monitor pattern and the second etching may be repeated, and such an embodiment is also included in the present invention.

  The transfer pattern and monitor pattern formed on the photomask will be described in more detail. In a photomask for manufacturing a display device, a transfer pattern including a repetitive pattern necessary for a structure such as a thin film transistor or a color filter is formed. An example is shown in FIG. FIG. 3A is an example of a schematic view of the main surface of the photomask of the present invention. The actual pattern shape is not always the same.

  As shown in FIG. 3A, in the photomask of this aspect, two transfer patterns for manufacturing the display device are arranged in the center of the main surface of the transparent substrate, and the monitor pattern is outside the transfer pattern area. Are provided. In the photomask manufacturing method of the present invention, it is preferable that a plurality of monitor patterns are disposed outside the transfer pattern region on the transparent substrate, and each of the plurality of monitor patterns has a CD measurement unit. These eight monitor patterns preferably have a size of about 0.2 to 10 mm in both the X direction and the Y direction, and more preferably 0.5 to 10 mm. There is no limitation on the number of monitor patterns formed on the photomask of the present invention. The number of monitor patterns is preferably 2 to 12. If the etching behavior is not uniform in the plane with multiple monitor patterns, grasp the tendency, or process the measurement results of multiple monitor patterns (for example, calculate the average value), etc. By performing highly accurate additional etching (second etching), it is possible to obtain a transfer pattern with higher reliability.

  The positions of the plurality of monitor patterns are preferably arranged apart from each other at positions near the corners and sides of the transparent substrate outside the transfer pattern area. For example, it can be arranged near each of the four corners of the transparent substrate, or can be arranged near each of the four sides. When the monitor patterns are separated (for example, arranged with a separation distance of 1/4 or more of the short side of the transparent substrate), slight in-plane non-uniformity occurs in the patterning of the optical film on the substrate. You can even figure this out.

  In this aspect, the transfer pattern includes a pixel pattern portion having a pixel pattern used for a liquid crystal display device. The pixel pattern portion includes, for example, a repetitive portion in which a plurality of unit patterns having the same shape with a pixel pattern of one pixel as a unit are regularly arranged (see FIG. 3B).

  In the present specification, the unit pattern refers to a unit pattern that is repeatedly repeated. The unit pattern may be a minimum unit pattern (for example, a pixel pattern for one pixel in a pattern for a display device), or a plurality of (for example, 2 to 5 units each in the X and / or Y direction) array. It may be

  In the monitor pattern, a plurality of unit patterns that are the same as the unit patterns included in the transfer pattern are arranged with regularity in the same manner as the arrangement of the unit patterns in the transfer pattern (see FIG. 3C). ). The unit pattern in the monitor pattern does not necessarily have the same shape as the unit pattern in the transfer pattern (see FIG. 4B).

  Thus, in the photomask manufacturing method of the present invention, the transfer pattern includes a repetitive portion where the unit pattern is repeated, and the monitor pattern includes the unit pattern included in the transfer pattern and the dimension in the X direction or the Y direction. It is preferable to include a repeating portion in which a unit pattern having a portion equal to is repeated. In the photomask manufacturing method of the present invention, the transfer pattern includes a repeated portion where the unit pattern is repeated, and the monitor pattern includes a repeated portion where the same unit pattern as that included in the transfer pattern is repeated. It is preferable.

  However, it is preferable that the etching environment approximates the transfer pattern and the monitor pattern. Therefore, the transfer pattern and the monitor pattern have a difference (A−B (%)) of 20 when the pattern aperture ratio in a square area of 1 mm square is A (%) and B (%), respectively. (%) Or less is desirable, more preferably 10 (%) or less. Here, the aperture ratio is the ratio of the area from which the optical film is removed in the pattern unit area.

  The number of repeating unit patterns included in the monitor pattern is not particularly limited as long as it can be arranged in the area of the portion where the monitor pattern is formed. Preferably, in one monitor pattern, about 3 to 1000 unit patterns, more preferably 10 to 500 units are arranged in the X and Y directions. The area of the portion where the monitor pattern is formed may be any as long as it provides appropriate accuracy and convenience for dimensional measurement described later. This monitor pattern is not used for driving the display device to be obtained.

  FIG. 3B is an enlarged schematic view of the transfer pattern exemplified in this embodiment. In FIG. 3B, pixel patterns P11, P12,... Having the same shape are regularly arranged in the X direction and the Y direction. In the example of FIG. 3B, for example, one pixel pattern P11 can be a unit pattern, and P11, P12, and the like can be unit pattern repeat patterns. For example, a repetitive pattern including two pixel patterns (P11, P12, P21, and P21) in the X direction and the Y direction can be used as the unit pattern. The dimensions of the unit patterns (that is, the pattern repetition period) are about 10 to 300 μm in the X and Y directions, respectively, and a large number are arranged in the X and Y directions. Hereinafter, this aspect will be described on the assumption that one pixel pattern (P11, P12, etc.) is a unit pattern.

  The transfer pattern is provided with a guarantee unit. This is an arbitrary part included in the transfer pattern and can be a part for which high CD accuracy is required. In FIG. 3B, the X-CD guarantee unit is defined as the width in the X direction of the unit pattern P22, and the Y-CD guarantee unit is defined as the width in the Y direction.

  FIG. 3C shows an enlarged schematic view of the monitor pattern M used when the transfer pattern is used. Among these, the unit patterns (M11, M12...) Having the same shape as the unit patterns (P11, P12...) Included in the transfer pattern have the same pitch as the unit patterns included in the transfer pattern. Arranged. An X-CD measurement unit is provided as a width in the X direction of the unit pattern M22, and a Y-CD measurement unit is provided as a width in the Y direction. Further, the dimensions of the X-CD guarantee section and the Y-CD guarantee section of P22 are the same as the dimensions of the X-CD measurement section and the Y-CD measurement section of M22, respectively.

  In this embodiment, after the first etching of the optical film, the measurement of the X-CD measurement unit of M22 and the measurement of the Y-CD measurement unit are performed to accurately grasp the degree of etching progress of the optical film in the P22 part. The etching time applied to the subsequent second etching can be determined.

  By the way, in the above example, P22 and M22 are drawn under the same drawing conditions, and therefore the CD measurement unit and the CD guarantee unit are CDs under the same drawing conditions. This point will be described below.

  FIG. 7 shows the movement of the laser beam emitted from the drawing head in the laser drawing apparatus used in this embodiment. This drawing apparatus repeats the operation of scanning the laser beam in the Y direction for a predetermined scan length and then sending the laser beam in the X direction for a predetermined feed length. When the drawing of a predetermined area (one stripe) is completed by repeating this operation, the drawing head or stage moves to draw the next stripe. Of course, these movements can be performed as a combination of relative movements of the drawing head or stage, along with movements of a predetermined amplitude of the laser beam.

  The seam portion (the boundary portion with the adjacent stripe) in FIG. 7 may be overlapped or touched by scanning (laser beam irradiation).

  For example, in the case of single-beam drawing with a beam diameter of A (μm), the laser feed length in the X direction is also A (μm). On the other hand, in the multi-beam method in which a plurality of beams are scanned simultaneously, the beam feed length in the X direction is an integral multiple of the beam diameter.

  Note that the present invention can be applied to both the single beam system and the multi-beam system, but the effect of the invention is remarkable particularly in the case of the multi-beam system.

  FIG. 8 shows the movement of the laser beam emitted from the drawing head of the laser drawing apparatus.

  FIG. 9 shows a method of controlling the line width (CD) in the Y direction by the laser beam emitted from the drawing head of the laser drawing apparatus. During one scan in the Y direction, the CD is controlled by the timing of turning on / off the laser beam. That is, the laser beam is turned on / off in units of a grid G (for example, G = 0.005 μm), which is the minimum unit defined in the drawing apparatus, and the edge of the pattern is defined. However, the energy irradiated from the laser beam is not always constant during one scan. Rather, even within one scan in the Y direction, that is, the laser beam swing width (beam scan length), there are many cases in which there is a disturbance inherent in the apparatus and the amount of light is not uniform.

  On the other hand, as shown in FIG. 10, the CD (line width) of the pattern in the X direction is determined by the irradiation intensity of the laser beam (beam diameter A μm) emitted from the drawing head of the laser drawing apparatus. Here, light of a light amount by a plurality of beams obtained by combining the light of the individual beams is irradiated. However, since the plurality of beams are arranged at a constant distance (in the X direction) and the relative position cannot be moved, when drawing the edge of the pattern, the beam power is set so that the required line width is obtained. adjust. For example, in FIG. 10B, if a width of A μm is drawn by an A μm beam, a beam intensity of 100% may be set for this beam. As shown in FIG. 10C, when drawing a line width of 1.3 A μm, the power (laser beam intensity) of 100% (indicated by a white circle) and the power of 30% (indicated by a gray circle) And draw. By doing so, a pattern having a line width other than an integral multiple of the beam diameter can be drawn. Thus, CD control in the X direction is performed by beam power control. The beam power control can be adjusted in stages. For example, in the case of a beam having a beam diameter of 0.25 μm, the beam intensity can be changed in 50 steps (in increments of 0.005 μm).

  As described above, generally, in a drawing apparatus, CD definition in the X direction and CD definition in the Y direction are performed by the above-described mechanisms. If there is no non-uniformity in beam intensity in X direction feeding, individual beam differences (in the case of the multi-beam method), and there is no fluctuation in beam intensity in each scan in the Y direction, theoretically the ON / OFF of the above The designed CD is reproduced at any position by the control (Y direction) and the beam intensity arrangement combination (X direction). However, in reality, the energy irradiated during one scan also has variations inherent to the apparatus. Therefore, it is inevitable that the shape of the resist pattern to be formed changes due to these variation factors. Furthermore, in the multi-beam method in which scanning is performed simultaneously with a plurality of beams, the drawing efficiency is increased, but the irradiation amount varies due to individual differences among the individual beams.

  In consideration of the above, when measuring the dimensions of the monitor pattern of the present invention, the drawing conditions applied in the formation of the resist pattern serving as an etching mask for the monitor pattern should be matched with the transfer pattern. It can be a truly reliable dimension measurement. That is, it is effective to apply the same drawing conditions as those applied to the transfer pattern to at least one of the monitor pattern in the X direction and the Y direction, preferably both. The drawing conditions are preferably the beam arrangement of an energy beam such as a laser beam used for drawing in the X direction and the scan position of the energy beam in the Y direction. Here, the scan position refers to a portion (position) devoted to drawing within one scan cycle.

  The beam arrangement is an arrangement of laser beam intensities. In addition, in the case of applying the multi-beam method, in addition to this, after identifying individual beams, the combination of each beam and the arrangement of the respective beam intensities are provided.

  As an example, in the transfer pattern shown in FIG. 3B, a constant feed length in the X direction (for single beam drawing, the feed length is equal to the laser beam diameter, and for multi-beam drawing, an integral multiple of the beam diameter). .)), While a laser beam is being sent, a scan with a constant scan length (for two pixels) is performed in the Y direction, and this is repeated. The white circle indicates 100% laser beam intensity, the black circle indicates 0% (OFF), and the gray circle indicates the intermediate intensity.

  Here, in the X direction, there are 21 laser beam diameter arrays (in FIG. 3B, 100%, 0%, 0%, etc. as beam arrays corresponding to white circles, black circles, black circles... From the bottom). Is the drawing repetition cycle, which corresponds to two pixels P11 and P21 (two unit patterns in the X direction). Also in drawing after P31, two pixels in the X direction are drawn by the beam arrangement of the 21 laser beams.

  Here, the unit pattern P22 provided with the guarantee unit is drawn by the upper half of the beam arrangement of the 21 laser beams.

  On the other hand, in the Y direction, the drawing length of the drawing apparatus is two pixels, and this drawing scan is repeated. Therefore, in the example shown in FIG. 3, the drawing repetition cycle in the Y direction is the scan length. Here, P22 is drawn by the second half (right side) scan position of this one scan length.

  In the monitor pattern shown in FIG. 3C, unit patterns M11 and M21 having the same size as P11 and P21 are arranged in the same manner as the transfer pattern shown in FIG. The monitor pattern is also drawn as the same X-direction beam array as described above (that is, from the bottom, a combination of 21 white circles, black circles, black circles... Gray circles from the bottom).

  Therefore, for the measurement parts (X-CD measurement part, Y-CD measurement part) to be measured in the dimension measurement process, drawing of 21 laser beams is performed as in the case of the transfer pattern shown in FIG. It can be seen that an X-CD measurement unit with the upper half of the repeat unit and a Y-CD measurement unit with the second half scan position in the Y direction may be used. As understood from FIG. 3C, M22 provided with the measurement unit is drawn by the upper half of the array of 21 beams in the X direction and is the latter half of one scan length in the Y direction. Drawing is based on the scan position on the right side. Thus, it is effective for precise CD management to apply the same drawing conditions as those applied to the transfer pattern to at least one of the X direction and Y direction of the monitor pattern, preferably both. In addition, it is effective for precise CD management that the drawing conditions include at least one selected from the X-direction beam arrangement and the Y-direction scan position of the energy beam used for drawing.

  By taking into account the drawing mechanism and determining the object of dimension measurement, very precise CD management becomes possible. That is, as described above, when at least a part of the transfer pattern is a CD guarantee part, the CD measurement part of the monitor pattern has the same dimensions as the CD guarantee part of the transfer pattern and the CD guarantee of the transfer pattern. By determining the CD measurement unit that is the object of dimension measurement so that the drawing is performed under the same drawing conditions as those of the unit, extremely precise CD management can be performed.

  When the multi-beam method is applied, not only the beam intensity array but also the individual beams are identified (for example, beam No. 1, No. 2...) It is preferred to consider the sequence and its individual strength simultaneously. In other words, the arrangement of the used beams and the combination of the beam intensities are made completely the same in the transfer pattern guarantee section and the measurement section in the monitor pattern. As a result, the drawing state (drawing condition) in the transfer pattern, including slight individual differences of individual laser beams, is reflected in the monitor pattern, and the reliability of dimension measurement in the subsequent process can be improved.

  As described above, in the photomask manufacturing method of the present invention, the effect of the present invention is obtained when there is a drawing repetition period (beam arrangement) in the X direction in which a predetermined drawing condition is repeated in the X direction in the drawing process. Is remarkable. The beam arrangement is repeated every drawing repetition period in the X direction.

  In the example described with reference to FIG. 3 described above, the drawing repetition period (beam array) in the X direction in the drawing process and the pitch (repetition period) in the X direction of the unit pattern were 2: 1. In other words, in the example shown in FIG. 3, the drawing repetition period in the X direction (for 21 beams) is the length of two unit patterns in the X direction (unit patterns in the case of the monitor pattern: P11 and P21 (M11 and M21 in the case of the monitor pattern)). In the X direction). However, the present invention is not limited to this, and the least common multiple of the drawing repetition period in the X direction and the pitch in the X direction of the unit pattern is an integer of 20 or less, more preferably 15 or less, and even more preferably 10 or less. In some cases, selection of a plurality of CD assurance units (or CD measurement units) is easy and advantageous.

  In the above example, the drawing repetition period (scan length) in the Y direction in the drawing process and the pitch (repetition period) in the Y direction of the unit pattern were 2: 1. That is, in the example shown in FIG. 3, the length of the Y-direction drawing repetition period (scan length) is the length of two unit patterns in the Y direction (P11 and P12 (M11 and M12 in the case of a monitor pattern)). This corresponds to the pitch of the unit pattern in the Y direction). However, the present invention is not limited to this. When the least common multiple of the Y-direction drawing repetition period and the unit pattern Y-direction pitch is an integer of 20 or less, more preferably 15 or less, and even more preferably 10 or less. This makes it easy to select a plurality of CD assurance units (or CD measurement units), which is advantageous.

  In this way, the pattern data can be processed in order to set the range of the least common multiple. For example, the pattern data is enlarged or reduced in advance in the X or Y direction, and the unit pattern dimension is adjusted so as to have the drawing repetition period in the X or Y direction and the least common multiple that is an integer of 20 or less. In this case, it is possible to correct the reduction or enlargement to return to the original scale.

  In the present invention, the Y-direction scan length can be set to a width smaller than the maximum scan length of the drawing apparatus. By doing so, the least common multiple of the above range may be obtained.

  The transfer pattern (and the shape of the monitor pattern corresponding thereto) is not limited to the shape shown in FIG. 3, but is designed according to the use of the photomask to be manufactured.

  The transfer pattern shown in FIG. 4 is basically the same as that shown in FIG. 3, but since the CD guarantee part of the transfer pattern is only the Y-CD guarantee part, the monitor pattern does not require measurement by the X-CD measurement part. . Accordingly, the shape of the monitor pattern shown in FIG. 4 is a line & space pattern. However, as shown in FIG. 4, the edges of the optical film pattern to be measured correspond to each other, and the design dimensions of the Y-CD assurance unit and the Y-CD measurement unit are equal.

  FIG. 5 illustrates a pattern having a complicated shape such as an S / D layer of a TFT transistor. In the example shown in FIG. 5, since there are two Y-CD guarantee portions (one of which is the channel portion) of the transfer pattern, the monitor pattern Y-CD measurement portion also has two locations corresponding thereto. Is provided. In this example, the drawing repetition period in the X direction and the Y direction coincides with the pitch of the unit pattern in the X direction and the Y direction (1: 1). The unit pattern of the monitor pattern has the same shape as the unit pattern of the transfer pattern.

  In the example shown in FIG. 5, the X-CD guarantee part of the transfer pattern is a space part (translucent part), and the Y-CD guarantee part is a line part (light-shielding part) and a space part (translucent part). In the monitor pattern, corresponding portions having the same width are used as X-CD measurement units and Y-CD measurement units as measurement objects for dimension measurement.

  FIG. 6 is a diagram in which OPC (optical proximity correction) is arranged at each corner of a square pattern, but the relationship between the drawing laser beam arrangement, the guarantee unit, and the measurement unit is the same as the example in FIG. .

  It is shown that the pattern design in the guarantee part and the measurement part does not necessarily match completely, and the position of the optical film edge used for the CD measurement only needs to correspond in both. That is, there is a light-shielding pattern of a predetermined design in the guarantee part, and the measurement part has a missing part or an additional part with respect to the pattern shape (FIG. 6 is an example of this), or the light-shielding pattern in the measurement part. Even if the pattern is separated into a plurality of parts, if there is a corresponding one at the position of the edge of the optical film used for CD measurement, “there is a CD measurement part having the same dimensions as the CD guarantee part” Shall.

  Although the above description has been given of the case where a laser beam is used for drawing, the present invention can be similarly applied to the case where another energy beam such as an electron beam is used.

  In the above description, the case where one transfer pattern is formed on the transparent substrate has been described, but this is preferably applied to a so-called binary mask. However, the present invention is not limited to this. For example, when multiple layers of patterns are formed on a transparent substrate by drawing and etching, the present invention can be applied to any one of the layers, and the present invention can be applied to all layers. You can also.

  For example, by forming a light shielding film and a semi-transparent film that transmits a part of the exposure light on a transparent substrate, and patterning each, a transfer pattern including the light shielding part, the translucent part, and the semi-transparent part Thus, when manufacturing a multi-tone photomask, the manufacturing method of the present invention can be applied.

  Alternatively, when manufacturing a phase shift mask that forms a transfer pattern by forming a phase shift film that inverts the phase of exposure light on the transparent substrate and a light shielding film in addition to this, and patterning each of them. It is also possible to apply the manufacturing method of the present invention.

  The use of the photomask by the manufacturing method of the present invention is not particularly limited. For example, the photomask transfer pattern manufactured by the photomask manufacturing method of the present invention can be a pattern for manufacturing a display device such as a liquid crystal display device (LCD) and an EL display device.

  The present invention includes a method for manufacturing a display device by using a photomask according to the above manufacturing method and transferring a transfer pattern onto a transfer target by an exposure apparatus. That is, the manufacturing method of the display device of the present invention includes a step of preparing a photomask according to the above manufacturing method, and a step of transferring a transfer pattern of the photomask onto a transfer target using an exposure device. Have. According to the method for manufacturing a display device of the present invention, it is possible to manufacture a display device in which a transfer pattern with high dimensional accuracy is transferred to a transfer target.

  Here, it is preferable that the exposure apparatus used is a projection exposure apparatus (for example, the numerical aperture NA of the optical system is 0.08 to 0.9) that is known for LCD or FPD. As the exposure light source, light having a broad wavelength including i-line, h-line, and g-line can be used. It is of course possible to use a proximity exposure apparatus that uses the same light source.

  Moreover, this invention is a photomask provided with the pattern for transcription | transfer obtained by patterning an optical film on a transparent substrate, and several monitor patterns. The plurality of monitor patterns are formed outside the transfer pattern area. In the photomask of the present invention, when at least a part of the transfer pattern is a CD guarantee part, the monitor pattern has the same dimensions as the CD guarantee part and is formed under the same drawing conditions as the CD guarantee part. Have The drawing condition is at least one of the X-direction beam arrangement or the Y-direction scan position of the energy beam used for drawing the transfer pattern. The beam arrangement in the X direction and the scan position in the Y direction are as described above. The photomask of the present invention has a transfer pattern with high dimensional accuracy.

DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Optical film 2a Optical film pattern (transfer pattern)
2b Optical film pattern (monitor pattern)
3 Resist film 3a Resist pattern (resist pattern of the portion where the transfer pattern is formed)
3b Resist pattern (resist pattern where the monitor pattern is formed)
6 Laser beam

Claims (12)

A method for producing a photomask comprising a transfer pattern obtained by patterning an optical film on a transparent substrate,
Preparing a photomask substrate having the optical film and a resist film on the transparent substrate;
A drawing process for drawing on the resist film based on predetermined pattern data using a drawing apparatus;
A resist pattern forming step of forming a resist pattern by developing the resist film;
An optical film patterning step of forming an optical film pattern by etching the optical film using the resist pattern as a mask,
The drawing step includes the transfer pattern data for forming the transfer pattern to be obtained and the monitor pattern data for forming a monitor pattern for measuring dimensions outside the transfer pattern area. Draw using pattern data,
The optical film patterning step includes
A first etching that etches the optical film for a predetermined time; and
Measuring the dimensions of the monitor pattern;
A second etching that performs additional etching on the optical film based on the dimensions of the monitor pattern obtained by the dimension measurement;
Including
The monitor pattern includes a CD measurement unit having the same dimensions as the CD guarantee unit and drawn under the same drawing conditions as the CD guarantee unit when at least a part of the transfer pattern is a CD guarantee unit,
The same drawing conditions, the energy beam used for drawing, wherein it X direction of the beam array are identical, and it Y direction scan position of the energy beam is the same, at least one selected from ,
The method for manufacturing a photomask, wherein the dimension measurement is performed on the CD measurement unit.   The method of manufacturing a photomask according to claim 1, wherein the first etching and the second etching are wet etching.   3. The method of manufacturing a photomask according to claim 1, wherein the resist film in a portion where the monitor pattern is formed is partially removed in the dimension measurement.   4. The monitor pattern according to claim 1, wherein a plurality of the monitor patterns are arranged outside the area of the transfer pattern on the transparent substrate, and each of the plurality of monitor patterns has the CD measurement unit. 2. A method for producing a photomask according to claim 1. The transfer pattern includes a repeating portion where a unit pattern is repeated,
2. The monitor pattern according to claim 1, wherein the monitor pattern includes a repeated portion in which the unit pattern included in the transfer pattern and a unit pattern having a portion having the same dimension in the X direction or the Y direction are repeated. The manufacturing method of the photomask of any one of -4. The transfer pattern includes a repeating portion where a unit pattern is repeated,
6. The photomask manufacturing method according to claim 1, wherein the monitor pattern includes a repeated portion in which the same unit pattern as the unit pattern included in the transfer pattern is repeated. Method.   The drawing step has a drawing repetition cycle in the X direction in which the predetermined drawing conditions are repeated in the X direction, and the beam arrangement is repeated for each drawing repetition cycle in the X direction. The manufacturing method of the photomask of any one of Claims 1-6.   The drawing step has a drawing repetition cycle in the Y direction in which the predetermined drawing conditions are repeated in the Y direction, and the scan position is repeated for each drawing repetition cycle in the Y direction. The manufacturing method of the photomask of any one of Claims 1-7.   The method for manufacturing a photomask according to claim 1, wherein the transfer pattern is a pattern for manufacturing a display device.   The photomask manufacturing method according to claim 1, wherein a laser drawing apparatus is used for the drawing process. A display device manufacturing photomask comprising a transfer pattern obtained by patterning an optical film on a transparent substrate and a plurality of monitor patterns,
The monitor pattern is provided outside the transfer pattern area,
When at least a part of the transfer pattern is a CD guarantee part, the monitor pattern has a CD measurement part having the same dimensions as the CD guarantee part and formed under the same drawing conditions as the CD guarantee part. ,
Wherein the same drawing conditions, the energy beam used for drawing of the transfer pattern, X direction of the beam array is the same, or that the Y-direction scanning position of said energy beam is the same, of at least A photomask for manufacturing a display device , characterized by being one. A step of preparing a photomask by the manufacturing method according to any one of claims 1 to 10,
And a step of transferring the transfer pattern of the photomask onto a transfer target using an exposure apparatus.