KR100712187B1 - An apparatus for removing the edge bead of the blank mask and removing method thereof - Google Patents

Abstract

An edge bead removal device of the disclosed blank mask includes: an outer chuck spaced apart from the top of the blank mask; An inner chuck spaced apart from each other so as to form a space at a lower portion of the outer chuck, and through which the solvent for removing edge beads passes; A gas supply unit for injecting an inert gas through a nozzle formed at the center of the blank mask to prevent the edge bead removal solvent from penetrating into the main pattern of the blank mask; And a protective film interposed between the blank mask and the inner chuck to block the inert gas flowing through the gas supply unit from being directly contacted with the blank mask. According to the edge bead removal device of the blank mask, it is possible to effectively remove the edge beads formed on the side and corner portions of the blank mask, and significantly reduce the fringes and stains that may occur in the main pattern.

Blank Mask, Edge Bead, Melt, Protective Film

Description

An apparatus for removing the edge bead of the blank mask and removing method

1 is a blank mask showing a state in which the edge bead is removed by a conventional method,

2 is a view showing a position where the spacer pin is attached to the conventional blank mask,

3 is a view showing a state after performing an edge bead removal process on the blank mask shown in FIG.

4 illustrates an edge bead removal device of a blank mask according to an embodiment of the present invention;

5 is a view showing a position where the protective film shown in FIG. 4 is installed;

6 is a view showing a position where the spacer pin is in contact with the blank mask according to an embodiment of the present invention,

FIG. 7 illustrates a state in which edge beads are removed from the blank mask shown in FIG. 6;

FIG. 8 is a view illustrating a state in which edge beads are formed by coating a photomask on a blank mask in a spin method.

9 is a view showing a state in which the edge bead is removed using a solvent for removing the edge bead according to an embodiment of the present invention,

10 illustrates an edge bead removal process according to another embodiment of the present invention;

FIG. 11 is a view showing a blank mask from which edge beads are removed by an edge bead removal device and a removal method according to the present invention. FIG.

<Description of the symbols for the main parts of the drawings>

100 ... Edge bead remover 110 ... Nozzle

120 ... external chuck 130 ... internal chuck

140 ... Blank Mask 150 ... Shield

The present invention relates to an edge bead removal device and a method of removing a blank mask, and more particularly, to an edge bead removal device of a blank mask for effectively removing edge beads generated on side and corner edge portions of a blank mask after photoresist coating. And a method of removal.

In general, a blank mask is a raw material of a photomask used in semiconductor and LCD processes, and a pattern is drawn on the blank mask to manufacture photomasks for semiconductors and LCDs.

On the other hand, such a blank mask has a problem that the photoresist is coated on the surface by spin coating, but the photoresist is not uniformly coated on the blank mask, but is thickly coated at the side portion or the corner portion to form edge beads. do.

Typically, the blank mask is loaded or transported in a storage case or a storage cassette at the time of loading or production, and these edge beads are separated by the handling process of the storage cassette or the blank mask to generate dust and increase defects.

Thus, a process for removing such edge beads is inevitably involved.

The edge beads formed on the outer portion of the blank mask are removed by a photoresist removal solvent, and in particular, the type, supply amount and supply time of the photoresist solvent supplied are determined according to the dissolution rate of the solvent.

Generally, the photoresist edge bead removal solvent is composed of a volatile composition. Therefore, when the photoresist solvent is supplied during a long time of the edge bead removal process, the centrifugal force acts in the direction of the edge bead removal region in the main pattern region. There is a possibility that the liquid and vapor of the solvent can penetrate into the main pattern region. In addition, as the photoresist dissolving agent is supplied during the rotation, an irregular air flow due to the flow of the irregular feed and the rotation is formed, resulting in uneven edge bead removal. These phenomena eventually lead to an increase in reject rate during the edge bead removal process.

In addition, the conventional method is generally supplied with a solvent for removing photoresist edge beads while rotating at a rotational speed of 200 RPM or more, while a uniform supply of the solvent for removing photoresist edge beads is induced when rotating at a rotational speed of 200 RPM or more. , The dissolving agent for removing the photoresist edge beads due to the centrifugal force generated at a rotation speed of 200 RPM or more is concentrated at the edge corners of the blank mask.

1 is a blank mask illustrating a state in which edge beads are removed by a conventional method.

Referring to FIG. 1, a blank mask 10 having edge beads removed by a conventional method may include a photoresist-coated region 1 and a chrome film region 2 having edge beads removed from side edges and corner edges. It is divided into), which shows the shape of the edge bead removed excessively.

In the blank mask 10, the effective pattern area is reduced by that in the photomask fabrication process, and thus, it is difficult to insert an auxiliary pattern such as a barcode.

In addition, conventionally, a gap retaining pin for maintaining a gap between the blank mask and the internal chuck is generally formed at the side edge portion of the blank mask.

2 is a view showing a position where a spacer pin is attached to a conventional blank mask, Figure 3 is a view showing a state after performing the edge bead removal process to the blank mask shown in FIG.

First, referring to FIG. 2, a gap retaining pin (not shown) for maintaining a gap between the blank mask 10 and the inner chuck (not shown) may be a side edge portion 3 of the outer side 2 of the blank mask 10. Located in On the other hand, in the corner edge portion 4 of the substrate is exposed a transparent substrate that is not coated with a photoresist.

Meanwhile, referring to FIG. 3, when the edge bead removal process is performed while the gap holding pin is attached to the side edge part 3, the side edge part 3 ′ in contact with the gap holding pin is a solvent for removing edge beads. Does not penetrate and the photoresist remains.

In this state, when chrome etching is performed in the post process, a pin mark of the side edge portion 3 ′ in contact with the spacer pin remains in the edge bead region of the blank mask 10.

Therefore, in order to remove the pin marks, the substrate must be rotated by 90 ° after one edge bead removal process is inevitable, and the pins are repositioned at the portions removed in the previous edge bead removal process and the second edge bead removal process is required.

Therefore, the process time is increased by repeating the same process, and the probability of defects is increased due to the repetition of the same process.

The present invention has been made to solve the above problems, and effectively removes the edge beads formed on the side and corner portions of the blank mask during photoresist coating, and significantly reduces fringes and stains that may occur in the main pattern. In order to provide an edge bead removal device of a blank mask, pin marks are not generated during an edge bead removal process.

It is still another object of the present invention to provide a method for removing edge beads of a blank mask which can effectively remove edge beads by introducing a dissolving agent for edge bead removal in consideration of dissolution characteristics.

Other objects and advantages of the invention will be described below and will be appreciated by the embodiments of the invention. Furthermore, the objects and advantages of the present invention can be realized by means and combinations indicated in the claims.

 Edge bead removal device of the blank mask according to an aspect of the present invention, the outer chuck spaced apart on the upper portion of the blank mask; An inner chuck spaced apart to form a space under the outer chuck, and through which the dissolving agent for removing the edge beads passes; A gas supply unit for injecting an inert gas through a nozzle formed at the center of the blank mask to prevent the edge bead removal solvent from penetrating into the main pattern of the blank mask; And a protective film interposed between the blank mask and the inner chuck to block an inert gas flowing through the gas supply unit from being directly contacted with the blank mask.

Here, the protective film preferably has a distance G1 in the vertical direction from the blank mask of 1 to 2.5 mm.

In addition, the protective film preferably has a distance G2 in the vertical direction from the inner chuck of 0.5 to 2 mm.

In addition, the protective film is preferably a distance (d) of 10 to 30 mm in the horizontal direction and the inner chuck.

The inner chuck may further include a gap retaining pin for maintaining a predetermined gap with the blank mask, and the gap retaining pin is attached to each corner of the inner chuck.

In addition, the inner chuck preferably has a thickness of 0.5 to 3.0 mm.

Edge bead removal method of the blank mask according to another aspect of the present invention, by inserting a solvent to dissolve the edge bead into the space formed between the inner chuck and the outer chuck rotating the blank mask on the rotating disc to remove the edge bead, The main pattern of the blank mask is protected by supplying an inert gas.

Here, the rotational speed of the rotating disc is preferably 100 to 200 RPM.

In addition, the inlet pressure of the inert gas is preferably 0.01 to 0.05 MPa.

The solubilizing agent may be acetone, propylene glycol monomethyl ether (PGME), toluene, butyl acetate, propylene glycol monomethyl ether acetate (PGMA), isopropyl alcohol (IPA), methyl isoamyl ketone (MAK), ethyl lectate ( EL), diethylene glycol dimethyl ether (DIGLYME) and tetra methyl ammonium hydroxide (TMAH) are preferably used.

In addition, the solubilizing agent is a first dissolving agent selected from the group consisting of acetone, EL and DIGLYME; Secondary solubilizers selected from the group consisting of MAK, butyl acetate, PGMA and TMAH; And it is preferable to remove the edge bead sequentially supplying a third solubilizer selected from the group consisting of IPA, PGME and toluene.

In addition, when the dissolving agent is supplied, the dissolving agent selected from the first dissolving agent is supplied in the range of 1 to 5 seconds, the dissolving agent selected from the second dissolving agent is supplied in the range of 1 to 3 seconds, and the dissolving agent selected from the third dissolving agent is 5 to 10 It is preferred to include a drying step of supplying in the second range, and drying the solubilizer for 10 to 100 seconds after each solubilizer is supplied.

In addition, the drying step is preferably dried by rotating at a rotational speed equal to or less than the rotational speed of the rotating disc.

It is also desirable to remove edge beads formed on the back side of the blank mask using one or more of these solvents.

The terms or words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

4 is a view showing an edge bead removal device of a blank mask according to an embodiment of the present invention, Figure 5 is a view showing a position in which the protective film shown in Figure 4 is installed, Figure 6 according to an embodiment of the present invention FIG. 7 is a view showing a position where the spacer pin is in contact with the blank mask, and FIG. 7 is a view showing an edge bead removed from the blank mask shown in FIG. 6.

First, referring to FIG. 4, the edge bead removing device 100 of the blank mask according to an embodiment of the present invention includes a rotating disc (not shown), an outer chuck 120, an inner chuck 130, and a gas supply unit (not shown). C) and a protective film 150.

The rotation disc is rotated by seating the blank mask 140 on the upper surface, the outer chuck 120 is located at a predetermined interval spaced above the blank mask 140.

On the other hand, as an example of the present invention, a rotating disc may be used to rotate the blank mask, but is not necessarily limited thereto, and the same effect may be achieved by the outer chuck 120 and the inner chuck 130 which will be described later without using the rotating disc. Can be represented.

In addition, an inner chuck 130 having a space portion 131 spaced apart from the outer chuck 120 by a predetermined interval is provided, and a solvent for removing edge beads is passed through the space portion 131.

At this time, the thickness of the inner chuck 130 is preferably 0.5 ~ 3.0 mm.

When the edge bead removal solvent dissolves the side edges and corner edges of the blank mask 140, the width of the edge beads is determined according to the thickness of the inner chuck 130. This is because a capillary phenomenon occurs between 130 and the blank mask 140.

Therefore, the thickness of the inner chuck 130 is an important factor in which the solvent can be sucked by the capillary phenomenon, and when the thickness of the inner chuck 130 is less than 0.5 mm, the solvent and the side of the blank mask 140 It is difficult to remove the edge beads formed at the corner edges, and when the thickness exceeds 3.0 mm, a large amount of solvent may be sucked in and the edge bead removal width may be too wide.

Hereinafter, the protective film and the gas supply unit according to an embodiment of the present invention will be described in detail.

Edge bead removal solvent is introduced into the side and corner edges of the blank mask 140 through the space portion 131, the solvent is introduced in the gas phase of the blank mask 140 because the solvent is usually highly volatile Can flow into the main pattern of the central portion.

In order to prevent the gaseous solvent from penetrating into the main pattern of the blank mask 140, an inert gas is supplied through the gas supply unit.

In the gas supply unit, an inert gas is injected from the center of the blank mask 140 to the periphery through the nozzle 110 formed at the center of the blank mask 140, and thus, the forced air flow is formed in the upper part of the blank mask 140. Will be formed.

However, when a strong air flow is formed to prevent the gaseous solvent from penetrating into the main pattern of the blank mask 140, it is directly rubbed against the main pattern region of the blank mask 140 which is not soft baked after the photoresist coating. Therefore, unlike the periphery, the same state as that of forced drying is formed, so that fringe occurs. In addition, when a strong air flow is formed, even if a filter is installed in the gas supply line, dust and foreign matters are not properly filtered and directly attached to the main pattern region.

As the forced air flow is formed as described above, the protective film 150 is provided to prevent the influence of the main pattern of the blank mask 140.

The passivation layer 150 is interposed between the blank mask 140 and the inner chuck 130 to block the inert gas flowing through the gas supply unit from being directly contacted with the blank mask 140.

As an example of the present invention, the protective film 150 has a distance G1 in the vertical direction from the blank mask of 1 to 2.5 mm, and a distance G2 in the vertical direction from the inner chuck 130. 2 mm, the distance (d) in the horizontal direction and the inner chuck 130 is preferably 10 to 30 mm (see Fig. 5).

When the gap G1 between the protective film 150 and the blank mask in the vertical direction is less than 1 mm, an edge bead removal process is performed after the photoresist coating and before subsequent baking, thereby volatilizing the solvent generated on the photorest coated surface. Vortex may be generated by the vapor and rubbed back onto the coated surface, causing changes in sensitivity and other contamination.

If the gap G1 exceeds 2,5 mm, it is too close to the internal chuck, leading to abnormal air flow of the gas flowing from the gas supply unit, thereby preventing the effective edge bead removal process.

In addition, the edge bead removal width is uniform depending on the distance G2 in the vertical direction between the passivation layer 150 and the inner chuck 130 and the separation distance d in the horizontal direction of the inner chuck 130. The sex is determined.

The horizontal separation distance d between the passivation layer 150 and the inner chuck 130 serves to induce the inlet gas to be uniformly pressurized at each edge to uniformly remove the edge beads by the solvent.

In addition, the vertical gap G2 between the passivation layer 150 and the inner chuck 130 is an edge corner through effective airflow and induction to each edge corner portion even in the upper portion of the rotating disk on which the inert gas flowing from the gas supply portion rotates. The supply of dissolving agent to the part is stabilized so that the edge beads can be removed with the same width as the edge part.

On the other hand, the supply of inert gas as an example of the present invention is used in the range of 0.01 to 0.05 MPa. At this time, when the supply pressure of the inert gas is less than 0.01MPa, the gas supply pressure is weak so that the solvent introduced due to the low rotational speed flows into the blank mask main pattern region.

On the other hand, if it exceeds 0.05 MPa, the pressing force is too large to cause the problem that the solvent to remove the edge bead flows down immediately without passing through the edge bead occurs.

And, the rotational speed of the rotating disc as an example of the present invention preferably maintains a low speed of 100 to 200 RPM.

Because, in general, a solvent for removing photoresist edge beads is supplied while the rotating disc rotates at a rotational speed of 200 RPM or more, and the solvent for removing photoresist edge beads flowing down the surface of the inner chuck 130 is 200 RPM or more. The speed of rotation increases the amount of flow to the four edge corners.

Therefore, when the edge bead is removed under the above conditions, the beads present in the four edge corner portions are more dissolved than the edge side portions, thereby making it difficult to remove the edge beads having a uniform width. In the photomask fabrication process, the effective pattern area is reduced by that amount, and difficulty in inserting an auxiliary pattern such as a barcode is generated.

In order to solve such a problem, as an example of the present invention, an edge bead removal process adopting a low speed of 100 to 200 RPM is performed to reduce corner deflection caused by centrifugal force.

Performing the edge bead removal process at a low speed has the advantage of making the edge bead removal width uniform and extending the effective pattern portion which can be reduced at the edge corner portion.

At this time, when the rotating disk rotates at a low speed and the centrifugal force decreases, the pulling phenomenon of the photoresist edge bead removal solvent to the edge corner portion is improved, but when the edge bead is removed by supplying a highly volatile photoresist edge bead removal solvent. Therefore, a problem may occur that the liquid and vapor of the solvent are sucked from the edge portion to the main pattern region.

However, the problem that the solvent is sucked into the main pattern region can be overcome by the provision of the inert gas and the protective film 150 supplied from the gas supply unit.

In addition, as an example of the present invention, the inert gas supplied to the gas supply part is N2, but is not necessarily limited thereto, and it should be noted that an inert gas of the same kind may be used.

6 is a view showing a position where the spacer pin is in contact with the blank mask according to an embodiment of the present invention.

The spacer pin according to an embodiment of the present invention is attached to each corner of the inner chuck 130, and thus the spacer pin is contacted at the corner edge portion 144 of the blank mask 140 coated with the photoresist.

Conventionally, the spacer pins are brought into contact with the side edge portions 3 (see FIG. 2) of the blank mask, and the solvent for removing photoresist edge beads does not penetrate the side edge portions 3. A problem remains that remains in the bead removal region.

In the present invention, in order to solve such a problem, the attachment position of the spacing pin is adjusted to each corner of the inner chuck 130.

Looking at this in more detail, when the space holding pin is in contact with the corner edge portion 144 of the corner 143 of the four chromium corresponding to each corner of the inner chuck 130, the contact with the chromium-free portion As a result, even if some photoresist remains in the edge bead removal process, the photoresist removal process may be cleanly removed during the post-process to prevent the remaining of the chromium film and the adsorption of other foreign substances due to the contact between the spacer pins.

Hereinafter, an edge bead removal method of a blank mask according to another embodiment of the present invention will be described.

Edge bead removal method of the blank mask according to another embodiment of the present invention, by inserting a solvent to dissolve the edge bead into the space formed between the inner chuck and the outer chuck to rotate the blank mask on the rotating disk to remove the edge bead The main pattern of the blank mask is protected by supplying an inert gas.

At this time, the solubilizer is preferably at least one selected from the group consisting of acetone, PGME, toluene, butyl acetate, PGMA, IPA MAK, EL, DIGLYME and TMAH, the solvent is volatilized as an example of the present invention A first dissolving agent selected from the group consisting of acetone, EL and DIGLYME depending on the rate and degree of dissolution in the photoresist coated on the blank mask; Secondary solubilizers selected from the group consisting of MAK, butyl acetate, PGMA and TMAH; And three solubilizers selected from the group consisting of IPA, PGME and toluene, and the edge beads are removed by sequentially supplying the solubilizers selected from the A, B and C groups, respectively.

On the other hand, when the step of removing the edge bead according to another embodiment of the present invention step by step, the blank mask is rotated by seating on the rotating disc, the space portion formed between the inner chuck and the outer chuck spaced above the blank mask. Introducing a solvent to dissolve the edge beads; Spraying an inert gas through a nozzle formed at the center of the blank mask to prevent the solvent from penetrating into the main pattern of the blank mask; And blocking the inert gas with a protective film so that the inert gas does not directly contact the blank mask.

Hereinafter, the method of classifying the solubilizer according to the volatilization rate and the dissolution rate will be described in detail.

<Table 1> is a table | surface which classified the solvent for removing photoresist edge beads according to the volatile and the degree of melt | dissolution of a photoresist.

TABLE 1

Classification according to volatilization speed Classification by Dissolution Rate (Solubility in Novolak / Acetal Polymers) A _curve group (T <10s) Acetone, PGME, Toluene Group _for A (T <5s) Acetone, DIGLYME, MAK B _luminance group (10≤T≤15s) Butyl Acetate, PGMA, IPA A _dragon group (T <10s) Toluene, TMAH, EL, Butyl Acetate C _curve group (T> 15s) MAK, EL, DIGLYME, TMAH A _dragon group (T <10s) IPA, PGME, PGMA

<Table 1> specifically classifies the solvents according to the time when the solvent for removing photoresist edge beads is completely dried at the same temperature and humidity and the same rotation speed. The time at which the photoresist coated on the mask was completely removed was statistically classified while rotating at a constant rotational speed while continuously supplying the same flow rate of the solvent for removing photoresist edge beads on the mask.

<Table 2> is classified by combining the rate of volatilization and the degree of dissolution in photoresist when the solvent for removing photoresist edge beads is supplied to the blank mask.

TABLE 2

Classification of Solvents for Removing Photoresist Edge Beads Remarks A group Acetone, EL, DIGLYME Remove the thickest part of the edge bead B group MAK, Butyl Acetate, PGMA, TMAH Uniform edge of edge bead removed Group C IPA, PGME, Toluene Complete removal of marks remaining on the thickest part of edge beads

Each group classified into groups A, B, and C is supplied with a solvent for removing photoresist edge beads at different steps in removing edge beads of photoresist generated after the coating process, thereby performing a different role.

8 is a view illustrating a state in which edge beads are formed by coating a photomask on a blank mask in a spin method, and FIG. 9 is a state in which edge beads are removed using an edge bead removal solvent according to an embodiment of the present invention. The figure which shows.

Referring to FIGS. 8 and 9, the solvents for removing photoresist edge beads classified as shown in <Table 2> are primarily supplied with a solvent selected from group A and mainly remove edge beads formed thickest in region A. Will be performed. Therefore, it should be selected based on the solvent for removing photoresist edge bead which has excellent solubility in photoresist. In the process in which the group A is supplied, the supply of the group A photoresist edge bead removal solvent is cut off and the drying step is performed under conditions that only thick edge beads are removed without considering uniform boundaries.

In the region A ′ where the edge beads were removed, the edge beads were completely removed as shown in FIG. 9.

In the case of the second group B, the photoresist in the boundary portion (region B of FIGS. 8 and 9) from which the edge beads are removed after the first edge bead removal is removed, and the boundary portion is made uniform. Do it. In this process, the edge bead removal width can be adjusted. It can be determined by selecting a solvent for removing photoresist edge beads according to the required width, or by adjusting the supply time and pressurization conditions of the forced air generated by supplying with inert gas.

As shown in FIG. 9, the edge bead removed from the boundary portion B ′ has a shape in which the photoresist rises slightly upward to the inner surface of the inclined portion, which is caused by a dissolving agent introduced into the interior by capillary action. This is because the dissolved photoresist is finely introduced into the inside.

The solvent for removing photoresist edge beads selected from the group C supplied in the last three steps is to finally remove the dried marks and foreign substances of the photoresist and photoresist avid bead removing solvent remaining in the area A after the previous step. . This step is effective for dissolving the photoresist edge beads with low volatility and low volatility.

The dissolving agent according to an embodiment of the present invention has an edge bead removal process step of supplying a dissolving agent selected from the A, B, and C groups in the first, second, and third feeding steps, but is not necessarily limited thereto. Depending on the type, solvents for removing photoresist edge beads of A, B, and C groups may be optionally mixed and supplied, and the feeding step may be optionally reduced or added.

On the other hand, in the edge bead removal process, the rotation speed when the solvent for removing photoresist edge beads is supplied and the rotation speed of the drying process after the supply is stopped are the same.

Conventionally, after the supply of the photoresist edge bead removal solvent is supplied, it is generally changed to increase the rotation speed before it is completely dried. In this case, an abnormal air flow is formed in the blank mask, and the solvent for the photoresist edge bead removal is mainly used. Penetration or splashing occurs in the pattern area to increase the defective rate.

Therefore, in the drying step according to an example of the present invention, the drying process is performed at a rotation speed equal to or less than the rotation speed of the rotating disc at the time of supplying the solvent to prevent such a problem.

10 illustrates an edge bead removal process according to another embodiment of the present invention.

Referring to the drawings, the solubilizer selected in Group A is supplied in a range of 1 to 5 seconds, the solubilizer selected in Group B is supplied in a range of 1 to 3 seconds, the solubilizer selected in Group C is supplied in a range of 5 to 10 seconds, After the solubilizers of Group A, Group B and Group C are fed, respectively, the solvent is dried for 10 to 100 seconds, followed by final drying to remove edge beads.

At this time, each drying step is dried by rotating at the same rotational speed as the rotational speed of the rotating disc.

Meanwhile, the edge beads formed on the back side of the blank mask may be removed using one or more of the solvents classified into the above groups.

FIG. 11 is a view showing a blank mask from which edge beads are removed by an edge bead removal device and a removal method according to the present invention. FIG.

Referring to the drawings, by using the photoresist edge bead removal device and the removal method, it is possible to manufacture a blank mask 140 is removed edge bead having a high quality of the edge bead removal width is constant and no photoresist marks remaining. .

Unexplained reference numbers indicate edge bead removal regions 142 and photoresist coated regions 141.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are illustrative of the present invention, and the content of the present invention is not limited by the examples.

Comparative Example 1

The blank mask was manufactured so that an IP 3500 (made by TOK, Japan) photoresist was formed using the spin coating apparatus, and the coating thickness of 4650 mmW was formed. And the following process was performed in order to remove the edge beads which generate | occur | produced.

Without forming a protective film, edge beads were removed under optimized process conditions using MAK, a solvent of IP 3500, as a solvent for removing photoresist edge beads. At this time, nitrogen as an inert gas was pressurized to a pressure of 0.05 MPa, the rotation speed of the rotating disc was 300 RPM, the primary drying rotation speed was 450 RPM.

As a result, the edge beads were removed cleanly. Moreover, the edge bead removal width average of the side edge part showed 1.74 mm, and showed the uniform result. However, the edge corner portions were removed 0.3 to 0.5 mm wider than the average width of the side edge portions. There were also some dried marks in the photoresist and solvent in some areas where edge beads were removed.

<Example 1>

Edge beads were removed using the same blank mask as in Comparative Example 1 in the following process.

That is, a protective film made of stainless steel having a thickness of 0.5 mm, the pressure of nitrogen is 0.01 MPa, the solvent for removing the photoresist edge bead first supplies acetone, secondly MAK, and finally IPA Was fed stepwise. The rotation speed when the solvent for removing photoresist edge beads was supplied was 180 RPM, and the first drying rotation speed was the same.

As a result, the result of removing the edge bead was good, and the average width of the edge bead removal of the side edge portion was about 1.65 mm. The edge bead removal width of the edge corner portion also showed a result of 1.71 mm which was almost equal to the average. In addition, no photoresist and solvent traces occurred in the region where the edge beads were removed.

<Example 2>

As an evaluation of other photoresists, FEP 171 (manufactured by FUJI, Japan) was also evaluated for edge bead removal. FEP 171 was manufactured using a spin coating apparatus to produce a blank mask having a thickness of 3000 mm 3. In order to remove the edge beads generated at this time, an edge bead removal device equipped with the same protective film as in Example 2 was used. The pressure of nitrogen to be pressurized was 0.1 MPa, and the solvent for removing photoresist edge beads was first supplied with acetone, secondly with PGMA, and finally with PGME. The rotation speed when the solvent for removing the photoresist edge beads was supplied was 175 RPM, and the first drying rotation speed was also the same at 175 PRM. As shown in Example 1 of the IP 3500 described above, the result of the proceeding was good, and the edge bead removal width of the side edge part was about 1.59 mm. The edge bead removal width of the edge corner portion also showed a result of 1.62 mm which is almost equal to the average. Therefore, it can be seen that the result shows a very good result when proceeded by the edge bead removal device and the removal method produced by the present invention.

 <Example 3>

Table 4 shows the removal of the edge bead according to the position of the protective film shown in FIG.

TABLE 4

division G2 (unit: mm) 0.2 0.5 1.0 1.5 2.0 2.5 C S C S C S C S C S C S d in mm 5 × × ○ △ ○ △ △ ○ △ ○ × × 15 △ × ○ △ ○ ○ ○ ◎ ○ △ △ × 25 △ △ ○ ○ ◎ ○ ◎ ◎ ○ △ × × 35 × × ○ △ ○ ○ ○ △ △ △ × ×

C: corner edge of blank mask

S: side edge of blank mask

△: Normal ○: Good ◎: Very good ×: Bad

Through the results shown in Table 4, the horizontal separation distance d between the protective film and the inner chuck was 10 to 30 mm, and the edge beads had the best removal characteristics. (G2) showed good removal characteristics of the edge beads when 0.5 to 2 mm. The horizontal separation distance d between the passivation layer and the inner chuck serves to induce the inlet gas to be uniformly pressurized at each edge portion to uniformly remove edge beads by the solvent. At this time, it was confirmed that the most stable air flow is formed at 10 to 30 mm. The vertical gap (G2) between the protective film and the inner chuck ensures a stable supply of solvent to the edge corners through effective airflow and induction to each edge corner even at the top of the edge bead removal chuck where the inert gas flowing from the gas supply rotates. It serves to remove the edge bead with the same width as the edge portion. At this time, 0.5 to 2 mm showed an effective result.

As described above, the edge bead removal device and the removal method of the blank mask according to the present invention provides the following effects.

First, the edge bead removal process is performed at a low speed to prevent the solvent from being concentrated at the corner edges, thereby maintaining a uniform edge bead removal width.

Second, a protective film is provided between the blank mask and the inner chuck to prevent fringes and contamination that may be generated in the main pattern due to the inflow of inert gas.

Third, it is possible to shorten the process time and reduce the occurrence of defects because the pin can be removed in a single process by placing the spacing pin as a corner edge.

Fourth, the solvent for removing photoresist edge beads is classified in consideration of the volatilization rate and the degree of dissolution, and is sequentially supplied to remove edge beads of uniform width, and provides a good quality blank mask that does not leave foreign substances and marks. There is an advantage to this.

Fifth, since the rotational speed of the rotating disk is kept the same even after drying the solvent after dissolving the solvent, there is an advantage of preventing the phenomenon that the edge bead is unevenly removed by the abnormal airflow.

As mentioned above, although this invention was demonstrated by the limited embodiment and drawing, this invention is not limited by this, The person of ordinary skill in the art to which this invention belongs, Of course, various modifications and variations are possible within the scope of equivalent claims.

Claims (13)

An outer chuck spaced apart from the top of the blank mask; An inner chuck spaced apart to form a space under the outer chuck, and through which the dissolving agent for removing the edge beads passes; A gas supply unit for injecting an inert gas through a nozzle formed at the center of the blank mask to prevent the edge bead removal solvent from penetrating into the main pattern of the blank mask; And And a protective film interposed between the blank mask and the inner chuck to block an inert gas flowing through the gas supply unit from being directly contacted with the blank mask. Edge bead removal device of blank mask. The method of claim 1, The protective film has a distance G1 in the vertical direction from the blank mask of 1 to 2.5 mm, The distance G2 in the vertical direction and the inner chuck is 0.5 to 2 mm, Characterized in that the separation distance d in the horizontal direction with the inner chuck is 10 to 30 mm, Edge bead removal device of blank mask. The method according to claim 1 or 2, It is provided with a predetermined interval spaced below the inner chuck, further comprising a rotating disc for seating and rotating the blank mask, Edge bead removal device of blank mask. The method according to claim 1 or 2, The inner chuck is further provided with a space holding pin for maintaining a predetermined distance with the blank mask, the space holding pin is characterized in that attached to each corner of the inner chuck, Edge bead removal device of blank mask. The method according to claim 1 or 2, The inner chuck is characterized in that the thickness of 0.5 to 3.0 mm, Edge bead removal device of blank mask. A method for removing edge beads of a blank mask for removing edge beads that remain unnecessarily at edges and edge corners of a blank mask, The blank mask is rotated by seating on the rotating disc, and a dissolving agent is added to a space formed between the inner chuck and the outer chuck to remove the edge beads, and an inert gas is supplied to protect the main pattern of the blank mask. Made, How to remove edge bead of blank mask. The method of claim 6, Rotational speed of the rotating disc is characterized in that 100 to 200 RPM, How to remove edge bead of blank mask. The method according to claim 6 or 7, Inlet pressure of the inert gas is characterized in that from 0.01 to 0.05 MPa, How to remove edge bead of blank mask. The method according to claim 6 or 7, The solubilizer is characterized in that at least one selected from the group consisting of acetone, PGME, toluene, butyl acetate, PGMA, IPA MAK, EL, DIGLYME and TMAH is used, How to remove edge bead of blank mask. The method of claim 9, The solubilizing agent is a first solubilizer selected from the group consisting of acetone, EL and DIGLYME; Secondary solubilizers selected from the group consisting of MAK, butyl acetate, PGMA and TMAH; And sequentially supplying a third solubilizer selected from the group consisting of IPA, PGME, and toluene, How to remove edge bead of blank mask. The method of claim 10, The first dissolution is supplied in the range of 1 to 5 seconds, Supplying the second solution in a range of 1 to 3 seconds, The third dissolution is supplied in the range of 5 to 10 seconds, After each solubilizer is supplied, characterized in that for 10 to 100 seconds to dry, How to remove edge bead of blank mask. The method of claim 11, The drying is characterized in that the drying by rotating at a rotational speed equal to or less than the rotational speed of the rotating disc, How to remove edge bead of blank mask. The method of claim 9, Characterized in that the edge beads formed on the back side of the blank mask are removed using at least one of the solvents, How to remove edge bead of blank mask.

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