TW201909326A - Substrate processing apparatus, substrate processing method, mask cleaning method, and mask manufacturing method - Google Patents

Abstract

When a substrate with a back surface faced upward is cleaned by a scrubbing member or the like, foreign matters intrude onto a film surface due to intrusion of a cleaning liquid, resulting in an increased number of foreign matters which cannot be removed in film surface cleaning. A substrate processing device for processing a downward-facing surface by a processing liquid has a supporting member which supports the substrate from the downward-facing surface in a state where a main surface of the substrate is horizontal, a clamping member which holds the substrate by clamping, in two directions, a part of an outer edge portion of the substrate supported by the supporting member, driving means which, moves at least one of the supporting member and the clamping member in a vertical direction in order to separate, from the supporting member, the substrate held by the clamping member, scrub moving means which moves a scrubbing member along the downward-facing surface of the substrate while the scrubbing member is kept in contact with the downward-facing surface of the substrate in a space defined by the separation, and processing liquid supplying means for supplying the processing liquid to the downward-facing surface of the substrate.

Description

Substrate processing device, substrate processing method, photomask cleaning method, and photomask manufacturing method

The present invention relates to a substrate processing, and more particularly, to a substrate processing apparatus, a substrate processing method, a mask cleaning method, and a mask manufacturing method that are favorably used for cleaning processing of a mask substrate.

In a reticle for LSI (Large Scale Integration) or a reticle for FPD (Flat panel display), a pattern for transfer of a foreign matter generated during a manufacturing process or operation is attached to the reticle Areas, etc., resulting in poor transfer. Therefore, precise cleaning must be performed during the manufacturing process of the photomask.

Patent Document 1 describes a rotary cleaning device used in a plurality of masks of different sizes. The rotary cleaning device includes a device that reads the size information of the photomask substrate that is put in, and a control unit that performs specific control based on the read size information of the substrate. The rotary cleaning device has a structure in which a substrate reversing device is provided between the first cleaning tank and the second cleaning tank, and the driving unit for the clamping arm of the substrate reversing device is controlled based on the substrate size information. Hold the photomask substrate, thereby flipping the photomask substrate.

Patent Document 2 describes a substrate processing apparatus that supplies different processing liquids to the front and back surfaces of a substrate such as a glass substrate for a photomask to process the substrate. This substrate processing apparatus transports a substrate while the main surface of the substrate is horizontal, and supplies a first processing liquid to a front surface facing the substrate and a second processing liquid to a rear surface of the substrate, thereby processing the front and back surfaces of the substrate. This substrate processing apparatus is formed as a substrate processing apparatus which can prevent the cleaning liquid for the back surface from infiltrating the front surface of the substrate and can appropriately process the back surface of the substrate. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4824425 [Patent Document 2] Japanese Patent Laid-Open No. 2014-69126

[Problems to be solved by the invention]

As a method of treating the surface of a substrate using a liquid agent, spin cleaning is known. The rotating cleaning substrate rotates the horizontally held substrate in the processing shield, and the surface facing the substrate is supplied with a processing liquid to perform substrate processing. According to this rotary cleaning, a scrubbing material such as a brush or a sponge can be brought into contact with the substrate held horizontally to clean the substrate.

On the other hand, the substrate is held downward by a holding member (rotary chuck) for horizontally placing the substrate. Therefore, it is inconvenient to apply a contact type cleaning using a scrubbing material or the like to the lower side of the substrate. Therefore, when the front surface and the back surface of the substrate are cleaned separately by contact, after the substrate is cleaned and the upper surface is cleaned, the substrate must be inverted. However, the inversion of the substrate is accompanied by the following technical problems. Therefore, in the rotary cleaning device described in Patent Document 1, there is room for improvement in terms of not taking into consideration the problems that may be caused by the reversal of the substrate.

The substrate processing apparatus described in Patent Document 2 supplies a processing liquid while the substrate is transferred by a transfer roller while facing the back surface (downward) of the substrate. In this substrate processing apparatus, the back surface is processed without inverting the substrate. However, the back surface processing is performed while the substrate is transferred by the transfer roller. Therefore, when the back surface of the substrate is cleaned by using the substrate processing apparatus, contaminants remain on the back surface of the substrate due to the contact between the substrate and the transport roller.

Currently, for example, in a photomask substrate for FPD, in order to maximize the area of the main surface of the substrate as a transfer area, there is a need to arrange the device pattern near the outer edge of the substrate. Along with this, defects or foreign objects are not allowed near the outer edge of the substrate, and the range for allowing these is very small. In the substrate processing apparatus described in Patent Document 2, the conveyance roller is in contact with the back surface of the substrate, and contaminants remain on the contact portion. Therefore, this is applied to a photomask where the device pattern cannot be arranged near the outer edge of the substrate. Problems remain with this type of processing device.

The main object of the present invention is to provide a technology capable of obtaining a substrate with reduced contamination due to adhesion of foreign matter or the like by improving a cleaning method of the substrate facing downward. [Technical means to solve the problem]

(1st aspect) The 1st aspect of this invention is a substrate processing apparatus which processes the downward direction of a board | substrate by a processing liquid, and has a support member which sets the main surface of the said board | substrate horizontally. In the state, the substrate is supported from the lower side; the clamping member holds the substrate by holding a part of the outer edge portion of the substrate supported by the supporting member in two directions from the opposite direction; the driving device is for Separating the substrate held by the clamping member from the supporting member, and moving at least one of the supporting member and the clamping member in a vertical direction; scrubbing a moving device in a space formed by the separation, The scrubbing material is brought into contact with the downward direction of the substrate while the scrubbing material is moved downward along the substrate; and a processing liquid supply device that supplies the processing liquid to the downward direction of the substrate. (Second aspect) The second aspect of the present invention is the substrate processing apparatus according to the first aspect, wherein a front end of the clamping member is provided with a contact between a main surface and an end surface formed on the substrate. The contact surface of the corner surface. (Third aspect) A third aspect of the present invention is the substrate processing apparatus according to the first or second aspect described above, which includes a rotary device for rotating the substrate supported by the support member in a horizontal plane. (Fourth aspect) The fourth aspect of the present invention is a substrate processing method, which processes a substrate facing downward by a processing liquid, and has the following steps: The main surface of the quadrangle of the substrate is set horizontally. In the state, the substrate is provided by supporting the substrate from a lower side with a supporting member; the holding step clamps and holds a part of an outer edge portion of the substrate located on two opposite sides of the main surface of the substrate, respectively; A step of separating at least one of the substrate held by the substrate and the support member in a vertical direction to separate the lower surface of the substrate from the support member; and a processing step of supplying the substrate to the lower surface In the above-mentioned processing liquid, while the scrubbing material is brought into contact with the downward side of the substrate in the space formed by the separation, the scrubbing material is moved downward along the substrate, thereby processing the substrate with the processing liquid. Face down. (Fifth aspect) A fifth aspect of the present invention is a substrate processing method, which processes a substrate facing downward by a processing liquid and has the following steps: The main surface of the quadrangle of the substrate is set to a horizontal level. In a state, the substrate is provided by supporting the substrate from a lower side with a supporting member. The first holding step clamps and holds a part of an outer edge portion of the substrate located on two opposite sides of the main surface of the substrate. A separation step of separating at least one of the substrate and the support member clamped and held in the vertical direction to separate the substrate from the support member downward; a first processing step of The above-mentioned treatment liquid is supplied below, and in a space formed by the above separation, the scrubbing material is brought into contact with the downward side of the substrate while the scrubbing material is moved downward along the substrate, thereby treating the above with the treatment liquid. The substrate faces downward; the second holding step, which releases and clamps the outer edge portions of the substrate located on the two sides from being clamped and held, is different from the two sides A part of the outer edge portion of the substrate on both sides is clamped and held respectively; and a second processing step, which supplies the above-mentioned processing liquid to the lower side, and in the space, while the scrubbing material contacts the lower side of the substrate, The scrubbing material is moved along the downward direction of the substrate, thereby treating the downward direction of the substrate with a processing liquid. (Sixth aspect) The sixth aspect of the present invention is the substrate processing method according to the fifth aspect, wherein the substrate is rotated by a specific angle on a horizontal plane after the first processing step and before the second holding step. Its rotation steps. (Seventh aspect) The seventh aspect of the present invention is the substrate processing method according to the sixth aspect, wherein the specific angle is 90 degrees. (Eighth aspect) The substrate processing method according to the sixth or seventh aspect, wherein the rotating step is performed by supporting the substrate with the support member. (Ninth aspect) The ninth aspect of the present invention is the substrate processing method according to any one of the fourth to seventh aspects, wherein the back surface of the photomask substrate is cleaned by the substrate processing method. (Tenth aspect) A tenth aspect of the present invention is a photomask cleaning method, which includes: a back surface cleaning step by a substrate processing method according to any one of the fourth to seventh aspects described above. Cleaning the back surface of the photomask substrate; and a film surface cleaning step of cleaning the film surface of the photomask substrate with the film surface of the photomask substrate as an upper side; and There is no step of turning the mask substrate upside down between the steps of cleaning the film surface. (Eleventh aspect) The eleventh aspect of the present invention is a method for manufacturing a photomask, which includes the substrate processing method according to any one of the fourth to seventh aspects. (Twelfth aspect) A twelfth aspect of the present invention is a method for manufacturing a photomask, which includes the method for cleaning a photomask according to the tenth aspect. [Effect of the invention]

According to the present invention, by improving the cleaning method of the substrate facing downward, it is possible to obtain a substrate having reduced contamination due to adhesion of foreign matter or the like.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment of the present invention, the substrate to be processed by the substrate is, for example, a photomask substrate. The photomask substrate includes not only a transparent substrate used as a photomask (such as a glass substrate for photomasks), but also a photomask base formed by forming a specific film on the surface of the transparent substrate or a photoresist coated on the photomask base. Finished resist mask base or mask intermediate in the mask manufacturing process or completed mask. In the following description of the embodiment, the photomask substrate may be simply referred to as a substrate.

In the embodiment of the present invention, among the two main surfaces of the front surface and the back surface of the photomask substrate, one of the main surfaces is a film surface, and the other main surface is a back surface. The film surface refers to the surface on the side where film formation and pattern formation are performed. In many cases, the back surface becomes the exposed surface of glass, which is the material of the mask substrate. Therefore, in the embodiment of the present invention, the back surface of the mask substrate is also referred to as a glass surface.

Furthermore, in the embodiment of the present invention, when the main surface of the substrate is made horizontal during the substrate processing, the surface of the two main surfaces facing upward in the vertical direction is set to face upward, and the surface of the two main surfaces facing the vertical side is set to face upward. Face down.

<Rotary Washing Device> FIG. 1 is a schematic side view showing a configuration example of a rotary washing device as a reference example. The rotating cleaning device 50 shown in the figure includes a holder 51 that holds the photomask substrate 1 in a rectangular shape in plan view, a cover 52 that can hold the holder 51, a rotation shaft 53 that rotates the holder 51, and a driving unit. 54. It drives a rotating shaft 53; a scrubbing material 55 for cleaning; an upper processing liquid supply line 56; and a lower processing liquid supply line 57. The holder 51 is provided with a pin 58 for receiving and supporting the mask substrate 1 from below, and a chuck 59 for restricting an end surface near the four corners of the mask substrate 1. The drive unit 54 includes, for example, a drive source such as a motor, and a drive force transmission mechanism (pulley, belt, or the like) that transmits the drive force of the drive source to the rotation shaft 53. The scrubbing material 55 is configured using, for example, a brush or a sponge.

In the rotary cleaning device 50 including the above-mentioned structure, the photomask substrate 1 is placed on the holder 51, while the holder 51 and the photomask substrate 1 are rotated at high speed about the rotation shaft 53 as a center, while passing through the upper processing liquid supply line 56 A processing liquid (including a cleaning liquid and an eluent) is supplied to the upper surface of the photomask substrate 1. Thereby, the upper surface of the photomask substrate 1 can be processed by the processing liquid. At this time, if necessary, the processing liquid (including the cleaning liquid and the eluent) is ejected from the lower side of the substrate through the lower processing liquid supply line 57 to process the photomask substrate 1 downward with the processing liquid.

In the example shown in FIG. 1 described above, the upper surface of the photomask substrate 1 is a film surface, and a transfer pattern 1a is formed on the film surface. When the photomask is cleaned after the photomask is manufactured, foreign matter existing on the film surface side of the photomask substrate 1 must be eliminated as much as possible. Therefore, a contact cleaning mechanism using the scrubbing material 55 can be mounted on the rotary cleaning device 50. The contact cleaning mechanism is a mechanism in which, by holding an arm (not shown) of the scrubbing material 55, the scrubbing material 55 is disposed so as to face the upper surface (film surface) of the photomask substrate 1, and the The scrubbing material 55 is brought into contact with the upper surface of the photomask substrate 1 and is cleaned.

However, the photomask substrate 1 supports its own weight by being placed on the holder 51. Therefore, there is not much space on the lower surface side of the photomask substrate 1. Therefore, although the processing liquid sprayed from the lower processing liquid supply line 57 can be processed through the gap of the holder 51 to the downward direction of the photomask substrate 1, it is extremely difficult to apply contact cleaning using a scrubbing material or the like downward. The reason is that if a cleaning material or the like is to contact the lower surface of the photomask substrate 1 to remove the foreign matter more actively, a problem such as interference between the arm or the like holding the cleaning material and the holder 51 may occur.

Therefore, as a method of contacting and cleaning both the film surface and the back surface of the photomask substrate 1, before the film surface is processed, as shown in FIG. 2 (a), the photomask substrate 1 is placed on the holder with the film face down. 51. At this time, the upper surface is washed by the scrubbing material 55 described above. Thereafter, as shown in FIG. 2 (b), the photomask substrate 1 is turned upside down and placed on the holder 51. At this time, it is washed with the above-mentioned scrubbing material 55 to become a film surface facing upward. Furthermore, when the front and back surfaces of the photomask substrate 1 are contacted and cleaned, the film surface can also be cleaned first and then the back surface, but the foreign material on the film surface side should be removed as much as possible in the end, so it is advantageous The film surface treatment is finally performed.

However, the present inventors have found that even when the film surface treatment is performed last, when the previously cleaned surface becomes the upper surface, the foreign matter removed from the rear surface by washing or existing on the end surface of the photomask substrate 1 Foreign matter will also infiltrate the membrane surface side with the treatment liquid (Figure 3). That is, in the above-mentioned cleaning method, when foreign matter adhered to the back surface of the photomask substrate 1 or foreign matter adhered to the end surface of the photomask substrate 1 due to the operation of the photomask manufacturing process, etc., It will penetrate into the membrane surface side as shown by the dotted arrow in FIG. 3. In particular, when the roughness of the end surface of the mask substrate 1 is relatively coarse compared with the main surface, since a large amount of foreign matter is hidden in the end surface, the tendency of the foreign matter to penetrate into the film surface side becomes significant.

Furthermore, in the cleaning for removing foreign matter having a size less than 50 μm (for example, about 0.5 to 50 μm), the cleaning environment must be sufficiently cleaned. If the measures to prevent the pollution of the cleaning device or the scrubbing material, the dripping or re-attachment of the treatment liquid scattered in the cleaning device are not sufficient, it is possible to wash, but not reduce, the quantity of foreign matter. , But will increase the number of foreign objects. On the other hand, by rectifying the cleaning environment well, the number of foreign objects can be reduced by a specific ratio. However, even if it is possible to remove, for example, about 70% of foreign matter with one wash, it is almost impossible to achieve 100% removal in reality. Therefore, it is important to minimize the amount of foreign matter in the initial stage before cleaning the film surface in the substrate cleaning step. As described above, when the back surface of the photomask substrate 1 is cleaned first, and then the film surface of the photomask substrate 1 is cleaned later, foreign matter penetrates to the film surface side during the initial back surface cleaning. The number of foreign matters adhering to the film surface increases. As a result, in the cleaning of the film surface in the subsequent steps, the amount of foreign matter remaining without being completely removed tends to increase. That is, the present inventors found that it is desirable that there is no process for increasing the number of foreign matter on any side of the photomask substrate 1 in the cleaning step, and it is particularly advantageous to use a fine pattern (or a pattern already formed) The step of preventing the number of foreign objects on the film surface side from increasing temporarily.

Hereinafter, specific embodiments of the present invention based on the findings of the present inventors will be described.

<Substrate Processing Apparatus> FIG. 4 is a schematic side view showing a configuration example of a substrate processing apparatus according to an embodiment of the present invention. The substrate processing apparatus 10 shown in the figure can be applied, for example, as a substrate cleaning apparatus in which a photomask substrate is a substrate to be processed. In this case, the substrate processing apparatus 10 can be used to clean the mask substrate as required before or after each step (film formation, development, etching, inspection, defect correction, etc.) related to the manufacture of the mask. In particular, the mask substrate 1 according to the embodiment of the present invention exhibits a remarkable effect when the mask substrate in a patterned state is cleaned after a series of mask manufacturing processes, such as after the etching step and after the defect correction step.

The illustrated substrate processing apparatus 10 includes a holder 11 as a supporting member that supports a substrate, a clamping member 12 that holds an outer edge portion of the substrate, and a driving device 13 that is opposed to the substrate held by the clamping member 12. The holder 11 is driven in a manner of approaching and leaving; the scrubbing moving device 15 moves the scrubbing material 14; the upper surface-side processing liquid supply device 16 supplies the processing liquid to the upper surface of the substrate; It supplies a processing liquid to the lower side of the substrate; and a control unit 18 that controls the driving device 13 and the scrubbing moving device 15. Hereinafter, the substrate is described as the mask substrate 1. Among the two main surfaces of the photomask substrate 1, one of the main surfaces 2 is a film surface on which the transfer pattern 1a is formed, and the other main surface 3 is a rear surface including a glass surface.

As shown in the side view of FIG. 5 (a), the holder 11 is a member that supports the photomask substrate 1 from the lower surface side with the main surfaces 2 and 3 of the photomask substrate 1 being horizontal. The term “horizontal” refers to a case where it is substantially horizontal, and includes, for example, a case where the mask substrate 1 is deformed due to the influence of bending caused by its own weight. When the photomask substrate 1 is set on the substrate processing apparatus 10, the photomask substrate 1 is first placed on a holder 11. The holder 11 is used not only as a dedicated jig for the substrate processing apparatus 10, but also as a transport jig when the photomask substrate 1 is transferred to the substrate processing apparatus 10 from other steps, or as a support in other steps. A member of the photomask substrate 1. Therefore, the holder 11 is preferably attachable to and detachable from the substrate processing apparatus 10.

A plurality of pins 21 each having a columnar shape are provided on the upper surface of the holder 11. When the pins 21 are placed on the holder 11, the pins 21 support the photomask substrate 1 from the lower surface side by contacting the bottom surface of the photomask substrate 1. Each pin 21 is preferably located within a range of 10 mm from the outer edge of the main surface of the photomask substrate 1. In addition, the contact area between the main surface (facing downward) of the photomask substrate 1 and each pin 21 is small, for example, 100 mm ² or less in total. In order to reduce the above-mentioned contact area, the front end (upper end) of the pin 21 in contact with the main surface may also be formed into a convex curved shape, preferably a hemispherical shape. Moreover, each pin 21 is preferably set so as to be located near each of the four corners of the main surface of the mask substrate 1 having a quadrangular shape in plan view, as shown in the plan view of FIG. 5 (b).

The clamping member 12 is a member that holds a part of the outer edge of the substrate supported by the holder 11 in two directions facing each other and holds the substrate. The center axes of the pair of clamping members 12 are located on a straight line. The clamping members 12 preferably hold portions of two opposite sides of the main surface of the photomask substrate 1 respectively. Specifically, it can be set as the clamping member 12 which clamps and holds the outer edge part of the main surface of the mask substrate 1. Here, as shown in FIG. 6, the photomask substrate 1 has two main faces (2, 3) and four end faces 4, and is between the main faces 2 and 4 end faces 4 and the main faces 3 and 4 end faces 4. There are corner surfaces 5 between each. The clamping member 12 preferably has a contact surface that contacts the corner surface 5 of the photomask substrate 1. Thereby, the clamping member 12 can hold the photomask substrate 1 in a state where it does not come into surface contact with the main surface of the substrate on at least one side, but only in linear contact with the main surface. As shown in FIG. 6, at the front end of the clamping member 12, two contact surfaces 22 having an inclined angle with respect to the main surface of the reticle substrate 1 held by the clamping are formed by forming a cutout having a substantially trapezoidal cross section. The opening angle θ (deg) of the two contact surfaces 22 at the front end of the clamping member 12 is preferably such that the contact surface 22 can contact a corner surface formed between each of the main surfaces 2, 3 and the end surface 4 of the photomask substrate 1. 5 way setting. For example, it can be set to 70 ≦ θ ≦ 100.

Here, as shown in FIG. 7, when the mask substrate 1 is formed in a rectangular shape in plan view, and the length of the long side of the mask substrate 1 is W1 and the length of the short side is W2, the clamping member 12 holds the mask substrate 1. The contact length L (mm) can be set as follows, for example. That is, when the photomask substrate 1 is held by a pair of clamping members 12, the contact length L (mm) of the clamping member 12 in contact with the photomask substrate 1 in the lengthwise direction of the holding side is preferably considered for application. The minimum size of the mask substrate 1 of this device is set to 50 ≦ L ≦ 500. In this case, it is preferable that each of the opposing middle portions in the longitudinal direction or the vicinity thereof is held by one clamping member 12. In this case, the mask substrate 1 of various sizes with one side (long side, short side) of about 500 to 1500 mm can be held by the pair of clamping members 12.

Further, in FIG. 7, the case where the two opposite long sides of the photomask substrate 1 are held by a pair of clamping members 12 is shown. However, the above-mentioned setting of the contact length L (mm) can be similarly applied to The clamping member 12 holds the two short sides of the photomask substrate 1 opposite to each other. As shown in FIG. 8, when a plurality of pairs of clamping members are used and one side of the photomask substrate 1 is held by a plurality of clamping members 12 (two in the example of FIG. 8), each of the clamping members is preferably The contact lengths L1 and L2 of the tight members 12 are set to 50 to 200 mm, respectively, and the distance B1 between the adjacent clamp members 12 is set to 500 mm or less.

Also, as shown in FIG. 9, a configuration may be adopted in which two opposite sides of the photomask substrate 1 (long sides in the example of FIG. 9) are held by a pair of clamping members 12 a, and on the other hand, The other pair of clamping members 12b holds the two opposite sides of the photomask substrate 1 (the short sides in the example of FIG. 9). In this configuration, two pairs of clamping members 12a, 12b can hold the four sides of the photomask substrate 1 at the same time, or two pairs of clamping members 12a, 12b can alternately hold the opposite sides of the photomask substrate 1 (long sides or short sides). ). In addition, in FIG. 7 and the like, the design of the pattern of the mask substrate 1 to indicate the direction of the mask substrate 1 does not necessarily mean a realistic transfer pattern.

The clamp member 12 is attached to the front end of the arm 25 as shown in FIG. 4 described above. The arm 25 operates as follows. First, when it is necessary to hold the photomask substrate 1 by the clamp member 12, the arm 25 is moved forward so that the clamp member 12 contacts the outer edge portion of the photomask substrate 1 supported by the holder 11. In addition, when it is not necessary to hold the photomask substrate 1 by the clamping member 12, the arm 25 performs an avoidance operation to the outside of the holder 11 so that the clamping member 12 is separated from the outer edge portion of the photomask substrate 1. The operation of such an arm 25 is controlled by the control unit 18, and by performing control in a manner that the operations of the two arms 25 in a pair are synchronized, the pair of clamping members 12 also operate in synchronization.

The driving device 13 is driven to move at least one of the holder 11 and the clamping member 12 in the vertical direction so that the photomask substrate 1 held by the pair of clamping members 12 is separated from the holder 11. When the clamp member 12 is moved in the vertical direction, after the photomask substrate 1 is held by the clamp member 12 by the forward movement of the arm 25 described above, as shown in FIG. 10 (a), a pair of clamps The tightening member 12 moves upward in the vertical direction (hereinafter, also referred to as "rising"). When the holder 11 is moved in the vertical direction, as shown in FIG. 10 (b), after holding the photomask substrate 1 by a pair of clamping members 12, the holder 11 is moved downward in the vertical direction. (Hereinafter, also referred to as "down"). Thereby, the downward direction of the mask substrate 1 and the holder 11 can be separated in the vertical direction, so that the space of the downward direction of the mask substrate 1 can be enlarged.

When the photomask substrate 1 is separated from the holder 11 downward, the clamp member 12 may be raised and the holder 11 may be lowered. In addition, the clamping member 12 after being raised as shown in FIG. 10 (a) may be lowered to the original position, or the holder 11 after being lowered as shown in FIG. 10 (b) may be raised to the original position. The photomask substrate 1 and the holder 11 are relatively close to each other, and the space on the lower surface side of the photomask substrate 1 is closed. For example, when the photomask substrate 1 is transferred between the holder 11 and the clamp member 12, the photomask substrate 1 is brought closer to each other.

The driving device 13 also functions as a rotating device that rotates the photomask substrate 1 supported by the holder 11 in a horizontal plane. The rotating device rotates a rotation shaft 19 (FIG. 4) on which the holder 11 is horizontally mounted, thereby rotating the photomask substrate 1 supported by the holder 11 in a horizontal plane. Thereby, the arrangement posture (direction) of the mask substrate 1 in the horizontal plane can be changed. The rotation device can rotate the photomask substrate 1 at an angle of 90 degrees in a horizontal plane, for example.

Furthermore, in the present embodiment, the driving device 13 is configured to have the function of a rotating device, but the driving device 13 and the rotating device may be configured independently. When the substrate processing apparatus 10 is also provided with a function of a rotary cleaning device or a drying device, the rotation device may be a person who rotates the holder 11 at high speed.

The scrubbing moving device 15 introduces the downward-facing scrubbing material 14 for contacting and cleaning the photomask substrate 1 into the space formed on the bottom surface of the photomask substrate 1 through the driving device 13 described above. When the scrubbing moving device 15 separates the photomask substrate 1 from the holder 11 by the driving device 13, the scrubbing material 14 is moved in a space formed on the photomask substrate 1 toward the lower side by separation. In addition, the scrubbing moving device 15 moves the scrubbing material 14 along the downward direction of the photomask substrate 1 while bringing the scrubbing material 14 into contact with the downward direction of the photomask substrate 1. Thereby, the downward direction of the photomask substrate 1 can be cleaned by contacting the scrubbing material 14.

The scrubbing mobile device 15 can hold a scrubbing material 14 such as a sponge or a brush. In addition, when the scrubbing mobile device 15 needs to be cleaned by contacting the lower surface of the photomask substrate 1, the scrubbing material 14 is introduced into the space, and when the scrubbing moving material 15 is not needed, the scrubbing material 14 is retracted from the space. In addition, the scrubbing moving device 15 can move the scrubbing material 14 along the downward direction of the photomask substrate 1 while bringing the scrubbing material 14 into contact with the downward direction of the photomask substrate 1 (washing) net). Therefore, when the lower surface of the photomask substrate 1 is set to the XY plane, as shown in FIG. 11, the scrubbing moving device 15 moves the scrubbing material 14 horizontally in a specific route in the XY plane, so as to cover the lower surface. Holistic approach.

The scrubbing material 14 is preferably a disc brush or a sponge, and is preferably a disc shape (FIG. 12). As another scrubbing material, a roller brush can also be used. However, if a roller brush having a horizontal rotating shaft is used, foreign materials will be scattered together with the processing liquid splashed by the rotation of the roller brush, so that the foreign materials can easily adhere to the substrate. Therefore, in order to prevent upward contamination of the substrate due to foreign matter re-adhesion, it is preferable to use a disc-shaped scrubbing material 14 and treat (clean) the substrate while moving it only within the above XY plane.

The upper-surface-side processing liquid supply device 16 (FIG. 4) supplies the processing liquid to the upper surface of the photomask substrate 1 supported by the holder 11.

The lower surface-side processing liquid supply device 17 (FIG. 4) supplies the processing liquid to the lower side of the photomask substrate 1 held by the clamp member 12. For example, when the scrubbing material 14 is brought into contact with the mask substrate 1 and moved downward by the scrubbing moving device 15, a treatment liquid (washing liquid or eluent) is supplied near the contact surface between the mask substrate 1 and the scrubbing material 14. . Regarding the supplied treatment liquid, in order to make the residence time on the lower side of the photomask substrate 1 long, it is preferable to use a gel-like or foamy one having a high viscosity. Therefore, the processing liquid tank (not shown) to which the processing liquid supply device 17 on the lower surface side is connected may be a supply device accompanied by a stirrer or a gas (air, nitrogen, etc.) for generating foam.

The control unit 18 controls a control target according to a preset control program. The control target includes an arm 25 in addition to the driving device 13 and the scrubbing moving device 15. Therefore, the operations of the driving device 13, the scrubbing moving device 15, and the arm 25 are controlled by the control unit 18, respectively.

<Substrate Processing Apparatus> Next, a substrate processing method according to an embodiment of the present invention will be described with reference to FIGS. 13 and 14. 13 (a) to (f) and FIGS. 14 (a) to (f), the left side shows a side view, and the right side shows a top view.

The substrate processing method according to the embodiment of the present invention can be implemented using the substrate processing apparatus 10 configured as described above, or can be implemented using a substrate processing apparatus configured in another manner. Here, as an example, a substrate processing method using the substrate processing apparatus 10 configured as described above will be described. In the substrate processing method according to the embodiment of the present invention, a case will be described in which the mask substrate 1 on which the pattern for transfer is formed is set as a substrate to be processed, and the light on which the pattern for transfer is formed is used. The film surface of the cover substrate 1 is set to face upward, the back surface (glass surface) is set to face downward, and the surface of the cover substrate 1 is processed (washed, etc.) to face downward.

(Substrate processing method of the first embodiment) First, as shown in FIG. 13 (a), a photomask substrate 1 serving as a substrate to be processed is set in a substrate processing apparatus 10 (FIG. 4). Specifically, the photomask substrate 1 is placed on the holder 11 with the main surfaces 2 and 3 of the photomask substrate 1 being horizontal (setting step). At this time, the plurality of pins 21 provided on the holder 11 are brought into contact with the vicinity of the outer edge of the lower surface of the photomask substrate 1 to support the weight of the substrate from the lower surface of the photomask substrate 1.

Next, as shown in FIG. 13 (b), a pair of arms 25 (FIG. 4) facing each other are approached (moved forward) from a substantially horizontal plane with the mask substrate 1 to be held by a pair of clamping members 12 Photomask substrate 1. At this time, the clamping member 12 mounted on the front end of each arm 25 clamps and holds a part of the outer edge portion of the substrate located on two opposite sides (short sides in the illustration) of the main surface of the photomask substrate 1. Thereby, the photomask substrate 1 is held horizontally by being sandwiched from both sides by a pair of clamping members 12 (holding step, first holding step).

Next, as shown in FIG. 13 (c), the holder 11 is lowered by the driving device 13, thereby separating the photomask substrate 1 downward from the holder 11 (separating step). Thereby, a space of a specific height is formed between the lower surface of the mask substrate 1 and the holder 11. This space has a height that does not interfere even if the scrubbing mobile device 15 is introduced, and preferably has a height of about 40 to 80 cm. Here, although the holder 11 is lowered, the clamping member 12 holding the photomask substrate 1 may be raised. Further, the holder 11 may be lowered and the clamp member 12 may be raised.

Next, as shown in FIG. 13 (d), the scrubbing mobile device 15 is introduced into the space between the lower surface of the photomask substrate 1 and the holder 11, and the scrubbing material 14 mounted on the scrubbing mobile device 15 is placed in the space. The inner side is in contact with the downward side of the photomask substrate 1. The scrubbing material 14 is brought into contact with the downward direction of the photomask substrate 1 while the scrubbing material 14 is moved along the downward direction of the photomask substrate 1. At this time, the processing liquid is supplied to the lower side of the photomask substrate 1 by the lower-surface-side processing liquid supply device 17, thereby processing the processing liquid (cleaning processing in this embodiment) with the bottom surface of the photomask substrate 1 (processing Step, first processing step).

In this embodiment, a disk brush is used as the scrubbing material 14, and while the disk brush is rotated (rotated) at a specific speed, the disk brush is used to draw a specific trajectory on the lower surface of the mask substrate 1 as a whole. Way to move. The movement of the disc brush as the scrubbing material 14 may be, for example, a reciprocating motion shown by the dotted line in FIG. 12 described above. Further, it is preferable that a through hole penetrating in the longitudinal direction is formed in the center of the scrubbing material 14, and the processing liquid supply device 17 on the lower surface side ejects the processing liquid (washing liquid) through the through hole. The processing liquid is supplied to the contact surface of the photomask substrate 1 facing downward and the scrubbing material 14. The processing liquid supplied from the lower-surface-side processing liquid supply device 17 may be heated to about 30 to 60 degrees, for example. When the processing by the processing liquid is completed, the scrubbing material 14 and the scrubbing moving device 15 are allowed to escape from the space between the lower surface of the photomask substrate 1 and the holder 11.

Furthermore, when the photomask substrate 1 is to be held by the clamping member 12 and the entire lower surface of the photomask substrate 1 is cleaned by contact with the cleaning material 14, a part of the outer edge portion of the substrate where the clamping member 12 is present Due to the interference between the clamping member 12 and the scrubbing material 14, a region where the scrubbing material 14 cannot be brought into contact is generated. Specifically, as shown in FIG. 6 described above, there is a region where the front end portion of the clamping member 12 protrudes to the lower side of the photomask substrate 1 by a size d, and this region is caused by interference between the clamping member 12 and the scrubbing material 14. Untreated areas (unwashed areas) that have not been treated (washed). The area of the unwashed area varies depending on the shape of the clamping member 12 and the thickness of the photomask substrate 1. For example, the size d is about 2 to 50 mm. Generally speaking, the thickness of the substrate is different from the substrate size (length dimension of each side) of the photomask substrate 1. Therefore, as a photomask for display device manufacturing, in order to handle various substrates of different sizes, this tendency cannot be resolved. avoid.

Next, as shown in FIG. 13 (e), the holder 11 that has been lowered in order to expand the space is raised by the driving device 13, and the photomask substrate 1 is set on the holder 11 again.

Next, as shown in FIG. 13 (f), the outer edge of the substrate on the two opposite sides of the photomask substrate 1 (the short side in the illustration) is moved away from the holder 25 by avoiding the arm 25. The clamping and holding of the clamping member 12 is released. Accordingly, the photomask substrate 1 is in a state of being supported by the holder 11 having the plurality of pins 21 from the lower side again. At this stage, the above-mentioned unprocessed area (unwashed area) 1b exists on the lower side of the photomask substrate 1.

Next, as shown in FIG. 14 (a), the holder 11 is rotated by 90 degrees (or 270 degrees) in the horizontal plane by the driving device 13 (rotation step). Thereby, the directions of the long side and the short side of the mask substrate 1 are switched in a horizontal plane.

Next, as shown in FIG. 14 (b), by bringing the pair of arms 25 closer (forward movement) again, the clamping member 12 is clamped and held at a position different from the two sides of the clamped and held in FIG. 13 (b). The outer edges of the substrate on both sides (long sides in the illustration) (second holding step).

Next, as shown in FIG. 14 (c), the holder 11 is lowered again by the driving device 13, so that the lower surface of the photomask substrate 1 is separated from the holder 11, so that the lower surface of the photomask substrate 1 and the holder are separated. A space of a certain height is formed between 11.

Next, as shown in FIG. 14 (d), the scrubbing moving device 15 is introduced again between the lower surface of the photomask substrate 1 and the holder 11, and the scrubbing material 14 is brought into contact with the photomask substrate 1 in this space. Next, the entire lower surface of the photomask substrate 1 is treated with a processing liquid (cleaning liquid) while the scrubbing material 14 is moved downward along the photomask substrate 1 (second processing step). At this time, since the scrubbing material 14 is also in contact with the untreated area (unwashed area) 1b, the untreated area 1b disappears. As a result, the entire downward cleaning including the untreated region 1b is completed.

Next, as shown in FIG. 14 (e), the holder 11 that has been lowered in order to expand the space is raised by the driving device 13, thereby setting the photomask substrate 1 on the holder 11 again.

Next, as shown in FIG. 14 (f), by making the arm 25 avoid to the outside of the holder 11, the outer edge portion of the substrate located on two opposite sides of the photomask substrate 1 (long side in the illustration) The clamping and holding of the clamping member 12 is released. Thereby, the photomask substrate 1 is restored to the state supported by the several pins 21 provided in the holder 11 from the lower side.

According to the substrate processing apparatus 10 and the substrate processing method using the same, even if the photomask substrate 1 is not turned upside down, the entire surface of the photomask substrate 1 supported by the holder 11 can be processed with the cleaning solution 14 using the processing liquid. Therefore, when the back surface of the photomask substrate 1 is cleaned downward, it is possible to prevent foreign matter and the like from penetrating into the film surface side due to the back surface cleaning, thereby reducing contamination caused by the adhesion of the foreign matter and the like. In addition, according to this substrate processing method, the opposite long side and the short side of the photomask substrate 1 are clamped and held once each, so that the entire lower surface can be processed. The clamped part will not be clamped again. Regarding the photomask substrate 1 having a quadrangular (square or rectangular) main surface, the simplest movement that can be alternately held from two orthogonal directions can be quickly processed to the entire lower surface.

(Substrate processing method of the second embodiment) The substrate processing method of the second embodiment of the present invention is different from the first embodiment described above in the following points. First, in the step of FIG. 13 (b) or FIG. 14 (b) described above, the photomask substrate 1 is held by a pair of clamping members 12. At this time, if the mask substrate 1 is bent due to its own weight, the height of the center of gravity position of the mask substrate 1 becomes lower than the height of the outer edge portion of the substrate held by the clamping member 12. Therefore, if the scrubbing material 14 is moved on a horizontal surface, the downward pressure of the scrubbing material 14 on the photomask substrate 1 may become uneven or the contact state between the two may not be maintained properly.

Therefore, in the second embodiment of the present invention, as shown in FIG. 15, when the horizontal plane is the XY plane, the scrubbing moving device 15 can not only move the scrubbing material 14 in the XY plane, but also make the scrubbing material 14 on Move in a three-dimensional direction including the Z direction. Specifically, it is preferable to have a configuration in which the scrubbing moving device 15 is controlled by the control unit 18 (FIG. 4), and the scrubbing material 14 can be moved in contact with the concave-convex shape of the mask substrate 1 in a downward shape. In this case, for example, based on the shape (vertical and horizontal dimensions, thickness) of the photomask substrate 1 and the physical properties of the material, the curved shape of the photomask substrate 1 when it is bent by its own weight is estimated in advance, and the downward shape calculated in conjunction with the estimated shape is three-dimensionally calculated. The movement of the scrubbing material 14 is controlled. Thereby, even when the photomask substrate 1 is bent due to its own weight, the scrubbing material 14 can be moved downward along the photomask substrate 1 by following the curved shape. Therefore, the scrubbing material 14 can be brought into contact with the entire lower surface of the photomask substrate 1 with a uniform pressure.

(Substrate processing method of the third embodiment) In the substrate processing method of the first embodiment described above, the photomask substrate 1 clamped and held by the clamping member 12 is horizontally maintained so that the scrubbing material 14 and the substrate face downward. The composition of contact. On the other hand, in the third embodiment, as shown in FIG. 16, a configuration is adopted in which the reticle substrate 1 clamped and held by the clamping member 12 is held at a predetermined angle with reference to a horizontal plane. Specifically, in the step of FIG. 13 (b) or FIG. 14 (b) described above, the photomask substrate 1 clamped and held by the clamping member 12 is inclined at a specific angle (about 2 to 20 degrees) in this state. The processing liquid (washing liquid) 30 is supplied from the bottom toward the upstream side (higher side) from the bottom through the processing liquid supply means 17 (FIG. 4) on the lower surface side. Thereby, as shown by the dotted arrow in FIG. 16, the processing liquid 30 flows from the upstream side of the mask substrate 1 toward the lower side toward the downstream side (lower side). That is, the flow direction of the processing liquid 30 can be controlled to a fixed direction under the mask substrate 1. Therefore, stagnation or irregular dripping of the treatment liquid 30 can be suppressed. In addition, in the third embodiment, the scrubbing moving device 15 is configured to move the scrubbing material 14 in a three-dimensional direction, and the movement of the scrubbing material 14 can be controlled three-dimensionally in accordance with the inclination of the photomask substrate 1. Therefore, the scrubbing material 14 can be brought into contact with the entire lower surface of the photomask substrate 1 with a uniform pressure.

(Other embodiment) In the said embodiment, although the case where the mask substrate 1 was hold | maintained using the pair of clamp members 12 was demonstrated, for example, as shown in FIG. 9 mentioned above, two pairs of clamp members 12 (12a, 12b) When the photomask substrate 1 is held, the steps (rotation steps) of FIGS. 13 (e), (f), and 14 (a) described above may be omitted. Specifically, when the above-mentioned step of FIG. 13 (d) is ended, in addition to holding one pair of clamping members 12a on opposite sides (short sides) of the photomask substrate 1 so far, another pair of clamping members 12a is also clamped. The member 12b holds two sides different from the two sides. Next, after the clamp holding of the pair of clamp members 12a is released, the photomask substrate 1 is treated (washed) with the scrubbing material 14 facing downward with the treatment liquid. Next, by raising the holder 11, the photomask substrate 1 is set on the holder 11 again, and the clamping and holding of the pair of clamping members 12 b is released. This simplifies the steps compared with the first embodiment. Therefore, the photomask substrate 1 can be processed efficiently.

In the above-mentioned embodiment, the case where the photomask substrate 1 is processed downward has been described. However, at the same time, the photomask substrate 1 may be processed upward by using a scrubbing moving device or a scrubbing material. That is, the substrate processing apparatus according to the embodiment of the present invention includes an aspect that additionally includes a scrubbing moving device or a scrubbing material for processing the photomask substrate 1 and further includes a processing liquid that supplies a processing liquid upward. The device is supplied, and its operation is controlled by the control unit.

In addition, after using the substrate processing method of the embodiment of the present invention to clean the back surface of the photomask substrate 1 with the scrubbing material 14 and the cleaning liquid as the bottom surface, the photomask substrate may be cleaned using a well-known rotary cleaning device. 1 film surface. In this process, it is not necessary to flip the photomask substrate 1 up and down. In this case, a photomask cleaning method is realized, which includes a back surface cleaning step of cleaning the back surface with the back surface of the photomask substrate 1 as the lower surface, and a state where the film surface of the photomask substrate 1 is the upper side. The film surface cleaning step of washing the film surface of the photomask substrate 1 underneath, and there is no step of turning the photomask substrate 1 upside down between the above-mentioned back surface cleaning step and the film surface cleaning step. In this photomask cleaning method, since the back surface of the photomask substrate 1 is cleaned with the film surface facing upward, the risk of foreign matter penetrating to the film surface side during back surface cleaning can be reduced.

In the above embodiment, as the substrate to be processed in the substrate processing apparatus 10 or the substrate processing method, the photomask substrate 1 has been described as an example, but the type or application of the substrate to be processed is not particularly limited. . In the case of cleaning the photomask substrate 1, the specifications or uses of the photomask are not particularly limited. For example, the substrate processing apparatus 10 or the substrate processing method according to the embodiment of the present invention can be preferably applied to a case of processing a photomask substrate for manufacturing a display device (a liquid crystal panel, an organic electroluminescence panel, or the like). As a photomask substrate for manufacturing a display device, for example, a photomask substrate having a main surface having a quadrangular shape with a side of about 300 to 2000 mm and a thickness of about 5 to 20 mm can be applied. In particular, if it is applied to a display device having a patterned CD (Critical Dimension) critical (for example, CD = 3 μm or less, or about 1 to 3 μm) hole pattern or L / S (line / gap) pattern, the light is used for a display device. The cover substrate has a significant effect. These photomask substrates can be provided by an FPD exposure device (having any or all of the i-line, h-line, and g-line light sources, a projection exposure device with an NA (numerical aperture) of the optical system of about 0.08 to 0.15, or Proximity exposure devices with the same light source, etc.), transfer the transfer pattern to the object to be transferred.

The present invention can be realized in the form of a mask manufacturing method including the substrate processing method of the above-mentioned embodiment, and also can be realized in the form of a mask manufacturing method including the above-mentioned back surface cleaning step and film surface cleaning step.

The photomask manufacturing method has the following steps, for example. A step of preparing a resist-attached photomask substrate, the above-mentioned resist-attached photomask substrate is formed on the main surface of the photomask to form at least one optical film (such as a light-shielding film), and then forms a photoresist film by coating. The step of drawing the pattern data based on the design of the device to be obtained onto the mask substrate using a drawing device using a laser or an electron beam. The step of developing the patterned photoresist film to form a resist pattern. And using the formed resist pattern as an etching mask to etch the optical film by dry etching or wet etching to form a pattern for transfer. The formed transfer pattern is inspected, and if necessary, a pattern defect correction step is performed. In any of these steps, a substrate processing method or a mask cleaning method according to an embodiment of the present invention can be applied.

1‧‧‧ photomask substrate

1a‧‧‧ transfer pattern

1b‧‧‧Untreated area

2‧‧‧ main face

3‧‧‧ main face

4‧‧‧face

5‧‧‧ corner surface

10‧‧‧ substrate processing equipment

11‧‧‧ retainer

12‧‧‧ clamping member

12a‧‧‧ clamping member

12b‧‧‧ clamping member

13‧‧‧Driver

14‧‧‧Scouring material

15‧‧‧ Scrub mobile device

16‧‧‧ Upper surface side treatment liquid supply device

17‧‧‧ Lower surface side treatment liquid supply device

18‧‧‧Control Department

19‧‧‧Rotary shaft

21‧‧‧pin

22‧‧‧contact surface

25‧‧‧arm

30‧‧‧ treatment liquid

50‧‧‧ rotating washing device

51‧‧‧ retainer

52‧‧‧Shield

53‧‧‧rotation axis

54‧‧‧Driver

55‧‧‧Scouring material

56‧‧‧ Upper processing liquid supply line

57‧‧‧ lower processing liquid supply line

58‧‧‧pin

59‧‧‧Chuck

A‧‧‧Part

B1‧‧‧Interval

d‧‧‧size

L‧‧‧ contact length

L1‧‧‧Contact length

L2‧‧‧ contact length

W1‧‧‧length of long side

W2‧‧‧length of short side

X‧‧‧ direction

Y‧‧‧ direction

Z‧‧‧ direction

θ‧‧‧ opening angle

FIG. 1 is a schematic side view showing a configuration example of a rotary cleaning device as a reference example. FIG. 2 (a) is a schematic side view showing a configuration when a back surface of a substrate is cleaned by a cleaning material using the cleaning device shown in FIG. 1, and (b) is a rotary cleaning device shown in FIG. 1 A schematic side view of the arrangement when the film surface of the substrate is cleaned with a scrubbing material. FIG. 3 is a schematic side view illustrating the infiltration of foreign matter when the back surface of the substrate is cleaned. 4 is a schematic side view showing a configuration example of a substrate processing apparatus according to an embodiment of the present invention. Fig. 5 (a) is a schematic side view showing the structure of the retainer, and (b) is a schematic plan view showing the pin arrangement of the retainer. FIG. 6 is an enlarged view of part A of FIG. 4. FIG. 7 is a schematic plan view (part 1) showing an example of holding the substrate by the clamping member. FIG. 8 is a schematic plan view (No. 2) showing an example of holding the substrate by the clamp member. FIG. 9 is a schematic plan view (No. 3) showing an example of holding the substrate by the clamping member. FIG. 10 (a) is a schematic side view showing an example in which the clamping member is moved upward in the vertical direction to separate the substrate from the holder, and (b) is a view showing the substrate moved in the vertical direction to move the substrate downward. A schematic side view of an example of separation from the holder. FIG. 11 is a schematic side view showing a state where the scrubbing moving device is introduced into a space between the lower surface of the substrate and the holder and the scrubbing material is moved. Fig. 12 is a perspective view showing an example of a shape and a movement track of a scrubbing material. 13 (a) to (f) are diagrams (No. 1) illustrating a substrate processing method according to the first embodiment of the present invention. 14 (a) to (f) are diagrams (No. 2) illustrating a substrate processing method according to the first embodiment of the present invention. FIG. 15 is a diagram illustrating a substrate processing method according to a second embodiment of the present invention. FIG. 16 is a diagram illustrating a substrate processing method according to a third embodiment of the present invention.

Claims (12)

A substrate processing apparatus that treats a substrate facing downward with a processing liquid and includes: a supporting member that supports the substrate from a lower side with a main surface of the substrate being horizontal; a clamping member To hold a part of the outer edge of the substrate supported by the supporting member in two directions from the opposite direction to hold the substrate; a driving device for separating the substrate held by the clamping member from the supporting member And at least one of the support member and the clamping member is moved in the vertical direction; the scrubbing moving device, in the space formed by the separation, makes the scrubbing material contact the downward side of the substrate, while making The scrubbing material moves downward along the substrate; and a processing liquid supply device that supplies the processing liquid to the lower surface of the substrate. The substrate processing apparatus according to claim 1, wherein a contact surface that can contact a corner surface formed between the main surface and the end surface of the substrate is provided at the front end of the clamping member. The substrate processing apparatus according to claim 1 or 2, further comprising a rotating device for rotating the substrate supported by the support member in a horizontal plane. A substrate processing method includes processing a downward direction of a substrate by a processing liquid and having the following steps: in a state where a main surface of a quadrangle of the substrate is set horizontally, the above is supported by a supporting member from a lower surface side The substrate is provided with the substrate. The holding step clamps and holds a part of an outer edge portion of the substrate located on two opposite sides of the main surface of the substrate. The separation step includes the substrate being clamped and held. And moving at least one of the supporting member in a vertical direction to separate the substrate from the lower surface and the supporting member; and a processing step of supplying the processing liquid to the lower surface and forming a space formed by the separation Inside, while the scrubbing material is brought into contact with the downward direction of the substrate, the scrubbing material is moved along the downward direction of the substrate, thereby processing the downward direction of the substrate with a processing liquid. A substrate processing method includes processing a substrate facing downward with a processing liquid and having the following steps: in a state in which a main surface of a quadrangle of the substrate is horizontal, the substrate is supported from a lower side by a supporting member The substrate is provided with the substrate. The first holding step clamps and holds a part of an outer edge portion of the substrate located on two opposite sides of the main surface of the substrate, respectively. The separation step includes the clamping and holding of the above. At least one of the substrate and the supporting member is moved in a vertical direction to separate the substrate from the lower surface and the supporting member. The first processing step is to supply the processing liquid to the lower surface and to form the substrate by the separation. In the space, while the scrubbing material is in contact with the downward direction of the substrate, the scrubbing material is moved along the downward direction of the substrate, thereby processing the downward direction of the substrate with the processing liquid; the second holding step, which will be located in the above The outer edge portion of the substrate on both sides is released from the clamping and holding, and will be part of the outer edge portion of the substrate on two sides different from the above two sides. Clamping and holding respectively; and a second processing step, which supplies the above-mentioned processing liquid to the downward side, and in the space, one side makes the scrubbing material contact the downward side of the substrate, and the other side makes the scrubbing material down the substrate. By moving, the downward side of the substrate is processed with the processing liquid. The substrate processing method according to claim 5, further comprising a step of rotating the substrate by a specific angle on a horizontal plane after the first processing step and before the second holding step. The substrate processing method according to claim 6, wherein the specific angle is 90 degrees. The substrate processing method according to claim 6 or 7, wherein the rotation step is performed by supporting the substrate by the support member. The substrate processing method according to any one of claims 4 to 7, wherein the back surface of the photomask substrate is cleaned by the above substrate processing method. A photomask cleaning method comprising: a back surface cleaning step for cleaning the back surface of a photomask substrate by a substrate processing method according to any one of claims 4 to 7; and a film surface cleaning step for performing In a state where the film surface of the photomask substrate is on the upper side, the film surface of the photomask substrate is cleaned; and between the rear surface cleaning step and the film surface cleaning step, there is no means for turning the photomask substrate upside down step. A photomask manufacturing method including the substrate processing method according to any one of claims 4 to 7. A photomask manufacturing method including the photomask cleaning method according to claim 10.