TW201802575A - Surface treatment method and mask, and surface treatment device - Google Patents

Abstract

The purpose of the present invention is to provide a surface treatment method with which it is possible to perform, efficiently and at a high resolution, a surface treatment using vacuum UV light on an item to be treated, a mask used in the surface treatment method, and a surface treatment device. In the present invention, when an item to be treated is irradiated with vacuum UV light in the presence of oxygen through a mask in which a patterned light-shielding part is formed on the surface of a light-transmitting substrate, whereby a specific surface-modified region is formed on the surface of the item to be treated, a mask in which the thickness of the region forming a translucent part on the light-transmitting substrate is less than that of the region in which the light-shielding part is formed, or a mask in which the difference between the surface level of the light-shielding part and the surface level of a translucent part adjacent to the light-shielding part is 1 [mu]m or greater is used.

Description

Surface treatment method, mask and surface treatment device

The present invention relates to a surface treatment method using, for example, vacuum ultraviolet light emitted from an excimer lamp, a mask used in the surface treatment method, and a surface treatment apparatus for performing the surface treatment method.

In recent years, vacuum ultraviolet light having a wavelength of 200 nm or less (hereinafter, also referred to as "VUV") is used in various fields. For example, instead of using a patterning process due to photoresist, a technique of patterning a self-assembled monomolecular film (hereinafter also referred to as a "SAM film") using VUV and a mask to cause a chemical reaction with VUV is not used.

For example, Patent Document 1 describes a photomask in which a light-shielding pattern of Cr is formed on the surface of a substrate of quartz or fluorite, an organic molecular film is formed on the patterning substrate, and the organic molecular film is transmitted through the photomask to irradiate vacuum ultraviolet light in a pattern. A method for decomposing and removing organic molecular film in a place irradiated with vacuum ultraviolet light. It is described that an excimer lamp is used as the vacuum ultraviolet light source.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-324816

In the pattern forming method using such vacuum ultraviolet light, a part of the organic molecular film is decomposed and removed by the action of vacuum ultraviolet light to form a pattern. Therefore, it is necessary to allow oxygen that acts on vacuum ultraviolet light to exist on the surface of the substrate for pattern formation. Here, when the photomask is in contact with the patterning substrate, the light-shielding pattern of Cr is generally a very thin film. Therefore, the oxygen acting on the vacuum ultraviolet light is insufficient, requires long-term exposure, or the patterning itself is difficult to perform.

On the other hand, the light emitted from an excimer lamp used as a vacuum ultraviolet light source is divergent light, so if the interval between the light-shielding pattern of the mask and the organic molecular film is set to be large, the light will also go around the corresponding mask. The area of the light-shielding pattern has a problem that the accuracy of the pattern is reduced.

In recent years, in order to increase the number of substrates for pattern formation per exposure process, the size of the mask has gradually increased.

However, in a large-sized mask, the mask is warped or distorted due to its own weight, so it is difficult to suppress the interval between the light-shielding pattern of the mask and the organic molecular film, which may cause a problem in that the accuracy of the pattern is reduced.

The present invention was conceived by the inventors in view of the above circumstances, and an object thereof is to provide a surface treatment method capable of performing a surface treatment of a to-be-processed object using vacuum ultraviolet light at a high resolution and efficiently and in the surface treatment method. Masks and surface treatment devices used.

In the surface treatment method of the present invention, in the presence of oxygen, a mask of a patterned light-shielding portion is transmitted through the surface of a light-transmitting substrate, and vacuum ultraviolet light is irradiated to the object to be treated, thereby applying the object to the object to be treated. The surface treatment method for forming a specific surface modified region on the surface of the substrate is characterized in that, as the mask, a thickness of a region where the light-transmitting portion of the light-transmitting substrate is formed is smaller than a thickness of the region where the light-shielding portion is formed.

In the surface treatment method of the present invention, a mask of a patterned light-shielding portion is formed through the surface of a light-transmitting substrate in the presence of oxygen, and vacuum ultraviolet light is irradiated to the object to be treated. The method for forming a specific surface-modified region on the surface of a processed object is characterized in that, as the mask, a surface level of a light-shielding portion is used, and a difference between a surface level of a light-transmitting portion adjacent to the light-shielding portion is 1 μm or more.

The mask of the present invention is a mask for forming a patterned light-shielding portion on the surface of a light-transmitting substrate, wherein the thickness of a region where the light-transmitting portion is formed on the light-transmitting substrate is smaller than The thickness of the area.

The mask of the present invention is a mask that forms a patterned light-shielding portion on the surface of a light-transmitting substrate, wherein the surface level of the light-shielding portion and the surface of the light-transmitting portion adjacent to the light-shielding portion are characterized in that The difference in level is 1 μm or more.

The surface treatment device of the present invention is characterized by: Equipped with: a workpiece table, which is arranged in a processing chamber set in an atmosphere where oxygen is present, and has a flat object-to-be-processed surface; a vacuum ultraviolet light source, which is arranged in a space separated from the internal space of the processing chamber, and The vacuum ultraviolet light is transmitted through the mask and irradiates the object to be processed on the workpiece stage; and the mask holding mechanism is to hold the mask; the aforementioned vacuum ultraviolet light source is an excimer lamp; the aforementioned mask is the aforementioned mask, and In a state where the surface on which the light-shielding portion is formed and the object-to-be-processed object-mounting surface of the workpiece stage face each other, it is held by the aforementioned mask holding mechanism.

The mask of the present invention is set at the surface level of the patterned light-shielding portion formed on the surface of the flat light-transmitting substrate, and the surface level of the light-transmitting portion formed by exposing the surface of the light-transmitting substrate. The structure having a relatively large difference can sufficiently secure the amount of oxygen existing in the space partitioned by the adjacent light-shielding portions. Therefore, in a situation where the mask is used in close contact with the object to be processed, the mask can be avoided from being bent due to its own weight, resulting in a decrease in resolution.

Therefore, according to the surface treatment method and the surface treatment device using such a mask, the active oxygen or ozone generated by the vacuum ultraviolet light can indeed help the treatment of the object to be treated, so the object can be efficiently processed. The desired treatment of things. Moreover, even if the mask is used in close contact with the object to be processed, In the situation, the situation of oxygen depletion as an active species source can also be avoided. Therefore, the thickness of the light-transmitting substrate constituting the mask can be reduced, the vacuum ultraviolet light from the excimer lamp can be efficiently transmitted, and the processing efficiency can be improved. In addition, since the size of the mask itself can be increased, production efficiency can be improved.

10a‧‧‧Mask

10b‧‧‧Mask

11‧‧‧light transmitting substrate

11a‧‧‧ convex

12‧‧‧Transmission Department

15‧‧‧Shading Department

16‧‧‧Light-shielding film

16a‧‧‧Shading film forming layer

17‧‧‧ lower light-shielding film

17a‧‧‧ lower light-shielding film forming layer

18‧‧‧ Upper layer light-shielding film

20‧‧‧Photoresist pattern

20a‧‧‧Photoresistive layer

30‧‧‧Processing Room

31‧‧‧Frame

32‧‧‧ Suction port

32a‧‧‧Flow path opening and closing valve

33‧‧‧ exhaust port

33a‧‧‧Flow path opening and closing valve

35‧‧‧ Light Room

36‧‧‧shell

38‧‧‧Window components

40‧‧‧ Excimer Light

45‧‧‧Mask holding mechanism

46‧‧‧Mask

50‧‧‧Workbench

50a‧‧‧ object mounting surface

55‧‧‧Platform mobile mechanism

W‧‧‧ substrate material (substrate to be processed)

[Fig. 1] An enlarged sectional view for explaining a specific structural example of a mask of the present invention.

[Fig. 2] A cross-sectional view for explaining an example of a method for manufacturing a mask of the present invention.

Fig. 3 is a cross-sectional view for explaining another example of a method for manufacturing a mask of the present invention.

[FIG. 4] An explanatory sectional view schematically showing the structure of an example of the surface treatment apparatus of the present invention.

[Fig. 5] An enlarged view showing a part of the surface treatment apparatus shown in Fig. 4. [Fig.

Fig. 6 is a cross-sectional view for explaining the structure of another example of the surface treatment apparatus of the present invention.

FIG. 7 is a graph showing the relationship between the difference between the surface level of the light transmitting portion of the mask and the surface level of the light shielding portion, and the processing time.

Hereinafter, embodiments of the present invention will be described in detail. Bright.

The surface treatment method of the present invention uses vacuum ultraviolet light to form a specific surface modified region by performing a fine selective surface modification of the surface of the object to be treated. Specifically, for example, a pattern forming substrate on which an organic monomolecular film (SAM) is provided on the surface is set as a to-be-processed object, and a part of the organic monomolecular film is removed. In addition, for example, when a conductive ink is directly applied to a metal substrate such as a glass substrate, a wafer, a resin plate, or a film by an inkjet or the like, or when an adhesive is applied by a dispenser, etc. If the adhesive is exceeded, the substrate may be partially washed or partially hydrophilized.

In the surface treatment method of the present invention, for example, vacuum ultraviolet light (VUV) having a wavelength of 200 nm or less is used.

The vacuum ultraviolet light source may be any one that emits vacuum ultraviolet light, but from the viewpoint that vacuum ultraviolet light in a necessary wavelength region can be obtained at a high intensity, an excimer lamp is preferably used. Specifically, for example, a xenon excimer lamp (a peak wavelength of 172 nm) is suitably used.

In the surface treatment method of the present invention, it is necessary to generate active oxygen or ozone by vacuum ultraviolet light. Therefore, in an atmosphere where oxygen exists, for example, an atmosphere containing oxygen, ultraviolet light irradiation treatment is performed on the object.

In the ultraviolet light irradiation treatment, the vacuum ultraviolet light is irradiated to the surface of the object to be processed through the mask.

The mask is, for example, a patterned light-shielding portion formed on the surface of a flat light-transmitting substrate, and the light-transmitting portion is formed to expose the surface of the light-transmitting substrate. The difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion is 1 μm or more.

The difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion is, for example, preferably 1 μm or more, and preferably 1000 μm or less.

As a material constituting the light-transmitting substrate, for example, any material that transmits vacuum ultraviolet light may be used, and for example, synthetic quartz glass, sapphire, CaF, or the like can be used. The thickness of the light-transmitting substrate is preferably from 1 to 10 mm from the viewpoint of the transmittance of vacuum ultraviolet light.

The light-shielding portion is formed by forming a light-shielding film on the surface of the light-transmitting substrate. As a material constituting the light-shielding film, for example, metals such as chromium, copper, nickel, gold, platinum, metal oxides such as chromium oxide, titanium oxide, and nitrides such as silicon nitride and titanium nitride can be used.

The light-shielding film may be a single-layer film made of a metal selected from the foregoing metals, metal oxides, and nitrides, and may be a laminated film made of two or more of these. From a viewpoint, a metal film such as nickel, gold, platinum, or the like is preferably a laminated film composed of a layer made of a metal oxide.

A specific structural example of a mask used in the surface treatment method of the present invention is disclosed in FIG. 1.

The mask 10a shown in FIG. It is configured such that the difference ΔL between the surface level Lt of the light transmitting portion 12 and the surface level Ls of the light shielding portion 15 is a predetermined size. Specifically, due to the light-transmitting substrate The area 11 where the light transmitting portion 12 is formed has a predetermined depth 11 a. The thickness t1 of the light transmitting substrate 11 where the light transmitting portion 12 is formed is smaller than the thickness t2 of the area where the light shielding portion 15 is formed. In the mask 10a, the thickness of the light shielding film 16 is, for example, 0.06 to 0.1 μm.

The mask 10b shown in FIG. 1 (b) is a difference ΔL between the surface level Lt of the light transmitting portion 12 and the surface level Ls of the light shielding portion 15 by increasing the thickness of the light shielding film 16 constituting the light shielding portion 15. It is constituted in a manner of a predetermined size. The light-transmitting substrate 11 has a uniform thickness.

The light-shielding film 16 in this example is, for example, a lower-layer light-shielding film 17 formed by a metal film such as a chromium film, and an upper-layer light-shielding film 18 formed by a metal oxide film such as a chromium oxide film formed on the surface of the lower-layer light-shielding film 17. Made of laminated film.

The masks 10a and 10b can be produced as described below.

To describe a method for manufacturing the mask 10a shown in FIG. 1 (a), first, as shown in FIG. 2 (a), a mask material is prepared on the entire surface of the light-transmitting substrate 11 to form a light-shielding film forming layer 16a. (Blanks), a photoresist is applied on the surface of the light shielding film forming layer 16 of the masking material to form a photoresist layer 20a. The photoresist may be a positive type or a negative type.

Next, the photoresist layer 20a is exposed and developed in accordance with a predetermined pattern. Thereby, as shown in FIG. 2 (b), the photoresist layer 20 a is removed in the area where the light transmitting portion 12 is formed, and the photoresist pattern 20 remaining in the photoresist layer 20 a is formed in the area where the light shielding portion 15 is formed. The exposure processing may be performed by direct drawing using, for example, a laser drawing device, or by exposing the original mask having a pattern to be formed. It may be performed by irradiating light.

Then, by using the formed photoresist pattern 20 as a mask, the light-shielding film forming layer 16a is etched, and as shown in FIG. 2 (c), a patterned light-shielding film 16 is formed in a region where the light-shielding portion 15 is formed.

Furthermore, the light-transmitting substrate 11 is etched, for example, by using the formed photoresist pattern 20 and the pattern of the light-shielding film 16 as a mask. As shown in FIG. 2 (d), the light-transmitting substrate 11 is formed to transmit light. The area of the portion 12 forms a recessed portion 11 a of a predetermined depth.

The light-shielding film formation layer 16a and the light-transmitting substrate 11 may be etched by wet etching using a chemical solution, or by plasma dry etching using reactive ion etching (RIE) using a reactive gas. It may be performed, but from the viewpoint of having anisotropy and suppressing side etching (side etching), it is preferable to perform plasma dry etching. Here, as long as the side etching (side etching) at the time of the etching process of the light-transmitting substrate 11 is less than 1/2 of the thickness of the light-shielding film 16, damage to the light-shielding film 16 can be avoided, and the accuracy of the pattern can be reduced.

The concave portion 11 a may be formed by cutting the light-transmitting substrate 11.

Thereafter, by removing the photoresist pattern 20, a mask 10a shown in FIG. 1 (a) can be obtained.

Furthermore, to explain a method for manufacturing the mask 10b shown in FIG. 1 (b), first, a mask base is formed on the entire surface of the light-transmitting substrate 11 to form, for example, a lower light-shielding film forming layer 17a caused by a metal film. As shown in FIG. 3 (a), the material is a mask substrate (the lower light-shielding film forming layer 17a) On the surface, a photoresist is applied to form a photoresist layer 20a. Then, by exposing and developing the photoresist layer 20a in accordance with a predetermined pattern, as shown in FIG. 3 (b), the photoresist layer 20a is removed in a region where the light transmitting portion 12 is formed, and is formed in a region where the light shielding portion 15 is formed. Photoresist pattern 20 remaining in photoresist layer 20a.

Next, by using the formed photoresist pattern 20 as a mask, the lower light-shielding film forming layer 17a is etched. As shown in FIG. 3 (c), a patterned lower light-shielding film is formed in the area where the light-shielding portion 15 is formed. 17.

After removing the photoresist pattern 20, a mask 10b as shown in FIG. 1 (b) can be obtained by forming an upper-layer light-shielding film 18 on the pattern of the lower-layer light-shielding film 17. Here, the upper-layer light-shielding film 18 can be formed by, for example, electroless plating.

Based on the above, in the mask used in the surface treatment method of the present invention, a protective film such as an oxide film may be formed on the surface of the light-shielding film without affecting the level of pattern accuracy. The thickness of the protective film may be a size that does not affect the accuracy of the pattern, for example, 0.05 to 0.5 μm.

Hereinafter, a specific example of a surface treatment apparatus that executes the surface treatment method of the present invention will be described.

Fig. 4 is a cross-sectional view for explaining the structure of an example of the surface treatment apparatus of the present invention. FIG. 5 is an enlarged view showing a part of the surface treatment apparatus shown in FIG. 4.

This surface treatment apparatus is provided with a substrate material (hereinafter, also referred to as a "to-be-processed substrate") as a processing object. A processing chamber 30 is disposed inside, and an excimer lamp 40 as a vacuum ultraviolet light source is disposed inside.的 灯 室 35。 The lamp room 35.

The processing chamber 30 is provided with an opening portion opened in an upward direction. The frame body 31 is provided so that a flat window member 38 may hermetically seal the opening.

As the material constituting the window member 38, any material that transmits vacuum ultraviolet light from the excimer lamp 40 may be used. Examples of the material constituting the light-transmitting substrate 11 of the above-mentioned masks 10a and 10b can be used.

The mask is held by a mask holding mechanism 45 provided in the housing 31 in a state where the surface on which the light shielding film 16 is formed and the surface of the substrate W to be processed face each other. In this example, for example, the mask 10a shown in FIG. 1 (a) is used, but the mask 10b shown in FIG. 1 (b) may be used. The space between the window member 38 and the cover 10a is set to an inert gas atmosphere such as nitrogen.

The mask holding mechanism 45 is a mask stage provided with vacuum chucks that have both ends in the longitudinal direction of the excimer lamp 40 that respectively hold the upper surface of the mask 10a (the back surface of the light-transmitting substrate 11) by vacuum suction. 46.

In addition, a pair of side walls facing each other of the frame body 31 form an air inlet 32 and an air outlet 33 for replacing the inside of the processing chamber 30 with an atmosphere in which oxygen exists. 32a and 32b are opened and closed and connected to the air inlet The flow path on-off valve of the flow path of the piping of 32 and the exhaust port 33.

Inside the housing 31, a work table 50 having a processing object mounting surface 50a formed by a horizontal flat surface is arranged. The workpiece stage 50 is provided with a processing object holding mechanism (not shown) that holds a processing substrate W mounted on the processing object mounting surface 50 a by, for example, vacuum suction.

The work stage 50 is configured to be rotatable in the XYZ θ direction (a plane direction, a height direction of the processing object mounting surface 50a, and an axis perpendicular to the processing object mounting surface 50a by the platform moving mechanism 55). Direction).

The lamp chamber 35 is a box-shaped case 36 having a slightly rectangular shape opened in the downward direction, and is configured in a state where the open end surface thereof abuts the upper surface of the upper wall of the frame 31 constituting the processing chamber 30. Thereby, the opening part of the casing 36 is air-tightly closed, and the internal space which is air-tightly separated from the internal space of the processing chamber 30 by the window member 38 is formed.

The case 36 is provided with an inert gas cleaning means (not shown) for cleaning the inside of the lamp chamber 35 with an inert gas such as nitrogen.

In the lamp room 35, the rod-shaped excimer lamp 40 is arranged in a state where the central axis of the lamp tube extends horizontally. Here, the number of excimer lamps 40 is not particularly limited, and can be appropriately set according to the purpose. When using a plurality of excimer lamps, each excimer lamp is set in a state where the central axis of the lamp tube is located on the same horizontal plane parallel to the object mounting surface 50 a of the workpiece stage 50 and extends parallel to each other. structure.

In the aforementioned surface processing apparatus, the surface processing of the substrate W to be processed is performed as described below.

First, the mask 10 a is held by the mask holding mechanism 45, and the processing substrate W is placed on the processing object mounting surface 50 a of the workpiece stage 50 and held by the processing object holding mechanism. After that, the air in the processing chamber 30 is exhausted, and clean air is supplied into the processing chamber 30 to replace the atmosphere in the processing chamber 30 with an atmosphere in which oxygen exists. Next, by using After the workpiece stage 50 is moved in the XYθ direction and the substrate W to be processed is positioned with respect to the mask 10a, the worktable 50 is raised by the stage moving mechanism 55, so that the surface of the substrate W to be processed contacts the mask 10a in a tight state, for example. . At this time, it is preferable that the pressure of the space between the window member 38 and the cover 10a be higher than the pressure in the processing chamber 30, and the pressure is adjusted as necessary. By performing such pressure adjustment, the pressing force caused by the pressure difference between the pressure in the space between the window member 38 and the mask 10a and the pressure in the processing chamber 30 can lift the mask 10a and the substrate W to be processed. Of tightness. The pressure adjustment can be performed by adjusting the supply amount of the inert gas in the space between the window member 38 and the cover 10 a and the supply amount of the clean air in the processing chamber 30.

In this state, the ultraviolet light is irradiated from the excimer lamp 40 through the mask 10a to the substrate W to be processed, and fine surface selective surface modification of the surface of the substrate W to be processed is performed. Treatment for improving wettability due to decomposition and removal (cleaning) of contaminants such as organic matter on the surface of the processing substrate W.

The illuminance of the vacuum ultraviolet light irradiated to the processing target substrate W is, for example, 1 to 100 mW / cm ² . The irradiation time of the vacuum ultraviolet light is appropriately set according to the purpose, for example, 5 to 2000 seconds.

Then, the mask 10a (10b) used in the surface treatment device of the present invention is formed on the surface level of the patterned light-shielding portion 15 formed on the surface of the flat plate-shaped light-transmitting substrate 11 and exposes light. The difference in the surface level of the light transmitting portion 12 formed on the surface of the transmissive substrate 11 is relatively large. Specifically, in the mask 10a, a light-transmitting substrate is used. The thickness of the area where the light-transmitting portion 12 is formed in 11 is smaller than the thickness t2 of the area where the light-shielding portion 15 is formed, and the difference between the surface level of the light-shielding portion 15 and the surface level of the light-transmitting portion 12 is 1 μm or more. Moreover, in the mask 10b, since the thickness of the light shielding film 16 itself is large, the difference between the surface level of the light shielding portion 15 and the surface level of the light transmitting portion 12 is 1 μm or more. Therefore, it is possible to ensure the amount of oxygen existing in the space partitioned by the adjacent light shielding portions 15 and generating active oxygen or ozone as active seed source by vacuum ultraviolet light. Therefore, even when the mask 10a (10b) is used in close contact with the substrate W to be processed, the situation where the active seed source is depleted can be avoided. Therefore, according to the surface treatment method and the surface treatment device using such a mask 10a (10b), the active oxygen or ozone generated by the vacuum ultraviolet light can indeed contribute to the processing of the substrate W to be processed, and thus can be efficient. The desired processing for the substrate W to be processed is performed.

In addition, since the mask 10a (10b) can be used in close contact with the substrate W to be processed, the pattern of the mask can be faithfully exposed (ultraviolet light irradiation), and high resolution can be obtained.

In addition, since the thickness of the light-transmitting substrate 11 constituting the mask 10a (10b) can be reduced, the vacuum ultraviolet light from the excimer lamp 40 can be efficiently transmitted, and the processing efficiency can be improved. Furthermore, it becomes possible to use a large-sized mask, which improves productivity.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, Various changes can be added.

For example, in the foregoing embodiment, it is assumed that the plugging processing chamber 30 is provided. The structure of the window member 38 in the opening portion of the frame body 31 may be a structure in which the cover 10 a (10 b) is provided so as to hermetically seal the opening portion of the frame body 31 as shown in FIG. 6. In the surface processing device having such a structure, the distance from the excimer lamp 40 as the vacuum ultraviolet light source to the substrate W to be processed is reduced, and a situation where the irradiation intensity of the vacuum ultraviolet light is reduced can be avoided.

As another example, the mask may be spaced from the processing substrate W. When the interval is about 10 μm, it is preferable not to exhaust the air in the processing chamber 30 and supply the air in the processing chamber 30 when the vacuum ultraviolet light is irradiated. This reason is because when the exhaust of the air in the processing chamber 30 and the supply of the air in the processing chamber 30 are continued, processing unevenness occurs.

That is, in the vicinity of the suction port 32, oxygen is changed to ozone or active oxygen, and the surface modification treatment of the substrate W to be processed is effectively performed. However, as it flows down to the exhaust port 33, the concentration of the gas generated by the reaction such as carbon dioxide gas and water vapor generated by the surface modification treatment of the substrate W to be processed becomes higher. As a result, the amounts of ozone and active oxygen are insufficient in the vicinity of the exhaust port 33, so that the processing efficiency is reduced, and processing unevenness occurs.

In the surface treatment device of the present invention, a structure may be provided in which a reflector is provided on the back side of the excimer lamp as a vacuum ultraviolet light source to irradiate the vacuum ultraviolet light emitted from the excimer lamp as slightly parallel light. . With this structure, the illuminance of vacuum ultraviolet light can be increased.

Moreover, in the surface processing apparatus of this invention, you may provide the shutter mechanism which controls irradiation of a vacuum ultraviolet light to a to-be-processed substrate. Excimer lamps are those that are turned on instantaneously to achieve a stable amount of light. However, in this structure, when the substrate to be processed is processed, the excimer lamp is first turned on to make the irradiation reach The amount of vacuum ultraviolet light of the substrate to be processed is more stable.

Hereinafter, specific examples of the present invention will be described, but the present invention is not limited to these.

[Example] [Mask production example A1]

Prepared on the entire surface of a light-transmitting substrate made of synthetic quartz glass with a thickness of 1.5 mm to form a light-shielding film-forming layer (thickness) formed of a laminated film of a chromium film having a thickness of 0.08 μm and a chromium oxide film having a thickness of 0.92 μm 0.1 μm) of a masking material (blank sheet), and a positive-type photoresist (AZP1350) was coated on the light-shielding film forming layer of the masking material to a thickness of 0.5 μm to form a photoresist layer. Next, a laser drawing device ("DWL66FS" manufactured by Japan Laser Corporation) was used to selectively expose an area of 30 mm x 30 mm in the central portion of the photoresist layer to form a circular hole pattern with a diameter of 20 mm, using a developing solution. ("NMD3" manufactured by Tokyo Chemical Industry Co., Ltd.), developing the remaining photoresist layer to form a photoresist pattern. Next, by using the obtained photoresist pattern as a mask for etching, the light-shielding film-forming layer is selectively etched to form (pattern) a patterned light-shielding film. Here, for the etching of the light-shielding film-forming layer, a mixed solution of an aqueous solution of cerium ammonium nitrate and perchloric acid was used.

Next, by using the photoresist pattern and the pattern of the light-shielding film as an etching mask, the area where the light-transmitting portion of the light-transmitting substrate is formed is selectively etched to form a recessed portion having a depth of 1 μm. Here, a 30% by weight hydrofluoric acid was used for etching the light-transmitting substrate.

After that, the remaining photoresist pattern is peeled off with a mixed acid of sulfuric acid and hydrogen peroxide water to produce a mask having a structure shown in FIG. 1 (a) (hereinafter referred to as "mask A1"). The difference between the surface level of the light transmitting portion of the mask A1 and the surface level of the light shielding portion was 1.1 μm.

[Mask creation examples A2 to A7]

In the production example A1 of the aforementioned mask, the depth (etching amount) of the recessed portions was 5 μm, 10 μm, 50 μm, 100 μm, etc., by appropriately changing the processing time (immersion time with the etching solution) during the etching of the light-transmitting substrate. 500 μm and 1000 μm masks (hereinafter referred to as “mask A2” to “mask A7”). The difference between the surface level of the light transmitting portion of the mask A2 to the mask A7 and the surface level of the light shielding portion are 5.1 μm, 10.1 μm, 50.1 μm, 100.1 μm, 500.1 μm, and 1000.1 μm, respectively.

[Mask production example A8]

A comparative mask (hereinafter referred to as "mask A8") was produced by the same method as in the above-mentioned mask production example A1 except that the light-transmitting substrate was not etched (the recess was not formed). The difference between the surface level of the light transmitting portion of the mask A8 and the surface level of the light shielding portion was 0.1 μm (thickness of the light shielding film).

[Mask example B1]

A masking substrate was obtained by forming a lower light-shielding film layer formed of a 0.1 μm-thick nickel film on the entire surface of a light-transmitting substrate made of quartz glass having a thickness of 1.5 mm using a sputtering device. On the mask substrate A photoresist is coated on the lower-layer light-shielding film forming layer to form a photoresist layer. Next, exposure drawing is selectively performed by a laser drawing device ("DWL66FS" manufactured by Japan Laser Corporation), and then developed using a developing solution ("NMD3" manufactured by Tokyo Chemical Industry Co., Ltd.) to form a photoresist pattern. Next, by using the obtained photoresist pattern as a mask for etching, the lower light-shielding film forming layer is selectively etched to form (patterned) a patterned lower light-shielding film. Here, for the etching of the lower light-shielding film-forming layer, a mixed solution of an aqueous solution of cerium ammonium nitrate and perchloric acid was used.

Next, by using a mixed acid of sulfuric acid and hydrogen peroxide water to strip the remaining photoresist pattern, as a plating solution, "LECTROLESS FX-5" (manufactured by Tanaka Precious Metals Industry Co., Ltd.) was used in the lower layer. On the pattern of the light-shielding film, an upper-layer light-shielding film formed of a gold plating film having a thickness of 50 μm was formed, and a mask having a structure shown in FIG. 1 (b) (hereinafter referred to as “mask B1”) was produced.

The difference between the surface level of the light-transmitting portion of the mask B1 and the surface level of the light-shielding portion was 50.1 μm.

The dimensions (vertical × horizontal) of each of the masks A1 to A8 and B1 obtained as described above are 75.8 mm × 75.8 mm.

[Substrate for Test]

As the substrate to be treated for the test, it is used on the entire surface of the base material made of alkali-free glass to form a film with a thickness of 1 to 3 μm from n-Octadecylphosphonic acid or perfluorooctyl phosphonic. acid) organic monomolecular film (SAM). Test quilt The size (length × width) of the processing substrate was 75 mm × 75 mm.

<Example 1>

Referring to the structure shown in FIG. 4, a surface treatment apparatus including a xenon excimer lamp was produced.

Xenon excimer lamp is a so-called double tube structure. The outer diameter of the outer tube of the arc tube is Φ25mm, the thickness is 1mm, the outer diameter of the inner tube is Φ14mm, the thickness is 1mm. The power is 20W.

Further, on the back side of the xenon excimer lamp, a reflecting mirror irradiated with vacuum ultraviolet light emitted from the xenon excimer lamp as parallel light is irradiated to the substrate to be processed.

The size of the opening of the frame constituting the processing chamber is about 100 mm × 100 mm.

The interior space of the lamp room and between the window member and the cover were purged with nitrogen and set to an inert gas atmosphere.

Using each of the masks A1 to A8 produced as described above, when the xenon excimer lamp is lit under the condition that the illuminance of the light exit surface of the window member is 12 mW / cm ² , the hydrophilization of the surface of the substrate to be tested is measured. Time (processing time). Here, the "time required for hydrophilization" refers to the time until the contact angle of water droplets on the surface of the pattern-forming substrate becomes 10 ° or less, and the measurement method of the contact angle is in accordance with JIS R3257 "Test method for wettability of the glass surface of the substrate"". The contact angle at the initial stage (before ultraviolet light irradiation) of the substrate to be processed for the test was about 105 °.

Then, the processing time when the depth of the recessed portion of the mask (the difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion) was changed was evaluated. The results are disclosed in FIG. 7. The "processing time" on the vertical axis in FIG. 7 is a relative value when the processing time when the mask A8 is used is 1.0.

Based on the above results, it was confirmed that a mask can be formed in a region where the light-transmitting portion is formed on the light-transmitting substrate, and a mask having a difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion of 1 μm or more can be confirmed. To reduce processing time. This reason is presumed that even when the mask is used in close contact with the substrate to be processed, the amount of oxygen existing in the space between the adjacent light-shielding portions increases, so that active oxygen and ozone can be surely generated, and the Active oxygen and ozone contribute to the surface treatment of the substrate to be processed.

The effect can be obtained even if the difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion is about 1000 μm. This reason is presumed that although the amount of light reaching due to the absorption of oxygen is reduced, the number of molecules of oxygen in the space between the surface of the light transmitting portion and the surface of the SAM is sufficiently larger than the number of molecules of the organic molecules constituting the SAM. Even if a decomposition reaction occurs, the density of oxygen molecules will not change much, and organic molecules can be decomposed at a certain reaction rate. However, the accuracy of the etching of the light-transmitting portion and the accuracy of the lamination of the light-shielding portion deteriorate, which is not suitable for patterning with high accuracy of the line and space (L / S).

Further, it was confirmed that if the difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion is less than 1 μm, it is difficult to obtain the effect at a sufficient speed. This reason is presumably that as time passes, the density of oxygen molecules in the space between the surface of the light transmitting portion and the surface of the SAM decreases, and the decomposition reaction rate decreases.

Furthermore, using the mask B1 produced in the above, and Evaluation of the processing time was performed in the same manner as in Example 1. As a result, it was confirmed that even when a mask having a thickness of the light-shielding film itself, the difference between the surface level of the light-transmitting portion and the surface level of the light-shielding portion was set to 1 μm or more. In this case, the same effect can be obtained.

10a‧‧‧Mask

10b‧‧‧Mask

11‧‧‧light transmitting substrate

11a‧‧‧ convex

12‧‧‧Transmission Department

15‧‧‧Shading Department

16‧‧‧Light-shielding film

17‧‧‧ lower light-shielding film

18‧‧‧ Upper layer light-shielding film

Claims (5)

A surface treatment method is to form a mask of a patterned light-shielding portion through the surface of a light-transmitting substrate in the presence of oxygen, and irradiate vacuum ultraviolet light to a treatment object, thereby applying a surface to the treatment object. A surface treatment method for forming a specific surface modified region is characterized in that, as the mask, a thickness of a region where the light-transmitting portion is formed using the light-transmitting substrate is smaller than a thickness of a region where the light-shielding portion is formed. A surface treatment method is to form a mask of a patterned light-shielding portion through the surface of a light-transmitting substrate in the presence of oxygen, and irradiate vacuum ultraviolet light to a treatment object, thereby applying a surface to the treatment object. The method for forming a specific surface-modified region is characterized in that, as the mask, a surface level of a light-shielding portion is used, and a difference between a surface level of a light-transmitting portion adjacent to the light-shielding portion is 1 μm or more. A mask is a mask for forming a patterned light-shielding portion on a surface of a light-transmitting substrate, characterized in that the thickness of a region where the light-transmitting portion of the light-transmitting substrate is formed is smaller than that of the region where the light-shielding portion is formed. thickness. A mask is a mask formed on the surface of a light-transmitting substrate to form a patterned light-shielding portion, wherein the surface level of the light-shielding portion is different from the surface level of the light-transmitting portion adjacent to the light-shielding portion. It is 1 μm or more. A surface treatment device comprising: a work table, which is arranged in a processing chamber in an atmosphere where oxygen is present; and Has a flat object mounting surface; a vacuum ultraviolet light source is disposed in a space separated from the internal space of the processing chamber, and transmits vacuum ultraviolet light through a mask to illuminate the object on the workpiece table; and The mask holding mechanism is to hold the mask; the aforementioned vacuum ultraviolet light source is an excimer lamp; the aforementioned mask is the mask described in the patent application scope item 3 or item 4, and the surface forming the light shielding part and the workpiece table In the state where the object to be processed is placed facing, it is held by the aforementioned mask holding mechanism.