TW202105795A - Mask blank, halftone mask, manufacturing method and manufacturing apparatus comprising a drug-resistant layer and an optical characteristic layer - Google Patents

Abstract

A mask blank of the present invention comprises: a transparent substrate; a halftone layer mainly composed of Cr stacked on the surface of the transparent substrate; an etching stop layer stacked on the halftone layer; and a light shielding layer composed mainly of Cr stacked on the etching stop layer. The halftone layer comprises: a drug-resistant layer in which a composition ratio of oxygen is higher than a composition ratio of chromium and nitrogen at an outermost position in a thickness direction, and an optical characteristic layer that secures optical properties having a composition ratio of oxygen lower than the composition ratio of chromium and nitrogen at a position close to the transparent substrate in a thickness direction.

Description

Mask substrate, semi-dimmer mask, manufacturing method, and manufacturing device

The present invention relates to a preferred technology for a photomask substrate, a semi-dimmer mask, a manufacturing method, and a manufacturing device.

Substrates for FPD (flat panel displays) such as liquid crystal displays or organic EL (Electroluminescence) displays are manufactured by using a plurality of photomasks. In order to reduce the number of manufacturing steps, the number of mask sheets can be reduced by using a semi-transmissive half-dimmer mask.

Furthermore, in color filters or organic EL displays, the shape of the organic resin can be controlled by exposing and developing the photosensitive organic resin using a semi-transmissive mask, so that spacers or openings of suitable shapes can be formed. Therefore, the importance of the half-dimmer mask has increased (Patent Document 1, etc.).

These half-tone masks are formed by using a light-shielding layer and a half-tone layer (semi-transmissive layer). As the structure of the semi-dimmer cover, there are known structures in which a semi-transmissive layer is formed on the light-shielding layer (upper structure, upper type), and a structure in which the semi-transmissive layer is formed under the light-shielding layer (lower structure, lower type). 2 kinds of structures. After forming the laminated film of the half-tone layer and the light-shielding layer, the half-dimmer mask of the lower structure can be exposed, developed, and etched to each film in a desired pattern to complete the photomask. Therefore, the semi-dimmer mask with the lower structure has the advantage of being able to form the mask in a short period of time.

As the material of the light-shielding layer of the FPD mask, Cr is generally used, and as the material of the half-tone layer, it is also desirable to use Cr. Cr exhibits excellent liquid resistance, and the processing method to become a photomask has also been established. Furthermore, it also has the advantage that the wavelength dependence of transmittance can be reduced by using Cr to form a half-tone layer.

In addition, when Cr is used to form the light-shielding layer and the half-tone layer, in order to form a desired pattern, etching is performed with a Cr etchant. At this time, in order to form a region where the light-shielding layer and the half-tone layer are not provided, a photoresist layer is laminated on the light-shielding layer or the half-tone layer. The photoresist layer will be removed after patterning. In this way, in order to remove the photoresist layer or maintain the surface state, in the mask manufacturing step, in order to clean the light shielding layer and/or the semi-tone layer, a cleaning step using sulfuric acid, sulfuric acid hydrogen peroxide mixture or ozone is required respectively.

[Prior Technical Literature] [Patent Literature] [0007] [Patent Document 1] Japanese Patent Laid-Open No. 2006-106575

[The problem to be solved by the invention]

However, in the case of the semi-tone layer using Cr material, under the condition that the wavelength dependence of the transmittance is small, the cleaning step using sulfuric acid or ozone used in the mask manufacturing step causes the half-tone layer to suffer Etching. At this point, it is understood that there will be a problem of the transmittance change of the halftone layer.

In particular, when patterning the light-shielding layer after patterning the half-tone layer, the etching time becomes longer, so there is a problem that the transmittance change of the half-tone layer becomes larger.

In order to solve this problem, the transmittance change caused by washing is taken into consideration, and the transmittance of the semi-toned layer obtained by initial film formation is set to be low. On this basis, sulfuric acid or ozone can also be used for washing.

However, in this case, if the transmittance change in the washing step is too large, the difference in the transmittance change in the washing step will also become larger. Therefore, in this case, it is also understood that it is difficult to control the transmittance, which is an important characteristic of the half-dimmer mask, to a desired value.

The present invention has been completed in view of the above circumstances, and it is desired to achieve the following objects. 1. In the cleaning step using a mixture of sulfuric acid, hydrogen peroxide or ozone, the drug resistance characteristics with little change in optical characteristics are also obtained. 2. Inhibit the change of transmittance in the washing step. 3. Reduce the wavelength dependence of transmittance. 4. It is possible to provide half-dimmer masks that meet the requirements of 1 to 3 above at the same time. 5. Reduce the wavelength dependence of transmittance. [Technical means to solve the problem]

After intensive research, the inventors have learned that by controlling the composition of oxygen, nitrogen, and chromium in the semi-toned layer formed by using Cr materials, it is possible to obtain a small transmittance change in the cleaning step using sulfuric acid or ozone. Resistance characteristics. Furthermore, it is found that in the half-tone layer, by increasing the oxygen concentration especially on the surface, the drug resistance characteristics can be improved. However, if the oxygen concentration is increased, the wavelength dependence of the transmittance becomes greater. Furthermore, if the oxygen concentration becomes If it is too high, on the contrary, chemical resistance properties will decrease. Corresponding to this, it is known that by appropriately controlling the composition in the depth direction of the half-tone layer, the chemical resistance is higher at the time, and the wavelength dependence of the transmittance of the half-tone layer is smaller. Furthermore, it is known that by controlling the sheet resistance of the half-tone layer, the wavelength dependence of the transmittance can also be suppressed.

The photomask base in one aspect of the present invention includes: a transparent substrate; a half-tone layer laminated on the surface of the transparent substrate and containing Cr as the main component; an etching stop layer laminated on the above-mentioned half-tone layer; and light shielding Layer, which is laminated on the above-mentioned etching stop layer and is mainly composed of Cr; and the most surface position of the above-mentioned half-tone layer in the thickness direction has a chemical resistance that the composition ratio of oxygen is higher than the composition ratio of chromium and nitrogen The layer, at a position close to the above-mentioned transparent substrate in the thickness direction, has an optical characteristic layer with a composition ratio of oxygen lower than that of chromium and nitrogen and ensuring optical characteristics; thereby, the above-mentioned problem is solved. The mask base in one aspect of the present invention includes: a transparent substrate; a light-shielding layer laminated on the surface of the transparent substrate and containing Cr as the main component; and a half-tone layer laminated on the light-shielding layer and containing Cr Main component; and the most surface position of the semitone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen, which is adjacent to the transparent substrate in the thickness direction The position has an optical characteristic layer that has a composition ratio of oxygen lower than that of chromium and nitrogen and ensures optical characteristics; thereby, the above-mentioned problem is solved. The photomask base in one aspect of the present invention may be: in the above-mentioned halftone layer, the composition ratio of oxygen decreases from the most surface position in the thickness direction toward the position close to the above-mentioned transparent substrate. The photomask substrate in one aspect of the present invention may be: in the halftone layer, the composition ratio of oxygen in the drug-resistant layer is set to be greater than 4 times the composition ratio of the smallest oxygen in the optical characteristic layer. The photomask substrate in one aspect of the present invention may be: in the above-mentioned half-tone layer, the sheet resistance is set to 1.3×10 ³ Ω/sq or less. The manufacturing method of the photomask substrate in one aspect of the present invention may be: it is a method for manufacturing the photomask substrate as described in any one of the above, and has: a film forming step in which the laminated layer is mainly composed of Cr The original half-tone layer; and an oxidation treatment step, which oxidizes the original half-tone layer formed in the above-mentioned film forming step to make it into the above-mentioned half-tone layer. The manufacturing method of the photomask substrate in one aspect of the present invention may be: in the oxidation treatment step, the oxidation treatment of the original half-tone layer is performed by the excited oxidation treatment gas. The manufacturing method of the photomask substrate in one aspect of the present invention may be that the oxidation treatment gas in the oxidation treatment step is nitrogen oxide. The manufacturing method of the photomask substrate in one aspect of the present invention may be: it is a method for manufacturing the photomask substrate as described in any one of the above, and has the film formation of the above-mentioned semitone layer with the main component of Cr being laminated step. The manufacturing method of the semi-dimmer mask in one aspect of the present invention may be: it is a method of manufacturing a semi-dimmer mask using the mask substrate as described in any one of the above, and has: The step of patterning the above-mentioned half-tone layer by the mask; and the cleaning step of removing the above-mentioned photomask. The manufacturing method of the semi-dimmer mask in one aspect of the present invention may be: in the above-mentioned washing step, a mixture of sulfuric acid and hydrogen peroxide or ozone water is used as the washing liquid. The half-dimmer cover in one aspect of the present invention may be manufactured by the above-mentioned method for manufacturing the half-dimmer cover. The manufacturing apparatus of the photomask substrate in one aspect of the present invention may be: it is used in the manufacturing method of the photomask substrate as described in any one of the above, and has: a film forming section which forms the original halftone layer And an oxidation treatment part, which oxidizes the original half-tone layer; and the oxidation treatment part is provided with an excitation gas supply part capable of exciting and supplying an oxidation treatment gas. The manufacturing apparatus of the photomask substrate in one aspect of the present invention may be: it is used in the manufacturing method of the photomask substrate, and has a film forming part for forming the semitone layer, and the film forming part is provided with an excitable And the excitation gas supply part that supplies the oxidation treatment gas.

A photomask base of one aspect of the present invention includes: a transparent substrate; a half-tone layer laminated on the surface of the transparent substrate and containing Cr as the main component; an etching stop layer laminated on the above-mentioned half-tone layer; and a light-shielding layer , It is laminated on the above-mentioned etch stop layer with Cr as the main component; and the most surface position of the above-mentioned half-tone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen , At the position close to the transparent substrate in the thickness direction, the composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen and has an optical characteristic layer that ensures optical characteristics; thereby, the above problem is solved. One aspect of the photomask base of the present invention may be that in the above-mentioned halftone layer, the composition ratio of oxygen decreases from the most surface position in the thickness direction toward the position close to the above-mentioned transparent substrate. In the photomask substrate of one aspect of the present invention, it is preferable that: in the halftone layer, the composition ratio of oxygen in the drug-resistant layer is set to be greater than the composition ratio of the smallest oxygen in the optical characteristic layer. Times. In addition, the manufacturing method of the photomask substrate of one aspect of the present invention may also be: it is the manufacturing method of the photomask substrate as described in any one of the above, and has: a film forming step, which is laminated on the transparent substrate The original half-tone layer mainly composed of Cr; and an oxidation treatment step, which oxidizes the original half-tone layer formed in the above-mentioned film forming step to make it into the above-mentioned half-tone layer. One aspect of the manufacturing method of the photomask substrate of the present invention may be: in the oxidation treatment step, the oxidation treatment of the original half-tone layer is performed by the excited oxidation treatment gas. One aspect of the manufacturing method of the photomask substrate of the present invention may be that the oxidation treatment gas in the oxidation treatment step is nitrogen oxide. In addition, a method for manufacturing a photomask substrate according to one aspect of the present invention may be: it is the method for manufacturing a photomask substrate as described in any one of the above, and has the above-mentioned half layered with Cr as the main component on the above-mentioned transparent substrate. The film-forming step of the adjustment layer. In one aspect of the manufacturing method of the photomask substrate of the present invention, it may include a step of laminating the above-mentioned etching stop layer and a step of laminating the above-mentioned light-shielding layer. In addition, the method for manufacturing a half-dimmer mask of one aspect of the present invention is preferably: it is a method of manufacturing a half-dimmer mask using a mask substrate manufactured by the above-mentioned manufacturing method, and has: The step of patterning the half-tone layer with the patterned mask; and the cleaning step of removing the mask. In the manufacturing method of the semi-dimmer mask of one aspect of the present invention, it may be: in the above-mentioned cleaning step, a sulfuric acid hydrogen peroxide mixture or ozone water is used as a cleaning liquid. The half-dimmer cover of one aspect of the present invention may be manufactured by the above-mentioned manufacturing method. In the manufacturing apparatus of a photomask base of one aspect of the present invention, it may be used in the manufacturing method of a photomask base as described in any one of the above, and has: a film forming part which is formed on the transparent substrate. Film the original half-tone layer; and an oxidation treatment part for oxidizing the original half-tone layer; and the oxidation treatment part is provided with an excitation gas supply part capable of exciting and supplying the oxidation treatment gas. In the manufacturing apparatus of a photomask substrate of one aspect of the present invention, it can be used in the manufacturing method of the photomask substrate, and has a film forming part for forming the semitone layer on the transparent substrate, and The film forming part is provided with an excitation gas supply part capable of exciting and supplying an oxidation treatment gas.

A photomask base of one aspect of the present invention includes: a transparent substrate; a half-tone layer laminated on the surface of the transparent substrate and containing Cr as the main component; an etching stop layer laminated on the above-mentioned half-tone layer; and a light-shielding layer , It is laminated on the above-mentioned etch stop layer with Cr as the main component; and the most surface position of the above-mentioned half-tone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen , At the position close to the above-mentioned transparent substrate in the thickness direction, the composition ratio of oxygen is lower than the composition ratio of chromium to nitrogen and has an optical characteristic layer that ensures optical characteristics. As a result, as a bottom-mounted semi-dimmer mask, the drug-resistant layer is formed such that the composition ratio of oxygen is higher than the composition ratio of chromium to nitrogen, so that the drug-resistant layer can be used to maintain the resistance during the cleaning step of the mask. Medicinal properties. Therefore, it is possible to suppress the change in the optical characteristics of the half-tone layer in the cleaning step, and thus it is possible to suppress the change in the optical characteristics of the half-tone mask manufactured from the mask substrate. At the same time, the optical characteristic layer is formed so that the composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen, whereby the optical characteristic layer can be used to maintain the necessary optics of the half-tone layer as a half-tone mask manufactured from the mask substrate. characteristic.

The mask base in one aspect of the present invention includes: a transparent substrate; a light-shielding layer laminated on the surface of the transparent substrate and containing Cr as the main component; and a half-tone layer laminated on the light-shielding layer and containing Cr Main component; and the most surface position of the semitone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen, which is adjacent to the transparent substrate in the thickness direction The position has an optical characteristic layer that has a composition ratio of oxygen lower than that of chromium and nitrogen and ensures optical characteristics. As a result, as a top-mounted semi-dimmer mask, the drug-resistant layer is formed so that the composition ratio of oxygen is higher than the composition ratio of chromium to nitrogen, so that the drug-resistant layer can be used to maintain the resistance during the cleaning step of the photomask. Medicinal properties. Therefore, it is possible to suppress the change in the optical characteristics of the half-tone layer in the cleaning step, and thus it is possible to suppress the change in the optical characteristics of the half-tone mask manufactured from the mask substrate. At the same time, the optical characteristic layer is formed so that the composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen, whereby the optical characteristic layer can be used to maintain the necessary optics of the half-tone layer as a half-tone mask manufactured from the mask substrate. characteristic.

In one aspect of the present invention, the photomask base is in the above-mentioned half-tone layer, and the composition ratio of oxygen decreases from the most surface position in the thickness direction toward the position close to the above-mentioned transparent substrate. Thereby, it is possible to manufacture a mask substrate with a half-tone layer capable of simultaneously maintaining the drug resistance in the cleaning step and the suppressing effect of the change in optical properties.

In the photomask substrate of one aspect of the present invention, in the halftone layer, the composition ratio of oxygen in the drug-resistant layer is set to be greater than 4 times the composition ratio of the smallest oxygen in the optical characteristic layer. Thereby, it is possible to manufacture a mask substrate with a half-tone layer that can maintain sufficient chemical resistance of the surface of the half-tone layer exposed to the cleaning solution and the second half of the cleaning step accompanying pattern formation. Inhibition of changes in optical properties of the layer.

The photomask substrate in one aspect of the present invention is in the above-mentioned half-tone layer, and the sheet resistance is set to 1.3×10 ³ Ω/sq or less. Accordingly, by setting the sheet resistance, the difference in transmittance caused by the wavelength of the exposure light can be reduced in the half-tone layer. In this way, it is possible to provide a half-dimmer mask that can suppress the occurrence of a difference in transmittance caused by the wavelength of the exposure light, and can easily cope with the exposure light of the composite wavelength.

The manufacturing method of the photomask substrate in one aspect of the present invention is a method for manufacturing the photomask substrate as described in any one of the above, and has: a film forming step, which is a stack of the original semitone layer mainly composed of Cr And an oxidation treatment step, which oxidizes the original half-tone layer formed in the film-forming step to make it the half-tone layer. Thereby, it is possible to use the film forming step to adopt the previously known film forming conditions of the film with Cr as the main component to easily form the original half-tone layer with the desired optical properties. Thereafter, an oxidation treatment step can be used to form a half-tone layer by oxidizing the original half-tone layer. The most surface position of the half-tone layer in the thickness direction has a composition ratio of oxygen higher than that of chromium and nitrogen. The composition ratio of the drug-resistant layer has an optical characteristic layer that has an oxygen composition ratio lower than that of chromium and nitrogen at a position close to the above-mentioned transparent substrate in the thickness direction and ensures optical characteristics. At this time, it is possible to form both a drug-resistant layer with sufficient drug resistance and a half-tone layer that maintains the necessary optical properties as a half-tone mask. Specifically, when a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen can be formed at the most surface position in the thickness direction, a position adjacent to the above-mentioned transparent substrate in the thickness direction can be formed. The composition ratio of the formed oxygen is the same level as that of the original half-tone layer and an optical characteristic layer that ensures optical characteristics. Furthermore, it is possible to provide a semi-dimmer mask which is laminated with such a half-tone layer on the light-shielding layer. Or, it is also possible to provide an etching stop layer and a light shielding layer placed underneath the semi-adjustable mask in order on the half-adjustable layer.

In addition, a method for manufacturing a photomask substrate according to one aspect of the present invention is the method for manufacturing a photomask substrate as described in any one of the above, and has: a film forming step, which is laminated on the transparent substrate with Cr as the main component The original half-tone layer; and an oxidation treatment step, which oxidizes the original half-tone layer formed in the film forming step to make it the half-tone layer. As a result, the film forming step can be used to easily form the original half-tone layer with the desired optical characteristics on the transparent substrate using the previously known film forming conditions of the film with Cr as the main component. Thereafter, an oxidation treatment step can be used to form a half-tone layer by oxidizing the original half-tone layer. The most surface position of the half-tone layer in the thickness direction has a composition ratio of oxygen higher than that of chromium and nitrogen. The composition ratio of the drug-resistant layer has an optical characteristic layer that has an oxygen composition ratio lower than that of chromium and nitrogen at a position close to the above-mentioned transparent substrate in the thickness direction and ensures optical characteristics. At this time, it is possible to form both a drug-resistant layer with sufficient drug resistance and a half-tone layer that maintains the necessary optical properties as a half-tone mask. Specifically, when a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen can be formed at the most surface position in the thickness direction, a position adjacent to the above-mentioned transparent substrate in the thickness direction can be formed. The composition ratio of the formed oxygen is the same level as that of the original half-tone layer and an optical characteristic layer that ensures optical characteristics.

In one aspect of the manufacturing method of the photomask substrate of the present invention, in the oxidation treatment step, the oxidation treatment of the original half-tone layer is performed by the excited oxidation treatment gas. Thereby, when the drug-resistant layer is formed, it is possible to maintain the composition ratio of oxygen at a position close to the transparent substrate in the thickness direction of the original half-tone layer at the same level as that of the original half-tone layer. Therefore, an optical characteristic layer that ensures optical characteristics can be formed.

In one aspect of the manufacturing method of the photomask substrate of the present invention, the oxidation treatment gas in the oxidation treatment step is nitrogen oxide. Thereby, the oxidation state of the original half-tone layer can be controlled to form a drug-resistant layer with sufficient drug resistance, and at this time, the oxygen can be removed from the position close to the transparent substrate in the thickness direction of the original half-tone layer. The composition ratio is controlled to the same level as the original halftone layer. In addition, the above-mentioned photomask substrate can be manufactured only by controlling the atmosphere gas in the oxidation treatment step.

The manufacturing method of the photomask substrate in one aspect of the present invention is a method for manufacturing the photomask substrate as described in any one of the above, and has a film forming step of laminating the above-mentioned semitone layer with Cr as the main component. Thereby, the composition ratio of oxygen can be changed in the thickness direction in the step of forming the semitone layer to form a semitone layer with a drug-resistant layer and an optical characteristic layer. At this time, the above-mentioned photomask substrate can be manufactured only by controlling the atmosphere gas in the film forming step. Furthermore, it is possible to provide a semi-dimmer mask which is laminated with such a half-tone layer on the light-shielding layer. Or, it is also possible to provide an etching stop layer and a light shielding layer placed underneath the semi-adjustable mask in order on the half-adjustable layer.

In addition, a method for manufacturing a photomask substrate according to one aspect of the present invention is the method for manufacturing a photomask substrate as described in any one of the above, and has the structure of laminating the semitone layer mainly composed of Cr on the transparent substrate. Film step. Thereby, the composition ratio of oxygen can be changed in the thickness direction in the step of forming the semitone layer to form a semitone layer with a drug-resistant layer and an optical characteristic layer. At this time, the above-mentioned photomask substrate can be manufactured only by controlling the atmosphere gas in the film forming step.

In one aspect of the manufacturing method of the photomask substrate of the present invention, there is a step of laminating the above-mentioned etching stop layer and a step of laminating the above-mentioned light-shielding layer. Thereby, a half-dimmer mask with sufficient chemical resistance and desired optical characteristics can be manufactured. Here, as an etching stop layer with sufficient selectivity, it exhibits an etching stop capability, and a half-dimmer mask having a desired pattern shape can be manufactured.

In addition, the manufacturing method of a half-dimmer mask of one aspect of the present invention is a method of manufacturing a half-dimmer mask using a mask substrate manufactured by the above-mentioned manufacturing method, and has: The step of patterning the half-tone layer; and the cleaning step of removing the mask. Thereby, it is possible to manufacture a half-tone with a desired pattern and a desired optical characteristic layer by including a mask substrate with a half-tone layer with an optical characteristic layer, and the optical characteristic layer can be kept exposed to the cleaning solution at the same time Sufficient chemical resistance of the surface of the half-tone layer, and suppression of changes in the optical properties of the half-tone layer after the cleaning step accompanying the pattern formation.

In the manufacturing method of the semi-dimmer mask of one aspect of the present invention, in the above-mentioned washing step, a sulfuric acid hydrogen peroxide mixture or ozone water is used as a washing liquid. In the cleaning step, the drug-resistant layer can maintain the state in which the variation of the optical properties is suppressed, and the necessary cleaning can be performed in the cleaning step to remove the foreign matter or the mask on the surface of the half-tone layer.

The half-dimmer mask of one aspect of the present invention is manufactured by the above-mentioned manufacturing method. Thereby, it is possible to manufacture a half-dimmer mask with desired optical characteristics.

One aspect of the manufacturing apparatus of a photomask substrate of the present invention is used in the manufacturing method of a photomask substrate as described in any one of the above, and has: a film forming part for forming a film of the original semitone layer; and an oxidation treatment part , Which performs oxidation treatment on the original half-tone layer; and the oxidation treatment part is provided with an excitation gas supply part capable of exciting and supplying an oxidation treatment gas. Thereby, it is possible to manufacture a photomask base with an optical characteristic layer that can maintain the oxygen composition ratio at a position close to the transparent substrate in the thickness direction of the original half-tone layer when the drug-resistant layer is formed The same level as the original half-tone layer, and to ensure optical characteristics.

One aspect of the manufacturing apparatus of a photomask substrate of the present invention is used in the manufacturing method of a photomask substrate as described in any one of the above, and has: a film forming part for forming the original semitone layer on the transparent substrate; And an oxidation treatment part, which performs oxidation treatment on the original half-tone layer; and the oxidation treatment part is provided with an excitation gas supply part capable of exciting and supplying the oxidation treatment gas. Thereby, it is possible to manufacture a photomask base with an optical characteristic layer that can maintain the oxygen composition ratio at a position close to the transparent substrate in the thickness direction of the original half-tone layer when the drug-resistant layer is formed The same level as the original half-tone layer, and to ensure optical characteristics.

In the manufacturing apparatus of the photomask substrate of one aspect of the present invention, it can be used in the manufacturing method of the photomask substrate, and has a film forming part for forming the semitone layer, and is provided in the film forming part Excitation gas supply part that can excite and supply oxidation treatment gas. Thereby, it is possible to manufacture a photomask base with an optical characteristic layer that can maintain the oxygen composition ratio at a position close to the transparent substrate in the thickness direction of the original half-tone layer when the drug-resistant layer is formed The same level as the original half-tone layer, and to ensure optical characteristics.

In the manufacturing apparatus of a photomask substrate of one aspect of the present invention, it can be used in the manufacturing method of the photomask substrate, and has a film forming part for forming the semitone layer on the transparent substrate, and The film forming part is provided with an excitation gas supply part capable of exciting and supplying an oxidation treatment gas. Thereby, it is possible to manufacture a photomask base with an optical characteristic layer that can maintain the oxygen composition ratio at a position close to the transparent substrate in the thickness direction of the original half-tone layer when the drug-resistant layer is formed The same level as the original half-tone layer, and to ensure optical characteristics. [Effects of Invention]

According to one aspect of the present invention, the following effects can be achieved: it is possible to provide a chemical resistance characteristic that has a small change in optical properties in the cleaning step using a sulfuric acid hydrogen peroxide mixture or ozone, and can inhibit the penetration in the cleaning step It is a half-dimmer mask that can reduce the wavelength dependence of transmittance.

Hereinafter, the photomask base, the semi-dimmer mask, the manufacturing method, and the manufacturing apparatus of the first embodiment of the present invention will be described based on the drawings. FIG. 1 is a cross-sectional view of the mask substrate in this embodiment, and the symbol MB in the figure is the mask substrate.

The mask substrate MB of the present embodiment is used for, for example, a half-dimmer mask used in the range of 365 nm to 436 nm in the wavelength of the exposure light. As shown in FIG. 1, the mask base MB includes a transparent substrate S, a half-tone layer 11 formed on the transparent substrate S, an etching stop layer 12 formed on the half-tone layer 11, and an etching stop layer 12 formed on the The light-shielding layer 13.

As the transparent substrate S, a material excellent in transparency and optical isotropy can be used, for example, a quartz glass substrate can be used. The size of the transparent substrate S is not particularly limited, and is based on the substrate to be exposed using the mask (for example, the substrate used for FPD such as LCD (liquid crystal display), plasma display, organic EL (electroluminescence) display, or semiconductor substrate ) And appropriately selected. In this embodiment, it can be applied to a substrate with a diameter of about 100 mm, or a rectangular substrate with a side of about 50-100 mm to a side of 300 mm or more. Furthermore, it can also be used for a vertical length of 450 mm and a horizontal length of 550 mm, a quartz substrate with a thickness of 8 mm, or a substrate with a maximum side dimension of 1000 mm or more and a thickness of 10 mm or more.

In addition, the surface of the transparent substrate S may be polished to reduce the flatness of the transparent substrate S. The flatness of the transparent substrate S may be 20 μm or less, for example. Thereby, the focal depth of the photomask can be deepened, thereby making a greater contribution to the formation of fine and high-precision patterns. Furthermore, the flatness is preferably as small as 10 μm or less.

The half-tone layer 11 is a layer with Cr as the main component. Specifically, it may be selected from Cr monomer, and Cr oxides, nitrides, carbides, oxynitrides, nitrogen carbides, and carbonitride oxides. 1 composition. In addition, two or more types selected from these materials may be laminated to form the halftone layer 11.

For example, the half-tone layer 11 has a drug-resistant layer 11a in which the composition ratio of oxygen is higher than the composition ratio of chromium to the composition ratio of nitrogen at the position which becomes the outermost surface in the thickness direction. In addition, the half-tone layer 11 has an optical characteristic layer 11b whose composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen at a position adjacent to the transparent substrate S in the thickness direction. In the half-tone layer 11, the optical characteristic layer 11b has the characteristic of being durable as a half-tone mask.

In addition, in the halftone layer 11, in the thickness direction, from the most surface position close to the etching stop layer 12 toward the position close to the transparent substrate S, the composition ratio of oxygen continuously decreases. The slope of the oxygen concentration in the half-tone layer 11 is set to be substantially constant in the thickness direction.

The slope of the oxygen concentration in the half-tone layer 11 gradually decreases in the thickness direction from the most surface position. Therefore, no clear interface is formed between the drug-resistant layer 11a and the optical characteristic layer 11b.

Furthermore, in the vicinity of the most surface position of the half-tone layer 11 and the vicinity of the position adjacent to the transparent substrate S, the composition ratio of oxygen may be disturbed. However, the degree is only a few atm%, which does not pose a problem for the chemical resistance and optical properties of the half-tone layer 11.

In the thickness direction of the halftone layer 11, from the most surface position close to the etching stop layer 12 toward the position close to the transparent substrate S, the composition ratio of nitrogen continuously increases. The slope of the nitrogen concentration in the half-tone layer 11 is set to be substantially constant in the thickness direction.

In the thickness direction of the half-tone layer 11, from the most surface position close to the etching stop layer 12 to the position close to the transparent substrate S, the carbon composition ratio is approximately constant. In the thickness direction of the half-tone layer 11, from the most surface position close to the etching stop layer 12 toward the position close to the transparent substrate S, the carbon composition ratio continuously increases slightly.

In the half-tone layer 11, the composition ratio of the largest oxygen in the drug-resistant layer 11a is set to be greater than 4 times the composition ratio of the smallest oxygen in the optical characteristic layer 11b. In the halftone layer 11, the composition ratio of the largest oxygen in the drug-resistant layer 11a is set to be greater than 5 times the composition ratio of the smallest oxygen in the optical characteristic layer 11b. In the halftone layer 11, the composition ratio of the largest oxygen in the drug-resistant layer 11a is set to be slightly smaller than 6 times the composition ratio of the smallest oxygen in the optical characteristic layer 11b.

The drug-resistant layer 11a, as shown in FIG. 20 below, may be a region where the composition ratio of oxygen in the thickness direction of the half-tone layer 11 is higher than the composition ratio of carbon or the composition ratio of nitrogen. Similarly in the drug-resistant layer 11a, in the thickness direction, from the position of the outermost surface adjacent to the etching stop layer 12 toward the position adjacent to the transparent substrate S, the composition ratio of oxygen decreases.

As an example, as shown in FIG. 20 below, at the topmost surface positions of the half-tone layer 11 and the drug-resistant layer 11a, the composition ratio of oxygen is set to be greater than 60 atm%. Furthermore, at the most surface positions of the halftone layer 11 and the drug-resistant layer 11a, the composition ratio of oxygen is set to be greater than 65 atm%.

In addition, at the most surface positions of the half-tone layer 11 and the drug-resistant layer 11a, the composition ratio of chromium is set to be greater than 20 atm% and less than 30 atm%. Furthermore, at the most surface positions of the halftone layer 11 and the drug-resistant layer 11a, the composition ratio of nitrogen is set to be less than 10 atm%.

In addition, the composition ratio of the smallest oxygen in the optical characteristic layer 11b is set to be less than 15 atm%. The composition ratio of the smallest oxygen in the optical characteristic layer 11b is set to be about 10 atm%. It is not preferable if the composition ratio of the smallest oxygen in the optical characteristic layer 11b is greater than 20 atm%.

The optical characteristic layer 11b may be a region where the composition ratio of oxygen in the thickness direction of the halftone layer 11 is lower than the composition ratio of carbon or the composition ratio of nitrogen, as shown in FIG. 20 below. Similarly in the optical characteristic layer 11b, in the thickness direction, from the position of the drug-resistant layer 11a adjacent to the etching stop layer 12 toward the position adjacent to the transparent substrate S, the composition ratio of oxygen decreases. In addition, the position where the composition ratio of oxygen in the optical characteristic layer 11b is the smallest is set as a position close to the transparent substrate S.

As the etching stop layer 12, a metal silicon compound film containing nitrogen can be cited, for example, containing at least one metal selected from the group consisting of Ni, Co, Fe, Ti, Al, Nb, Mo, W, and Hf, or a combination of these metals Alloy and Si film, especially molybdenum silicon compound film, MoSi _X (X≧2) film (such as MoSi ₂ film, MoSi ₃ film or MoSi ₄ film, etc.).

For example, regarding the composition of the MoSi film, in terms of the composition ratio of Mo to Si, _{the value of X in the MoSi X} film can be within the range of 2.0 to 3.7. Here, if _{the value of X in the MoSi X} film is made smaller within this range, the etching rate can be increased. In addition, if _{the value of X in the MoSi X} film is made larger within this range, the etching rate can be reduced.

The position of the etching stop layer 12 in the thickness direction adjacent to the light shielding layer 13 is provided with a high nitrogen area with a nitrogen concentration set to 30 atm% or more. The etching stop layer 12 is set so that the total film thickness of the high-nitrogen region and the high-nitrogen region closer to the low-nitrogen region of the half-tone layer 11 is 15 nm or more and 40 nm or less.

As the etching stop layer 12, by setting the nitrogen concentration and the composition ratio of Mo and Si as the composition of the MoSi film, the film characteristic of the etching stop layer 12 for etching, that is, the etching rate, can be set.

Thereby, in the etching of the light shielding layer 13 located on the upper side (surface side, outer side) of the etching stop layer 12, the etching stop layer 12 can have a higher selectivity, and the etching rate of the etching stop layer 12 can be reduced. To make the etching stop layer 12 have etching resistance and prevent damage to the half-tone layer 11, the film composition is set.

The light-shielding layer 13 contains Cr as a main component, and specifically contains Cr and nitrogen. Furthermore, the light-shielding layer 13 may have a different composition in the thickness direction. In this case, the light-shielding layer 13 may be selected from Cr monomer, and oxides, nitrides, carbides, oxynitrides, and nitrogen carbides. One type of compound and carbonitride, or a layered structure of two or more types. The light-shielding layer 13 is formed with a thickness (for example, 80 nm to 200 nm) that can obtain specific optical characteristics.

Here, the light-shielding layer 13 and the half-tone layer 11 are both chromium-based thin films and have been oxidized by nitrogen. However, compared with the two, the half-tone layer 11 is set to have a greater degree of oxidation than the light-shielding layer 13 and is difficult to oxidize.

The mask base MB of this embodiment can be used, for example, when manufacturing a half-dimmer mask M, that is, a mask for patterning a glass substrate for FPD.

Fig. 2 is a cross-sectional view showing a half-dimmer mask manufactured from the mask substrate in this embodiment. As shown in FIG. 2, the half-tone mask M of this embodiment has a transmission area M1, a half-tone area M2, and a light-shielding area M3 in the mask base MB.

The transmission area M1 is an area where the glass substrate (transparent substrate) S is exposed. The halftone area M2 is an area where the halftone pattern 11p obtained by patterning only the halftone layer 11 in the mask base MB is formed on the glass substrate (transparent substrate) S.

The light-shielding area M3 is a region where the half-tone layer 11, the etching stop layer 12, and the light-shielding layer 13 in the mask base MB are patterned, and the half-tone pattern 11p, the etching stop pattern 12p, and the light-shielding pattern 13p are laminated.

In the half-tone mask M, the half-tone region M2 is, for example, a region that can make the transmitted light semi-transparent during the exposure process. The light-shielding area M3 is an area through which the irradiated light can not be transmitted by the light-shielding pattern 13p in the exposure process.

For example, according to the half-dimmer mask M, in the exposure process, light in the wavelength region can be used, especially compound wavelength light including g-line (436 nm), h-line (405 nm), and i-line (365 nm) as exposure Light. Thereby, exposure and development can be performed to control the shape of the organic resin, thereby forming spacers or openings of suitable shapes. In addition, the pattern accuracy can be greatly improved, thereby realizing fine and high-precision pattern formation.

According to this half-dimmer mask, the pattern accuracy can be improved by using the light in the above-mentioned wavelength region, so that fine and high-precision pattern formation can be realized. In this way, high-quality flat-panel displays and the like can be manufactured.

Hereinafter, the manufacturing method of the mask base MB of this embodiment is demonstrated.

The mask substrate MB in this embodiment is manufactured by the manufacturing apparatus shown in FIG. 3 or FIG. 4. Fig. 3 is a schematic diagram showing a manufacturing apparatus for manufacturing a photomask substrate in this embodiment.

The manufacturing device S10 shown in FIG. 3 is a reverse sputtering device and a device capable of performing oxidation treatment. The manufacturing apparatus S10 has a loading/unloading chamber S11, a film forming chamber (vacuum processing chamber, film forming section) S12, and an oxidation processing chamber (oxidation processing section) S13 for performing oxidation processing.

The loading/unloading chamber S11 is provided with a conveying device (conveying mechanism) S11a and an exhaust device (exhausting mechanism) S11b. The conveying device S11a conveys the glass substrate S carried in from the outside to the film forming chamber S12. The exhaust device S11b is a rotary pump or the like for rough evacuating the inside of the loading/unloading chamber S11. The loading/unloading chamber S11 is connected to the film forming chamber S12 via a sealing device (sealing mechanism) S17.

The film forming chamber S12 is provided with a substrate holding device (substrate holding mechanism) S12a, a cathode electrode (back plate) S12c having a target S12b, a power source S12d, a gas introduction device (gas introduction mechanism) S12e, and a high vacuum exhaust device S12f.

The substrate holding device S12a receives the glass substrate S conveyed by the conveying device S11a, and holds the glass substrate S so as to face the target S12b during film formation. The substrate holding device S12a can carry in the glass substrate S from the loading/unloading chamber S11. The substrate holding device S12a can carry out the glass substrate S to the loading/unloading chamber S11 again.

The target S12b is formed of a material having a composition required to form a film of the following original half-tone layer 11A on the glass substrate S. The power supply S12d applies a negative potential sputtering voltage to the cathode electrode (back plate) S12c having the target S12b.

The gas introduction device S12e introduces gas into the film forming chamber S12. The high-vacuum exhaust device S12f is a turbo-molecular pump or the like for highly evacuating the inside of the film forming chamber S12. The cathode electrode (back plate) S12c, the power source S12d, the gas introduction device S12e, and the high vacuum exhaust device S12f have at least a structure for supplying the material for the film-forming semi-tone layer 11. The film formation chamber S12 is connected to the oxidation treatment chamber S13 via a sealing device S18.

The oxidation processing chamber S13 is provided with a substrate holding device S13a, a gas introduction device S13e, a gas excitation device (gas excitation mechanism) S13r, and a high vacuum exhaust device S13f.

The substrate holding device S13a receives the glass substrate S conveyed by the substrate holding device S12a, and holds the glass substrate S in such a way that it faces the gas excitation device S13r during the oxidation process. The substrate holding device S13a can carry in the glass substrate S from the film forming chamber S12. The substrate holding device S13a can again carry the glass substrate S out to the film forming chamber S12.

The gas introduction device S13e introduces gas into the oxidation processing chamber S13. The high-vacuum exhaust device S13f is a turbo-molecular pump or the like for highly evacuating the inside of the oxidation processing chamber S13. The gas excitation device S13r excites the gas supplied from the gas introduction device S13e to the inside of the oxidation processing chamber S13 to turn it into an excited oxidation gas.

Here, the term “excited oxidizing gas” means plasma, radicals, ions, and other states. The gas excitation device S13r can eject the excited oxidation gas toward the glass substrate S held by the substrate holding device S13a. The gas excitation device S13r, the gas introduction device S13e, and the high-vacuum exhaust device S13f have a structure for oxidizing the original half-tone layer 11A. In addition, the gas excitation device S13r and the gas introduction device S13e are excitation gas supply parts.

In the manufacturing apparatus S10 shown in FIG. 3, for the glass substrate S carried in from the loading/unloading chamber S11, first, the original half-tone layer is formed by sputtering in the film forming chamber (vacuum processing chamber) S12 11A. After that, the original half-tone layer 11A is oxidized in the oxidation treatment chamber S13 to form the half-tone layer 11. Then, the glass substrate S after the processing is carried out from the loading/unloading chamber S11 to the outside.

During film formation, sputtering gas and reaction gas are supplied to the film formation chamber S12 from the gas introduction device S12e, and a sputtering voltage is applied to the back plate (cathode electrode) S12c from an external power source. In addition, a specific magnetic field can also be formed on the target S12b by a magnetron circuit. The ions of the sputtering gas excited by the plasma in the film forming chamber S12 collide with the target S12b of the cathode electrode S12c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they adhere to the glass substrate S, thereby forming a specific film on the surface of the glass substrate S.

Fig. 4 is a schematic diagram showing a manufacturing apparatus for manufacturing a mask substrate in this embodiment. The manufacturing device S20 shown in FIG. 4 is a continuous sputtering device and a device capable of performing oxidation treatment. The manufacturing apparatus S20 has a loading chamber S21, a film forming chamber (vacuum processing chamber, film forming section) S22, an oxidation processing chamber (oxidation processing section) S23, and an unloading chamber S25.

The loading chamber S21 is provided with a conveying device S21a and an exhaust device S21b. The conveying device S21a conveys the glass substrate S carried in from the outside to the film forming chamber S22. The exhaust device S21b is a rotary pump which roughly evacuates the inside of the loading chamber S21. The loading chamber S21 is connected to the film formation chamber (vacuum processing chamber) S22 via the sealing device S27.

The film forming chamber S22 is provided with a substrate holding device S22a, a cathode electrode (back plate) S22c having a target S22b, a power source S22d, a gas introduction device S22e, and a high vacuum exhaust device S22f.

The substrate holding device S22a receives the glass substrate S conveyed by the conveying device S21a, and holds the glass substrate S so as to face the target S22b during film formation. The substrate holding device S22a can carry in the glass substrate S from the loading chamber S21. The substrate holding device S22a can again carry the glass substrate S out to the oxidation treatment chamber (oxidation treatment part) S23.

The target S22b is formed of a material having a composition required to form a film of the original half-tone layer 11A described below on the glass substrate S. The cathode electrode (back plate) S22c, the power supply S22d, the gas introduction device S22e, and the high-vacuum exhaust device S22f have a structure for supplying materials for the film-forming semitone layer 11 and the like.

The power supply S22d applies a negative potential sputtering voltage to the cathode electrode (back plate) S22c having the target S22b. The gas introduction device S22e introduces gas into the film forming chamber S22. The high-vacuum exhaust device S22f is a turbo-molecular pump or the like for high-evacuating the inside of the film forming chamber S22. The film formation chamber S22 is connected to the oxidation treatment chamber (oxidation treatment part) S23 via a sealing device S28.

The oxidation processing chamber S23 is provided with a substrate holding device S23a, a gas introduction device S23e, a gas excitation device S23r, and a high vacuum exhaust device S23f.

The substrate holding device S23a receives the glass substrate S transported by the substrate holding device S22a, and holds the glass substrate S so as to face the gas excitation device S23r during the oxidation process. The substrate holding device S23a can carry in the glass substrate S from the film forming chamber S22. The substrate holding device S23a can carry out the glass substrate S to the unloading chamber S25 again.

The gas introduction device S23e introduces gas into the oxidation processing chamber S23. The high-vacuum exhaust device S23f is a turbo-molecular pump or the like for highly evacuating the inside of the oxidation treatment chamber S23. The gas excitation device S23r excites the gas supplied from the gas introduction device S23e to the inside of the oxidation processing chamber S23 to turn it into an excited oxidation gas.

Here, the term “excited oxidizing gas” means the state of plasma, radicals, ions, and the like. The gas excitation device S23r can eject the excited oxidation gas toward the glass substrate S held by the substrate holding device S23a. The gas excitation device S23r and the gas introduction device S23e are excitation gas supply parts.

In addition, the gas excitation device S23r, the gas introduction device S23e, and the high vacuum exhaust device S23f have at least a structure for performing oxidation treatment on the original half-tone layer 11A. The oxidation treatment chamber (oxidation treatment part) S23 is connected to the unloading chamber S25 via a sealing device S28.

The unloading chamber S25 is provided with a conveying device S25a for conveying the glass substrate S carried in from the oxidation treatment chamber (oxidation treatment part) S23 to the outside, and an exhaust device S25b such as a rotary pump for rough vacuuming the chamber.

In the manufacturing apparatus S20 shown in FIG. 4, for the glass substrate S carried in from the loading chamber S21, first, the original semi-tone layer 11A is formed by sputtering in the film forming chamber (vacuum processing chamber) S22. Thereafter, the original half-tone layer 11A is subjected to oxidation treatment in the oxidation treatment chamber S23. Then, the glass substrate S on which the film formation has been completed is carried out from the unloading chamber S25 to the outside.

FIG. 5 is a flowchart showing the manufacturing steps of the mask substrate and the half-dimmer mask in this embodiment. 6 to 10 are cross-sectional views showing the manufacturing steps of the mask substrate in this embodiment. The manufacturing method of the mask base MB in this embodiment is shown in FIG. 5, which has a substrate preparation step S00, a original half-tone layer filming step S01a, an oxidation treatment step S01b, an etching stop layer filming step S02, and a light-shielding layer filming step. Step S03.

Here, in the description of the manufacturing method of the mask substrate MB of the present embodiment, the processing performed by the manufacturing apparatus S20 shown in FIG. 4 will be described. When the mask substrate MB is manufactured by the manufacturing apparatus S10 shown in FIG. 3, the symbol of the code S20 is replaced with the code S10, and the unloading chamber S25 is replaced with the loading/unloading chamber S11, etc.

In the substrate preparation step S00 shown in FIG. 5, the glass substrate S (FIG. 6) that has undergone the above-mentioned surface treatment and the like is prepared. After that, the transparent substrate S is carried into the loading chamber S21 shown in FIG. 4. In the loading chamber S21, the transparent substrate S is supported by the conveying device S21a, and after the loading chamber S21 is sealed, the inside of the loading chamber S21 is roughly evacuated by the exhaust device S21b.

In this state, the sealing device S27 is released, the transparent substrate S is conveyed by the conveying device S21a, and the conveyed glass substrate S is received by the substrate holding device S22a, and the transparent substrate S is moved into the film forming chamber (vacuum processing chamber) S22. In the film forming chamber S22, the sealing device S27 is sealed. In the film forming chamber (vacuum processing chamber) S22, the transparent substrate S is held by the substrate holding device S22a.

In the original semi-tone layer film forming step S01a shown in FIG. 5, in the film forming chamber (vacuum processing chamber) S22 shown in FIG. 4, the inside of the film forming chamber S22 is elevated by a high-vacuum exhaust device S22f. Vacuum. Then, the sputtering gas and the reaction gas are supplied from the gas introduction device S22e to the film forming chamber S22, and the sputtering voltage is applied to the back plate (cathode electrode) S22c from an external power source. In addition, a specific magnetic field can also be formed on the target S22b by a magnetron circuit.

The ions of the sputtering gas excited by the plasma in the film forming chamber S22 collide with the target S22b of the cathode electrode S22c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they adhere to the glass substrate S, thereby forming a film of the original half-tone layer 11A on the surface of the glass substrate S (FIG. 7 ).

Here, the target S22b having the composition required for film formation of the original half-tone layer 11A is replaced in advance. In addition, as the film forming gas required for the film formation of the original half-tone layer 11A, different amounts of nitrogen and the like are supplied from the gas introduction device S22e, and the partial pressure is controlled to switch so that the composition is within the set range . At this time, the original half-tone layer 11A to be formed is as shown in FIG. 19 below, and may have specific oxygen composition ratio, carbon composition ratio, nitrogen composition ratio, and chromium composition ratio in the thickness direction.

In the oxidation treatment step S01b shown in FIG. 5, the sealing device S28 is released from the film forming chamber S22 shown in FIG. 4, the transparent substrate S is conveyed by the substrate holding device S22a, and the conveyed glass is received by the substrate holding device S23a The substrate S, and the transparent substrate S is carried into the oxidation treatment chamber S23. The original half-tone layer 11A is formed on the transparent substrate S. In the oxidation treatment chamber S23, the sealing device S28 is sealed. In the oxidation treatment chamber S23, the transparent substrate S is held by the substrate holding device S23a.

In the oxidation treatment chamber S23, the inside of the oxidation treatment chamber S23 is highly evacuated by the high-vacuum exhaust device S23f. Then, the oxidation treatment gas is supplied from the gas introduction device S23e to the oxidation treatment chamber S23. At the same time, the gas supplied from the gas introduction device S23e to the inside of the oxidation treatment chamber S23 is excited by the gas excitation device S23r to turn it into an excited oxidation gas such as plasma, radicals, and ions.

The gas excitation device S23r sprays an excited oxidation gas toward the surface of the original half-tone layer 11A of the glass substrate S. The original half-tone layer 11A, which is blown with the excited oxidizing gas, is oxidized, as shown in the following Fig. 20, to have specific oxygen composition ratio, carbon composition ratio, nitrogen composition ratio, and chromium composition ratio in the thickness direction. Adjust layer 11 (Figure 8).

In the half-tone layer 11, a drug-resistant layer 11a is formed at a position which is the outermost surface in the thickness direction. In addition, in the half-tone layer 11, an optical characteristic layer 11b is formed at a position close to the transparent substrate S in the thickness direction. The drug-resistant layer 11a is formed such that the composition ratio of oxygen is higher than the composition ratio of chromium to the composition ratio of nitrogen as described above. In addition, the optical characteristic layer 11b is formed so that the composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen as described above.

At this time, as the oxidation treatment gas, any gas that can oxidize the original half-tone layer 11A containing chromium or the like is sufficient, and oxygen, carbon dioxide, and N ₂ O, NO as nitrogen oxidizing gas are suitable.

Here, in order to form the half-tone layer 11 having the drug-resistant layer 11a and the optical characteristic layer 11b, it is necessary to accurately control the oxidation state. Therefore, the oxidation ability of the oxidation treatment gas should not be too strong.

For example, the oxidation capacity of the oxidation treatment gas in the oxidation treatment step S01b is sequentially reduced as follows: O ₂ > H ₂ O> CO ₂ >CO> N ₂ O> NO. Therefore, in order to precisely control the oxidation state of chromium, Preferably, NO gas is used. _{Here, the composition ratio when using CO 2} gas, which has a stronger oxidizing power than NO gas, is shown in Fig. 21 below.

In addition, the conditions of the oxidation treatment gas can be controlled by the flow rate of the gas introduced into the apparatus for performing the oxidation treatment, for example, it can be controlled by the flow rate of the oxidation treatment gas. Furthermore, it can also be processed by diluting with a gas such as nitrogen or argon.

In addition, as the excitation condition of the oxidation treatment gas, when plasma discharge is used, the excitation state can be controlled by the discharge pressure or the discharge power. In addition, in the sputtering device, it is also possible to perform oxidation treatment by reducing the discharge power to reduce the film formation speed.

In the etching stop layer forming step S02 shown in FIG. 5, the sealing device S28 shown in FIG. 4 is released, and the transparent substrate S is transported from the oxidation processing chamber S23 by the substrate holding device S23a, and the substrate holding device S22a is received and transported. The glass substrate S is reached, and the transparent substrate S is carried into the film forming chamber S22.

In the film forming chamber (vacuum processing chamber) S22, the inside of the film forming chamber S22 is highly evacuated by the high vacuum exhaust device S22f. Then, the sputtering gas and the reaction gas are supplied from the gas introduction device S22e to the film forming chamber S22, and the sputtering voltage is applied to the back plate (cathode electrode) S22c from an external power source. In addition, a specific magnetic field can also be formed on the target S22b by a magnetron circuit.

The ions of the sputtering gas excited by the plasma in the film forming chamber S22 collide with the target S22b of the cathode electrode S22c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they adhere to the glass substrate S, thereby forming an etching stop layer 12 on the surface of the glass substrate S (FIG. 9 ).

Here, the target S22b having the composition required for film formation of the etching stop layer 12 is replaced in advance. In addition, as the film forming gas required for the film formation of the etching stop layer 12, different amounts of nitrogen and the like are supplied from the gas introduction device S22e, and the partial pressure is switched so that the composition is within the set range.

Specifically, a metal silicide film is formed as the etching stop layer 12. As the metal silicide film, various films can be used. In this embodiment, molybdenum silicide is used. At this time, in order to form molybdenum silicide, reactive sputtering can be used to form it.

Molybdenum silicide has the property that if the film does not contain nitrogen, it is easily etched by acid or alkaline solutions. Therefore, when molybdenum silicide is used as an etching stop film, molybdenum silicide containing nitrogen is used.

Here, when the molybdenum silicide is formed by the reactive sputtering method, nitrogen containing nitrogen, nitrogen monoxide, nitrogen dioxide, etc. are used as an additive gas. Thereby, a molybdenum silicide containing nitrogen in the film can be formed. Furthermore, by controlling the gas flow rate of the added gas, the content of nitrogen contained in the molybdenum silicide can also be controlled.

In the light-shielding layer film forming step S03 shown in FIG. 5, in the film forming chamber (vacuum processing chamber) S22 shown in FIG. 4, the inside of the film forming chamber S22 is highly evacuated by the high vacuum exhaust device S22f . Then, the sputtering gas and the reaction gas are supplied from the gas introduction device S22e to the film forming chamber S22, and the sputtering voltage is applied to the back plate (cathode electrode) S22c from an external power source. In addition, a specific magnetic field can also be formed on the target S22b by a magnetron circuit.

The ions of the sputtering gas excited by the plasma in the film forming chamber S22 collide with the target S22b of the cathode electrode S22c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they adhere to the glass substrate S, thereby forming a light-shielding layer 13 on the surface of the glass substrate S (FIG. 10 ).

Here, the target S22b having the composition required for film formation of the light-shielding layer 13 is replaced in advance. In addition, as the film forming gas required for the film formation of the light-shielding layer 13, different amounts of nitrogen and the like are supplied from the gas introduction device S22e, and the partial pressure is switched so that the composition is within the set range.

The light shielding layer 13 is mainly composed of chromium. At this time, in order to reduce the reflectivity of the light-shielding layer 13, an anti-reflection layer with an increased oxygen concentration and a lower refractive index may be formed on the surface of the light-shielding film.

Furthermore, when other films are laminated in addition to the half-tone layer 11, the etching stop layer 12, and the light shielding layer 13, the corresponding target, gas and other sputtering conditions are used to form the film by sputtering, or The corresponding films are laminated by other film forming methods to manufacture the mask substrate MB of the present embodiment shown in FIG. 1.

It is possible to form a semi-dimmer mask substrate with a metal silicide film as the underlying structure of the etching stop film.

Hereinafter, a method of manufacturing the half-dimmer mask M from the mask substrate MB of the present embodiment manufactured in this manner will be described. 11 to 18 are cross-sectional views showing the steps of manufacturing a half-dimmer mask from the mask substrate in this embodiment.

The manufacturing method of the half-dimmer mask M in this embodiment is shown in FIG. 5, which has a photoresist layer forming step S04a, a photoresist pattern forming step S04b, a transmission pattern forming step S04c, a cleaning step S04d, and a photoresist layer forming step. S05a, photoresist pattern forming step S05b, light shielding pattern forming step S05c, etching stop pattern forming step S05d, and cleaning step S05e.

As the photoresist layer forming step S04a shown in FIG. 5, a photoresist layer PR1 is formed on the uppermost layer of the mask base MB, that is, on the light-shielding layer 13 (FIG. 11). The photoresist layer PR1 may be a positive type or a negative type, and it can be set to a positive type here. As the photoresist layer PR1, a liquid photoresist, an adhesive film, etc. can be used.

In the photoresist pattern forming step S04b shown in FIG. 5, by exposing and developing the photoresist layer PR1, a photoresist pattern PR1p having a specific pattern shape (opening pattern) is formed on the light shielding layer 13 (FIG. 12) . The photoresist pattern PR1p functions as an etching mask for the light-shielding layer 13, the etching stop layer 12, and the half-tone layer 11, and the shape is appropriately defined according to the etching patterns of the respective layers 11, 12, and 13. As an example, the photoresist pattern PR1p is set to a shape corresponding to the halftone area M2 and the light-shielding area M3 except for the transparent area M1 where the glass substrate S is exposed.

Then, as the transmission pattern forming step S04c shown in FIG. 5, the light shielding layer 13, the etching stop layer 12, and the half tone layer 11 are sequentially wet-etched using a specific etching solution over the photoresist pattern PR1p. At this time, in the etching of the light-shielding layer 13 and the half-tone layer 11 containing chromium, a chromium etchant, such as an etchant containing cerium ammonium nitrate, can be used.

In addition, in the etching of the etching stop layer 12, different etchants can be used, for example, including at least one fluorine compound selected from hydrofluoric acid, fluorosilicic acid, and ammonium hydrogen fluoride, and selected from hydrogen peroxide, nitric acid, and sulfuric acid The material of at least one oxidant. Thereby, the light-shielding layer transmission pattern 13p0, the etching stop layer transmission pattern 12p0, and the halftone pattern 11p are formed (FIG. 13).

Then, in the cleaning step S04d shown in FIG. 5, a specific cleaning solution is used to remove the photoresist pattern PR1p. As the cleaning liquid, a sulfuric acid hydrogen peroxide mixture or ozone water can be used. The mask base MB in this state has a region where the light-shielding layer transmission pattern 13p0, the etching stop layer transmission pattern 12p0 and the halftone pattern 11p are formed, and the transmission region M1 exposed by the glass substrate S (FIG. 14 ).

Next, as the photoresist layer forming step S05a shown in FIG. 5, a photoresist layer PR2 is formed on the uppermost layer of the mask base MB, that is, the light-shielding layer transmission pattern 13p0. At this time, a photoresist layer PR2 is also formed in the transmission region M1 (FIG. 15). The photoresist layer PR2 may be a positive type or a negative type, and it may be a positive type here. As the photoresist layer PR2, a liquid photoresist can be used.

Then, as the photoresist pattern forming step S05b shown in FIG. 5, by exposing and developing the photoresist layer PR2, a photoresist pattern PR2p is formed on the light-shielding layer transmission pattern 13p0 (FIG. 16). The photoresist pattern PR2p functions as an etching mask for the light-shielding layer transmission pattern 13p0 and the etching stop layer transmission pattern 12p0.

The photoresist pattern PR2p is appropriately defined in shape according to the etching pattern of the halftone region M2 in which the light-shielding layer transmission pattern 13p0 and the etching stop layer transmission pattern 12p0 are removed. As an example, the photoresist pattern PR2p is set in the half-tone area M2 to have a shape having an opening width corresponding to the opening width of the light shielding pattern 13p and the etching stop pattern 12p to be formed.

Then, as the light-shielding pattern formation step S05c shown in FIG. 5, the following step is started: the light-shielding layer transmission pattern 13p0 is wet-etched using a specific etching solution (etchant) over the photoresist pattern PR2p.

When the light-shielding layer transmission pattern 13p0 is etched, it is important that the etching stop layer transmission pattern 12p0 is not etched by the etchant of the light-shielding layer transmission pattern 13p0. When the light shielding layer transmission pattern 13p0 with chromium as the main component is used, as the etching solution, an etching solution containing cerium ammonium nitrate can be used.

Furthermore, it is preferable to use cerium ammonium nitrate containing an acid such as nitric acid or perchloric acid. As the etching solution, a mixed solution of cerium ammonium nitrate and perchloric acid is generally used.

Here, the etch stop layer transmission pattern 12p0 has higher resistance to the etching solution than the light shielding layer transmission pattern 13p0. Therefore, first, only the light-shielding layer transmission pattern 13p0 is patterned to form the light-shielding pattern 13p. The light-shielding pattern 13p has an opening width corresponding to the photoresist pattern PR2p, and is removed into a shape corresponding to the halftone area M2. The light-shielding pattern 13p is formed in a shape corresponding to the light-shielding area M3 (FIG. 17).

At this time, the etching stop layer has a necessary selection ratio to the etching solution through the pattern 12p0, and the etching rate is set to be extremely small. Therefore, the etching stop layer has sufficient etching resistance through the pattern 12p0. Therefore, the halftone layer 11 having Cr in the same system as the light shielding layer 13 will not be damaged.

Then, as the etching stop pattern forming step S05d shown in FIG. 5, the following step is started: the etching stop layer transmission pattern 12p0 is wet-etched using a specific etching solution over the photoresist pattern PR2p and the light shielding pattern 13p.

As for the etching solution, when the etching stop layer 12 is MoSi, as the etching solution, it is preferable to use at least one fluorine compound selected from the group consisting of hydrofluoric acid, fluorosilicic acid, and ammonium bifluoride. , And a material selected from at least one oxidant selected from hydrogen peroxide, nitric acid, and sulfuric acid.

Regarding the wet etching of the etching stopper through the pattern 12p0, in the halftone area M2 not covered by the light shielding pattern 13p, the etching stopper through the pattern 12p0 is etched to form the etching stopper pattern 12p (FIG. 18).

When the etching stop layer is etched through the pattern 12p0 and the half-tone layer 11 is exposed, the etching of the etching stop layer 12 ends. Thereby, in the halftone area M2, the halftone pattern 11p is exposed.

Then, as the cleaning step S05e shown in FIG. 5, the photoresist pattern PR2p is removed. As the cleaning liquid, a sulfuric acid hydrogen peroxide mixture or ozone water can be used. At this time, in the light-shielding area M3 where the light-shielding pattern 13p is laminated, the washing water does not contact the halftone pattern 11p. In contrast, in the halftone area M2, the washing water is in contact with the halftone pattern 11p.

In the washing of the halftone pattern 11p, the drug-resistant layer 11a is arranged on the exposed surface. The drug-resistant layer 11a has the above-mentioned composition ratio of oxygen and the like, so that it is resistant to a cleaning solution made of a sulfuric acid hydrogen peroxide mixture or ozone water. Therefore, the drug-resistant layer 11a prevents the optical characteristic layer 11b from changing the film thickness or optical characteristics caused by the cleaning solution in the cleaning step S05e.

Therefore, the drug-resistant layer 11a can suppress the change in the film thickness or optical properties of the halftone pattern 11p caused by the cleaning solution in the cleaning step S05e. Thereby, in the halftone pattern 11p, the optical characteristic layer 11b can ensure the optical characteristic.

Thereby, as shown in FIG. 2, a half-tone mask M can be obtained, which includes a specific light-shielding pattern 13p and an etching stop pattern 12p that have been optically set, and a half-tone pattern 11p having desired optical characteristics, and is formed with The transmission area M1, the halftone area M2, and the light-shielding area M3.

Or, in the above process steps, after processing the molybdenum silicide film that will become the etching stop layer 12, the molybdenum silicide film is used as a mask to etch the half-tone layer 11 mainly composed of chromium. After that, the photoresist layer is peeled off, thereby processing the light-shielding layer 13, the etching stop layer 12, and the half-tone layer 11 to complete. Here, only the light-shielding layer transmission pattern 13p0 and the etching stop layer transmission pattern 12p0 are etched, whereby only the pattern of the half-tone layer 11 can be formed.

According to the mask substrate MB of this embodiment, as shown in FIG. 1, by making the half-tone layer 11 have a drug-resistant layer 11a and an optical characteristic layer 11b, a half-tone mask M having desired optical characteristics can be manufactured. In addition, by using the original half-tone layer forming step S01a to form the original half-tone layer 11A, and using the oxidation treatment step S01b to perform oxidation treatment on the original half-tone layer 11A, it is possible to form a half that has drug resistance and optical characteristic change inhibitory effects.调层11。 Adjust layer 11. Therefore, as long as the oxidation treatment step S01b is added to the previous manufacturing steps, the half-dimmer mask M having the desired optical characteristics can be manufactured.

In addition, according to the mask substrate MB of the present embodiment, as shown in FIG. 2, it is possible to manufacture a semi-dimming light that can simultaneously maintain the chemical resistance and the optical characteristic change suppression effect in the cleaning step S05e, and has the desired optical characteristics Cover M.

Hereinafter, the photomask base, the semi-dimmer mask, the manufacturing method, and the manufacturing apparatus of the second embodiment of the present invention will be described based on the drawings. 26 to 37 are diagrams showing the steps of the manufacturing method of the semi-dimmer mask in this embodiment, and FIG. 38 is a flowchart showing the manufacturing method of the mask substrate and the semi-dimmer mask in this embodiment. In this embodiment, the difference from the above-mentioned first embodiment lies in the stacking position of the halftone layer, and other components corresponding to the above-mentioned first embodiment are denoted by the same reference numerals, and their description is omitted.

As shown in FIG. 33, the mask base MB of this embodiment includes a transparent substrate S, a light-shielding layer 13 formed on the transparent substrate S, and a half-tone layer 11 formed on the light-shielding layer 13. The light-shielding layer 13 may also be a light-shielding pattern 13p.

The half-tone layer 11 has a drug-resistant layer 11a in which the composition ratio of oxygen is higher than the composition ratio of chromium and the composition ratio of nitrogen at the position which becomes the most surface in the thickness direction. In addition, the half-tone layer 11 has an optical characteristic layer 11b whose composition ratio of oxygen is lower than that of chromium and that of nitrogen at a position adjacent to the transparent substrate S and the light-shielding pattern 13p in the thickness direction. The composition ratio of the halftone layer 11 is the same as that of the above-mentioned first embodiment.

As shown in FIG. 37, the half-tone mask M of this embodiment has a transmission area M1, a half-tone area M2, and a light-shielding area M3 in the mask base MB.

The transmission area M1 is an area where the glass substrate (transparent substrate) S is exposed. The halftone area M2 is an area where the halftone pattern 11p obtained by patterning only the halftone layer 11 in the mask base MB is formed on the glass substrate (transparent substrate) S.

The light-shielding area M3 is a region where the light-shielding layer 13 and the half-tone layer 11 in the mask base MB are patterned, and the light-shielding pattern 13p and the half-tone pattern 11p are laminated.

The manufacturing method of the photomask base and the semi-dimmer mask in this embodiment is shown in FIG. 38, which has a substrate preparation step S00, a light shielding layer forming step S011, a photoresist layer forming step S012a, a photoresist pattern forming step S012b, and a light shielding step. Pattern formation step S012c, cleaning step S012d, original halftone layer forming step S013a, oxidation treatment step S013b, photoresist layer formation step S014a, photoresist pattern formation step S014b, transmission pattern formation step S014c, and cleaning step S014d.

Here, in the description of the manufacturing method of the photomask substrate of the present embodiment, similarly to the first embodiment, the processing performed by the manufacturing apparatus S20 shown in FIG. 4 will be described. When the mask substrate MB is manufactured by the manufacturing apparatus S10 shown in FIG. 3, the symbol of the code S20 is replaced with the code S10, and the unloading chamber S25 is replaced with the loading/unloading chamber S11, etc. In addition, in this embodiment, the operations in the manufacturing apparatus S20 will be omitted as appropriate.

In the substrate preparation step S00 shown in FIG. 38, the glass substrate S is prepared (FIG. 26). Thereafter, the transparent substrate S is carried into the film forming chamber (vacuum processing chamber) S22 through the loading chamber S21 shown in FIG. 4. In the film forming chamber (vacuum processing chamber) S22, the transparent substrate S is supported by the substrate holding device S22a.

In the light-shielding layer film forming step S011 shown in FIG. 38, in the film forming chamber (vacuum processing chamber) S22 shown in FIG. 4, the sputtering gas and the reaction gas are supplied from the gas introduction device S22e to the film forming chamber S22, from The external power supply applies a sputtering voltage to the back plate (cathode electrode) S22c. In addition, a specific magnetic field can also be formed on the target S22b by a magnetron circuit.

The ions of the sputtering gas excited by the plasma in the film forming chamber S22 collide with the target S22b of the cathode electrode S22c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they adhere to the glass substrate S, thereby forming a light-shielding layer 13 on the surface of the glass substrate S (FIG. 27 ).

The light shielding layer 13 is mainly composed of chromium. Here, the target S22b having the composition required for film formation of the light-shielding layer 13 is replaced in advance. In addition, as the film forming gas required for the film formation of the light-shielding layer 13, different amounts of nitrogen and the like are supplied from the gas introduction device S22e, and the partial pressure is switched so that the composition is within the set range. After that, the glass substrate S is carried out to the outside through the unloading chamber S25 shown in FIG. 4.

As the photoresist layer forming step S012a shown in FIG. 38, a photoresist layer PR1 is formed on the uppermost layer of the photomask substrate, that is, on the light-shielding layer 13 (FIG. 28). The photoresist layer PR1 may be a positive type or a negative type, and it can be set to a positive type here. As the photoresist layer PR1, a liquid photoresist, an adhesive film, etc. can be used.

In the photoresist pattern forming step S012b shown in FIG. 38, by exposing and developing the photoresist layer PR1, a photoresist pattern PR1p having a specific pattern shape (opening pattern) is formed on the light shielding layer 13 (FIG. 29) . The photoresist pattern PR1p functions as an etching mask of the light-shielding layer 13, and its shape is appropriately defined according to the etching pattern of the light-shielding layer 13. As an example, the photoresist pattern PR1p is set to a shape corresponding to the light-shielding area M3 except for the transparent area M1 and the half-tone area M2 where the glass substrate S is exposed.

Then, as the light-shielding pattern forming step S012c shown in FIG. 38, the light-shielding layer 13 is wet-etched using a specific etching solution over the photoresist pattern PR1p to form the light-shielding pattern 13p (FIG. 30). At this time, in the etching of the light-shielding layer 13 containing chromium, a chromium etchant, such as an etchant containing cerium ammonium nitrate, can be used.

Then, in the cleaning step S012d shown in FIG. 38, a specific cleaning solution is used to remove the photoresist pattern PR1p. As the cleaning liquid, a sulfuric acid hydrogen peroxide mixture or ozone water can be used. The mask base MB in this state has a light-shielding area M3 formed with a light-shielding pattern 13p, and areas M1 and M2 where the glass substrate S is exposed (FIG. 31).

Then, the transparent substrate S is carried into the film forming chamber (vacuum processing chamber) S22 shown in FIG. 4. In the original half-tone layer film formation step S013a shown in FIG. 38, in the film formation chamber (vacuum processing chamber) S22 shown in FIG. 4, sputtering gas and reaction gas are supplied from the gas introduction device S22e to the film formation chamber S22 , The sputtering voltage is applied to the back plate (cathode electrode) S22c from the external power supply. In addition, a specific magnetic field can also be formed on the target S22b by a magnetron circuit.

The ions of the sputtering gas excited by the plasma in the film forming chamber S22 collide with the target S22b of the cathode electrode S22c to cause the particles of the film forming material to fly out. Then, after the flying particles are bonded with the reaction gas, they are attached to the glass substrate S and the light-shielding pattern 13p, thereby forming the original half-tone layer 11A on the surface of the glass substrate S and the light-shielding pattern 13p (FIG. 32).

Here, the target S22b having the composition required for film formation of the original half-tone layer 11A is replaced in advance. In addition, as the film forming gas required for the film formation of the original half-tone layer 11A, different amounts of nitrogen and the like are supplied from the gas introduction device S22e, and the partial pressure is controlled to switch so that the composition is within the set range . At this time, the original half-tone layer 11A to be formed may have specific oxygen composition ratio, carbon composition ratio, nitrogen composition ratio, and chromium composition ratio in the thickness direction.

In the oxidation treatment step S013b shown in FIG. 38, the transparent substrate S is carried into the oxidation treatment chamber S23 from the film forming chamber S22 shown in FIG. The original half-tone layer 11A is formed on the transparent substrate S. In the oxidation treatment chamber S23, the transparent substrate S is held by the substrate holding device S23a.

In the oxidation treatment chamber S23, the inside of the oxidation treatment chamber S23 is highly evacuated by the high-vacuum exhaust device S23f. Then, the oxidation treatment gas is supplied from the gas introduction device S23e to the oxidation treatment chamber S23. At the same time, the gas supplied from the gas introduction device S23e to the inside of the oxidation treatment chamber S23 is excited by the gas excitation device S23r to turn it into an excited oxidation gas such as plasma, radicals, and ions.

The gas excitation device S23r sprays an excited oxidation gas toward the surface of the original half-tone layer 11A of the glass substrate S. The original half-tone layer 11A blown by the excited oxidizing gas is oxidized to become a half-tone layer 11 having specific oxygen composition ratio, carbon composition ratio, nitrogen composition ratio, and chromium composition ratio in the thickness direction (Figure 33) .

In the half-tone layer 11, a drug-resistant layer 11a is formed at a position which is the outermost surface in the thickness direction. In addition, in the half-tone layer 11, an optical characteristic layer 11b is formed at a position adjacent to the transparent substrate S and the light-shielding pattern 13p in the thickness direction. The drug-resistant layer 11a is formed such that the composition ratio of oxygen is higher than the composition ratio of chromium to the composition ratio of nitrogen as described above. In addition, the optical characteristic layer 11b is formed so that the composition ratio of oxygen is lower than the composition ratio of chromium to the composition ratio of nitrogen as described above.

At this time, as the oxidation treatment gas, any gas that can oxidize the original half-tone layer 11A containing chromium or the like is sufficient, and oxygen, carbon dioxide, and N ₂ O, NO as nitrogen oxidizing gas are suitable.

Here, in order to form the half-tone layer 11 having the drug-resistant layer 11a and the optical characteristic layer 11b, it is necessary to accurately control the oxidation state. Therefore, the oxidation ability of the oxidation treatment gas should not be too strong.

For example, the oxidation capacity of the oxidation treatment gas in the oxidation treatment step S01b is sequentially reduced as follows: O ₂ > H ₂ O> CO ₂ >CO> N ₂ O> NO. Therefore, in order to precisely control the oxidation state of chromium, Preferably, NO gas is used.

In addition, the conditions of the oxidation treatment gas can be controlled by the flow rate of the gas introduced into the apparatus for performing the oxidation treatment, for example, it can be controlled by the flow rate of the oxidation treatment gas. Furthermore, it can also be processed by diluting with a gas such as nitrogen or argon.

In addition, as the excitation condition of the oxidation treatment gas, when plasma discharge is used, the excitation state can be controlled by the discharge pressure or the discharge power. In addition, in the sputtering device, it is also possible to perform oxidation treatment by reducing the discharge power to reduce the film formation speed.

In the oxidation treatment step S01b, the oxidation state is precisely controlled, and the sheet resistance of the half-tone layer 11 is set to 1.3×10 ³ Ω/sq or less. Furthermore, the sheet resistance of the half-tone layer 11 may be set to 7.0×10 ² Ω/sq or more. After that, the glass substrate S is carried out to the outside through the unloading chamber S25 shown in FIG. 4.

Next, as the photoresist layer forming step S014a shown in FIG. 38, a photoresist layer PR2 is formed on the uppermost layer of the mask base MB, that is, the drug-resistant layer 11a of the half-tone layer 11. At this time, a photoresist layer PR2 is also formed in the transmission area M1, the half-tone area M2, and the light-shielding area M3 (FIG. 34). The photoresist layer PR2 may be a positive type or a negative type, and it may be a positive type here. As the photoresist layer PR2, a liquid photoresist can be used.

Then, as the photoresist pattern forming step S014b shown in FIG. 38, the photoresist pattern PR2p is formed on the drug-resistant layer 11a of the half-tone layer 11 by exposing and developing the photoresist layer PR2 (FIG. 35). The photoresist pattern PR2p functions as an etching mask of the half tone layer 11.

The shape of the photoresist pattern PR2p is appropriately defined according to the etching pattern of the transmission region M1 from which the halftone layer 11 is removed. The photoresist pattern PR2p is set to a shape corresponding to the halftone area M2 and the light-shielding area M3 except for the transparent area M1 where the glass substrate S is exposed.

Then, as the transmission pattern forming step S014c shown in FIG. 38, the following step is started: the half-tone layer 11 is wet-etched using a specific etching solution (etchant) over the photoresist pattern PR2p. In the case of using the half-tone layer 11 mainly composed of chromium, as the etching solution, an etching solution containing cerium ammonium nitrate can be used.

Furthermore, it is preferable to use cerium ammonium nitrate containing an acid such as nitric acid or perchloric acid. As the etching solution, a mixed solution of cerium ammonium nitrate and perchloric acid is generally used. The halftone pattern 11p has an opening shape corresponding to the photoresist pattern PR2p, and is removed into a shape corresponding to the halftone area M2 and the light shielding area M3. The halftone pattern 11p is formed in a shape corresponding to the transmission area M1 (FIG. 36).

Then, as the cleaning step S014d shown in FIG. 38, the photoresist pattern PR2p is removed. As the cleaning liquid, a sulfuric acid hydrogen peroxide mixture or ozone water can be used. At this time, in the light-shielding area M3 and the half-tone area M2, the washing water is in contact with the half-tone pattern 11p.

In the washing of the halftone pattern 11p, the drug-resistant layer 11a is arranged on the exposed surface. The drug-resistant layer 11a has the above-mentioned composition ratio of oxygen and the like, so that it is resistant to a cleaning solution made of a sulfuric acid hydrogen peroxide mixture or ozone water. Therefore, the drug-resistant layer 11a prevents the optical characteristic layer 11b from changing the film thickness or optical characteristics caused by the cleaning solution in the cleaning step S014d.

Therefore, the drug-resistant layer 11a can suppress the change in the film thickness or optical properties of the halftone pattern 11p caused by the cleaning solution in the cleaning step S014d. Thereby, in the halftone pattern 11p, the optical characteristic layer 11b can ensure the optical characteristic.

At the same time, by setting the sheet resistance of the half-tone layer 11 as described above, the difference in transmittance caused by the wavelength difference of the exposure light in the half-tone region M2 can be reduced. Furthermore, the relationship between the sheet resistance of the half-tone layer 11 and the difference in transmittance caused by the wavelength difference of the exposure light in the half-tone region M2 is shown in Fig. 39 as follows.

As a result, as shown in FIG. 37, a half-tone mask M can be obtained, which includes a specific light-shielding pattern 13p that has been optically set, and a half-tone pattern 11p having desired optical characteristics, and a transparent region M1 and a half-tone mask are formed. Adjusting area M2 and shading area M3.

According to the mask substrate MB of this embodiment, as shown in FIG. 33, by making the half-tone layer 11 have a drug-resistant layer 11a and an optical characteristic layer 11b, a half-tone mask M having desired optical characteristics can be manufactured.

In addition, by forming the original half-tone layer 11A in the original half-tone layer forming step S013a, and oxidizing the original half-tone layer 11A in the oxidation treatment step S013b, it is possible to form a chemical resistance, an effect of suppressing changes in optical properties, and The half-tone layer 11 that suppresses the difference in transmittance caused by the wavelength.

Therefore, as long as the oxidation treatment step S013b is added to the previous manufacturing steps, the half-dimmer mask M having the desired optical characteristics can be manufactured. Moreover, it is possible to manufacture the half-dimmer mask M without providing an etching stop layer and without forming an etching stop pattern.

Furthermore, by setting the sheet resistance of the half-tone layer 11, the difference in transmittance caused by the wavelength of the exposure light can be reduced in the half-tone layer 11. In this way, it is possible to manufacture the half-dimmer mask M that can suppress the occurrence of the difference in transmittance caused by the wavelength of the exposure light, and can easily cope with the exposure light of the composite wavelength.

According to this embodiment, a so-called top-mounted half-dimmer mask M in which the half-tone layer 11 is formed on the upper portion of the light-shielding pattern 13p can be manufactured. In the same manner as in the top-mounted half-dimmer mask M, when the half-tone pattern 11p is formed, the cleaning step S014d is performed using ozone, a sulfuric acid hydrogen peroxide mixture, or the like.

If the transmittance of the half-dimmer mask fluctuates in the cleaning step S014d, etc., when the mask is used to form a pattern, there will be a problem that the photoresist pattern as the object to be exposed cannot have the desired shape.

Therefore, by using the half-tone mask of this embodiment, not only can the transmittance difference (transmittance change) of the exposure wavelength be reduced, but also the transmittance change of the half-tone layer 11 after the cleaning step S014d using a chemical solution can be suppressed.

For the top-mounted half-dimmer mask, a chromium film that will become the light-shielding layer 13 is first formed on the glass substrate. Thereafter, in order to form the desired pattern, a photoresist process is used to pattern the chromium film. Thereafter, a half-tone layer 11 formed of a chromium film is formed. At this time, by applying the present invention, it is possible to form a half-tone layer with a small transmittance change even in the washing step.

Thereafter, the photoresist process is continued to form the half-tone layer into the desired pattern, thereby forming the top-mounted half-tone mask. [Example]

Hereinafter, embodiments of the present invention will be described.

Furthermore, as specific examples of the photomask substrate and the semi-dimmer mask in the present invention, the manufacturing of the photomask substrate will be described first.

＜Experimental example＞ First, a semi-transmissive half-tone film is formed on the glass substrate used to form the photomask. Here, the film is first formed as a film having the same composition ratio of chromium, oxygen, nitrogen, carbon, etc., and then subjected to oxidation treatment.

The halftone film formed at this time is preferably a film containing chromium, oxygen, nitrogen, carbon, etc. By controlling the composition and film thickness of chromium, oxygen, nitrogen, and carbon contained in the half-toning film during film formation and oxidation treatment, a half-toning film with desired transmittance can be obtained.

Thereafter, a metal silicide film is formed as an etching stop film. As the metal silicide film, various films can be used, and in this embodiment, molybdenum silicide is used. At this time, in order to form molybdenum silicide, reactive sputtering can be used to form it.

Molybdenum silicide has the property that if the film does not contain nitrogen, it is easily etched by acid or alkaline solutions. Therefore, when molybdenum silicide is used as an etching stop layer, a molybdenum silicide containing nitrogen is used.

Here, when the molybdenum silicide is formed by the reactive sputtering method, by using nitrogen containing nitrogen, nitrogen monoxide, nitrogen dioxide, etc. as an additive gas, the molybdenum silicide containing nitrogen in the film can be formed. Furthermore, in this case, by controlling the gas flow rate of the added gas, the content of nitrogen contained in the molybdenum silicide can also be controlled.

Thereafter, a light-shielding layer mainly composed of chromium is formed. At this time, in order to reduce the reflectivity of the light-shielding layer, an anti-reflection layer with an increased oxygen concentration and a lower refractive index is formed on the surface of the light-shielding layer. In this way, a semi-dimmer mask substrate with a structure below the etching stop layer is formed with the metal silicide film.

Furthermore, in the case of forming a half-dimmer mask, a photoresist process is first adopted, and the light-shielding film is processed into a desired pattern through process steps of photoresist coating, exposure, development, etching, and photoresist stripping. Here, when etching the light-shielding film, it is more important that the etching stop film is not etched by the etchant of the light-shielding film. When a light-shielding film mainly composed of chromium is used, a mixture of cerium ammonium nitrate and perchloric acid is generally used as an etching solution.

In the case of using molybdenum silicide as an etching stop film, since the molybdenum silicide faces the chromium etching solution, it is hardly etched, so it functions as a good etching stop film.

Secondly, regarding the molybdenum silicide film, the photoresist process is also used to process the etching stop film. Here, the etching solution used for etching the molybdenum silicide film is a solution containing hydrofluoric acid and an oxidizing agent.

After processing the molybdenum silicide film that will become the etching stop film, the molybdenum silicide film is used as a mask to etch the half-tone film mainly composed of chromium. After that, the photoresist film is peeled off, thereby completing the steps of processing the light-shielding film, the etching stop film, and the half-tone film.

As described above, in the bottom-mounted half-dimmer mask M, the patterning step using photoresist must be at least two times. Therefore, in the patterning step, the steps of processing each film with an etching solution or a cleaning solution are increased compared with the top-mounted semi-dimmer mask.

Therefore, the half-tone layer 11 is formed in the under-mounted half-tone mask M more front side than the light-shielding layer 13, and high liquid resistance is required. In addition, when the transmittance is set to be higher such that the transmittance of the half-tone layer 11 is 40% or higher, the film thickness of the half-tone layer 11 needs to be set thinner. Therefore, if the liquid resistance of the half-tone layer 11 is low, the transmittance changes greatly, and therefore, higher liquid resistance is required.

In addition, the importance of a flat half-tone film in which the wavelength dependence of the transmittance of the half-tone layer 11 is reduced has increased. In the exposure step of the panel in FPD manufacturing, the processing speed of exposure is very important. Therefore, in the exposure step, unlike the exposure step in semiconductors, multi-wavelength light is used.

Generally, the strong light of the high-pressure mercury lamp is the g-line (436 nm), h-line (405 nm), and i-line (365 nm) of the bright-line spectrum for exposure. Therefore, it is more ideal that the transmittances of these wavelengths are close to each other in the limit. Therefore, a metal chromium film that is relatively less likely to be oxidized as a half-tone film so far is generally used.

However, it is known that when a chromium film whose oxidation is relatively undeveloped is used as a half-tone film, the following problems occur. The problem is that in the cleaning step of the mixed solution of sulfuric acid and hydrogen peroxide water (sulfuric acid hydrogen peroxide mixture) used in the cleaning step of the photomask, or the ozone cleaning step, the halftone film is etched , So the transmittance of the half-tone film changes.

On the other hand, although the anti-drug properties can be improved by enhancing the oxidation of the half-toning film, when the oxygen concentration in the film is too high, the wavelength dependence of the transmittance becomes larger. In order to solve this problem, in this embodiment, the oxygen concentration on the surface of the half-toned film is increased, the oxygen concentration on the surface is appropriately controlled, and the oxygen concentration is reduced in the depth direction of the half-toned film, thereby reducing the transmittance The wavelength dependence is suppressed below a certain level, and at the same time, the drug resistance characteristics are improved.

<Experimental example 1> As Experimental Example 1, a half-toning film having the same composition ratio as the previously used half-toning film was formed. The formed half-toning film was not oxidized, and the composition of the half-toning film was evaluated by Ojie electron spectroscopy. The result is shown in Figure 19. Furthermore, the half-toned film whose composition evaluation is shown in FIG. 19 can be used as the original half-toned layer 11A.

<Experimental example 2> As Experimental Example 2, after forming the same half-tuning film as in Experimental Example 1, oxidation treatment was performed using NO gas. In this case, in the same manner as in Experimental Example 1, the composition evaluation of the half-toned film after the oxidation treatment was carried out by Ojie electron spectroscopy. The result is shown in Figure 20.

<Experimental Example 3> As Experimental Example 3, after forming the same half-tuning film as Experimental Example 1, oxidation treatment was performed _{using CO 2 gas.} In this case, in the same manner as in Experimental Example 1, the composition evaluation of the half-toned film after the oxidation treatment was carried out by Ojie electron spectroscopy. The result is shown in Figure 21.

From these results, it can be seen that the oxygen concentration in the film of the half-tuned film of Experimental Example 1 of the composition evaluation shown in FIG. 19 becomes lower. It can also be seen that by using NO gas and CO ₂ gas for oxidation treatment as in Experimental Example 2 and Experimental Example 3, the oxygen concentration on the surface of the half-tuning film can be increased. _{Furthermore, by performing oxidation treatment using NO gas and CO 2} gas as in Experimental Example 2 and Experimental Example 3, the film thickness of the semi-tuning film was increased. The positions in the thickness direction of the half-tuning film corresponding to this are indicated by arrows in FIGS. 19-22, respectively.

In addition, comparing the experimental example 2 of FIG. 20 with the experimental example 3 of FIG. 21, it can be seen that compared with _{the case of the experimental example 3 using CO 2} gas, the experimental example 2 using NO gas for oxidation treatment can be Only increase the oxygen concentration on the surface of the half-tuning film. It is believed that the reason is that _{the oxidizing power of CO 2} gas is higher than that of NO gas when excited by plasma.

Furthermore, for the above-mentioned semi-tuning film, the transmittance of h-line, the difference of transmittance between g-line and i-line, the film thickness, and the change in transmittance after washing by a mixture of sulfuric acid and hydrogen peroxide were measured. The results are shown in Table 1.

[Table 1] Experimental example 1 Experimental example 2 Experimental example 3 Transmittance (%) (h line) 55.4 56.04 57.5 Film thickness (nm) 4.1 6.0 7.7 Transmittance difference (%) (g line-i line) 0.03 0.89 1.47 Transmittance change (%) (before and after the sulphuric acid hydrogen peroxide mixture washing treatment) 3.41 1.01 1.17

From this result, it can be seen that in Experimental Examples 2 and 3 where the oxidation treatment was performed, the change in the transmittance of the semi-modulated film before and after the washing with the sulfuric acid hydrogen peroxide mixture was suppressed.

In addition, in experimental examples 2 and 3 where oxidation treatment was performed, the difference in transmittance between g-line and i-line was larger than that of experimental example 1 where oxidation treatment was not performed.

Furthermore, the half-tuning film of Experimental Example 2 in which NO gas was oxidized was able to reduce the difference in transmittance between g-line and i-line in comparison with the half-tuning film in Experimental Example 3 that was oxidized _{by CO 2 gas.} It is believed that the reason is that the oxidation treatment of the NO gas can suppress the internal oxidation of the half-tone film and enhance the oxidation of the surface of the half-tone film.

Secondly, in order to obtain a semi-tunable film with strong drug resistance and less wavelength dependence of transmittance, various NO gases are used to oxidize the semi-tunable film to change the surface oxygen concentration of the semi-tunable film, and the formed half-tone film is investigated. The transmittance changes before and after the membrane is cleaned with the sulfuric acid and hydrogen peroxide mixture.

＜Experiment example 4＞ As Experimental Example 4, the surface oxygen concentration of the semi-tuned film was changed, and the relationship between the surface oxygen concentration of the semi-tuned film and the change in transmittance before and after cleaning with the sulfuric acid hydrogen peroxide mixture was investigated. The result is shown in Figure 22.

<Experimental example 5> As Experimental Example 5, the relationship between the surface nitrogen concentration of the semi-modulated film and the change in transmittance before and after the cleaning with the sulfuric acid hydrogen peroxide mixture was investigated. The result is shown in Figure 23.

After studying the results of Experimental Examples 4 and 5, it can be seen that in order to improve the resistance to sulfuric acid and hydrogen peroxide mixtures, it is more desirable that the oxygen concentration on the surface of the semi-tuning film is 40% or more and the nitrogen concentration is 20% or less. Furthermore, the ranges of preferred composition ratios are shown in Figs. 22 and 23, respectively.

Secondly, in order to obtain a semi-tunable film with strong drug resistance and less wavelength dependence of transmittance, various NO gases are used to oxidize the semi-tunable film to change the surface oxygen concentration of the semi-tunable film, and the formed half-tone film is investigated. Adjust the spectral transmittance characteristics of the film.

<Experimental Example 6> In the same manner as in Experimental Example 4, the surface oxygen concentration of the half-toned film was changed. As Experimental Example 6, the relationship between the surface oxygen concentration of the half-toned film and the difference in transmittance between the g-line and the i-line was investigated. The result is shown in Figure 24.

<Experimental Example 7> In the same manner as in Experimental Example 5, the surface nitrogen concentration of the semi-tuned film was changed. As Experimental Example 7, the relationship between the surface nitrogen concentration of the semi-tuned film and the difference in transmittance between the g-line and the i-line was investigated. The result is shown in Figure 25.

Generally speaking, the difference between the g-line transmittance and the i-line transmittance required for the half-dimmer cover is about 0.6%. After studying the results of experimental examples 6 and 7, it can be seen that the oxygen concentration on the surface of the semi-tuning film that meets the above criteria is preferably 55% or less, and the nitrogen concentration is more preferably 15% or more. Furthermore, the ranges of preferred composition ratios are shown in Figs. 24 and 25, respectively.

It can be seen from the above research results that in order to obtain a half-toned film with higher resistance characteristics and less wavelength dependence of transmittance, it is better to oxidize the half-toned film by using NO gas to increase the surface of the half-toned film. Oxygen concentration reduces the oxygen concentration in the film.

Furthermore, it can be seen that the oxygen concentration on the surface of the semi-tuning film is more preferably 40% or more and 55% or less, and the nitrogen concentration is more preferably 15% or more and 20% or less. It can be seen that by applying the half-tuning film to the bottom-mounted half-tuning mask, it can be obtained that even if the liquid treatment required in the mask manufacturing step is performed, the transmittance change is small, and the wavelength dependence of the transmittance is small The half-dimmer cover.

In the above-mentioned embodiment, the description is given by taking the under-mounted semi-dimmer cover with many chemical liquid treatment steps as an example, but the present invention can also be applied to the semi-adjustable film formed on the light-shielding film and the over-mounted semi-dimmer cover . Thereby, it is possible to manufacture a top-mounted half-dimmer mask with strong liquid resistance and low wavelength dependence of transmittance.

Furthermore, in the above-mentioned embodiment, the original half-tone layer formed is oxidized to form the half-tone layer 11. However, it is also possible to supply an oxidation treatment gas during film formation so that the oxygen concentration becomes the above-mentioned composition ratio.调层11。 Adjust layer 11. In this case, an oxidation treatment gas supply part capable of supplying oxidation treatment gas may be provided in the film forming chambers S12 and S22, instead of installing the oxidation treatment chambers S13 and S23.

<Experimental Example 8> As Experimental Example 8, after forming the same half-tuning film as in Experimental Examples 1 to 7, oxidation treatment was performed using NO gas or the like. Furthermore, in the half-tuning film after oxidation treatment, the sheet resistance was measured. In this Experimental Example 8, the oxidation conditions were changed to change the sheet resistance in the range of 0.7×10 ³ Ω/sq to 1.3×10 ³ Ω/sq.

Furthermore, in a semi-tuning film with a change in sheet resistance, the light of g-line (436 nm) and i-line (365 nm) are used to measure their respective transmittances to calculate "g-line transmittance"-"i-line transmittance" The value of "is the difference between the g-line transmittance and the i-line transmittance (ΔT (g-i line) (%)). The result is shown in Figure 39.

From this result, it can be seen that the difference in transmittance between the g-line (436 nm) and the i-line (365 nm) of the half-tuning film of the present invention and the sheet resistance is as follows: as the sheet resistance becomes higher, the difference between the g-line and the i-line The difference in transmittance becomes larger.

The oxygen concentration of the semi-tuned film of the present invention greatly changes in the film thickness direction, and the oxygen concentration near the surface of the semi-tuned film is relatively high. Therefore, it can be seen that as the oxidation conditions in the oxidation step are strengthened, the oxygen concentration becomes higher, and consequently, the sheet resistance of the half-tone film becomes higher.

It can be seen that by changing the resistivity of the half-tone film in the depth direction, the resistivity near the surface of the half-tone film is increased, and the resistivity of the lower layer is reduced, and the effect of the present invention can be obtained. It has also been found that the half-tone film of the present invention can suppress the change in the difference in transmittance before and after wet etching. [Industrial availability]

As application examples of the present invention, photomasks and photomask substrates for semiconductors and flat panel displays can be cited.

MB: Mask base M: Half-dimmer hood M1: Through area M2: Halftone area M3: shading area PR1p, PR2p: photoresist pattern PR2, PR2: photoresist layer S: Glass substrate (transparent substrate) 11: Halftone layer 11a: Resistant layer 11b: Optical characteristic layer 11A: Original halftone layer 11p: Halftone pattern 12: Etch stop layer 12p0: etch stop layer transmission pattern 12p: etching stop pattern 13: shading layer 13p0: light shielding layer transmission pattern 13p: shading pattern

Fig. 1 is a cross-sectional view showing the first embodiment of the photomask substrate of the present invention. Fig. 2 is a cross-sectional view showing the half dimmer mask of the first embodiment of the present invention. Fig. 3 is a schematic diagram showing a film forming apparatus in a method of manufacturing a mask substrate according to the first embodiment of the present invention. Fig. 4 is a schematic diagram showing a film forming apparatus in a method of manufacturing a mask substrate according to the first embodiment of the present invention. FIG. 5 is a flowchart showing the manufacturing method of the mask substrate and the semi-dimmer mask according to the first embodiment of the present invention. Fig. 6 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 7 is a step diagram showing the manufacturing method of the half dimmer mask according to the first embodiment of the present invention. Fig. 8 is a step diagram showing the manufacturing method of the half dimmer mask according to the first embodiment of the present invention. Fig. 9 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 10 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 11 is a step diagram showing the manufacturing method of the half dimmer mask according to the first embodiment of the present invention. Fig. 12 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 13 is a step diagram showing the manufacturing method of the half dimmer mask according to the first embodiment of the present invention. Fig. 14 is a process chart showing a method of manufacturing a half-dimmer mask according to the first embodiment of the present invention. Fig. 15 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 16 is a step diagram showing the manufacturing method of the half dimmer mask according to the first embodiment of the present invention. Fig. 17 is a process chart showing a method of manufacturing a half-dimmer mask according to the first embodiment of the present invention. Fig. 18 is a step diagram showing the manufacturing method of the half-dimmer mask according to the first embodiment of the present invention. Fig. 19 is a graph showing an embodiment of the present invention. Fig. 20 is a graph showing an embodiment of the present invention. Fig. 21 is a graph showing an embodiment of the present invention. Fig. 22 is a graph showing an embodiment of the present invention. Fig. 23 is a graph showing an embodiment of the present invention. Fig. 24 is a graph showing an embodiment of the present invention. Fig. 25 is a graph showing an embodiment of the present invention. Fig. 26 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 27 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 28 is a process diagram showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 29 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 30 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 31 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 32 is a process chart showing a method of manufacturing a half dimmer mask according to the second embodiment of the present invention. Fig. 33 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 34 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 35 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 36 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 37 is a process chart showing a method of manufacturing a half-dimmer mask according to the second embodiment of the present invention. Fig. 38 is a flowchart showing a method of manufacturing a mask substrate and a half-dimmer mask according to the second embodiment of the present invention. Fig. 39 is a graph showing an embodiment of the present invention.

11: Halftone layer

11a: Resistant layer

11b: Optical characteristic layer

12: Etch stop layer

13: shading layer

MB: Mask base

S: Glass substrate (transparent substrate)

Claims (14)

A photomask substrate, which has: Transparent substrate The semi-tone layer, which is laminated on the surface of the transparent substrate, and contains Cr as the main component; An etching stop layer, which is laminated on the above-mentioned half-tone layer; and A light-shielding layer, which is laminated on the above-mentioned etching stop layer, and is mainly composed of Cr; and The most surface position of the half-tone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen, and a position close to the transparent substrate in the thickness direction has oxygen. An optical characteristic layer whose composition ratio is lower than that of chromium to that of nitrogen and that ensures optical characteristics. A photomask substrate, which has: Transparent substrate A light-shielding layer, which is laminated on the surface of the transparent substrate, and contains Cr as the main component; and The half-tone layer, which is laminated on the above-mentioned light-shielding layer, and contains Cr as the main component; and The most surface position of the half-tone layer in the thickness direction has a drug-resistant layer with a composition ratio of oxygen higher than that of chromium and nitrogen, and a position close to the transparent substrate in the thickness direction has oxygen. An optical characteristic layer whose composition ratio is lower than that of chromium to that of nitrogen and that ensures optical characteristics. The photomask substrate of claim 1 or 2, wherein in the halftone layer, the composition ratio of oxygen decreases from the most surface position in the thickness direction toward the position adjacent to the transparent substrate. The photomask substrate of claim 1 or 2, wherein in the halftone layer, the composition ratio of oxygen in the drug-resistant layer is set to be greater than 4 times the composition ratio of the smallest oxygen in the optical characteristic layer. Such as the photomask substrate of claim 1 or 2, wherein in the above-mentioned half-tone layer, the sheet resistance is set to 1.3×10 ³ Ω/sq or less. A method for manufacturing a photomask substrate, which is a method for manufacturing the photomask substrate according to any one of claims 1 to 5, and has: In the film forming step, the original half-tone layer with Cr as the main component is laminated; and The oxidation treatment step is to oxidize the original half-tone layer formed in the above-mentioned film-forming step to turn it into the above-mentioned half-tone layer. The method for manufacturing a photomask substrate according to claim 6, wherein in the oxidation treatment step, the oxidation treatment of the original half-tone layer is performed by the excited oxidation treatment gas. The method for manufacturing a photomask substrate according to claim 7, wherein the oxidation treatment gas in the oxidation treatment step is nitrogen oxide. A method for manufacturing a photomask substrate, which is a method for manufacturing the photomask substrate according to any one of claims 1 to 5, and It has the film forming step of stacking the above-mentioned semi-tone layer with Cr as the main component. A method for manufacturing a half-dimmer mask, which is a method for manufacturing a half-dimmer mask using the mask substrate of any one of claims 1 to 5, and has: The step of patterning the above-mentioned half-tone layer by a photomask with a specific pattern; and The cleaning step of removing the above-mentioned mask. According to claim 10, the method for manufacturing a semi-dimmer mask, wherein in the above-mentioned cleaning step, a sulfuric acid hydrogen peroxide mixture or ozone water is used as a cleaning liquid. A half-dimmer cover manufactured by the manufacturing method of claim 10 or 11. A manufacturing device for a photomask substrate, which is used in the manufacturing method of a photomask substrate as claimed in any one of Claims 6 to 8, and has: The film-forming part, which forms the above-mentioned original half-tone layer; and An oxidation treatment part, which performs oxidation treatment on the above-mentioned original half-tone layer; and The oxidation treatment part is provided with an excitation gas supply part capable of exciting and supplying the oxidation treatment gas. A manufacturing device for a photomask substrate, which is used in the manufacturing method of a photomask substrate as claimed in claim 9, and Having a film-forming part for forming the above-mentioned half-tone layer, and The film forming part is provided with an excitation gas supply part capable of exciting and supplying an oxidation treatment gas.

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