JP2015094901A - Method of producing mask blank and method of producing transfer mask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mask blank that has high adhesiveness with a resist film, wherein foreign objects derived from the resist film hardly remain in a space portion at the time of development, which results in few foreign objects and few defects.SOLUTION: A method of producing a mask blank includes the steps of: forming a thin film 11 on a substrate 10; applying a resist base composition onto the thin film, the base composition comprising an organic solvent and a base polymer; raising temperature of the resist base composition from a first temperature at which the temperature of the base film is lower than the boiling point of at least one of organic solvents to a second temperature at which the temperature thereof is higher than the temperature from which crosslinking is initiated, and then heating the base composition at the second temperature to form a resist base film 12 that is configured such that the molecular weight of the base polymer decreases from the thin film side toward the resist film side in the thickness direction; and applying a chemically amplified resist 13 onto the base film and then dissolving a low-molecular-weight region to form a mixture component where a component formed by dissolving the low-molecular-weight region is mixed with the component of a chemically amplified resist on an interface between the low-molecular weight region and the chemically amplified resist, and further heating the mixture component to form a mixture film 14.

Description

  The present invention relates to a mask blank manufacturing method and a transfer mask manufacturing method.

  In general, a semiconductor pattern is formed using a photolithography method in a manufacturing process of a semiconductor device or the like, and a transfer mask is used in a pattern transfer process when the photolithography method is performed. This transfer mask is manufactured by patterning a thin film (for example, a light-shielding film) provided on a substrate to form a desired transfer pattern. In patterning the transfer pattern, after forming a resist film on the thin film, the transfer pattern is formed using the resist film as a mask.

  In recent years, miniaturization has progressed in semiconductor patterns, and miniaturization has also progressed in transfer patterns of transfer masks used for forming semiconductor patterns. Therefore, in the mask blank, a chemically amplified resist suitable for the fine processing technique is used. The chemically amplified resist generates an acid by exposure, and the acid reacts with a functional group or a functional substance that controls the solubility of the polymer as a catalyst, thereby becoming a positive or negative resist. Since the chemically amplified resist has high sensitivity and resolution due to the acid-catalyzed reaction, a fine pattern can be formed.

  However, when a resist film made of a chemically amplified resist is formed directly on a thin film (for example, a light-shielding film) for forming a transfer pattern, there is a problem that the resist film is deactivated. Specifically, in the resist film, the solubility changes due to an acid catalytic reaction caused by exposure, but when the resist film is provided immediately above the light-shielding film, the acid catalytic reaction is inhibited. This is because when the thin film surface is formed of a transition metal compound, the oxidized transition metal compound is exposed on the surface, and the oxide adsorbs the basic component or generates the basic component in some form. This is thought to be caused by this. That is, the acid generated during exposure of the resist film is deactivated by inhibiting the reaction as a catalyst by the base component or diffusing to the light-shielding film side. In particular, this tendency is strong when chromium is contained in the thin film and the chromium oxide is exposed on the surface. As a result, in the resist film, the acid cannot sufficiently react during exposure, and the resolution when etched is lowered.

  Therefore, in order to suppress the influence of the base component contained in the light-shielding film, a method of providing a resist base film between the light-shielding film and the resist film has been proposed (see, for example, Patent Documents 1 and 2). . That is, a mask blank in which a light-shielding film, a resist base film, and a resist film are laminated in this order on a substrate has been proposed. This resist underlayer is interposed between the light-shielding film and the resist film, thereby allowing reaction between the base component contained in the light-shielding film and the acid generated in the resist film, or diffusion of the acid into the light-shielding film. Suppress. Thereby, the resolution of the pattern of the resist film can be improved. In addition, since the resist base film is made of an organic material, it has excellent adhesion to the light-shielding film and the resist film, and can maintain high adhesion of the resist film. The resist underlayer is not soluble in the developer used for forming a pattern on the resist film, but is patterned together by dry etching when etching the light-shielding film or the like using the resist film as a mask. Is done.

JP 2007-241259 A JP 2007-171520 A

  However, when providing a resist base film as in Patent Documents 1 and 2, when the resist film is developed, the resist film remains in a portion (space portion) of the resist base film exposed by the development, or the resist film is left behind. There was a problem that it reattached during cleaning. This occurs because the affinity between the resist base film and the resist film is high, and the resist film easily adheres to the resist base film. Such a residue of the resist film becomes a foreign substance when the light-shielding film is developed to form a transfer pattern, and thus a foreign substance defect occurs in the manufactured transfer mask. In the transfer mask, the pattern accuracy is lowered due to the foreign matter defect.

  Accordingly, the present invention provides a mask blank manufacturing method that has high adhesion to a resist film, and that foreign matter derived from the resist film hardly remains in the space portion during development, and that has less foreign matter defects, and a transfer mask that has excellent pattern accuracy. It aims at providing the manufacturing method of.

  As described above, the foreign substance defect generated when the mask blank is developed is caused by the foreign substance derived from the resist film remaining in the space portion. Specifically, the foreign substance defect occurs as shown in FIG. In the mask blank, the space portion 120 is removed by development of the resist film 113, and a part of the resist base film 112 is exposed. However, since the affinity between the component of the resist film 113 and the component of the resist base film 112 is high, the resist film 113 may remain as a foreign substance 130 at the end of the space portion 120. Further, the residue of the resist film 113 removed by development may reattach as foreign matter 130 on the space portion 120 during cleaning. These foreign matters 130 cause foreign matter defects in the transfer pattern when the transfer film is formed by etching the thin film 111 using the resist film 113 as a mask. For example, the foreign material 130 present at the end of the space portion 120 forms the pattern edge of the resist film 113 in an uneven shape, which may increase the line edge roughness of the transfer pattern. Further, for example, when cleaning is performed after development, the residue left in the resist film 113 is washed away by the cleaning liquid. However, when a droplet of the cleaning liquid remains on the substrate, the residual residue deposits due to volatilization of the cleaning liquid, and the foreign matter 130 in the space portion 120 or the like. May re-attach. In such a case, the foreign matter 130 is reattached along the flow of the cleaning liquid and causes a foreign matter defect.

  The inventors of the present invention have studied a method for suppressing foreign matter defects after development that occurs when a resist underlayer is provided on a mask blank and reducing foreign matter defects.

  As a result, when forming the resist underlayer film, the resist underlayer composition was polymerized by heating, and it was found that the temperature rise should be moderated at that time. In the resist base film formed by gently heating, the molecular weight decreases in the thickness direction, and a low molecular weight region having a low molecular weight is formed on the surface (surface on which the resist film is formed). When a chemically amplified resist is applied onto the low molecular weight region of the resist underlayer to form a resist film, a mixed film in which the components of the resist underlayer and the chemically amplified resist are mixed together is combined with the resist underlayer and the resist. It can be formed between the film. This mixed film contains a resist underlayer component that is insoluble in the developer, but since it contains a resist film component, the solubility in the developer changes upon exposure as in the case of the resist film. That is, when the mixed film contains a positive resist as a component of the resist film, it becomes insoluble in the developer when not exposed to light and becomes soluble in the developer when exposed. On the other hand, when the mixed film contains a negative resist, if it is not exposed, it becomes soluble in the developer, and the exposed region becomes insoluble.

In the mask blank provided with the mixed film, when the space portion of the resist film is dissolved and removed by development, the region located in the space portion of the resist film in the mixed film is also removed together. As a result, in the space portion, the mixed film under the resist film dissolves, so that the resist film rises and is removed from the mixed film. Therefore, in such a mask blank, when the resist film is developed, foreign matters derived from the resist film are suppressed from remaining in the space portion.
Moreover, since the mixed film contains the components of the resist underlayer film and the resist film, the mixed film is excellent in adhesion to each film. For this reason, the adhesiveness of the resist film to the substrate can be maintained.
Therefore, in such a mask blank, the remaining of foreign matters is reduced and foreign matter defects are suppressed, so that a transfer mask manufactured from this mask blank is excellent in pattern accuracy.

The present invention has been made based on the above findings and is as follows.
(Configuration 1)
The first configuration of the present invention is as follows.
A step of forming a thin film for forming a transfer pattern on a substrate, a step of applying a resist base composition containing one or more organic solvents and a base polymer on the thin film, and the resist base composition By heating the product from a first temperature lower than the boiling point of at least one kind of the organic solvent to a second temperature higher than the crosslinking start temperature of the resist base composition, and heating at the second temperature, Forming a resist underlayer having a low molecular weight region having a low molecular weight on the surface opposite to the thin film, the molecular weight of the base polymer decreasing in the thickness direction from the thin film side; and Applying a chemically amplified resist on the low molecular weight region of the resist underlayer, and dissolving the low molecular weight region with the chemically amplified resist, the low molecular weight region and the low molecular weight region Forming a mixed component in which the low molecular weight region dissolved component and the chemically amplified resist component are mixed at the interface with the chemically amplified resist, and heating the chemically amplified resist and the mixed component And a step of forming a mixed film interposed between the resist base film and the resist film together with the resist film.

(Configuration 2)
The second configuration of the present invention is as follows:
In the step of forming the resist underlayer, the mask blank manufacturing method according to the first configuration is such that the heating time for raising the temperature from the first temperature to the second temperature is 2 minutes or more.

(Configuration 3)
The third configuration of the present invention is:
The thickness of the said mixed film is a manufacturing method of the mask blank of the 1st or 2nd structure which is 0.1 nm or more and 10 nm or less.

(Configuration 4)
The fourth configuration of the present invention is as follows.
The said organic solvent is a manufacturing method of the mask blank in any one of the 1st-3rd structure containing at least 1 or more types of organic solvents whose boiling point is 100 degreeC or more.

(Configuration 5)
The fifth configuration of the present invention is:
The resist underlayer composition is a method for producing a mask blank of any one of the first to fourth configurations, which contains a crosslinking agent and has a crosslinking initiation temperature lower than at least one boiling point of the organic solvent.

(Configuration 6)
The sixth configuration of the present invention is as follows.
The resist underlayer composition contains a cross-linking catalyst and contains 0.05 to 10% by mass of the cross-linking catalyst with respect to 100% by mass of the base polymer. This is a method for manufacturing such a mask blank.

(Configuration 7)
The seventh configuration of the present invention is:
It is a manufacturing method of the transfer mask which forms a transfer pattern in the thin film of the mask blank manufactured by the method in any one of the 1st-the 6th composition.

  According to the present invention, it is possible to obtain a mask blank that has high adhesion to a resist film and that hardly causes foreign matters derived from the resist film to remain in the space during development, and has a high pattern accuracy. .

(A)-(e) is process drawing of the manufacturing method of the mask blank which concerns on one Embodiment of this invention. It is a schematic sectional drawing of the mask blank which concerns on one Embodiment of this invention. (A)-(d) is process drawing of the manufacturing method of the transfer mask which concerns on one Embodiment of this invention. It is a pixel histogram for demonstrating formation of a mixed film. 2 is a pixel histogram of a mask blank of Example 1. FIG. 10 is a pixel histogram of a mask blank of Comparative Example 1. It is a figure explaining the foreign material defect in a mask blank.

Hereinafter, an embodiment of the present invention will be described in the following order with reference to the drawings.
1. 1. Manufacturing method of mask blank 2. Mask blank 3. Transfer mask and manufacturing method thereof Effects of this embodiment

[1. Manufacturing method of mask blank]
A method for manufacturing a mask blank according to an embodiment of the present invention will be described with reference to FIGS. 1A to 1E are process diagrams of a method for manufacturing a mask blank according to an embodiment of the present invention.

  The manufacturing method of the mask blank 1 of this embodiment contains the process of forming the thin film 11 for forming a transfer pattern on the board | substrate 10, and 1 or more types of organic solvents and a base polymer on the thin film 11. FIG. A step of applying the resist underlayer composition 12 ′, and a step of applying the resist underlayer composition 12 ′ from a first temperature lower than the boiling point of at least one organic solvent to a second temperature higher than the crosslinking start temperature of the resist underlayer composition 12 ′. By heating up to the temperature and heating at the second temperature, the molecular weight of the base polymer decreases from the thin film 11 side in the thickness direction, and the molecular weight is low on the surface opposite to the thin film 11. A step of forming a resist underlayer 12 having a low molecular weight region 12a, and a chemical amplification type resist 13 'is applied on the low molecular weight region 12a of the resist underlayer 12 to form a chemically amplified resist 1 The low molecular weight region 12a is dissolved by ′ so that the dissolved component of the low molecular weight region 12a and the component of the chemically amplified resist 13 ′ are mixed at the interface between the low molecular weight region 12a and the chemically amplified resist 13 ′. The step of forming the component 14 ′, and the chemically amplified resist 13 ′ and the mixed component 14 ′ are heated to form the mixed film 14 interposed between the resist base film 12 and the resist film 13 together with the resist film 13. And a step of performing.

  Hereinafter, each process will be described.

(Formation process of the thin film 11)
First, the substrate 10 is prepared. The “substrate” here specifically includes a substrate of a transfer mask. Examples of the transfer mask include a transmissive mask blank such as a binary mask and a phase shift mask, and a reflective mask. In the case of a transmissive mask blank, the substrate is required to have translucency for the exposure wavelength to be used. For this reason, as a substrate material used for the binary mask and phase shift mask for ArF excimer laser exposure, for example, synthetic quartz glass is preferable, and a translucent substrate made of synthetic quartz glass or the like is used. On the other hand, in the case of a reflective mask, the substrate is required to have low thermal expansion. For this reason, the substrate material used for the reflective mask for EUV exposure is preferably, for example, a SiO ₂ —TiO ₂ -based low expansion glass, such as a low expansion glass substrate containing titania.

  Subsequently, as shown in FIG. 1A, a thin film 11 for forming a transfer pattern is formed on the substrate 10 by sputtering, for example. The “thin film” here refers to a thin film on which a mask pattern of a transfer mask is formed. Typical examples include a thin film including a light shielding film when the transfer mask is a binary mask, and a thin film including a light semi-transmissive film when the transfer mask is a halftone phase shift mask film. In some cases, a thin film including a multilayer reflective film may be used. The thin film includes, for example, a hard mask film, an etching mask film necessary for pattern formation, an absorber film in the case of a reflective mask, and a thin film including various functional films in the concept of “thin film”. included.

  When a binary mask blank is manufactured, a light shielding film is formed on the substrate 10 as the thin film 11. Further, a phase shift mask blank can be obtained by forming a phase shift film, or a phase shift film and a light shielding film as the transfer pattern forming thin film 11 on the surface of the substrate 10. The thin film 11 may be a single layer or a plurality of layers (for example, a laminated structure of a light shielding layer and an antireflection layer). Further, when the light shielding film has a laminated structure of a light shielding layer and an antireflection layer, the light shielding layer may be composed of a plurality of layers. Further, the phase shift film and the etching mask film may be a single layer or a plurality of layers.

  For example, a binary mask blank including a light shielding film formed of a material containing chromium (Cr), a binary mask blank including a light shielding film formed of a material containing a transition metal and silicon (Si), and tantalum (Ta ) Including a binary mask blank provided with a light shielding film formed of a material containing), a phase containing a phase shift film formed of a material containing silicon (Si), or a material containing transition metal and silicon (Si) A shift type mask blank etc. are mentioned. Examples of the material containing the transition metal and silicon (Si) include a material containing at least one element of nitrogen, oxygen and carbon in addition to the transition metal and silicon in addition to the material containing the transition metal and silicon. It is done. Specifically, a transition metal silicide or a material containing a transition metal silicide nitride, oxide, carbide, oxynitride, carbonate, or carbonitride is preferable. As the transition metal, molybdenum, tantalum, tungsten, titanium, chromium, hafnium, nickel, vanadium, zirconium, ruthenium, rhodium, niobium, and the like are applicable. Of these, molybdenum is particularly preferred.

  Further, in the binary mask blank or the phase shift mask blank, an etching mask film may be provided on the light shielding film. The material of the etching mask film is selected from materials that are resistant to the etchant used when patterning the light shielding film. When the material of the light shielding film is a material containing chromium (Cr), for example, the material containing silicon (Si) is selected as the material of the etching mask film. Further, when the material of the light shielding film is a material containing silicon (Si) or a material containing a transition metal and silicon (Si), as the material of the etching mask film, for example, the material containing chromium (Cr) is used. Selected.

  Moreover, when manufacturing a reflective mask blank, a thin film including a multilayer reflective film is formed. Specifically, a high refractive index layer made of a silicon film (Si) and a low refractive index layer made of a molybdenum film are alternately formed into a pair of a high refractive index layer and a low refractive index layer by ion beam sputtering. In this example, a multilayer reflective film obtained by stacking 40 pairs and a thin film having a protective film made of ruthenium (Ru) are formed on the multilayer reflective film by ion beam sputtering.

(Application process of resist underlayer composition 12 ')
Next, a resist base composition 12 ′ is applied on the thin film 11 by, for example, spin coating. The resist underlayer composition 12 'contains a base polymer, a crosslinking agent, a crosslinking catalyst, and one or more organic solvents. In the resist underlayer composition 12 ′, a base polymer, other cross-linking agent, and the like are dissolved in an organic solvent. The base polymer generally has a varied molecular weight, and contains a component having a relatively large molecular weight (high molecular weight component) and a component having a relatively small molecular weight (low molecular weight component). As will be described later, the resist underlayer composition 12 ′ is heated to remove the organic solvent, and at the same time, the base polymer is crosslinked with a crosslinking agent, thereby forming the resist underlayer film 12.

(Process for forming resist underlayer 12)
Next, as shown in FIG.1 (c), resist base composition 12 'apply | coated on the thin film 11 is heated. By heating, the organic solvent contained in the resist underlayer composition 12 ′ is removed, and at the same time, the base polymer is crosslinked to form the resist underlayer film 12.

  In this embodiment, when heating the resist base composition 12 ′, the temperature is raised from a first temperature lower than the boiling point of at least one organic solvent to a second temperature higher than the crosslinking start temperature of the resist base composition 12 ′. And heating at the second temperature. Then, when the temperature reaches the second temperature, the temperature rise is stopped and the second temperature is heated for a predetermined time. As a result, the crosslinking proceeds, and finally the organic solvent is completely volatilized to form the resist base film 12. The first temperature is a temperature at which the resist base composition 12 ′ starts to be heated, and is a temperature lower than the boiling point of at least one organic solvent contained in the resist base composition 12 ′. The second temperature is a temperature after the temperature is raised, which is higher than the crosslinking start temperature of the resist base composition 12 ′ and is equal to or higher than the boiling point of the organic solvent. That is, in the present embodiment, the temperature is raised from a low temperature (first temperature) at which the organic solvent does not volatilize to a high temperature (second temperature) at which the crosslinking reaction proceeds, and is heated at the second temperature. To do. For example, in the case of using a resist underlayer composition in which the boiling point of the organic solvent is 120 ° C. and the crosslinking start temperature is 120 ° C., the temperature raising time is set to 4 from 20 ° C. (first temperature) to 200 ° C. (second temperature). Heat in minutes. When the temperature reaches 200 ° C., the temperature rise is stopped and heating is performed at 200 ° C. for a predetermined time. By gently heating from such a low temperature, the molecular weight decreases from the thin film 11 side in the thickness direction, and the low molecular weight region 12a having a low molecular weight is provided on the surface opposite to the thin film 11. A resist underlayer 12 can be formed.

  Here, heating of the resist underlayer composition 12 ′ and formation of the low molecular weight region 12 a in the resist underlayer film 12 will be described.

  Conventionally, when a resist undercoating composition is heated, the substrate on which the resist undercoating composition has been applied is placed in an environment at a high temperature (for example, 200 ° C.) higher than the crosslinking start temperature and rapidly heated. That is, from the beginning, the resist underlayer composition was heated in a relatively high temperature environment. In this case, the organic solvent is quickly removed under a high temperature environment, and a film is formed in a state where the low molecular weight component and the high molecular weight component of the base polymer are mixed. Thereafter, crosslinking (polymerization) of the base polymer in the film proceeds. As a result, the resist underlayer film formed by crosslinking is a film having a small variation in the crosslinked state (polymerization state) and a small variation in molecular weight. Therefore, the resist base film formed by rapid heating is a film having a relatively high molecular weight in the thickness direction.

  On the other hand, in this embodiment, instead of heating at a high temperature from beginning to end, the resist underlayer composition 12 ′ is heated from a first temperature (for example, 20 ° C.) to a second temperature (for example, 200 ° C.). And heat gently. In this case, since the organic solvent is not removed immediately, the crosslinking reaction proceeds in the presence of the organic solvent (not completely removed). That is, the base polymer starts to be crosslinked (polymerized) while being dissolved in the organic solvent. At this time, among the base polymer dissolved in the organic solvent, the high molecular weight component starts to crosslink and coagulate rather than the low molecular weight component. This is because when the high molecular weight component is polymerized, the molecules become enormous and some of the enormous molecules come into contact with and be adsorbed on the coated surface (thin film 11). That is, the high molecular weight component immediately loses the degree of freedom of dissolution in the organic solvent and aggregates downward. This occurs repeatedly, and a film in which the high molecular weight component is cross-linked is formed from the lower side (the thin film 11 side) by coagulation of the high molecular weight component. On the other hand, although the low molecular weight component does not crosslink, the dissolved state in the organic solvent is easily maintained, and the dissolved low molecular weight component oozes out above the film together with the organic solvent. As the temperature rises over the course of the heating time, low molecular weight components also begin to coagulate due to crosslinking. By this coagulation, a film in which low molecular weight components are cross-linked is formed in a laminated manner. Finally, the organic solvent is volatilized and the resist underlayer film 12 is formed. Thus, the resist underlayer 12 is formed by laminating a film in which a low molecular weight component is crosslinked on a film in which a high molecular weight component is crosslinked. A film having a high molecular weight component cross-linked is cross-linked in an environment rich in a cross-linking agent at the initial stage of heating, and thus has a high degree of cross-linking and is polymerized. On the other hand, a film in which a low molecular weight component is cross-linked is cross-linked in an environment where the cross-linking agent has been consumed and the cross-linking agent has been consumed (the amount of the cross-linking agent is small). . Therefore, the resist underlayer 12 is configured such that the molecular weight decreases in the thickness direction from the thin film 11 side, and a low molecular weight region 12a having a low molecular weight is provided on the surface opposite to the thin film 11 (resist film 13 side). Will be formed.

  As will be described later, the low molecular weight region 12a of the resist underlayer 12 is dissolved by the applied chemically amplified resist 13 '. Then, the mixed component 14 'is formed by mixing with the components of the chemically amplified resist 13' by dissolution. The low molecular weight region 12a is a low molecular weight region that dissolves in the chemically amplified resist 13 'and indicates a region having a predetermined thickness from the surface of the resist base film 12 on the resist film 13 side.

In this embodiment, when forming the resist underlayer 12, as described above, the resist underlayer composition 12 ′ is heated and gently heated, and crosslinked so as not to completely evaporate the organic solvent. Yes. For this reason, from the viewpoint of suppressing the volatilization of the organic solvent, it is preferable to heat at a moderate temperature increase rate when the temperature is increased from the first temperature to the second temperature. Specifically, heating is preferably performed at a temperature rising rate of 80 ° C./min or less, and heating is preferably performed at a temperature rising rate of 50 ° C./min or less. When the rate of temperature rise exceeds 80 ° C./min, the crosslinking reaction proceeds quickly, and the entire layer is in a uniform crosslinked state before the low molecular weight components gather at the top. Note that the rate of temperature increase need not be constant, but it is preferably a rate of temperature increase enough to disperse the low molecular weight component in the vicinity of the crosslinking start temperature.
As for the temperature raising time, it is preferable that the time from the first temperature to the second temperature is at least 2 minutes from the start of overheating, from the viewpoint of allowing the crosslinking reaction to proceed slowly. The upper limit of the temperature raising time is not particularly limited, but is preferably 30 minutes or less, particularly preferably 10 minutes or less. Even if heating is performed for 30 minutes or more, no particular change is observed in the formation state of the mixed film. Considering the time schedule of the process, the temperature raising time is preferably within 10 minutes.

  Further, from the viewpoint of suppressing the volatilization of the organic solvent when the resist base composition 12 'is heated, the boiling point of the organic solvent contained in the resist base composition is preferably higher than the crosslinking start temperature. This is because by increasing the boiling point, volatilization of the organic solvent during the temperature rise is suppressed, and the low molecular weight region 12a is easily formed. The boiling point of the organic solvent is preferably at least 100 ° C. or higher, more preferably 115 ° C. or higher and 180 ° C. or lower. When the boiling point is less than 100 ° C., the organic solvent volatilizes quickly, and there is a possibility that the molecular weight distribution does not occur well in the formed resist underlayer. On the other hand, if the boiling point exceeds 180 ° C., the organic solvent is volatilized and heated for a long time at a high temperature, which may overheat the base polymer.

  Examples of such an organic solvent include ketones such as cyclohexanone (boiling point 155 ° C.), 3-methoxybutanol (boiling point 158 ° C.), 3-methyl-3-methoxybutanol (boiling point 173 ° C.), PGME (1-methoxy- 2-propanol) (boiling point 118 ° C.), ethylene glycol monomethyl ether (boiling point 124.5 ° C.), propylene glycol monoethyl ether (boiling point 132 ° C.), diethylene glycol dimethyl ether (boiling point 162 ° C.) and other alcohols and ethers, PGMEA ( And esters such as 2- (1-methoxy) propyl acetate) (boiling point 146 ° C.), ethyl lactate (boiling point 155 ° C.), butyl acetate (boiling point 126 ° C.), and methyl 3-methoxypropionate (boiling point 143 ° C.). , One or more of these can be used in combination, The present invention is not limited to these. In the present invention, for example, PGME (1-methoxy-2-propanol), PGMEA (2- (1-methoxy) propyl acetate) and the like can be preferably used. In addition, when using the organic solvent of a mixed solvent, at least 1 organic solvent is the bridge | crosslinking start temperature vicinity of a resist base composition (For example, when bridge | crosslinking start temperature is set to T degreeC, it is the range of T-10 degreeC-T + 3 degreeC). It is good to mix a thing in the ratio of 10-60 mass%, Preferably 25-50 mass%. Use of such a mixed solvent is preferable because the reaction rate near the crosslinking start temperature continues to be low due to the volatilization of the solvent component and the low molecular weight component of the base polymer is pushed up to the upper part of the layer.

  In addition, from the viewpoint of heating so that the organic solvent does not volatilize, the crosslinking initiation temperature of the resist base composition may be lower than the boiling point of the organic solvent (at least one organic solvent in the case of a mixed solvent). You may crosslink under. The crosslinking initiation temperature varies depending on the type of base polymer and crosslinking agent. For example, when a mixed solvent of PGM (boiling point 118 ° C.) and PGMEA (boiling point 146 ° C.) is used, the crosslinking initiation temperature is not particularly limited, but is preferably 145 ° C. or less, preferably 100 ° C. or more and 125 ° C. or less. It is particularly preferable that there is no particular limitation as long as the system has such a crosslinking initiation temperature.

Further, the resist underlayer composition contains a crosslinking catalyst, and when the base polymer is a novolac resin, an acidic catalyst is selected. Examples of the acidic catalyst include organic acids such as sulfonic acids such as paratoluenesulfonic acid and carboxylic acids such as benzoic acid, and inorganic acids such as hydrochloric acid and sulfuric acid. Organic acids are preferred. In addition, a photoacid generator such as 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine is mixed, and an acid generated by light irradiation is used as a catalyst. You can also.
The cross-linking reaction rate varies depending on the type of cross-linking catalyst and the pH of the resist underlayer composition liquid. For this reason, it is considered that the thickness of the low molecular weight region 12a also varies depending on the type and content of the crosslinking catalyst. Specifically, when the crosslinking reaction rate is high (for example, the content of the crosslinking catalyst is large), the low molecular weight component is likely to coagulate together with the high molecular weight component, so that the variation in molecular weight is small and the low molecular weight region 12a. The thickness decreases. On the other hand, when the reaction rate is slow (for example, the content is low), the low molecular weight component is less likely to coagulate, and the thickness of the low molecular weight region 12a increases. From this, the resist base composition contains 0.05% by mass to 10% by mass, preferably 0.05% by mass to 3% by mass of the crosslinking catalyst with respect to 100% by mass of the base polymer. . If the amount of the crosslinking catalyst is too large relative to the base polymer, it is difficult to form a molecular weight distribution of the base polymer above and below the membrane. In addition, if the amount of the crosslinking catalyst is too small, the region of the low molecular weight component that is not crosslinked (the portion that melts with the resist layer) becomes too thick, and the resolution accuracy when the resist pattern is formed may deteriorate. Occurs. Thereby, the thickness of the mixed film 14 can be formed to 0.1 nm or more and 10 nm or less, for example.

  In addition, it does not specifically limit as a base polymer in a resist base composition, A well-known base polymer can be used. Examples of the base polymer include novolac resins and acrylic resins.

(Coating process of chemically amplified resist 13 ')
Next, as shown in FIG. 1D, a chemically amplified resist 13 'is applied on the resist underlayer 12 by, for example, spin coating. As described above, the low molecular weight region 12a having a low molecular weight is formed on the coating surface of the resist base film 12 on which the chemically amplified resist 13 'is applied. The chemically amplified resist 13' has a low molecular weight region 12a. It is applied to cover. At this time, the low molecular weight region 12a is dissolved by the chemically amplified resist 13 '. As a result, at the interface between the low molecular weight region 12a and the applied chemically amplified resist 13 ', the dissolved component of the low molecular weight region 12a and the component of the chemically amplified resist 13' are mixed, and the mixed component 14 'is mixed. Will be formed. That is, a layer of the mixed component 14 ′ and the chemically amplified resist 13 ′ is formed on the resist base film 12.

(Process for forming resist film 13 and mixed film 14)
Next, as shown in FIG. 1E, the chemically amplified resist 13 'is heated to form a resist film 13. At this time, since the mixed component 14 ′ is also heated at the same time, the mixed film 14 interposed between the resist base film 12 and the resist film 13 is formed.

  The mask blank 1 of this embodiment is obtained by the above.

[2. Mask blank]
Next, a mask blank 1 according to an embodiment of the present invention will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view of a mask blank according to an embodiment of the present invention.

  As shown in FIG. 2, the mask blank 1 according to the present embodiment includes a thin film 11, a resist base film 12, and a resist film 13 on a substrate 10, and the resist base film 12 and the resist film 13 are interposed between them. A mixed film 14 is formed so as to intervene.

  The resist base film 12 is provided on the thin film 11, and the influence of chromium oxide or the like contained in the thin film 11 is reduced to suppress deactivation of the resist film 13 provided on the resist base film 12. The resist underlayer 12 is not dissolved (has resistance) to the developer used when forming a pattern on the resist film 13, but the thin film 11 is dry-etched using the resist film 13 as a mask.

  The resist film 13 is provided on the resist base film 12 via the mixed film 14. When the resist film 13 is manufactured to the transfer mask 50, a predetermined resist pattern is formed and becomes a mask for patterning the thin film 11.

  The mixed film 14 is provided so as to be interposed between the resist base film 12 and the resist film 13. Although the mixed film 14 includes the component of the resist underlayer film 12, the mixed film 14 includes the component of the resist film 13. For example, when the resist film 13 is a positive resist, the mixed film 14 contains a positive resist component. This mixed film 14 has the same solubility as the positive resist in the developer, and the unexposed area becomes insoluble in the developer, and the exposed area becomes soluble in the developer. When the resist film 13 is a negative resist, the mixed film 14 contains a negative resist component, so that the unexposed region of the mixed film 14 becomes soluble in the developer and is exposed. The area becomes insoluble in the developer.

  Such a mixed film 14 is removed together with the resist film 13 when the resist film 13 is developed. Specifically, as shown in FIG. 3B described later, when the resist film 13 is developed, the space portion 20 is removed and a resist pattern is formed. At this time, the region of the space portion 20 of the mixed film 14 is also removed. Thereby, in the region of the space portion 20, the mixed film 14 under the resist film 13 is dissolved and removed, so that the resist film 13 is lifted and removed so as to be removed from the mixed film 14. Become. That is, the mixed film 14 dissolves during development, so that the upper resist film 13 is lifted and removed from the space portion 20 (lift-off effect). Therefore, according to the mixed film 14, it is possible to suppress the foreign matters derived from the resist film 13 from remaining in the space portion 20. Since the region of the line portion of the resist pattern of the mixed film 14 is insoluble in the developer, the resist pattern of the resist film 13 is not lifted off by the developer.

  Further, since the mixed film 14 contains the components of the resist film 13, the mixed film 14 has good wettability with respect to the developing solution and is excellent in the permeability of the developing solution. In addition, since the mixed film 14 is formed of an organic material, the mixed film 14 has excellent adhesion to the resist base film 12 and the resist film 13, and can maintain high adhesion of the resist film 13 to the mask blank 1. it can.

  The thickness of the mixed film 14 corresponds to the thickness of the low molecular weight region 12a. The thickness of the mixed film 14 increases as the thickness of the low molecular weight region 12a increases. The thickness of the mixed film 14 is not particularly limited, but is preferably 0.1 nm or more and 10 nm or less.

[3. Transfer mask and manufacturing method thereof]
Next, the transfer mask and the manufacturing method thereof according to the present embodiment will be described with reference to FIGS. FIGS. 3A to 3D are process diagrams showing a manufacturing process of a transfer mask according to an embodiment of the present invention.

  The transfer mask of this embodiment is manufactured by forming a predetermined pattern shape on the above-described mask blank. Below, the case where the resist film 13 contains a positive resist component is demonstrated.

  First, as shown in FIG. 3A, the mask blank 1 is exposed so as to correspond to a predetermined pattern. By exposure, the exposed portions of the resist film 13 and the mixed film 14 become soluble in the developer.

Subsequently, as shown in FIG. 3B, the mask blank 1 is developed. By developing, a region corresponding to the space portion 20 in the resist film 13 and the mixed film 14 is removed to form a predetermined resist pattern. In this development, since the affinity between the component derived from the resist film 13 and the resist base film 12 is high, the component derived from the resist film 13 may remain in the space portion 20 of the resist pattern. Further, the residue of the resist film 13 removed by the development is dispersed in the cleaning liquid or the like. However, if the cleaning liquid droplets or the like remain on the substrate surface, the residue of the cleaning liquid is deposited due to volatilization of the cleaning liquid. There is a risk of reattachment.
However, in the present embodiment, the mixed film 14 is provided so as to be interposed between the resist underlayer film 12 and the resist film 13, and the mixed film 14 dissolves in the developing solution, thereby removing the resist film 13. (Lift-off effect). As a result, the foreign matter derived from the resist film 13 is removed from the space portion 20 together with the mixed film 14, and the remaining foreign matter is suppressed in the space portion 20. Further, in the space portion 20 from which the mixed film 14 has been removed, most of the residue from the resist film 13 is removed from the substrate together with the developer. Since the number of resist films 13 remaining on the substrate 10 at the stage of the cleaning process is small, redeposition is suppressed in the cleaning process. For this reason, the resist film 13 is excellent in resolution and excellent in the line edge roughness of the space portion 20.

  In the mixed film 14 containing a positive resist component, the exposed area is soluble in the developer, and the unexposed area is insoluble in the developer. When the mixed film 14 is developed, only the exposed area of the mixed film 14 is scraped off in the thickness direction. That is, the mixed film 14 is not scraped away from the space portion 20 in the surface direction. For this reason, the adhesiveness of the resist film 13 that remains without being exposed to the resist base film 12 is not impaired.

  Subsequently, as shown in FIG. 3C, the resist base film 12 and the thin film 11 are etched using the resist film 13 on which a predetermined resist pattern is formed as a mask. A predetermined transfer pattern is formed on the thin film 11 by etching. Then, as shown in FIG. 3D, the transfer mask 50 of this embodiment is obtained by removing the resist film 13 and the like. Since the transfer pattern of the transfer mask 50 is formed with a resist pattern with little remaining foreign matter, foreign matter defects are reduced. Moreover, it has excellent line edge roughness. Therefore, the transfer mask 50 of this embodiment is excellent in pattern accuracy.

  In the present embodiment, the case where the resist film 13 contains a positive resist component has been described, but the present invention is not limited to this. Even if the resist film 13 contains a negative resist component, the same effect can be obtained.

[4. Effects of this embodiment]
According to the present embodiment, one or more effects shown below are produced.

  According to the method of this embodiment, the resist underlayer composition 12 ′ is raised from a low temperature (first temperature) at which the organic solvent does not volatilize to a high temperature (second temperature) at which the crosslinking reaction proceeds. The resist base film 12 having the low molecular weight region 12a is formed by heating and heating at the second temperature. Then, a chemically amplified resist 13 ′ is applied to the low molecular weight region 12 a to form a resist film 13, whereby a mixed film 14 containing these components is formed at the interface between the resist base film 12 and the resist film 13. Forming. This mixed film 14 exhibits the same solubility as the resist film 13 in the developer, and is excellent in the permeability of the developer. Therefore, when the resist film 13 is developed, the mixed film 14 is dissolved, so that the resist film 13 as an upper layer can be floated and the resist film 13 can be removed from the space portion 20. Therefore, according to the manufacturing method of the present embodiment, when the resist film 13 is developed, the residue of foreign matters derived from the resist film 13 in the space portion 20 is reduced, and the mask blank 1 with few foreign matter defects can be obtained.

  Further, in the space portion 20 from which the mixed film 14 has been removed, the remaining of developer droplets and the like in which the residue of the resist film 13 after development is dispersed is suppressed. In other words, the residue is discharged out of the substrate together with the developer, and reattachment to the space portion 20 is suppressed. Therefore, according to the mask blank 1, when the resist film 13 is developed, the remaining foreign matter such as missing particles is reduced, so that foreign matter defects are reduced. For example, in spin cleaning or the like, there is a possibility that a vortex-like foreign substance defect may occur due to the re-attachment of the fallen residue in a vortex shape, which can be suppressed according to the present embodiment.

  The mixed film 14 is formed of a mixed component in which the components of the resist underlayer film 12 and the resist film 13 are mixed. For this reason, the mixed film 14 is excellent in adhesiveness with the resist underlayer film 12 and the resist film 13, and can maintain high adhesiveness of the resist film 13 to the mask blank 1.

  In the transfer mask 50 of this embodiment, foreign matter defects are suppressed, and the transfer pattern is excellent in line edge roughness. For this reason, the transfer mask 50 is excellent in pattern accuracy.

  Hereinafter, although this invention is demonstrated based on a more detailed Example, this invention is not limited to these Examples.

<Example 1>
In this example, a halftone phase shift mask blank and a transfer mask were manufactured and evaluated for each.

(Manufacture of mask blanks)
First, a light semi-transmissive film, a light-shielding film, and a hard mask were formed as thin films on a light-transmitting substrate made of synthetic quartz glass by sputtering. Specifically, a single-layer MoSiN film (thickness: 69 nm) was formed as a light semi-transmissive film on a transparent substrate. Specifically, using a mixed target of molybdenum (Mo) and silicon (Si) (Mo: Si = 10 mol%: 90 mol%), a mixed gas atmosphere of argon (Ar), nitrogen (N ₂ ), and helium (He) (Gas flow ratio Ar: N2: He = 5: 49: 46), gas pressure of 0.3 Pa, DC power supply power of 3.0 kW, and reactive sputtering (DC sputtering) made of molybdenum, silicon and nitrogen A MoSiN film was formed with a thickness of 69 nm. Next, the glass substrate on which the MoSiN film was formed was subjected to a heat treatment using a heating furnace in the atmosphere at a heating temperature of 450 ° C. and a heating time of 1 hour. This MoSiN film had an transmittance of 6.16% and a phase difference of 184.4 degrees in an ArF excimer laser.
Subsequently, three layers of a CrOCN layer (thickness 30 nm), a CrN layer (thickness 4 nm), and a CrOCN layer (thickness 14 nm) were formed in this order as a light-shielding film. Specifically, a chromium (Cr) target is used as a sputtering target, and a mixed gas atmosphere of argon (Ar), carbon dioxide (CO ₂ ), nitrogen (N 2), and helium (He) (gas pressure 0.2 Pa, gas flow ratio) Ar: CO2: N2: He = 20: 35: 10: 30), the power of the DC power source was 1.7 kW, and a 30 nm thick CrOCN layer was formed by reactive sputtering (DC sputtering). Subsequently, a mixed gas atmosphere of argon (Ar) and nitrogen (N ₂ ) (gas pressure 0.1 Pa, gas flow rate ratio Ar: N 2 = 25: 5) was set, and the power of the DC power source was set to 1.7 kW. A CrN layer having a thickness of 4 nm was formed by sputtering (DC sputtering). Finally, a mixed gas atmosphere of argon (Ar), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), and helium (He) (gas pressure 0.2 Pa, gas flow ratio Ar: CO 2: N 2: He = 20: 35: 5: 30), the power of the DC power supply is 1.7 kW, and a CrOCN layer having a film thickness of 14 nm is formed by reactive sputtering (DC sputtering). A light shielding film was formed.
This light-shielding film has a laminated structure with the light semi-transmissive film and is adjusted so that the optical density (OD) is 3.0 at a wavelength of 193 nm of ArF excimer laser exposure light. The surface reflectance of the light shielding film with respect to the wavelength of the exposure light was 20%.
And the HMDS process was performed on the surface of the formed thin film on predetermined conditions.

Next, a resist underlayer composition was applied onto the thin film by a spin coating method. The resist base composition used here contains the following components.
Base polymer: Novolac polymer Organic solvent: Mixed solvent of 1-methoxy-2-propanol (PGME) (boiling point 118 ° C.) and 2- (1-methoxy) propyl acetate (PGMEA) (boiling point 146 ° C.) Crosslinking agent : Alkoxymethylmelamine-based crosslinking agent / crosslinking catalyst: Sulphonic acid-based acidic catalyst / crosslinking start temperature: 115 ° C

  Thereafter, the resist underlayer composition (thickness 10 nm) was formed by heat-crosslinking the resist underlayer composition under predetermined conditions. It took 4 minutes to raise the temperature from room temperature (20 ° C.) to 200 ° C., followed by 6 minutes of heat treatment. Thereby, a resist underlayer having a low molecular weight region on the surface side was formed.

  Next, a chemically amplified resist (“SLV12M negative resist” manufactured by Fuji Film Electronics Materials Co., Ltd.) was applied onto the low molecular weight region of the resist underlayer by spin coating. By applying the chemically amplified resist, a mixed component is formed by dissolving the low molecular weight region at the interface between the low molecular weight region and the resist underlayer. Then, the resist film (thickness 160nm) was formed by heating at 130 degreeC for 10 minute (s). Simultaneously with the formation of the resist film, a mixed film interposed between the resist underlayer film and the resist film was formed. Thereby, the mask blank of Example 1 was obtained.

(Manufacture of transfer masks)
Subsequently, a predetermined transfer pattern was formed on the obtained mask blank of Example 1 to manufacture a transfer mask. Specifically, the mask blank was exposed to an electron beam and baked at 120 ° C. after the exposure. Then, the transfer pattern was formed by developing using a developing solution (tetramethylamino hydride (TMAH) aqueous solution). The width of the transfer pattern (space portion width) was set to 100 nm.

(Evaluation method)
The mixed film, mask blank and transfer mask were evaluated by the following methods.

  Whether or not a mixed film was formed was confirmed as follows. A chemically amplified resist was dropped on the resist underlayer formed under the above heating conditions, and this was heated and crosslinked to form a resist film. Then, the resist film is developed, and, for example, as shown in the pixel histogram of FIG. 4, in the resist film, the region where the chemically amplified resist is dropped (region T indicated by the arrow in the figure) is removed in a circular shape. It was confirmed. The circular shape indicates that the resist base film is dissolved by the chemically amplified resist and a mixed film of these components is formed.

  In order to measure the thickness of the mixed film, the developed mask blank is developed multiple times, and the amount of decrease in thickness (thickness reduction) when components such as resist film no longer elute into the developer. It was measured. Since the mixed film is scraped off by development, the amount of decrease in thickness due to development corresponds to the thickness of the mixed film.

The resolution was evaluated by forming an isolated line pattern (IL line: space = 1:> 100).
First, the electron beam irradiation was performed with respect to the formed resist layer using the electron beam irradiation apparatus. Immediately after irradiation, it was heated on a hot plate at 120 ° C. for 10 minutes. Then, it developed using TMAH with a density | concentration of 2.38 mass%, rinsed using the pure water, and was made to dry. In this way, an isolated line pattern (IL line: space = 1:> 100) was formed. The exposure dose was 35 μC / cm 2. The case where a line having a pattern dimension of 60 nm could be formed was evaluated as acceptable (◯), and the case where the pattern dimension was not formed was determined as unacceptable (x).

  The foreign matter defect was evaluated by the number of defects of the manufactured transfer mask. Measure the pixel histogram by optical measurement method. If defects (pixels) of 200 nm or more are formed in high density and geometric shape, it is rejected (x). If the defects are dispersed at low density, it passes. (○).

(Evaluation results)
In Example 1, formation of the mixed film was confirmed. The thickness was confirmed to be 4.87 nm because the amount of film reduction was 4.87 nm. Further, as shown in the pixel histogram of FIG. 5, it was confirmed that the foreign matter defects were low density and few. This is presumably because resist residue and the like were flowed together with the developer at the development stage, and the number of resist residue remaining on the substrate was small at the washing stage.
The evaluation results are shown in Table 1 below.

<Comparative example 1>
In Comparative Example 1, the same procedure as in Example 1 was performed except that the heating condition of the resist underlayer composition was changed. Specifically, the resist base composition was rapidly heated at 200 ° C. and heated at 200 ° C. for 10 minutes.
As shown in Table 1, in Comparative Example 1, since the low molecular weight region is not formed in the resist underlayer film, the resist film remains in the pattern portion or the residue from the resist film is reattached. It was confirmed that there are many.
In addition, as shown in the pixel histogram of FIG. 6, foreign object defects were detected radially from the center of the substrate. The reason is considered as follows. After forming the pattern, the substrate was washed with a cleaning solution, and the cleaning solution was shaken off by spin rotation and dried. At this time, residue of the resist film is dispersed in the cleaning liquid supplied onto the substrate. It is considered that the droplets of the cleaning liquid were dried without being shaken on the substrate, so that the residue of the resist film contained in the droplets formed a radial locus and deposited on the substrate.

<Comparative example 2>
Comparative Example 2 was manufactured in the same manner as in Example 1 except that a resist film was directly formed on a thin film without forming a resist base film.
As shown in Table 1, in Comparative Example 2, since no resist underlayer was formed, no increase in foreign matter defects due to the remaining resist underlayer was confirmed. However, it was confirmed that the resolution was inferior because the resist film was deactivated.

<Examples 2 and 3>
Examples 2 and 3 were produced in the same manner as Example 1 except that the content of the crosslinking catalyst contained in the resist underlayer composition was changed. Specifically, the content of the crosslinking catalyst was twice that of Example 1 in Example 2 and half that of Example 1 in Example 3.
As shown in Table 1, in Examples 2 and 3, as in Example 1, it was confirmed that the resolution was excellent and there were few foreign object defects. In Examples 2 and 3, it was confirmed that the content of the crosslinking catalyst was changed and the thickness of the mixed film was different. Specifically, it was confirmed that the thickness of the mixed film was 0.6 nm in Example 2 and 4.8 nm in Example 3.

  As described above, according to the present invention, by providing a mixed film, a mask blank having high adhesion to the resist film and having less foreign matter defects due to the foreign matter originating from the resist film being difficult to remain in the space during development is obtained. It is done. From this mask blank, a transfer mask having excellent pattern accuracy can be obtained.

In the above-described embodiments, the halftone phase shift mask blank and the method of manufacturing the halftone phase shift mask using the molybdenum nitride silicide thin film as the light semi-transmissive film have been described. However, the technical scope of the present invention is described above. It is not limited to the configuration of
For example, a halftone phase shift mask using a light semi-transmissive film mainly composed of other constituent elements, a Levenson type phase shift mask, a binary mask using molybdenum silicide as a light shielding film, a binary mask using a chromium-based light shielding film, etc. The present invention can also be applied to the manufacture of a transmission type transfer mask. Furthermore, the technique of the present invention can also be applied to the manufacture of a reflective mask that uses EUV as exposure light.

DESCRIPTION OF SYMBOLS 1 Mask blank 10 Substrate 11 Thin film 12 Resist base film 12a Low molecular weight area | region 13 Resist film 14 Mixed film 20 Space part 50 Transfer mask

Claims (7)

Forming a thin film for forming a transfer pattern on the substrate;
Applying a resist base composition containing at least one organic solvent and a base polymer on the thin film;
The resist underlayer composition is heated from a first temperature lower than at least one boiling point of the organic solvent to a second temperature higher than a crosslinking start temperature of the resist underlayer composition, and heated at the second temperature. By doing so, the molecular weight of the base polymer is decreased in the thickness direction from the thin film side, and a resist underlayer film having a low molecular weight region having a low molecular weight is formed on the surface opposite to the thin film. Process,
A chemical amplification resist is applied on the low molecular weight region of the resist underlayer, and the low molecular weight region is dissolved by the chemical amplification resist, so that an interface between the low molecular weight region and the chemical amplification resist is formed. Forming a mixed component in which the dissolved component of the low molecular weight region and the component of the chemically amplified resist are mixed;
Forming a mixed film interposed between the resist base film and the resist film together with a resist film by heating the chemically amplified resist and the mixed component.   The method of manufacturing a mask blank according to claim 1, wherein in the step of forming the resist base film, a heating time for raising the temperature from the first temperature to the second temperature is 2 minutes or more.   The method of manufacturing a mask blank according to claim 1 or 2, wherein the thickness of the mixed film is 0.1 nm or more and 10 nm or less.   The said organic solvent is a manufacturing method of the mask blank in any one of Claims 1-3 containing at least 1 or more types of organic solvents whose boiling point is 100 degreeC or more.   The said resist base composition contains the crosslinking agent, The manufacturing method of the mask blank in any one of Claims 1-4 whose crosslinking start temperature is lower than the at least 1 sort (s) of boiling point of the said organic solvent.   The said resist base composition contains the crosslinking catalyst, and contains the said crosslinking catalyst 0.05 mass% or more and 10 mass% or less with respect to 100 mass% of said base polymers. The manufacturing method of the mask blank of description.   The manufacturing method of the mask for transfer which forms a transfer pattern in the said thin film of the mask blank manufactured by the method in any one of Claims 1-6.