JP6307269B2 - Laminate for forming fine pattern and method for producing mold - Google Patents

Description

  The present invention relates to a laminate used for forming a fine pattern, for example, a laminate having a resist layer containing a heat-reactive resist.

  In recent years, with increasing demands for higher density and higher integration in the fields of semiconductors, optical / magnetic recording, etc., a fine pattern processing technique of several hundred nm to several tens of nm or less is essential. Therefore, in order to realize such fine pattern processing, elemental technologies of each process such as a mask / stepper, exposure, resist material and the like are actively studied.

  For example, in the mask / stepper process, a special mask called a phase shift mask is used to provide a phase difference to the light and improve the precision of fine pattern processing by the effect of interference, or between the stepper lens and the wafer. An immersion technique that enables fine pattern processing by filling a liquid and largely refracting light that has passed through a lens has been studied. However, it is very difficult to reduce the manufacturing cost because the former requires an enormous cost for mask development and the latter requires an expensive apparatus.

  On the other hand, many studies have been made on resist materials. At present, the most common resist material is a photoreactive organic resist (hereinafter also referred to as “photoresist”) that reacts with an exposure light source such as ultraviolet light, electron beam, and X-ray (Patent Document 1, Non-Patent Document). Reference 1).

In the laser light used for exposure, the intensity of the laser light normally focused by a lens shows a Gaussian distribution shape as shown in FIG. At this time, the spot diameter is defined as 1 / e ² . In general, a photoresist reaction is initiated by absorbing energy represented by E = hν (E: energy, h: Planck constant, ν: wavelength). Therefore, the reaction does not strongly depend on the intensity of light, but rather depends on the wavelength of the light, so that almost all reaction occurs in the portion irradiated with light (exposed portion). For this reason, when a photoresist is used, exposure is performed faithfully to the spot diameter.

  Although a method using a photoreactive organic resist is a very effective method for forming a fine pattern of about several hundreds of nanometers, a finer pattern is formed because a photoreactive photoresist is used. It is necessary to expose with a spot smaller than the pattern required in principle. Therefore, a KrF or ArF laser having a short wavelength must be used as the exposure light source. However, since these light source devices are very large and expensive, they are not suitable from the viewpoint of manufacturing cost reduction. Further, when using an exposure light source such as an electron beam or an X-ray, the exposure atmosphere needs to be in a vacuum state. Therefore, it is necessary to use a vacuum chamber, and there are considerable limitations from the viewpoint of cost and enlargement.

  On the other hand, when an object is irradiated with laser light having the distribution shown in FIG. 1, the temperature of the object also shows the same Gaussian distribution as the intensity distribution of the laser light (see FIG. 2). At this time, if a heat-reactive resist material that is a resist that reacts (thermally deteriorates) at a certain temperature or more is used, the reaction proceeds only at a portion that exceeds a predetermined temperature as shown in FIG. The range can be exposed. That is, since it becomes possible to form a pattern finer than the spot diameter without shortening the exposure light source wavelength, the influence of the exposure light source wavelength can be reduced by using the heat-reactive resist material. .

  In the optical recording field, WOx, MoOx, and other chalcogenide glasses (Ag-As-S series) are used as thermal-reactive resist materials (optical recording materials), and they are exposed with a semiconductor laser or a 476 nm laser to form a fine pattern. The technique which performs is proposed (refer patent document 2, nonpatent literature 2). An optical disk used in the field of optical recording is a general term for media that reads information recorded on fine irregularities provided on the disk surface by irradiating a laser on a disk coated with a heat-reactive resist material. In the optical disc, the recording density is improved as the recording unit interval called the track pitch is narrowed, and the data capacity that can be recorded for each area increases. For this reason, in order to improve the recording density, research on processing technology for fine concavo-convex patterns using a resist material has been conducted.

  To date, proposals have been made to prevent diffusion of the resist by providing a diffusion prevention layer in the upper and lower layers of the resist layer in the optical recording field (see Patent Document 3). There are proposals to improve the resist characteristics by providing a layer (see Patent Document 4 and Patent Document 5), proposals to improve the resist characteristics by providing a heat dissipation layer above the resist layer, and the like.

JP 2007-144959 A Japanese Patent Laying-Open No. 2005-203552 Japanese Patent Laid-Open No. 11-115315 JP 2007-35232 A JP 2008-47251 A JP 2012-88429 A

Published by Information Organization Co., Ltd. “Latest Resist Materials” 59-P. 76 SPIE Vol. 3424 (1998) p. 20

  Patent Document 3 discloses that layers are provided above and below an optical recording material layer from the viewpoint of preventing diffusion of the optical recording material by heating. On the other hand, Patent Document 4, Patent Document 5, and Patent Document 6 improve the resist characteristics by providing a heat insulating layer, a heat radiating layer, and a crystallization suppressing layer in either the lower layer or the upper layer of the thermal reaction type resist material layer. It is disclosed. However, in these configurations, there is a limit to the formation of a uniform pattern shape.

  The present invention has been made in view of such a point, and a fine pattern forming laminate capable of processing a fine uneven pattern while realizing formation of a uniform pattern shape (pattern width and line shape is uniform), It aims at providing the manufacturing method of a mold, and a mold.

Fine patterned laminate of the present invention, viewed contains a thermal reaction type resist material used in the mask, and a thermal reaction type resist layer in which the heat reaction type resist material reacts with heat generated by light absorption, the thermal reaction And a pair of light transmissive heat conductive layers respectively provided on both main surfaces of the mold resist layer and having the same thermal conductivity.

  In the laminate for forming a fine pattern according to the present invention, it is preferable that the thermal reaction type resist material and the material constituting the thermal conductive layer are made of an inorganic material.

In a fine pattern forming laminated sheet according to the present invention, the material constituting the heat conducting layer of said pair of light transmission type are preferably the same in thermally conductive layer of the pair of light transmission type.

In the laminate for forming a fine pattern according to the present invention, it is preferable that the density of the material constituting the pair of light transmissive heat conductive layers is the same.

In the laminate for forming a fine pattern according to the present invention, the material constituting the pair of light-transmissive heat conductive layers may have an extinction coefficient of 0.2 or less at the exposure wavelength of the heat-reactive resist layer. preferable.

In the laminate for forming a fine pattern according to the present invention, the material constituting the pair of light transmission type heat conductive layers is a metal oxide, nitride, or oxynitride having a main fluoride boiling point of 250 ° C. or less. Is preferably the main component.

In the laminate for forming a fine pattern according to the present invention, the heat-reactive resist material and the material constituting the pair of light-transmissive heat conductive layers are mutually connected at a pattern formation temperature when patterning the heat-reactive resist layer. It is preferable not to react.

In the fine pattern-forming laminate of the present invention, the material constituting the pair of light transmission type heat conductive layers is an oxide, nitride, or oxynitride compound of silicon, tantalum, or a mixture thereof. A material having a main component is preferable.

In a fine pattern forming laminated sheet according to the present invention, one of the thermally conductive layer of the pair of light transmissive thermally conductive layer is composed of SiO _2, it is preferred other hand the heat conductive layer is a quartz substrate.

  In the laminate for forming a fine pattern of the present invention, the thermal reaction type resist material may be a material mainly composed of copper oxide, chromium oxide, tin oxide, cobalt oxide, or manganese oxide. preferable.

The method of mold manufacture the present invention has, on a substrate, via a first heat conductive layer of the light transmission type, viewed it contains a thermal reaction type resist material used in the mask, and the thermal reaction type resist material by light absorption A step of obtaining a laminate by sequentially forming a heat-reactive resist layer containing a heat-reactive resist material that reacts with the generated heat and a light-transmissive second heat-conductive layer having the same thermal conductivity as the first heat-conductive layer Exposing the thermal reaction type resist layer; removing the second thermal conductive layer; developing the thermal reaction type resist layer to form a mask; and (1) A step of etching the thermal conductive layer and a step of removing the thermal reaction type resist layer to obtain a mold.

  In the mold manufacturing method of the present invention, it is preferable that the heat-reactive resist material and the material constituting the heat conductive layer are formed of an inorganic material.

  In the mold manufacturing method of the present invention, it is preferable to provide the thermal reaction type resist layer, the first thermal conductive layer, and / or the second thermal conductive layer by a sputtering method, a vapor deposition method or a CVD method.

The mold manufacturing method of the present invention includes a heat-reactive resist material used for a mask on a substrate that also serves as a light-transmissive first heat conductive layer, and the heat-reactive resist material is generated by heat generated by light absorption. A step of sequentially forming a heat-reactive resist layer containing a heat-reactive resist material that reacts and a light-transmissive second heat-conductive layer having the same thermal conductivity as the first heat-conductive layer to obtain a laminate; A step of exposing the heat-reactive resist layer; a step of removing the second heat conductive layer; a step of developing the heat-reactive resist layer to form a mask; and the first heat transfer through the mask. A step of etching the layer, and a step of removing the heat-reactive resist layer to obtain a mold.
In the mold manufacturing method of the present invention, it is preferable that the heat-reactive resist material and the material constituting the second heat conductive layer are formed of an inorganic material.
In the process for producing a mold of the present invention, it is preferable that the board has a plate shape or a sleeve shape.

  In the mold manufacturing method of the present invention, it is preferable to expose the heat-reactive resist layer with a semiconductor laser.

  According to the present invention, it is possible to process a fine concavo-convex pattern while realizing formation of a uniform pattern shape (pattern width and line shape is uniform).

It is the figure which showed intensity distribution of the laser beam. It is the figure which showed the temperature distribution of the part irradiated with the laser beam. It is a cross-sectional schematic diagram of the laminated body for fine pattern formation which concerns on embodiment of this invention. It is the figure which showed the heat distribution of the resist layer irradiated with the laser beam. It is the figure which showed an example of the manufacturing method of the mold which concerns on embodiment of this invention. It is the figure which showed an example of the manufacturing method of the mold which concerns on embodiment of this invention.

  Hereinafter, an embodiment of the present invention (hereinafter abbreviated as “embodiment”) will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

  In the field of optical recording in which a heat-reactive resist material is used, research on processing technology of a fine concavo-convex pattern on a heat-reactive resist material is being conducted in order to further improve the recording density. In the heat-reactive resist material, some thermal alteration occurs in the exposed portion where the temperature has risen due to exposure, and a thermally altered exposed portion and an unmodified unexposed portion are formed. For this reason, through the development process (in the case of an ablation type in which the heat-reactive resist evaporates and sublimates by exposure, the development process is unnecessary), depending on the exposure pattern below the wavelength of the laser beam used for the exposure. It is possible to form a fine uneven pattern.

  However, in the formation of fine uneven patterns using the above-mentioned heat-reactive resist material, if the layers present on both main surfaces of the heat-reactive resist layer are composed of different materials (including air), for each material Due to the difference in thermal conductivity, heat distribution occurs in the heat-reactive resist layer during exposure. Due to this non-uniform distribution of heat, the pattern shape may become non-uniform.

  The present inventors pay attention to the fact that the thermal interference in the heat-reactive resist layer occurs through the layers and bases present on both main surfaces of the heat-reactive resist layer containing the heat-reactive resist material, Researched earnestly. As a result, the present inventors provide a layer having the same thermal conductivity (hereinafter, also simply referred to as “thermal conductive layer”) on both principal surface sides of the thermal reaction type resist layer containing the thermal reaction type resist material. Thus, the present inventors have found that a uniform pattern can be formed by making the heat distribution in the heat-reactive resist layer uniform through this heat conductive layer, and the present invention has been completed.

  The essence of the present invention is a heat-reactive resist layer containing a heat-reactive resist material used for a mask, and a pair of heat resistors that are respectively provided on both main surfaces of the heat-reactive resist layer and have the same thermal conductivity. A mold having a fine concavo-convex pattern having a uniform pattern shape (pattern width and line shape is uniform) is obtained by using a laminate for forming a fine pattern in which a laminate having a conductive layer is provided on a substrate. It is. At this time, it is preferable that the material constituting the heat-reactive resist material and the heat conductive layer is an inorganic material.

FIG. 3 is a schematic cross-sectional view of the laminate for forming a fine pattern according to the embodiment of the present invention.
As shown in FIG. 3, the laminate 1 for forming a fine pattern is provided with a base material 11, a first heat conductive layer 12 provided on the base material 11, and a first heat conductive layer 12. A thermal reaction type resist layer 13 containing a reactive type resist material and at least a second thermal conductive layer 14 provided on the thermal reaction type resist layer 13 are provided. The fine pattern-forming laminate 1 shown in FIG. 3 is based on a laminate having a pair of heat conductive layers 12 and 14 that are provided on both main surfaces of the heat-reactive resist layer 13 and have the same thermal conductivity. It is provided on the material 11. 3 shows the fine pattern forming laminate 1 in which the first heat conductive layer 12, the heat-reactive resist layer 13, and the second heat conductive layer 14 are sequentially provided on the substrate 11. In the present invention, the substrate 11 serves also as the first heat conductive layer 12, and a fine pattern forming laminate in which the heat-reactive resist layer 13 and the second heat conductive layer 14 are sequentially provided directly on the substrate 11. It is good as a body.

  In the laminate for forming a fine pattern of the present invention, the first heat conductive layer 12 and the second heat conductive layer 14 control the heat conduction in the heat-reactive resist layer 13 when the heat-reactive resist layer 13 is exposed. . As described above, the heat-reactive resist layer 13 is formed with an exposed portion that has been thermally altered by exposure and an unexposed portion that has not been altered, and a pattern corresponding to the exposure pattern is formed through a development process. A structure in which the first heat conductive layer 12 and the second heat conductive layer 14 are not provided on both principal surfaces of the heat-reactive resist layer 13, that is, a structure in which a heat-reactive resist layer is directly provided on a substrate (heat reaction In the structure in which one main surface of the mold resist layer is in contact with the base material and the other main surface is in contact with air), the difference in thermal conductivity between the base material and air is caused by exposure of the heat-reactive resist layer during exposure. Accordingly, a non-uniform temperature distribution occurs in the heat-reactive resist layer. For this reason, due to this non-uniform temperature distribution, the pattern shape of the exposed portion becomes non-uniform, and it may be difficult to make the pattern shape uniform.

  On the other hand, in the laminate 1 for forming a fine pattern according to the present invention, a pair of thermal conductive layers 12 and 14 having the same thermal conductivity are provided on both main surfaces of the thermal reaction type resist layer 13, respectively. Therefore, it is possible to control the heat conduction in the heat-reactive resist layer 13 when the heat-reactive resist layer 13 is exposed. Here, controlling the heat conduction in the heat-reactive resist layer 13 means that the heat-reactive resist layer 13 has a uniform temperature distribution when the heat-reactive resist layer 13 is exposed. With this uniform temperature distribution, the pattern shape of the exposed portion becomes uniform, and a uniform pattern shape can be formed.

  Here, when a glass substrate is used as the base material 11, the thermal conductivity of the glass substrate is about 1.38 W / m · K (300 K) in the configuration in which the heat-reactive resist layer is formed on the glass substrate. Since the thermal conductivity of air is 0.02 W / m · K (300 K), as shown in FIG. 4A, in the film thickness direction in the thermal reaction type resist layer, the interface with the air layer and the interface with the glass substrate. Thus, heat distributions with different temperatures (T1 ≠ T2) are generated. On the other hand, as shown in FIG. 3, by providing the first thermal conductive layer 12 and the second thermal conductive layer 14 having the same thermal conductivity on both main surfaces of the thermal reaction type resist layer 13, the thermal reaction type resist layer is provided. Since uniform heat conduction (heating and heat dissipation) occurs with respect to 13, a uniform heat distribution can be obtained in the film thickness direction in the heat-reactive resist layer as shown in FIG. 4B. As shown in FIG. 4B, the heat distribution is substantially the same temperature (T3) at the interface with the first heat conductive layer 12 and the interface with the second heat conductive layer 14. “Uniform heat distribution” means that the heat distribution has a Gaussian distribution shape. In addition, as shown in FIG. 4B, the heat reaction type resist layer gradually increases in thickness toward the center. A Gaussian distribution shape that increases the temperature is preferable.

  In order to make the thermal conductivity of the first heat conductive layer 12 and the second heat conductive layer 14 the same, for example, the materials constituting the respective heat conductive layers 12 and 14 are made the same, and the respective heat conductive layers It is preferable to make the density of the material which comprises 12 and 14 the same.

  It goes without saying that the thermal conductivity is the same by making the materials constituting the first thermal conductive layer 12 and the second thermal conductive layer 14 the same, but it is also preferable to make the densities the same. When the density of the material in the film forming the first thermal conductive layer 12 and the second thermal conductive layer 14 is high, that is, when there are many material components per unit volume, the thermal conductivity of the material itself (bulk) Get closer. On the other hand, when the density of the material is low, that is, when there are few material components per unit volume, the material component itself (bulk) moves away from the thermal conductivity. Therefore, when the densities of the materials constituting the first heat conductive layer 12 and the second heat conductive layer 14 are different, layers having different thermal conductivities are formed in the first heat conductive layer 12 and the second heat conductive layer 14. It will be. From the above, in order to make the thermal conductivity of the first heat conductive layer 12 and the second heat conductive layer 14 the same, the density of the material constituting each of the heat conductive layers 12 and 14 should be the same. preferable.

  Note that the material density is the same when the density of the film constituting the first heat conductive layer 12 and the second heat conductive layer 14 is measured using a spectroscopic ellipsometry method, an X-ray reflectivity method, or the like. The difference in density between the films constituting the first heat conductive layer 12 and the second heat conductive layer 14 is within ± 20%, preferably within ± 10%, more preferably within ± 5%. Most preferably, it is within ± 3%. The smaller the density difference between the films constituting the first heat conductive layer 12 and the second heat conductive layer 14, the smaller the difference in thermal conductivity, which is preferable in forming a uniform pattern.

  Further, when the difference in thermal conductivity between the first thermal conductive layer 12 and the second thermal conductive layer 14 is within ± 20%, more preferably within ± 10%, most preferably within ± 5%. Is defined that the thermal conductivity of the first thermal conductive layer 12 and the second thermal conductive layer 14 is the same. The difference in thermal conductivity is [(thermal conductivity of the first thermal conductive layer 12−thermal conductivity of the second thermal conductive layer) / average thermal conductivity of the first thermal conductive layer 12 and the second thermal conductive layer 14. Value] × 100 (%).

  In addition, the present inventors set the light transmittance of the first heat conductive layer 12 and the second heat conductive layer 14 to a predetermined extinction coefficient, so that the first main surface of the heat-reactive resist layer 13 is first. Even when the heat conductive layer 12 and the second heat conductive layer 14 are provided, the exposure characteristics of the heat-reactive resist layer 13 are not impaired, and the heat of the first heat conductive layer 12 and the second heat conductive layer 14 is reduced. It has been found that a uniform pattern shape can be formed with a uniform heat distribution according to the conductivity.

  In the laminate for forming a fine pattern of the present invention, the first heat conductive layer 12, the heat-reactive resist layer 13, and the second heat conductive layer 14 are preferably made of an inorganic material. Thereby, even if patterning formation temperature is given, it is easy to suppress reaction of the 1st heat conductive layer 12 and the thermal reaction type resist layer 13, and the 2nd heat conductive layer 14 and the heat reaction type resist layer 13, and a uniform pattern The shape can be formed. Further, the first heat conductive layer 12, the heat-reactive resist layer 13, and the second heat conductive layer 14 can all be formed by a sputtering method or the like, and have excellent film thickness accuracy, and therefore have a uniform heat distribution and a uniform pattern shape. Formation is possible.

  Further, in the laminate for forming a fine pattern of the present invention, the first heat conductive layer 12 and the second heat conductive layer 14 efficiently transfer heat from exposure to the heat-reactive resist material of the heat-reactive resist layer 13. The material used for the first heat conductive layer 12 and the second heat conductive layer 14 is preferably a material that absorbs light by exposure as much as possible and does not generate heat by exposure, that is, a light transmissive material. For this reason, as the 1st heat conductive layer 12 and the 2nd heat conductive layer 14, it is desirable that there is little coloring in an exposure wavelength, or it is transparent. As described above, by using a light transmission type material that absorbs less light as the material constituting the first heat conductive layer 12 and the second heat conductive layer 14, the first heat conductive layer 12 and the second heat conductive layer 12 at the time of exposure are used. Heat generation of the first heat conductive layer 12 and the second heat conductive layer 14 due to light absorption of the heat conductive layer 14 can be reduced, and the heat-reactive resist layer 13 can effectively absorb heat.

  In addition, as a result of intensive studies, the present inventors set the extinction coefficient of the material constituting the first heat conductive layer 12 and the second heat conductive layer 14 at the exposure wavelength to 0.2 or less, It has been found that a uniform pattern shape can be realized. For this reason, in the laminate for forming a fine pattern of the present invention, the material constituting the first thermal conductive layer 12 and the second thermal conductive layer 14 has an extinction coefficient of 0.2 at the exposure wavelength of the thermal reaction type resist layer 13. The extinction coefficient is preferably 0.15 or less, more preferably 0.15 or less, and most preferably the extinction coefficient is 0.1 or less.

  In addition, as a material constituting the first heat conductive layer 12 and the second heat conductive layer 14, the present inventors have used oxides, nitrides, or oxynitrides made of a metal having a boiling point of main fluoride of 250 ° C. or less. It has been found that the main component is preferably.

  In the laminate for forming a fine pattern of the present invention, the first heat conductive layer 12 is patterned by etching using a heat-reactive resist layer partially opened through exposure and development processes as a mask, and the mask pattern is transferred. . For this reason, it is preferable that the material which comprises the 1st heat conductive layer 12 and the 2nd heat conductive layer 14, especially the material which comprises the 1st heat conductive layer 12 is easy to dry-etch. At that time, the dry etching resistance of the material in the dry etching process is an important material selection index. In the international application number PCT / JP2009 / 067737 (international publication number WO2010 / 044400A1), the present inventors disclose the relationship between the boiling point of fluoride and the resistance to dry etching using a fluorocarbon gas. According to the present inventors, if the boiling point of fluoride is low, dry etching resistance using chlorofluorocarbon gas is low, so that dry etching is easy. From the above, the material constituting the first heat conductive layer 12 and the second heat conductive layer 14 constituting the laminate for forming a fine pattern of the present invention is an oxidation made of a metal having a boiling point of main fluoride of 250 ° C. or less. It is preferable that the main component is an oxide, nitride, or oxynitride.

In addition, the boiling point of fluoride means the boiling point (= the boiling point of the main fluoride) of the fluoride of the main valence of the metal when the element forms a polyvalent fluoride. For example, when tungsten is taken as an example, tungsten can have a valence of 2, 4, 5, or 6. For this reason, WF ₂ , WF ₄ , WF ₅ , and WF ₆ can be formed as the fluoride of tungsten. However, since the main valence of tungsten is 6, the main fluoride of tungsten is WF _6. the points, the boiling point of the primary fluoride refers to a boiling point of WF _6.

  Specifically, metals having a boiling point of 250 ° C. or less of main fluorides are boron, carbon, nitrogen, silicon, phosphorus, sulfur, vanadium, germanium, selenium, niobium, molybdenum, tellurium, tantalum, tungsten, rhenium, iridium, Platinum etc. are mentioned. Among these, the main material constituting the first heat conductive layer 12 and the second heat conductive layer 14 is an oxidation of a metal selected from the group consisting of silicon, vanadium, germanium, niobium, molybdenum, tellurium, tantalum, and tungsten. Preferred is a material mainly composed of oxide, nitride, or oxynitride, more preferably a material mainly composed of oxide, nitride, or oxynitride of a metal selected from the group consisting of silicon, niobium, tellurium, and tantalum. Most preferably, the main component is an oxide, nitride or oxynitride compound of silicon, tantalum or a mixture thereof from the viewpoint of the boiling point of the main fluoride and the reaction with the heat-reactive resist material. Material. Of the oxides, nitrides, and oxynitrides, oxides are most preferable from the viewpoints of manufacturing, reaction with the heat-reactive resist material, and heat stability. From the above, oxides of silicon, tantalum, or a mixture thereof are most preferable. Further, as will be described later, in a configuration in which the base material also serves as the first heat conductive layer, silicon oxide is most preferable as a material constituting the first heat conductive layer 12 and the second heat conductive layer 14.

  In the fine pattern forming laminate 1 according to the present invention, the heat-reactive resist layer 13 is interposed via the first heat conductive layer 12 and the second heat conductive layer 14 provided on both main surfaces of the heat-reactive resist layer 13. Are exposed. The heat-reactive resist material constituting the heat-reactive resist layer 13 is a material that induces thermal alteration by being heated by exposure and increasing in temperature. In order for the heat-reactive resist material of the heat-reactive resist layer 13 to form a uniform pattern, the material constituting the first heat conductive layer 12 and the second heat conductive layer 14 is a heat-reactive resist material as much as possible. It is preferable that the material does not react with the heat-reactive resist material at the temperature at which it is thermally altered (pattern formation temperature when the heat-reactive resist layer is patterned). The material that does not react with the heat-reactive resist material at the pattern formation temperature when patterning the heat-reactive resist layer can be selected with reference to, for example, a phase diagram.

  In the laminate 1 for forming a fine pattern of the present invention, the base material 11 may also serve as the first heat conductive layer 12. In this case, it is preferable that the base material (first heat conduction layer) is a quartz substrate and the material constituting the second heat conduction layer 14 is silicon oxide. In the laminate for forming a fine pattern of the present invention, the first thermal conductive layer 12 and the second thermal conductive layer 14 on both main surfaces of the thermal reaction type resist layer have the same thermal conductivity, so that the thermal reaction type by exposure. The resist layer 13 has a uniform heat distribution in the film thickness direction and can form a uniform fine pattern. In this case, when the material constituting the second heat conductive layer 14 is the same as the material used for the base material 11, the base material 11 can also serve as the first heat conductive layer 12. At this time, there is no particular limitation as long as it is a material that can be obtained as the base material 11 in the range of the above-described materials, but the base material 11 and the second base material are not limited in terms of availability, stability, and dry etching resistance. The material used for the heat conductive layer 14 is preferably composed mainly of silicon oxide, and among the silicon oxides, the material used for the substrate 11 is particularly preferably quartz.

  Next, the thermal reaction type resist layer of the laminate for forming a fine pattern of the present invention will be described. The heat-reactive resist material constituting the heat-reactive resist layer is not particularly limited and can be selected from the viewpoint of reactivity with the materials constituting the first heat conductive layer 12 and the second heat conductive layer 14. . For example, the following heat-reactive resist materials can be mentioned.

  In the present invention, the heat-reactive resist material includes incomplete oxides, decomposable oxides, decomposable nitrides, decomposable carbides, decomposable carbonates, decomposable sulfides, decomposable selenides, and meltable composite metals. It is preferable to contain any of a material, a phase change composite metal material, and an oxidizable composite metal material.

  The incomplete oxide is preferably an incomplete oxide of an element selected from the group consisting of transition metals and Group XII to XV elements. Incomplete oxides include Ti, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Rh, Ag, Hf, Ta, Au, Al, Zn, Ga, In, Sn, Sb, and Pb. And an incomplete oxide of an element selected from the group consisting of Bi, and Bi, and from the group consisting of Ti, Cr, Mn, Co, Cu, Nb, Ag, Ta, Au, Sn, Pb, and Bi More preferably, it is an incomplete oxide of the selected element.

Decomposable oxides include CuO, Co ₃ O ₄ , MnO ₂ , Mn ₂ O ₃ , CrO ₃ , Cr ₅ O ₁₂ , PbO ₂ , Pb ₃ O ₄ , TaO ₂ , Rh ₂ O ₃ , RuO ₂ , MgO. ₂ , CaO ₂ , BaO ₂ , or ZnO ₂ is preferable. As the decomposable _{oxide, CuO, Co 3 O 4,} MnO 2, Mn 2 O 3, CrO 3, Cr 5 O 12, PbO 2, Pb 3 O 4, MgO 2, CaO 2, BaO 2, ZnO ₂ is more preferable. Further, the decomposable oxide is more preferably CuO, Co ₃ O ₄ , MnO ₂ , Mn ₂ O ₃ , CrO ₃ , Pb ₃ O ₄ , BaO ₂ , or CaO.

The decomposable nitride is preferably any one of Zn ₃ N ₂ , CrN, Cu ₃ N, Fe ₂ N, and Mg ₃ N ₂ . Further, the decomposable carbide is more preferably NdC ₂ or Al ₄ C ₃ .

The degradable _{carbonate, MgCO 3, CaCO 3, SrCO} 3, BaCO 3, ZnCO 3, CdCO 3, Ag 2 CO 3, PbCO 3, NiCO 3, is preferably any one of. The decomposable carbonate is more preferably any of MgCO ₃ , CaCO ₃ , SrCO ₃ , and BaCO ₃ .

Decomposable sulfides include CuS, Ni ₃ S ₄ , FeS, FeS ₂ , Fe ₂ S ₃ , SnS ₂ , HfS ₂ , TiS ₂ , Rh ₂ S ₃ , RuS ₂ , Bi ₂ S ₃ , Cr ₂ S _3. , GaS, BaS ₃ , MnS ₂ , or Nd ₂ S ₃ . The decomposable sulfide is more preferably CuS, FeS ₂ , SnS ₂ , or HfS ₂ , and more preferably any of FeS ₂ or SnS ₂ .

The decomposable selenide is preferably CuSe, Bi ₂ Se ₃ , FeSe, or GaSe. The decomposable selenide is more preferably CuSe.

  Examples of meltable composite metal materials, phase change composite metal materials, and oxidizable composite metal materials include Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, Nb, Ta, Cr, Mn, Fe, Metal group (α) composed of Co, Ni, Cu, Ag, Zn, Al, Ga, In, Sn, Pb, Sb, and Bi and metal group composed of V, Mo, W, Ge, Se, and Te (β It is preferable that two kinds of metals selected from the group consisting of) are contained, and at least one of the metals is selected from the metal group (α).

  Further, as the meltable composite metal material, the phase change composite metal material, and the oxidizing composite metal material, Mg, Ti, Zr, Nb, Ta, Cr, Mn, Fe, Co, Ni, Cu, Ag, Zn, Contains two metals selected from the group consisting of a metal group (γ) consisting of Al, Ga, In, Pb, Sb and Bi and a group consisting of a metal group (δ) consisting of V, Mo, W, Ge and Te In addition, it is more preferable that at least one of the metals is selected from the metal group (γ).

  Further, as a meltable composite metal material, a phase change composite metal material, and an oxidizable composite metal material, In—Sb, Sn—Sb, Cr—Sb, Ga—Sb, In—Sn, Ni—Sn, Al— Sn, Bi-Sn, Sn-Pb, Ni-Bi, Zn-Sb, Ni-Cr, Ni-Nb, Al-Ni, Cu-Zr, Ag-Zn, Ge-Sb, Sb-Te, Bi-Te, It is more preferable to contain any one of combinations of metal species represented by Ni—W, Zn—Te, Pb—Te, Mo—Nb, W—Nb, Cr—Mo, and Cu—V.

In addition, as the meltable composite metal material, the phase change composite metal material, and the oxidizable composite metal material, In ₅ Sb _95, In ₃₂ Sb ₆₈ , In ₆₈ Sb ₃₂ , In ₁ Sb ₉₉ , Sn ₅₀ Sb ₅₀ , Cr _{50 Sb 50, Ga 50 Sb 50} , Ga 40 Sb 60, Ga 30 Sb 70, Ga 20 Sb 80, Ga 12 Sb 88, Ga 10 Sb 90, In 47 Sn 53, In 53 Sn 47, Ni 80.7 Sn 19 _.3 , Al _2.2 Sn _97.8 , Bi ₄₃ Sn ₅₇ , Sn ₂₆ Pb ₇₄ , Sn ₂₅ Pb ₇₅ , Sn ₇₄ Pb ₂₆ , Ni ₅₀ Bi ₅₀ , Ni ₄₀ Bi ₆₀ , Ni ₆₀ Bi ₄₀ , Ni ₇₀ Bi _{30, Ni 80 Bi 20, Ni} 90 Bi 10, Zn 32 Sb 68, Ni 50 Cr 50, _{i 83.8 Nb 16.2, Ni 59.8 Nb} 40.2, Al 97.3 Ni 2.7, Cu 90.6 Zr 9.4, Ag 70 Zn 30, Ge 10 Sb 90, Ge 20 Sb 80 _{, Ge 30 Sb 70, Ge 50} Sb 50, Bi 90 Te 10, Bi 97 Te 3, Ni 81 W 19, Zn 50 Te 50, Pb 50 Te 50, Mo 40 Nb 60, Mo 50 Nb 50, W 40 Nb 60 , W ₅₀ Nb ₅₀ , Cr ₈₅ Mo ₁₅ , Sb ₄₀ Te ₆₀ , Bi ₁₀ Te ₉₀ , Cu _8.6 V _91.4 , Cu _13.6 V _86.4 , Cu _18.6 V _81.4 It is particularly preferable to contain Furthermore, as the fusible composite metal material, the phase change composite metal material, and the oxidizable composite metal material, Sb ₄₀ Te ₆₀ , Bi ₁₀ Te ₉₀ , Cu _8.6 V _91.4 , Cu _13.6 V _86.4 And Cu _18.6 V _81.4 is most preferable.

In the laminate for forming a fine pattern according to the present invention, the heat-reactive resist material constituting the heat-reactive resist layer includes any of incomplete oxides of Cr, Nb, Ta, Ti, Sn, and Pb, Mn ₂ O ₃ , CuO, Co ₃ O ₄ , Pb ₃ O ₄ , BaO ₂ , CaCO ₃ , FeS ₂ , SnS ₂ are preferably selected, and from the viewpoint of forming a finer pattern, copper oxide (CuO), chromium oxide (incomplete oxide of Cr), tin oxide (incomplete oxide of Sn), cobalt oxide (Co ₃ O ₄ ), manganese oxide (Mn ₂ O ₃ ) as main components It is preferable that the material is

  The film thickness of the heat-reactive resist layer 13 is preferably in the range of 5 nm to 1 μm. When the film thickness of the heat-reactive resist layer 13 is too thin, the heat-reactive resist layer 13 cannot be sufficiently absorbed by exposure, so that the temperature is not raised to a necessary temperature, and patterning by exposure cannot be performed well. If the thickness of the thermal reaction type resist layer 13 is too thick, a temperature distribution is formed in the thickness direction, and regions and states that are thermally altered in the thermal reaction type resist layer 13 are different, so that accurate patterning cannot be performed. From the above, the thickness of the thermal reaction type resist layer 13 is preferably 5 nm or more and 1 μm or less, more preferably 5 nm or more and 500 nm or less, particularly preferably 5 nm or more and 100 nm or less, and more preferably 10 nm or more. Most preferably, it is 100 nm or less.

  As the base material 11, a flat base material, a cylindrical base material (a sleeve base material, a roll base material, a drum base material), a lenticular base material, or the like can be used. By using these base materials, the shape of the base material can be used as it is as the shape of the mold. The shape of the substrate can be selected as appropriate according to the shape of the mold to be produced.

  Many molds used for optical disc masters and nanoimprints are small and have a flat plate shape, and can therefore be transferred by a simple apparatus. When transferring to a large area with a plate-shaped mold, it is necessary to produce a large mold, but it is necessary to apply a uniform pattern to the entire surface of the large mold, to apply a uniform pressing pressure to the entire mold surface during transfer, There are problems such as clean release of the mold. On the other hand, a sleeve-shaped mold can be manufactured using a sleeve base material, and a large-area pattern can be easily manufactured by transferring with the sleeve-shaped mold. Furthermore, the lens-shaped mold can be used as a mold by directly imparting an antireflection structure or the like to the lens-shaped substrate, and the lens-shaped substrate can be used as a final product as it is.

  The material of the base material is not particularly limited, but it is possible to use a metal, glass or the like that is rich in workability. Specifically, aluminum, copper, titanium, SUS, silicon, glass, quartz, or those plated with chromium can be used. A quartz substrate can be directly dry-etched, and thus is suitable for increasing the aspect ratio.

  In general, optical materials, films, and the like are required to have a fine pattern with a high aspect ratio (a value obtained by dividing the groove depth by the groove opening width), and sometimes have an aspect ratio of 10 or more. . The depth of the groove in the film thickness direction is the same as the depth of the groove in the depth direction as the thickness of the thermal reaction type resist layer 13. Therefore, in order to form a deep groove, the film of the thermal reaction type resist layer 13 is used. It is necessary to increase the thickness. However, as the film thickness of the heat-reactive resist layer 13 increases, the uniformity of heat conduction in the film thickness direction due to exposure is lost. As a result, not only in the depth direction but also in the film surface direction The processing accuracy of the pattern also decreases.

  When it is desired to form a pattern having a finer pattern shape and a deeper groove depth, a film having a thickness corresponding to the groove depth to be formed under the thermal reaction type resist layer 13, that is, an etching layer is formed in advance. In addition, after obtaining a laminate in which the thermal reaction type resist layer 13 is formed on the etching layer, first, only the thermal reaction type resist layer 13 is exposed and developed to give a pattern shape to the resist layer. A method of forming a deep groove in the underlying etching layer using the patterned thermal reaction type resist layer 13 as a mask can be considered. By using this method, it is possible to produce an aspect ratio according to need, so that development in application can be expanded.

  In the case of forming a fine pattern with a high aspect ratio, it is preferable that the first heat conductive layer 12 constituting the fine pattern forming laminate 1 according to the present invention functions as an etching layer. The etching layer is etched by dry etching using a fluorine-based gas using the heat-reactive resist layer 13 as a mask to give a desired pattern. For this reason, the etching layer preferably contains an etching material that can be easily etched by dry etching using a fluorine-based gas. As described above, the material constituting the first thermal conductive layer 12 is preferably a material that is easily dry-etched by using a metal oxide, nitride, or oxynitride having a boiling point of fluoride of 250 ° C. or less. .

  Next, a method for producing a mold using the laminate for forming a fine pattern according to the present invention will be described.

  In the mold manufacturing method of the present invention, (1) the same as the first heat conductive layer and the heat-reactive resist layer containing the heat-reactive resist material on the substrate directly or via the first heat-conductive layer. A second thermal conductive layer having thermal conductivity is sequentially formed to obtain a laminate, (2) exposing the thermal reaction type resist layer, (3) removing the second thermal conductive layer, (4) The thermal reaction type resist layer is developed to form a mask. (5) The first thermal conductive layer is etched through the mask, or the first thermal conductive layer and the base material are etched. ) A mold is obtained by removing the thermal reaction type resist layer.

  5 and 6 are diagrams showing an example of a mold manufacturing method according to the embodiment of the present invention. In the step (1) in the method for producing a mold of the present invention, the heat-reactive resist layer containing the heat-reactive resist material and the first heat-conductive layer are directly or directly via the first heat-conductive layer. A second thermal conductive layer having thermal conductivity is sequentially formed to obtain a laminate. That is, the 1st heat conductive layer 12 is formed on the base material 11 shown to FIG. 5A (FIG. 5B). Next, as shown in FIG. 5C, a thermal reaction type resist layer 13 is formed on the first heat conductive layer 12. Further, as shown in FIG. 5D, a second heat conductive layer 14 is formed on the heat-reactive resist layer 13. Thereby, a laminated body is obtained.

  In the step (1), when the base material 11 also serves as the first thermal conductive layer 12, the thermal reaction type resist layer 13 is formed directly on the base material 11, and the second type is formed on the thermal reaction type resist layer 13. 2 The heat conductive layer 14 is formed to obtain a laminate.

  The first heat conductive layer 12, the heat-reactive resist layer 13, and / or the second heat conductive layer can be formed using a sputtering method, a vapor deposition method, or a CVD method. Since these layers can be processed with fine patterns on the order of several tens of nanometers, depending on the size of the fine pattern, the film thickness distribution of the heat-reactive resist material during film formation and the surface irregularities may have a significant effect. Conceivable. Therefore, in order to reduce these effects as much as possible, film formation methods such as sputtering, vapor deposition, and CVD are more difficult than film formation methods such as coating methods and spray methods that are somewhat difficult to control film thickness uniformity. It is preferable to form a heat-reactive resist layer. Among these, the sputtering method is particularly preferable from the viewpoints of composition adjustment, film thickness uniformity, film formation rate, and the like.

  In step (2), the heat-reactive resist layer 13 is exposed. When the heat-reactive resist layer 13 is exposed, an exposed portion 13a and an unexposed portion are generated as shown in FIG. 5E.

  The heat source for exposing the heat-reactive resist material constituting the heat-reactive resist layer 13 is not particularly limited as long as it can be heated and can achieve a desired pattern shape, but a laser that can easily form a pattern is preferable. As a laser used for exposure of the heat-reactive resist layer 13, an excimer laser such as a KrF laser or an ArF laser, a semiconductor laser, an electron beam, an X-ray, or the like can be used. Excimer lasers such as KrF lasers and ArF lasers are very large and expensive, and electron beams and X-rays require the use of a vacuum chamber, so there are considerable limitations in terms of cost and size. . Therefore, it is preferable to use a semiconductor laser that can be miniaturized and is inexpensive. In general, it has been possible to form a fine pattern by shortening the wavelength of an exposure light source using an electron beam, an excimer laser, or the like, but the heat-reactive resist material for dry etching according to the present embodiment is a semiconductor. Even with a laser, it is possible to form a sufficiently fine pattern.

  In step (3), as shown in FIG. 6A, the second heat conductive layer 14 is removed. For the removal of the second heat conductive layer 14, wet etching or dry etching is used. Next, in step (4), as shown in FIG. 6B, the thermal reaction type resist layer 13 is developed to form a mask 21. Furthermore, in the step (5), as shown in FIG. 6C, the first heat conductive layer 12 and the base material 11 are etched through the mask 21. In the step (5), only the first heat conductive layer 12 may be etched. Thereafter, in step (6), as shown in FIG. 6D, the heat-reactive resist layer 13 is removed to obtain the mold 2. In the step (6), when the first heat conductive layer 12 is provided on the substrate 11, the mold 2 is obtained by removing the first heat conductive layer 12 together with the heat-reactive resist layer 13. Note that dry etching is used for the etching in the step (5).

  Removal of the second heat conductive layer 14 in step (3), development of the heat-reactive resist layer 13 in step (4), etching of the first heat conductive layer 12 and the substrate 11 in step (5), step (6) In order to remove the heat-reactive resist layer 13 and the first heat conductive layer 12, an acid solution, an alkali solution, a complexing agent, an organic solvent, or the like can be used alone or in combination in a timely manner.

  As the acid solution, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, oxalic acid, hydrofluoric acid, ammonium nitrate, or the like can be used. As the alkaline solution, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia, TMAH (tetramethylammonium hydroxide) or the like can be used. As the complexing agent, a solution of oxalic acid, ethylenediaminetetraacetic acid and its salt, glycine or the like can be used alone or as a mixed solution.

  When used for the development in step (4), a potential adjusting agent such as hydrogen peroxide or manganese peroxide may be added to the developer. Further, the developing property may be improved by adding a surfactant or the like to the developer. In the development step, development is first performed with an acid developer and then developed with an alkali developer to achieve a desired development. Alternatively, after development with an alkali developer, development with an acid developer is performed to obtain a desired development. A plurality of stages of development may be performed to achieve the above. Depending on the heat-reactive resist material selected, development may not be necessary.

As an apparatus used for dry etching in step (3) and / or step (5), there is no particular limitation as long as a fluorocarbon gas can be introduced in vacuum, plasma can be formed, and etching can be performed. For example, a commercially available dry etching apparatus, RIE apparatus, ICP apparatus or the like can be used. The gas type, time, power, etc. for performing the dry etching treatment can be appropriately determined depending on the type of the heat-reactive resist material, the type of the first heat conductive layer (etching layer), the thickness, the etching rate, and the like. In addition, as a gas used for dry etching of the base material, an etching gas used for general dry etching may be used. Examples of the etching gas include fluorine-based gases such as CF ₄ and SF ₆ , and these may be used alone or in combination with a plurality of gases. Further, a mixture in which the above-described fluorine-based gas and a gas such as O ₂ , H ₂ , Ar, N ₂ , CO, HBr, NF ₃ , HCl, HI, BBr ₃ , BCl ₃ , Cl ₂ , and SiCl ₄ are mixed. The gas is also within the range of fluorine-based gas.

  In the mold manufactured by the above-described method, the pitch of the concavo-convex structure (pitch between adjacent convex portions) has a fine pattern in the range of 1 nm to 1 μm. In addition, the pitch here does not necessarily need to be the pitch between adjacent convex parts of a concavo-convex structure, and may be the pitch between adjacent concave parts. Further, the shape of the concavo-convex structure is not particularly limited, and examples thereof include a line and space shape, a dot shape, or a long hole shape in a plan view, and these shapes may be mixed. Examples of the cross-sectional structure of the concavo-convex structure include a triangular shape, a rectangular shape, a dome shape, and a lens shape.

(Example)
Next, examples performed for clarifying the effects of the present invention will be described. In addition, this invention is not limited at all by the following examples and comparative examples.

Example 1
A SiO ₂ was sputtered on a 50 mmφ silicon substrate under the conditions of an electric power of 100 W and an Ar gas pressure of 0.1 Pa to form a first heat conductive layer having a thickness of 10 nm. Next, a heat-reactive resist layer having a thickness of 25 nm was formed on the first heat conductive layer by sputtering CuO-10% SiO ₂ under the conditions of power of 100 W and mixed gas pressure of Ar and O ₂ of 0.1 Pa. Subsequently, SiO ₂ was sputtered on the heat-reactive resist layer under the conditions of an electric power of 100 W and an Ar gas pressure of 0.1 Pa to form a second heat conductive layer having a thickness of 10 nm. In this way, a laminate was produced. The first heat conductive layer and the second heat conductive layer were separately prepared for the density measurement by separately preparing a single heat conductive layer under the above conditions and measuring the density by the X-ray reflectivity method. / Cm ³ .

Next, the heat-reactive resist layer of the laminate was exposed under the following conditions.
Semiconductor laser wavelength for exposure: 405 nm
Lens numerical aperture: 0.85
Exposure laser power: 1mW to 25mW
Feed pitch: 120 nm to 1000 nm
Various shapes and patterns can be formed by modulating the laser intensity during exposure. In this embodiment, an isolated circle (opening diameter: 150 nm) is used as the pattern in order to confirm the uniformity of the fine pattern. Formed. As a pattern shape to be formed, a continuous groove shape, an isolated elliptical shape, or the like can be selected depending on a desired application.

Next, the second heat conductive layer of the laminate was removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa. Thereafter, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening. The cross-sectional SEM measurement was performed about the pattern shape of the obtained opening. As a result, the second heat conductive layer and the heat-reactive resist layer did not react. The opening diameter on the second heat conductive layer side (upper side) of the heat-reactive resist layer was 150 nm, and the opening diameter on the first heat conductive layer side (lower side) of the heat-reactive resist layer was 150 nm. Thus, it was found from the cross-sectional SEM that a uniform opening in the thickness direction was obtained in the heat-reactive resist layer.

Next, using this opening pattern as a mask, the first thermal conductive layer is removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa, and the remaining thermal reaction type resist layer is removed. The mold was prepared by removing. When the obtained mold was observed by SEM, it was found that a uniform pattern having a uniform opening in the depth direction was obtained.

(Example 2)
A 20 nm thick first heat conductive layer was formed by sputtering Ta ₂ O ₅ on a 50 mmφ silicon substrate under the conditions of power of 100 W and Ar gas pressure of 0.1 Pa. Next, a heat-reactive resist layer having a thickness of 25 nm was formed on the first heat conductive layer by sputtering CuO-10% SiO ₂ under the conditions of power of 100 W and mixed gas pressure of Ar and O ₂ of 0.1 Pa. Next, Ta ₂ O ₅ was sputtered on the heat-reactive resist layer under the conditions of a power of 100 W and an Ar gas pressure of 0.1 Pa to form a second heat conductive layer having a thickness of 20 nm. In this way, a laminate was produced. The first heat conductive layer and the second heat conductive layer were separately prepared for the density measurement by forming a single heat conductive layer under the above conditions and measuring the density by the X-ray reflectivity method. / Cm ³ .

Next, the heat-reactive resist layer of the laminate was exposed under the same conditions as in Example 1. Next, the second heat conductive layer of the laminate was removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa. Thereafter, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening. The cross-sectional SEM measurement was performed about the pattern shape of the obtained opening. As a result, the second heat conductive layer and the heat-reactive resist layer did not react. The opening diameter on the second heat conductive layer side (upper side) of the thermal reaction type resist layer was 250 nm, and the opening diameter on the first heat conductive layer side (lower side) of the heat reaction type resist layer was 250 nm. Thus, it was found from the cross-sectional SEM that a uniform opening in the thickness direction was obtained in the heat-reactive resist layer.

Next, using this opening pattern as a mask, the first thermal conductive layer is removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa, and the remaining thermal reaction type resist layer is removed. The mold was prepared by removing. When the obtained mold was observed by SEM, it was found that a uniform pattern having a uniform opening in the depth direction was obtained.

(Example 3)
Thermal reaction type with a thickness of 25 nm by sputtering CuO-10% SiO ₂ on a sleeve-shaped quartz substrate (SiO ₂ ) of 80 mmφ × 400 mm under the conditions of power 1000 W, mixed gas pressure of Ar and O ₂ of 0.1 Pa. A resist layer was formed. Next, SiO ₂ was sputtered on the heat-reactive resist layer under the conditions of power 2500 W and Ar gas pressure 0.1 Pa to form a second heat conductive layer having a thickness of 10 nm. In this way, a laminate was produced. The second heat conductive layer was 2.3 g / cm ³ when a single heat conductive layer was separately prepared for the density measurement and the density was measured by the X-ray reflectivity method.

Next, the heat-reactive resist layer of the laminate was exposed under the following conditions.
Semiconductor laser wavelength for exposure: 405 nm
Lens numerical aperture: 0.85
Exposure laser power: 1mW to 25mW
Feed pitch: 120 nm to 350 nm
Rotation speed: 210rpm-1670rpm
Various shapes and patterns can be formed by modulating the laser intensity during exposure, but in this embodiment, an isolated circle (opening diameter: 170 nm) is used as the pattern in order to confirm the uniformity of the fine pattern. Formed.

Next, the second heat conductive layer of the laminate was removed by dry etching using SF ₆ gas under the conditions of power 1000 W and gas pressure 5 Pa. Thereafter, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening.

  A UV curable resin was applied onto the heat-reactive resist layer and UV cured to obtain a UV-cured film to which the opening pattern of the heat-reactive resist layer was transferred. This UV cured film was subjected to surface SEM and cross-sectional SEM measurements. As a result, there was no evidence of reaction between the second heat conductive layer and the heat-reactive resist layer. Further, the upper diameter of the opening in the film was 170 nm, and the lower diameter of the opening in the film was 170 nm. Thus, it was found from the cross-sectional SEM that a uniform opening in the thickness direction was obtained in the heat-reactive resist layer.

Next, using this opening pattern as a mask, the first thermal conductive layer is removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa, and the remaining thermal reaction type resist layer is removed. The mold was prepared by removing. A UV curable film to which the opening pattern of the mold was transferred was obtained by applying a UV curable resin to the obtained mold and performing UV curing. When this UV cured film was observed by SEM, it was found that a uniform pattern having a uniform opening in the depth direction was obtained.

(Comparative Example 1)
A SiO ₂ was sputtered on a 50 mmφ silicon substrate under the conditions of an electric power of 100 W and an Ar gas pressure of 0.1 Pa to form a first heat conductive layer having a thickness of 10 nm. Next, a heat-reactive resist layer having a thickness of 25 nm was formed on the first heat conductive layer by sputtering CuO-10% SiO ₂ under the conditions of power of 100 W and mixed gas pressure of Ar and O ₂ of 0.1 Pa. Next, Te was sputtered on the heat-reactive resist layer under the conditions of power 80 W and Ar gas pressure 0.1 Pa to form a second heat conductive layer having a thickness of 10 nm. In this way, a laminate was produced.

Next, the heat-reactive resist layer of the laminate was exposed under the same conditions as in Example 1. Next, the second heat conductive layer of the laminate was removed by dry etching using CF ₄ gas under the conditions of power 300 W and gas pressure 5 Pa. Thereafter, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening. The cross-sectional SEM measurement was performed about the pattern shape of the obtained opening. As a result, the second heat conductive layer and the heat-reactive resist layer did not react. The opening diameter on the second heat conductive layer side (upper side) of the heat-reactive resist layer was 140 nm, and the opening diameter on the first heat conductive layer side (lower side) of the heat-reactive resist layer was 150 nm. As described above, it was found from the cross-sectional SEM that a uniform opening in the thickness direction could not be obtained in the thermal reaction type resist layer. This is considered to be because the thermal conductivity of the layers on both main surfaces of the thermal reaction type resist layer is different, that is, the material of the first thermal conductive layer is different from the material of the second thermal conductive layer.

(Comparative Example 2)
A SiO ₂ was sputtered on a 50 mmφ silicon substrate under the conditions of an electric power of 100 W and an Ar gas pressure of 0.1 Pa to form a first heat conductive layer having a thickness of 10 nm. Next, a heat-reactive resist layer having a thickness of 25 nm was formed on the first heat conductive layer by sputtering CuO-10% SiO ₂ under the conditions of power of 100 W and mixed gas pressure of Ar and O ₂ of 0.1 Pa. In this way, a laminate was produced.

  Next, the heat-reactive resist layer of the laminate was exposed under the same conditions as in Example 1. Next, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening. The cross-sectional SEM measurement was performed about the pattern shape of the obtained opening. As a result, the opening diameter on the second heat conductive layer side (upper side) of the thermal reaction type resist layer was 165 nm, and the opening diameter on the first heat conductive layer side (lower side) of the heat reaction type resist layer was 155 nm. . As described above, it was found from the cross-sectional SEM that a uniform opening in the thickness direction could not be obtained in the heat-reactive resist layer. This is considered to be because the thermal conductivity of the layers on both main surfaces of the thermal reaction type resist layer is different, that is, the material of the first thermal conductive layer and the material (air) of the second thermal conductive layer are different.

(Comparative Example 3)
A SiO ₂ was sputtered on a 50 mmφ silicon substrate under the conditions of an electric power of 100 W and an Ar gas pressure of 0.1 Pa to form a first heat conductive layer having a thickness of 10 nm. Next, a heat-reactive resist layer having a thickness of 25 nm was formed on the first heat conductive layer by sputtering CuO-10% SiO ₂ under the conditions of power of 100 W and mixed gas pressure of Ar and O ₂ of 0.1 Pa. Next, SiO ₂ was sputtered on the heat-reactive resist layer under the conditions of an electric power of 100 W and an Ar gas pressure of 5 Pa to form a second heat conductive layer having a thickness of 10 nm. In this way, a laminate was produced. The first heat conductive layer and the second heat conductive layer were prepared by separately preparing a single heat conductive layer under the above conditions for density measurement, and measuring the respective densities by the X-ray reflectivity method. The density of the heat conductive layer was 2.3 g / cm ³ , and the density of the second heat conductive layer was 1.7 g / cm ³ .

Next, the heat-reactive resist layer of the laminate was exposed under the same conditions as in Example 1. Next, the second heat conductive layer of the laminate was removed by dry etching using SF ₆ gas under the conditions of power 300 W and gas pressure 5 Pa. Thereafter, the heat-reactive resist layer was developed with a 0.3% glycine aqueous solution to form a pattern having a circular opening. The cross-sectional SEM measurement was performed about the pattern shape of the obtained opening. As a result, the second heat conductive layer and the heat-reactive resist layer did not react. The opening diameter on the second heat conductive layer side (upper side) of the thermal reaction type resist layer was 160 nm, and the opening diameter on the first heat conductive layer side (lower side) of the heat reaction type resist layer was 150 nm. As described above, it was found from the cross-sectional SEM that a uniform opening in the thickness direction could not be obtained in the heat-reactive resist layer. This is considered to be because the thermal conductivity of the layers on both main surfaces of the thermal reaction type resist layer is different, that is, the density of the first thermal conductive layer is different from the density of the second thermal conductive layer.

(Comparative Example 4)
A laminated body was formed under the same conditions as in Example 1 except that the first heat conductive layer (lower side) and the second heat conductive layer (upper side) were changed to acrylic resin and the film thickness was changed to 30 nm. Body exposure was performed. Next, removal of the second heat conductive layer of the laminate was attempted by dry etching (O ₂ ashing) using O ₂ gas under the conditions of power 1000 W and gas pressure 5 Pa. As a result, the acrylic resin constituting the second conductive layer was fused (reacted) to the surface of the heat-reactive resist material and could not be completely removed, and a uniform fine pattern could not be obtained. This is because the acrylic resin and the heat-reactive resist layer reacted at the pattern formation temperature. Thus, it has been found that when the heat-reactive resist material is made of an inorganic material, the materials constituting the first heat conductive layer and the second heat conductive layer are also preferably inorganic materials.

  The present invention is not limited to the embodiment described above, and can be implemented with various modifications. For example, the material, arrangement, shape, and the like of the members in the above embodiment are illustrative, and can be implemented with appropriate changes. In addition, various modifications can be made without departing from the scope of the present invention.

  The present invention has an effect that a fine pattern pitch and a uniform pattern shape can be realized, and can be suitably used, for example, for forming a mold having a fine pattern.

DESCRIPTION OF SYMBOLS 1 Laminated body for fine pattern formation 2 Mold 11 Base material 12 1st heat conductive layer 13 Thermal reaction type resist layer 13a Exposure part 14 2nd heat conductive layer 21 Mask

Claims (17)

  A heat-reactive resist material used for a mask, and the heat-reactive resist material is provided on both main surfaces of the heat-reactive resist layer that reacts with heat generated by light absorption and the heat-reactive resist layer, respectively. And a pair of light transmissive heat conductive layers each having the same thermal conductivity.   The laminate for forming a fine pattern according to claim 1, wherein the material constituting the heat-reactive resist material and the heat conductive layer is made of an inorganic material.   3. The laminate for forming a fine pattern according to claim 1, wherein the material constituting the pair of light transmission type heat conduction layers is the same in the pair of light transmission type heat conduction layers. .   The laminate for forming a fine pattern according to any one of claims 1 to 3, wherein the density of the material constituting the pair of light transmission type heat conductive layers is the same.   5. The material constituting the pair of light transmission type heat conductive layers has an extinction coefficient of 0.2 or less at an exposure wavelength of the heat reaction type resist layer. The laminated body for fine pattern formation of crab.   The material constituting the pair of light-transmissive heat conductive layers is mainly composed of a metal oxide, nitride, or oxynitride whose main fluoride has a boiling point of 250 ° C or lower. The laminated body for fine pattern formation in any one of Claims 1-5.   2. The heat-reactive resist material and the material constituting the pair of light-transmissive heat conductive layers do not react with each other at a pattern formation temperature when patterning the heat-reactive resist layer. Item 7. The laminated body for forming a fine pattern according to any one of Items 6 above.   The material constituting the pair of light transmission type heat conductive layers is a material mainly composed of a compound of oxide, nitride, or oxynitride of silicon, tantalum, or a mixture thereof. The laminate for forming a fine pattern according to any one of claims 1 to 7. Said pair of one of the heat conducting layer of the light transmission type thermally conductive layer is composed of SiO _2, to one of the claims 1 to 8, wherein the other side the heat conductive layer is a quartz substrate The laminated body for fine pattern formation of description.   The thermal reaction type resist material is a material mainly composed of copper oxide, chromium oxide, tin oxide, cobalt oxide, or manganese oxide. The laminated body for fine pattern formation of crab.   A heat-reactive resist material containing a heat-reactive resist material used for a mask on a substrate via a light-transmissive first heat conductive layer, and reacting with heat generated by light absorption of the heat-reactive resist material And a step of sequentially forming a light-transmissive second heat conductive layer having the same thermal conductivity as that of the first heat conductive layer to obtain a laminate, and exposing the heat reactive resist layer A step of removing the second thermal conductive layer, a step of developing the thermal reaction type resist layer to form a mask, a step of etching the first thermal conductive layer through the mask, Removing the heat-reactive resist layer to obtain a mold.   The method for producing a mold according to claim 11, wherein the material constituting the heat-reactive resist material and the heat conductive layer is formed of an inorganic material.   A heat-reactive resist material used for a mask is included on a substrate that also serves as a light-transmissive first heat conductive layer, and the heat-reactive resist material includes a heat-reactive resist material that reacts with heat generated by light absorption. A step of sequentially forming a heat-reactive resist layer and a light-transmissive second heat-conductive layer having the same thermal conductivity as the first heat-conductive layer to obtain a laminate; and a step of exposing the heat-reactive resist layer Removing the second heat conductive layer; developing the heat-reactive resist layer to form a mask; etching the first heat conductive layer through the mask; And a step of removing the reactive resist layer to obtain a mold.   The method for manufacturing a mold according to claim 13, wherein the material constituting the heat-reactive resist material and the second heat conductive layer is formed of an inorganic material.   15. The thermal reaction type resist layer, the first thermal conductive layer, and / or the second thermal conductive layer are provided by a sputtering method, a vapor deposition method, or a CVD method. The manufacturing method of the mold of description. Method for producing a mold according to claims 11 to claim 15, characterized in that said base plate has a plate shape or a sleeve shape.   The method for producing a mold according to claim 11, wherein the heat-reactive resist layer is exposed with a semiconductor laser.

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