Method and apparatus for forming a pattern

Abstract

To provide a pattern forming method capable of forming an inverted pattern.SOLUTION: In one exemplary embodiment, a method for forming a pattern includes (a) forming, on a substrate, a first pattern having an opening and containing a first material, (b) forming a filling portion in the opening, the filling portion containing a second material different from the first material, and (c) removing the first pattern so that the filling portion remains as a second pattern inverted with respect to the first pattern. At least one of the first material and the second material contains tin.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] An exemplary embodiment of the present disclosure relates to a method for forming a pattern. [Background technology]

[0002] Patent Document 1 discloses a method for patterning a substrate. In this method, a substrate having a radiation-sensitive layer is first received. A patterned resist mask is then created on the substrate by developing a pattern transferred to the radiation-sensitive layer via an extreme ultraviolet lithography process. The patterned resist mask is then overcoated with an image-reversal material. The top of the image-reversal material is then removed. The patterned resist mask is then removed to create a patterned image-reversal material mask. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2016-539361 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a pattern formation method that can form a reverse pattern. [Means for solving the problem]

[0005] In one exemplary embodiment, a method for forming a pattern includes: (a) forming a first pattern on a substrate, the first pattern having an opening and comprising a first material; (b) forming a filler portion in the opening, the filler portion comprising a second material different from the first material; and (c) removing the first pattern, so that the filler portion remains as a second pattern that is inverted relative to the first pattern, wherein at least one of the first material and the second material comprises tin. [Effects of the Invention]

[0006] According to one exemplary embodiment, a pattern formation method is provided that is capable of forming a reverse pattern. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a flow diagram of a pattern formation method according to one exemplary embodiment. [Figure 2] 2(a) to 2(c) are cross-sectional views showing some steps of the pattern formation method according to the first embodiment. [Figure 3] 3(a) to 3(c) are cross-sectional views showing some steps of the pattern formation method according to the first embodiment. [Figure 4] 4(a) to 4(d) are cross-sectional views showing some steps of the pattern formation method according to the second embodiment. [Figure 5] 5(a) to 5(c) are cross-sectional views showing some steps of the pattern formation method according to the third embodiment. [Figure 6] 6(a) to 6(c) are cross-sectional views showing some steps of the pattern formation method according to the third embodiment. [Figure 7] 7(a) and 7(b) are cross-sectional views showing some steps of the pattern formation method according to the fourth embodiment. [Figure 8] 8(a) to 8(c) are cross-sectional views showing some steps of the pattern formation method according to the fourth embodiment. [Figure 9] FIG. 9 is a flow diagram of a pattern formation method according to one exemplary embodiment. [Figure 10] 10(a) to 10(c) are cross-sectional views showing some steps of the pattern formation method according to the fifth embodiment. [Figure 11] FIG. 11 is a flow diagram of a pattern formation method according to one exemplary embodiment. [Figure 12] 12(a) to 12(c) are cross-sectional views showing some steps of the pattern formation method according to the sixth embodiment. [Figure 13]FIG. 13 is a diagram schematically illustrating an apparatus for carrying out a pattern formation method according to one exemplary embodiment. [Figure 14] FIG. 14 is a diagram schematically illustrating an apparatus for carrying out a pattern formation method according to another exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Various exemplary embodiments are described below.

[0009] In one exemplary embodiment, a method for forming a pattern includes: (a) forming a first pattern on a substrate, the first pattern having an opening and comprising a first material; (b) forming a filler portion in the opening, the filler portion comprising a second material different from the first material; and (c) removing the first pattern, so that the filler portion remains as a second pattern that is inverted relative to the first pattern, wherein at least one of the first material and the second material comprises tin.

[0010] According to the above method, the pattern can be inverted from the first pattern to the second pattern.

[0011] The first material may include tin, in which case the pattern can be reversed from the first pattern including tin to the second pattern.

[0012] The first material may include tin oxide.

[0013] The second material may include at least one of an organic material, silicon, and a metal.

[0014] In the step (c), the first pattern may be removed using hydrogen bromide gas, in which case the first pattern can be removed without using plasma, thereby increasing the etching selectivity of the first pattern to the filling portion.

[0015] The second material may comprise tin, in which case the pattern can be reversed from the first pattern to the second pattern comprising tin.

[0016] The second material may include tin oxide.

[0017] The first material may include at least one of an organic material, silicon, and a metal.

[0018] The first material may include tin, the second material may include at least one of an organic material, silicon, and a metal, and in (c), the first pattern may be removed using at least one of hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, hydrogen iodide gas, fluorine gas, chlorine gas, bromine gas, iodine gas, boron trichloride gas, helium gas, neon gas, argon gas, xenon gas, nitrogen gas, a hydrocarbon gas, and methanol gas.

[0019] The first material may include tin oxide, and the second material may include at least one of an organic material and silicon.

[0020] In the step (c), the first pattern may be removed using at least one of hydrogen bromide gas and hydrocarbon gas.

[0021] The first material may include an organic substance, the second material may include tin, and in (c), the first pattern may be removed using at least one of an oxygen-containing gas, a fluorine-containing gas, and a nitrogen-containing gas.

[0022] The first material may include silicon, the second material may include tin, and in (c), the first pattern may be removed using a fluorine-containing gas.

[0023] The first material may include tin, the second material may include tin oxide, the second material may have a higher oxygen concentration than the first material, and (c) may remove the first pattern using at least one of hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, hydrogen iodide gas, fluorine gas, chlorine gas, bromine gas, iodine gas, boron trichloride gas, helium gas, neon gas, argon gas, xenon gas, nitrogen gas, hydrocarbon gas, and methanol gas.

[0024] The tin-containing pattern of the first pattern and the second pattern may be formed from a CVD film or an ALD film.

[0025] The CVD film or the ALD film may be a photoresist film containing tin.

[0026] The photoresist film may be a photoresist film for EUV exposure.

[0027] The unexposed portion of the photoresist film may contain tin, the exposed portion of the photoresist film may contain tin oxide, and the exposed portion may have a higher oxygen concentration than the unexposed portion.

[0028] The step (a) may include the steps of: (a1) forming a mask pattern corresponding to the first pattern on an underlayer provided on the substrate; and (a2) etching the underlayer using the mask pattern to form the first pattern. In this case, a pattern corresponding to the first pattern can be formed from the underlayer.

[0029] The underlayer may include at least one of a silicon-containing film and an organic film.

[0030] The filling portion may be a first filling portion, and the method may further include the steps of (d) forming a second filling portion in the opening of the second pattern, the second filling portion including a third material different from the first material and the second material, and (e) removing the second pattern so that the second filling portion remains as a third pattern corresponding to the first pattern. In this case, a third pattern having the same shape as the first pattern but made of a different material is obtained.

[0031] The filling portion may be a first filling portion, and the method may further include, before (a), (f) forming a third pattern on the substrate having an opening and containing a third material, the third material being different from the first material and the second material, and (g) forming a second filling portion containing the first material in the opening of the third pattern, wherein, in (a), the third pattern is removed so that the second filling portion remains as the first pattern. In this case, a second pattern having the same shape as the third pattern but made of a different material is obtained.

[0032] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0033] Fig. 1 is a flow chart of a pattern formation method according to one exemplary embodiment. The method shown in Fig. 1 (hereinafter referred to as "method MT") includes steps ST1, ST2, and ST3. Steps ST1 to ST3 can be performed in sequence. Method MT of the first embodiment to method MT of the fourth embodiment will be described below.

[0034] (First embodiment) 2(a) to 2(c) and 3(a) to 3(c) are cross-sectional views showing some steps of the pattern formation method according to the first embodiment. Hereinafter, the method MT of the first embodiment will be described with reference to FIGS.

[0035] In step ST1, as shown in FIG. 2, a pattern PT1 (first pattern) having an opening OP1 is formed on a substrate W. The pattern PT1 includes a first material. In this embodiment, the first material includes tin (Sn). The first material may include tin oxide (SnO). Examples of the first material include a tin-containing resist material. The opening OP1 is, for example, a hole. Step ST1 can be performed as follows.

[0036] First, as shown in FIG. 2(a), a photoresist film 18 is formed on a substrate W. The substrate W may include a silicon-containing film 10 and an oxide film 12. The oxide film 12 is disposed between the silicon-containing film 10 and the photoresist film 18. The oxide film 12 is, for example, a silicon oxide film. An underlayer UR may be provided on the substrate W. The underlayer UR may include a first layer 14 and a second layer 16. The first layer 14 is disposed between the oxide film 12 and the second layer 16. The first layer 14 may be, for example, an organic film such as a carbon film. The second layer 16 may be a silicon-containing film. An example of the silicon-containing film is a silicon oxide film (SiO x ), silicon nitride (SiN), silicon carbide (SiC) and silicon oxynitride (SiON).

[0037] The photoresist film 18 may be formed on the underlayer UR. The photoresist film 18 contains tin. The photoresist film 18 may be a negative resist film. The photoresist film 18 may be formed by a wet process or a dry process. An example of a wet process includes coating. The photoresist film 18 may be formed, for example, by coating a tin-containing resist material on the substrate W. An example of a dry process includes CVD. The photoresist film 18 may be formed by CVD using a tin-containing gas. Examples of the tin-containing gas include an organotin compound gas, SnCl4 gas, Sn(CH3)4 gas, and SnH4 gas.

[0038] 2(b), the photoresist film 18 is exposed to light using, for example, a photomask. The exposure forms exposed portions 18a and unexposed portions 18b in the photoresist film 18. The exposure can produce tin oxide in the exposed portions 18a. Extreme ultraviolet (EUV) or other light may be used for the exposure.

[0039] Next, as shown in FIG. 2C, the unexposed portions 18b are removed by development to form openings OP1. As a result, the exposed portions 18a remain as pattern PT1. The unexposed portions 18b can be removed by a wet process or a dry process. In the dry process, the temperature may be between −60° C. and 120° C., and the pressure may be between 0.1 mTorr (0.01333 Pa) and 760 mTorr (101.308 kPa). The unexposed portions 18b can be removed by a substance containing at least one of hydrogen and a halogen. Examples of halogen-containing substances include fluorine gas (F), chlorine gas (Cl), bromine gas (Br), iodine gas (I), and boron trichloride gas (BCl). The unexposed portions 18b can be removed by a substance containing at least one of hydrogen, chlorine, and bromine. The hydrogen-containing substance can be a hydrogen-containing gas or a hydrogen-containing liquid. Examples of hydrogen-containing gases include hydrogen (H2) gas, hydrogen chloride (HCl) gas, hydrogen bromide (HBr) gas, hydrogen fluoride (HF) gas, and hydrogen iodide (HI) gas. Examples of hydrogen-containing liquids include hydrochloric acid (HCl), hydrobromic acid (HBr), and nitric acid (HNO3). The chlorine-containing substance may be a chlorine-containing gas. Examples of chlorine-containing gases include Cl2 and BCl3. The bromine-containing substance may be a bromine-containing gas. Examples of bromine-containing gases include Br2. The unexposed portions 18b may be removed using at least one of helium gas, neon gas, argon gas, xenon gas, nitrogen gas, hydrocarbon gas, and methanol (CH3OH) gas. The unexposed portions 18b may be removed by plasma (ashing) generated from a gas containing at least one of hydrogen, chlorine, and bromine, or may be removed by a gas containing at least one of hydrogen, chlorine, and bromine without using plasma. When hydrogen bromide gas is used, the unexposed portions 18b can be removed without using plasma.

[0040] In step ST2, as shown in FIGS. 3A and 3B, a filling portion FL1 (first filling portion) is formed in the opening OP1. The filling portion FL1 includes a second material different from the first material. The second material may not include tin. The second material may include at least one of an organic material, silicon, and a metal. An example of the organic material includes spin-on carbon (SOC). The metal may be a metal other than tin. Examples of the metal include aluminum (Al), tungsten (W), titanium (Ti), hafnium (Hf), zirconium (Zr), and the like. The second material may include a silicon-containing material such as silicon oxide. Examples of the silicon-containing material include spin-on glass (SOG). When the first material includes tin, the second material may include tin oxide. The oxygen concentration of the second material may be higher than the oxygen concentration of the first material. The first material may not include oxygen. Step ST2 may be performed as follows.

[0041] 3A, a filling film FL1a to be filled in the opening OP1 is formed on the substrate W. The filling film FL1a may be formed so as to cover the pattern PT1. The filling film FL1a may be formed by a wet process or a dry process.

[0042] An example of the wet process includes coating. For example, a liquid second material is coated on the substrate W using a spin coater. The liquid second material is then solidified by exposure or baking. This allows the filling film FL1a to be formed.

[0043] An example of a dry process includes CVD. If the fill film FL1a contains, for example, silicon, the fill film FL1a can be formed by CVD using a silicon-containing gas. Examples of the silicon-containing gas include SiCl4 gas, Si2Cl6 gas, and SiBr4 gas. The silicon-containing gas vaporizes under high temperature or low pressure conditions and liquefies under low temperature or high pressure conditions. Therefore, by adjusting at least one of the temperature and pressure, a liquid second material can be formed on the substrate W. The liquid second material is then solidified by oxidation or chlorine desorption. This allows the fill film FL1a to be formed.

[0044] Next, as shown in FIG. 3(b), the upper part of the filling film FL1a is removed by, for example, etching or CMP, as needed. This forms the filling portion FL1 from the filling film FL1a. If the filling film FL1a is, for example, an organic film, the filling film FL1a can be etched by, for example, a mixed gas of nitrogen gas and hydrogen gas, or an oxygen-containing gas. Examples of the oxygen-containing gas include oxygen gas. If the filling film FL1a is, for example, a silicon-containing film, the filling film FL1a can be etched by, for example, a fluorine-containing gas. The fluorine-containing gas may contain carbon. Examples of the fluorine-containing gas include fluorocarbon (C x F y ) gas.

[0045] In step ST3, as shown in FIG. 3C, the pattern PT1 is removed, and the filling portion FL1 remains as a pattern PT2 (second pattern) that is the inverse of the pattern PT1. Using a substance containing at least one of hydrogen, chlorine, and bromine allows etching of the pattern PT1 with a high selectivity relative to the filling portion FL1. When the pattern PT1 is removed using hydrogen bromide gas, the pattern PT1 can be removed without using plasma, thereby increasing the etching selectivity of the pattern PT1 relative to the filling portion FL1.

[0046] Examples of materials for removing the pattern PT1 are the same as the examples of materials for removing the unexposed portions 18b in step ST1. The pattern PT1 can be removed using at least one of hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, hydrogen iodide gas, fluorine gas, chlorine gas, bromine gas, iodine gas, boron trichloride gas, helium gas, neon gas, argon gas, xenon gas, nitrogen gas, hydrocarbon gas, and methanol (CHOH) gas. The pattern PT1 can be removed by plasma (ashing) generated from a gas containing at least one of hydrogen, chlorine, and bromine, or by a gas containing at least one of hydrogen, chlorine, and bromine without using plasma.

[0047] After step ST3, the base film UR may be etched using the pattern PT2 as a mask. As a result, a pattern corresponding to the pattern PT2 is formed from the base film UR. Thereafter, the oxide film 12 may be etched using the obtained pattern as a mask. As a result, a pattern is formed from the oxide film 12. Thereafter, the silicon-containing film 10 may be etched using the pattern obtained from the oxide film 12 as a mask.

[0048] According to the method MT of this embodiment, the pattern PT1 can be inverted to the pattern PT2. Because a tin-containing photoresist film is typically a negative resist film, it is difficult to reduce the dimensions of a pattern formed from a tin-containing photoresist film. However, according to the method MT of this embodiment, by reducing the dimensions of the opening OP1 in the pattern PT1, a relatively small pattern PT2 can be formed. Therefore, a relatively small contact hole can be formed in the silicon-containing film 10 by etching using the pattern PT2 as a mask. Furthermore, according to the method MT of this embodiment, by using a substance containing at least one of hydrogen, chlorine, and bromine in step ST3, the tin-containing pattern PT1 can be selectively removed while leaving the filling portion FL1. Tin-containing materials have the unique property of being more reactive with substances containing at least one of hydrogen, chlorine, and bromine than many other materials. Therefore, using the tin-containing pattern PT1 broadens the range of materials for the filling portion FL1.

[0049] (Second embodiment) 4(a) to 4(d) are cross-sectional views showing some steps of the pattern formation method according to the second embodiment. Hereinafter, the method MT of the second embodiment will be described with reference to FIGS.

[0050] In this embodiment, in step ST1, as shown in Fig. 4(a), a pattern PT11 (first pattern) having an opening OP2 is formed on a substrate W. The pattern PT11 includes the same first material as the pattern PT1. Step ST1 can be performed as follows.

[0051] 2, in step ST1, first, a pattern PT1 (mask pattern) corresponding to the pattern PT11 is formed on an undercoat film UR provided on a substrate W. The pattern PT1 can be formed in the same manner as in the first embodiment.

[0052] 4(a), the base film UR is etched using the pattern PT1 as a mask to form a pattern PT11. For example, a pattern 14a and a pattern 16a are formed from the first layer 14 and the second layer 16, respectively. The pattern PT11 may include the pattern PT1, the pattern 14a, and the pattern 16a.

[0053] In step ST2, as shown in (b) and (c) of Figure 4, a filling portion FL2 is formed in the opening OP2. The filling portion FL2 includes the same second material as the filling portion FL1. Step ST2 can be performed as follows.

[0054] First, as shown in Fig. 4(b), a filling film FL2a to be filled in the opening OP2 is formed on the substrate W. The filling film FL2a may be formed so as to cover the pattern PT11. The filling film FL2a may be formed in the same manner as the filling film FL1a.

[0055] Next, as shown in Figure 4 (c), if necessary, the upper part of the filling film FL2a may be removed. This forms a filling portion FL2 from the filling film FL2a. The upper part of the filling film FL2a can be removed in the same way as the upper part of the filling film FL1a.

[0056] 4(d), by removing the pattern PT11, the filling portion FL2 remains as a pattern PT12 (second pattern) that is an inverse of the pattern PT11. The pattern PT1 in the pattern PT11 can be removed by etching similar to the etching in step ST3 of the first embodiment. The patterns 14a and 16a in the pattern PT11 are removed by etching similar to the etching of the base film UR in step ST1 of the present embodiment.

[0057] According to the method MT of this embodiment, the aspect ratio of the pattern PT12 can be made larger than that of the pattern PT2 of the first embodiment. Therefore, when etching the oxide film 12 using the pattern PT12 as a mask, a good etching selectivity can be obtained.

[0058] (Third embodiment) 5(a) to 5(c) and 6(a) to 6(c) are cross-sectional views showing some steps of the pattern formation method according to the third embodiment. Hereinafter, the method MT of the third embodiment will be described with reference to FIGS. 1, 5, and 6.

[0059] In step ST1, as shown in FIG. 5, a pattern PT21 (first pattern) having an opening OP3 is formed on the substrate W. The pattern PT21 includes a first material. In this embodiment, the first material may include at least one of an organic substance, silicon, and a metal. The first material may not include tin. The first material in this embodiment may be the same as the second material in the first embodiment. The opening OP3 is, for example, a hole. Step ST1 can be performed as follows.

[0060] First, as shown in FIG. 5(a), a photoresist film 28 is formed on a substrate W. The photoresist film 28 may be formed on an underlayer UR. The photoresist film 28 may contain at least one of an organic material, silicon, and a metal. The photoresist film 28 may be a positive resist film or a negative resist film. The photoresist film 28 may be formed by a wet process or a dry process. An example of a wet process includes coating. An example of a dry process includes CVD.

[0061] 5(b), the photoresist film 28 is exposed to light using, for example, a photomask. As a result of the exposure, exposed portions 28a and unexposed portions 28b are formed from the photoresist film 28.

[0062] Next, as shown in FIG. 5(c), the exposed portions 28a are removed by development to form openings OP3. As a result, a pattern PT21 is formed from the unexposed portions 28b. In this case, the photoresist film 28 is a positive resist film. If the photoresist film 28 is a negative resist film, the unexposed portions 28b are removed, and the pattern PT21 is formed from the exposed portions 28a.

[0063] In step ST2, as shown in (a) and (b) of FIG. 6, a filling portion FL3 (first filling portion) is formed in the opening OP3. The filling portion FL3 includes a second material different from the first material. The second material includes tin. The second material may include tin oxide. Examples of the second material include tin-containing organic materials, etc. The second material of this embodiment may be the same as the first material of the first embodiment. Step ST2 can be performed as follows.

[0064] First, as shown in FIG. 6A, a filling film FL3a to be filled in the opening OP3 is formed on the substrate W. The filling film FL3a may be formed to cover the pattern PT21. The filling film FL3a may be formed by a wet process or a dry process. Examples of wet processes include coating. Examples of dry processes include CVD. The filling film FL3a may be formed by CVD using a tin-containing gas. Examples of tin-containing gases include organotin compound gas, SnCl4 gas, Sn(CH3)4 gas, and SnH4 gas. The tin-containing gas vaporizes under high temperature or low pressure conditions and liquefies under low temperature or high pressure conditions. Therefore, by adjusting at least one of the temperature and pressure, the liquid second material can be filled in the opening OP3. Then, the liquid second material is solidified by oxidation or chlorine desorption. This allows the filling film FL3a to be formed.

[0065] 6(b), the upper portion of the filler film FL3a is removed as needed, for example, by etching or CMP. This forms the filler portion FL3 from the filler film FL3a. The filler film FL3a may be removed by plasma (ashing) generated from a gas containing at least one of hydrogen, chlorine, and bromine, or may be removed by a gas containing at least one of hydrogen, chlorine, and bromine without using plasma.

[0066] 6(c), by removing the pattern PT21, the filling portion FL3 remains as a pattern PT22 (second pattern) that is the inverse of the pattern PT21. If a substance that does not contain hydrogen, chlorine, or bromine is used, the pattern PT21 can be etched with a high selectivity to the filling portion FL3.

[0067] When the pattern PT21 includes, for example, an organic substance, examples of substances that do not contain hydrogen, chlorine, or bromine include oxygen-containing gases, fluorine-containing gases, and nitrogen-containing gases. Examples of oxygen-containing gases include oxygen gas, carbonyl sulfide (COS) gas, and sulfur oxide (SO2) gas. Examples of fluorine-containing gases include fluorocarbons (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas and nitrogen trifluoride (NF3 gas). Examples of nitrogen-containing gases include nitrogen gas.

[0068] If the pattern PT21 contains, for example, silicon, an example of a substance that does not contain hydrogen, chlorine, or bromine includes a fluorine-containing gas. The fluorine-containing gas may contain carbon or nitrogen. An example of a fluorine-containing gas is fluorocarbon (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas and NF3 gas.

[0069] When the pattern PT21 contains a metal other than tin, for example, examples of substances that do not contain hydrogen, chlorine, or bromine include fluorine-containing gases. Examples of fluorine-containing gases include hydrogen fluoride (HF) gas, fluorocarbon (C x F y ) gas, NF3 gas, and SF6 gas. Pattern PT21 can be removed as follows: First, the surface of pattern PT21 is fluorinated using a fluorine-containing gas. Then, the fluorinated surface of pattern PT21 is exposed to a metal-containing precursor containing a metal complex. An example of a metal-containing precursor is tin(II) acetylacetonate (Sn(acac)2). Ligand exchange between the metal fluoride and the metal complex generates another highly volatile metal complex, which etches pattern PT21.

[0070] According to the method MT of this embodiment, the pattern PT21 can be inverted to the pattern PT22. Because a photoresist film containing tin is typically a negative resist film, it is difficult to reduce the dimensions of a pattern formed from a photoresist film containing tin. However, according to the method MT of this embodiment, by reducing the dimensions of the opening OP3 in the pattern PT21, a relatively small pattern PT22 can be formed. Therefore, a relatively small contact hole can be formed in the silicon-containing film 10 by etching using the pattern PT22 as a mask. Furthermore, according to the method MT of this embodiment, by using a substance that does not contain hydrogen, chlorine, or bromine in step ST3, the pattern PT21 can be selectively removed while leaving the tin-containing filler portion FL3. Tin-containing materials have the unique property of being less reactive with substances that do not contain hydrogen, chlorine, or bromine than many other materials. Therefore, using the tin-containing filler portion FL3 broadens the material options for the pattern PT21.

[0071] (Fourth embodiment) 7(a) and 7(b) and 8(a) to 8(c) are cross-sectional views showing some steps of the pattern formation method according to the fourth embodiment. Hereinafter, the method MT of the fourth embodiment will be described with reference to FIGS. 1, 5, 7, and 8.

[0072] In this embodiment, in step ST1, as shown in FIG. 7, a pattern PT31 (first pattern) having an opening OP4 is formed on a substrate W. The pattern PT31 includes a first material. In this embodiment, the first material may include at least one of an organic substance, silicon, and a metal. The first material may not include tin. Step ST1 may be performed as follows.

[0073] 5, in step ST1, first, a pattern PT21 (mask pattern) corresponding to the pattern PT31 is formed on an undercoat film UR provided on a substrate W. The pattern PT21 can be formed in the same manner as in the third embodiment.

[0074] 7, the base film UR is etched using the pattern PT21 as a mask to form a pattern PT31. For example, a pattern 14b and a pattern 16b are formed from the first layer 14 and the second layer 16, respectively. When the base film UR is etched, the pattern PT21 may disappear. The pattern PT31 may include the pattern 14b and the pattern 16b.

[0075] In step ST2, as shown in (a) and (b) of Figure 8, a filling portion FL4 is formed in the opening OP4. The filling portion FL4 includes the same second material as the filling portion FL3. Step ST2 can be performed as follows.

[0076] 8(a), a filling film FL4a to be filled in the opening OP4 is formed on the substrate W. The filling film FL4a may be formed so as to cover the pattern PT31. The filling film FL4a may be formed in the same manner as the filling film FL3a.

[0077] 8(b), if necessary, the upper part of the filling film FL4a may be removed. This forms a filling portion FL4 from the filling film FL4a. The upper part of the filling film FL4a can be removed in the same manner as the upper part of the filling film FL3a.

[0078] 8(c), by removing the pattern PT31, the filling portion FL4 remains as a pattern PT32 (second pattern) that is an inverse of the pattern PT31. The pattern PT31 is removed by etching similar to the etching of the base film UR in step ST1.

[0079] According to the method MT of this embodiment, the aspect ratio of the pattern PT32 can be made larger than that of the pattern PT22 of the third embodiment, and therefore, a good etching selectivity can be obtained when etching the oxide film 12 using the pattern PT32 as a mask.

[0080] (Fifth embodiment) 9 is a flow chart of a pattern formation method according to one exemplary embodiment. The method shown in FIG. 9 (hereinafter referred to as "method MT1") further includes steps ST4 and ST5 in addition to steps ST1, ST2, and ST3. Steps ST4 and ST5 can be performed after step ST3 in each of the first to fourth embodiments. Step ST5 can be performed after step ST4. Method MT1 will be described below.

[0081] 10(a) to 10(c) are cross-sectional views showing some steps of the pattern formation method according to the fifth embodiment. In this embodiment, steps ST4 and ST5 can be performed after step ST3 shown in FIG. 3(c).

[0082] In step ST4, as shown in FIGS. 10A and 10B, a filling portion FL11 (second filling portion) is formed in the opening OP11 of the pattern PT2. The filling portion FL11 includes a third material different from the first material and the second material. When the first material and the second material are the first material and the second material of the first embodiment, examples of the third material include organic substances, silicon, and metals (excluding tin).

[0083] Step ST4 can be performed in the same manner as step ST2. First, as shown in FIG. 10(a), a filling film FL11a to be filled in the opening OP11 is formed on the substrate W. The filling film FL11a may be formed so as to cover the pattern PT2. Next, as shown in FIG. 10(b), if necessary, the upper portion of the filling film FL11a is removed by, for example, etching or CMP. This forms a filling portion FL11 from the filling film FL11a.

[0084] 10(c), by removing the pattern PT2, the filling portion FL11 remains as a pattern PT3 (third pattern) corresponding to the pattern PT1. The step ST5 can be performed in the same manner as the step ST3.

[0085] When the pattern PT2 contains an organic material and the filling portion FL11 contains a metal other than tin or silicon, the pattern PT2 can be removed by an oxygen-containing gas or a nitrogen-containing gas. Examples of the oxygen-containing gas include oxygen gas, carbonyl sulfide (COS) gas, and sulfur oxide (SO2) gas. Examples of the nitrogen-containing gas include nitrogen gas.

[0086] When the pattern PT2 contains silicon and the filling portion FL11 contains an organic material, the pattern PT2 can be removed by a halogen-containing gas. Examples of the halogen-containing gas include fluorocarbons (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas, NF3 gas, hydrogen fluoride gas, hydrogen chloride gas and hydrogen bromide gas.

[0087] When the pattern PT2 contains silicon and the filling portion FL11 contains a metal other than tin, the pattern PT2 can be removed by a fluorine-containing gas. Examples of the fluorine-containing gas include fluorocarbons (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas and NF3 gas.

[0088] When the pattern PT2 contains a metal other than tin and the filling portion FL11 contains an organic material or silicon, the pattern PT2 can be removed using a hydrogen-containing gas or a halogen-containing gas. Examples of the hydrogen-containing gas include hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, and hydrogen gas. Examples of the halogen-containing gas include chlorine gas and bromine gas.

[0089] According to the method MT1 of this embodiment, it is possible to form a pattern PT3 that contains a different material from the pattern PT1 and has the same shape as the pattern PT1.

[0090] (Sixth embodiment) Fig. 11 is a flow chart of a pattern formation method according to one exemplary embodiment. The method shown in Fig. 11 (hereinafter referred to as "method MT2") further includes steps ST6 and ST7 in addition to steps ST1, ST2, and ST3. Steps ST6 and ST7 can be performed before step ST1 in each of the first to fourth embodiments. Step ST6 can be performed before step ST7. Method MT2 will be described below.

[0091] 12(a) to 12(c) are cross-sectional views showing some steps of the pattern formation method according to the sixth embodiment. In this embodiment, steps ST6 and ST7 can be performed before step ST1 shown in FIG. 5(c).

[0092] In step ST6, as shown in FIG. 12(a), a pattern PT4 (third pattern) having an opening OP12 is formed on the substrate W. The pattern PT4 includes a third material different from the first material and the second material. When the first material and the second material are the first material and the second material of the third embodiment, examples of the third material include organic materials, silicon, and metals (excluding tin). Step ST6 can be performed in the same manner as step ST1.

[0093] In step ST7, a filling portion FL12 (second filling portion) is formed in the opening OP12 of the pattern PT4. The filling portion FL12 includes the first material.

[0094] Step ST7 can be performed in the same manner as step ST2. First, as shown in FIG. 12(b), a filling film FL12a to be filled in the opening OP12 is formed on the substrate W. The filling film FL12a may be formed so as to cover the pattern PT4. Next, as shown in FIG. 12(c), if necessary, the upper portion of the filling film FL12a is removed by, for example, etching or CMP. This forms the filling portion FL12 from the filling film FL12a.

[0095] After step ST7, in step ST1, the pattern PT4 is removed, so that the filling portion FL12 remains as a pattern PT21 (first pattern), as shown in FIG. 5(c).

[0096] When the pattern PT4 contains an organic material and the filling portion FL12 contains a metal other than tin or silicon, the pattern PT4 can be removed by an oxygen-containing gas or a nitrogen-containing gas. Examples of the oxygen-containing gas include oxygen gas, carbonyl sulfide (COS) gas, and sulfur oxide (SO2) gas. Examples of the nitrogen-containing gas include nitrogen gas.

[0097] When the pattern PT4 contains silicon and the filling portion FL12 contains an organic material, the pattern PT4 can be removed by a halogen-containing gas. Examples of the halogen-containing gas include fluorocarbons (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas, NF3 gas, hydrogen fluoride gas, hydrogen chloride gas and hydrogen bromide gas.

[0098] When the pattern PT4 contains silicon and the filling portion FL12 contains a metal other than tin, the pattern PT4 can be removed by a fluorine-containing gas. Examples of the fluorine-containing gas include fluorocarbons (C x F y ) gas, hydrofluorocarbon (C x H y F z ) gas and NF3 gas.

[0099] When the pattern PT4 contains a metal other than tin and the filling portion FL12 contains an organic material or silicon, the pattern PT4 can be removed using a hydrogen-containing gas or a halogen-containing gas. Examples of the hydrogen-containing gas include hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, and hydrogen gas. Examples of the halogen-containing gas include chlorine gas and bromine gas.

[0100] According to the method MT2 of this embodiment, it is possible to form a pattern PT22 that contains a different material from the pattern PT4 and has the same shape as the pattern PT4.

[0101] In each embodiment, the tin-containing pattern may be a Sn-containing film. The Sn-containing film may be formed by a dry process or a wet process. The Sn-containing film may be a Sn film or a SnO film. The Sn-containing film may be a photoresist film or a non-photoresist film. The tin-containing pattern may be formed from any one of a CVD film, an ALD film, and a PVD film. The tin-containing pattern may be formed by CVD or ALD using, for example, t-butyltris(dimethylamino)tin as a precursor and, for example, H2O as an oxidizer. The CVD film, the ALD film, and the PVD film may be formed by plasma energy. The CVD film and the ALD film may be formed by thermal energy. The CVD film or the ALD film may be a tin-containing photoresist film. The photoresist film may be a photoresist film for EUV exposure. When the unexposed portion of the photoresist film contains tin and the exposed portion of the photoresist film contains tin oxide, the oxygen concentration in the exposed portion may be higher than the oxygen concentration in the unexposed portion. The unexposed portion may not contain oxygen.

[0102] 13 is a diagram schematically illustrating an apparatus for performing a pattern formation method according to one example embodiment. The method MT of each of the above-described embodiments can be performed using the apparatus 100 shown in FIG. 13. The apparatus 100 can include a coater / developer 110, an exposure apparatus 120, a coater 130, an etcher 140, an asher 150, and an etcher 160.

[0103] The coating and developing apparatus 110 and the exposure apparatus 120 may constitute a pattern forming apparatus 101. The substrate W may be transported between the coating and developing apparatus 110 and the exposure apparatus 120. The process ST1 may be performed using the pattern forming apparatus 101. In the process ST1, a pattern PT1, a pattern PT11, a pattern PT21, or a pattern PT31 may be formed using the pattern forming apparatus 101. After the process ST1, the substrate W may be transported from the coating and developing apparatus 110 to the coating apparatus 130.

[0104] Step ST2 may be performed using a coating apparatus 130 and an etching apparatus 140. The coating apparatus 130 may be, for example, a spin coater or a slit coater. The apparatus 100 may include a CVD apparatus instead of the coating apparatus 130. The apparatus 100 may include a CMP apparatus instead of the etching apparatus 140. In step ST2, the substrate W may be transported from the coating apparatus 130 to the etching apparatus 140. In step ST2, filling portions FL1, FL2, FL3, and FL4 may be formed. After step ST2, the substrate W may be transported from the etching apparatus 140 to the asher 150.

[0105] Step ST3 may be performed using an asher 150. The apparatus 100 may include a cleaning apparatus instead of the asher 150. In step ST3, the pattern PT1, pattern PT11, pattern PT21, or pattern PT31 may be removed using the asher 150. As a result, pattern PT2, pattern PT12, pattern PT22, or pattern PT32 may be formed. After step ST3, the substrate W may be transferred from the asher 150 to an etching apparatus 160. The etching apparatus 160 may be used to etch the oxide film 12 of the substrate W.

[0106] FIG. 14 is a diagram schematically illustrating an apparatus for performing a pattern formation method according to another exemplary embodiment. The method MT of each of the above-described embodiments may be performed using the apparatus 200 shown in FIG. 14. Using the apparatus 200, the method MT of each of the embodiments can be performed using only a dry process. The apparatus 200 may include a CVD apparatus 210, an exposure apparatus 220, an etching apparatus 230, a CVD apparatus 240, an etching apparatus 250, an asher 260, and an etching apparatus 270.

[0107] The CVD apparatus 210, the exposure apparatus 220, and the etching apparatus 230 may constitute a pattern forming apparatus 201. The substrate W may be transported from the CVD apparatus 210 to the etching apparatus 230 via the exposure apparatus 220. The process ST1 may be performed using the pattern forming apparatus 201. In the process ST1, the pattern PT1, the pattern PT11, the pattern PT21, or the pattern PT31 may be formed using the pattern forming apparatus 201. After the process ST1, the substrate W may be transported from the etching apparatus 230 to the CVD apparatus 240.

[0108] Step ST2 may be performed using a CVD apparatus 240 and an etching apparatus 250. In step ST2, the substrate W may be transferred from the CVD apparatus 240 to the etching apparatus 250. In step ST2, filling portions FL1, FL2, FL3, and FL4 may be formed. After step ST2, the substrate W may be transferred from the etching apparatus 250 to the asher 260.

[0109] Step ST3 may be performed using the asher 260. After step ST3, the substrate W may be transferred from the asher 260 to the etcher 270. The etcher 270 may be used to etch the oxide film 12 of the substrate W.

[0110] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0111] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0112] FL1, FL2, FL3, FL4...filling portion, MT...method, OP1, OP2, OP3, OP4...opening, PT1...pattern (first pattern), PT2, PT12, PT22, PT32...pattern (second pattern), PT11, PT31...pattern (first pattern), PT21...pattern (first pattern), W...substrate.

Claims

1. 1. A method of forming a pattern, comprising: a step of forming a second opening by removing the negative resist film from a substrate having a first pattern including a negative resist film made of a first material and a first opening formed by removing the negative resist film, and a filling portion in which a second material is filled in the first opening; the first material includes tin; The method wherein the second material is different from the first material.

2. The method described in claim 1, wherein the first material includes tin oxide.

3. The method described in claim 1 or 2, wherein the second material includes at least one of an organic material, silicon, and a metal.

4. A method according to any one of claims 1 to 3, wherein in the step of forming the second opening, the negative resist film is removed using hydrogen bromide gas.

5. The second material includes at least one of an organic material, silicon, and a metal; 2. The method of claim 1, wherein in the step of forming the second opening, the negative resist film is removed using at least one of hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, hydrogen iodide gas, fluorine gas, chlorine gas, bromine gas, iodine gas, boron trichloride gas, helium gas, neon gas, argon gas, xenon gas, nitrogen gas, hydrocarbon gas, and methanol gas.

6. The first material comprises tin oxide, The method of claim 5 , wherein the second material comprises at least one of an organic and a silicon.

7. The method described in claim 6, wherein in the step of forming the second opening, the negative resist film is removed using at least one of hydrogen bromide gas and hydrocarbon gas.

8. The second material comprising tin oxide, the oxygen concentration of the second material is higher than the oxygen concentration of the first material; 2. The method of claim 1, wherein in the step of forming the second opening, the negative resist film is removed using at least one of hydrogen fluoride gas, hydrogen chloride gas, hydrogen bromide gas, hydrogen iodide gas, fluorine gas, chlorine gas, bromine gas, iodine gas, boron trichloride gas, helium gas, neon gas, argon gas, xenon gas, nitrogen gas, hydrocarbon gas, and methanol gas.

9. The method according to claim 1, wherein the negative resist film is formed from a CVD film or an ALD film.

10. The method described in claim 9, wherein the CVD film or the ALD film is a photoresist film containing tin.

11. The method described in claim 10, wherein the photoresist film is a photoresist film for EUV exposure.

12. The substrate includes a base film, The method according to any one of claims 1 to 11, wherein the first pattern and the filling portion are formed on the underlayer.

13. The method described in claim 12, wherein the base film comprises an organic film.

14. A method as described in claim 12 or 13, further comprising a step of etching the base film using a second pattern including the filling portion and the second opening as a mask.

15. A substrate having a first pattern with a negative resist film made of a first material and a first opening formed by removing the negative resist film, and a filling portion in which a second material is filled in the first opening, the substrate including an asher or cleaning device for forming a second opening by removing the negative resist film; the first material includes tin; The device, wherein the second material is different from the first material.

16. The apparatus described in claim 15, further comprising an application device or CVD device for filling the second material into the first opening and forming the filling portion.

17. The apparatus of claim 16, further comprising a first etching apparatus or CMP apparatus for removing a portion of the filling portion.

18. A CVD device for filling the second material into the first opening and forming the filling portion; a first etching device for removing a portion of the filling portion; 16. The apparatus of claim 15, further comprising:

19. The substrate includes an undercoat film, the first pattern and the filling portion are formed on the base film, The apparatus according to any one of claims 15 to 18, further comprising a second etching device that etches the base film using a second pattern including the filling portion and the second opening as a mask.

20. A process of preparing a substrate having a base film and a target film formed on the base film, the target film including a first material and a second material different from the first material, the first material being an exposed tin-containing negative resist material; removing the first material with a process gas to form a pattern of the second material on the underlayer; A pattern forming method comprising the steps of:

21. An apparatus for processing a substrate having an undercoat film and a target film formed on the undercoat film, comprising: the target film includes a first material and a second material different from the first material, the first material being an exposed tin-containing negative resist material; The apparatus is configured to remove the first material with a process gas to form a pattern of the second material on the underlying film.

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