JP2019040201A - Pattern forming method - Google Patents

Abstract

To provide a production method of a resist composition, by which a resist composition with reduced coating defects can be produced.SOLUTION: A production method of a resist composition to be used in a process of manufacturing a semiconductor device is provided. The method comprises steps of cleaning a production apparatus for the resist composition with a cleaning liquid, extracting the cleaning liquid from the production apparatus and analyzing, cleaning the production apparatus until the concentration of a metal component included in the cleaning liquid is decreased to 5 ppb or less, and then producing the resist composition by the production apparatus.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a resist composition used for microfabrication in a manufacturing process of a semiconductor device including a semiconductor element, particularly a method for manufacturing a resist film forming composition (resist composition) used in a multilayer resist method, and the resist. The present invention relates to a pattern forming method using a resist composition manufactured by a method for manufacturing a composition.

  Along with the high integration and high speed of LSI, the circuit pattern dimension is rapidly miniaturized. Along with this miniaturization, the lithography technology has achieved the formation of a fine pattern by shortening the wavelength of the light source and appropriately selecting the resist composition corresponding thereto.

  However, in the case of miniaturization with the same light source, when the film thickness of the photoresist film to be used is miniaturized, that is, when the pattern width is made smaller, the aspect ratio of the photoresist pattern after development becomes larger, resulting in a pattern Collapse occurs. For this reason, the photoresist film thickness has been reduced with the miniaturization so that the aspect ratio of the photoresist pattern falls within an appropriate range. However, the thinning of the photoresist film has further caused a problem that the accuracy of pattern transfer to the workpiece is lowered.

  One method for solving such problems is a multilayer resist method. In this method, a photoresist film, that is, a lower layer film whose etching selectivity is different from that of the resist upper layer film is interposed between the resist upper layer film and the workpiece, a pattern is obtained on the resist upper layer film, and then the upper layer resist pattern is etched into the etching mask. In this method, the pattern is transferred to the lower layer film by etching, and further, the pattern is transferred to the workpiece by etching using the lower layer film as an etching mask.

  The silicon-containing resist underlayer film and organic underlayer film used in such a multilayer resist method usually contain metal impurities derived from the environment, equipment, equipment, and raw materials. In the patterning process using this multilayer resist method, pattern transfer by dry etching is repeated, and thus such metal impurities are transferred to a workpiece for a semiconductor device as an etching mask under dry etching conditions. When a semiconductor device is used, the circuit shows an electrical abnormality such as an open abnormality or a short abnormality, which is one of the causes of a decrease in the yield of the semiconductor device. At present, in order to prevent this, purification of raw materials is said to be most effective. For example, a method as disclosed in Patent Document 1 is disclosed that the raw material polymer can be purified by contact with an acidic aqueous solution. However, purification of the polymer alone is not sufficient for a resist composition used in a state-of-the-art process that requires fine processing and the like.

International Publication No. 2011/125326

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a method for producing a resist composition capable of producing a resist composition with reduced coating defects.

In order to solve the above problems, the present invention provides:
A method for producing a resist composition used in a semiconductor device production process,
The resist composition manufacturing apparatus is washed with a cleaning liquid, the cleaning liquid is taken out from the manufacturing apparatus, analyzed, and washed until the concentration of the metal component contained in the cleaning liquid is 5 ppb or less. A method for producing a resist composition for producing a resist composition is provided.

  Unless the concentration of the metal component contained in the production apparatus for resist production is low, a resist composition having a low metal component content, that is, a low-defect resist composition cannot be produced. If the cleaning is performed until the metal component in the cleaning solution for cleaning the inside of the manufacturing apparatus is 5 ppb or less, it is possible to manufacture a resist composition that can reduce coating defects derived from the metal component.

  At this time, in the analysis of the cleaning liquid, it is preferable to calculate the concentration of the metal component using any one of an inductively coupled plasma mass spectrometer, an inductively coupled plasma emission analyzer, and an atomic absorption analyzer.

  By analyzing the cleaning liquid using such an analyzer, the metal component in the cleaning liquid can be detected with very high sensitivity, and the concentration can be accurately calculated.

  Moreover, it is preferable to wash | clean until the sum total of the density | concentration of iron, chromium, and nickel is 2 ppb or less among the metal components contained in the said washing | cleaning liquid.

  Among the metal components contained in the cleaning solution, those that have the greatest effect on the occurrence of defects in the etching process include iron, chromium, and nickel. By reducing these metal components, etching during the etching process can be performed more. This can be ensured as a resist composition manufacturing apparatus in which defects are reduced.

  At this time, it is preferable to use an organic resist composition having an aromatic compound as a repeating unit as the resist composition.

  Among these, the aromatic compound preferably contains any one or more of a phenol derivative, a naphthalene derivative, a naphthol derivative, an anthracene derivative, and a pyrene derivative.

  Moreover, it is preferable that the said organic resist composition contains the compound and solvent which are obtained by reacting a phenol derivative, a naphthol derivative, or both, and an aldehyde derivative.

  Examples of the resist composition produced by the production method of the present invention include an organic resist composition having the above structure.

  At this time, it is preferable to use a silicon-containing resist composition as the resist composition.

  The silicon-containing resist composition preferably contains polysiloxane.

  The silicon content in the silicon-containing resist composition is preferably 10% or more.

  Examples of the resist composition produced by the production method of the present invention include a silicon-containing resist composition having the above structure.

The present invention also provides:
A method of forming a pattern on a workpiece using a resist composition produced by the method for producing a resist composition,
An organic underlayer film is formed on the workpiece using the organic resist composition produced by the production method, and a silicon-containing resist underlayer film is produced on the organic underlayer film using the silicon-containing resist composition produced by the production method. A resist upper layer film is formed on the silicon-containing resist lower layer film, a pattern is formed on the resist upper layer film, and a pattern is formed on the silicon-containing resist lower layer film using the resist upper layer film on which the pattern is formed as a mask. Transfer the pattern to the organic underlayer film using the silicon-containing resist underlayer film to which the pattern is transferred as a mask, and further transfer the pattern to the workpiece using the organic underlayer film to which the pattern is transferred as a mask. A pattern forming method is provided.

  In such a pattern formation method, pattern transfer is performed using a resist composition with reduced coating defects, so that even a fine pattern has reduced etching defects, which increases the yield in manufacturing semiconductor devices. Can be improved.

  At this time, it is preferable to use, as the organic resist composition, a resist composition manufactured by the above-described method for manufacturing a resist composition.

  If it is the pattern formation method using such an organic resist composition, a semiconductor device with a favorable yield can be manufactured.

  Moreover, it is preferable to use the resist composition manufactured by the manufacturing method of the above-mentioned resist composition as said silicon-containing resist composition.

  If it is the pattern formation method using such a silicon-containing resist composition, a semiconductor device with a favorable yield can be manufactured.

  At this time, the object to be processed is a semiconductor substrate, or a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxycarbide film, or a metal oxynitride film is formed on the semiconductor substrate. It is preferable that

  The metal constituting the workpiece is silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum, or an alloy thereof. Preferably there is.

  In the present invention, such a material can be used as a workpiece to form a pattern.

  If it is the manufacturing method of the resist composition of this invention, the resist composition in which the coating defect was reduced can be manufactured. The resist composition thus produced can be transferred without etching defects when transferred using an etching process. Therefore, it can be suitably used in the multilayer resist method, particularly for immersion exposure, double patterning, organic solvent development, etc., and finally the yield in the manufacture of semiconductor devices can be improved.

It is a flowchart which shows an example of the manufacturing method of the resist composition of this invention. It is the schematic which shows an example of the manufacturing apparatus of the resist composition used by this invention.

  In recent years, further refinement of circuit patterns of semiconductor devices has further progressed, and refinement of upper resist patterns has also progressed. As performance required for silicon-containing resist underlayer films and organic underlayer films used in multilayer resist processes, A coating film with fewer defects at the time of etching than before has been demanded.

  The present inventors have intensively investigated the origin of the metal impurities contained in the resist film that is the cause of the etching defects, and not only the raw material of the resist composition but also the metal impurities derived from the environment and the manufacturing equipment have an effect on the etching defects It has become clear that there are many cases that cause this. This metal impurity becomes a coating defect when it is used as a coating film, and is transferred as an etching defect to a semiconductor substrate by dry etching. When a semiconductor device is used, an electrical abnormality such as an open abnormality or a short abnormality occurs in a circuit. This is one of the causes of a decrease in the yield of the semiconductor device. Therefore, the present inventors have repeatedly studied to reduce such defects, and when the resist composition is manufactured until the metal component in the cleaning liquid that has cleaned the manufacturing apparatus is less than a certain amount, the coating defects The present inventors have found that it is possible to produce a resist composition that can stably form a resist film with a low content, and have completed the present invention.

That is, the present invention
A method for producing a resist composition used in a semiconductor device production process,
The resist composition manufacturing apparatus is washed with a cleaning liquid, the cleaning liquid is taken out from the manufacturing apparatus, analyzed, and washed until the concentration of the metal component contained in the cleaning liquid is 5 ppb or less. It is a manufacturing method of the resist composition which manufactures a resist composition.
Hereinafter, the present invention will be described with reference to the drawings.

FIG. 1 is a flowchart showing an example of a method for producing a resist composition of the present invention.
First, in the step (a), a resist composition is manufactured in advance with a manufacturing apparatus 10 as shown in FIG.
The production apparatus 10 includes a preparation tank 1 having a stirrer 2 and a supply port 6, a liquid feed pump 3 connected from the preparation tank 1 through a pipe having a tank valve V 1, and a cleaning liquid or a resist composition sent out from the liquid feed pump 3. A filter 4 for filtering and an extraction valve V2 for supplying the resist composition filtered by the filter 4 to the product container 5 are provided for circulating the cleaning liquid supplied from the supply port 6 of the preparation tank 1 at the time of cleaning. A circulation valve V3 and piping for passing the cleaning liquid are provided. Among these, the filter 4 may be provided with a production filter for the purpose of removing foreign substances, or a filter different from the filter used for washing is used for production. It may be exchanged.

  In the manufacturing apparatus 10 after the resist composition has been manufactured in advance in the step (a), the residual liquid from the previous manufacturing and the metal components derived from the manufacturing apparatus and the environment remain.

  Next, in the step (b), the manufacturing apparatus 10 is cleaned with a cleaning liquid. Thereby, the residual liquid and metal component in the preparation tank 1 and each piping are wash | cleaned and removed. In the step (b), it is preferable that a production filter is installed in the filter 4 or the production filter used in the step (a) is replaced for the purpose of increasing the cleanliness.

  As the cleaning liquid, one containing at least one selected from the group consisting of water, an organic solvent, an acidic solvent, and a basic solvent is preferably used. In particular, water alone or a cleaning liquid containing an organic solvent is often used.

  Examples of the organic solvent include alcohols such as methanol, ethanol, propanol, butanol, methoxyethanol, butoxyethanol, methoxypropanol, and ethoxypropanol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether. , Ether type such as propylene glycol ethyl ether, ester type such as ethyl acetate, butyl acetate, ethyl lactate, ethyl cellosolve acetate, propylene glycol methyl ether acetate, gamma butyrolactone, aromatic compounds such as benzene, toluene, xylene, dichloromethane, dichloroethane , Chlorine such as dichloroethylene, trichlorethylene Hydrocarbons can be exemplified, but preferably, alcohols such as methanol, ethanol, propanol, butanol, methoxyethanol, butoxyethanol, methoxypropanol and ethoxypropanol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, tetrahydrofuran, dioxane and ethylene Ether systems such as glycol dimethyl ether, diethylene glycol dimethyl ether, and propylene glycol ethyl ether, and ester systems such as ethyl acetate, butyl acetate, ethyl lactate, ethyl cellosolve acetate, propylene glycol methyl ether acetate, and gamma butyrolactone can be used.

  Moreover, you may use what contained water in said organic solvent as a washing | cleaning liquid. When water is contained, cleaning of water-soluble components and the like that are difficult to remove by cleaning only with an organic solvent can be promoted.

  Furthermore, you may add a volatile acid, a base, and surfactant as an additive to the washing | cleaning liquid which consists of either an organic solvent, the mixed solvent of an organic solvent and water, or water. By adding such an additive, it is possible to exfoliate solids and metal components that are difficult to remove with only an organic solvent or water from the surface of equipment such as a manufacturing apparatus, and promote cleaning.

Next, in the step (c), the cleaning liquid is taken out from the manufacturing apparatus 10.
Examples of a method for taking out the cleaning liquid from the manufacturing apparatus 10 shown in FIG. 2 include a method for extracting the cleaning liquid by opening the extraction valve V <b> 2 and collecting the cleaning liquid from the supply port 6 of the preparation tank 1.

Next, in the step (d), the taken-out cleaning liquid is analyzed, and the concentration of the metal component is calculated.
This metal component is contained in the cleaning solution for cleaning the resist composition manufacturing apparatus, and is derived from each apparatus of the manufacturing apparatus or from the environment outside the apparatus that flowed into the apparatus in the previous manufacturing. Can be listed. Specific examples include iron, chromium, nickel, sodium, magnesium, aluminum, potassium, calcium, copper, and zinc.

  At this time, the lower the concentration of the metal component in the cleaning solution for cleaning the manufacturing apparatus, the higher the cleanliness. However, in practice, it is extremely difficult to make it zero, and substantially less than 5 ppb, especially The total of iron, chromium, and nickel, which are likely to affect the occurrence of defects in the etching process, is preferably 2 ppb or less. When the concentration of the metal component is 5 ppb or less, it is possible to obtain a resist composition with fewer coating defects than in the past.

  In the present invention, in the analysis of the cleaning liquid, an inductively coupled plasma mass spectrometer (ICP-MS), an inductively coupled plasma emission spectrometer (ICP-AES), or an atomic absorption spectrometer (AAS) is used as the analyzer. It is preferable to calculate the concentration of the component. When ICP-MS, ICP-AES, and AAS are used as an analyzer, the detection accuracy can be accurately calculated up to 0.01 ppb, and as a method for confirming the cleanliness in the analysis of the cleaning liquid in the present invention. It can be used suitably.

  When the concentration of the metal component calculated in step (d) is greater than 5 ppb (> 5 ppb), cleaning with the cleaning liquid in step (b), removal of the cleaning liquid in step (c), and cleaning liquid in step (d) Analyze (calculate the concentration of non-volatile components) again. The above process is repeated until the concentration of the nonvolatile component becomes 5 ppb or less. If the concentration of the nonvolatile component is 5 ppb or less (≦ 5 ppb), the process can proceed to the next step (e).

  In the step (e), the resist composition is manufactured by the manufacturing apparatus that has performed the above-described cleaning. The raw material of the resist composition is supplied from the supply port 6 to the preparation tank 1, mixed, homogenized and prepared.

  The method for producing a resist composition of the present invention can be applied to any resist composition used for lithography, but in particular, for forming an organic resist composition for forming an organic underlayer film or a silicon-containing resist underlayer film. It can be suitably used for the production of a silicon-containing resist composition.

  Of these, the organic resist composition preferably has an aromatic compound containing at least one of a phenol derivative, a naphthalene derivative, a naphthol derivative, an anthracene derivative, and a pyrene derivative as a repeating unit, and a phenol derivative or a naphthol derivative or Particularly preferred are those containing a compound obtained by reacting both of them with an aldehyde derivative and a solvent. Specific examples of such an organic resist composition include those described in JP2012-145897A and JP2013-253227A.

  The silicon-containing resist composition preferably contains polysiloxane, and particularly preferably contains 10% or more of silicon. Specific examples of such a silicon-containing resist composition include those described in Japanese Patent No. 4716037.

Foreign substances can be removed by passing the prepared resist composition through a filter 4 provided with a filter and passing the filter.
The pore size of the filter for production can be appropriately selected according to the cleanliness required for the product (resist composition). For example, if it is necessary to reduce coating defects, those having a pore size of 20 nm or less may be used, and those having a pore size of 10 nm or less can be used when higher cleanliness is required.

  In addition, examples of the material for the production filter include fluorocarbon, cellulose, nylon, polyester, and hydrocarbon materials. In the resist composition filtration step, a so-called Teflon (registered trademark) fluorocarbon is used. Filters made of nylon, hydrocarbons such as polyethylene and polypropylene, and nylon are preferably used.

  Thereafter, the extraction valve V2 is released, and the prepared and filtered resist composition is supplied to the product container 5 to complete the resist composition manufacturing process. If necessary, the cleanliness of the resist composition may be inspected before being supplied to the product container 5.

  If it is the manufacturing method of such a resist composition, the cleanliness in a manufacturing apparatus can be measured more correctly than the conventional method, and it is manufactured by washing until the metal component in the cleaning liquid becomes a certain amount or less. Since the metal component in the apparatus can be reliably removed by washing, a resist composition with reduced coating defects can be produced.

The present invention also provides:
A method of forming a pattern on a workpiece using a resist composition produced by the above-described method for producing a resist composition,
An organic underlayer film is formed on the workpiece using the organic resist composition produced by the production method, and a silicon-containing resist underlayer film is produced on the organic underlayer film using the silicon-containing resist composition produced by the production method. A resist upper layer film is formed on the silicon-containing resist lower layer film, a pattern is formed on the resist upper layer film, and a pattern is formed on the silicon-containing resist lower layer film using the resist upper layer film on which the pattern is formed as a mask. Transfer the pattern to the organic underlayer film using the silicon-containing resist underlayer film to which the pattern is transferred as a mask, and further transfer the pattern to the workpiece using the organic underlayer film to which the pattern is transferred as a mask. A pattern forming method is provided.

  As the object to be processed, any of a semiconductor substrate, a layer to be processed (processed part) on the semiconductor substrate, a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxycarbide film, or a metal oxynitride film A film or the like that has been formed can be used.

As the semiconductor substrate, a silicon substrate is generally used, but is not particularly limited. Si, amorphous silicon (α-Si), p-Si, SiO ₂ , SiN, SiON, W, TiN, Al, etc. A material different from the layer to be processed may be used.
In addition, as a metal constituting a workpiece (including a semiconductor substrate), silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, Or any of these alloys or alloys thereof can be used. Examples of the processing layer containing such a metal include Si, SiO ₂ , SiN, SiON, SiOC, p-Si, α-Si, and TiN. , WSi, BPSG, SOG, Cr, CrO, CrON, MoSi, W, W-Si, Al, Cu, Al-Si and the like, and various low dielectric films and etching stopper films thereof are usually used. It can be formed to a thickness of 000 nm, in particular 100 to 5,000 nm.

  The organic resist composition is manufactured by the above-described manufacturing method, and has an aromatic compound containing any one or more of a phenol derivative, a naphthalene derivative, a naphthol derivative, an anthracene derivative, and a pyrene derivative as a repeating unit. Particularly preferred are those containing a compound obtained by reacting a phenol derivative and / or naphthol derivative or both with an aldehyde derivative and a solvent.

  Such an organic resist composition can be formed as an organic underlayer film on a workpiece by using a spin coat method or the like. Moreover, when a resist upper layer film forms a pattern by exposure, what expresses sufficient antireflection film function as an organic lower layer film is preferable. By forming such an organic underlayer film, the pattern formed of the resist upper layer film can be transferred onto the workpiece without causing a size conversion difference.

  The silicon-containing resist composition is produced by the above-described production method, preferably contains polysiloxane, and particularly preferably contains 10% or more of silicon. Also,

  Such a silicon-containing resist composition can be formed on the organic underlayer film by using a spin coat method or the like. In the case of forming by spin coating, it is desirable to bake in order to accelerate the crosslinking reaction for the purpose of preventing the solvent from being evaporated and mixing with the resist upper layer film after spin coating. The baking temperature is preferably in the range of 50 to 500 ° C., and the baking time is preferably in the range of 10 to 300 seconds. At this time, although it depends on the structure of the device to be manufactured, in order to reduce thermal damage to the device, 400 ° C. or lower is particularly preferable.

  In the pattern forming method of the present invention, as a method for forming a pattern on the resist upper layer film, a lithography method using light having a wavelength of 300 nm or less or EUV light, an electron beam direct writing method, a guided self-organization method (so-called Any of a DSA method and a nanoimprinting lithography method can be suitably used. By using such a method, a fine pattern can be formed on the resist upper layer film.

  In addition, you may apply the above-mentioned manufacturing method also to the composition of a resist upper layer film as needed. The resist upper layer film composition can be appropriately selected according to the method for forming a pattern on the resist upper layer film. For example, when performing lithography using light of 300 nm or less or EUV light, a chemically amplified photoresist film material can be used as the resist upper layer film composition. As such a photoresist film material, a photoresist film is formed and exposed to light, and then an exposed portion is dissolved with an alkaline developer to form a positive pattern, or a development made of an organic solvent. The thing which forms a negative pattern by melt | dissolving an unexposed part using a liquid can be illustrated.

  For example, when the exposure process in the present invention is an exposure process using ArF excimer laser light, any of the usual resist compositions for ArF excimer laser light can be used as the upper photoresist film. Many resist compositions for such ArF excimer laser light are already known. Already known resins are roughly classified into poly (meth) acrylic, COMA (Cyclo Olefin Male Anhydride), and COMA- (Metal). ) There are acrylic hybrid, ROMP (Ring Opening Polymerization), polynorbornene, and the like. Among these, resist compositions using poly (meth) acrylic resins introduce an alicyclic skeleton in the side chain. Since the etching resistance is ensured by this, the resolution performance is superior to other resin systems and can be preferably used.

  With such a pattern formation method, since there are very few coating defects in the organic underlayer film and the silicon-containing resist underlayer film, etching defects during pattern transfer in the etching process can be reduced, and when the semiconductor device is obtained In addition, it is possible to reduce electrical abnormalities such as open abnormalities and short abnormalities in the circuit. In addition, such a pattern forming method can be suitably used for immersion exposure, double patterning, organic solvent development, and the like, and finally, the yield of manufacturing semiconductor devices can be improved.

  Hereinafter, cleaning examples, comparative cleaning examples, examples, and comparative examples will be shown and described in more detail, but the present invention is not limited to these descriptions.

[Washing Example 1]
The manufacturing apparatus 10 shown in FIG. 2 was cleaned by the following procedure. A polyethylene filter cartridge having a pore diameter of 20 nm was set in the filter 4, and then 20 L of propylene glycol methyl ether acetate (hereinafter, PGMEA) was supplied as a cleaning liquid from the supply port 6 of the 100 L adjustment tank 1. After stirring with the stirrer 1 for 1 hour, the stirrer 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and PGMEA was circulated for 24 hours. The PGMEA was discharged out of the apparatus with the extraction valve V2 opened. This same operation was repeated once more, and when the PGMEA was discharged out of the apparatus, it was collected in a clean glass bottle. The concentration of the metal component in PGMEA collected using 7700s (ICP-MS) manufactured by Agilent Technologies was measured and calculated.

[Washing example 2]
Except that the pore size of the polyethylene filter cartridge set in the filter 4 is 10 nm, the concentration of the metal component is measured and calculated after washing in the same manner as in Washing Example 1 using the same configuration as in Washing Example 1. did.

[Washing Example 3]
Except that the pore size of the polyethylene filter cartridge set in the filter 4 was changed to 3 nm, the concentration of the metal component was measured and calculated after washing in the same manner as in Washing Example 1 using an apparatus having the same configuration as in Washing Example 1. did.

[Washing Example 4]
Except that the filter cartridge to be set in the filter 4 is a nylon filter cartridge having a pore diameter of 10 nm, the apparatus has the same configuration as in Cleaning Example 1, and after cleaning in the same manner as in Cleaning Example 1, the concentration of the metal component is adjusted. Measurement and calculation.

[Washing Example 5]
The filter cartridge set in the filter 4 is a Teflon (registered trademark) filter cartridge having a pore diameter of 20 nm, and is washed in the same manner as in Washing Example 1 and washed in the same manner as in Washing Example 1 The concentration of the component was measured and calculated.

[Cleaning Example 6]
Except for using a cleaning liquid of propylene glycol methyl ether (hereinafter referred to as PGME), an apparatus having the same configuration as in Cleaning Example 1 was used, and the concentration of the metal component was measured and calculated after cleaning in the same manner as in Cleaning Example 1.

[Comparative cleaning example 1]
Using the manufacturing apparatus 10 having the same configuration as the cleaning example 1, cleaning with PGMEA was performed only once (without repeating), and the concentration of the metal component was measured and calculated using the discharged PGMEA in the same manner as the cleaning example 1. .

  Table 1 shows the results of the concentrations of the metal components of the cleaning liquids collected in Cleaning Examples 1 to 6 and Comparative Cleaning Example 1.

その他の金属成分は、Ｎａ、Ｍｇ、Ａｌ、Ｋ、Ｃａ、Ｃｕ、Ｚｎである。

Other metal components are Na, Mg, Al, K, Ca, Cu, and Zn.

  Next, 16 kg of PGEE solution of 10 wt% polysiloxane having the composition shown below, 64 kg of PGEE and 8 kg of deionized water were added to the manufacturing apparatuses 10 prepared in Cleaning Examples 1 to 6 and Comparative Cleaning Example 1, respectively, and stirred for 1 hour. Thereafter, the agitator 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and circulation filtration was performed at a flow rate of 10 kg / hour for 176 hours. The resulting silicon-containing resist composition was extracted and filled in clean glass bottles as compositions S1-1 to 6 and S1-7, respectively, with the valve V2 opened.

  Furthermore, after adding the PGMEA solution 36kg of 20 weight% phenolic compounds of the composition shown below, 44kg of PGMEA, and the acid generator AG to the manufacturing apparatus 10 prepared in each of the cleaning examples 1 to 6 and the comparative cleaning example 1, the mixture was stirred for 1 hour. The agitator 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and circulation filtration was performed at a flow rate of 10 kg / hour for 144 hours. The resulting organic resist composition was extracted and filled in clean glass bottles as compositions S2-1 to 6 and S2-7, respectively, with the valve V2 opened.

  Furthermore, after adding the PGMEA solution 36kg of 20 weight% naphthol compound of the composition shown below, 44kg of PGMEA, and the acid generator AG to the manufacturing apparatus 10 prepared in each of the cleaning examples 1 to 6 and the comparative cleaning example 1, the mixture was stirred for 1 hour. The agitator 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and circulation filtration was performed at a flow rate of 10 kg / hour for 144 hours. The completed organic resist composition was extracted and filled in clean glass bottles as compositions S3-1 to S6 and S3-7, respectively, with the valve V2 opened.

  Furthermore, after adding the PGMEA solution 36kg of 20 weight% phenolic compounds of the composition shown below, 44kg of PGMEA, and the acid generator AG to the manufacturing apparatus 10 prepared in each of the cleaning examples 1 to 6 and the comparative cleaning example 1, the mixture was stirred for 1 hour. The agitator 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and circulation filtration was performed at a flow rate of 10 kg / hour for 144 hours. The completed organic resist composition was extracted and filled into clean glass bottles as compositions S4-1 to 6 and S4-7, respectively, with the valve V2 opened.

  Furthermore, after adding the PGMEA solution 36kg of 20 weight% naphthol compound of the composition shown below, 44kg of PGMEA, and the acid generator AG to the manufacturing apparatus 10 prepared in each of the cleaning examples 1 to 6 and the comparative cleaning example 1, the mixture was stirred for 1 hour. The agitator 2 was stopped, the tank valve V1 and the circulation valve V3 were opened, the extraction valve V2 was closed, the liquid feed pump 3 was started, and circulation filtration was performed at a flow rate of 10 kg / hour for 144 hours. The resulting organic resist composition was extracted and filled in clean glass bottles as compositions S5-1 to 6 and S5-7, respectively, with the valve V2 opened.

Patterning test On a silicon wafer on which a silicon nitride film having a thickness of 100 nm is formed, S2-1-7, S3-1-7, S4-1-7, and S5-1-7 are coated at 60.degree. An organic underlayer film having a thickness of 200 nm was formed by heating for 2 seconds. Next, S1-1-7 was apply | coated on it, and it heated at 240 degreeC for 60 second, and produced the silicon-containing resist underlayer film with a film thickness of 35 nm. Subsequently, an ArF resist solution (PR-1) for positive development described in Table 2 was applied and baked at 110 ° C. for 60 seconds to form a 100 nm-thick photoresist film. Further, an immersion protective film (TC-1) shown in Table 3 was applied on the photoresist film and baked at 90 ° C. for 60 seconds to form a protective film having a thickness of 50 nm.

  Next, these were exposed with an ArF immersion exposure apparatus (manufactured by Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.65, 35 degree dipole polarized illumination, 6% halftone phase shift mask), The film was baked (PEB) at 100 ° C. for 60 seconds and developed with an aqueous 2.38 mass% tetramethylammonium hydroxide (TMAH) solution for 30 seconds to obtain a 43 nm 1: 1 positive line and space pattern.

  This dimension was measured for pattern collapse with an electron microscope (CG4000) manufactured by Hitachi High-Technologies Corporation, and the cross-sectional shape was measured using an electron microscope (S-4700) manufactured by Hitachi, Ltd. (Table 4).

ArF resist polymer 1:
Molecular weight (Mw) = 7,800
Dispersity (Mw / Mn) = 1.78

Acid generator: PAG1

Base: Quencher

Protective film polymer
Molecular weight (Mw) = 8,800
Dispersity (Mw / Mn) = 1.69

  There was no problem as a result of patterning the photoresist film using the resist composition produced under any of the cleaning conditions.

Pattern Etching Test Using the resist pattern as a mask created by the above patterning test, the silicon-containing resist underlayer film is processed by dry etching under condition (1), and then dry etched under condition (2) to transfer the pattern to the organic underlayer film. Further, dry etching was performed under the condition (3), and the pattern was transferred to the silicon nitride film. The cross-sectional shape of the obtained pattern was observed with a bright field defect inspection apparatus KLA2800 manufactured by KLA-Tencor using an electron microscope (S-9380) manufactured by Hitachi, Ltd., and the results are summarized in Table 5.

(1) Etching condition equipment with CHF ₃ / CF ₄ gas: Dry etching equipment Telius SP manufactured by Tokyo Electron Ltd.
Etching conditions (1):
Chamber pressure 15Pa
Upper / Lower RF power 500W / 300W
CHF ₃ gas flow rate 50ml / min
CF ₄ gas flow rate 150ml / min
Processing time 40 sec

Etching conditions (2):
Chamber pressure 2Pa
Upper / Lower RF power 1000W / 300W
CO ₂ gas flow rate 320ml / min
N ₂ gas flow rate 80ml / min
Processing time 30 sec

Etching conditions (3):
Chamber pressure 20Pa
Upper / Lower RF power 500W / 300W
CHF ₃ gas flow rate 30ml / min
CF ₄ gas flow rate 170ml / min
Processing time 40 sec

From the above results, Examples 1 to 24 using the silicon-containing resist composition and the organic resist composition manufactured with the manufacturing apparatus cleaned until the metal component concentration in the cleaning liquid was 5 ppb or less had less than 20 defects. It became. On the other hand, Comparative Examples 5 and 6 using both the silicon-containing resist composition and the organic resist composition produced by the conventional method had 60 or more defects. Further, Comparative Examples 1 and 2 using a silicon-containing resist composition produced by the production method of the present invention and an organic resist composition produced by a conventional method, and a silicon-containing resist composition produced by a conventional method and In Comparative Examples 3 and 4 using the organic resist composition produced by the production method of the present invention, the number of defects is about 40, and fewer defects than Comparative Examples 5 and 6 using only those produced by the conventional method. Although it became a number, it became a defect number larger than Examples 1-24 using only what was manufactured with the manufacturing method of this invention.
From these facts, if the resist composition produced by the method for producing a resist composition of the present invention is used, etching defects can be reduced as compared with the conventional one, but the multilayer resist method was used in combination with the conventional one. In this case, it became clear that the effect of reducing etching defects slightly decreased. In addition, in the multilayer resist method, it has been clarified that etching defects can be greatly reduced when all the resist compositions used are manufactured by the manufacturing method of the present invention.

  Therefore, it becomes clear that the etching defect at the time of pattern transfer can be reduced by the pattern forming method using the resist composition manufactured by the method of manufacturing a resist composition of the present invention. It was suggested that the above yield can be improved.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

DESCRIPTION OF SYMBOLS 1 ... Preparation tank, 2 ... Stirrer, 3 ... Liquid feed pump, 4 ... Filter, 5 ... Product container,
6 ... Supply port, 10 ... Manufacturing equipment, V1 ... Tank valve, V2 ... Extraction valve,
V3: Circulation valve.

Claims (10)

A method for producing a resist composition used in a semiconductor device production process, comprising a preparation tank, piping, a pump, a filter, and a valve, and the preparation tank, piping, pump, filter, And the valve is cleaned by circulating the cleaning liquid, the cleaning liquid is taken out from the manufacturing apparatus and analyzed, and the cleaning liquid is circulated and cleaned until the concentration of the metal component contained in the cleaning liquid is 5 ppb or less. The cleaning liquid is discharged from the resist composition manufacturing apparatus, and then a pattern is formed on the workpiece using the resist composition manufactured by the resist composition manufacturing method in which the resist composition is manufactured by the manufacturing apparatus. A method,
An organic underlayer film is formed on the workpiece using the organic resist composition produced by the production method, and a silicon-containing resist underlayer film is produced on the organic underlayer film using the silicon-containing resist composition produced by the production method. A resist upper layer film is formed on the silicon-containing resist lower layer film, a pattern is formed on the resist upper layer film, and a pattern is formed on the silicon-containing resist lower layer film using the resist upper layer film on which the pattern is formed as a mask. Transfer the pattern to the organic underlayer film using the silicon-containing resist underlayer film to which the pattern is transferred as a mask, and further transfer the pattern to the workpiece using the organic underlayer film to which the pattern is transferred as a mask. And a pattern forming method.   2. The concentration of the metal component is calculated using any one of an inductively coupled plasma mass spectrometer, an inductively coupled plasma emission spectrometer, and an atomic absorption spectrometer in the analysis of the cleaning liquid. Pattern forming method.   The pattern forming method according to claim 1, wherein the cleaning is performed by circulating until the total concentration of iron, chromium, and nickel is 2 ppb or less among the metal components contained in the cleaning liquid.   The pattern forming method according to any one of claims 1 to 3, wherein an organic resist composition having an aromatic compound as a repeating unit is used as the organic resist composition.   The pattern forming method according to claim 4, wherein the aromatic compound includes one or more of a phenol derivative, a naphthalene derivative, a naphthol derivative, an anthracene derivative, and a pyrene derivative.   6. The pattern forming method according to claim 4, wherein the organic resist composition contains a compound obtained by reacting a phenol derivative or a naphthol derivative or both with an aldehyde derivative and a solvent.   The said silicon-containing resist composition contains polysiloxane, The pattern formation method as described in any one of Claims 1-6 characterized by the above-mentioned.   The pattern forming method according to claim 1, wherein a silicon content in the silicon-containing resist composition is 10% or more.   The workpiece is a semiconductor substrate, or a metal substrate, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxycarbide film, or a metal oxynitride film formed on the semiconductor substrate. The pattern forming method according to claim 1, wherein the pattern forming method is provided.   The metal constituting the workpiece is silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum, or an alloy thereof. The pattern formation method as described in any one of Claims 1-9 characterized by these.

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