TW201827948A - Developing solution management apparatus comprising a control means and an alarm means - Google Patents

Abstract

Provided is a developing solution management apparatus capable of realizing a development processing which is capable of maintaining desired development performance and maintaining a desired line width and residual film thickness of a wiring pattern on a substrate as well as capable of monitoring a conductivity, a dissolved photoresist agent concentration and an absorbed carbon dioxide concentration of a developing solution. The developing solution management apparatus D comprises a control means 21 and an alarm means WD. The control means 21 has a data storage portion 23 for storing conductivity data, wherein the conductivity data is the conductivity value of the developing solution, which is confirmed to have a predetermined development performance in advance, in each concentration region specified by using a dissolved photoresist agent concentration and an absorbed carbon dioxide concentration of the repeatedly used alkaline developing solution as indexes; and a control portion 31, which sends a control signal to a control valves 41-43, disposed on a pipeline for transporting a replenishing solution replenished to the developing solution, in a manner that the conductivity of the developing solution becomes a control target value by means of the conductivity value, which is stored in the data storage portion 23, of a concentration region specified by a measured value of the dissolved photoresist agent concentration and a measured value of the absorbed carbon dioxide concentration of the developing solution as the control target value. The alarm means WD sends alarm when at least one of the conductivity, the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developing solution deviates from a set management range.

Description

   Developer management device   

The present invention relates to a method and device for managing a developing solution, and more particularly to an alkaline managing developing solution that is repeatedly used for developing a photoresist film in a development process of a circuit board of a semiconductor or a liquid crystal panel. Developer management device.

In the development process of photolithography that realizes fine wiring processing such as semiconductors and liquid crystal panels, an alkaline developer (hereinafter referred to as "alkaline developer") is used as a film to be formed on a substrate. The medicinal solution on which the photoresist is dissolved.

In the manufacturing process of semiconductor or liquid crystal panel substrates, in recent years, the size of wafers or glass substrates and the miniaturization and high integration of wiring processing have made great progress. Under these circumstances, in order to realize miniaturization and high integration of wiring processing of large substrates, it is necessary to more accurately measure the concentration of the main components of the alkaline developer to maintain and manage the developer.

The measurement of the component concentration of the conventional alkaline developer is based on the fact that a good linear relationship can be obtained between the concentration of the alkaline component of the alkaline developer (hereinafter referred to as "alkaline component concentration") and the electrical conductivity ( For example, Patent Document 1).

However, in recent years, the exposure of the alkaline developer to air has increased due to the development process. Since the alkaline developer has absorbed carbon dioxide in the air, the amount of carbon dioxide absorbed by the alkaline developer has increased. When the concentration of the absorbed carbon dioxide becomes high, the conventional developer management method suffers problems such as failure to maintain a predetermined line width processing.

The reason for the above problem is that the reaction of generating carbonate due to the absorption of carbon dioxide consumes the alkaline component with developing activity in the alkaline developing solution. In addition, the reaction of generating a photoresist salt due to the dissolution of the photoresist consumes an alkaline component having a developing activity in the alkaline developing solution.

In response to the above-mentioned problems, various attempts have been made to manage the developer solution to supplement the alkaline components that have been reduced due to consumption. With regard to these attempts, the concentration of the alkaline component having a developing activity is maintained constant by measuring the carbonate concentration and supplementing the alkaline component consumed by the carbonate-producing reaction with a replenishment solution. The same applies to the alkaline components consumed by the dissolution of the photoresist. These attempts have been made from the viewpoint that the alkaline components that form carbonates and photoresist salts have lost the developing activity and are inactive (for example, Patent Document 2).

    [Prior technical literature]         [Patent Literature]    

[Patent Document 1] Japanese Patent No. 2561578

[Patent Document 2] Japanese Patent Laid-Open No. 2008-283162

However, the above-mentioned various attempts of developer management are still difficult to achieve satisfactory developer management.

The inventors of the present case have made the following findings after intensive research on developer management. That is, by managing the conductivity value of the developing solution, it is possible to realize that the carbonate and the resist salt are also partially released in the developing solution to help the developing effect, and the components that were originally considered to be inactive are The management of the developing solution assisted by the developing effect, and the management value of the conductivity of this method have various values depending on the concentration of the absorbed carbon dioxide and the concentration of the dissolved photoresist.

This is based on the fact that the basic components that form the carbonate and photoresist salt do not lose their activity, and some of them are released to assist the development, and that the alkaline components and carbonate and inhibitor salts that have development activity are released to assist the development All of the components have an effect on the conductivity. That is, the inventors of the present invention have found out that the present invention has been optimized by managing the overall conductivity of the components having a developing effect by using the conductivity value of the developing solution for management.

The present invention was developed by a researcher to solve the above problems, and an object thereof is to provide a developing solution management device capable of achieving a predetermined developing performance for a photoresist.

In order to achieve the foregoing object, the developer management device of the present invention includes a control means and an alarm means. The control means includes a data storage unit that stores electrical conductivity data, and the electrical conductivity data is based on repeated development of alkaline development. The concentration of the dissolved photoresist in the liquid and the concentration of absorbed carbon dioxide are specific, and each concentration region has a conductivity value of the aforementioned developing solution which has been confirmed to be a predetermined developing performance in advance; and a control section for using the aforementioned developing solution The measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration are stored in the data storage section in the specific concentration region as the control target value, so that the conductivity of the developing solution becomes the aforementioned control. The target value method sends a control signal to a control valve provided in the pipeline for supplying the replenishing solution to the developer; the alarm means is at least one of the conductivity of the developer, the concentration of dissolved photoresist, and the concentration of carbon dioxide absorption. An alarm is issued when any one of them deviates from the set management range.

In order to achieve the foregoing object, the developer management device of the present invention includes a control means including a data storage unit that stores conductivity data, and the conductivity data is based on the dissolution of the alkaline developer that is used repeatedly. The concentration of the photoresist and the concentration of absorbed carbon dioxide are used as indicators, and each specific concentration region has a conductivity value of the aforementioned developing solution which has been previously confirmed to have predetermined developing performance; and a control unit for dissolving the photoresist by the aforementioned developing solution. The measured value of the concentration of the agent and the measured value of the concentration of absorbed carbon dioxide, and the conductivity value stored in the data memory in a specific concentration region is used as a control target value, so that the conductivity of the developer solution becomes the control target value. A control signal is sent to a control valve provided in a pipeline for supplying a replenisher to the developer, and each of the conductivity, the dissolving photoresist concentration, and the carbon dioxide absorption concentration is provided with a conductivity and a dissolving photoresist in the developer. Alerter that alerts when the concentration of the agent and the concentration of absorbed carbon dioxide deviates from the set management range .

According to the developing solution management device of the present invention, the active components in the developing solution which are active to the developing function can be maintained regardless of the concentration of the dissolved photoresist and the concentration of carbon dioxide absorbed by the developing solution, so that the desired developing performance can be maintained. The desired line width and residual film thickness of the wiring pattern on the substrate can be maintained, and the concentration of the developing solution can be monitored.

According to a preferred aspect of the developer management device of the present invention, the developer management device includes an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights up or blinks, and a display device that displays a warning. And at least one of the relay terminals for switching the opening and closing of the contacts is used as the alarm means.

According to a preferable aspect of the developing solution management device of the present invention, it further includes a plurality of measuring devices for measuring the characteristic value of the developing solution including the developing solution, which is related to the dissolved photoresist concentration of the developing solution, and The plurality of characteristic values of the developing solution, which are related to the characteristic values of the developing solution's absorbed carbon dioxide concentration; the control means further includes a calculation unit, which is obtained from the development measured by the plurality of measuring devices The plurality of characteristic values of the liquid were measured by a multivariate analysis method to measure the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration.

According to a preferred aspect of the developing solution management device of the present invention, it further includes a plurality of measuring devices that measure the characteristic values of the developing solution including the developing solution, which are related to the dissolved photoresist concentration of the developing solution, And a plurality of characteristic values of the developing solution that are related to characteristic values of the developing solution absorbed carbon dioxide concentration; and a calculation means based on the plurality of developing solutions measured by the plurality of measuring devices For each of the characteristic values, the measured value of the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration were calculated using a multivariate analysis method.

According to a preferred aspect of the developer management device of the present invention, it includes a density meter; the control means further includes a calculation unit, which is based on the correspondence between the absorbed carbon dioxide concentration and the density of the developer, and uses the density The measured density value of the developer is measured to calculate the carbon dioxide absorption value of the developer.

According to a preferred aspect of the developer management device of the present invention, it further includes: a density meter; and a calculation means based on the correspondence between the concentration of the absorbed carbon dioxide and the density of the developer and measured by the density meter. The density value of the obtained developing solution is used to calculate the carbon dioxide absorption value of the developing solution.

According to the developer management device of the present invention, it includes control means and alarm means. The control means includes a data storage unit that stores alkali component concentration data, and the alkali component concentration data is alkaline with repeated use. The concentration of the dissolving photoresist in the developing solution has a specific absorbance and carbon dioxide concentration as indicators, and each concentration region has an alkali component concentration value of the aforementioned developing solution that has been confirmed to be a predetermined developing performance in advance; and a control section, The concentration value of the alkali component stored in the data storage unit in a specific concentration region based on the measured values of the absorbance of the developing solution and the concentration of absorbed carbon dioxide is used as a control target value so that the concentration of the alkali component of the developing solution becomes the aforementioned value. The method of controlling the target value sends a control signal to a control valve provided in a pipeline for supplying the replenishing solution to the developer; the alarm means is at least one of the alkali component concentration, absorbance, and carbon dioxide concentration of the developer. When a person deviates from the set management range, an alarm is issued.

According to the developer management device of the present invention, the control means includes a data storage unit that stores alkali component concentration data. The alkali component concentration data is based on a developer that is alkaline with repeated use. The concentration of the dissolved photoresist has a specific absorbance and carbon dioxide absorption concentration as indicators, and each concentration region has an alkali component concentration value of the aforementioned developing solution which has been confirmed to be a predetermined developing performance in advance; and a control unit for The concentration value of the alkali component stored in the data storage section in the specific concentration region of the absorbance and carbon dioxide concentration measurement values of the developer is used as a control target value, so that the alkali component concentration of the developer solution becomes the control target value. The method sends a control signal to a control valve provided in a pipeline for supplying a replenishing solution to the developing solution. Each of the alkali component concentration, absorbance, and carbon dioxide absorption concentration includes the alkali component concentration, absorbance, and absorption of the developing solution. Alarm when the carbon dioxide concentration deviates from the set management range Section.

According to a preferred aspect of the developer management device of the present invention, it is provided with an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights or flashes light, a display device that displays a warning, and At least one of the relay terminals for switching the contacts on and off is used as the aforementioned alarm means.

According to the present invention, no matter what the concentration of the photoresist is dissolved in the developing solution and the concentration of carbon dioxide is absorbed, the active components in the developing solution that are active for the development can be maintained constant, so that the desired development performance can be maintained and the development performance can be maintained. The development process of maintaining a desired line width and a residual film thickness of the wiring pattern on the substrate and monitoring the concentration of the developing solution.

A‧‧‧Development process equipment

B‧‧‧ Reservoir storage section

C‧‧‧Circulation stirring mechanism

D‧‧‧Developer management device

WD‧‧‧Alarm Means

1‧‧‧Measurement Department

11‧‧‧Conductivity meter

12‧‧‧ the first concentration measurement method

12A‧‧‧The first characteristic value measuring method

13‧‧‧Second concentration measurement method

13A‧‧‧The second characteristic value measuring method

13B‧‧‧ Density Meter

14‧‧‧ sampling pump

15‧‧‧Sampling piping

16‧‧‧Outlet side piping

21‧‧‧ Control means (e.g. computer)

23‧‧‧Data Memory Department

31‧‧‧Control Department

32, 33‧‧‧ Computing Department

36, 37‧‧‧ Computing methods

41 ~ 43‧‧‧Control Valve

44, 45, 46, 47‧‧‧ valves

61‧‧‧Developer storage tank

62‧‧‧ Overflow trough

63‧‧‧ level meter

64‧‧‧Developing chamber cover

65‧‧‧ roller conveyor

66‧‧‧ substrate

67‧‧‧Developer spray head

71‧‧‧ waste liquid pump

72, 74‧‧‧Circulation pump

73, 75‧‧‧ filters

80‧‧‧Developer solution line

81, 82‧‧‧ replenishing solution (developing solution and / or new solution)

83‧‧‧Pure water pipeline

84‧‧‧ Confluence pipeline

85‧‧‧Circulation pipeline

86‧‧‧Pipe for nitrogen

91, 92‧‧‧ replenishment solution (developing original solution and / or new solution) storage tank

FIG. 1 is a schematic diagram for explaining a developing process of the developing solution management device of the first embodiment.

FIG. 2 is a schematic diagram for explaining a developing process of the developing solution management device according to the second embodiment.

FIG. 3 is a schematic diagram for explaining a developing process of a developing solution management device according to a third embodiment.

FIG. 4 is a schematic diagram for explaining a developing process of the developing solution management device according to the fourth embodiment.

FIG. 5 is a graph showing the relationship between the concentration of absorbed carbon dioxide and the density of the developer.

FIG. 6 is a schematic diagram for explaining a developing process of a developing solution management device according to a fifth embodiment.

    [Form of Implementing Invention]    

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as appropriate. However, the shape, size, size ratio, and relative arrangement of the devices and the like described in these embodiments are not limited to the configuration of the scope of the present invention as long as there is no specific description. It is merely schematically shown as an illustrative example.

In the following description, as a specific example of the developer, a 2.38 wt% tetramethyl ammonium hydroxide aqueous solution (hereinafter, referred to as “mainly used” in a semiconductor or liquid crystal panel substrate manufacturing process is appropriately used. Tetramethylammonium hydroxide is called TMAH.). However, the developing solution to which the present invention is applicable is not limited to this. Examples of other developing solutions to which the developing solution management method and apparatus of the present invention can be applied include aqueous solutions of inorganic compounds such as potassium hydroxide, sodium hydroxide, sodium phosphate, and sodium silicate, and hydroxide Aqueous organic compounds such as trimethyl monoethanol ammonium hydroxide (choline).

In the following description, the concentration of a component such as the concentration of an alkali component, the concentration of a dissolved photoresist, and the concentration of absorbed carbon dioxide is a concentration calculated using a weight percent concentration (wt%). The so-called "dissolved photoresist concentration" means the concentration when the dissolved photoresist is converted into the amount of the photoresist, and the so-called "absorbed carbon dioxide concentration" means the concentration when the absorbed carbon dioxide is converted into the amount of carbon dioxide .

In the development process, development is performed by dissolving an unnecessary portion of the photoresist film after the exposure process with a developing solution. A photoresist salt dissolved between the photoresist dissolved in the developing solution and the alkali component of the developing solution. Therefore, if the developing solution is not appropriately managed, as the developing process proceeds, the developing solution is degraded due to the consumption of an alkaline component having developing activity, and the developing performance is deteriorated. At the same time, in the developing solution, the dissolved photoresist gradually accumulates in the form of a photoresist salt with an alkali component.

The photoresist dissolved in the developing solution exhibits an interfacial active effect in the developing solution. Therefore, the photoresist dissolved in the developing solution can improve the wettability of the photoresist film for the developing process to the developing solution, and improve the affinity between the developing solution and the photoresist film. Therefore, in a developing solution containing a photoresist moderately, the developing solution is also spread throughout the fine recesses of the photoresist film, and the photoresist film having fine unevenness can be favorably developed.

In addition, in recent years, in the development process, a large number of developing solutions are repeatedly used as the substrate becomes larger. Therefore, the opportunity for the developing solution to be exposed to the air also increases. However, once the alkaline developer is exposed to air, it absorbs carbon dioxide in the air. Carbon dioxide is absorbed between the absorbed carbon dioxide and the alkaline components of the developing solution. Therefore, if the developer is not properly managed, the alkali component having developing activity in the developer will be consumed by the absorbed carbon dioxide and reduced. At the same time, in the developing solution, the absorbed carbon dioxide gradually accumulates in the form of carbonates generated with alkaline components.

However, since the carbonate in the developing solution is alkaline in the developing solution, it has a developing effect.

As described above, unlike the previous recognition that the developing activity of the developing process is deactivated, the photoresist dissolved in the developing solution and the absorbed carbon dioxide actually contribute to the developing performance of the developing solution. Therefore, it is necessary to manage the developer solution that maintains the dissolved photoresist and carbon dioxide absorption at the optimal concentration while allowing the dissolved photoresist to be dissolved in the developer and absorb carbon dioxide, rather than dissolving the photoresist. And absorb the carbon dioxide completely remove the developer management.

The photoresist salt or carbonate generated in the developing solution is partially dissociated to generate various free ions such as photoresist ions, carbonate ions, or bicarbonate ions. In addition, these free ions can affect the conductivity of the developer at various contributing rates.

Regarding the above-mentioned points, the inventors of the present invention have made the following findings after intensive research on developer management. That is, by managing the conductivity value of the developing solution, it is possible to realize that the carbonate and the resist salt are also partially released in the developing solution to help the developing effect, and the components that were originally considered to be inactive are The management of the developing solution assisted by the developing effect, and the management value of the conductivity of this method have various values depending on the concentration of the absorbed carbon dioxide and the concentration of the dissolved photoresist.

Therefore, the inventor envisioned a case where the TMAH aqueous solution was used as a developing solution, and the concentration of the dissolved photoresist and the concentration of absorbed carbon dioxide were variously changed, and the desired developing performance of the photoresist and the conductivity of the developing solution were determined. Value relationship.

It is adjusted to change the absorbed carbon dioxide concentration between 0.0 to 1.3 (wt%) and the dissolved photoresist concentration to 0.0 to 0.40 (wt%) (equivalent to an absorbance of 0.0 to 1.3 (abs) at a wavelength of 560 nm) (the same applies to the following) A developer sample of a TMAH aqueous solution in which the concentration and the absorbance are stated in parallel). The inventors of this case conducted the following experiments: for these samples, the conductivity of the developing solution, the concentration of absorbed carbon dioxide, and the concentration of dissolved photoresist were measured, and the developing performance, the conductivity, the concentration of absorbed carbon dioxide, and the dissolved photoresist were confirmed. Relationship between concentration components. A matrix (combination table) of absorbing carbon dioxide concentration as one item arranged in the vertical or horizontal direction and dissolved photoresist concentration as another item arranged in the horizontal or vertical direction was established. For each combination of the concentration of absorbed carbon dioxide and the concentration of dissolved photoresist, the conductivity of the developing solution that satisfies the desired development performance of the photoresist is obtained, and the matrix is completed by filling in each column.

Here, the predetermined development performance refers to the development performance of the developer when the line width and the residual film thickness of the wiring pattern on the substrate to be realized in the development process are achieved.

The measurement results of the representative carbon dioxide absorption concentration, dissolved photoresist concentration, and electrical conductivity are exemplified. When the carbon dioxide concentration is 0.0 (wt%) and the dissolved photoresist concentration is 0.0 (wt%) (equivalent to 0.0 (abs)) (the so-called new liquid), the conductivity of the developing solution that can exhibit the predetermined developing performance It was 54.58 (mS / cm).

When the carbon dioxide absorption is 0.0 (wt%) and the dissolved photoresist concentration is 0.25 (wt%) (equivalent to 0.8abs), the conductivity of the developing solution that can exert the predetermined developing performance is 54.55 (mS / cm). When the dissolved photoresist concentration is 0.40 (wt%) (equivalent to 1.3 abs), the conductivity of the developing solution is 54.53 (mS / cm).

In addition, when the dissolved photoresist concentration is 0.0 (wt%) (equivalent to 0.0 (abs)) and the absorbed carbon dioxide concentration is 0.6 (wt%), the conductivity of the developing solution is 54.60 (mS / cm), and the absorbed carbon dioxide When the concentration is 1.3 (wt%), the conductivity of the developer is 54.75 (mS / cm).

When the carbon dioxide concentration is 0.6 (wt%) and the dissolved photoresist concentration is 0.22 (wt%) (equivalent to 0.7abs), the conductivity of the developer is 54.60 (mS / cm), and the photoresist is dissolved. When the concentration is 0.40 (wt%) (equivalent to 1.3 abs), the conductivity of the developer is 54.58 (mS / cm).

When the concentration of carbon dioxide absorption is 1.3 (wt%) and the dissolved photoresist concentration is 0.22 (wt%) (equivalent to 0.7abs), the conductivity of the developer is 54.75 (mS / cm), and the photoresist is dissolved in When the concentration is 0.40 (wt%) (equivalent to 1.3 abs), the conductivity of the developer is 54.75 (mS / cm).

In addition, in the above experiment, in a certain concentration region, it can be observed that when the concentration of absorbed carbon dioxide becomes larger, the management value of the conductivity tends to become larger, and when the concentration of the dissolved photoresist becomes larger, the management of the conductivity becomes larger. The value tends to become smaller.

In the experiments described above, the conductivity of the developer of each sample was a value measured using a conductivity meter. The absorbed carbon dioxide concentration is a value measured by titration analysis. The dissolved photoresist concentration is a weight modulation value. The titration is a neutralization titration using hydrochloric acid as a titration reagent. As the titration device, an automatic titration device GT-200 manufactured by Mitsubishi Chemical Analytech was used.

In addition, the above-mentioned conductivity, carbon dioxide absorption concentration, and dissolved photoresist concentration are values used to find the relationship between the conductivity, carbon dioxide absorption, dissolved photoresist concentration, and development performance, so they are not described separately. The value is limited.

As described above, it can be understood that the conductivity exhibiting the developing performance has various values depending on the concentration of the absorbed carbon dioxide and the concentration of the dissolved photoresist. In this way, in the management of the developer, in the developer containing carbon dioxide absorption and dissolution of the photoresist, the conductivity is used as the management value, and then the concentration of the carbon dioxide absorption and the dissolution of the photoresist are measured. Different management values of the electrical conductivity can achieve predetermined development performance.

That is, the conductivity data (matrix) of each concentration region specified with the concentration of the dissolved photoresist in the developer and the concentration of absorbed carbon dioxide as the developer having the conductivity value of the developer that has been confirmed to be a predetermined development performance is added. By using the conductivity data (matrix) in the memory, it is possible to perform a developer management capable of exhibiting a predetermined developing performance.

In addition, the inventors have made research on the management of the developer, and obtained the following insights: By managing the concentration value of the alkali component of the developer, it is possible to consider that the carbonate or the inhibitor salt is also partially released in the developer and help The developer function and the developer management of these components that are considered to be inactive for the development effect; and the management value of the alkali component concentration is based on the absorbance of carbon dioxide concentration and the absorbance that is related to the concentration of the dissolved photoresist. There are various values.

Therefore, the inventor envisages a case where the TMAH aqueous solution is used as a developing solution for management, so that the concentration of the alkali component measured based on the conductivity of the developing solution that is alkaline, the absorbance having a correlation with the concentration of the dissolved photoresist in the developing solution, and The concentration of carbon dioxide absorbed by the developing solution was changed variously, and the relationship between the desired developing performance for the photoresist and the concentration of the alkali component of the developing solution was determined.

A developer solution sample of a TMAH aqueous solution was prepared to change the concentration of absorbed carbon dioxide between 0.0 to 1.3 (wt%), and change the absorbance related to the dissolved photoresist concentration between 0.0 to 1.3 (abs). The inventors of this case performed the following experiments: The alkali component concentration, carbon dioxide absorption concentration, and absorbance of the developer were measured for these samples, and the development performance, alkali component concentration, carbon dioxide absorption concentration, and relationship with absorbance were confirmed. A matrix (combination table) in which the absorption carbon dioxide concentration is arranged as one item in the vertical or horizontal direction and the absorbance is arranged in the horizontal or vertical direction as the other item is prepared. For each combination of absorbed carbon dioxide concentration and absorbance, the alkali component concentration of the developing solution that satisfies the desired developing performance for the photoresist is obtained, and the matrix is completed by filling in each column.

Here, the predetermined development performance refers to the development performance of the developer when the line width or the residual film thickness of the wiring pattern on the substrate to be realized by the development process is achieved.

The measurement results of the representative carbon dioxide absorption concentration, absorbance, and alkali component concentration are exemplified. In the case where the concentration of carbon dioxide is 0.0 (wt%) and the absorbance is 0.0 (abs) (so-called new solution), the alkali component concentration of the developing solution that can exhibit a predetermined developing performance is 2.380 (wt%).

When the absorption carbon dioxide concentration is 0.0 (wt%) and the absorbance is 0.8abs, the alkali component concentration of the developing solution that can exert the predetermined development performance is 2.379 (wt%); when the absorbance is 1.3abs, the alkali component of the developing solution The concentration was 2.378 (wt%).

In addition, when the absorbance is 0.0 (abs) and the absorbed carbon dioxide concentration is 0.6 (wt%), the alkali component concentration of the developing solution is 2.381 (wt%). When the absorbed carbon dioxide concentration is 1.3 (wt%), the The alkali component concentration was 2.388 (wt%).

In addition, when the concentration of absorbed carbon dioxide was 0.6 (wt%) and the absorbance was 0.7 abs, the alkali component concentration of the developing solution was 2.381 (wt%), and when the absorbance was 1.3 abs, the alkali component concentration of the developing solution was 2.380 (wt %).

In addition, when the concentration of absorbed carbon dioxide was 1.3 (wt%) and the absorbance was 0.7 abs, the alkali component concentration of the developing solution was 2.388 (wt%). When the absorbance was 1.3 abs, the alkali component concentration of the developing solution was 2.388 (wt %).

In addition, in the above experiment, in a certain concentration region, it can be observed that when the concentration of absorbed carbon dioxide becomes larger, the management value of the alkali component concentration tends to become larger, and when the absorbance becomes larger, the management value of the alkali component concentration changes. Small tendency.

In the experiments described above, the alkali component concentration of the developer in each sample can be determined by measuring the conductivity with a conductivity meter. Specifically, a correlation (for example, a linear relationship) between the alkali component concentration of a new TMAH aqueous solution (TMAH aqueous solution before development) and the conductivity value is prepared in advance as a calibration curve. Based on this calibration curve, the alkali component concentration can be obtained from the conductivity value.

The absorbed carbon dioxide concentration is a value measured by titration analysis. Titration uses hydrochloric acid as the titration reagent for neutralization and titration. The titration device used was an automatic titration device GT-200 made by Mitsubishi Chemical Analytech. The absorbance was measured using an absorbance photometer.

The above-mentioned alkali component concentration, absorbed carbon dioxide concentration, and absorbance are used to find the relationship between the alkali component concentration, the absorbed carbon dioxide concentration, and the absorbance and the developing performance, and therefore are not limited to the respective values.

As described above, it can be understood that the concentration of the alkali component that can exert the developing performance varies depending on the concentration of carbon dioxide absorption and the absorbance. In this way, in the management of the developer, in the developer containing carbon dioxide absorption and dissolving the photoresist, the alkali component concentration is used as the management value of the developer, and then the carbon dioxide absorption concentration and absorbance are measured, and the alkali component is made based on the results of each measurement. The density management value is different, so that predetermined development performance can be exhibited.

That is, the alkali component concentration data (matrix) having the alkali component concentration value of the developing solution which has been confirmed to be a predetermined developing performance in advance is memorized in a specific concentration area using the absorbance and carbon dioxide concentration of the developing solution as indicators, By using the alkali component concentration data (matrix), predetermined development performance can be exhibited.

Next, specific embodiments will be described with reference to the drawings.

[First embodiment]

FIG. 1 is a schematic diagram for explaining a developing process of the developer management device D of this embodiment. The developing solution management device D of the present invention is shown together with the developing process equipment A, the replenishing solution storage portion B, the circulation stirring mechanism C, and the like.

First, the developing process equipment A will be described briefly.

The development process equipment A mainly includes a developer storage tank 61, an overflow tank 62, a development chamber cover 64, a roller conveyor 65, a developer nozzle 67, and the like. A developer is stored in the developer storage tank 61. The developer system receives the replenishment of the replenisher and manages the composition. The developer storage tank 61 includes a liquid level meter 63 and an overflow tank 62 to manage the increase in the amount of liquid caused by the replenishment of the replenishing liquid. The developing solution storage tank 61 is connected to the developing solution spraying head 67 through a developing solution line 80. The developer stored in the developer storage tank 61 is sent to the developer spray head 67 via a filter 73 by a circulation pump 72 provided in the developer solution line 80. The roller conveyor 65 is installed above the developer storage tank 61 and is used to transport a substrate 66 formed with a photoresist film. The developer is dripped from the developer spray head 67. The substrate 66 conveyed by the roller conveyor 65 is immersed in the developer by dropping the developer. Then, the developer is collected in the developer storage tank 61 and stored again. In this way, the developer is circulated and reused during the development process. In addition, there may be a case where the developing chamber of a small glass substrate is filled with nitrogen or the like, and a treatment that does not absorb carbon dioxide in the air is applied. In addition, the deteriorated developer is treated with waste liquid by operating the waste liquid pump 71 (drain).

The circulating stirring mechanism C will be described. The circulating stirring mechanism C is mainly used for circulating stirring of the developer stored in the developer storage tank 61.

The bottom of the developer storage tank 61 and the side of the developer storage tank 61 are connected by a circulation line 85 provided with a circulation pump 74 and a filter 75 in the middle. When the circulation pump 74 is operated, the developer stored in the developer storage tank 61 circulates through the circulation line 85. The developer is returned from the side of the developer storage tank 61 to the developer storage tank 61 via the circulation line 85, and the stored developer is stirred.

When the supplementary liquid flows into the circulation line 85 through the merging line 84, the inflowing supplemental liquid is supplied into the developer storage tank 61 while being mixed with the developer liquid circulating in the circulation line 85.

Next, the developer management device D of this embodiment will be described. The developer management device D of this embodiment is a developer management device in which each concentration region specified by using the concentration of the dissolved photoresist and the concentration of the absorbed carbon dioxide of the developer in an alkaline state has a predetermined value. Conductivity data (data) for confirming the conductivity value of the developing solution that has a predetermined developing performance, and the conductivity in the concentration range specified by the measured value of the dissolved photoresist concentration of the developing solution and the measured value of the absorbed carbon dioxide concentration As the control target value, the developer is replenished with a replenisher so that the conductivity of the developer becomes the control target value.

The developer management device D includes a measurement unit 1 and a control unit 21. The developer management device D is connected to the developer storage tank 61 via a sampling pipe 15 and an outlet-side pipe 16.

The measurement unit 1 includes a sampling pump 14, a conductivity meter 11, a first concentration measuring means 12 for measuring the concentration of the dissolved photoresist, and a second concentration measuring means 13 for measuring the concentration of the absorbed carbon dioxide. The conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 are connected in series to the rear stage of the sampling pump 14. In order to improve the measurement accuracy, it is preferable that the measurement unit 1 be further provided with a temperature adjustment means (not shown) that stabilizes the sampled developer solution at a predetermined temperature. In this case, it is preferable to set the temperature adjustment means before the measurement means. The sampling pipe 15 is connected to the sampling pump 14 of the measurement unit 1 of the developer management device D, and the outlet-side pipe 16 is connected to a pipe at the end of the measuring means.

In FIG. 1, the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 are connected in series, but the conductivity meter 11, the first concentration measuring means 12 and the first The connection of the 2 concentration measuring means 13 is not limited to this. The measurement may be performed by connecting them in parallel, or by separately providing a transport path. Regarding the order of the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13, the order of them is not particularly discussed. It is only necessary to perform the measurement in an optimal order in accordance with the characteristics of each measurement means.

The control means 21 includes a data storage section 23 and a control section 31. In the data storage section 23, conductivity data is stored, and the conductivity data is specified for each concentration region using the dissolved photoresist concentration and carbon dioxide absorption concentration of the developer as an indicator, and has been confirmed in advance. The conductivity value of the developer used will be a predetermined developing performance.

The control means 21 is connected to the conductivity meter 11, the first concentration measurement means 12, and the second concentration measurement means 13 of the measurement unit 1 via a signal line. The conductivity value measured by the measurement unit 1, the dissolved photoresist concentration value, and the absorbed carbon dioxide concentration value are transmitted to the control means 21.

The control unit 31 of the control means 21 is connected to control valves 41 to 43 provided in a pipeline for supplying the replenishing liquid to the developing liquid via a signal line. In FIG. 1, the control valves 41 to 43 are shown as internal parts of the developer management device D, but the control valves 41 to 43 are not essential parts of the developer management device D of this embodiment. The control unit 31 controls the operations of the control valves 41 to 43 and communicates with the control valves 41 to 43 so as to replenish the replenishing liquid to the developer. The control valves 41 to 43 may exist outside the developer management device D.

The developer management device D according to the embodiment includes an alarm means WD. The alarm means WD is capable of issuing an alarm when at least one of the conductivity of the developing solution, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide deviates from the set management range.

For example, by the control means 21, it can be determined whether at least any one of the conductivity of the developing solution, the dissolved photoresist concentration, and the concentration of the carbon dioxide absorption component is outside the set management range. This information is transmitted from the control means 21 to the alarm means WD, and an alarm can be issued to the alarm means WD based on the information.

As long as the alarm means WD can issue an alarm, the determination means is not limited to this.

The alarm means WD preferably includes an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights or flashes light, a display device that displays a warning, and switching contact opening and closing. At least one of the relay terminals.

When the alarm means WD is an external output signal terminal that issues an alarm signal, the external output signal terminal is connected to a device (not shown). When the device receives an alarm signal from an external output signal terminal, it can perform a predetermined action. For example, if the system includes a concentration monitoring device, the system can be stopped.

When the alarm means WD is an alarm device that emits an alarm sound, or a warning light that illuminates or flashes the light, it may attract the attention of an operator near the concentration monitoring device. The operator can confirm the status of the concentration monitoring device and take appropriate measures.

In the case where the warning means WD is a display device for displaying a warning, the operator's attention can also be attracted. In addition, when the display device is electrically connected to the computing unit 2 in a wired or wireless manner, even an operator who is far away from the concentration monitoring device can attract attention.

When the alarm means WD is a relay terminal for switching the contact on and off, the ON and OFF of the device connected to the relay terminal can be switched, and the device can perform a predetermined operation.

In addition, each of the conductivity, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration may be provided with an alarm means WD that issues an alarm when the conductivity of the developing solution, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration deviate from a set management range. The alarm means WD is provided according to each of the conductivity, the dissolved photoresist concentration, and the carbon dioxide absorption concentration. From the alarm issued by the alarm means WD, the conductivity, dissolved photoresist concentration, and carbon dioxide absorption concentration of the developing solution can be known. Which of them deviates from the scope of management.

Next, the operation of the developer management device D according to this embodiment will be described.

The developer sampled from the developer storage tank 61 is transported into the measurement unit 1 and subjected to temperature adjustment. Then, the developing solution is sent to the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 to measure the conductivity, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide. Each measurement data is transmitted to the control means 21.

The control unit 31 sets a management value of the conductivity, and the management value of the conductivity is determined in advance for each concentration region specified with the dissolved photoresist concentration of the developing solution and the concentration of the absorbed carbon dioxide as predetermined. Corresponds to the conductivity value of the developing solution. The control unit 31 performs control in the following manner based on the measurement data received from the measurement unit 1.

The control unit 31 obtains the measured dissolved photoresist concentration and the measured absorption from the conductivity data stored in the data storage unit 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration received from the measurement unit 1. Carbon dioxide concentration and conductivity value in a specific concentration range. Then, the obtained conductivity value is set as a control target value of the conductivity of the developing solution.

The control unit 31 compares the measured conductivity received from the measurement unit 1 with the conductivity set as a control target value, and performs the following management based on the comparison result. That is, when the conductivity set to the control target value is the same as the measured conductivity, the replenishing liquid is not substantially added to the developing solution. In addition, when the conductivity which is a control target value is set to be larger than the measured conductivity, it is only necessary to supply a replenishing liquid which produces an effect of improving the conductivity to a developing solution. In addition, when the conductivity which is set as the control target value is smaller than the measured conductivity, it is only necessary to replenish the developer solution with a replenishing solution that causes the conductivity to decrease.

Here, the replenishing liquid replenished to the developing solution includes, for example, an original solution or a fresh solution of the developing solution, and pure water.

The replenishment liquids are replenishment liquid storage tanks 91 and 92 stored in the replenishment liquid storage unit B. The replenishment liquid storage tanks 91 and 92 are connected to a nitrogen line 86 having valves 46 and 47, and are pressurized by nitrogen gas supplied through the lines. Further, the replenishment liquid storage tanks 91 and 92 are connected to the replenishment liquid lines 81 and 82, respectively, and the replenishment liquid is conveyed through the valves 44 and 45 which are normally opened. Control valves 41 to 43 are installed in the replenishing liquid lines 81 and 82 and the pure water line 83. The control valves 41 to 43 are controlled by the control unit 3 to be opened and closed. When the control valve operates, the replenishment liquid stored in the replenishment liquid storage tanks 91 and 92 is pressure-fed, and pure water is delivered. Then, the replenishing liquid is merged with the circulation stirring mechanism C through the merging line 84, and is replenished to the developer storage tank 61 and stirred.

When the replenishment liquid stored in the replenishment liquid storage tanks 91 and 92 decreases due to replenishment, the internal pressure will decrease and the supply amount will become unstable. Therefore, the valves 46 and 47 will be appropriately opened to supply nitrogen in response to the decrease in replenishment liquid In order to maintain the internal pressure of the replenishment liquid storage tanks 91 and 92, it is maintained. When the replenishment liquid storage tanks 91 and 92 are empty, the valves 44 and 45 are closed and exchanged with a new replenishment liquid storage tank filled with replenishment liquid, or the replenishment liquid prepared separately is refilled into the empty replenishment liquid storage groove.

The control of the control valves 41 to 43 is performed in the following manner, for example. As long as the flow rate is adjusted when the control valve is opened, the amount of replenishment liquid can be replenished by managing the opening time of the control valve. The control unit 31 sends a control signal to the control valve to open the control valve for a predetermined time based on the measured conductivity received from the measurement unit 1 and the conductivity set as the control target value, so that the amount of fluid to be replenished The make-up fluid flows.

The control method can adopt various control methods that can be used for controlling the control amount to meet the target value. In particular, proportional control (P control) (Proportional Control), integral control (I control) (Integral Control), differential control (D control) (Differential Control), and a combination of these controls (PI control, etc.) (Proportional-Integral Control) is better. PID control (Proportional-Integral-Differential Control) is very suitable and better.

As described above, according to the developing solution management device D of this embodiment, the developing solution can be managed by the conductivity of the developing solution regardless of the dissolved photoresist concentration and carbon dioxide absorption concentration of the developing solution. It maintains active ingredients for development, so it can maintain the desired development performance, and can realize the development process that can maintain the desired line width and residual film thickness of the wiring pattern on the substrate.

In addition, according to the developer management device D of this embodiment, the conductivity data of the conductivity value of the developer whose performance has been confirmed in advance is used as the control target management value, so that even if the developer has a dissolved photoresist concentration of 0.0, To 0.40 (wt%) (equivalent to 0.0 to 1.3 (abs)), and the carbon dioxide absorption concentration is 0.0 to 1.3 (wt%), it can still be used as a developing solution having a desired developing activity. That is, according to the developing solution management device D of this embodiment, even if the concentration of the dissolved photoresist in the developing solution is 0.25 (wt%) or more (equivalent to 0.8 (abs)), and the concentration of absorbed carbon dioxide is 0.6 (wt%) or more The developing solution can also be used without treatment with waste solution, and the amount of waste solution of the developing solution can be reduced.

Hereinabove, the examples using the conductivity of the developer, the concentration of absorbed carbon dioxide, and the dissolved photoresist concentration and conductivity data have been described. However, it is not limited thereto, and the developer may be managed using the alkali component concentration, carbon dioxide absorption concentration, absorbance and alkali component concentration data of the developer. In this case, the alarm means WD generates an alarm when at least one of the alkali component concentration value, absorbance, and absorbed carbon dioxide concentration of the developer deviates from the set management range.

[Second Embodiment]

FIG. 2 is a schematic diagram for explaining a developing process of the developer management device D according to this embodiment. The developing solution management device D of the present invention is shown together with the developing process equipment A, the replenishing solution storage portion B, the circulation stirring mechanism C, and the like. In addition, the same configurations as those of the first embodiment may be assigned the same reference numerals, and descriptions thereof may be omitted.

The measurement unit 1 of the developer management device D includes: a conductivity meter 11; and a plurality of measurement devices for measuring a characteristic value of the developer that is related to the dissolved photoresist concentration of the developer and a carbon dioxide concentration absorbed by the developer. There are relevant characteristics of the developer. For example, as the first characteristic value measuring means 12A for measuring the characteristic value of the developing solution related to the dissolved photoresist concentration, for example, an absorbance photometer for measuring the absorbance at λ = 560 nm is provided. As the second characteristic value measuring means 13A for measuring the characteristic value of the developing solution related to the concentration of absorbed carbon dioxide, a density meter for measuring the density of the developing solution is provided.

Here, the characteristic value of the “correlated” developer refers to a relationship in which the characteristic value is related to the concentration of the component, and the characteristic value changes in response to a change in the component concentration. For example, a characteristic value a of a developing solution in which the component concentration of the developing solution is at least related to the component concentration A means that when the characteristic value a is obtained by using the function of the component concentration as a variable, one of the variables includes at least the component Concentration A. The characteristic value a may be only a function of the component concentration A, but in general, in addition to the component concentration A, it is also formed as a multivariate function using the component concentration B or C as a variable, and a multivariate analysis method (for example, multiple regression analysis Law) is of great significance.

The control means 21 includes a data storage section 23, a control section 31, and a calculation section 32. The calculation unit 32 calculates the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developing solution from a plurality of characteristic values of the developing solution measured by the measuring unit 1 by a multivariate analysis method.

In this embodiment, the developer sampled from the developer storage tank 61 is transported to the measurement unit 1 and temperature-adjusted. The developer is then sent to the conductivity meter 11, the first characteristic value measuring means 12A, and the second characteristic value measuring means 13A to measure the conductivity, absorbance, and density. Each measurement data is transmitted to the control means 21.

The computing unit 32 calculates the measured value of the dissolved photoresist concentration in the developer and the measured value of the absorbed carbon dioxide concentration from the absorbance and density measured by the measuring unit 1 by a multivariate analysis method. At this time, from the conductivity, absorbance, and density, the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration can also be calculated by a multivariate analysis method.

The control section 31 obtains the measured dissolved photoresist concentration and the measured photoconductivity from the conductivity data stored in the data storage section 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the calculation section 32. The obtained carbon dioxide concentration is a conductivity value in a specific concentration range. The obtained conductivity value is set as a control target value of the developer conductivity.

The developer management apparatus D of this embodiment includes an alarm means WD. The warning means WD can issue an alarm when at least any one of the conductivity of the developing solution, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide deviates from the set management range.

Since other structures, operations, and the like are the same as those of the first embodiment, they are omitted.

Next, the method of calculating the measured value of the dissolved photoresist concentration and the carbon dioxide absorption concentration by a multivariate analysis method from a plurality of characteristic values of the developer will be described.

The inventors of the present invention have found that as long as the calculation method is a multivariate analysis method (for example, multiple regression analysis method), the concentration of each component of the developing solution can be calculated more accurately than in the case of using a conventional method, and the absorption that has been difficult to measure in the past can be measured. CO2 concentration. By using the component concentration (dissolved photoresist and concentration absorbed carbon dioxide concentration) of the developer solution calculated by a multivariate analysis method (for example, multiple regression analysis method), it is possible to dissolve the photoresist from a developer having previously confirmed development performance. The conductivity data of the agent concentration and the carbon dioxide concentration and the conductivity value can easily obtain the target conductivity value.

The inventor of the present case imagines a case where a 2.38% TMAH aqueous solution is managed, and a TMAH aqueous solution prepared by making various changes in the concentration of the alkali component, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide is used as a mock developer sample. The inventors of the present invention conducted the following experiments: from the various characteristic values measured for these simulated developer samples, the component concentrations were determined by a multiple regression analysis method. In the following, a general calculation method using a multiple regression analysis method will be described first, and then a calculation method using a multiple regression analysis method for the concentration of the developer component according to an experiment performed by the inventor will be described.

The multiple regression analysis system is composed of two stages: correction and prediction. In the multiple regression analysis of the n-component system, it is assumed that m calibration standard solutions are prepared. The concentration of the j-th component present in the i-th solution is represented as C _ij . Here, i = 1 to m and j = 1 to n. For m standard solutions, p characteristic values (for example, characteristic values such as absorbance or conductivity of a certain wavelength) A _ik (k = 1 to p) are measured. Concentration data and characteristic data can be aggregated and expressed in the form of a matrix (C, A).

The matrixes associated with such matrices are referred to as correction matrices, and are represented here with symbols S (S _kj ; k = 1 to p, j = 1 to n).

C = A. S

A matrix calculation is performed from known C and A (the content of A is a mixture of heterogeneous measurement values even if they are not purely homogeneous measurement values. For example, conductivity and absorbance and density.) S is calculated as Calibration phase. At this time, it must be p ≧ n and m ≧ np. Since each element of S is unknown, m> np is preferred. In this case, the least square operation is performed in the following manner.

Here, the superscript T means the transposed torch array, and the superscript -1 is the inverse matrix.

For p samples with unknown concentrations, determine p characteristic values. If these characteristic values are set to Au (Au _k ; k = 1 to p), multiply these characteristic values by S to obtain the required concentration Cu (Cu _j) . j = 1 to n).

Cu = Au. S

This is the prediction phase.

The inventors conducted the following experiment: The used alkaline developer (2.38% TMAH aqueous solution) was regarded as a multi-component system (n = 3) composed of 3 components, such as an alkali component, a dissolved photoresist, and carbon dioxide absorption From the three characteristic values (p = 3) which are the characteristic values of the developing solution, that is, from the conductivity value of the developing solution, the absorbance value at a specific wavelength, and the density value, the concentration of each component is calculated by the above-mentioned multiple regression analysis method. . The inventor used a 2.38% TMAH aqueous solution as the basic composition of the developer, and prepared 11 calibration standard solutions (m = 11, which have various changes in the concentration of the alkali component (TMAH concentration), the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide. p ≧ n and m> np).

The experiment is based on 11 calibration standard solutions. The conductivity value, absorbance value at wavelength λ = 560nm, and density value are used as the characteristic values of the developing solution. Multiple linear regression analysis (Multiple Linear Regression-Inverse Least Squares; MLR- ILS) calculates the concentration of each component.

Regarding the measurement method, the temperature of the calibration standard solution was adjusted to 25.0 ° C, and then performed. The temperature adjustment method is as follows: first immerse the bottle filled with the calibration standard solution in a thermostatic water tank with a temperature management near 25 ° C for a long time, take a sample, and use the temperature controller to set it to 25.0 ° C immediately before the measurement. . The conductivity meter is a conductivity meter manufactured by our company. The measurement was performed using a conductivity flow cell made by our company that had been subjected to platinum black treatment. Enter the cell constant of the conductivity flow cell that has been confirmed by the calibration operation in the conductivity meter. The absorbance photometer is also made by our company. The absorbance photometer includes a light source section, a photometric section, and a glass flow cell with a wavelength of λ = 560 nm. The density measurement uses a densitometer. The density meter uses a natural vibration method for obtaining density from a natural vibration frequency measured by exciting a U-shaped tube through a flow channel. The units of the measured conductivity value, absorbance value, and density value are mS / cm, Abs. (Absorbance), and g / cm ^{3, respectively} .

Regarding the method used in the calculation (Leave-One-Out method; Leave-One-Out method), one of the 11 calibration standard solutions is selected as the unknown sample, and the calibration matrix is calculated based on the remaining 10 standards to calculate the assumed unknown. The concentration of the sample was compared with known values (concentration values and weight modulation values measured by other correct analysis methods).

Table 1 shows the results of the MLR-ILS calculation.

Since the TMAH aqueous solution is strongly alkaline and easily deteriorates due to absorption of carbon dioxide, the concentration matrix used in the calculation when performing MLR-ILS calculations uses a titration analysis method that can accurately analyze the concentration of alkali components and the concentration of absorbed carbon dioxide. Measure the value obtained by calibrating the standard solution. However, regarding the dissolved photoresist concentration, a weight modulation value is used.

The titration method is a neutralization titration using hydrochloric acid as a titration reagent. The titration device used was an automatic titration device GT-200 made by Mitsubishi Chemical Analytech.

The density matrix is shown in Table 2 below.

Table 3 shows the measurement results of the characteristic values of the calibration standard solution at this time. The column of absorbance is the absorbance value (wavelength d = 10mm) at the wavelength λ = 560nm.

The correction matrix is shown in Table 4.

Table 5 shows a comparison between the concentration measurement values in Table 2 and the calculated MLR-ILS values in Table 1.

As shown in Table 5, the TMAH concentration, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration obtained by the multiple regression analysis method are all the same as the TMAH concentration, the absorbed carbon dioxide concentration, and the adjusted weight obtained from the titration analysis. The obtained dissolved photoresist concentration is a fairly similar value.

In this way, it was understood that by measuring the conductivity of an alkaline developing solution, the absorbance and density at a specific wavelength, and using a multivariate analysis method (for example, multiple regression analysis method), it is possible to measure the alkali component concentration and dissolving photoresist of the developing solution. Agent concentration and carbon dioxide absorption.

Multivariate analysis (for example, multiple regression analysis) has a good effect in calculating and determining the concentration of a plurality of components. A plurality of characteristic values a, b, c, ... of the developer are measured, and the component concentrations A, B, C, .. can be obtained from the measured values by a multivariate analysis method (for example, a multiple regression analysis method). .. At this time, for the required component concentration, at least one characteristic value related to the component concentration must be measured and used in the calculation.

In addition, a component concentration is a scale which shows the relative amount of the component with respect to the whole. The component concentration of a mixed solution, such as a repeatedly used developing solution, which may increase or decrease with time, cannot be determined by its components alone, and is usually a function of the concentration of other components. Therefore, the relationship between the characteristic value of the developing solution and the component concentration is often difficult to represent in a flat graph. In this case, it is not possible to calculate the component concentration from the characteristic value of the developer using an algorithm or the like using a calibration curve.

However, if a multivariate analysis method (for example, multiple regression analysis method) is used, as long as a set of measurement values of a plurality of characteristic values related to the concentration of the component to be calculated is collected, and these measurement values are used in the calculation, Calculate a set of component concentrations. Even if the component concentration is measured by a multivariate analysis method (for example, a multiple regression analysis method) based on a component concentration which is difficult to measure at a glance in the conventional knowledge, it is possible to obtain a significant component concentration that can be measured by measuring characteristic values. effect.

As described above, according to the calculation method of the present invention, the alkali component concentration and the dissolved photoresist concentration of the developing solution can be calculated from the measured values of the characteristic values of the developing solution (for example, electrical conductivity, absorbance at a specific wavelength, and density). , And absorption of carbon dioxide concentration. According to the calculation method of the present invention, the concentration of each component can be calculated with higher accuracy than the conventional method.

In addition, since a multivariate analysis method (for example, a multiple regression analysis method) is used in the present invention, in the calculation of the component concentration of the developer, a developer characteristic that is wirelessly related to the specific component concentration of the developer can be used. value.

In addition, according to the present invention, it is possible to eliminate the need for preparation and preliminary measurement of a very large number of samples for realizing high-precision measurement, which is necessary in the invention of Patent Document 2. (As in the previous experimental example, if it is a developing solution with the number of components n = 3, let the number of characteristic values for measurement be p = 3, and prepare the number of samples p that satisfy m ≧ np (for example, p = 11 samples) ) Is sufficient for measurement. If the number of components is n = 2, the number of samples can be reduced.) In addition, the present invention uses a multivariate analysis method (for example, a multiple regression analysis method), so it can be calculated with high accuracy. It is conventionally difficult to measure the absorbed carbon dioxide concentration of the developer.

In this embodiment, the characteristic value of the developing solution that is related to the dissolved photoresist concentration of the developing solution is exemplified by an absorbance of λ = 560 nm, but is not limited thereto. It is also possible to use the absorbance of other specific wavelengths as the characteristic value, that is, use the absorbance of the specific wavelength in the visible region, more preferably the specific wavelength of the 360-600 nm wavelength region, and more preferably the absorbance of the wavelength λ = 480 nm as the characteristic value. This is because there is a relatively good correspondence between the absorbance of specific wavelengths contained in these wavelength regions and the concentration of the dissolution resist.

Moreover, although the characteristic value of the developing solution related to the carbon dioxide absorption concentration of the developing solution is exemplified by density, it is not limited thereto. As for the characteristic value of the developing solution which is related to the dissolved photoresist concentration and the carbon dioxide absorption concentration of the developing solution, the characteristic value that can be measured in accordance with the conductivity of the developing solution can be, for example, a characteristic value other than the aforementioned specific wavelength. In addition to the absorbance and density, ultrasonic propagation speed, refractive index, titration end point, pH, and the like can be mentioned.

[Third Embodiment]

FIG. 3 is a schematic diagram for explaining a developing process of the developer management device D according to this embodiment. The developing solution management device D of the present invention is shown together with the developing process equipment A, the replenishing solution storage portion B, the circulation stirring mechanism C, and the like. In addition, the same configurations as those of the first embodiment and the second embodiment may be assigned the same reference numerals, and descriptions thereof may be omitted.

The developer management apparatus D according to the present embodiment includes a measurement unit 1, a control unit 21, and a calculation unit 36. Different from the second embodiment, in this embodiment, the control means 21 and the arithmetic means 36 for performing calculations are configured as separate devices.

The measurement unit 1 includes a conductivity meter 11, a first characteristic value measuring means 12A, and a second characteristic value measuring means 13A. The calculation means 36 is a method for calculating the measured value and absorption of the dissolved photoresist concentration in the developing solution by multivariate analysis from the absorbance and density measured by the first characteristic value measuring means 12A and the second characteristic value measuring means 13A. Measurement of carbon dioxide concentration. At this time, the measured value of the dissolved photoresist concentration and the absorbed carbon dioxide concentration can be calculated from the conductivity, absorbance and density by multivariate analysis.

The control unit 31 obtains the measured dissolved photoresist concentration and the measured dissolved photoresist concentration stored in the conductivity data of the data storage unit 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the calculation means. The absorption of carbon dioxide concentration and the conductivity value in a specific concentration range. The obtained conductivity value is set as a control target value of the developer conductivity.

The developer management apparatus D of this embodiment includes an alarm means WD. The warning means WD can issue an alarm when at least any one of the conductivity of the developing solution, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide deviates from the set management range.

The other configurations, operations, and the like are the same as those of the second embodiment, and are omitted.

[Fourth Embodiment]

FIG. 4 is a schematic diagram for explaining a developing process of the developer management device D according to this embodiment. The developing solution management device D of the present invention is shown together with the developing process equipment A, the replenishing solution storage portion B, the circulation stirring mechanism C, and the like. In addition, the same configurations as those of the first embodiment, the second embodiment, and the third embodiment may be assigned the same reference numerals, and descriptions thereof may be omitted.

The measurement unit 1 of this embodiment includes a conductivity meter 11, a first concentration measuring means 12, and a density meter 13B. The control means 21 includes a data storage unit 23 and a calculation unit 33. The calculation unit 33 calculates the absorbed carbon dioxide concentration of the developing solution from the density of the developing solution measured by the density meter 13B based on the correspondence between the absorbed carbon dioxide concentration and the density of the developing solution.

The control unit 31 obtains the measured conductivity of the conductivity data stored in the data storage unit 23 based on the dissolved photoresist concentration measured by the measurement unit 1 and the absorbed carbon dioxide concentration calculated by the calculation unit 33. Dissolves the photoresist concentration and the measured value of the absorbed carbon dioxide concentration to determine the conductivity value in a specific concentration range. The obtained conductivity value is set as a control target value of the developer conductivity.

The developer management apparatus D of this embodiment includes an alarm means WD. The alarm means WD can issue an alarm when at least any one of the conductivity of the developing solution, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide deviates from the set management range.

Since other structures, operations, and the like are the same as those of the first embodiment, they are omitted.

The relationship between the density value of the developer and the carbon dioxide absorption value will be described. As a result of continuous research, the inventors obtained the following findings. That is, regardless of the concentration of the alkali component of the developing solution and the concentration of the dissolved photoresist, a relatively good correspondence relationship (linear relationship) can be obtained between the density value of the developing solution and the value of the absorbed carbon dioxide concentration. In addition, by using this correspondence relationship (linear relationship), by measuring the density of the developing solution with a density meter, it is possible to measure the absorbed carbon dioxide concentration which was difficult to measure in the past.

The inventor conducted the following experiment: 11 calibration standard solutions used in the calculation of the component concentration of the developer using the multivariate analysis method were used as simulated developer samples, and the alkali component concentration (TMAH) was measured for these samples. Concentration), dissolved photoresist concentration, absorbed carbon dioxide concentration and density, and confirmed the correlation between the component concentration and density.

Table 6 below shows the measurement results of the component concentration and density of each sample. Table 6 is a comparison table between the concentration measurement values (wt%) in Table 5 and the density (g / cm ³ ) in Table ³ .

FIG. 5 is a graph showing the carbon dioxide absorption concentration and density of each sample shown in Table 6. FIG. This graph plots the values of each sample with the absorption carbon dioxide concentration (wt%) as the horizontal axis and the density (g / cm ³ ) as the vertical axis. From each of the points drawn, a regression line is obtained by a least square method.

It can be understood from FIG. 5 that although there are various changes in the concentration of the alkali component of the developing solution and the concentration of the dissolved photoresist, there is still a good linear relationship between the concentration of the absorbed carbon dioxide and the density of the developing solution. Based on the results of this experiment, the inventors have discovered that as long as the correspondence relationship (linear relationship) between the concentration of carbon dioxide absorbed by the developer and the density is used, the concentration of carbon dioxide absorbed by the developer can be calculated by measuring the density of the developer .

Therefore, regardless of the alkali component concentration (TMAH concentration) and the dissolution inhibitor concentration, by using this correspondence (linear relationship), the density of the absorbed carbon dioxide of the developing solution can be measured using a density meter.

In the calculation unit 33, the relationship between the density of the developing solution and the absorbed carbon dioxide concentration can be used to easily measure the absorbed carbon dioxide concentration of the developing solution.

[Fifth Embodiment]

FIG. 6 is a schematic diagram for explaining a developing process of the developer management device D according to this embodiment. The developing solution management device D of the present invention is shown together with the developing process equipment A, the replenishing solution storage portion B, the circulation stirring mechanism C, and the like. In addition, the same configurations as those of the first embodiment and the second embodiment may be assigned the same reference numerals, and descriptions thereof may be omitted.

The developer management apparatus D according to the present embodiment includes a measurement unit 1, a control means 21, and a calculation means 37. In this embodiment, unlike the fourth embodiment, the control means 21 and the arithmetic means 37 for performing calculations are configured as separate devices. The measurement unit 1 of this embodiment includes a conductivity meter 11, a first concentration measuring means 12, and a density meter 13B. The computing means 37 calculates the absorbed carbon dioxide concentration of the developing solution from the density of the developing solution measured by the density meter 13B based on the correspondence between the absorbed carbon dioxide concentration and the density of the developing solution.

The control unit 31 calculates the measured conductivity of the conductivity data stored in the data storage unit 23 based on the dissolved photoresist concentration measured by the measurement unit 1 and the absorbed carbon dioxide concentration calculated by the calculation means 37. Dissolves the photoresist concentration and the measured value of the absorbed carbon dioxide concentration to determine the conductivity value in a specific concentration range. The obtained conductivity value is set as a control target value of the developer conductivity.

The other configurations, operations, and the like are the same as those of the fourth embodiment, and are omitted.

As described above, according to the developing solution management device D of this embodiment, no matter what the concentration of the developing solution is to dissolve the photoresist concentration and absorb the carbon dioxide concentration, the active components in the developing solution that are active for the development can be maintained constant. Therefore, a desired development performance can be maintained, and a development process capable of maintaining a desired line width and a residual film thickness of the wiring pattern on the substrate can be achieved.

Next, a modification of the developer management device D of this embodiment will be described.

Although FIGS. 1 to 4 and 6 show the developer management device D in which the measurement unit 1 of the developer management device D and the control means 21 and the arithmetic means 36 and 37 are integrated, the developer management device D of this embodiment is not Limited to this. The measurement unit 1 may be configured separately.

The measurement unit 1 has an optimal setting method according to the measurement principle adopted, so it may be provided, for example, to connect the measurement unit 1 to the developer line 80 inline, or to connect the measurement probe A developing probe is immersed in the developer storage tank 61. Each of the conductivity meters 11, the first concentration measuring means 12, the first characteristic value measuring means 12A, the second concentration measuring means 13, the second characteristic value measuring means 13A, and the density meter 13B may be individually provided. The developer management device D of the present embodiment can be realized as long as it is configured so that each measurement means can communicate with the control means 21 and the calculation means 36 and 37 to send and receive measurement data.

In accordance with the measurement principle adopted by each measurement method, if it is necessary to add a test drug, each measurement method may also have a pipe for adding a test drug. If there is a waste liquid, each measurement method may also be provided for waste liquid. Of the pipeline. Even when the measurement means are not connected in series, the developer management device D of this embodiment can be implemented.

Although FIGS. 1 to 4 and 6 depict the method in which the control valves 41 to 43 provided in the pipeline for supplying the replenishing liquid to the developer are made as internal parts of the developer management device D, the developer management device D and Although the replenishing liquid pipes 81 and 82 and the pure water pipe 83 are connected, the developer management device D of this embodiment is not limited to this. The developer management device may not include control valves 41 to 43 in the form of internal parts, and may not be connected to the lines 81 to 83 for replenishing the developer to the developer.

The control means 21 of the developer management device D of this embodiment and the control valves 41 to 43 provided in the pipeline for replenishing the liquid need only be configured so that the control valves 41 to 43 receive the signals from the developer management device D. The control signals sent by the control means 21 may be controlled in a manner in which the control methods can communicate with each other. Even if the control valve is not configured as an internal part of the developer management device D, the developer management device D of this embodiment can be implemented.

The developer management device of the present invention has conductivity data regardless of whether the above-mentioned various modifications are allowed or not. The conductivity number is specified for each concentration based on the concentration of the dissolved photoresist in the developer and the concentration of absorbed carbon dioxide. The area has the conductivity value of the aforementioned developer solution, which has been confirmed to have predetermined development performance in advance; and the conductivity of the specific concentration area is determined by the measurement value of the dissolved photoresist concentration of the developer solution and the measurement value of the absorbed carbon dioxide concentration. The conductivity value of the data is used as the control target value, and the replenisher liquid supplied to the developer solution is transported so that the conductivity of the developer solution becomes the control target value.

As described above, according to the developing solution management method and the developing solution management device of the present invention, regardless of the concentration of the dissolved photoresist and the concentration of carbon dioxide absorbed by the developing solution, the active components in the developing solution that are active for the development can be maintained constant. Therefore, a desired development performance can be maintained, and a development process capable of maintaining a desired line width and a residual film thickness of the wiring pattern on the substrate can be realized.

In a preferred aspect of the developer management device, since the dissolved photoresist concentration and carbon dioxide absorption concentration are calculated by a multivariate analysis method, the dissolved photoresist concentration and carbon dioxide absorption concentration can be obtained with good accuracy. The target conductivity value can be obtained from the conductivity data based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration.

Furthermore, in a preferred aspect of the developing solution management device, the absorption of the developing solution is calculated from the density of the developing solution measured by the density meter according to the correspondence between the concentration of the absorbed carbon dioxide and the density of the developing solution. CO2 concentration. This makes it easier to obtain the concentration of carbon dioxide absorbed by the developer. Based on the absorbed carbon dioxide concentration and the dissolved photoresist concentration obtained separately, the target conductivity value can be obtained from the conductivity data.

Claims (11)

    A developer management device includes control means and alarm means. The control means includes: a data memory section that stores conductivity data, and the conductivity data is based on the dissolving photoresist in alkaline developer that is used repeatedly. Each concentration region specified by the concentration and the concentration of absorbed carbon dioxide as indicators has a conductivity value of the aforementioned developing solution which has been previously confirmed to be a predetermined developing performance; and a control unit for dissolving the photoresist concentration by the aforementioned developing solution. The measured value of the measured value and the measured value of the concentration of absorbed carbon dioxide are stored in the aforementioned data storage section as the control target value, and the conductivity value of the specific concentration region is set in such a way that the conductivity of the developer solution becomes the control target value. A control signal is sent from a control valve of a pipeline for supplying the replenishing solution to the developer; the alarm means is that the conductivity of the developer, the concentration of dissolved photoresist, and the concentration of absorbed carbon dioxide deviate from the set value. When the management scope of the alarm is issued.         For example, the developer management device of claim 1 is provided with an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights up or blinks, a display device that displays a warning, and a switching contact. At least one of the opened and closed relay terminals is used as the aforementioned alarm means.         A developer management device includes control means. The control means includes: a data storage unit that stores conductivity data. The conductivity data is based on the concentration and absorption of the dissolved photoresist in a alkaline developer that is used repeatedly. Each concentration region specified by the carbon dioxide concentration as an indicator has a conductivity value of the aforementioned developing solution which has been previously confirmed to be a predetermined developing performance; and a control unit for measuring the measured value of the concentration of the photoresist dissolved by the aforementioned developing solution and The measured value of the concentration of carbon dioxide is absorbed, and the conductivity value of the specific concentration region stored in the data memory section is used as a control target value, so that the conductivity of the developer is set to the control target value so that The control valve of the pipeline for the replenishing solution of the developer sends a control signal; each of the conductivity, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide is provided with the conductivity of the developer, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide. An alarm means that emits an alarm when it deviates from the set management range.         For example, the developer management device of claim 3 is provided with an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights up or blinks, a display device that displays a warning, and a switching contact. At least one of the opened and closed relay terminals is used as the aforementioned alarm means.         The developer management device according to any one of claims 1 to 4, further comprising a plurality of measuring devices for measuring the characteristics of the developer containing the developer in relation to the dissolved photoresist concentration of the developer. The characteristic value of the developer and the characteristic value of the developer related to the absorbed carbon dioxide concentration of the developer; the control means further includes: an arithmetic unit, which is measured from the plurality of measuring devices. For the plurality of characteristic values of the developer, the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer are calculated by a multivariate analysis method.         The developer management device according to any one of claims 1 to 4, further comprising: a plurality of measuring devices for measuring a characteristic value of the developer containing the developer in relation to the dissolved photoresist concentration of the developer, and A plurality of characteristic values of the developing solution that are related to a characteristic value of the developing solution that absorbs carbon dioxide; and a calculation means based on the plurality of developing solutions measured by the plurality of measuring devices The characteristic value was calculated using a multivariate analysis method to measure the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration.         For example, the developer management device according to any one of claims 1 to 4, further comprising a density meter, and the aforementioned control means further includes: an arithmetic unit, based on the correspondence between the absorbed carbon dioxide concentration and the density of the developer, borrowing From the density value of the developing solution measured by the densitometer, the value of the absorbed carbon dioxide concentration of the developing solution is calculated.         The developer management device according to any one of claims 1 to 4, further comprising: a density meter; and a calculation means based on a correspondence relationship between the concentration of the absorbed carbon dioxide and the density of the developer, and by using the density The measured value of the density of the developer was used to calculate the carbon dioxide absorption value of the developer.         A developer management device includes a control means and an alarm means. The control means includes a data memory unit that stores alkali component concentration data, and the alkali component concentration data is based on dissolution with a developer that is alkaline after repeated use. The concentration of the photoresist has a specific absorbance and carbon dioxide absorption concentration as indicators, and each concentration region has an alkali component concentration value of the aforementioned developing solution which has been confirmed to be a predetermined developing performance in advance; and a control unit to pass the aforementioned The measured value of absorbance and carbon dioxide concentration of the developing solution, and the alkali component concentration value stored in the data memory section in a specific concentration region is used as a control target value, so that the alkali component concentration of the developing solution will become the control target value. A control signal is provided to a control valve provided in a pipeline for supplying a replenishing solution to the developing solution. The alarm means deviates from the setting by at least any one of the concentration of the alkali component, the absorbance, and the concentration of absorbed carbon dioxide of the developing solution. When the management scope of the alarm is issued.         A developer management device includes control means. The control means includes a data storage unit that stores alkali component concentration data. The alkali component concentration data is a photoresist dissolving agent based on a developer that is alkaline with repeated use. The concentration has a specific absorbance and carbon dioxide absorption concentration as indicators, each concentration region being specific, having an alkali component concentration value of the aforementioned developing solution which has been confirmed to be a predetermined developing performance in advance; and a control unit for using the aforementioned developing solution's The measured values of absorbance and absorption of carbon dioxide concentration, and the specific alkali concentration value stored in the data memory section as a control target value are set so that the basic component concentration of the developing solution will become the control target value. A control signal is sent from a control valve of a pipeline for supplying a replenishing solution to the developer; each of the alkali component concentration, absorbance, and carbon dioxide absorption concentration is provided when the alkali component concentration, absorbance, and carbon dioxide absorption concentration of the developer deviates from the An alarm means that generates an alarm when the management range is set.         If the developer management device of item 9 or 10 is requested, it is provided with an external output signal terminal that emits an alarm signal, an alarm device that emits an alarm sound, a warning lamp that lights up or flashes, a display device that displays a warning, and a switching interface. At least one of the opened and closed relay terminals of the dots serves as the aforementioned alarm means.