JP6721157B2 - Method and apparatus for measuring component concentration of developer, and method and apparatus for managing developer - Google Patents

Description

Component concentration measuring method and component concentration measuring device of a developer exhibiting alkalinity, which is repeatedly used for developing a photoresist film in a developing process of a circuit board in a semiconductor or a liquid crystal panel, and a developer controlling method and a developer. Management device.

In the development process of photolithography that realizes fine wiring processing in semiconductors, liquid crystal panels, etc., as a chemical solution that dissolves the photoresist formed on the substrate, a developing solution showing alkalinity (hereinafter referred to as “alkaline developing solution”). .) is used.

In the manufacturing process of semiconductors and liquid crystal panel substrates, in recent years, wafers and glass substrates have been increased in size, and wiring processing has been miniaturized and highly integrated. Under such circumstances, it is necessary to measure the concentration of the main components of the alkaline developer with even higher accuracy and maintain the developer in order to realize finer wiring processing and higher integration of large substrates. Is becoming.

As described in Patent Document 1, the conventional measurement of the component concentration of the alkaline developer is good between the concentration of the alkaline component of the alkaline developer (hereinafter, referred to as “alkali component concentration”) and the conductivity. And a good linear relationship between the concentration of the photoresist dissolved in the alkaline developer (hereinafter referred to as “dissolved photoresist concentration”) and the absorbance are utilized. It was a thing.

However, the alkaline developer absorbs carbon dioxide in the air to form a carbonate, which easily deteriorates. Further, the alkaline developer produces a photoresist salt by dissolution of the photoresist, and the alkaline component effective for the development process is consumed. Therefore, the alkaline developer used repeatedly is a multi-component system containing not only an alkaline component but also photoresist and carbon dioxide. Then, each of these components affects development performance with different contributions. Therefore, in order to maintain and manage the developing performance of the developing solution with high accuracy, it is necessary to manage the developing solution in consideration of the effects of these components on the developing performance.

In order to solve such a problem, in Patent Document 2, the ultrasonic wave propagation speed, conductivity and absorbance of a developing solution are measured, and the ultrasonic wave propagation speed and conductivity at alkali concentration, carbonate concentration and dissolved resin concentration are measured. And the absorbance of the developer based on the relationship (matrix) created in advance to detect the alkali concentration, carbonate concentration and dissolved resin concentration, the alkali concentration, carbonate concentration and dissolved resin concentration of the measured developer, and The supply of the developing solution stock solution is controlled on the basis of the previously created relationship between the alkali concentration, the carbonate concentration and the dissolved resin concentration that can exert the dissolving ability such that the CD value (line width) becomes a constant value. A developing solution preparation device for adjusting the alkali concentration is disclosed.

Further, in Patent Document 3, a carbonate-based salt concentration measuring device that measures the refractive index, conductivity, and absorbance of the developer and obtains the carbonate-based salt concentration in the developer from these measured values, and this carbonate There is disclosed an alkali developer management system including a system salt concentration measuring device and a control unit for controlling the concentration of carbonate salts in the developer.

Japanese Patent No. 2561578 JP, 2008-283162, A JP, 2011-128455, A

However, the ultrasonic wave propagation velocity value and the refractive index value of the alkaline developing solution are characteristic values indicating the properties of the entire alkaline developing solution which is a multi-component system. The characteristic value indicating the property of the whole liquid is not generally correlated only with the concentration of the specific component contained in the liquid. The characteristic value indicating the property of the whole liquid usually has a correlation with each of the concentrations of various components contained in the liquid. Therefore, when the component concentration of the developing solution is calculated from the measured value of the characteristic value indicating the property of the whole solution, it is considered that a certain characteristic value correlates only with a certain specific component concentration (for example, has a linear relationship). There is a problem that the concentration of the specific component cannot be calculated with sufficient accuracy if the effect of the component on the characteristic value is ignored.

On the other hand, when calculating the concentration of each component from the measured value of the characteristic value of the developing solution assuming that the characteristic value of the developing solution is a function of the concentration of various components contained in the developing solution, after measuring a plurality of characteristic values, It is necessary to adopt an appropriate calculation method for calculating the concentration of each component from the measured values of these characteristic values. However, it is very difficult to properly select the characteristic value to be measured and to find an appropriate calculation method that can accurately calculate the concentration of each component from the measured value of the characteristic value. Therefore, there is a problem that the concentration of each component cannot be calculated with sufficient accuracy unless the measured characteristic value and the calculation method are appropriate.

Moreover, in multi-component liquids, the concentration of one component is generally not independent of the concentration of another component. In a multi-component liquid, there is a mutual relationship that when the concentration of one component changes, the concentration of another component also changes at the same time. This makes highly accurate component concentration calculation and highly accurate developer management difficult.

In addition, regarding the concentration of carbon dioxide absorbed in the developing solution (hereinafter referred to as "absorbed carbon dioxide concentration"), suitable characteristic values of the developing solution showing a good correlation with this are not known, and It was difficult to accurately measure the absorbed carbon dioxide concentration.

Further, in Patent Document 2, in order to detect the component concentration of the developing solution, it is necessary to previously acquire a mutual relationship (matrix) between the component concentration of the developing solution and a characteristic value such as an ultrasonic wave propagation velocity. .. However, in this case, if the mutual relationship (matrix) is rough, the component concentration cannot be calculated accurately. In order to calculate the component concentration with high accuracy, the relationship (matrix) between the characteristic values of the developer used for the calculation and the component concentration must be sufficiently dense. Therefore, as the calculation accuracy of the component concentration is increased, it is necessary to prepare more samples in advance and measure the correlation between the component concentration and the characteristic value of the developing solution. Preparing such a dense mutual relationship (matrix) in advance is an enormous amount of work, and has been a problem in realizing highly accurate measurement of the component concentration of the developer.

The present invention has been made to solve the above problems. INDUSTRIAL APPLICABILITY The present invention can accurately measure the component concentration of the developer from the characteristic value of the developer which is a multi-component system, and analyzes the component concentration of the developer without requiring preparation of a huge number of samples or preliminary measurement. An object of the present invention is to provide a method and an apparatus for measuring the component concentration of a developing solution, and a method and an apparatus for managing a developing solution capable of controlling the component concentration of the developing solution more precisely.

In order to achieve the above-mentioned object, the present invention comprises a step of calculating a component concentration of a developer by a multivariate analysis method (for example, a multiple regression analysis method), and a calculation section. That is, the present invention provides the following component concentration measuring method, component concentration measuring device, developing solution management method, and developing solution management device.

(1) A step of measuring a plurality of characteristic values of a developer, which is used repeatedly and has a correlation with the component concentration of the developer exhibiting alkalinity, and a multivariate analysis method based on the plurality of measured characteristic values, And a step of calculating the component concentration of the developer, the method for measuring the component concentration of the developer.

(2) A multivariate based on a plurality of characteristic values measured repeatedly by a measuring unit that measures a plurality of characteristic values of the developing solution that are correlated with the component concentration of the alkaline developing solution. An apparatus for measuring the component concentration of a developer, comprising: an arithmetic unit that calculates the component concentration of the developer by an analysis method.

(3) A step of measuring a plurality of characteristic values of the developer, which are used repeatedly and correlated with the component concentration of the developer exhibiting alkalinity, and a multivariate analysis method based on the measured plurality of characteristic values. And the measured value of the management target item selected from the plurality of characteristic values of the developer measured in the measuring step and the component concentration of the developer calculated in the calculating step. Replenishing the developing solution with a replenisher based on the value.

(4) A multivariate based on a plurality of characteristic values which are repeatedly used and which measure a plurality of characteristic values of the developing solution having a correlation with the component concentration of the developing solution exhibiting alkalinity, and a plurality of characteristic values measured by the measuring section. Management target item selected from the calculation unit that calculates the component concentration of the developer by the analysis method, the plurality of characteristic values of the developer measured by the measurement unit, and the component concentration of the developer calculated by the calculation unit A developing solution management device, comprising: a control section for issuing a control signal to a control valve provided in a flow path for feeding a replenisher solution to be replenished with the developing solution based on the measured value or calculated value of

(5) First measuring means for measuring a characteristic value of the developing solution having a correlation with the concentration of at least an alkali component of the developing solution components, and a photo dissolved in at least the developing solution of the developing solution components. The developing solution management device according to (4), further comprising: second measuring means for measuring a characteristic value of the developing solution having a correlation with the concentration of the resist.

(6) The calculation unit includes a calculation block for calculating the concentration of the alkaline component of the developing solution and the concentration of the photoresist, and the control unit controls the concentration of the alkaline component calculated by the calculation block to be a predetermined control value. A control block for issuing a control signal to the control valve, and a control block for issuing a control signal to the control valve so that the concentration of the photoresist calculated by the calculation block is equal to or lower than a predetermined control value. Developer management device.

(7) The measuring unit further comprises third measuring means for measuring a characteristic value of the developing solution which is correlated with at least the concentration of carbon dioxide absorbed in the developing solution among the components of the developing solution. Developer management device.

(8) The calculation unit includes a calculation block for calculating the concentration of carbon dioxide in the developing solution, and the control unit controls the characteristic value of the developing solution measured by the first measuring unit to be a predetermined control value. Calculated by a control block that issues a control signal to the control valve, a control block that issues a control signal to the control valve so that the characteristic value of the developing solution measured by the second measuring means falls within a predetermined control region, and an arithmetic block The developing solution management apparatus according to (7), including a control block that issues a control signal to the control valve so that the concentration of carbon dioxide to be generated becomes equal to or lower than a predetermined management value.

(9) The calculation unit includes a calculation block that calculates the concentration of the alkaline component and the concentration of carbon dioxide of the developer, and the control unit sets the concentration of the alkaline component calculated by the calculation block to a predetermined control value. , A control block for issuing a control signal to the control valve, a control block for issuing a control signal to the control valve so that the characteristic value of the developing solution measured by the second measuring means falls within a predetermined control region, and an operation block. The developing solution management apparatus according to (7), including a control block that issues a control signal to the control valve so that the calculated carbon dioxide concentration is equal to or lower than a predetermined management value.

(10) The calculation unit includes a calculation block for calculating the concentration of the alkaline component of the developer, the concentration of the photoresist, and the concentration of carbon dioxide, and the control unit controls the concentration of the alkaline component calculated by the calculation block to a predetermined value. Control block that issues a control signal to the control valve, and a control block that issues a control signal to the control valve so that the concentration of the photoresist calculated by the computation block is below a predetermined control value. The developing solution management apparatus according to (7), including a control block that issues a control signal to the control valve so that the concentration of carbon dioxide calculated by the block becomes equal to or less than a predetermined management value.

According to the present invention, since the component concentration of the alkaline developer which is a multi-component system is calculated by the calculating means using the multivariate analysis method (for example, the multiple regression analysis method), the characteristic value to be measured and the specific value Compared with the conventional method that calculates the component concentration assuming that the component concentration has a predetermined correlation (for example, a linear relationship), the component concentration of the developer can be accurately determined even from the characteristic values affected by the plurality of developer components. It is possible to calculate. In particular, according to the present invention, it is possible to measure the absorbed carbon dioxide concentration of the developer, which has been difficult to measure conventionally. Further, compared to a method of preparing a correlation (matrix) between a plurality of measurement characteristic values and a plurality of component concentrations in advance and using it for the calculation of the component concentration, the present invention prepares a huge amount of samples and conducts a preliminary measurement. There is no need to carry it out.

According to the present invention, the concentration of each component of the alkaline developer which is a multi-component system can be measured more accurately than before, so that the concentration of alkaline components, the concentration of dissolved photoresist and the concentration of absorbed carbon dioxide are more accurate than those of conventional ones. It is possible to control it well. Further, according to the present invention, it is also possible to select management for controlling the conductivity value of the developing solution to be constant and management for controlling the absorbance value of the developing solution to be equal to or less than a certain absorbance value.

FIG. 6 is a flow chart of a component concentration measuring method showing a signal flow when measuring the component concentrations of two components from two characteristic values. It is a flowchart of the component concentration measuring method which shows the flow of a signal when measuring the component concentration of three or more components from three or more characteristic values. It is a flowchart of the component concentration measuring method which shows the flow of a signal when the calculation method different from a multivariate analysis method is included. FIG. 3 is a schematic diagram of a component concentration measuring device that measures two components of a developer. It is a schematic diagram of a component concentration measuring device for measuring three components of a developing solution. It is a schematic diagram of the component concentration measuring apparatus which has a calculation block by a calculation method different from the multivariate analysis method in a calculation part. It is a schematic diagram of a component concentration measuring device in the case of performing in-line measurement, in which the measurement unit and the calculation unit are separate bodies. It is a schematic diagram of a component concentration measuring device in the case where the measuring means includes a main body and a probe unit. It is a schematic diagram of a component concentration measuring device provided with measuring means in parallel. It is a schematic diagram of a component concentration measuring device in the case of including a measuring device that requires addition of a drug. It is a schematic diagram which applied the component concentration measuring apparatus to the developing solution management apparatus. It is a schematic diagram for showing an application example of a component concentration measuring device. It is a flowchart of the developing solution management method which manages two components of a developing solution by component concentration. FIG. 6 is a flow chart of a developing solution management method in which one of two components of the developing solution is managed by a component concentration and the other is managed by a characteristic value. It is a flowchart of the developing solution management method which manages three components of a developing solution by component density. FIG. 6 is a flow chart of a developing solution management method in which one of three components of the developing solution is managed by a characteristic value and the other two are managed by a component concentration. FIG. 6 is a flow chart of a developing solution management method in which two out of three components of the developing solution are managed by a characteristic value and the other one is managed by a component concentration. It is a schematic diagram of the developing process for explaining the developing solution management apparatus of the present invention. It is a schematic diagram of the developing solution management apparatus which controls the control valve outside the apparatus. It is a schematic diagram of the developing solution management apparatus provided with the calculation control part which has both a calculation function and a control function. It is a schematic diagram of the developing solution management apparatus which manages two components of a developing solution. FIG. 3 is a schematic diagram of a developing solution management device that manages two components of a developing solution based on the component concentrations. FIG. 3 is a schematic diagram of a developing solution management device that manages two of the three components of the developing solution by characteristic values and the other one by component concentration. FIG. 3 is a schematic diagram of a developing solution management device that manages one of the three components of the developing solution by a characteristic value and the other two by the component concentration. It is a schematic diagram of the developing solution management apparatus which manages three components of a developing solution by a component concentration.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as appropriate. However, the shapes, sizes, dimensional ratios, relative arrangements, etc. of the devices and the like described in these embodiments are only those shown in the scope of the present invention unless otherwise specified. It is not limited. It is merely shown schematically as an example of explanation.

Further, in the following description, as a specific example of the developer, a 2.38% tetramethylammonium hydroxide aqueous solution (hereinafter, tetramethylammonium hydroxide is referred to as TMAH) that is mainly used in the manufacturing process of semiconductors and liquid crystal panel substrates. Will be described as appropriate. However, the developing solution to which the present invention is applied is not limited to this. As an example of other developer to which the component concentration measuring device of the developer of the present invention and the developer managing device can be applied, potassium hydroxide, sodium hydroxide, sodium phosphate, an aqueous solution of an inorganic compound such as sodium silicate, An aqueous solution of an organic compound such as trimethylmonoethanol ammonium hydroxide (choline) can be mentioned.

Further, the multivariate analysis method (for example, multiple regression analysis method) does not depend on the unit concentration of the component concentration when calculating the component concentration, but in the following description, the alkali component concentration, the dissolved photoresist, Concentrations of components such as concentration and absorbed carbon dioxide concentration are concentrations by weight percentage concentration (wt%). "Dissolved photoresist concentration" means the concentration when the dissolved photoresist is converted as the amount of photoresist, and "absorbed carbon dioxide concentration" is when the absorbed carbon dioxide is converted as the amount of carbon dioxide. It means the concentration of.

In the developing process, the developing solution dissolves an unnecessary portion of the photoresist film after the exposure process to perform the developing. The photoresist dissolved in the developing solution forms a photoresist salt with the alkaline component of the developing solution. For this reason, unless the developer is properly managed, the alkaline component having the developing activity is consumed and deteriorates as the developing process progresses, and the developing performance deteriorates. At the same time, the dissolved photoresist accumulates in the developer as a photoresist salt with an alkaline component.

The photoresist dissolved in the developing solution exhibits a surface-active effect in the developing solution. For this reason, the photoresist dissolved in the developing solution enhances the wettability of the photoresist film to be subjected to the developing treatment with respect to the developing solution, and improves the compatibility between the developing solution and the photoresist film. Therefore, with a developer containing an appropriate amount of photoresist, the developer is well distributed in the fine recesses of the photoresist film, and the photoresist film having fine irregularities can be well developed.

Further, in recent development processing, a large amount of developing solution has been repeatedly used with the increase in size of the substrate, so that the developing solution is increasingly exposed to air. However, the alkaline developer absorbs carbon dioxide in the air when exposed to the air. The absorbed carbon dioxide forms a carbonate with the alkaline component of the developer. For this reason, unless the developer is properly managed, the developer is consumed by the carbon dioxide in which the alkaline component having the developing activity is absorbed and decreases. At the same time, the absorbed carbon dioxide accumulates in the developer as a carbonate with the alkaline component.

The carbonate in the developer has a developing action because it exhibits alkalinity in the developer. For example, in the case of a 2.38% TMAH aqueous solution, if carbon dioxide in the developing solution is about 0.4 wt% or less, development is possible.

Thus, unlike the conventional recognition that the photoresist dissolved in the developing solution and the absorbed carbon dioxide are unnecessary for the developing process, they actually contribute to the developing performance of the developing solution. Therefore, instead of managing the developing solution to completely eliminate dissolved photoresist and absorbed carbon dioxide, a developing solution that maintains and manages these at an optimum concentration while allowing them to be dissolved slightly in the developing solution Needs management.

Further, a part of the photoresist salt or carbonate generated in the developer is dissociated to generate various free ions such as photoresist ion, carbonate ion, hydrogen carbonate ion. Then, these free ions influence the conductivity of the developer with various contribution rates.

In the conventional alkaline developer component concentration analysis, the alkaline component concentration of the developer has a good linear relationship with the conductivity value of the developer, and the dissolved photoresist concentration of the developer is good with the absorbance value of the developer. It has a linear relationship (hereinafter referred to as "conventional method"). The accuracy of the developer control required in the conventional developing process was sufficiently realized by this analysis method because the absorption amount of carbon dioxide was not yet large.

The conductivity value of the developer is a physical property value that depends on the number of charged particles such as ions contained in the developer and the amount of charge thereof. As described above, in the developing solution, not only the alkaline component but also various free ions derived from the photoresist dissolved in the developing solution and the carbon dioxide absorbed in the developing solution are present. Therefore, in order to improve the analysis accuracy of the component concentration, it was necessary to use a calculation method that also takes into consideration the influence of these free ions on the conductivity value of the developer.

The absorbance value of a developing solution is a physical property value having a linear relationship with the concentration of a specific component that selectively absorbs light of the measurement wavelength (Lambert-Beer's law). However, in a multi-component system, although the degree varies depending on the measurement wavelength, the absorption spectrum of the target component usually overlaps with the absorption spectrum of the other component. Therefore, in order to improve the analysis accuracy of the component concentration, it was necessary to use a calculation method that takes into consideration not only the photoresist dissolved in the developer but also the influence of other components on the absorbance value of the developer. ..

With respect to these points, the inventor, as a result of continuing diligent research, has found that when a multivariate analysis method (for example, multiple regression analysis method) is used as a calculation method, each component of the developer is more accurately than when the conventional method is used. It has been found that the concentration of carbon dioxide can be calculated, and the absorbed carbon dioxide concentration, which was difficult in the past, can be measured. Further, the inventor can maintain and manage the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer in a good state by using the component concentration of the developer calculated by the multivariate analysis method (for example, multiple regression analysis method). Found.

The inventor prepared a TMAH aqueous solution in which the concentration of the alkaline component, the concentration of the dissolved photoresist, and the absorbed carbon dioxide concentration were variously changed as a simulated developer sample, assuming the case of controlling the 2.38% TMAH aqueous solution. The inventor conducted an experiment for determining the component concentration of each of the simulated developer samples by a multiple regression analysis method from various characteristic values measured. Hereinafter, a general calculation method by the multiple regression analysis method will be described, and then a calculation method of the component concentration of the developer using the multiple regression analysis method will be described based on an experiment conducted by the inventor.

Multiple regression analysis consists of two steps, calibration and prediction. It is assumed that m calibration standard solutions are prepared in the multiple regression analysis of the n-component system. The concentration of the j-th component existing in the i-th solution is represented as Cij. Here, i=1 to m and j=1 to n. For each of the m standard solutions, p characteristic values (for example, physical properties such as absorbance and conductivity at a certain wavelength) Aik (k=1 to p) are measured. The concentration data and the characteristic data can be collectively expressed in the form of a matrix (C, A).

A matrix that relates these matrices is called a calibration matrix, and is represented by the symbol S (Skj; k=1 to p, j=1 to n) here.

It is possible to calculate S from a known C and A (the content of A is not limited to the same measurement value but also different measurement values may be mixed. For example, conductivity, absorbance, and density) by matrix calculation. It is a calibration stage. At this time, p>=n and m>=np must be satisfied. Since each element of S is an unknown number, it is desirable that m>np. In that case, the least squares operation is performed as follows.

Here, the superscript T means a transposed matrix, and the superscript -1 means an inverse matrix.

P characteristic values were measured for a sample solution of unknown concentration, and Au(Auk; k=1 to p
), it is possible to obtain the concentration Cu (Cuj; j=1 to n) to be obtained by multiplying it by S.

This is the prediction stage.

The inventor considers the used alkaline developer (2.38% TMAH aqueous solution) as a multi-component system (n=3) consisting of three components of an alkali component, a dissolved photoresist, and absorbed carbon dioxide, and considers the developer. From the three physical property values (p=3), that is, the conductivity value of the developer, the absorbance value at a specific wavelength, and the density value, an experiment for calculating the concentration of each component by the above multiple regression analysis method was performed. It was The inventor prepared eleven calibration standard solutions in which the concentration of alkali components (TMAH concentration), the concentration of dissolved photoresist, and the concentration of absorbed carbon dioxide were variously changed using a 2.38% TMAH aqueous solution as a basic composition of the developer. (When m=11, p>=n and m>np are satisfied).

In the experiment, the conductivity value, the absorbance value at the wavelength λ=560 nm, and the density value of the 11 calibration standard solutions were measured as the characteristic values of the developing solution, and the concentration of each component was analyzed by multiple linear regression analysis (Multiple Linear Regression- Inverse Least Squares; MLR-ILS).

The measurement was performed by adjusting the temperature of the calibration standard solution to 25.0°C. To adjust the temperature, immerse the bottle containing the calibration standard solution in a constant temperature water bath whose temperature is controlled at around 25°C for a long time, sample it from here, and bring it back to 25.0°C again with a temperature controller immediately before measurement. , Is the method. As the conductivity meter, we used a self-made conductivity meter. It was measured using an in-house conductivity flow cell that had been subjected to platinum black treatment. The cell constant of the conductivity flow cell, which is separately confirmed by the calibration work, is input to the conductivity meter. The absorptiometer was also manufactured in-house. It is an absorptiometer including a light source unit having a wavelength λ=560 nm, a photometric unit, and a glass flow cell. For the density measurement, a density meter adopting a natural vibration method in which the density is calculated from the natural frequency measured by exciting a U-shaped flow cell is used. The units of the measured conductivity value, absorbance value and density value are mS/cm and Abs. (Absorbance), g/cm ³ .

For the calculation, one of the 11 calibration standard solutions is regarded as an unknown sample, the calibration matrix is obtained with the remaining 10 standards, and the concentration of the assumed unknown sample is calculated to obtain a known value (by another accurate analysis method). This is based on a method (single-out crossing confirmation method; Leave-One-Out method) of comparing the measured concentration value and the weight adjustment value.

The results of the MLR-ILS calculation are shown in Table 1.

In the MLR-ILS calculation, in view of the fact that the TMAH aqueous solution is strongly alkaline and easily absorbs carbon dioxide and deteriorates, the concentration matrix used for the calculation includes a titration analysis method capable of accurately analyzing the concentration of alkali components and the concentration of absorbed carbon dioxide. The value obtained by separately measuring the calibration standard solution was used. However, regarding the concentration of the dissolved photoresist, the weight adjusted value was used.

The titration is a neutralization titration using hydrochloric acid as a titration reagent. As a titrator, an automatic titrator GT-200 manufactured by Mitsubishi Chemical Analytech Co. was used.

The concentration matrix is shown in Table 2 below.

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

The calibration matrix is shown in Table 4.

Table 5 shows a comparison between the measured concentration 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 TMAH concentration and the absorbed carbon dioxide concentration measured by the titration analysis, and the dissolution obtained from the adjusted weight. The values are very close to the photoresist concentration.

In this way, the conductivity of the alkaline developer, the absorbance at a specific wavelength, and the density are measured, and by using a multivariate analysis method (for example, multiple regression analysis method), the alkaline component concentration of the developer, the dissolution photo It is understood that the resist concentration and the absorbed carbon dioxide concentration can be measured.

The multivariate analysis method (for example, the multiple regression analysis method) is effective in calculating and obtaining the concentrations of a plurality of components. It is possible to measure a plurality of characteristic values a, b, c,... Of the developer and obtain the component concentrations A, B, C,... From the measured values by a multivariate analysis method (eg, multiple regression analysis method). it can. At this time, for the component concentration to be obtained, at least one characteristic value having a correlation with this component concentration must be measured and used in the calculation.

Here, the characteristic value of the developing solution “correlated” with the component concentration means that the characteristic value is related to the component concentration, and that the characteristic value is changed according to the change of the component concentration. Say. For example, the characteristic value a of the developer having a correlation with at least the component concentration A of the component concentration of the developer is one of the variables when the characteristic value a is obtained by a function having the component concentration as a variable. It is meant to include the concentration A. Although the characteristic value a may be a function of only the component concentration A, normally, when the characteristic value a is a multivariable function having the component concentrations B, C, etc. as variables, the multivariate analysis is performed. The significance of using the method (for example, multiple regression analysis method) is great.

The component concentration is a scale showing the relative amount of the component with respect to the whole. The component concentration of a mixed solution in which the components increase and decrease over time, such as a repeatedly used developer, is not determined by the component alone, but is usually a function of the concentrations of other components. Therefore, it is often difficult to display the relationship between the characteristic value of the developer and the component concentration in a planar graph. In such a case, the component concentration cannot be calculated from the characteristic value of the developing solution by a calculation method using a calibration curve or the like.

However, according to the multivariate analysis method (for example, multiple regression analysis method), if one set of measured values of a plurality of characteristic values correlated with the component concentration to be calculated is prepared, it is used for calculation to calculate the component concentration. Is calculated. Even if it is difficult to measure the component concentration at first glance with the conventional knowledge, the remarkable effect that the component concentration can be measured by measuring the characteristic value is obtained by the multivariate analysis method (for example, multiple regression analysis method). It can be obtained by measurement.

As described above, according to the calculation method of the present invention, the alkaline component concentration of the developing solution, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration, the characteristic value of the developing solution (for example, conductivity, absorbance at a specific wavelength, and , Density) can be calculated based on the measured values. According to the calculation method of the present invention, it is possible to calculate the concentration of each component with higher accuracy than in the conventional method.

Further, since the multivariate analysis method (for example, multiple regression analysis method) is used in the present invention, the characteristics of the developer which are not linearly related to the specific component concentration of the developer are used in the calculation for calculating the component concentration of the developer. Values can also be adopted.

Further, according to the present invention, preparation and preliminary measurement of a very large number of samples, which are required in the invention of Patent Document 2, for enabling highly accurate measurement are not necessary. (As in the experimental example described above, if the number of components is n=3, the number of characteristic values to be measured p=3, and the number of samples p satisfying m>=np (for example, p=11 samples) is set. It is sufficient to prepare and measure it. If the number of components n=2, the number of samples may be smaller.)
Furthermore, since the present invention uses a multivariate analysis method (for example, a multiple regression analysis method), it is possible to accurately calculate the absorbed carbon dioxide concentration of the developer, which has been difficult to measure conventionally.

Next, specific examples will be described with reference to the drawings. In the following examples, the characteristic values a, b, c,... And the component concentrations A, B, C,. For a more specific understanding, the characteristic values a, b, c,... Are the conductivity, the absorbance at a specific wavelength (for example, λ=560 nm), the density,. ,... can be reread as the alkali component concentration, the dissolved photoresist concentration, the absorbed carbon dioxide concentration,.

However, the characteristic values a, b, and c are defined as the conductivity, the absorbance at a specific wavelength (for example, λ=560 nm), the density, and the like. This is merely an example of an optimum combination of characteristic values when calculating the density and the like, and the present invention is not limited to this. Various combinations of the characteristic values a, b, c,... Can be selected according to the component concentrations A, B, C,. The characteristic values that can be adopted include, for example, conductivity of the developing solution, absorbance, ultrasonic wave propagation velocity, refractive index, density, titration end point, pH and the like. Since the developer may contain various additives, the component concentration may include the additive concentration in addition to the above three components.

When the developer is controlled by measuring the concentration of alkali components, the concentration of dissolved photoresist, and the concentration of absorbed carbon dioxide in the developer, the combination of conductivity, absorbance at a specific wavelength, and density is preferable as the characteristic value. The specific wavelength for measuring the absorbance is preferably a specific wavelength in the visible region, more preferably in the wavelength region of 360 to 600 nm, further preferably λ=480 nm or 560 nm. When the absorbed carbon dioxide concentration of the developer is relatively low and its change with time is gradual, the conductivity of the developer has a relatively good linear relationship with the concentration of the alkali component, and the developer has a specific wavelength (for example, λ=560 nm). This is because the absorbance in () has a relatively good linear relationship with the dissolved photoresist concentration. In addition, a combination of electrical conductivity, absorbance at a specific wavelength, and ultrasonic wave propagation velocity, and a combination of electrical conductivity, absorbance at a specific wavelength, refractive index, and the like can be preferably used.

The first to third embodiments described below relate to the method for measuring the component concentration of the developer of the present invention.

[First embodiment]
FIG. 1 is a flow chart of a component concentration measuring method according to the present embodiment, which shows a signal flow when the component concentrations of two components of a developing solution are measured from two characteristic values of the developing solution.

In the component concentration calculation method of the present embodiment, first, in the step of measuring the characteristic values a and b of the developing solution, the respective measured values am and bm are acquired. The acquired measured values am and bm are sent to the calculation step. Next, in the calculation step, the measured values am and bm are received, and using these, the component concentrations A and B are calculated by a multivariate analysis method (for example, multiple regression analysis method). In this way, the component concentrations A and B are measured. Further, by repeating this flow, the component concentrations A and B of the developer can be continuously measured.

[Second embodiment]
FIG. 2 is a flow chart of the component concentration measuring method according to the present embodiment, which shows a signal flow when the component concentrations of three or more components of the developing solution are measured from three or more characteristic values of the developing solution. Is.

In the component concentration calculating method of the present embodiment, first, in the step of measuring the characteristic values a, b, c,... Of the developing solution, the respective measured values am, bm, cm,. The acquired measurement values am, bm, cm,... Are sent to the calculation step. Next, in the calculation step, the measured values am, bm, cm,... Are received, and using these, the component concentrations A, B, C,... Are calculated by a multivariate analysis method (for example, multiple regression analysis method). .. In this way, the component concentrations A, B, C,... Are measured. Further, by repeating this flow, the component concentrations A, B, C,... Of the developing solution can be continuously measured.

[Third embodiment]
FIG. 3 shows a signal flow in the case where the calculation step in the case of measuring a plurality of component concentrations from the characteristic values of a plurality of developers also includes a step by a calculation method different from the multivariate analysis method. It is a flowchart of the component concentration measuring method of a form.

This embodiment is preferably adopted when the characteristic value p of the developing solution, which is only related to the concentration P of a certain component of the developing solution, is adopted as the measurement target. More specifically, the alkaline component concentration and the absorbed carbon dioxide concentration of the developer are calculated by a multivariate analysis method from the conductivity value and the density value of the developer, and the dissolved photoresist concentration of the developer is set to a specific wavelength (for example, For example, the linear relationship with the absorbance at λ=560 nm) may be used as a calibration curve for calculation and measurement.

In the method for measuring the component concentration of the developer according to the present embodiment, in the measuring step, the characteristic values a, b,... Of the developer having a plurality of component concentrations as variables and the characteristic values of the developer having only the component concentration P as a variable. are measured, and the measured values am, bm,... And pm,... Are sent to the calculation step.

The calculation step includes a step of calculating the component concentration by a multivariate analysis method (for example, a multiple regression analysis method) and a step of calculating the component concentration by a calculation method different from the multivariate analysis method (for example, a calibration curve method). ,including. It does not matter whether the calculation by these steps is before or after. It may be the same time.

The step of calculating the component concentration by the multivariate analysis method (for example, the multiple regression analysis method) uses the multivariate analysis method (for example, the multiple regression analysis method) from the measured values of the characteristic values a, b,... Of the developer measured in the measurement step. The component concentrations A, B,... Are calculated by the regression analysis method).

In the step of calculating the component concentration by a calculation method different from the multivariate analysis method (for example, a calibration curve method), the linear relationship between the characteristic value p and the component concentration P obtained in advance is used as a calibration curve, The component concentration P,... Is calculated from the measured values of the characteristic values p,... Of the developer measured in the measurement step.

As described above, as described in the first to third embodiments, the method for measuring the component concentration of the developer of the present invention comprises a measurement step of measuring a plurality of characteristic values of the developer that correlates with the component concentration of the developer. And a calculation step of calculating the component concentration of the developing solution by a multivariate analysis method based on the plurality of measured characteristic values.

The measurement step further includes a measurement step of measuring the characteristic value a, a measurement step of measuring the characteristic value b, a measurement step of measuring the characteristic value c, and so on. However, the order of these steps does not matter. It may be measured at the same time. Further, it may include a necessary step depending on the measuring method, such as a temperature adjusting step, a reagent adding step, a waste liquid step, and the like.

The calculation step may include a calculation step of calculating the component concentration by the multivariate analysis method. It may include a step of calculating the component concentration by a calculation method (for example, a calibration curve method) different from the multivariate analysis method.

Hereinafter, the fourth to twelfth embodiments relate to a developer concentration measuring device of the present invention.

[Fourth Embodiment]
FIG. 4 is a schematic diagram of a component concentration measuring device that measures two components of the developer. For convenience of description, the component concentration measuring device A of the developing solution is illustrated together with the developing process equipment B in a state of being connected to the developing process equipment B.

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

The developing process facility B mainly includes a developing solution storage tank 61, an overflow tank 62, a developing chamber hood 64, a roller conveyor 65, a developing solution shower nozzle 67, and the like. The developer is stored in the developer storage tank 61. The developing solution is replenished with a replenishing solution for composition control, but is omitted in FIG. The developing solution storage tank 61 includes a liquid level gauge 63 and an overflow tank 62, and manages an increase in the amount of liquid due to the replenishment of the replenisher. The developing solution storage tank 61 and the developing solution shower nozzle 67 are connected by a developing solution pipeline 80, and the developing solution stored in the developing solution storage tank 61 is filtered by a circulation pump 72 provided in the developing solution pipeline 80. The liquid is sent to the developer shower nozzle 67 via 73. The roller conveyor 65 is provided above the developer storage tank 61 and conveys the substrate 66 on which a photoresist film has been formed. The developing solution is dropped from the developing solution shower nozzle 67, and the substrate 66 conveyed by the roller conveyor 65 is immersed in the developing solution by passing through the dropped developing solution. Then, the developer is collected in the developer storage tank 61 and stored again. Thus, the developing solution is circulated and repeatedly used in the developing process. The developing chamber of a small glass substrate may be subjected to a treatment such that carbon dioxide in the air is not absorbed by filling it with nitrogen gas. The deteriorated developer is drained by operating the waste liquid pump 71.

Next, the developer component concentration measuring apparatus A of the present embodiment will be described. The component concentration measuring device of the present embodiment is a component concentration measuring device of a type in which a developer is sampled to measure a characteristic value.

The developing solution component concentration measuring device A includes a measuring section 1 and a computing section 2, and is connected to a developing solution storage tank 61 by a sampling pipe 15 and a return pipe 16. The measurement unit 1 and the calculation unit 2 are connected by measurement data signal lines 51 and 52.

The measuring unit 1 includes a sampling pump 14 and first measuring means 11 and second measuring means 12 (the first measuring means 11 and the second measuring means 12 may be referred to as measuring means in some cases. is there). The measuring means 11 and 12 are connected in series after the sampling pump 14. It is desirable that the measuring unit 1 further includes temperature adjusting means (not shown) for stabilizing the sampled developer at a predetermined temperature in order to improve the measurement accuracy. At this time, it is preferable that the temperature adjusting means is provided immediately before the measuring means. The sampling pipe 15 is connected to the sampling pump 14 of the measuring unit 1, and the return pipe 16 is connected to the pipe at the end of the measuring means.

The calculation unit 2 includes a calculation block 21 based on the multivariate analysis method. The calculation block 21 based on the multivariate analysis method includes a first measurement unit 11 provided in the measurement unit 1 by a measurement data signal line 51 and a second measurement unit provided in the measurement unit 1 by a measurement data signal line 52. It is connected to the means 12.

Next, the measurement operation and the calculation operation of the component concentration measuring device A will be described.

The developer collected from the developer storage tank 61 by the sampling pump 14 is introduced into the measuring section 1 of the component concentration measuring device A through the sampling pipe 15. After that, when the temperature adjusting means is provided, the sampled developing solution is sent to the temperature adjusting means, maintained at a predetermined measurement temperature (for example, 25° C.), and then sent to the measuring means 11 and 12. .. The characteristic value a of the developing solution is measured by the first measuring means, and the characteristic value b of the developing solution is measured by the second measuring means. The developer after measurement is returned to the developer storage tank 61 through the return pipe 16.

The measured value am of the characteristic value a of the developing solution measured by the first measuring means 11 and the measured value bm of the characteristic value b of the developing solution measured by the second measuring means 12 are measured data respectively. It is sent to the operation block 21 by the multivariate analysis method via the signal lines 51 and 52. The calculation block 21, which has received the measured values am and bm, calculates these measured values by the multivariate analysis method to calculate the component concentrations A and B of the developer. Thus, the component concentrations A and B of the developer are measured by the component concentration measuring device A.

[Fifth Embodiment]
FIG. 5 is a schematic diagram of a component concentration measuring device that measures three components of the developer. The developing solution component concentration measuring device A includes a measuring unit 1 and a computing unit 2, and is connected to a developing process facility B (developing liquid storage tank 61) through a sampling pipe 15 and a return pipe 16. The measuring unit 1 includes a first measuring unit 11, a second measuring unit 12, and a third measuring unit 13, which measure three characteristic values of the developing solution. The measured values of the three measured characteristic values are sent to the calculation unit 2 via the measurement data signal lines 51, 52 and 53, and the component concentrations of the three components of the developer are determined by the multivariate analysis method. It is calculated. The description of the measurement operation, the calculation operation, and the members overlapping with those in FIG.

[Sixth embodiment]
FIG. 6 is a schematic diagram of a component concentration measuring apparatus having a calculation block in the calculation unit 2 by a calculation method different from the multivariate analysis method. For example, it is applied when there is a set of the characteristic value and the component concentration of the developer capable of measuring the component concentration of the developer from the measured physical property value of the developer by the calibration curve method or the like.

The component concentration measuring apparatus A of the present embodiment includes a measuring unit 1 that measures a plurality of characteristic values of a developing solution, and a calculation unit 2 that calculates the component concentration of the developing solution from the measured values. The calculation unit 2 includes a calculation block 21 based on a multivariate analysis method and a calculation block 22 based on a calculation method other than the multivariate analysis method (for example, a calibration curve method).

The measured value of the characteristic value of the developer used for the calculation by the multivariate analysis method is measured by the measuring unit 1 and then sent to the calculation block 21 by the multivariate analysis method of the calculation unit 2. The measured values of the characteristic values of the developer used in the calculation method other than the multivariate analysis method (for example, the calibration curve method) are sent to the calculation block 22. The component concentrations of the developer are calculated by performing the calculations in the calculation blocks 21 and 22.

Note that there may be a plurality of calculation blocks 22 using a calculation method other than the multivariate analysis method (for example, a calibration curve method). Regarding the calculation by the multivariate analysis method and the calculation by other methods (for example, the calibration curve method), the calculation order does not matter. In addition, the description of members and the like that overlap with those of the fourth and fifth embodiments will be omitted.

[Seventh embodiment]
FIG. 7 is a schematic diagram of a component concentration measuring device in which the measuring unit 1 and the calculating unit 2 are separately configured.

In the component concentration measuring apparatus A of the present embodiment, the measuring unit 1 is provided in a pipeline bypassed from the developing solution pipeline 80 of the developing process equipment B, and is connected to the arithmetic unit 2 by the measurement data signal lines 51 to 53. Has been done. It may be directly connected to the developer line 80 or another line. Instead of the sampling pump 14, a flow rate control valve (not shown) or the like may be used in combination.

[Eighth Embodiment]
FIG. 8 is a component concentration measuring device in the case where the measuring means 11 to 13 for measuring the characteristic value of the developer are composed of measuring device bodies 11a, 12a and 13a and measuring probes 11b, 12b and 13b, respectively. FIG.

In this embodiment, the characteristic values of the developing solution are measured by immersing the measuring probes 11b to 13b of the measuring means 11 to 13 in the developing solution stored in the developing solution storage tank 61. The measured characteristic value of the developing solution is sent to the calculation unit 2 via the measurement data signal lines 51 to 53. The component concentration of the developer is measured by calculating the component concentration by the calculation unit 2 by the multivariate analysis method.

Although FIG. 8 shows the case where the measuring unit 1 and the calculating unit 2 are separately configured, the component concentration measuring device may be integrally configured. In this case, the measuring probe immersed in the developer and the measuring device main body arranged in the measuring unit 1 of the component concentration measuring device are connected by a cable or the like.

[Ninth Embodiment]
FIG. 9 is a schematic diagram of a component concentration measuring device in which the measuring means in the measuring unit 1 are arranged in parallel and provided.

The respective measuring means constituting the measuring unit 1 are not limited to being connected in series and may be connected in parallel. As shown in FIG. 9, the measuring means 11 to 13 may independently include the sampling pipe lines 15a to 15c, the sampling pumps 14a to 14c, the return pipes 16a to 16c, and the like, and the pipe lines branched in the middle thereof. May be connected in parallel by. The characteristic values of the developing solution measured by the measuring means 11 to 13 are sent to the arithmetic unit 2. The calculation unit 2 calculates the component concentration of the developer by the multivariate analysis method.

[Tenth Embodiment]
FIG. 10 is a schematic diagram of a component concentration measuring device including a measuring device that requires addition of a drug, such as an automatic titrator. In FIG. 10, the third measuring means 13 is a measuring device that requires addition of a drug.

In this case, the third measuring means 13 is connected to the sampling pipe 15 and the sampling pump 14, and is also connected to the additive reagent 93 via the liquid sending pipe 18. The added reagent is sampled by a liquid feed pump and provided for measurement. The developer after the measurement is drained by the drain pipe 19. Other than that, the measurement operation and the calculation operation are the same as those in the other embodiments, and will be omitted.

As described above, as shown in the fourth to tenth embodiments, the component concentration measuring device of the present invention includes a measuring unit 1 for measuring a plurality of characteristic values of the developing solution that correlates with the component concentration of the developing solution, and a measuring unit 1. And a calculation unit 2 for measuring the component concentration of the developing solution by the multivariate analysis method based on the plurality of characteristic values of the developing solution measured by the section 1.

The measuring unit 1 of the component concentration measuring apparatus A of this embodiment can take various embodiments. Since the measuring device used for the measuring means has a suitable installation and connection method according to the measuring method adopted by the measuring device, the measuring unit 1 of the component concentration measuring device of the present invention is optimal according to the measuring means. It may be configured as follows.

It suffices that the measuring unit 1 be provided with a measuring unit necessary for measuring a plurality of characteristic values of the developing solution. It is desirable to have a temperature control means (not shown). The sampling pump 14, the liquid feed pump 17, the waste liquid pipe 19, and the like are preferably provided as needed, but none of them is essential as an internal component of the measurement unit 1.

The measurement unit 1 and the calculation unit 2 may be integrated or separated. It suffices that the measurement unit 1 and the calculation unit 2 communicate with each other so that the calculation unit 2 can receive the measurement data of the characteristic value of the developer measured by the measurement unit 1. The measurement unit 1 and the calculation unit 2 are not limited to being connected by a signal line, but may be configured to be capable of wirelessly transmitting and receiving data. It is not necessary that a plurality of measuring means are integrated in one place to configure the measuring unit 1, and only one specific measuring means may be separately provided.

Each measuring means is not limited to the method of sampling and measuring, but may be the method of directly attaching to the pipe or the method of immersing the probe in the liquid. Each measuring means may be connected in series or in parallel. The measurement unit 1 may be configured by these various combinations.

It should be noted that the measurement of the plurality of characteristic values of the developer in the measuring unit 1 of the present embodiment does not matter in the order. Arrangement of each measuring means in the measuring unit 1 in the drawings from FIG. 4 to FIG. 10, and “first”, “first measuring means”, “second measuring means”,... Words such as "second",... Do not limit the order of measurement in the present invention. Words such as "first", "second",... Are merely convenient for distinguishing each of a plurality of measuring means.

Further, if the calculation unit 2 of the component concentration measuring apparatus of the present embodiment includes the calculation block 21 based on the multivariate analysis method, it has a calculation block based on a method other than the multivariate analysis method (for example, a calibration curve method) separately. May be. At this time, the order of calculation does not matter.

In the component concentration measuring apparatus of the present embodiment, each measuring unit constituting the measuring unit 1 is installed and connected in an arrangement suitable for the measuring method, measures a plurality of characteristic values of the developing solution, and the calculating unit 2 By receiving the measured value of the characteristic value of the developer measured by the measuring unit 1, the component concentration of the developer is calculated by the multivariate analysis method (including the calculation method).

Hereinafter, application examples of the component concentration measuring apparatus according to the present embodiment in the eleventh and twelfth embodiments will be described. The component concentration measuring device of this embodiment can be applied to various devices and systems as one component.

[Eleventh Embodiment]
FIG. 11 is a schematic diagram of a developing solution management apparatus using the component concentration measuring apparatus of this embodiment.

In the present embodiment, the component concentration measuring device A is connected to the control unit 3 (control device) that controls the control valves 41 to 43 by the calculation data signal line 54. The control unit 3 (control device) is connected to the control valves 41 to 43 by signal lines 55 to 57 for control signals. The control valves 41 to 43 are provided with replenishing liquid conduits 81 and 82 for feeding the replenishing liquid from the replenishing liquid storage tanks 91 and 92, and a pure water conduit 83 for feeding the pure water. , Are provided in.

The replenisher storage tanks 91 and 92 are pressurized with nitrogen gas, and the control unit 3 (control device) opens and closes the control valves 41 to 43 so that the replenisher solution passes through the confluent conduit 84 and becomes a developer. Will be replenished. The replenishing liquid to be replenished is returned to the developer storage tank 61 by the circulation pump 74 via the circulation pipe line 85 and is stirred. The method and mechanism of the replenishing operation of the replenisher will be described in the embodiment of the developer managing method and the developer managing apparatus described later.

As described above, the component concentration measuring apparatus according to the present embodiment is combined with the control valve provided in the flow path for feeding the replenisher solution to be replenished to the developing solution, and the control apparatus for controlling these, thereby developing It can be used as a part of the liquid management device.

Note that the replenishing solution means, for example, a stock solution of a developing solution, a new solution, a regenerating solution, or the like. Pure water may be included. The undiluted solution is an unused developing solution (for example, 20 to 25% TMAH aqueous solution) having a high alkaline component concentration. The new solution is an unused developing solution (for example, 2.38% TMAH aqueous solution) having the same concentration of the alkaline component as that used in the developing step. The regenerating solution is a developing solution that is made reusable by removing unnecessary substances from the used developing solution. These have different uses and effects as replenishers. For example, the undiluted solution is a replenisher for increasing the concentration of alkaline components, and reduces the concentration of dissolved photoresist and the concentration of absorbed carbon dioxide. The new liquid is a replenishing liquid for maintaining or gently increasing/decreasing the concentration of the alkaline component to reduce the dissolved photoresist concentration and the absorbed carbon dioxide concentration. Pure water is a replenisher for reducing the concentration of each component. The same applies to the following description of the embodiments.

Further, in FIG. 11, the case where the replenishing liquid is supplied from the replenishing liquid storage tanks 91 and 92 through the replenishing liquid pipes 81 and 82, and the pure water is supplied through the pure water pipe 83 is illustrated. However, it is not limited to this. The replenisher may be sent from the replenisher reservoirs 91, 92, etc. to a mixing tank (not shown) where it is adjusted to a predetermined concentration and then delivered to the developer reservoir 61. In this case, the control valve is provided in the middle of the pipeline for feeding the liquid from the blending tank to the developer storage tank 61. Pure water may not be directly supplied to the developer storage tank 61, and at this time, the pure water conduit 83 and the control valve 43 do not exist. The same applies to the following description of the embodiments and the following drawings.

The replenisher is stored in the replenisher reservoirs 91 and 92 of the replenisher reservoir C. The replenisher storage tanks 91 and 92 are connected to a nitrogen gas pipeline 86 equipped with pressurized gas valves 46 and 47, and are pressurized by nitrogen gas supplied through the pipelines. Further, replenisher reservoirs 91 and 92 are connected to replenisher conduits 81 and 82, respectively, and the replenisher is delivered via valves 44 and 45 that are normally open. The replenisher lines 81, 82 and the pure water line 83 are provided with control valves 41 to 43, and the control valves 41 to 43 are controlled to be opened and closed by the control unit 3. By operating the control valve, the replenisher stored in the replenisher reservoirs 91 and 92 is pressure-fed, and pure water is fed. After that, the replenisher is merged with the circulation stirring mechanism D through the merge conduit 84, and is replenished and stirred in the developer storage tank 61.

When the replenishing liquid stored in the replenishing liquid storage tanks 91, 92 decreases due to replenishment, the internal pressure decreases and the supply amount becomes unstable. It is opened appropriately to supply nitrogen gas, and the internal pressures of the replenisher storage tanks 91 and 92 are maintained. When the replenisher tanks 91 and 92 are empty, the valves 44 and 45 are closed and replaced with a new replenisher tank filled with replenisher, or the separately procured replenisher tank is emptied. The replenisher storage tanks 91 and 92 are filled again.

[Twelfth Embodiment]
The component concentration measuring device of the present embodiment can be used as a component concentration monitor or a component concentration monitoring device of a developer in combination with the display device DP. Furthermore, it can be applied to a developer concentration abnormality warning device or the like in combination with the warning light WL and the warning device WT. FIG. 12 is a schematic view showing an application example of the component concentration measuring apparatus of the present invention. As described above, the component concentration measuring device of the present invention can be applied as various parts to various devices and systems.

Hereinafter, the thirteenth to seventeenth embodiments relate to the developer management method of the present invention.

The developing solution management method of the present invention comprises a measuring step of measuring a plurality of characteristic values of the developing solution which are correlated with the component concentration of the alkaline developing solution, and a component of the developing solution by a multivariate analysis method from the measured plurality of characteristic values. It includes a calculation step of calculating the concentration and a replenishment step of replenishing the replenisher with the developer based on either the measured characteristic value of the developer or the calculated component concentration of the developer. Since the measurement step and the calculation step are the same as the measurement step and the calculation step in the above-described method for measuring the component concentration of the developing solution, the overlapping description thereof will be omitted in the following thirteenth to seventeenth embodiments. ..

In addition, in the following description, the "predetermined control value" is known in advance as a characteristic value or a component concentration value when the developer exhibits optimum liquid performance, empirically, or through experiments. Is the characteristic value or component concentration value. That is, a numerical value that is an index of the developing performance of the developing solution such as a line width and a residual film thickness formed on the substrate after development is known in advance as a characteristic value or a component concentration value that provides the most preferable state. It refers to the existing value. The “predetermined management area” is also a range of such management values. The same applies to the description of the developing solution management apparatus.

[Thirteenth Embodiment]
FIG. 13 is a flow chart of a developing solution management method for managing two components of the developing solution according to the component concentrations. The developing solution management method of the present embodiment, in an alkaline developing solution which is managed so as to absorb less carbon dioxide, so that the concentration of the alkaline component of the developing solution becomes a predetermined control value, and the dissolved photoresist concentration is It is preferably applied when controlling the developing solution so that the value becomes a predetermined control value or less.

In this embodiment, the component concentration A is controlled to a predetermined control value A0 and the component concentration B is controlled to a predetermined control value B0 or less. The component concentration A is, for example, an alkaline component concentration, and the component concentration B is, for example, a dissolved photoresist concentration.

The characteristic values a and b of the developer are measured in the measuring step, and the measured values am and bm are sent to the calculation step. In the calculation step, the component concentrations A and B of the developer are measured from the measured values am and bm by the multivariate analysis method. The component concentrations A and B calculated in the calculation step are sent to the replenishment step.

The replenishment step includes a step of adjusting the component concentration A and a step of adjusting the component concentration B.

First, in the step of adjusting the component concentration A, it is determined whether the component concentration A is larger or smaller than the control value A0. When it is larger, a replenisher (for example, a new developer or pure water) that works to dilute the component concentration A is replenished to the developer. When it is small, a replenisher (for example, a developer undiluted solution or a new solution) that works to increase the component concentration A is replenished to the developer. When the component concentration A is the same as the control value A0, nothing is done.

In the step of adjusting the component concentration B, it is determined whether the component concentration B is larger than the control value B0. When it is larger, a replenisher that works to dilute the component concentration B (for example, a new developer is preferable because it does not change the alkaline component concentration) is replenished to the developer. When I'm small, I don't do anything.

[Fourteenth embodiment]
FIG. 14 is a flow chart of a developing solution management method in which one of the two components of the developing solution is managed by the component concentration and the other is managed by the characteristic value. The developing solution management method of the present embodiment is an alkaline developing solution which is managed so that the absorption of carbon dioxide is small, so that the concentration of the alkaline component of the developing solution becomes a predetermined management value, and the specific wavelength of the developing solution. It is preferably applied when the developing solution is managed such that the absorbance at (for example, λ=560 nm) is below a predetermined control value.

In the present embodiment, the component concentration A is controlled to a predetermined control value A0, and the measured value bm of the developer characteristic value b is controlled to a predetermined control value b0 or less. The component concentration A is, for example, the concentration of an alkaline component, and the characteristic value b is, for example, the absorbance at a specific wavelength (for example, λ=560 nm).

The characteristic values a and b of the developer are measured in the measuring step, and the measured values am and bm are sent to the calculation step. In the calculation step, the component concentrations A and B of the developer are measured from the measured values am and bm by the multivariate analysis method. The component concentration A calculated in the calculation step and the measured value bm of the characteristic value b measured in the measurement step are sent to the replenishment step.

The replenishment step includes a step of adjusting the component concentration A and a step of adjusting the characteristic value b. The step of adjusting the component concentration A is the same as in the case of the thirteenth embodiment, and therefore its explanation is omitted.

In the step of adjusting the characteristic value b, it is determined whether the measured value bm is larger than the control value b0. When it is larger, a replenisher that works to dilute the component concentration B (for example, a new developer is preferable because it does not change the alkaline component concentration) is replenished to the developer. When I'm small, I don't do anything.

When the characteristic value b and the component concentration B have a monotonically increasing correlation, the characteristic value b is controlled to be the control value b0 or less, so that the component concentration B is controlled to be the control value B0 or less. It will be. When the characteristic value b and the component concentration B have a monotonically decreasing correlation, the component concentration B can be managed so as to be equal to or less than the control value B0 by operating by reversing the magnitude relationship of the determination.

[Fifteenth embodiment]
FIG. 15 is a flow chart of a developing solution management method for managing the three components of the developing solution according to the component concentrations. The developing solution management method of the present embodiment, for example, the alkaline component concentration of the developing solution to a predetermined management value, the dissolved photoresist concentration to a predetermined management value or less, and the absorbed carbon dioxide concentration to a predetermined management value or less. It is preferably applied when managing.

In the replenishment step, the component concentration A is controlled to a predetermined control value A0, the component concentration B is controlled to a predetermined control value B0 or less, and the component concentration C is controlled to a predetermined control value C0 or less. The component concentration A is, for example, an alkaline component concentration, the component concentration B is, for example, a dissolved photoresist concentration, and the component concentration C is, for example, an absorbed carbon dioxide concentration.

The characteristic values a, b, c,... Of the developing solution are measured in the measuring step, and the measured values am, bm, cm,. In the calculation step, the component concentrations A, B, C,... Of the developing solution are measured from the measured values am, bm, cm,... By the multivariate analysis method. The component concentrations A, B, C,... Calculated in the calculation step are sent to the replenishment step.

The replenishment step includes a step of adjusting the component concentration A, a step of adjusting the component concentration B, and a step of adjusting the component concentration C.

First, in the step of adjusting the component concentration A, it is determined whether the component concentration A is larger or smaller than the control value A0. When it is larger, a replenisher (for example, a new developer or pure water) that works to dilute the component concentration A is replenished to the developer. When it is small, a replenisher (for example, a developer undiluted solution or a new solution) that works to increase the component concentration A is replenished to the developer. When the component concentration A is the same as the control value A0, nothing is done.

In the step of adjusting the component concentration B, it is determined whether the component concentration B is larger than the control value B0. When it is larger, a replenisher that works so as to dilute the component concentration B (for example, a new developer is preferable because it does not change the alkaline component concentration) is replenished to the developer. When I'm small, I don't do anything.

In the step of adjusting the component concentration C, it is determined whether the component concentration C is larger than the control value C0. When it is larger, a replenisher that works to dilute the component concentration C (for example, a new developer is preferable because it does not change the alkaline component concentration) is replenished to the developer. When I'm small, I don't do anything.

[Sixteenth Embodiment]
FIG. 16 is a flow chart of a developing solution management method in which one of the three components of the developing solution is managed by the characteristic value and the other two are managed by the component concentration. In the developing solution management method of the present embodiment, the absorbance at a specific wavelength of the developing solution (for example, λ=560 nm) becomes equal to or less than a predetermined management value so that the concentration of the alkaline component of the developer becomes a predetermined management value. Further, it is preferably applied when controlling the developing solution such that the absorbed carbon dioxide concentration of the developing solution becomes a predetermined control value or less.

In this embodiment, the component concentration A is controlled to a predetermined control value A0, the measured value bm of the developer characteristic value b is controlled to a predetermined control value b0 or less, and the component concentration C is controlled to a predetermined control value C0 or less. To do. The component concentration A is, for example, the alkali component concentration, the characteristic value b is, for example, the absorbance at a specific wavelength (for example, λ=560 nm), and the component concentration C is, for example, the absorbed carbon dioxide concentration.

In the measuring step, the characteristic values a, b, c of the developer are measured, and the measured values am, bm, cm are sent to the calculation step. In the calculation step, the component concentrations A, B and C of the developing solution are measured from the measured values am, bm and cm by the multivariate analysis method. The component concentrations A and C calculated in the calculation step and the measured value bm of the characteristic value b measured in the measurement step are sent to the replenishment step.

The replenishment step includes a step of adjusting the component concentration A, a step of adjusting the characteristic value b, and a step of adjusting the component concentration C. Since the step of adjusting the component concentration A and the step of adjusting the component concentration C are the same as those in the fifteenth embodiment, the description thereof will be omitted.

In the step of adjusting the characteristic value b, it is determined whether the measured value bm is larger than the control value b0. When it is larger, a replenisher that works to dilute the component concentration B (for example, a new developer is preferable because it does not change the alkaline component concentration) is replenished to the developer. When I'm small, I don't do anything.

When the characteristic value b and the component concentration B have a monotonically increasing correlation, the characteristic value b is controlled to be the control value b0 or less, so that the component concentration B is controlled to be the control value B0 or less. It will be. When the characteristic value b and the component concentration B have a monotonically decreasing correlation, by reversing the magnitude relationship of the determination (that is, bm<b0) to operate, the component concentration B becomes the control value B0 or less similarly. Can be managed to be.

[Seventeenth Embodiment]
FIG. 17 is a flow chart of a developing solution management method in which two out of the three components of the developing solution are managed by the characteristic value and the other one is managed by the component concentration. The developing solution management method of this embodiment is such that the conductivity of the developing solution has a predetermined management value, the absorbance of the developing solution at a specific wavelength (for example, λ=560 nm) is not more than a predetermined management value, and It is preferably applied when the developing solution is controlled such that the absorbed carbon dioxide concentration of the developing solution is below a predetermined control value.

In this embodiment, the measured value am of the characteristic value a of the developer is set to a predetermined control value a0, the measured value bm of the characteristic value b of the developer is set to a predetermined control value b0 or less, and the component concentration C is set to a predetermined control value. It shall be managed below C0. The characteristic value a is, for example, the conductivity, the characteristic value b is, for example, the absorbance at a specific wavelength (for example, λ=560 nm), and the component concentration C is, for example, the absorbed carbon dioxide concentration.

In the measuring step, the characteristic values a, b, c of the developer are measured, and the measured values am, bm, cm are sent to the calculation step. In the calculation step, the component concentrations A, B and C of the developing solution are measured from the measured values am, bm and cm by the multivariate analysis method. The measurement value am of the characteristic value a measured in the measurement step, the measurement value bm of b, and the component concentration C calculated in the calculation step are sent to the replenishment step.

The replenishment step includes a step of adjusting the characteristic value a, a step of adjusting the characteristic value b, and a step of adjusting the component concentration C. Since the step of adjusting the characteristic value b and the step of adjusting the component concentration C are the same as those in the sixteenth embodiment, description thereof will be omitted.

In the step of adjusting the characteristic value a, it is determined whether the measured value am is larger or smaller than the control value a0. When it is larger, a replenisher solution (for example, a developing solution stock solution or a new solution) that works to dilute the component concentration A is supplied to the developing solution. When it is small, a replenisher (for example, a new developer or pure water) that works to increase the component concentration A is replenished to the developer. If they are the same, do nothing.

When the characteristic value a and the component concentration A have a monotonically increasing correlation, the characteristic value a is maintained at the control value a0, so that the component concentration A is controlled to become the control value A0. Become. When the characteristic value a and the component concentration A have a monotonically decreasing correlation, by reversing the magnitude relationship of the determination to operate, the component concentration A can be managed so that it becomes the control value A0.

As described above, as shown in the thirteenth to seventeenth embodiments, the developing solution management method of the present invention comprises a measuring step of measuring a plurality of characteristic values of the developing solution which are correlated with the component concentration of the developing solution, Select from the calculation step of calculating the component concentration of the developer by the multivariate analysis method based on the measured multiple characteristic values, and the multiple characteristic values of the measured developer and the calculated component concentration of the developer. And a replenishing step of replenishing the developer with a replenisher based on the measured value or calculated value of the managed item.

The measurement step further includes a measurement step of measuring the characteristic value a, a measurement step of measuring the characteristic value b, a measurement step of measuring the characteristic value c, and so on. However, the order of these steps does not matter. It may be measured at the same time. Further, it may include a necessary step depending on the measuring method, such as a temperature adjusting step, a reagent adding step, a waste liquid step, and the like.

The calculation step may include a calculation step of calculating the component concentration by the multivariate analysis method. It may include a step of calculating the component concentration by a calculation method (for example, a calibration curve method) different from the multivariate analysis method.

In the replenishment step, the control target item (either the characteristic value of the developing solution or the component concentration) is used as a control amount, and this is set to a predetermined control value, or below the predetermined control value or within the control area. Includes a step of replenishing the replenisher with the developing solution, a step of adjusting the component concentration A, a step of adjusting the component concentration B, a step of adjusting the component concentration C, and so on. The order is not limited to the order shown in the drawings.

Further, as the control method, various control methods used for controlling the control amount to match the target value can be adopted. In particular, proportional control (P control), integral control (I control), differential control (D control), and control (PI control etc.) combining these are preferable. More preferably, PID control is suitable.

In the thirteenth to seventeenth embodiments, by repeating the measurement step, the calculation step, and the replenishment step, the component concentration A of the developer is maintained at its control value A0, and the component concentration B of the developer is The component concentration C is managed below the control value B0, and the component concentration C is managed below the control value C0. Therefore, the developing solution management method of the present invention can maintain the optimum developing performance and realize the desired line width and residual film thickness.

Hereinafter, the eighteenth to twenty-fifth embodiments relate to the developer management apparatus of the present invention.

The developing solution management apparatus according to the present embodiment is configured to measure a plurality of characteristic values of a developing solution having a correlation with a component concentration of an alkaline developing solution, and a multivariate analysis based on the plurality of characteristic values measured by the measuring section 1. Calculation unit 2 for calculating the component concentration of the developer by the method, and replenishment to be replenished to the developer based on the characteristic value of the developer measured by the measuring unit 1 or the component concentration of the developer calculated by the calculation unit 2. The control unit 3 that issues a control signal to the control valves 41 to 43 provided in the flow path for feeding the liquid. The measuring unit 1 and the calculating unit 2 of the developer managing apparatus of the present invention are the same as the measuring unit 1 and the calculating unit 2 in the above-described developer component concentration measuring apparatus, and therefore, the following 18th to 25th. In the above-described embodiments, the overlapping description will be omitted.

[Eighteenth Embodiment]
FIG. 18 is a schematic diagram of a developing process for explaining the developing solution management apparatus of the present invention. A developing solution management apparatus E of the present invention is shown together with a developing process facility B, a replenisher storage section C, a circulation stirring mechanism D, and the like.

The developing solution management apparatus E of this embodiment includes a measuring section 1 including a plurality of measuring means 11 to 13 for measuring a plurality of characteristic values of a developing solution, and a computing section 2 including a computing block 21 based on the multivariate analysis method. The control unit 3 controls either the characteristic value of the developing solution or the component concentration as a control amount so as to be a predetermined control value or within a control region. Further, the developing solution management apparatus of this embodiment includes control valves 41 to 43 that are connected to and controlled by the control unit 3.

The developer management device E is connected to the developer storage tank 61 by the sampling pipe 15. The developer sampled by the sampling pump 14 is introduced into the measuring unit 1 through the sampling pipe 15. In the measuring unit 1, each measuring means 11 to 13 measures the characteristic value of the developing solution. The developer after measurement is returned to the developer storage tank 61 through the return pipe 16.

The calculation unit 2 receives a set of measured values of a plurality of characteristic values of the developer measured by the measurement unit 1. The calculation unit 2 calculates the component concentration of the developer from the set of received measurement values by the multivariate analysis method.

The details of the measurement operation and the calculation operation are the same as those of the above-described developing solution component concentration measuring apparatus, and therefore are omitted, and the control operation will be described below.

The developing solution management device E is connected to the conduits 81 to 83 for feeding a replenishing solution to be replenished with the developing solution (including pure water as a replenishing solution). Each of the pipelines 81 to 83 is connected to the control valves 41 to 43 whose operations are controlled by the controller 3 in the developing solution management apparatus E.

The control unit 3 receives the measured value of the characteristic value of the developer from the measurement unit 1 and the calculated component concentration from the calculation unit 2. The control unit 3 uses the received characteristic value or component concentration of the developer as a control amount, and issues a control signal to the control valves 41 to 43 based on this control amount. The control is performed, for example, so that the control amount becomes a predetermined management value or within a predetermined management area.

The control unit 3 includes a control block. For example, if the developing solution management device E manages the three component concentrations A, B, and C of the developing solution, the control unit 3 controls the control block 31 for controlling the component concentration A and the component concentration B. And a control block 33 for controlling the component concentration C. If the component concentration to be managed is two, the control block may be two, and if the component concentration to be managed is more than three, a similar control block is further provided accordingly. In this way, the control unit 3 can issue the necessary control signals to the control valves 41 to 43.

When the control valves 41 to 43 are, for example, control valves that are opened while receiving an “open” signal and are open/close control valves whose flow rate is adjusted in advance so as to deliver a predetermined flow rate when the valves are opened. Is required by the control unit 3 by sending an "open" signal to a control valve provided in a flow path for supplying a replenisher to be replenished for a predetermined time. The developer is replenished in an amount.

The control operation of the control valve is not limited to this example. When the control valve switches the open state and the closed state of the valve according to the open/close switching signal, the control unit 3 sends a pulse-like open/close switching signal to the control valve at a predetermined time interval so that necessary replenishment is performed. The required amount of liquid is added to the developer.

Further, the control valves 41 to 43 may be capable of controlling the opening degree of the valves, or may be a simple combination of a flow rate adjusting valve (needle valve) and an opening/closing control valve. The control valves 41 to 43 may be electromagnetic valves or may be pneumatically operated valves (air operated valves).

By operating the control valves 41 to 43 based on the control signal generated by the control unit 3, the developer is replenished with the replenisher in an amount necessary for managing the developer. The control unit 3 controls so that the required replenishment amount is delivered based on the type of replenisher liquid obtained from the received control amount (characteristic value or component concentration of the developer) and the necessary replenishment amount. It issues a control signal to the control valve to be controlled.

In this way, the developing solution management apparatus according to the present embodiment uses the measured characteristic values of the developing solution or the calculated component concentrations of the developing solution so that these values become predetermined control values, or It is possible to maintain and manage the developing solution so that it is within the control area.

More specifically, the following developer management is possible. However, the following developer management is an example and is not limited to this.

First, development in which a replenisher is replenished to the developer so that the alkaline component concentration, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration of the repeatedly used alkaline developer have predetermined control values for each. Liquid management. For example, according to the developer management apparatus of the present invention, the alkali component concentration of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 2.375 to 2.390 (wt %), and more preferably 2.380 (wt%), dissolved photoresist concentration, preferably a predetermined control value of 0.40 (wt%) or less, more preferably 0.15 (wt%), absorbed carbon dioxide concentration, Can be controlled to a predetermined control value of 0.40 (wt%) or less, and more preferably to 0.25 (wt%).

Secondly, in order to keep the alkaline component concentration of the repeatedly used alkaline developer at a predetermined control value, the dissolved photoresist concentration and the absorbed carbon dioxide concentration should be below a predetermined control value for each developer. It is a developer management that replenishes the replenisher. For example, according to the developer management apparatus of the present invention, the alkali component concentration of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 2.375 to 2.390 (wt %), and more preferably 2.380 (wt%) so that the dissolved photoresist concentration is preferably 0.40 (wt%) or less, and the absorbed carbon dioxide concentration is preferably 0.40 (wt%) or less Can be managed.

Thirdly, development in which the replenisher is replenished so that the alkaline component concentration of the repeatedly used alkaline developer, the absorbance at a specific wavelength, and the absorbed carbon dioxide concentration have predetermined control values for each. Liquid management. For example, according to the developer management apparatus of the present invention, the alkali component concentration of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 2.375 to 2.390 (wt %), and more preferably 2.380 (wt %), the absorbance at the wavelength λ=560 nm (cell optical path length d=10 mm), a predetermined control value of preferably 1.30 (Abs.) or less, more preferably 0.50 (Abs. ), the absorbed carbon dioxide concentration can be controlled to a predetermined control value of preferably 0.40 (wt%) or less, and more preferably to 0.25 (wt%).

Fourth, so that the alkaline component concentration of the repeatedly used alkaline developer is a predetermined control, so that the absorbance at a specific wavelength is within a predetermined control region, the absorbed carbon dioxide concentration is below a predetermined control value. As described above, the developer is managed by replenishing the replenisher with the developer. For example, according to the developer management apparatus of the present invention, the alkali component concentration of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 2.375 to 2.390 (wt %), and more preferably The absorbance at a wavelength λ=560 nm (cell optical path length d=10 mm) of 2.380 (wt %) is preferably 1.30 (Abs.) or less, more preferably 0.65 (Abs.) or less. In addition, the absorbed carbon dioxide concentration can be controlled so as to be preferably 0.40 (wt%) or less.

Fifth, the developer management that replenishes the replenisher with the conductivity, the absorbance at a specific wavelength, and the absorbed carbon dioxide concentration of the repeatedly used alkaline developer have predetermined control values for each. Is. For example, according to the developer management apparatus of the present invention, the conductivity of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 54.47 to 54.75 (mS/cm), more preferably At 54.58 (mS/cm), the absorbance at the wavelength λ=560 nm (cell optical path length d=10 mm) is set to a predetermined control value of preferably 1.3 (Abs.) or less, more preferably 0.50 (Abs). .), the absorbed carbon dioxide concentration can be controlled to a predetermined control value of preferably 0.40 (wt%) or less, and more preferably to 0.25 (wt%).

Sixth, so that the conductivity of the alkaline developer used repeatedly has a predetermined control value, the absorbance at a specific wavelength is within a predetermined control region, and the absorbed carbon dioxide concentration is not more than a predetermined control value. As described above, the developer is managed by replenishing the replenisher with the developer. For example, according to the developer management apparatus of the present invention, the conductivity of the 2.38% TMAH aqueous solution is preferably a predetermined control value within the range of 54.47 to 54.75 (mS/cm), more preferably At 54.58 (mS/cm), the absorbance at the wavelength λ=560 nm (cell optical path length d=10 mm) is preferably 1.30 (Abs.) or less, more preferably 0.65 (Abs.) or less. Thus, the absorbed carbon dioxide concentration can be controlled so as to be preferably 0.40 (wt%) or less.

Therefore, according to the developing solution management apparatus of the present embodiment, compared to the conventional one, each component concentration or each characteristic value of the developing solution can be managed more accurately within a predetermined management value or management area. It is possible to maintain the optimum developing performance and to realize a desired line width and residual film thickness.

[Nineteenth Embodiment]
FIG. 19 illustrates the developing solution management apparatus of the embodiment in which the control valves 41 to 43 provided in the flow path for feeding the replenisher solution to be supplied to the developing solution are outside the developing solution management apparatus of the present embodiment. It is a schematic diagram for doing.

The developing solution management apparatus E of the present embodiment includes a measuring section 1 including a plurality of measuring means for measuring a plurality of characteristic values of the developing solution, a computing section 2 including a computing block 21 based on the multivariate analysis method, and a developing solution. Of the control values 41 to 43 provided in the replenishment replenishing conduit so as to be within a predetermined control value or control region by using either the characteristic value or the component concentration of the control value as a control amount. 3 and 3 are provided.

In this embodiment, the control valves 41 to 43 controlled by the control unit 3 are not internal parts of the developer management apparatus E. As a separate body from the developing solution management apparatus E, the developing solution management apparatus E is provided in a pipe line through which a replenisher solution is sent. The developing solution management device E is not connected to these conduits through which the replenisher solution is sent.

Other configurations, operations, etc. are similar to those of the eighteenth embodiment, and will be omitted.

[Twentieth Embodiment]
FIG. 20 is a schematic diagram of a developing solution management apparatus E including an arithmetic control unit 23 having both arithmetic functions and control functions.

The developer management apparatus E of the present invention is not limited to the case where the calculation unit 2 and the control unit 3 are configured as separate devices. It may be configured as an integral arithmetic control unit 23 having both an arithmetic function and a control function. As the arithmetic control unit 23, for example, a multi-function device such as a computer can be used.

Computers have a wide variety of functions such as input/output functions, transmission/reception functions, arithmetic functions, control functions, and display functions. Therefore, the calculation function and the control function of the developing solution management apparatus E of the present invention can be realized by a computer. It suffices that the arithmetic and control unit 23 be connected to the measuring unit 1 and the control valves 41 to 43. At this time, an arithmetic processing program for calculating the component concentration from the characteristic value of the developing solution measured by the multivariate analysis method, so that the control amount (the characteristic value of the developing solution or the component concentration) becomes a predetermined control value, or If the control program that issues a control signal to the control valves 41 to 43 so as to be within a predetermined management area is installed in the computer, the developer can be maintained and managed in a predetermined state.

Other configurations, operations, etc. are similar to those of the eighteenth embodiment, and will be omitted.

[21st Embodiment]
FIG. 21 is a schematic diagram of a developing solution management device that manages two components of the developing solution. The developing solution management apparatus E of the present embodiment is preferably applied when controlling the concentration of the alkaline component and the concentration of the dissolved photoresist in the alkaline developing solution which is controlled so that the absorption of carbon dioxide is small.

The first measuring means 11 is a measuring means (for example, a conductivity meter for measuring conductivity) for measuring a characteristic value of the developer having a correlation with at least an alkali component concentration of the components of the developer, It is assumed that the measuring means 12 is a measuring means (for example, an absorptiometer for measuring an absorbance at a wavelength λ=560 nm) which measures at least the characteristic value of the developing solution which is correlated with at least the dissolved photoresist concentration among the components of the developing solution. For example, since the calculation unit 2 includes the calculation block 21 based on the multivariate analysis method, it is possible to calculate the alkaline component concentration and the dissolved photoresist concentration of the developer from the characteristic values of the developer measured by the multivariate analysis method.

Then, the control block 31 is a control block which issues a control signal to the control valve so that the electric conductivity or the alkali component concentration of the developing solution becomes a predetermined control value, and the control block 32 is a specific wavelength of the developing solution (for example, λ=560 nm). In the control block which issues a control signal to the control valve so that the absorbance or the dissolved photoresist concentration in) is within a predetermined control value or control region, the control unit 3 calculates the measured characteristic value of the developer. Since the measuring unit 1 and the arithmetic unit 2 are connected so as to be able to receive the component concentration of the developer, the developer managing device E of the present embodiment ensures that the concentration of the alkaline component of the developer becomes a predetermined control value. In addition, the developing solution can be maintained and controlled so that the dissolved photoresist concentration becomes a predetermined control value or within a control region.

The other details are the same as those of the other embodiments, and thus will be omitted.

[Twenty-second Embodiment]
FIG. 22 is a schematic diagram of a developing solution management device that manages two components of the developing solution based on the component concentrations. The developing solution management apparatus of the present embodiment is preferably applied when controlling the concentration of alkali components and the concentration of dissolved photoresist in an alkaline developing solution controlled so as not to absorb carbon dioxide to control concentration values.

The first measuring means 11 is a measuring means (for example, a conductivity meter for measuring conductivity) for measuring a characteristic value of the developer having a correlation with at least an alkali component concentration among the components of the developer, and the second measurement If the means 12 is a measuring means (for example, an absorptiometer for measuring the absorbance at λ=560 nm) for measuring the characteristic value of the developing solution which is correlated with at least the dissolved photoresist concentration among the components of the developing solution, the calculation is performed. Since the part 2 includes the calculation block 21 based on the multivariate analysis method, the alkali component concentration and the dissolved photoresist concentration of the developer can be calculated from the characteristic values of the developer measured by the multivariate analysis method.

Then, the control block 31 is a control block that issues a control signal to the control valve so that the alkali component concentration becomes a predetermined control value, and the control block 32 sets the dissolved photoresist concentration to a predetermined control value or below the control value. If it is a control block that issues a control signal to the control valve, since the control unit 3 is connected to the calculation unit 2 so as to receive the calculated component concentration of the developer, the developer management of the present embodiment is performed. With the apparatus E, the developer can be maintained and managed so that the concentration of the alkaline component of the developer becomes a predetermined control value and the concentration of the dissolved photoresist becomes a predetermined control value or a control value or less.

The other details are the same as those of the other embodiments, and thus will be omitted.

[Twenty-third embodiment]
FIG. 23 is a schematic diagram of a developing solution management device that manages two of the three components of the developing solution by characteristic values and the other one by component concentration. The developing solution management apparatus of the present embodiment manages the concentration of the alkaline component of the alkaline developing solution by the conductivity, the concentration of the dissolved photoresist by the absorbance at a specific wavelength (for example, λ=560 nm), and the concentration of the absorbed carbon dioxide by the concentration. It is preferably applied in some cases.

The first measuring means 11 is a measuring means (for example, a conductivity meter for measuring conductivity) for measuring a characteristic value of the developer having a correlation with at least an alkali component concentration of the components of the developer, The measuring means 12 is a measuring means (for example, an absorptiometer for measuring the absorbance at λ=560 nm) for measuring the characteristic value of the developing solution which is correlated with at least the dissolved photoresist concentration among the components of the developing solution. If the measuring means is a measuring means (for example, a densitometer for measuring density) that measures the characteristic value of the developing solution that has a correlation with at least the absorbed carbon dioxide concentration among the components of the developing solution, the computing unit 2 Since the calculation block 21 based on the multivariate analysis method is included, it is possible to calculate the alkali component concentration, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration of the developer from the characteristic values of the developer measured by the multivariate analysis method. ..

Then, the control block 31 is a control block that issues a control signal to the control valve so that the conductivity of the developer becomes a predetermined control value, and the control block 32 determines the absorbance at the characteristic wavelength of the developer (for example, λ=560 nm). It is a control block that issues a control signal to the control valve so that it falls within a predetermined control value or control region, and the control block 33 sends a control signal to the control valve so that the absorbed carbon dioxide concentration falls below a predetermined control value or control value. When it is a control block that emits, the control unit 3 is connected to the measurement unit 1 so as to receive the measured characteristic value of the developer, and the control unit 3 is connected so as to receive the calculated component concentration of the developer. Since it is connected, the developer management apparatus E of the present embodiment controls the concentration of the alkaline component of the developer to a predetermined control value and the dissolved photoresist concentration to a predetermined control value or a control value or less. The developer can be maintained and managed so that the absorbed carbon dioxide concentration becomes a predetermined control value or a control value or less.

The other details are the same as those of the other embodiments, and thus will be omitted.

[Twenty-fourth embodiment]
FIG. 24 is a schematic diagram of a developing solution management device that manages one of the three components of the developing solution by the characteristic value and the other two by the component concentration. The developing solution management apparatus of the present embodiment manages the concentration of the alkaline component and the absorbed carbon dioxide concentration of the alkaline developing solution based on the concentration, and the solution photoresist concentration based on the absorbance at a specific wavelength (for example, λ=560 nm). , Preferably applied.

The first measuring means 11 is a measuring means (for example, a conductivity meter for measuring conductivity) for measuring a characteristic value of the developer having a correlation with at least an alkali component concentration of the components of the developer, The measuring means 12 is a measuring means (for example, an absorptiometer for measuring the absorbance at λ=560 nm) for measuring the characteristic value of the developing solution which is correlated with at least the dissolved photoresist concentration among the components of the developing solution. If the measuring means is a measuring means (for example, a densitometer for measuring density) that measures at least the characteristic value of the developing solution that correlates with at least the absorbed carbon dioxide concentration among the components of the developing solution, then the computing unit 2 is often used. Since the calculation block 21 based on the variable analysis method is included, it is possible to calculate the alkaline component concentration of the developer, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration from the characteristic value of the developer measured by the multivariate analysis method.

Then, the control block 31 is a control block that issues a control signal to the control valve so that the concentration of the alkaline component becomes a predetermined control value, and the control block 32 sets the absorbance at the characteristic wavelength of the developer (for example, λ=560 nm) to a predetermined value. Is a control value for outputting a control signal to the control valve so that the control value is within the control value or the control area. The control block 33 sends a control signal to the control valve so that the absorbed carbon dioxide concentration becomes a predetermined control value or a control value or less. When the control block is issued, the control unit 3 is connected to the measuring unit 1 so as to receive the measured characteristic value of the developing solution, and is connected to the computing unit 2 so as to receive the calculated component concentration of the developing solution. Therefore, by the developing solution management device E of the present embodiment, the concentration of the alkaline component of the developing solution becomes a predetermined management value, and the dissolved photoresist concentration becomes a predetermined management value or a management value or less, Further, the developing solution can be maintained and controlled so that the absorbed carbon dioxide concentration becomes a predetermined control value or below the control value.

The other details are the same as those of the other embodiments, and thus will be omitted.

[Twenty-fifth embodiment]
FIG. 25 is a schematic diagram of a developing solution management device that manages the three components of the developing solution based on the component concentrations. The developing solution management apparatus of the present embodiment is preferably applied to the case where the concentration of the alkaline component of the alkaline developing solution, the concentration of the dissolved photoresist, and the concentration of absorbed carbon dioxide are controlled by the concentration.

The first measuring means 11 is a measuring means (for example, a conductivity meter for measuring conductivity) for measuring a characteristic value of the developer having a correlation with at least an alkali component concentration among the components of the developer, and the second measurement The means 12 is a measuring means (for example, an absorptiometer for measuring the absorbance at λ=560 nm) for measuring the characteristic value of the developer having a correlation with at least the dissolved photoresist concentration among the components of the developer, and the third measurement If the means is a measuring means (for example, a densitometer for measuring the density) that measures the characteristic value of the developer having a correlation with at least the absorbed carbon dioxide concentration among the components of the developer, the computing unit 2 performs the multivariate analysis. Since the calculation block 21 based on the method is included, it is possible to calculate the alkali component concentration, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration of the developer from the characteristic values of the developer measured by the multivariate analysis method.

Then, the control block 31 is a control block that issues a control signal to the control valve so that the alkali component concentration becomes a predetermined management value, and the control block 32 makes the container photoresist concentration become a predetermined management value or a management value or less. When the control block 33 is a control block which issues a control signal to the control valve and the control block 33 issues a control signal to the control valve so that the absorbed carbon dioxide concentration becomes a predetermined control value or a control value or less, the control unit 3 Is connected to the calculation unit 2 so that the calculated component concentration of the developing solution can be received, so that the developing solution management apparatus E of the present embodiment sets the alkaline component concentration of the developing solution to a predetermined management value. The developing solution can be maintained and managed so that the dissolved photoresist concentration becomes a predetermined control value or a control value or less and the absorbed carbon dioxide concentration becomes a predetermined control value or a control value or less.

The other details are the same as those of the other embodiments, and thus will be omitted.

As described above, as shown in the eighteenth to twenty-fifth embodiments, the developing solution management apparatus of the present embodiment is a measuring unit that measures a plurality of characteristic values of the developing solution that are correlated with the component concentration of the alkaline developing solution. 1 and a calculation unit 2 for calculating the component concentration of the developer by the multivariate analysis method from a plurality of characteristic values measured by the measurement unit 1, and the characteristic value of the developer measured by the measurement unit 1 or the calculation unit 2. And a control unit 3 for issuing a control signal to the control valves 41 to 43 provided in the flow path for feeding a replenisher solution to be replenished to the developer solution based on the calculated component concentration of the developer solution.

The measuring unit 1 and the calculating unit 2 in the developing solution management apparatus according to the present embodiment can take various modes, like the measuring unit 1 and the calculating unit 2 in the developer concentration measuring apparatus.

The control unit 3 in the developing solution management apparatus of the present embodiment does not need to be provided as a device separate from the calculation unit 2, and may be implemented as a control function and a calculation function of an integrated device (for example, a computer). Good. Further, as shown in FIG. 11, the control unit 3 may be configured separately from the measurement unit 1 and the calculation unit 2. The control unit 3 mutually communicates with the measurement unit 1 and the calculation unit 2 so that the control unit 3 can receive the characteristic value measured by the measurement unit 1 or the component concentration calculated by the calculation unit 2. It should be. Then, the required control signal can be issued based on the received characteristic value and component concentration.

The pipeline for feeding the replenisher may or may not be connected to the developing solution management device E of this embodiment. The control valve also need not be an internal component of the developer management apparatus E. It may be provided outside the developer management apparatus E as long as it is in communication with the control unit 3 so as to be controlled by the control signal of the control unit 3.

As described above, according to the developing solution management apparatus of the present invention, each component concentration or each characteristic value of the developing solution can be managed within a predetermined management value or management range. Therefore, with the developing solution management apparatus of the present invention, it is possible to maintain the optimum developing performance and realize a desired line width and residual film thickness.

According to the developing solution management apparatus of the present invention, since the concentration of each component of the developing solution is accurately controlled to a predetermined state, it is possible to maintain and manage the developing performance of the developing solution so as to be more accurately constant. Therefore, the development speed at the time of developing the photoresist is constantly stabilized, the line width and the remaining film thickness due to the development processing are made constant, the product quality is improved, and further miniaturization and high integration are realized. Is expected to contribute to.

According to the developing solution management apparatus of the present invention, the developing solution is automatically and constantly maintained at the optimum developing performance, so that the product yield is improved, and the replacement work of the developing solution is unnecessary, and the running cost and the waste solution cost are reduced. Is expected to contribute to.

A... Component concentration measuring device, B... Development process equipment, C... Replenisher storage part, D... Circulating stirring mechanism, E... Developer management device 1... Measuring part 11... First measuring means, 12... Second measurement Means, 13... third measuring means,
11a, 12a, 13a... Measuring device main body, 11b, 12b, 13b... Measuring probe 14, 14a, 14b, 14c... Sampling pump, 15, 15a, 15b, 15c... Sampling piping, 16, 16a, 16b, 16c... Return piping , 17... Liquid feed pump, 18... Liquid feed pipe, 19... Waste liquid pipe 2... Calculation part 21... Multivariate analysis method calculation block, 22... Calibration curve method calculation block,
3... Control unit 31, 32, 33... Control block 23... Calculation control unit (for example, computer)
4... Valves 41-43... Control valves, 44, 45... Valves, 46, 47... Pressurized gas valve 5... Signal lines 51-53... Measurement data signal lines 54... Calculation data signal lines 55-57 ... Control signal signal line 6... Development equipment 61... Developer storage tank, 62... Overflow tank, 63... Liquid level gauge, 64... Development chamber hood, 65... Roller conveyor, 66... Substrate, 67... Developer shower nozzle 7 ...Development equipment 71...Waste liquid pump, 72,74... Circulation pump, 73,75... Filter 8...Fluid conduit 80...Developer conduit, 81,82...Replenisher (development stock solution and/or new solution) tube Channels, 83... Pure water pipelines, 84... Combined pipelines, 85... Circulation pipelines, 86... Nitrogen gas pipelines 9... Replenisher storage tanks, etc. 91, 92... Replenisher (development stock solution and/or New liquid) Storage tank 93... Additive reagent

Claims (10)

Repeatedly used, a step of measuring a plurality of characteristic values of the developer having a correlation with the component concentration of the developer exhibiting alkalinity,
Based on the measured plurality of characteristic values, by a multivariate analysis method, a step of calculating the component concentration of the developer,
And a method for measuring the component concentration of a developer containing. Repeatedly used, a measuring unit for measuring a plurality of characteristic values of the developer having a correlation with the component concentration of the developer exhibiting alkalinity,
Based on the plurality of characteristic values measured by the measurement unit, by a multivariate analysis method, a calculation unit for calculating the component concentration of the developer,
An apparatus for measuring the component concentration of a developing solution. Repeatedly used, a step of measuring a plurality of characteristic values of the developer having a correlation with the component concentration of the developer exhibiting alkalinity,
From the measured characteristic values, by a multivariate analysis method, a step of calculating the component concentration of the developer,
Based on a measured value or a calculated value of a managed item selected from a plurality of characteristic values of the developing solution measured in the measuring step and component concentrations of the developing solution calculated in the calculating step, Replenishing the developer with a replenisher,
A method for managing a developer including:. Repeatedly used, a measuring unit for measuring a plurality of characteristic values of the developer having a correlation with the component concentration of the developer exhibiting alkalinity,
Based on the plurality of characteristic values measured by the measuring unit, by a multivariate analysis method, a calculation unit for calculating the component concentration of the developer,
Based on a measured value or a calculated value of a managed item selected from a plurality of characteristic values of the developing solution measured by the measuring section and a component concentration of the developing solution calculated by the computing section, A control unit for issuing a control signal to a control valve provided in a flow path for supplying a replenishing liquid to be replenished to the liquid,
A developing solution management device. The measurement unit,
First measuring means for measuring a characteristic value of the developer having a correlation with the concentration of at least an alkaline component among the components of the developer,
Second measuring means for measuring the characteristic value of the developer having a correlation with the concentration of the photoresist dissolved in the developer at least among the components of the developer,
The developer management device according to claim 4, further comprising: The calculation unit includes a calculation block for calculating the concentration of the alkaline component of the developer and the concentration of the photoresist,
The control unit,
A control block that issues a control signal to the control valve so that the concentration of the alkaline component calculated by the calculation block becomes a predetermined control value;
A control block for issuing a control signal to the control valve so that the concentration of the photoresist calculated by the calculation block is equal to or less than a predetermined control value;
The developing solution management apparatus according to claim 5, further comprising: The measuring unit is further third measuring means for measuring a characteristic value of the developer at least the correlated with the concentration of the absorbed carbon dioxide in the developing solution of the components of the developer, Ru with the invoiced Item 6. The developer management device according to Item 5. The calculation unit includes a calculation block for calculating the concentration of carbon dioxide of the developer,
The control unit,
A control block for issuing a control signal to the control valve so that the characteristic value of the developer measured by the first measuring means becomes a predetermined control value;
A control block for issuing a control signal to the control valve so that the characteristic value of the developing solution measured by the second measuring means falls within a predetermined management region;
A control block that issues a control signal to the control valve so that the concentration of carbon dioxide calculated by the calculation block is equal to or less than a predetermined control value,
The developer management device according to claim 7, further comprising: The arithmetic unit includes an arithmetic block for calculating the concentration of the alkaline component and the concentration of carbon dioxide of the developer,
The control unit,
A control block that issues a control signal to the control valve so that the concentration of the alkaline component calculated by the calculation block becomes a predetermined control value;
A control block for issuing a control signal to the control valve so that the characteristic value of the developing solution measured by the second measuring means falls within a predetermined management region;
A control block that issues a control signal to the control valve so that the concentration of carbon dioxide calculated by the calculation block is equal to or less than a predetermined control value,
The developer management device according to claim 7, further comprising: The calculation unit includes a calculation block for calculating the concentration of the alkaline component of the developer, the concentration of the photoresist, and the concentration of carbon dioxide,
The control unit,
A control block that issues a control signal to the control valve so that the concentration of the alkaline component calculated by the calculation block becomes a predetermined control value;
A control block that issues a control signal to the control valve so that the concentration of the photoresist calculated by the calculation block is equal to or less than a predetermined control value;
A control block that issues a control signal to the control valve so that the concentration of carbon dioxide calculated by the calculation block is equal to or less than a predetermined control value,
The developer management device according to claim 7, further comprising:

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