JP2018120899A - Developer management device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer management device that can maintain desired developer performance and achieve a development process capable of maintaining a desired line width and a residual film thickness.SOLUTION: A developer management device D includes: control means 21 including a data memory 23 storing conductivity data having conductivity values of a developer that is repeatedly used and shows alkalinity and that is preliminarily confirmed to have predetermined development performances in each concentration region specified by the concentration of a dissolved photoresist and the concentration of absorbed carbon dioxide as indices in the developer, and a control part 31 transmitting a control signal to a control valve disposed in a pipeline where a replenisher for replenishing the developer is fed so as to control the conductivity of the developer to a control target value depending on a measurement value of the concentration of the dissolved photoresist and a measurement value of the concentration of absorbed carbon dioxide in the developer; and display means 22 for displaying at least either a conductivity value or an alkali component concentration value in the conductivity value, alkali component concentration value, dissolved photoresist concentration value and absorbed carbon dioxide concentration value of the developer.SELECTED DRAWING: Figure 1

Description

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

  In the development process of photolithography that realizes fine wiring processing in a semiconductor, a liquid crystal panel, etc., as a chemical solution that dissolves the photoresist formed on the substrate, an alkaline developer (hereinafter referred to as “alkaline developer”) is used. .) Is used.

  In the manufacturing process of semiconductors and liquid crystal panel substrates, in recent years, the enlargement of wafers and glass substrates and the miniaturization and high integration of wiring processing have been promoted. Under such circumstances, it is necessary to measure and maintain the developer by measuring the concentration of the main component of the alkaline developer with higher accuracy in order to realize the miniaturization and high integration of the wiring processing of the large substrate. It has become to.

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

  However, in recent years, the development process has increased the chance that the alkaline developer comes into contact with air, and the alkaline developer absorbs carbon dioxide in the air, so the amount of carbon dioxide absorbed by the alkaline developer has increased. When the absorbed carbon dioxide concentration becomes high, there is a problem that the predetermined line width processing cannot be maintained in the conventional developer management.

  This problem occurs because an alkaline component having development activity in an alkaline developer is consumed in a reaction that produces carbonate by absorption of carbon dioxide. Further, this occurs because an alkali component having development activity in an alkaline developer is also consumed by a reaction that generates a photoresist salt due to dissolution of the photoresist.

  In order to solve such problems, various attempts have been made to manage the developing solution to compensate for the reduced alkaline component. In these attempts, the concentration of the alkali component having development activity is made constant by compensating for the alkali component consumed in the reaction for producing the carbonate by a replenisher by measuring the carbonate concentration. The same applies to the alkali component consumed by dissolution of the photoresist. These are based on the viewpoint that the alkali component that has become carbonate or photoresist salt loses development activity and is deactivated (for example, Patent Document 2).

Japanese Patent No. 2561578 JP 2008-283162 A

  However, even with such various developer management attempts, it has still been difficult to achieve satisfactory developer management.

  As a result of intensive research on the management of the developer, the present inventors have found that carbonates and resist salts are partly liberated in the developer and contribute to the developing action, and from these components that were supposed to be deactivated. The developer management that takes into account the contribution to the development action of the developer can be realized by managing the conductivity value of the developer. Furthermore, the conductivity management values include the absorbed carbon dioxide concentration and the dissolved photoresist concentration. I got the knowledge that it is different in various ways.

  This is because the alkali component that became carbonate or photoresist salt was not deactivated, but partly liberated and contributed to the developing action, and from the alkali component, carbonate and resist salt having development activity It seems that this is based on the fact that any component that liberates and contributes to the developing action acts on the conductivity. That is, the inventor found out that the total of the components having a developing action is optimally managed by controlling the conductivity value of the developer, and the present invention has been achieved.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a developer management apparatus capable of achieving a predetermined development performance for a photoresist.

  In order to achieve the above object, the developer management apparatus of the present invention provides a predetermined development for each concentration region that is repeatedly used and is specified using the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer exhibiting alkalinity as an index. A data storage unit storing conductivity data having conductivity values of the developer that have been confirmed in advance to be performance, a measured value of dissolved photoresist concentration and a measured value of absorbed carbon dioxide concentration of the developer A replenisher that is replenished to the developer so that the conductivity of the developer becomes the control target value, with the conductivity value stored in the data storage unit in the concentration region specified by A control unit that emits a control signal to a control valve provided in a conduit for supplying the liquid, and a conductivity value, an alkali component concentration value, and a dissolved photoresist concentration of the developer. And a display means for displaying either one of at least conductivity values and alkaline component concentration value of the absorbing carbon dioxide concentration value.

  The developer management apparatus of the present invention preferably further comprises display switching means for switching a display target displayed on the display means.

  The developer management apparatus of the present invention has been confirmed in advance to have a predetermined development performance for each concentration region that is repeatedly used and is specified using the dissolved photoresist concentration and absorbed carbon dioxide concentration of the developer exhibiting alkalinity as an index. A data storage unit storing conductivity data having conductivity values of the developer, and the concentration region specified by the measured value of the dissolved photoresist concentration and the measured value of absorbed carbon dioxide concentration of the developer. Provided in a conduit for supplying a replenisher to be replenished to the developer so that the conductivity of the developer becomes the control target value with the conductivity value stored in the data storage unit as the control target value. A control unit that issues a control signal to the control valve, and a conductivity value, an alkali component concentration value, a dissolved photoresist concentration value, and an absorbed carbon dioxide concentration value of the developer. Among one of the at least conductivity values and alkaline component concentration value, comprising display means for displaying the graph in the indicator the time elapsed from the measurement time or the measurement start, the.

  The developer management apparatus of the present invention preferably further comprises display switching means for switching a display target displayed on the display means.

  According to the developer management apparatus of the present invention, no matter what dissolved photoresist concentration and absorbed carbon dioxide concentration the developer has, the active component in the developing action in the developer is maintained constant. A desired development performance can be maintained, and a development process capable of maintaining a desired line width and remaining film thickness can be realized. Various data and graphs can be displayed.

  According to a preferred aspect of the developer management apparatus of the present invention, the developer characteristic value correlated with the dissolved photoresist concentration of the developer solution and the developer characteristic correlated with the absorbed carbon dioxide concentration of the developer solution. A plurality of measuring devices that measure a plurality of characteristic values of the developer including a value, and the control unit further includes a plurality of characteristic values of the developer measured by the plurality of measuring devices, An arithmetic unit that calculates a measured value of the dissolved photoresist concentration and a measured value of the absorbed carbon dioxide concentration of the developer by a multivariate analysis method.

  According to a preferred aspect of the developer management apparatus of the present invention, the developer characteristic value correlated with the dissolved photoresist concentration of the developer solution and the developer characteristic correlated with the absorbed carbon dioxide concentration of the developer solution. A plurality of measuring devices for measuring a plurality of characteristic values of the developer including a value, and a plurality of characteristic values of the developer measured by the plurality of measuring devices, using a multivariate analysis method. And a calculation means for calculating a measured value of the dissolved photoresist concentration of the liquid and a measured value of the absorbed carbon dioxide concentration.

  According to a preferred aspect of the developer management apparatus of the present invention, a density meter is provided, and the control unit further measures by the density meter based on the correspondence relationship between the absorbed carbon dioxide concentration and the density of the developer. An arithmetic unit that calculates an absorbed carbon dioxide concentration value of the developer from the density value of the developer.

  According to a preferred aspect of the developer management apparatus of the present invention, the density value of the developer measured by the density meter based on the correspondence between the density meter and the absorbed carbon dioxide concentration and density of the developer. And calculating means for calculating an absorbed carbon dioxide concentration value of the developer.

  According to the developer management apparatus of the present invention, predetermined development performance is determined for each concentration region that is repeatedly used, and is specified with the absorbance and the absorbed carbon dioxide concentration being correlated with the dissolved photoresist concentration of the developer exhibiting alkalinity. A data storage unit storing alkali component concentration data having an alkali component concentration value of the developer that has been confirmed in advance, and a concentration specified by measured values of the absorbance and absorbed carbon dioxide concentration of the developer Using the alkali component concentration value stored in the data storage unit in the area as a control target value, the replenisher to be replenished to the developer is sent so that the alkali component concentration of the developer becomes the control target value. A control unit that issues a control signal to a control valve provided in the pipe, and an alkali component concentration value of the developer, a concentration of the dissolved photoresist Absorbance values correlated with, and, and a display means for displaying at least the alkaline component concentration value of the absorbing carbon dioxide concentration value.

  According to the developer management apparatus of the present invention, predetermined development performance is determined for each concentration region that is repeatedly used, and is specified with the absorbance and the absorbed carbon dioxide concentration being correlated with the dissolved photoresist concentration of the developer exhibiting alkalinity. A data storage unit storing alkali component concentration data having an alkali component concentration value of the developer that has been confirmed in advance, and a concentration specified by measured values of the absorbance and absorbed carbon dioxide concentration of the developer Using the alkali component concentration value stored in the data storage unit in the area as a control target value, the replenisher to be replenished to the developer is sent so that the alkali component concentration of the developer becomes the control target value. A control unit that issues a control signal to a control valve provided in the pipe, and an alkali component concentration value of the developer, a concentration of the dissolved photoresist Absorbance values correlated with, and, and a display means for displaying graphically at least the alkaline component concentration value, as an index, the elapsed time from the measurement time or the measurement start of the absorption of carbon dioxide concentration value.

  According to the developer management apparatus of the present invention, it is preferable to further include a display switching unit that switches a display target displayed on the display unit.

  According to the present invention, no matter what dissolved photoresist concentration or absorbed carbon dioxide concentration the developer has, the component having activity in the developing action in the developer is kept constant, so that the desired development performance can be obtained. Development processing that can maintain the desired line width and remaining film thickness can be realized. Various data and graphs can be displayed.

It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 1st embodiment. It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 2nd embodiment. It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 3rd embodiment. It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 4th embodiment. It is a graph which shows the relationship between the absorbed carbon dioxide density | concentration of a developing solution, and a density. It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 5th embodiment. It is a schematic diagram of the image development process for demonstrating the developing solution management apparatus of 6th embodiment.

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

  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 developer to which the present invention is applied is not limited to this. Examples of other developing solutions to which the developing solution management method and apparatus of the present invention can be applied include aqueous solutions of inorganic compounds such as potassium hydroxide, sodium hydroxide, sodium phosphate, sodium silicate, and trimethylmonoethanol ammonium hydroxide. An aqueous solution of an organic compound such as (choline) can be mentioned.

  In the following description, component concentrations such as alkali component concentration, dissolved photoresist concentration, and absorbed carbon dioxide concentration are concentrations based on weight percentage concentration (wt%). “Dissolved photoresist concentration” refers to the concentration when the dissolved photoresist is converted as the amount of photoresist, and “absorbed carbon dioxide concentration” refers to when the absorbed carbon dioxide is converted as the amount of carbon dioxide. The concentration of

  In the development process, development is performed by the developer dissolving unnecessary portions of the photoresist film after the exposure process. The photoresist dissolved in the developer generates a photoresist salt with the alkali component of the developer. For this reason, unless the developer is appropriately managed, as the development process proceeds, the developer deteriorates due to consumption of an alkaline component having development activity, and the development performance deteriorates. At the same time, the dissolved photoresist is accumulated in the developer as a photoresist salt with an alkali component.

  The photoresist dissolved in the developer exhibits a surface activity in the developer. For this reason, the photoresist dissolved in the developer improves the wettability of the photoresist film subjected to the development process with respect to the developer and improves the familiarity between the developer and the photoresist film. Therefore, with a developer containing a moderate amount of photoresist, the developer spreads well in fine concave portions of the photoresist film, and the development processing of the photoresist film having fine irregularities can be performed satisfactorily.

  Further, in recent development processing, with the increase in the size of the substrate, a large amount of the developer has been repeatedly used, so that the opportunity for the developer to be exposed to air is increasing. However, alkaline developers absorb carbon dioxide in the air when exposed to air. The absorbed carbon dioxide forms carbonate with the alkali component of the developer. For this reason, if the developer is not properly managed, the developer is consumed and reduced by the carbon dioxide in which the alkali component having development activity is absorbed. At the same time, the absorbed carbon dioxide is accumulated in the developer as a carbonate with an alkali component.

  However, the carbonate in the developer has a developing action because it shows alkalinity in the developer.

  Thus, unlike the conventional recognition that the photoresist dissolved in the developer and the absorbed carbon dioxide inactivate the development activity of the development process, it actually contributes to the development performance of the developer. Yes. Therefore, instead of managing the developer so as to completely eliminate dissolved photoresist and absorbed carbon dioxide, it is possible to dissolve these dissolved photoresist and absorbed carbon dioxide in the developer while maintaining the optimum concentration. Therefore, it is necessary to manage the developer to maintain the current.

  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. These free ions affect the conductivity of the developer with various contributions.

  With regard to these points, the present inventor has conducted extensive research on developer management, and it is believed that some of the carbonates and resist salts are liberated in the developer and contribute to the developing action, and are deactivated. In addition, the developer management considering the contribution to the developing action from these components can be realized by managing the conductivity value of the developer. And the fact that it is different depending on the concentration of dissolved photoresist.

  Accordingly, the inventor assumes that the TMAH aqueous solution is managed as a developer, and variously changes the dissolved photoresist concentration and the absorbed carbon dioxide concentration to change the desired development performance for the photoresist and the conductivity of the developer. The relationship with the value was obtained.

  The absorbed carbon dioxide concentration is changed between 0.0 and 1.3 (wt%), and the dissolved photoresist concentration is changed to 0.0 to 0.40 (wt%) (equivalent to 0.0 to 1.3 (abs)). The sample of the developer of the aqueous solution of TMAH changed between the above was prepared. The inventor measured the developer conductivity, absorbed carbon dioxide concentration, and dissolved photoresist concentration for these samples to determine the development performance, conductivity, absorbed carbon dioxide concentration, and dissolved photoresist concentration components. An experiment was conducted to confirm the correlation. A matrix (combination table) was created in which the absorbed carbon dioxide concentration was arranged as one item vertically or horizontally, and the dissolved photoresist concentration was taken as another item, and arranged horizontally or vertically. For each combination of absorbed carbon dioxide concentration and dissolved photoresist concentration, the conductivity of the developer that satisfies the desired development performance for the photoresist was determined and entered in each column to complete the matrix.

  Here, the predetermined development performance means the development performance of the developer when the line width or the remaining film thickness to be realized in the development process is realized.

  The measurement results of the absorbed carbon dioxide concentration, dissolved photoresist concentration, and conductivity of each representative sample are illustrated. When the absorbed carbon dioxide concentration is 0.0 (wt%) and the dissolved photoresist concentration is 0.0 (wt%) (equivalent to 0.0 (abs)) (so-called new solution), the predetermined development performance is exhibited. The conductivity of the developer which can be produced was 54.58 (mS / cm).

  When the absorbed carbon dioxide concentration is 0.0 (wt%) and the dissolved photoresist concentration is 0.25 (wt%) (equivalent to 0.8 abs), the conductivity of the developer capable of exhibiting a predetermined developing performance is 54. When the dissolved photoresist concentration was 0.40 (wt%) (corresponding to 1.3 abs), the developer conductivity was 54.53 (mS / cm).

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

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

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

  In the above-described experiment, the conductivity management value tends to increase as the absorbed carbon dioxide concentration increases in a certain concentration range, and the conductivity management value tends to decrease as the dissolved photoresist concentration increases. It was observed.

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

  The above-described conductivity, absorbed carbon dioxide concentration, and dissolved photoresist concentration are for finding the relationship between the conductivity, absorbed carbon dioxide concentration, dissolved photoresist concentration, and development performance, and are not limited to each numerical value. .

  As described above, it can be understood that the conductivity at which the development performance can be exhibited varies depending on the absorbed carbon dioxide concentration and the dissolved photoresist concentration. Thus, in the management of the developer, in the developer containing the absorbed carbon dioxide and the dissolved photoresist, the conductivity is set as the management value, and the absorbed carbon dioxide concentration and the dissolved photoresist concentration are further measured. The predetermined development performance can be exhibited by changing the management value of the conductivity based on this.

  In other words, conductivity data having a conductivity value of the developer that has been confirmed in advance to have a predetermined development performance for each concentration region specified by using the dissolved photoresist concentration of the developer and the absorbed carbon dioxide concentration as an index. By storing the matrix) and using the conductivity data (matrix), it is possible to manage the developer that can exhibit a predetermined development performance.

  In addition, when the inventor diligently studied the management of the developer, the carbonate and resist salts were partly released in the developer and contributed to the developing action, and these components that were thought to be deactivated The developer management considering the contribution to the developing action from the above can be realized by managing the alkali component concentration value of the developer. Further, the control value of such alkali component concentration is the absorbed carbon dioxide concentration and dissolution We obtained the knowledge that there were various differences depending on the absorbance correlated with the photoresist concentration.

  Therefore, the inventor assumed that the TMAH aqueous solution is managed as a developer, and the correlation between the alkali component concentration measured based on the conductivity of the developer exhibiting alkalinity and the dissolved photoresist concentration of the developer. Various changes were made in the absorbance and the absorbed carbon dioxide concentration of the developer, and the relationship between the desired development performance for the photoresist and the alkali component concentration of the developer was determined.

  TMAH in which the absorbed carbon dioxide concentration was changed between 0.0 and 1.3 (wt%), and the absorbance correlated with the dissolved photoresist concentration was changed between 0.0 and 1.3 (abs). An aqueous developer sample was prepared. The inventor measured the alkali component concentration, absorbed carbon dioxide concentration, and absorbance of these samples, and conducted an experiment to confirm the correlation with the development performance, alkali component concentration, absorbed carbon dioxide concentration, and absorbance. went. A matrix (combination table) was prepared in which the absorbed carbon dioxide concentration was arranged as one item vertically or horizontally, and the absorbance was set as another item, and arranged horizontally or vertically. For each combination of absorbed carbon dioxide concentration and absorbance, the alkali component concentration of the developer that satisfies the desired development performance for the photoresist was determined and entered in each column to complete the matrix.

  Here, the predetermined development performance means the development performance of the developer when the line width or the remaining film thickness to be realized in the development process is realized.

  The measurement results of the absorbed carbon dioxide concentration, absorbance, and alkali component concentration of each representative sample are illustrated. When the absorbed carbon dioxide concentration is 0.0 (wt%) and the absorbance is 0.0 (abs) (so-called new solution), the alkali component concentration of the developer capable of exhibiting a predetermined development performance is 2.380 (wt). %)Met.

  When the absorbed carbon dioxide concentration is 0.0 (wt%) and the absorbance is 0.8 abs, the alkali component concentration of the developer capable of exhibiting a predetermined development performance is 2.379 (wt%), and the absorbance is 1 In the case of .3 abs, the alkali component concentration of the developer was 2.378 (wt%).

  When the absorbance is 0.0 (abs) and the absorbed carbon dioxide concentration is 0.6 (wt%), the alkali component concentration of the developer is 2.381 (wt%), and the absorbed carbon dioxide concentration is In the case of 1.3 (wt%), the alkali component concentration of the developer was 2.388 (wt%).

  When the absorbed carbon dioxide concentration is 0.6 (wt%) and the absorbance is 0.7 abs, the alkali component concentration of the developer is 2.381 (wt%) and the absorbance is 1.3 abs. The alkali component concentration of the developer was 2.380 (wt%).

  Further, when the absorbed carbon dioxide concentration is 1.3 (wt%) and the absorbance is 0.7 abs, the alkali component concentration of the developer is 2.388 (wt%) and the absorbance is 1.3 abs. The alkali component concentration of the developer was 2.388 (wt%).

  In the above-described experiment, when the absorbed carbon dioxide concentration increases in a certain concentration region, the management value of the alkali component concentration tends to increase, and when the absorbance increases, the management value of the alkali component concentration tends to decrease. It was seen.

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

  The value measured by the titration analysis method was used for the absorbed carbon dioxide concentration. Titration is neutralization titration using hydrochloric acid as a titration reagent. As a titration apparatus, an automatic titration apparatus GT-200 manufactured by Mitsubishi Chemical Analytech Co., Ltd. was used. An absorptiometer was used to measure the absorbance.

  The alkali component concentration, the absorbed carbon dioxide concentration, and the absorbance described above are for finding the alkali component concentration, the absorbed carbon dioxide concentration, and the relationship between the absorbance and the development performance, and are not limited to the respective numerical values.

  As described above, it can be understood that the alkali component concentration capable of exhibiting the development performance varies depending on the absorbed carbon dioxide concentration and the absorbance. Thus, in the management of the developer, in the developer containing the absorbed carbon dioxide and the dissolved photoresist, the alkali component concentration is set as the control value of the developer, and the absorbed carbon dioxide concentration and the absorbance are measured, and each measurement result By varying the control value of the alkali component concentration based on the above, predetermined development performance can be exhibited.

  That is, alkali component concentration data (matrix) having an alkali component concentration value of the developer that has been confirmed in advance to have a predetermined developing performance for each concentration region specified by using the absorbance of the developer and the absorbed carbon dioxide concentration as an index. ) And the use of the alkali component concentration data (matrix), the predetermined development performance can be exhibited.

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

[First embodiment]
FIG. 1 is a schematic diagram of a developing process for explaining the developer management apparatus D of the present embodiment. A developing solution management apparatus D of the present invention is shown together with a developing process facility A, a replenisher storing portion B, a circulation stirring mechanism C, and the like.

  First, the development process facility A will be briefly described.

  The development process facility A mainly includes a developer storage tank 61, an overflow tank 62, a development chamber hood 64, a roller conveyor 65, a developer shower nozzle 67, and the like. A developer is stored in the developer storage tank 61. The composition of the developer is managed by replenishing the replenisher. The developer storage tank 61 includes a liquid level gauge 63 and an overflow tank 62, and manages an increase in the amount of liquid caused by replenishing the replenisher. The developer reservoir 61 and the developer shower nozzle 67 are connected by a developer conduit 80. The developer stored in the developer storage tank 61 is sent to the developer shower nozzle 67 via the filter 73 by a circulation pump 72 provided in the developer conduit 80. The roller conveyor 65 is provided above the developer storage tank 61 and conveys a substrate 66 on which a photoresist film is formed. The developer is dropped from the developer shower nozzle 67. The substrate 66 conveyed by the roller conveyor 65 is immersed in the developer by passing through the dropped developer. Thereafter, the developer is collected in the developer storage tank 61 and stored again. As described above, the developer is circulated and used repeatedly in the development process. Note that the developing chamber in a small glass substrate may be subjected to a treatment that does not absorb carbon dioxide in the air, for example, by being filled with nitrogen gas. The deteriorated developer is drained (drained) by operating the waste liquid pump 71.

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

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

  Further, when the replenisher flows into the circulation line 85 via the junction line 84, the replenisher that has flowed into the developer storage tank 61 is mixed with the developer circulating in the circulation line 85. Supplied.

  Next, the developer management apparatus D of this embodiment will be described. The developer management apparatus D of the present embodiment is a developer that has been confirmed in advance to have a predetermined development performance for each concentration region specified by using the dissolved photoresist concentration and absorbed carbon dioxide concentration of the developer exhibiting alkalinity as an index. Using the conductivity data having the conductivity value of the developer, the measured value of the dissolved photoresist concentration of the developer and the conductivity of the concentration region specified by the measured value of the absorbed carbon dioxide concentration are used as control target values. This is a developing solution management apparatus that replenishes the developing solution with a replenisher so that the conductivity becomes a control target value.

  The developer management apparatus D includes a measuring unit 1 and a control unit 21. The developer management apparatus D is connected to the developer storage tank 61 by a sampling pipe 15 and an outlet side pipe 16.

  The measuring unit 1 includes a sampling pump 14, a conductivity meter 11, a first concentration measuring means 12 for measuring the dissolved photoresist concentration, and a second concentration measuring means 13 for measuring the absorbed carbon dioxide concentration. Yes. The conductivity meter 11, the first concentration measuring unit 12, and the second concentration measuring unit 13 are connected in series to the subsequent stage of the sampling pump 14. The measurement unit 1 preferably further includes a temperature adjusting means (not shown) that stabilizes the sampled developer at a predetermined temperature in order to increase the measurement accuracy. At this time, the temperature adjusting means is preferably provided immediately before the measuring means. The sampling pipe 15 is connected to the sampling pump 14 of the measuring unit 1 of the developer management device D, and the outlet side pipe 16 is connected to a pipe at the end of the measuring means.

  In FIG. 1, the conductivity meter 11, the first concentration measuring unit 12, and the second concentration measuring unit 13 are illustrated as being connected in series, but the conductivity meter 11, the first concentration measuring unit 12, And the connection of the 2nd density | concentration measurement means 13 is not limited to this. A parallel connection may be used, or each may be independently provided with a liquid supply path for measurement. The order of the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 is not particularly limited. What is necessary is just to measure in the optimal order suitably according to the characteristic of each measuring means.

  The control means 21 includes a data storage unit 23 and a control unit 31. In the data storage unit 23, it is confirmed in advance that a predetermined development performance is obtained for each concentration region specified by using the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer exhibiting alkalinity as an index. Conductivity data having conductivity values is stored.

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

  The control unit 31 of the control means 21 is connected to control valves 41 to 43 provided in a pipeline for sending the replenisher to the developer by a signal line. In FIG. 1, the control valves 41 to 43 are illustrated as internal components of the developer management device D, but the control valves 41 to 43 are not necessarily essential components of the developer management device D of the present embodiment. . The control unit 31 only needs to communicate with the control valves 41 to 43 so as to control the operation of the control valves 41 to 43 so that the replenisher can be supplied to the developer. The control valves 41 to 43 may exist outside the developer management apparatus D.

  The developer management apparatus D of the embodiment further includes a display unit 22. The display means 22 may display at least one of the conductivity value and the alkali component concentration value among the conductivity value, the alkali component concentration value, the dissolved photoresist concentration value, and the absorbed carbon dioxide concentration value of the developer. it can.

  The display means 22 may be a display monitor electrically connected to the developer management apparatus D or a touch panel computer incorporated in the developer management apparatus D. In the case of a touch panel computer, a control unit and a display unit (a control unit and a data storage unit) are integrally configured.

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

  The developer sampled from the developer reservoir 61 is fed into the measuring unit 1 and the temperature is adjusted. Thereafter, the developer is fed to the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13, and the conductivity, dissolved photoresist concentration, and absorbed carbon dioxide concentration are measured. Each measurement data is sent to the control means 21.

  The control unit 31 has a conductivity having a conductivity value of the developer that has been confirmed in advance to have a predetermined development performance for each concentration region specified by using the dissolved photoresist concentration and the absorbed carbon dioxide concentration as an index. A conductivity management value corresponding to the conductivity value of the data is set. The control unit 31 performs control as follows based on the measurement data received from the measurement unit 1.

  Based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration received from the measuring unit 1, the control unit 31 measures and measures the measured dissolved photoresist concentration in the conductivity data stored in the data storage unit 23. The conductivity value in the concentration region specified by the absorbed carbon dioxide concentration is obtained. The obtained conductivity value is set as a control target value for the conductivity of the developer.

  The control unit 31 compares the measured conductivity received from the measurement unit 1 with the conductivity set as the control target value, and performs the following management according to the comparison result. That is, when the conductivity set as the control target value is the same as the measured conductivity, basically, no replenisher is added to the developer. When the conductivity set as the control target value is larger than the measured conductivity, a replenisher that acts to increase the conductivity may be supplied to the developer. When the conductivity set as the control target value is smaller than the measured conductivity, a replenisher that acts to lower the conductivity may be supplied to the developer.

  Here, examples of the replenisher to be replenished to the developer include a developer stock solution, a new solution, and pure water.

  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 pipe 86 having valves 46 and 47, and are pressurized by nitrogen gas supplied through the pipe. Also, replenisher reservoirs 91 and 92 are connected to replenisher conduits 81 and 82, respectively, and replenisher is fed through valves 44 and 45 that are normally open. The replenisher lines 81 and 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 31. By operating the control valve, the replenisher stored in the replenisher reservoirs 91 and 92 is pumped and pure water is transported. Thereafter, the replenisher is joined to the circulation stirring mechanism D via the joining conduit 84, and is supplied to the developer storage tank 61 and stirred.

  When the replenisher stored in the replenisher reservoirs 91 and 92 decreases due to replenishment, the internal pressure decreases and the supply amount becomes unstable. Therefore, the valves 46 and 47 are opened as appropriate according to the decrease of the replenisher. Gas is supplied and maintained so that the internal pressure of the replenisher storage tanks 91 and 92 is maintained. When the replenisher reservoirs 91 and 92 are emptied, the valves 44 and 45 are closed and replaced with a new replenisher reservoir filled with the replenisher, or the separately procured replenisher is emptied. Refill the replenisher reservoir.

  Control of the control valves 41-43 is performed as follows, for example. If the flow rate flowing when the control valve is opened is adjusted, the amount of replenisher to be replenished can be replenished by managing the time during which the control valve is open. Based on the measured conductivity received from the measurement unit 1 and the conductivity set as the control target value, the control unit 31 opens the control valve for a predetermined time so that the replenisher of the amount to be replenished flows. A control signal is issued to the control valve.

  As the control method, various control methods used for control for adjusting the control amount to the target value can be adopted. In particular, proportional control (P control), integral control (I control), differential control (D control), and a combination of these (PI control, etc.) are preferable. More preferably, PID control is suitable.

  As described above, according to the developer management apparatus D according to the present embodiment, the developer is managed by the conductivity in the developer regardless of the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer. As a result, a component having activity in the developing action is maintained, so that it is possible to maintain a desired developing performance and to realize a developing process capable of maintaining a desired line width and remaining film thickness.

  In addition, according to the developer management apparatus D according to the present embodiment, by using the conductivity data of the conductivity value of the developer whose development performance has been confirmed in advance, the control target management value is used, thereby dissolving the developer. The photoresist concentration was 0.0 to 0.40 (wt%) (equivalent to 0.0 to 1.3 (abs)), and the absorbed carbon dioxide concentration was 0.0 to 1.3 (wt%). However, it can be used as a developer having a desired development activity. That is, according to the developer management apparatus D according to the present embodiment, the dissolved photoresist concentration of the developer is 0.25 (wt%) or more (equivalent to 0.8 (abs)) and the absorbed carbon dioxide concentration is 0.1. Even if it is 6 (wt%) or more, the developer can be used without waste, and the waste amount of developer can be reduced.

  In the above description, the example of using the conductivity data of the developer, the absorbed carbon dioxide concentration, the dissolved photorest concentration, and the conductivity data has been described. Without being limited thereto, the developer can be managed using the alkali component concentration, absorbed carbon dioxide concentration, absorbance, and alkali component concentration data of the developer.

[Second Embodiment]
FIG. 2 is a schematic diagram of a developing process for explaining the developer management apparatus D of the present embodiment. A developing solution management apparatus D of the present invention is shown together with a developing process facility A, a replenisher storing portion B, a circulation stirring mechanism C, and the like. In addition, the same code | symbol may be attached | subjected to the structure similar to the structure of 1st embodiment, and description may be abbreviate | omitted.

  The measuring unit 1 of the developer management device D includes a conductivity meter 11, a developer characteristic value correlated with the dissolved photoresist concentration of the developer, and a developer characteristic value correlated with the absorbed carbon dioxide concentration of the developer. Are provided with a plurality of measuring devices. For example, as the first characteristic value measuring means 12A for measuring the characteristic value of the developer having a correlation with the dissolved photoresist concentration, for example, an absorptiometer for measuring the absorbance at λ = 560 nm is provided. As the second characteristic value measuring means 13A for measuring the characteristic value of the developer having a correlation with the absorbed carbon dioxide concentration, a density meter for measuring the density of the developer is provided.

  Here, the characteristic value of the “correlated” developer means that the characteristic value is related to the component concentration, and the characteristic value is changed according to the change of the component concentration. For example, the developer characteristic value a having a correlation with at least the component concentration A among the component concentrations of the developer is obtained when the characteristic value a is obtained by a function having the component concentration as a variable. The concentration A is included. The characteristic value a may be a function of only the component concentration A. Usually, when the characteristic value a is a multivariable function having the component concentrations B and C as variables in addition to the component concentration A, the multivariate analysis is performed. The significance of using a method (for example, multiple regression analysis) is great.

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

  In the present embodiment, the developer sampled from the developer storage tank 61 is fed into the measurement unit 1 and the temperature is adjusted. Thereafter, the developer is sent to the conductivity meter 11, the first characteristic value measuring means 12A suction, and the second characteristic value measuring means 13A, and the conductivity, absorbance, and density are measured. Each measurement data is sent to the control means 21.

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

  Based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the calculation unit 32, the control unit 31 determines the measured dissolved photoresist concentration and measurement among the conductivity data stored in the data storage unit 23. The conductivity value of the concentration region specified by the absorbed carbon dioxide concentration is obtained. The obtained conductivity value is set as a control target value for the conductivity of the developer.

  Other configurations and operations are the same as those in the first embodiment, and are omitted.

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

  The inventor can calculate the concentration of each component of the developer with higher accuracy than the conventional method by using a multivariate analysis method (for example, multiple regression analysis method) as the calculation method, and has been difficult in the past. It was found that the absorbed carbon dioxide concentration can be measured. Using developer component concentrations (dissolved photoresist concentration and absorbed carbon dioxide concentration) calculated by multivariate analysis methods (for example, multiple regression analysis method), dissolved photoresist concentrations and absorption that have been confirmed in advance for developing properties. The target conductivity value can be easily obtained from the conductivity data having the carbon dioxide concentration and the conductivity value.

  A TMAH aqueous solution in which the alkali component concentration, dissolved photoresist concentration, and absorbed carbon dioxide concentration were variously changed was prepared as a simulated developer sample, assuming that a 2.38% TMAH aqueous solution was to be managed. The inventor conducted an experiment for determining the component concentration by a multiple regression analysis method from various characteristic values measured for these simulated developer samples. Hereinafter, a general calculation method based on the multiple regression analysis method will be described, and thereafter, a calculation method of the developer component concentration using the multiple regression analysis method will be described based on experiments conducted by the inventors.

Multiple regression analysis consists of two stages: calibration and prediction. Assume that m calibration standard solutions are prepared in an n-component multiple regression analysis. The concentration of the j-th component present in the i-th solution is represented as C _ij . Here, i = 1 to m and j = 1 to n. For each of m standard solutions, p characteristic values (for example, characteristic values such as absorbance or conductivity at a certain wavelength) A _ik (k = 1 to p) are measured. The density data and the characteristic data can be collectively represented in matrix form (C, A).

A matrix relating these matrices is called a calibration matrix, and is represented by a symbol S (S _kj ; k = 1 to p, j = 1 to n).

  It is possible to calculate S by matrix calculation from known C and A (the contents of A may include not only the same measurement value but also different measurement values. For example, conductivity, absorbance and density). Calibration stage. At this time, p> = n and m> = np must be satisfied. Since all elements of S are unknown, it is desirable that m> np. In this 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.

If p characteristic values are measured for a sample solution of unknown concentration and these are set to Au (Au _k ; k = 1 to p), the concentration Cu (Cu _j ; j = 1 to n) to be obtained by multiplying it by S ) Can be obtained.

  This is the prediction stage.

  The inventor regards the used alkaline developer (2.38% TMAH aqueous solution) as a multi-component system (n = 3) composed of three components of an alkali component, a dissolved photoresist, and absorbed carbon dioxide, and the developer. An experiment was conducted to calculate the concentration of each component by the multiple regression analysis method from three characteristic values (p = 3), that is, the conductivity value of the developer, the absorbance value at a specific wavelength, and the density value. It was. The inventor prepared 11 calibration standard solutions in which the alkali component concentration (TMAH concentration), dissolved photoresist concentration, and absorbed carbon dioxide concentration were variously changed with a 2.38% TMAH aqueous solution as the basic composition of the developer. (When m = 11, p> = n and m> np are satisfied).

  In the experiment, for 11 calibration standard solutions, the conductivity value, the absorbance value at a wavelength λ = 560 nm, and the density value were measured as the characteristic values of the developer, and the concentration of each component was determined by linear multiple 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 from here, and set the temperature controller to 25.0 ° C. again immediately before the measurement. This is the method. A conductivity meter made in-house was adopted as the conductivity meter. It measured using the conductivity flow cell made in-house which gave the platinum black process. The conductivity meter is inputted with the cell constant of the conductivity flow cell confirmed by a separate calibration operation. An in-house manufactured absorptiometer was also used. 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 employing a natural vibration method for obtaining a density from a natural frequency measured by exciting a U-shaped flow cell was used. The measured conductivity value, absorbance value, and density value are in units of mS / cm, Abs. (Absorbance), g / cm ³ .

  The calculation is based on the assumption that one of the 11 calibration standard solutions is an unknown sample, a calibration matrix is obtained with the remaining 10 standards, the concentration of the assumed unknown sample is calculated, and a known value (by other accurate analysis method) is calculated. This is based on a method (a single cross check method; Leave-One-Out method) compared with a measured concentration value or weight adjustment value.

  The results of 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 deteriorates by absorbing carbon dioxide, the concentration matrix used for the calculation includes a titration analysis method capable of accurately analyzing the concentration of alkali components and absorbed carbon dioxide. A value obtained by separately measuring the calibration standard solution was used. However, the weight preparation value was used for the dissolved photoresist concentration.

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

  Table 2 below shows the concentration matrix.

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

  Table 4 shows the calibration matrix.

  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, dissolved photoresist concentration, and absorbed carbon dioxide concentration determined by multiple regression analysis were all determined from the TMAH concentration and absorbed carbon dioxide concentration measured by titration analysis, and the adjusted weight. Both values are very close to the photoresist concentration.

  Thus, by measuring the conductivity, the absorbance at a specific wavelength, and the density of an alkaline developer, and using a multivariate analysis method (for example, multiple regression analysis), the alkali component concentration of the developer, dissolved photo It is understood that the resist concentration and the absorbed carbon dioxide concentration can be measured.

  A multivariate analysis method (for example, multiple regression analysis method) is effective for calculating and obtaining concentrations of a plurality of components. A plurality of characteristic values a, b, c,... Of the developer are measured, and component concentrations A, B, C,... Are obtained from the measured values by a multivariate analysis method (for example, multiple regression analysis method). it can. At this time, it is necessary that at least one characteristic value correlated with the component concentration is measured and used for calculation for the component concentration to be obtained.

  The component concentration is a scale indicating the relative amount of the component with respect to the whole. The component concentration of a mixed solution whose components increase or decrease over time, such as a developer that is used repeatedly, is not determined by the component alone, but is usually a function of the concentration 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 developer by a calculation method using a calibration curve.

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

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

  Further, since a multivariate analysis method (for example, multiple regression analysis method) is used in the present invention, the characteristics of the developer not having a linear relationship with a specific component concentration of the developer are used in the calculation of the component concentration of the developer. Values can also be adopted.

In addition, according to the present invention, it is not necessary to prepare a large number of samples and perform preliminary measurement to enable high-precision measurement, which is necessary in the invention of Patent Document 2. (As in the above experimental example, if the developer has n = 3 components, the number of characteristic values to be measured is 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.If the number of components is n = 2, the number of samples may be smaller.)
Furthermore, since the present invention uses a multivariate analysis method (for example, 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.

  In this embodiment, the absorbance at λ = 560 nm is exemplified as the developer characteristic value correlated with the dissolved photoresist concentration of the developer. However, the present invention is not limited to this. Absorbance at other specific wavelengths, that is, absorbance at a specific wavelength in the visible region, more preferably in the wavelength region of 360 to 600 nm, more preferably at wavelength λ = 480 nm, can also be used as the characteristic value. This is because the absorbance at specific wavelengths included in these wavelength ranges has a relatively good correspondence with the dissolved resist concentration.

  Further, although the density is exemplified as the characteristic value of the developer having a correlation with the absorbed carbon dioxide concentration of the developer, the density is not limited thereto. The characteristic value that can be adopted as the characteristic value measured in combination with the conductivity of the developing solution as the characteristic value of the developing solution having a correlation with the dissolved photoresist concentration or absorbed carbon dioxide concentration of the developing solution includes, for example, the above-mentioned specific wavelength In addition to absorbance and density, examples include ultrasonic propagation velocity, refractive index, titration end point, pH, and the like.

[Third embodiment]
FIG. 3 is a schematic diagram of a developing process for explaining the developer management apparatus D of the present embodiment. A developing solution management apparatus D of the present invention is shown together with a developing process facility A, a replenisher storing portion B, a circulation stirring mechanism C, and the like. In addition, the same code | symbol may be attached | subjected to the structure similar to the structure of 1st embodiment and 2nd embodiment, and description may be abbreviate | omitted.

  The developer management apparatus D of the present embodiment includes a measurement unit 1, a control unit 21, and a calculation unit 36. In the present embodiment, unlike the second embodiment, the control means 21 and the calculation means 36 for performing calculations are configured as separate devices.

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

  Based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the calculation means, the control unit 31 measures the measured dissolved photoresist concentration and the measured concentration among the conductivity data stored in the data storage unit 23. The conductivity value in the concentration region specified by the absorbed carbon dioxide concentration is obtained. The obtained conductivity value is set as a control target value for the conductivity of the developer.

  Other configurations and operations are the same as those in the second embodiment, and are omitted.

[Fourth embodiment]
FIG. 4 is a schematic diagram of a developing process for explaining the developer management apparatus D of the present embodiment. A developing solution management apparatus D of the present invention is shown together with a developing process facility A, a replenisher storing portion B, a circulation stirring mechanism C, and the like. In addition, the same code | symbol may be attached | subjected to the structure similar to the structure of 1st embodiment, 2nd embodiment, and 3rd embodiment, and description may be abbreviate | omitted.

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

  Based on the dissolved photoresist concentration measured by the measurement unit 1 and the absorbed carbon dioxide concentration calculated by the calculation unit 33, the control unit 31 measures the conductivity data stored in the data storage unit 23. A conductivity value in a concentration region specified by the measured dissolved photoresist concentration and the measured absorbed carbon dioxide concentration is obtained. The obtained conductivity value is set as a control target value for the conductivity of the developer.

  Other configurations and operations are the same as those in the first embodiment, and are omitted.

  The relationship between the density value of the developer and the absorbed carbon dioxide concentration value will be described. The inventor obtained the following knowledge as a result of intensive research. That is, a relatively good correspondence (linear relationship) can be obtained between the density value of the developer and the absorbed carbon dioxide concentration value regardless of the alkali component concentration or dissolved photoresist concentration of the developer. . Further, if this correspondence (linear relationship) is used, it is possible to measure the absorbed carbon dioxide concentration, which has been difficult in the past, by measuring the density of the developer with a densitometer.

The inventor used 11 calibration standard solutions used for calculating the component concentration of the developer using the multivariate analysis method as a simulated developer sample, and the alkaline component concentration (TMAH concentration), dissolved photoresist concentration, absorption Experiments were conducted to measure the carbon dioxide concentration and density, and to confirm the correlation between the component concentration and density.

Table 6 below shows the measurement results of the component concentration and density of each sample. Table 6 is a table in which the measured concentration values (wt%) in Table 5 are compared with the densities (g / cm ³ ) in Table 3.

FIG. 5 shows a graph of absorbed carbon dioxide concentration and density of each sample shown in Table 6. This graph is a graph in which the value of each sample is plotted with the absorbed carbon dioxide concentration (wt%) on the horizontal axis and the density (g / cm ³ ) on the vertical axis. A regression line was obtained from each plotted point by the least square method.

  From FIG. 5, it can be understood that the absorbed carbon dioxide concentration of the developer has a good linear relationship with the density of the developer even though the alkali component concentration and the dissolved photoresist concentration are various. From this experimental result, using the correspondence relationship (linear relationship) between the absorbed carbon dioxide concentration and density of the developer, the absorbed carbon dioxide concentration of the developer can be calculated by measuring the density of the developer. The inventor has found that this is possible.

  Therefore, regardless of the alkali component concentration (TMAH concentration) or the dissolved resist concentration, the absorbed carbon dioxide concentration of the developer can be measured by using the density meter according to this correspondence relationship (linear relationship).

  By using the relationship between the density of the developer and the absorbed carbon dioxide concentration in the computing unit 33, the absorbed carbon dioxide concentration of the developer can be easily measured.

[Fifth embodiment]
FIG. 6 is a schematic diagram of a developing process for explaining the developer management apparatus D of the present embodiment. A developing solution management apparatus D of the present invention is shown together with a developing process facility A, a replenisher storing portion B, a circulation stirring mechanism C, and the like. In addition, the same code | symbol may be attached | subjected to the structure similar to the structure of 1st embodiment and 2nd embodiment, and description may be abbreviate | omitted.

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

  Based on the dissolved photoresist concentration measured by the measurement unit 1 and the absorbed carbon dioxide concentration calculated by the computing means 37, the control unit 31 measures the conductivity data stored in the data storage unit 23. A conductivity value in a concentration region specified by the measured dissolved photoresist concentration and the measured absorbed carbon dioxide concentration is obtained. The obtained conductivity value is set as a control target value for the conductivity of the developer.

  Other configurations and operations are the same as those in the fourth embodiment, and are therefore omitted.

  As described above, according to the developer management apparatus D of the present embodiment, no matter what dissolved photoresist concentration or absorbed carbon dioxide concentration the developer has, the component having activity in the developing action in the developer is constant. Therefore, it is possible to realize a developing process capable of maintaining desired development performance and maintaining a desired line width and remaining film thickness.

  Next, a modified example of the developer management device D of the present embodiment will be described.

  1 to 4 and 6, the measurement unit 1 of the developer management device D depicts the developer management device D configured integrally with the control means 21 and the calculation means 36 and 37. The management device D is not limited to this. The measurement part 1 can also be made into a separate structure.

  In the measurement unit 1, there is an optimum installation method according to the measurement principle employed. For example, the measurement unit 1 is connected inline to the developer pipe 80 or the measurement probe is immersed in the developer storage tank 61. It may be installed as follows. The conductivity meter 11, the first concentration measuring means 12, the first characteristic value measuring means 12A, the second concentration measuring means 13, the second characteristic value measuring means 13A, and the density meter 13B are installed separately. It's okay. The developing solution management apparatus D of the present embodiment can be realized as long as each measuring unit communicates with each other so that measurement data can be exchanged with the control unit 21 and the calculation units 36 and 37.

  Depending on the measurement principle adopted by each measuring means, if reagent addition is necessary, each measuring means may be provided with a pipe for that purpose, and if a waste liquid is required, each measuring means has a pipe line for that purpose. May be provided. Even if the measuring units are not connected in series, the developer management apparatus D of this embodiment can be realized.

  In FIGS. 1 to 4 and 6, the developer management device D is such that the control valves 41 to 43 provided in the pipelines for supplying the replenisher supplied to the developer are internal components of the developer management device D. However, the developer management device D of the present embodiment is not limited to this, but is connected to the replenishing liquid pipes 81 and 82 and the pure water pipe 83. The developer management apparatus may not include the control valves 41 to 43 as internal components, and may not be connected to the conduits 81 to 83 for supplying the replenisher to the developer.

  The control means 21 in the developer management apparatus D of the present embodiment and the control valves 41 to 43 provided in the pipelines for replenishing the replenisher are the same as the control means of the developer management apparatus D. It suffices if the control signals issued by 21 are received and controlled so as to communicate with each other. Even if the control valve is not an internal component of the developer management device D, the developer management device D of this embodiment can be realized.

[Sixth embodiment]
FIG. 7 is a schematic diagram for explaining the developer management apparatus D of the present embodiment. The developer management apparatus D of this embodiment has the same configuration as that of the first embodiment. In addition, the same code | symbol may be attached | subjected to the structure similar to the structure of 1st embodiment to 5th embodiment, and description may be abbreviate | omitted.

  As shown in FIG. 7, the display means 22 of the sixth embodiment includes at least a conductivity value and an alkali component among the conductivity value, the alkali component concentration value, the dissolved photoresist concentration value, and the absorbed carbon dioxide concentration value of the developer. Any one of the concentration values can be displayed in a graph using the measurement time or the elapsed time from the start of measurement as an index.

  Further, in the present embodiment, the display unit 22 can switch the graph display of the characteristic value and the component concentration by using a switching button BT that is a display switching unit set on the screen of the display unit 22.

  The display means 22 of the sixth embodiment can also be applied in the second to fifth embodiments. The developer management apparatus according to the present invention has a predetermined density region for each concentration region specified by using the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer as an index, although various modifications as described above are allowed. Conductivity data having conductivity values of the developer that have been previously confirmed to be development performance are provided, and the concentration region specified by the measured value of the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration Using the conductivity value of the conductivity data as a control target value, a replenisher that is replenished to the developer is fed so that the conductivity of the developer becomes the control target value.

  As described above, according to the developer management method and developer management apparatus of the present invention, no matter what dissolved photoresist concentration or absorbed carbon dioxide concentration the developer is active in the developing action in the developer. Since the component having a constant is maintained, a desired development performance can be maintained, and a development process capable of maintaining a desired line width and remaining film thickness can be realized.

  As a preferred embodiment of the developing solution management apparatus, the dissolved photoresist concentration and the absorbed carbon dioxide concentration are calculated by the multivariate analysis method, so that the dissolved photoresist concentration and the absorbed carbon dioxide concentration can be obtained with high accuracy. Based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration, a target conductivity value can be obtained from the conductivity data.

  Further, as a preferred embodiment of the developer management device, the absorbed carbon dioxide concentration of the developer is calculated from the density of the developer measured by the density meter based on the correspondence relationship between the absorbed carbon dioxide concentration and the density of the developer. . Thereby, the absorbed carbon dioxide concentration of the developer can be obtained more easily. Based on the absorbed carbon dioxide concentration and the separately obtained dissolved photoresist concentration, a target conductivity value can be obtained from the conductivity data.

A ... development process equipment, B ... replenisher storage unit, C ... circulating stirring mechanism, D ... developer management device 1 ... measurement unit 11 ... conductivity meter, 12 ... first concentration measuring means, 12A ... first characteristic value measurement Means, 13 ... second concentration measuring means, 13A ... second characteristic value measuring means, 13B ... density meter 14 ... sampling pump, 15 ... sampling pipe, 16 ... outlet side pipe 21 ... control means (for example, computer), 22 ... Display means 23: data storage unit,
DESCRIPTION OF SYMBOLS 31 ... Control part, 32, 33 ... Calculation part, 36, 37 ... Calculation means 41-43 ... Control valve, 44, 45, 46, 47 ... Valve 61 ... Developer storage tank, 62 ... Overflow tank, 63 ... Liquid level 64: Development chamber hood, 65 ... Roller conveyor, 66 ... Substrate, 67 ... Developer shower nozzle 71 ... Waste pump, 72, 74 ... Circulation pump, 73, 75 ... Filter 80 ... Developer pipeline, 81, 82 ... pipeline for replenisher (developing stock solution and / or new solution), 83 ... pipeline for pure water, 84 ... confluence pipeline, 85 ... circulation pipeline, 86 ... nitrogen gas pipelines 91, 92 ... replenisher ( Development stock solution and / or new solution) storage tank

Claims (11)

The conductivity value of the developer that has been confirmed in advance to have a predetermined development performance for each concentration region that is repeatedly used and is determined by using the dissolved photoresist concentration and the absorbed carbon dioxide concentration as an index. A data storage unit in which conductivity data is stored;
Using the conductivity value stored in the data storage unit of the concentration region specified by the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer as a control target value, the conductivity of the developer A control unit that issues a control signal to a control valve provided in a conduit for supplying a replenisher to be replenished to the developer so that the control target value is
A control means comprising:
Display means for displaying at least one of the conductivity value and the alkali component concentration value among the conductivity value, alkali component concentration value, dissolved photoresist concentration value and absorbed carbon dioxide concentration value of the developer;
A developer management apparatus comprising:   The developer management apparatus according to claim 1, further comprising a display switching unit that switches a display target displayed on the display unit. The conductivity value of the developer that has been confirmed in advance to have a predetermined development performance for each concentration region that is repeatedly used and is determined by using the dissolved photoresist concentration and the absorbed carbon dioxide concentration as an index. A data storage unit in which conductivity data is stored;
Using the conductivity value stored in the data storage unit of the concentration region specified by the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer as a control target value, the conductivity of the developer A control unit that issues a control signal to a control valve provided in a conduit for supplying a replenisher to be replenished to the developer so that the control target value is
A control means comprising:
At least one of the conductivity value and the alkali component concentration value among the conductivity value, the alkali component concentration value, the dissolved photoresist concentration value, and the absorbed carbon dioxide concentration value of the developer is measured time or the elapsed time from the start of measurement. A display means for displaying a graph using as an index,
A developer management apparatus comprising:   The developer management apparatus according to claim 3, further comprising a display switching unit that switches a display target displayed on the display unit. Measuring a plurality of characteristic values of the developer, including the developer characteristic value correlated with the dissolved photoresist concentration of the developer and the developer characteristic value correlated with the absorbed carbon dioxide concentration of the developer; A plurality of measuring devices,
The control means further comprises:
An arithmetic unit for calculating a measured value of the dissolved photoresist concentration and a measured value of the absorbed carbon dioxide concentration of the developer by a multivariate analysis method from a plurality of characteristic values of the developer measured by the plurality of measuring devices,
A developing solution management apparatus according to any one of claims 1 to 4. Measuring a plurality of characteristic values of the developer, including the developer characteristic value correlated with the dissolved photoresist concentration of the developer and the developer characteristic value correlated with the absorbed carbon dioxide concentration of the developer; A plurality of measuring devices,
An operation for calculating a measured value of dissolved photoresist concentration and a measured value of absorbed carbon dioxide concentration of the developer using a multivariate analysis method from a plurality of characteristic values of the developer measured by the plurality of measuring devices. Means,
The developer management apparatus according to claim 1, further comprising: Equipped with a density meter,
The control means further comprises:
An arithmetic unit for calculating the absorbed carbon dioxide concentration value of the developer from the density value of the developer measured by the density meter based on the correspondence between the absorbed carbon dioxide concentration and density of the developer;
A developing solution management apparatus according to any one of claims 1 to 4. A density meter;
A computing means for calculating an absorbed carbon dioxide concentration value of the developer from a density value of the developer measured by the density meter based on a correspondence relationship between the absorbed carbon dioxide concentration and the density of the developer;
The developer management apparatus according to claim 1, further comprising: The developer that has been confirmed in advance to have a predetermined developing performance for each concentration region that is repeatedly used and is determined by using the absorbance and the absorbed carbon dioxide concentration correlated with the dissolved photoresist concentration of the developer exhibiting alkalinity. A data storage unit storing alkali component concentration data having the alkali component concentration value of
Using the alkali component concentration value stored in the data storage unit in the concentration region specified by the measured values of the absorbance and absorbed carbon dioxide concentration of the developer as a control target value, the alkali component concentration of the developer is the control target. A control unit that issues a control signal to a control valve provided in a conduit for feeding a replenisher to be replenished to the developer so as to be a value;
A control means comprising:
Display means for displaying at least the alkali component concentration value among the alkali component concentration value of the developer, the absorbance value correlated with the dissolved photoresist concentration, and the absorbed carbon dioxide concentration value;
A developer management apparatus comprising: The developer that has been confirmed in advance to have a predetermined developing performance for each concentration region that is repeatedly used and is determined by using the absorbance and the absorbed carbon dioxide concentration correlated with the dissolved photoresist concentration of the developer exhibiting alkalinity. A data storage unit storing alkali component concentration data having the alkali component concentration value of
Using the alkali component concentration value stored in the data storage unit in the concentration region specified by the measured values of the absorbance and absorbed carbon dioxide concentration of the developer as a control target value, the alkali component concentration of the developer is the control target. A control unit that issues a control signal to a control valve provided in a conduit for feeding a replenisher to be replenished to the developer so as to be a value;
A control means comprising:
Graph showing at least the alkali component concentration value among the alkali component concentration value of the developer, the absorbance value correlated with the dissolved photoresist concentration, and the absorbed carbon dioxide concentration value, using the measurement time or the elapsed time from the start of measurement as an index. Display means for displaying;
A developer management apparatus comprising:   The developer management apparatus according to claim 9, further comprising a display switching unit that switches a display target displayed on the display unit.

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