TWI695236B - Managing method and apparatus for developing solution - Google Patents

Abstract

The present invention provides a method and device for managing a developing solution that can maintain a desired development performance, maintain a desired line width and a residual film thickness. The developer management device D of the present invention includes a control means 21 that includes a data storage section 23 that stores conductivity data that is an alkaline developing solution for repeated use. The dissolved photoresist concentration and the absorbed carbon dioxide concentration are specified as indicators for each concentration area, which has the conductivity value of the developer that has been confirmed to reach the predetermined development performance in advance; and the control section 31 is based on the dissolution of the developer The measured value of the photoresist concentration and the measured value of the absorbed carbon dioxide concentration, and the conductivity value stored in the data storage unit 23 in the specific concentration region is set as the control target value so that the conductivity of the developer becomes the control target value. The control valves 41 to 43 that feed the flow path of the replenishing liquid supplied to the aforementioned developing liquid emit control signals.

Description

Developer management method and device

The present invention relates to a method and a device for managing a developing solution, and specifically relates to an alkali which is repeatedly used for developing a photoresist film in the development process of a semiconductor substrate and a circuit board of a liquid crystal panel (panel), etc. Method and device for managing the developing solution.

In the development process of photolithography that realizes fine wiring processing in semiconductors and liquid crystal panels, etc., an alkaline developing solution (hereinafter, referred to as the "Alkaline developer") as.

In recent years, in the process of manufacturing semiconductor and liquid crystal panel substrates, there have been significant advances in the enlargement of wafers and glass substrates, the miniaturization of wiring processes, and the integration of high density. Under such circumstances, in order to realize the miniaturization and high-density integration of wiring processing of large substrates, it is necessary to measure the concentration of the main component of the alkaline developer with higher accuracy to maintain and manage the developer.

For the measurement of the component concentration of the conventional alkaline developer, a good linear relationship can be obtained between the concentration of the alkaline component of the alkaline developer (hereinafter, referred to as "alkaline component concentration") and the conductivity Point (for example, Patent Document 1 below).

However, in recent years, the chance of the alkaline developer coming into contact with air has increased due to the development process, and because the alkaline developer absorbs carbon dioxide in the air, the amount of carbon dioxide absorbed by the alkaline developer has increased. When the concentration of absorbed carbon dioxide becomes high, the conventional developer management method suffers from problems such as processing that cannot maintain a predetermined line width.

The reason for the above-mentioned problem is that the alkaline component having development activity in the alkaline developer is consumed by the reaction of generating carbonate due to the absorption of carbon dioxide. Moreover, the alkaline component with development activity in the alkaline developing solution is also caused by the consumption of the reaction to form a photoresist salt due to the dissolution of the photoresist.

In response to the above-mentioned problems, various developer management methods have been attempted to supplement alkaline components that have been reduced due to consumption. Regarding these attempts, the concentration of the alkaline component with developing activity is maintained constant by measuring the carbonate concentration and supplementing the alkaline component consumed by the carbonate-generating reaction with the supplement solution. The same applies to the alkaline components consumed by the dissolution of the photoresist. These attempts are based on the viewpoint that the alkaline component forming the carbonate and the photoresist salt loses the development activity and becomes inactive (for example, Patent Document 2 below). [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 2561578 [Patent Document 2] Japanese Patent Laid-Open No. 2008-283162

[Problem to be solved by invention]

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

The inventors of the present case made the following findings after devoting themselves to the management of the developer. That is, by managing the conductivity value of the developer, it is possible to realize that both the carbonate and the resist salt are also partly free in the developer to help the development, and those components that were originally considered to be inactive The management of the developer aided by the development effect, and the management value of the conductivity in this way are various values depending on the concentration of absorbed carbon dioxide and the concentration of dissolved photoresist.

This is based on the fact that the alkaline components that form carbonates and photoresist salts are not deactivated, and some of them are free to help the development effect, and the free from the alkaline components with development activity and the carbonate and resist salts to help the development effect All components have an effect on the electrical conductivity. That is, the inventor of the present invention discovered that the components having a developing effect can be optimally managed by managing the conductivity value of the developing solution, and came up with the present invention.

The present invention was developed in order to solve the above-mentioned problems, and an object thereof is to provide a method and device for managing a developer capable of achieving a predetermined development performance for photoresist. [Means to solve the problem]

In order to achieve the foregoing objectives, the management method of the developer of the present invention is to measure the conductivity, dissolved photoresistance concentration and carbon dioxide absorption concentration of the alkaline developer used repeatedly; the conductivity data is based on the dissolved light of the developer Each concentration area specified by the resistance concentration and the absorbed carbon dioxide concentration as an indicator has a conductivity value of the developer that has been confirmed to reach a predetermined development performance in advance, and the dissolved light measured by the measured The resistance value and the measured absorption carbon dioxide concentration, and the conductivity value in a specific concentration area is set as the control target value of the conductivity of the developer; the supply is supplemented so that the conductivity of the developer becomes the control target value Liquid to the aforementioned developer.

According to the developer management method of the present invention, regardless of the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer, the active components in the developer that are active for development remain constant, so the desired development performance can be maintained , Can maintain the desired line width and residual film thickness of the development process.

In order to achieve the aforementioned object, the developer management device of the present invention is provided with a control means including: a data memory section that stores conductivity data, and the conductivity data is an alkaline development for repeated use Each concentration region specified by the dissolved photoresist concentration of the liquid and the absorbed carbon dioxide concentration has the conductivity value of the developer that has been confirmed to reach the predetermined development performance in advance; and the control unit uses the developer The measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration, and the conductivity value stored in the data storage unit in a specific concentration area is a control target value so that the conductivity of the developer becomes the control target value In this way, a control signal is sent to the control valve provided in the flow path for supplying the replenisher to the developer.

According to the developer management device of the present invention, regardless of the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer, the active components in the developer that are active for development remain constant, so that the desired development performance can be maintained. It is possible to realize development processing capable of maintaining a desired line width and residual film thickness.

According to a preferred aspect of the developing solution management device of the present invention, the developing solution management device is provided with a plurality of measuring devices for measuring the characteristic value of the developing solution including the correlation with the dissolved photoresist concentration of the developing solution, and The absorbed carbon dioxide concentration of the developing solution has a plurality of characteristic values of the developing solution including the characteristic values of the developing solution; the control means is further provided with an arithmetic unit, which is derived from the development measured by the plural measuring devices For a plurality of characteristic values of the liquid, a multivariate analysis method is used to calculate the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer.

According to a preferred aspect of the developer management device of the present invention, the developer management device further includes: a plurality of measuring devices that measure the characteristic value of the developer including the photoresist concentration of the developer, and A plurality of characteristic values of the developer including the characteristic value of the developer related to the concentration of carbon dioxide absorbed by the developer; and a calculation method from the plural of the developer determined by the plurality of measuring devices For each characteristic value, a multivariate analysis method is used to calculate the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer.

According to a preferred aspect of the developing solution management device of the present invention, the developing solution management device is further provided with a density meter; the aforementioned control means is further provided with an arithmetic unit, which is based on the correspondence relationship between the absorbed carbon dioxide concentration of the developing solution and the density, from The density of the developer measured by the densitometer is used to calculate the concentration of carbon dioxide absorbed by the developer.

According to a preferred aspect of the developer management device of the present invention, the developer management device is further provided with: a density meter; and an arithmetic means based on the correspondence between the concentration of the absorbed carbon dioxide of the developer and the density, from The density of the developer solution measured by a densitometer is used to calculate the concentration of carbon dioxide absorbed by the developer solution. According to the developer management method of the present invention, the alkaline concentration is measured based on the conductivity of the alkaline developer used repeatedly, the absorbance related to the dissolved photoresist concentration of the developer is measured, and the absorption of the developer is measured Carbon dioxide concentration; Alkaline concentration data is the alkaline concentration value of the developer that has been confirmed in advance to reach the predetermined development performance for each concentration region specified with the absorbance and carbon dioxide absorption of the developer as indicators , Set the alkaline concentration value in the concentration area specified by the measured absorbance and the measured absorbed carbon dioxide concentration in the alkaline concentration data as the control target value of the alkaline concentration of the developer; The replenishment solution is replenished to the developer solution so that the alkaline concentration of the developer solution becomes the control target value.

The developer management device according to the present invention is provided with a control means including: a data storage section which stores alkaline concentration data, and the aforementioned alkaline concentration data is alkaline for reuse and reuse The absorbance and the absorbed carbon dioxide concentration, which are related to the dissolved photoresist concentration of the developer, are specified as indicators for each concentration region, and have the alkaline concentration value of the aforementioned developer that has been confirmed to reach the predetermined development performance in advance; and the control section, The alkaline concentration value stored in the data storage section in a specific concentration area determined by the measured values of the absorbance of the developing solution and the absorbed carbon dioxide concentration is a control target value so that the alkaline concentration of the developing solution becomes the aforementioned The method of controlling the target value sends a control signal to the control valve provided in the flow path of the replenishing liquid supplied to the developer. [Effect of invention]

According to the present invention, regardless of the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developing solution, the active ingredients in the developing solution for the developing action remain constant, so that the desired development performance can be maintained and the desired development can be maintained. Development of line width and residual film thickness.

The preferred embodiments of the present invention will be described in detail below with appropriate reference to the drawings. However, the shape, size, size ratio, relative arrangement, etc. of the devices and the like described in the following embodiments are not limited by the contents of the drawings unless otherwise specified. It is merely a schematic illustration only as an illustrative example.

In addition, in the following description, as a specific example of the developer, a 2.38% tetramethyl ammonium hydroxide aqueous solution (hereinafter, the four The base ammonium hydroxide is called TMAH). However, the developer applicable to the present invention is not limited to this. Examples of other developer solutions to which the developer management method and management device of the present invention can be applied include aqueous solutions of inorganic compounds such as potassium hydroxide, sodium hydroxide, sodium phosphate, and sodium silicate, and trimethyl An aqueous solution of organic compounds such as trimethyl monoethanol ammonium hydroxide (choline).

In the following description, the concentration of components such as the concentration of alkaline components, the concentration of dissolved photoresistors, and the concentration of absorbed carbon dioxide are calculated from the weight percent concentration (wt%). The so-called "dissolved photoresist concentration" refers to the concentration when the dissolved photoresist is converted into the amount of photoresist; the so-called "absorbed carbon dioxide concentration" refers to the concentration when the absorbed carbon dioxide is converted into the amount of carbon dioxide.

In the development process, development is performed by dissolving the photoresist film in an unnecessary part of the photoresist film after the exposure process. The photoresist dissolved in the developer will form a photoresist salt with the alkaline component of the developer. Therefore, if the management of the developer is not properly managed, as the development process progresses, the developer will be degraded due to the consumption of alkaline components having development activity, and the development performance will be further deteriorated. At the same time, in the developing solution, the dissolved photoresist is continuously accumulated in the form of a photoresist salt formed with an alkaline component.

The photoresist system dissolved in the developing solution exhibits an interface active effect in the developing solution. Therefore, the photoresist dissolved in the developing solution improves the wettability of the developing solution to the photoresist film for development processing, and improves the affinity between the developing solution and the photoresist film. Therefore, with a developer containing a moderate amount of photoresist, the developer also enters into the fine recesses of the photoresist film, so that the photoresist film with fine irregularities can be well developed.

In addition, in the development process in recent years, with the enlargement of the substrate, a large amount of developer is repeatedly used, which increases the chance of the developer being exposed to the air. However, the alkaline developer absorbs carbon dioxide in the air once it is exposed to the air. The absorbed carbon dioxide forms carbonates with the alkaline components of the developer. Therefore, if the management of the developer is not properly managed, the alkaline components with developer activity in the developer will be consumed and reduced by the absorbed carbon dioxide. At the same time, in the developer, the absorbed carbon dioxide continues to accumulate in the form of carbonates with alkaline components.

However, the carbonate in the developer is alkaline in the developer, so it has a developing effect.

As described above, unlike the past recognition that the development activity of the development process is inactivated, the photoresist dissolved in the developer and the absorbed carbon dioxide actually contribute to the development performance of the developer. Therefore, what must be done is to manage the developer to maintain the dissolved photoresist and absorbed carbon dioxide at the optimal concentration under the condition that the dissolved photoresist and absorbed carbon dioxide are dissolved in the developer, rather than to dissolve the photoresist and absorb carbon dioxide. Completely removed developer management.

In addition, a part of the photoresist salts and carbonates generated in the developer are dissociated to generate various free ions such as photoion ions, carbonate ions, and bicarbonate ions. In addition, these free ion systems affect the conductivity of the developer with various contribution rates.

Regarding the above points, the inventors of the present case made the following findings after devoting themselves to the management of the developer. That is, by managing the conductivity value of the developer, it is possible to realize that both the carbonate and the resist salt are also partly free in the developer to help the development, and those components that were originally considered to be inactive The management of the developer aided by the development effect, and the management value of the conductivity in this way are various values depending on the concentration of absorbed carbon dioxide and the concentration of dissolved photoresist.

Therefore, the inventors of the present case envisaged a management scenario where the developer is a TMAH aqueous solution, so that the dissolved photoresist concentration and carbon dioxide absorption concentration have various changes, and the desired development performance for the photoresist and the conductivity value of the developer are obtained Relationship.

It is adjusted to change the absorbed carbon dioxide concentration from 0.0 (wt%) to 1.3 (wt%), and to make the dissolved photoresist concentration from 0.0 (wt%) to 0.40 (wt%) (equivalent to 0.0 (abs) to 1.3 ( abs)) A sample of the developer of the TMAH aqueous solution varying between. The inventors of this case conducted the following experiments: For these samples, the conductivity of the developing solution, the concentration of absorbed carbon dioxide, and the concentration of dissolved photoresist were measured to confirm the development performance, the conductivity, the concentration of absorbed carbon dioxide, and the concentration of dissolved photoresist The relationship of ingredients. A matrix (combination table) with vertical and horizontal arrangement of carbon dioxide absorption as one item and horizontal or vertical arrangement of dissolved photoresist concentration as another item was established. For each combination of the absorbed carbon dioxide concentration and the dissolved photoresist concentration, the conductivity of the developing solution that satisfies the desired development performance for the photoresist is obtained, and the columns are filled in to complete the matrix table.

Here, the so-called predetermined development performance refers to the development performance of the developer when the line width and residual film thickness to be achieved by the development process are achieved.

Exemplary measurement results of the carbon dioxide absorption concentration, dissolved photoresistance concentration, and conductivity of each sample. When the concentration of absorbed carbon dioxide is 0.0 (wt%) and the concentration of dissolved photoresist is 0.0 (wt%) (equivalent to 0.0 (abs)) (so-called new solution), the conductivity of the developer capable of exerting the desired development performance 54.58 (mS/cm).

When the concentration of absorbed carbon dioxide is 0.0 (wt%) and the concentration of dissolved photoresist is 0.25 (wt%) (equivalent to 0.8abs), the conductivity of the developer capable of exerting the predetermined development performance is 54.55 (mS/cm). When the dissolved photoresist concentration is 0.40 (wt%) (equivalent to 1.3 abs), the conductivity of the developer is 54.53 (mS/cm).

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

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

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

In addition, in the above experiment, in some concentration regions, when the absorbed carbon dioxide concentration becomes higher, the management value of the conductivity tends to become larger; when the dissolved photoresist concentration becomes higher, the management value of the conductivity becomes smaller tendency.

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

In addition, the above conductivity, carbon dioxide absorption concentration, and dissolved photoresist concentration are used to find the relationship between the conductivity, carbon dioxide absorption, dissolved photoresist concentration, and development performance, and are not based on the aforementioned values limit.

As described above, it can be understood that the conductivity that can exert the development performance has various values depending on the concentration of absorbed carbon dioxide and the concentration of dissolved photoresist. In this way, in the management of the developer, for the developer containing carbon dioxide absorption and dissolved photoresistance, the conductivity is managed at the conductivity value, and then the carbon dioxide absorption concentration and the dissolved photoresistance concentration are measured, and the conductivity is changed according to each measurement result. Value, by which the predetermined development performance can be brought into play.

That is, the conductivity data (matrix table) is memorized, and the conductivity data (matrix table) is for each concentration region specified with the dissolved photoresist concentration of the developing solution and the absorbed carbon dioxide concentration as indicators, and has been previously confirmed The conductivity value of the developer that will achieve the predetermined development performance; by using the conductivity data (matrix table), it is possible to perform the management of the developer that can bring out the predetermined development performance.

In addition, the inventors of the present case made the following findings after devoting themselves to the management of the developer. That is, by controlling the alkaline concentration value of the developer, it is possible to realize that both the carbonate and the inhibitor salt are also partly free in the developer to help the development, and those components that were originally considered to be inactive For the management of the developing solution, which is helpful for the development, the management value of the alkaline concentration in this method has various values depending on the absorbed carbon dioxide concentration and the absorbance related to the dissolved photoresist concentration.

Therefore, the inventor of the present case envisaged a management situation where the developing solution is a TMAH aqueous solution, and the absorbance of the alkaline concentration measured based on the conductivity of the alkaline developing solution and the dissolved resist concentration of the developing solution are correlated. , And the concentration of the absorbed carbon dioxide in the developer has various changes, and the relationship between the desired development performance of the photoresist and the alkaline concentration of the developer is obtained.

It is a TMAH aqueous solution that changes the concentration of absorbed carbon dioxide between 0.0 (wt%) and 1.3 (wt%) and changes the absorbance related to the concentration of dissolved photoresist between 0.0 (abs) and 1.3 (abs) Samples of the developer. The inventors of the present case conducted the following experiments: For these samples, the alkaline concentration, the carbon dioxide absorption concentration, and the absorbance of the developing solution were measured, and the development performance, the alkaline concentration, the carbon dioxide absorption concentration, and the relationship with the absorbance were confirmed. Establish a matrix table (combination table) that takes carbon dioxide absorption as one item and arranges it vertically or horizontally, and absorbance as another item. For each combination of absorbed carbon dioxide concentration and absorbance, find the alkaline concentration of the developer that meets the desired development performance for the photoresist, fill in the columns, and complete the matrix table.

Here, the so-called predetermined development performance refers to the development performance of the developer when the line width and residual film thickness to be achieved by the development process are achieved.

Examples are the measurement results of the representative carbon dioxide absorption concentration, absorbance, and alkaline concentration of each sample. When the absorption carbon dioxide concentration is 0.0 (wt%) and the absorbance is 0.0 (abs) (so-called new solution), the alkaline concentration of the developer capable of exerting the predetermined development performance is 2.380 (wt%).

When the concentration of absorbed carbon dioxide is 0.0 (wt%) and the absorbance is 0.8 abs, the alkaline concentration of the developer capable of exerting the predetermined development performance is 2.379 (wt%), and when the absorbance is 1.3 abs, the alkaline concentration of the developer It is 2.378 (wt%).

In addition, when the absorbance is 0.0 (abs) and the concentration of absorbed carbon dioxide is 0.6 (wt%), the alkaline concentration of the developer is 2.381 (wt%), and when the concentration of absorbed carbon dioxide is 1.3 (wt%), the alkali of the developer The sexual concentration is 2.388 (wt%).

In addition, when the concentration of absorbed carbon dioxide is 0.6 (wt%) and the absorbance is 0.7 abs, the alkaline concentration of the developer is 2.381 (wt%), and when the absorbance is 1.3 abs, the alkaline concentration of the developer is 2.380 (wt%) ).

In addition, when the concentration of absorbed carbon dioxide is 1.3 (wt%) and the absorbance is 0.7 abs, the alkaline concentration of the developer is 2.388 (wt%), and when the absorbance is 1.3 abs, the alkaline concentration of the developer is 2.388 (wt%) ).

In addition, in the above experiment, in certain concentration regions, it was observed that when the absorbed carbon dioxide concentration becomes higher, the management value of the alkaline concentration becomes larger; when the absorbance becomes higher, the management value of the alkaline concentration becomes smaller. .

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

The value of the absorbed carbon dioxide concentration is determined by titration analysis. The titration method is to use hydrochloric acid as the neutralizing titration reagent. As the titration device, an automatic titration device GT-200 manufactured by Mitsubishi Chemical Analytech was used. The absorbance was measured using an absorbance photometer.

In addition, the above-mentioned alkaline concentration, carbon dioxide absorption concentration, and absorbance are for finding the relationship between the alkaline concentration, carbon dioxide absorption concentration, and absorbance and development performance, and are not limited to the aforementioned numerical values.

As described above, it can be understood that the alkaline concentration capable of exerting developing performance has various values depending on the concentration of absorbed carbon dioxide and the absorbance. In this way, in the management of the developer, for the developer containing carbon dioxide absorption and dissolved photoresist, the alkaline concentration is used as the management value of the developer, and then the absorbed carbon dioxide concentration and absorbance are measured, and the alkaline concentration is changed according to each measurement result The management value of this can make the predetermined development performance play out.

That is, the alkaline concentration data (matrix table) is memorized. The alkaline concentration data (matrix table) is specific to each concentration area specified by the absorbance of the developer and the concentration of absorbed carbon dioxide. The alkaline concentration value of the developer with a predetermined development performance; by using the alkaline concentration data (matrix table), the predetermined development performance can be brought into play.

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

[First Embodiment] FIG. 1 is a schematic diagram for explaining the development process for the developer management device D of this embodiment. The developer management device D of the present invention is shown together with the development process equipment A, the replenishment liquid storage B, the circulation stirring mechanism C, and the like.

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

The developing process equipment A is mainly composed of a developer storage tank 61, an over flow tank 62, a developing chamber hood 64, a roller conveyor 65, and a developer nozzle 67 Etc. The developer storage tank 61 has a developer storage tank. The developer solution is supplemented by a replenishing solution to manage the composition. The developer storage tank 61 is provided with a liquid level gauge 63 and an overflow tank 62, and manages the increase in the amount of liquid caused by the supply of replenishment liquid. The developer storage tank 61 and the developer shower head 67 are connected through the developer line 80. The developer stored in the developer storage tank 61 is transferred to the developer shower head 67 through a filter 73 by a circulation pump 72 provided in the developer pipeline 80. The roller conveyor 65 is arranged above the developer storage tank 61 and conveys the substrate 66 on which the photoresist film is formed. The developer solution is dropped from the developer shower head 67. The substrate 66 conveyed by the roller conveyor 65 is immersed in the developer solution by passing through the dropped developer solution. Then, the developer solution is collected in the developer storage tank 61 and stored again. As mentioned above, the developer solution is used repeatedly in the development process. In addition, in the development room of a small glass substrate, processing such as avoiding absorption of carbon dioxide in the air is performed by filling with nitrogen gas or the like. In addition, the degraded developer is treated with waste liquid (drain) by actuating the waste liquid pump 71.

The circulation stirring mechanism C will be described. The circulation stirring mechanism C is mainly used to circulate and stir 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 through a circulation line 85 provided with a circulation pump 74 and a filter 75 in the middle. When the circulation pump 74 is actuated, the etching solution stored in the developer storage tank 61 is circulated through the circulation line 85. The developer system returns to the developer storage tank 61 from the side of the developer storage tank 61 via the circulation line 85. By this, the stored developer is stirred up.

In addition, in the case where the replenishing liquid flows into the circulation line 85 through the merging line 84, the inflowing replenishing liquid is supplied into the developer storage tank 61 while being mixed with the developer circulating in the circulation line 85.

Next, the developer management device D of this embodiment will be described. The developer management device D of the present embodiment is a developer management device in the following manner: The conductivity data is for each concentration region specified with the dissolved photoresist concentration and carbon dioxide absorption concentration of the alkaline developer as indicators , With the conductivity value of the developer that has been confirmed to reach the predetermined development performance in advance; use the conductivity data to specify the concentration area by the measured value of the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration The conductivity of is the control target value, and the replenishment solution is replenished to the developer in such a way that the conductivity of the developer becomes the control target value.

The developer management device D includes a measurement unit 1 and a control device 21. The developer management device D is connected to the developer storage tank 61 through the sampling pipe 15 and the 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. The conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 are connected in series to the rear stage of the sampling pump 14. The measurement unit 1 preferably includes a temperature adjustment means (not shown) for stabilizing the sampled developer to a predetermined temperature in order to improve the measurement accuracy. In this case, the temperature adjustment means is preferably installed before the measurement means. The sampling pipe 15 is connected to the sampling pump 14 of the measurement unit 1 of the developer management device D, and the outlet-side pipe 16 is connected to the pipe at the end of the measuring means.

In addition, although the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 are connected in series in FIG. 1, the conductivity meter 11, the first concentration measuring means 12. The connection method with the second concentration measuring means 13 is not limited to this. It may also be connected in parallel, or each may be independently provided with a chemical solution delivery path for measurement. The order of measurement of the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13 is not particularly asked. As long as the characteristics of each measuring means are appropriately measured in an optimal order, it is sufficient.

The control means 21 includes a data storage unit 23 and a control unit 31. In the data memory section 23, conductivity data is stored, and the conductivity data is specified for each concentration region using the dissolved photoresist concentration and carbon dioxide absorption concentration of the alkaline developing solution as indicators. The conductivity value of the developer used for the predetermined development performance.

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

The control section 31 of the control means 21 is connected to the control valves 41 to 43 provided in the flow path for supplying the replenishing solution to the developing solution via signal lines. In FIG. 1, the control valves 41 to 43 are shown 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 this embodiment. The control unit 31 controls the operation of the control valves 41 to 43 and may communicate with the control valves 41 to 43 so that the replenishing liquid can be replenished to the developer. The control valves 41 to 43 may also exist outside the developer management device D.

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

The developer liquid sampled from the developer liquid storage tank 61 is transported into the measurement unit 1 to be temperature-controlled. After the temperature is adjusted, the developer solution is sent to the conductivity meter 11, the first concentration measuring means 12, and the second concentration measuring means 13, to measure the conductivity, the dissolved photoresist concentration, and the absorbed carbon dioxide concentration. Each measurement data is transmitted to the control means 21.

The control portion 31 is set with a management value of the conductivity, and the management value of the conductivity is determined in advance for each concentration region specified with the dissolved photoresist concentration of the developing solution and the absorbed carbon dioxide concentration as indicators. The development performance of the developer corresponds to the conductivity value in the conductivity data of the conductivity value of the developer. The control unit 31 controls the measurement data received from the measurement unit 1 as follows.

The control unit 31 obtains the measured dissolved photoresist concentration and the measured value stored in the conductivity data of the data storage unit 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration received from the measuring unit 1 The conductivity value of a specific concentration region that absorbs the carbon dioxide concentration. The determined conductivity value is set as the control target value of 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 based on the comparison result. That is, when the conductivity set to the control target value is the same as the measured conductivity, the replenishing liquid is basically not added to the developer. In addition, when the conductivity set to the control target value is larger than the measured conductivity, it is sufficient to supply the replenisher that produces the effect of increasing the conductivity to the developer. In addition, when the conductivity set to the control target value is smaller than the measured conductivity, it suffices to replenish the developing solution with a replenishing solution that causes the conductivity to decrease.

Here, as the replenishing solution supplied to the developing solution, there are, for example, the original solution and the new solution of the developing solution, pure water, and the like.

The replenishment liquid is stored in the replenishment liquid storage tanks 91 and 92 of the replenishment liquid storage part C. The replenishment liquid storage tanks 91 and 92 are connected to a nitrogen gas pipeline 86 provided with valves 46 and 47, and are pressurized by nitrogen gas supplied through the pipeline. In addition, the replenishing liquid storage tanks 91 and 92 are connected to the replenishing liquid pipelines 81 and 82, respectively, and the replenishing liquid is transported through the valves 44 and 45 in the normally open state. The lines 81 and 82 for the replenishing liquid and the lines 83 for the pure water are provided with control valves 41 to 43, and the control valves 41 to 43 are controlled by the control unit 31 to be opened and closed. By the action of the control valve, the replenishing liquid stored in the replenishing liquid storage tanks 91 and 92 is pressure-fed and the pure water is conveyed. Then, the replenishing liquid system merges with the circulation stirring mechanism D through the merging line 84, and is replenished to the developer storage tank 61 for stirring.

When the replenishment liquid stored in the replenishment liquid storage tanks 91 and 92 is reduced due to replenishment, the internal pressure will decrease, resulting in unstable supply. Therefore, the valves 46 and 47 are appropriately opened and supplied in accordance with the reduction of the replenishment liquid Nitrogen gas is kept supplied so that the internal pressure of the replenishment liquid storage tanks 91 and 92 is maintained. When the replenishing fluid storage tanks 91 and 92 are empty, the valves 44 and 45 are closed and replaced with new replenishing fluid storage tanks filled with replenishing fluid, or the empty replenishing fluid storage tanks are refilled. Supplement liquid.

The control system of the control valves 41 to 43 is performed as follows, for example. As long as the flow rate circulated when the control valve is opened is adjusted, by managing the time when the control valve is opened, it is possible to replenish the amount of replenishing fluid that should be replenished. The control unit 31 sends the control valve to open the control valve in such a manner that the replenishing liquid of the amount of liquid to be replenished flows through the measured conductivity received from the measuring unit 1 and the conductivity set as the control target value Control signal for a predetermined time.

Regarding the control method, it is possible to adopt various control methods used for control in which the control amount is consistent with the target value. Specifically, proportional control (P control) (P: proportional), integral control (I control) (I: integral), differential control (D control) (D: derivative), and these control methods are preferred Combined control (PI control, etc.). More preferably, it is PID control.

According to the above, according to the developer management device D of the present embodiment, regardless of the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developer, by controlling the developer with the conductivity in the developer, the effect on development is maintained. The active component can maintain the desired development performance, and can realize the development process capable of maintaining the desired line width and residual film thickness.

In addition, according to the developer management device D of this embodiment, the control target management value is set using the conductivity data of the conductivity value of the developer whose development performance has been previously confirmed, whereby the dissolved resist concentration of the developer 0.0 (wt%) to 0.40 (wt%) (equivalent to 0.0 (abs) to 1.3 (abs)) and carbon dioxide absorption concentration of 0.0 (wt%) to 1.3 (wt%), can still be used as the desired development Use the active developer. That is, according to the developer management device D of the present embodiment, even if the dissolved photoresist concentration of the developer is 0.25 (wt%) or more (equivalent to 0.8 (abs)) and the concentration of absorbed carbon dioxide is 0.6 (wt%) or more, development The liquid can continue to be used without being treated with waste liquid, which can reduce the amount of waste liquid of the developer.

The above describes an example of using the conductivity of the developer, the concentration of absorbed carbon dioxide, and the concentration of the dissolved photoresist with the conductivity data. However, it is not limited to this. It is also possible to use the alkaline concentration of the developer, the absorbed carbon dioxide concentration, and the absorbance in combination with the alkaline concentration data to manage the developer.

[Second Embodiment] FIG. 2 is a schematic diagram for explaining the development process for the developer management device D of this embodiment. The developer management device D of the present invention is shown together with the development process equipment A, the replenishment liquid storage B, the circulation stirring mechanism C, and the like. In addition, the same configuration as that of the first embodiment is denoted by the same element symbol and its description is omitted.

The measurement unit 1 of the developer management device D includes a conductivity meter 11 and a plurality of measurement devices that measure the characteristic value of the developer related to the dissolved photoresist concentration of the developer, and the development The absorbed carbon dioxide concentration of the liquid has a characteristic value related to the developer. For example, as the first characteristic value measuring means 12A for measuring the characteristic value of the developer related to the dissolved photoresist concentration, for example, an absorbance photometer for measuring absorbance at λ=560 nm is provided. As the second characteristic value measuring means 13A for measuring the characteristic value of the developer related to the concentration of absorbed carbon dioxide, a densitometer for measuring the density of the developer is provided.

Here, the characteristic value of the "related" developer means that the characteristic value is related to the concentration of the component, and there is a relationship in which the characteristic value changes according to the change in the concentration of the component. For example, a certain characteristic value a of the developing solution related to at least the component concentration A of the component concentration of the developing solution means that when the characteristic value a is obtained as a function of the component concentration as a variable, one of the variables Contains at least component concentration A. Although the characteristic value a may be a function of only the component concentration A, usually a multivariate analysis method (for example, a multiple regression analysis method) is used when a multivariate function with component concentration B and C as variables is formed in addition to the component concentration A ) Means more.

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

In the present embodiment, the developer system sampled from the developer storage tank 61 is transported into the measurement unit 1 to perform temperature adjustment. The developer solution is transferred to the conductivity meter 11, the first characteristic value measuring means 12A, and the second characteristic value measuring means 13A after temperature adjustment to measure the electrical conductivity, absorbance, and density. Each measurement data is transmitted to the control means 21.

The calculation unit 32 calculates the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration of the developer by multivariate analysis from the absorbance and density measured by the measuring unit 1. At this time, it is also possible to calculate the measured value of the dissolved photoresist concentration and the measured value of the absorbed carbon dioxide concentration by multivariate analysis from the conductivity, absorbance, and density.

The control unit 31 obtains the measured dissolved photoresist concentration and the measured absorption stored in the conductivity data of the data storage unit 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the calculation unit 32 The carbon dioxide concentration is a specific concentration area conductivity value. The determined conductivity value is set as the control target value of the conductivity of the developer.

The rest of the configuration, operation, etc. are the same as those in the first embodiment, so they will be omitted.

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

The inventors of the present case discovered that as long as the calculation method uses a multivariate analysis method (for example, a multiple regression analysis method), it is possible to calculate the concentration of each component of the developing solution with higher accuracy than the conventional method, and it is possible to measure the historically difficult measurement. Absorb carbon dioxide concentration. As long as the component concentration (dissolved photoresist and concentration absorbed carbon dioxide concentration) of the developer solution calculated by the multivariate analysis method (for example, multiple regression analysis method) is used, the dissolved photoresist concentration, which has been previously confirmed developability, And the conductivity data of absorbed carbon dioxide concentration and conductivity value, easy to get the target conductivity value.

The inventor of the present case envisaged a management scenario of 2.38% TMAH aqueous solution, and prepared a TMAH aqueous solution with a variety of changes in the concentration of the alkaline component, the concentration of dissolved photoresistance, and the concentration of absorbed carbon dioxide as a simulated developer sample. The inventors of the present case conducted the following experiment: From various characteristic values measured for these simulated developer samples, their component concentrations were determined by complex regression analysis. Hereinafter, a general calculation method by complex regression analysis method will be described first, and then a calculation method of the component concentration of the developer using the complex regression analysis method according to an experiment conducted by the inventor of the present case will be described.

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

The matrix assigned to the association of the two matrices is called a correction matrix, and here is represented by the code S (S _kj ; k=1 to p, j=1 to n).

Matrix calculation is used to calculate S from the known C and A (the content of A is not purely homogeneous measurement value and heterogeneous measurement value is mixed. For example, conductivity and absorbance and density), this is the calibration stage. At this time, it must be p>=n and m>=np. Since each element of S is an unknown number, it is preferable that m>np. In this case, the least squares calculation is performed as follows.

Among them, T marked above represents the transposed matrix, and -1 marked above represents the inverse matrix.

As long as p characteristic values are measured for a sample solution of unknown concentration, the specific values are Au (Au _k ; k = 1 to p), and multiplied by S, the required concentration Cu (Cu _j ; j =1 to n).

The above is the prediction stage.

The inventors of this case conducted the following experiment: the used alkaline developer (2.38% TMAH aqueous solution) was regarded as a multi-component system composed of three components of alkaline component, dissolved photoresist, and carbon dioxide absorption (n=3) , Taking three characteristic values (p=3), namely the conductivity value of the developing solution, the absorbance value of a specific wavelength, and the density value as the characteristic values of the developing solution, from these characteristic values, through the above-mentioned multiple regression analysis Method to calculate the concentration of each component. The inventor of this case took 2.38% TMAH aqueous solution as the basic composition of the developer, and prepared 11 calibration standard solutions (m=11, which have various changes in alkaline component concentration (TMAH concentration), dissolved photoresistance concentration, and absorbed carbon dioxide concentration). Satisfy p>=n and m>np).

Regarding the experiment, for 11 calibration standard solutions, the conductivity value, the absorbance value at a wavelength λ = 560 nm, and the density value were determined as the characteristic values of the developer, by multiple linear regression analysis (Multiple Linear Regression-Inverse Least Squares; MLR -ILS) Calculate the concentration of each component.

Regarding the way of performing the measurement, the temperature of the calibration standard solution was adjusted to 25.0°C before proceeding. The temperature adjustment method is as follows: the bottle with the calibration standard solution is immersed in a constant temperature water tank with a temperature management near 25°C for a long time, and sampling is performed in this state, and it is adjusted again with a temperature controller (controller) immediately before the measurement To 25.0°C. The conductivity meter is a conductivity meter manufactured by our company. The measurement was performed using a conductivity flow cell (manufactured by our company) that had been subjected to platinum black treatment. The conductivity constant of the conductivity flow channel confirmed by the calibration operation is input to the conductivity meter. Absorbance photometer is also used by our company. It is an absorbance photometer equipped with a light source section with a wavelength of λ=560 nm, a photometric section, and a glass flow channel. The density measurement system uses a densitometer using the natural vibration method, that is, the density is obtained from the natural vibration frequency measured by applying vibration to the U-shaped tube flow groove. The units of the measured conductivity value, absorbance value, and density value are mS/cm, Abs. (Absorbance), and g/cm ^{3, respectively} .

Regarding the method used in the calculation (leave one cross-validation method; Leave-One-Out method), one of the 11 calibration standard solutions is selected as the unknown sample, and the calibration matrix is obtained with the remaining 10 standards to calculate the assumed The concentration of the unknown sample is compared with the known value (concentration value and weight modulation value measured by other correct analytical methods).

Table 1 below shows the results of MLR-ILS calculations.

[Table 1]

In view of the fact that the TMAH aqueous solution is strongly alkaline and easily absorbs carbon dioxide and deteriorates, when performing MLR-ILS calculations, the value of the concentration matrix used in the calculation is another titration analysis method that can accurately analyze the concentration of the alkaline component and the concentration of absorbed carbon dioxide Derived from the determination of the calibration standard solution. Among them, the weight modulation value is used for the dissolved photoresist concentration.

As for the titration method, it is the neutralization titration with hydrochloric acid as the titration reagent. As the titration device, an automatic titration device GT-200 manufactured by Mitsubishi Chemical Analytech was used.

Table 2 below shows the concentration matrix.

[Table 2]

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

[table 3]

Table 4 below shows the correction matrix.

[Table 4]

Table 5 below shows the comparison of the measured concentration values in Table 2 above and the calculated MLR-ILS values in Table 1 above.

[table 5]

As shown in Table 5 above, the TMAH concentration, dissolved photoresistance concentration, and carbon dioxide absorption concentration obtained by the multiple regression analysis method are all the same as the TMAH concentration and carbon dioxide absorption concentration determined by titration and the weight adjustment. The dissolved photoresist concentration is very similar.

As described above, it is understood that by measuring the electrical conductivity, absorbance at a specific wavelength, and density of the alkaline developer, the multicomponent analysis method (eg, multiple regression analysis) can be used to determine the concentration and dissolution of the alkaline component of the developer Photoresistance concentration and carbon dioxide absorption concentration.

The multivariate analysis method (for example, the multiple regression analysis method) is very effective in calculating the concentration of a plurality of components. By measuring a plurality of characteristic values a, b, c, ... of the developing solution, the component concentrations A, B, C, ... can be obtained from these measured values by multivariate analysis (for example, multiple regression analysis) . At this time, for the required component concentration, at least one characteristic value related to the component concentration must have at least one measured and used in the calculation.

In addition, the component concentration system is a scale indicating the relative amount of the component relative to the whole. With regard to the developer used repeatedly, the component concentration of the mixed solution whose components increase or decrease over time is usually a function of the concentration of other components and cannot be determined solely by the components. Therefore, the relationship between the characteristic value of the developer and the component concentration is often difficult to express in a flat graph. At this time, it is impossible to calculate the component concentration from the characteristic value of the developer using an algorithm using a calibration curve or the like.

If a multivariate analysis method (for example, a multiple regression analysis method) is used, as long as a set of measurement values of a plurality of characteristic values related to the concentration of the component to be calculated is collected, and these measurement values are used for calculation, the calculation A set of ingredient concentrations. The component concentration measurement by the multivariate analysis method (for example, the multiple regression analysis method) can obtain the remarkable effect that the component concentration can be measured by measuring the characteristic value even if the component concentration is difficult to be measured at the first glance in the conventional knowledge.

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

In addition, in the present invention, a multivariate analysis method (for example, a multiple regression analysis method) is used. Therefore, it is also possible to use a developer having a wireless relationship with the specific component concentration of the developer in the calculation of the component concentration of the developer Characteristic value.

In addition, according to the present invention, there is no need for the preparation and preliminary measurement of an extremely large number of samples that are necessary for the invention of the aforementioned Patent Document 2 to achieve high-precision measurement. (As in the previous experimental example, if the developer is n=3, the number of characteristic values to be measured is p=3, and the number p of samples satisfying m>=np is prepared (for example, p=11 samples) It is sufficient to perform the measurement. If the number of components n=2, the number of samples can be less.) In addition, the present invention uses a multivariate analysis method (for example, a complex regression analysis method), and therefore can accurately calculate the concentration of carbon dioxide absorbed by a developer, which is difficult to measure by conventional methods.

In the present embodiment, the characteristic value of the developer related to the dissolved photoresist concentration of the developer is exemplified by the absorbance of λ=560 nm, but it is not limited to this. In terms of characteristic values, the absorbance of other specific wavelengths can also be used, that is, the absorbance of specific wavelengths in the visible wavelength range, more preferably the absorbance of specific wavelengths in the wavelength range of 360nm to 600nm, and the absorbance of wavelength λ=480nm is more preferred . This is because there is a relatively good correspondence between the absorbance of specific wavelengths in these wavelength ranges and the concentration of the dissolution inhibitor.

In addition, the characteristic value of the developer related to the concentration of carbon dioxide absorbed by the developer is exemplified by the density, but it is not limited thereto. Regarding the characteristic value of the developing solution related to the dissolved photoresist concentration and the absorbed carbon dioxide concentration of the developing solution, the characteristic value that can be measured in accordance with the conductivity of the developing solution can be, for example, the absorbance other than the specific wavelength In addition to the density, ultrasonic propagation speed, refractive index, titration end point, pH, etc. can also be mentioned.

[Third Embodiment] FIG. 3 is a schematic diagram for explaining the development process for the developer management device D of this embodiment. The developer management device D of the present invention is shown together with the development process equipment A, the replenishment liquid storage B, the circulation stirring mechanism C, and the like. In addition, the same configuration as that of the first embodiment and the second embodiment is denoted by the same element symbol and its description is omitted.

The developer management device D of this embodiment includes a measurement unit 1, a control unit 21, and an arithmetic unit 36. Unlike the second embodiment, in the present embodiment, the control means 21 and the calculation means 36 for performing calculation are constituted by separate devices.

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

The control unit 31 obtains the measured dissolved photoresist concentration and the measured absorbed carbon dioxide stored in the conductivity data of the data storage unit 23 based on the dissolved photoresist concentration and the absorbed carbon dioxide concentration calculated by the arithmetic means Concentration and conductivity value of specific concentration area. The determined conductivity value is set as the control target value of the conductivity of the developer.

The rest of the configuration, operation, etc. are the same as those in the second embodiment, so they will be omitted.

[Fourth Embodiment] FIG. 4 is a schematic diagram for explaining the development process for the developer management device D of this embodiment. The developer management device D of the present invention is shown together with the development process equipment A, the replenishment liquid storage B, the circulation stirring mechanism C, and the like. In addition, the same configurations as those of the first embodiment, the second embodiment, and the third embodiment are denoted by the same element symbols and their descriptions are omitted.

The measuring unit 1 of this embodiment includes a conductivity meter 11, a first concentration measuring means 12, and a density meter 13B. The control means 21 includes a control unit 31, a data storage unit 23, and a calculation unit 33. The calculation unit 33 calculates the absorbed carbon dioxide concentration of the developer from the density of the developer measured by the densitometer 13B based on the correspondence between the absorbed carbon dioxide concentration and the density of the developer.

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

The rest of the configuration, operation, etc. are the same as those in the first embodiment, so they will be omitted.

The relationship between the density value of the developer and the concentration value of absorbed carbon dioxide will be described. The inventor of this case made the following findings after continuing to devote himself to research. That is, regardless of the alkaline component concentration and the dissolved photoresist concentration of the developer, a relatively good correspondence (linear relationship) can be obtained between the density value of the developer and the concentration value of absorbed carbon dioxide. In addition, as long as this correspondence relationship (linear relationship) is used, it is possible to measure the concentration of absorbed carbon dioxide that was difficult to measure in the past by measuring the density of the developer with a densitometer.

The inventors of the present case conducted the following experiment: using the 11 calibration standard solutions used in the calculation of the component concentration of the developer by the multivariate analysis method as simulated developer samples, and measuring the alkaline component concentration for these samples ( TMAH concentration), dissolved photoresist concentration, absorbed carbon dioxide concentration, and density, and confirm the relationship between component concentration and density.

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

[Table 6]

Figure 5 shows a graph of the absorbed carbon dioxide concentration and density for each sample shown in Table 6. This graph is a graph obtained by plotting the value of each sample with the carbon dioxide concentration (wt%) as the horizontal axis and the density (g/cm ³ ) as the vertical axis. From the plotted points, the regression line is calculated by the least square method.

It can be understood from Figure 5 that although there are various changes in the concentration of the alkaline component and the concentration of the dissolved photoresist in the developer, there is still a good linear relationship between the concentration of absorbed carbon dioxide and the density of the developer. The inventor of the present case discovered from this experimental result that as long as the corresponding relationship (linear relationship) between the carbon dioxide concentration and the density of the developer is used, the concentration of the developer absorbed carbon dioxide can be calculated by measuring the density of the developer .

Therefore, regardless of the alkaline component concentration (TMAH concentration) and the dissolution resistance concentration, the density of carbon dioxide absorbed by the developer can be measured using the density relationship (linear relationship) using a density meter.

The calculation unit 33 uses the relationship between the density of the developing solution and the absorbed carbon dioxide concentration to easily measure the absorbed carbon dioxide concentration of the developing solution.

[Fifth Embodiment] FIG. 6 is a schematic diagram for explaining the development process for the developer management device D of this embodiment. The developer management device D of the present invention is shown together with the development process equipment A, the replenishment liquid storage B, the circulation stirring mechanism C, and the like. In addition, the same configuration as that of the first embodiment and the second embodiment is denoted by the same element symbol and its description is omitted.

The developer management device D of this embodiment includes a measurement unit 1, a control device 21, and an arithmetic device 37. Unlike the fourth embodiment, in this embodiment, the control means 21 and the calculation means 37 for performing calculation are constituted by separate devices. The measuring unit 1 of this embodiment includes a conductivity meter 11, a first concentration measuring means 12, and a density meter 13B. The calculating means 37 calculates the absorbed carbon dioxide concentration of the developing solution from the density of the developing solution measured by the densitometer 13B based on the correspondence relationship between the absorbed carbon dioxide concentration and the density of the developing solution.

The control unit 31 obtains the measured dissolved photoresist stored in the conductivity data of the data storage unit 23 based on the dissolved photoresist concentration measured by the measuring unit 1 and the absorbed carbon dioxide concentration calculated by the calculation means 37 The concentration and the measured value of the concentration of carbon dioxide absorbed and the conductivity value of the specific concentration area. The determined conductivity value is set as the control target value of the conductivity of the developer.

The rest of the configuration, operation, etc. are the same as those in the fourth embodiment, so they will be omitted.

As described above, according to the developer management device D of the present embodiment, regardless of the dissolved photoresist concentration and carbon dioxide concentration of the developer, the components active in the developer for the development action remain constant, so the desired With the development performance, development processing capable of maintaining a desired line width and residual film thickness can be achieved.

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

Although FIG. 1 to FIG. 4 and FIG. 6 depict the developing liquid management device D in which the measuring unit 1 of the developing liquid management device D is integrated with the control means 21 and the calculation means 36 and 37, the present embodiment The developer management device D is not limited to this. It is also possible to configure the measurement unit 1 independently.

The measuring section 1 has an optimal setting method corresponding to the measuring principle adopted by each measuring means. Therefore, for example, the measuring section 1 may be connected to the developer solution line 80 in an inline manner, or may be set so that The measurement probe is immersed in the developer storage tank 61. 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 may be provided individually. The developer management device D of the present embodiment can be realized as long as each measurement means can communicate with the control means 21 and the calculation means 36, 37 in such a manner that measurement data is transmitted and received.

According to the measurement principle adopted by each measurement method, if the addition of the reagent is required, each measurement method can also be equipped with piping for adding the reagent; if there must be waste liquid, each measurement method can also be provided for waste. The pipeline used for liquid. Even if the measuring means are not connected in series, the developer management device D of this embodiment can be realized.

Although FIGS. 1 to 4 and 6 illustrate the developer management device D so that the control valves 41 to 43 provided in the flow path of the replenishment solution supplied to the developer become the developer management device D The internal components are connected to the pipelines 81 and 82 for the replenishing liquid and the pipeline 83 for the pure water, but the developer management device D of this embodiment is not limited to this. The developer management device may not have control valves 41 to 43 in the form of internal components, or it may not be connected to the pipelines 81 to 83 for replenishing the replenisher to the developer.

The control means 21 in the developer management device D of this embodiment and the control valves 41 to 43 provided in the pipeline for replenishing the replenishment liquid only need to be configured so that the control valves 41 to 43 are received by the developer management device The control signal issued by the control means 21 of D can be obtained in such a manner that the control methods communicate with each other. Even if the control valve is not constituted as an internal member of the developer management device D, the developer management device D of this embodiment can be realized.

The developing solution management device of the present invention is similar to any of the various modifications described above: it is provided with conductivity data that is specified in terms of the dissolved photoresist concentration and carbon dioxide concentration of the developing solution as indicators Each concentration area has conductivity data for the developer that has been previously confirmed to reach the predetermined development performance; it is specified by the measured value of the dissolved photoresist concentration of the developer and the measured value of the absorbed carbon dioxide concentration The conductivity value of the concentration area in the conductivity data is a control target value, and the replenishing solution supplied to the developer solution is delivered in such a manner that the conductivity of the developer solution becomes the control target value.

As described above, according to the developer management method and developer management device of the present invention, regardless of the dissolved photoresist concentration and carbon dioxide concentration of the developer, the active components in the developer that are active for development remain constant, so it is possible While maintaining the desired development performance, development processing capable of maintaining the desired line width and residual film thickness can be achieved.

A preferred aspect of the developer management device calculates the dissolved photoresist concentration and absorbed carbon dioxide concentration by a multivariate analysis method, so the dissolved photoresist concentration and absorbed carbon dioxide concentration can be determined with high accuracy. Based on these dissolved photoresist concentration and absorbed carbon dioxide concentration, the target conductivity value can be obtained from the conductivity data.

In addition, a preferred aspect of the developer management device calculates the absorbed carbon dioxide concentration of the developer from the density of the developer measured by a densitometer based on the correspondence between the absorbed carbon dioxide concentration and density of the developer. This makes it possible to more easily determine the concentration of carbon dioxide absorbed by the developer. The target conductivity value can be obtained from the conductivity data based on the absorbed carbon dioxide concentration and the dissolved photoresist concentration obtained separately.

1‧‧‧Measurement Department 11‧‧‧Conductivity meter 12‧‧‧The first concentration measurement method 12A‧‧‧The first characteristic value measuring method 13‧‧‧Second concentration measurement method 13A‧‧‧Second characteristic value measuring method 13B‧‧‧Density meter 14‧‧‧Sampling pump 15‧‧‧Sampling piping 16‧‧‧Export piping 21‧‧‧Control means (eg computer) 23‧‧‧ Data Memory Department 31‧‧‧Control Department 32、33‧‧‧Calculation Department 36、37‧‧‧Calculation method 41 to 43‧‧‧Control valve 44, 45, 46, 47 61‧‧‧Developer storage tank 62‧‧‧Overflow trough 63‧‧‧ Liquid level gauge 64‧‧‧Developing chamber cover 65‧‧‧Roller conveyor 66‧‧‧ substrate 67‧‧‧Developing liquid pouring head 71‧‧‧ Waste liquid pump 72, 74‧‧‧Circulation pump 73, 75‧‧‧ filter 80‧‧‧Developing fluid pipeline 81, 82‧‧‧ pipeline for replenishing solution (developing original solution and/or new solution) 83‧‧‧Pipeline for pure water 84‧‧‧Confluence pipeline 85‧‧‧Circulation pipeline 86‧‧‧ Nitrogen pipeline 91, 92‧‧‧ Replenisher (developing original solution and/or new solution) storage tank A‧‧‧Development process equipment B‧‧‧Replenishment liquid storage department C‧‧‧Circulation stirring mechanism D‧‧‧Development liquid management device

FIG. 1 is a schematic diagram for explaining the development process of the developer management device of the first embodiment. FIG. 2 is a schematic diagram for explaining the development process of the developer management device of the second embodiment. FIG. 3 is a schematic diagram for explaining the development process of the developer management device of the third embodiment. FIG. 4 is a schematic diagram for explaining the development process of the developer management device of the fourth embodiment. Figure 5 is a graph showing the relationship between the carbon dioxide concentration and density of the developer. FIG. 6 is a schematic diagram for explaining the development process of the developer management device of the fifth embodiment.

1‧‧‧Measurement Department

11‧‧‧Conductivity meter

12‧‧‧The first concentration measurement method

13‧‧‧Second concentration measurement method

14‧‧‧Sampling pump

15‧‧‧Sampling piping

16‧‧‧Export piping

21‧‧‧Control means (eg computer)

23‧‧‧ Data Memory Department

31‧‧‧Control Department

41 to 43‧‧‧Control valve

44, 45, 46, 47

61‧‧‧Developer storage tank

62‧‧‧Overflow trough

63‧‧‧ Liquid level gauge

64‧‧‧Developing chamber cover

65‧‧‧Roller conveyor

66‧‧‧ substrate

67‧‧‧Developing liquid pouring head

71‧‧‧ Waste liquid pump

72, 74‧‧‧Circulation pump

73, 75‧‧‧ filter

80‧‧‧Developing fluid pipeline

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

83‧‧‧Pipeline for pure water

84‧‧‧Confluence pipeline

85‧‧‧Circulation pipeline

86‧‧‧ Nitrogen pipeline

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

A‧‧‧Development process equipment

B‧‧‧Replenishment liquid storage department

C‧‧‧Circulation stirring mechanism

D‧‧‧Development liquid management device

Claims (2)

A developer management method, which is to measure the alkaline concentration based on the conductivity of the alkaline developer used repeatedly, to measure the absorbance related to the dissolved photoresist concentration of the developer, and to measure the carbon dioxide absorption concentration of the developer ; The alkaline concentration data refers to the alkaline concentration value of the developer that has been confirmed in advance to achieve the predetermined development performance for each concentration region specified using the absorbance and carbon dioxide absorption of the developer as indicators. The alkaline concentration value in the concentration area specified by the measured absorbance and the measured absorbed carbon dioxide concentration in the alkaline concentration data is set as the control target value of the alkaline concentration of the developer; The replenishing solution is replenished to the developing solution so that the alkaline concentration of the developing solution becomes the control target value. A developer management device is provided with control means, the control means is provided with: The data storage unit stores alkaline concentration data. The aforementioned alkaline concentration data is specified based on the absorbance and carbon dioxide concentration related to the dissolved photoresist concentration of the alkaline developer used repeatedly as indicators. Each concentration area of has the alkaline concentration value of the aforementioned developer that has been previously confirmed to reach the predetermined development performance; and The control section controls the alkaline concentration value stored in the data memory section in a specific concentration area specified by the absorbance of the developer and the measured value of the concentration of absorbed carbon dioxide to control the target value to make the developer alkaline When the concentration becomes the aforementioned control target value, a control signal is issued to the control valve provided in the flow path for supplying the replenishing liquid supplied to the developing solution.

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