KR101210347B1 - Method of analyzing plating solution and apparatus for performing the method - Google Patents

Abstract

Disclosed are a plating solution analysis method and an analysis device therefor. Analytical methods include the steps of taking a plating solution sample, separating the collected sample on-line by capillary electrophoresis, qualitatively and quantitatively analyzing the separated sample, and processing and controlling the analyzed data to change the plating solution composition. Steps. The analyzing apparatus includes a plating liquid sampling unit, a capillary electrophoresis apparatus for separating the sample on-line, a detecting unit for qualitative and quantitative analysis of each separated component, and a control unit for controlling the plating liquid component according to the analyzed data. do. Various components of the plating liquid can be easily analyzed and controlled.

Description

Plating solution analysis method and apparatus for performing the same {METHOD OF ANALYZING PLATING SOLUTION AND APPARATUS FOR PERFORMING THE METHOD}

The present invention relates to a plating liquid analysis method and apparatus for performing the same, and more particularly, to a method for easily analyzing a plating liquid of a semiconductor device in real time, and a plating liquid analysis apparatus for performing the same.

In semiconductor devices, aluminum is mainly used for surface treatment of metal wires, electronic circuit boards (PCBs), and various metals. Recently, copper having higher electrical conductivity than aluminum is used. In order to use copper, a technique for preventing diffusion of copper by using tantalum (Ta) and tantalum nitride (TaN), that is, a barrier fabrication technique should be applied. The development of this barrier fabrication technology makes it possible to replace metal wires with copper.

In addition to the advantage that copper has about 30% higher electrical conductivity than aluminum, copper (electro-migration), which has a decisive effect on the lifespan of semiconductor devices, can be improved up to 10 times. In order to do this, research is being conducted in various ways in almost all semiconductor industries.

Electroplating is used for the production of copper metal wires. Copper plating solution is generally used as the electrolytic solution for plating. When using pure copper sulfate solution, the single crystal size of the plated copper reaches a maximum of several μm. There is a problem that a void is formed.

In order to solve this problem, various organic compounds, that is, organic additives, are added to the plating solution to control the size of the single crystal of the plated metal and prevent pupils.

There are many types of organic additives, depending on their role in the plating process, depending on the role of the ionic electrolyte (electrolytes), accelerators, brighteners, suppressors, levelers, surfactants, Defoamers and the like.

In addition to the copper component, various plating liquid components, that is, metal components such as tin (Sn), gold (Au), and nickel (Ni) included in the solder ball may be used with organic additives such as stabilizers, surfactants, antioxidants, and complexing agents. do.

However, the organic additives tend to decrease in the concentration of the electroplating process, so the concentration must be measured and filled in short. This requires precise and accurate analysis and measurement systems. In addition, organic additive producers need to dilute or blend the raw materials of organic additives to a certain concentration, which requires a concentration measurement system.

The plating solution analysis method currently applied generally is a method called the cyclic voltammetir (CV) method or the cyclic voltammetric stripping (CVS) method, and the density | concentration is calculated | required by measuring the amount of copper which precipitates on a rotating cathode electrode. However, this method does not analyze the concentration of individual components, but only indirectly manages the concentration through the change of the overall voltage, so that accurate concentration management is difficult and reproducible. And since the compounding quantity of each component is predetermined, it is difficult to respond to the case where the consumption balance of each component is broken by the temporal change of plating conditions, etc.

On the other hand, in order to analyze the trace component in a plating liquid, the analyzer which used the ultraviolet absorbance method is used. This is to first check the absorption wavelength and dilution ratio by scanning the plating solution with an ultraviolet absorber, and to prepare a blank test solution and a calibration curve, and to calculate the content of the plating solution organic additive. However, this method has a disadvantage in that accuracy and precision are inferior and difficult to analyze in the case of very small amounts.

It is an object of the present invention to accurately monitor the concentration of organic additives, particularly accelerators and inhibitors, as well as metal ions and various ions in the plating solution with high accuracy, so as to make up for the shortage of organic additives from time to time. It is to provide a plating solution analysis method capable of maintaining a constant plating quality of.

Another object of the present invention is to provide a plating liquid analysis apparatus that can be easily and easily performed in the field of the plating liquid analysis method and can cope with changes in the composition and type of the plating liquid using a single device.

Plating solution analysis method of the present invention for achieving the above object comprises the steps of taking a sample of the plating solution, separating the collected sample by on-line capillary electrophoresis, qualitative and quantitative analysis of the separated sample and the analyzed Processing and controlling the data to change the plating liquid composition.

In one embodiment, the sample is diluted in the diluent at a ratio of about 1 to 1000 times, and the diluent is injected so that the sample amount is in the range of about 1 nL to 1 ml.

In one embodiment, the diluent is de-ionized water (DI water), sodium hydroxide (NaOH) aqueous solution, potassium hydroxide (KOH) aqueous solution, ammonium hydroxide (NH ₄ OH) aqueous solution, ethylene diamine tetraacetic acid ) Solution and a mixture thereof.

In one embodiment, the separation of the sample by the capillary electrophoresis is carried out in the voltage range of -30 ~ + 30kV.

In one embodiment, the collection of the sample is performed automatically at regular intervals, and the infusion solution comprising the sample, standard solution, buffer solution, rinse solution, diluent and deionized water used for separation is automated in a given order. It is changed to and injected.

Another object of the present invention described above is to control a plating solution component according to a plating solution sampling unit, a capillary electrophoresis apparatus for separating the sample on-line, a detection unit for qualitative and quantitative analysis of each separated component, and the analyzed data. It is achieved by a plating liquid analysis device including a control unit for performing.

In one embodiment, the device is a multi-port valve for continuously injecting a sample, a standard solution, a buffer solution, a rinse solution, a dilution solution and an injection solution containing deionized water to separate the sample taken on-line. It includes.

In one embodiment, the assay device comprises a reagent supply and treatment portion for storing and feeding treatment of an infusion solution comprising standard solution, buffer solution, rinse solution, diluent and deionized water.

In one embodiment, each injection solution is introduced to continuously inject an injection solution comprising a sample, a standard solution, a buffer solution, a rinse solution, a dilution solution and deionized water to separate the collected sample on-line. A moving stage for receiving the containing vials.

In one embodiment, the electrophoresis apparatus includes a solution supply and treatment unit for storing and supplying an injection solution including a standard solution, a buffer solution, a rinse solution, a diluent solution and deionized water.

In one embodiment, the detection unit, if necessary, at least one of a UV-Vis spectrophotometer, a titrator system, a pH electrode, a fluorescence spectrometer and a cyclic voltammetric stripping system (CVS). It includes more.

According to the plating solution analysis method according to the present invention, it is particularly applicable to semiconductor technology and the like, and it is possible to perform qualitative and quantitative analysis with high accuracy even with a very small amount of use for a plating solution containing various components and to improve process problems in a short time by enabling real time analysis. It is possible to do it, and automation is possible.

1 is a flowchart showing a plating solution analysis method according to the present invention in order.
Figure 2 is a schematic plan view showing the basic structure of the electrophoretic apparatus shown to explain the basic principle of sample separation by capillary electrophoresis.
Figure 3 is a schematic diagram for explaining the injection solution supply method and the flow of the injection solution is performed for separation of the sample by capillary electrophoresis in the plating solution analysis apparatus according to an embodiment of the present invention.
Figure 4 is a schematic diagram showing a plating liquid analysis device according to another embodiment of the present invention.
5 is a schematic view showing a plating liquid analyzing apparatus according to another embodiment of the present invention.
6 is a schematic diagram illustrating an injection solution injection vial and an outlet vial unit in a plating solution analyzer according to another exemplary embodiment of the present invention.
7 is a graph illustrating a result of analyzing a plating solution according to a plating solution analysis method according to an exemplary embodiment of the present invention.

Hereinafter, a plating liquid analysis method and an apparatus for performing the same according to an embodiment of the present invention with reference to the accompanying drawings will be described in detail. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention in order to clarify the present invention.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, or a combination thereof described in the specification, but one or more other features or numbers. It is to be understood that the present invention does not exclude in advance the possibility of the presence or the addition of steps, actions, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, a plating liquid analysis method according to embodiments of the present invention will be described in detail.

1 is a flowchart showing a plating solution analysis method according to the present invention in order.

First, an appropriate amount of sample is taken and diluted from the sample source (step S10). For example, a plating liquid applied to a semiconductor copper wiring process, a bump process, and the like contains various additives in addition to the basic metal ions and corresponding anion components. In the case of copper _{^{plating, Cu 2 +, SO 4 2}} -, and and the like, and other accelerator (accelerator), inhibitor (suppressor), a slip agent (leveler), stabilizers, surfactants, antioxidants, with an organic additive , Complexing agents and the like are used, and trace amounts of Cl ⁻ are included. Other plating liquid components include various components such as solder (Sn), gold (Au), and nickel (Ni), all of which can be analyzed according to the method of the present invention. In the plating bath, the amount required for the analysis is checked at regular intervals to check whether the plating solution applied in the field contains an appropriate amount of necessary active ingredients, no impurities, and no unwanted by-products. It is to be collected.

Samples are usually high concentrations, so that they are properly processed or diluted at the appropriate magnification for optimal analysis. Typically, the plating solution sample is diluted in the diluent at a rate of about 1 to 1000 times, and the diluent is injected so that it is in the range of about 1 nL to 1 ml in terms of the sample amount for analysis. As the diluent, various solutions including basic aqueous solution and acidic aqueous solution can be used. Specifically, DI water (de-ionized water), sodium hydroxide (NaOH) aqueous solution, potassium hydroxide (KOH) aqueous solution and ammonium hydroxide ( At least one of an aqueous NH ₄ OH) solution, an ethylene diamine tetraacetic acid (EDTA) solution, and a mixture thereof may be used.

Sampling of the plating liquid sample can be performed automatically at regular intervals. That is, the sample can be taken in real time while the plating process is being performed, and the analysis can be performed immediately. Therefore, it is possible to manage and control the data at all times by setting a desired period for a sample requiring proper composition ratio and purity.

Processes for the treatment of buffers, standards, dilutions and wastes required for analysis should also be performed. The injection solution comprising the sample, standard solution, buffer solution, rinse solution, diluent and deionized water used for separation is automatically modified to be injected in the order given.

The buffer solution is injected before and after the sample is injected into the capillary to fill the capillary, and pushes the sample to induce the injection of the sample. As the buffer solution, both cationic buffer solution and anionic buffer solution can be used. As cationic buffer solutions, it is possible to use phosphate, imidazole, tris (hydroxy) aminomethane, borate, aminopyridine, picolinic acid and mixtures thereof. The additives include cyclohexane-1,2-diaminetetraacetic acid (CDTA), sodium dodecyl sulfonate (SDS), ethylenediaminetetraacetic acid (EDTA), ethylene glycol, hydroxyisobutyric acid (HIBA), methanol, acetonitrile and mixtures thereof. The concentration should be about 2 to 12 and the range of about 1 to 500mM.

As the anionic buffer solution, chromate, PMA (1,2,4,5-benzenetetracarboxylic acid), PDC (pyridinedicarboxylic acid), BTA (1,3,5-benzenetricarboxylic acid) and mixture solutions thereof can be used. As the additive, sodium dodecyl sulfate (SDS), hexadecyltrimethylammonium bromice (CTAB), ethylene glycol, cetyltrimethylammonium hydroxide (CTAOH), diethylenetriamine (DETA), methanol, acetonitrile and mixtures thereof can be used. The pH should be in the range of about 2 to 12 and the concentration in the range of about 1 to 500mM.

As a rinse solution for washing samples, buffers, and the like deposited on vials and capillaries, deionized water, basic aqueous solutions, acidic aqueous solutions and the like can be used. As the basic aqueous solution, an aqueous sodium hydroxide solution, a potassium hydroxide aqueous solution, or the like having a concentration of 1 M or less can be used, and an aqueous hydrochloric acid solution or a nitric acid aqueous solution having a concentration of 1 M or less can be used.

The analytical sample and other injection solution are supplied to the vial through a means such as a pressure difference, height difference, voltage application, and the like to perform a separation process by capillary electrophoresis (step S20). Separation of the sample by the capillary electrophoresis is performed by applying a voltage in the range of -30 ~ + 30kV.

When the injected sample is separated sequentially while passing through the capillary, each component is analyzed and monitored in an appropriate manner (step S30). As the analytical method, any conventionally known method is applicable. Detection is possible using diodes, UV, laser-induced fluorescence (LIF), and each component in the sample can be analyzed qualitatively and quantitatively.

In addition to the analytical method of the present invention, it is possible to add a cyclic voltammetric stripping system (CVS) as an auxiliary analyzer to confirm the plating progress during plating liquid analysis, and to measure a transition metal, an additive, etc., using a UV-Vis spectrophotometer. The measuring method used, a titration method for measuring chlorine ions, metals, acids and the like, a pH electrode for measuring pH, and the like may be further used. As needed, the light source of a suitable wavelength is provided.

Thereafter, the obtained data / information is processed and controlled (step S40). The results of analysis on the sample taken should be compared with the data on the standard sample to assess whether the sample contains the required amount in the appropriate amount.

Based on the results of the comparison, data / information on the analyzed sample is obtained and controlled. On the basis of the obtained data, it is necessary to replenish the specific components that are lacking or to remove unnecessary components to prepare the optimum plating solution and apply it to the plating process. Eventually, based on the data collected and analyzed in real time, the plating liquid components are adjusted and controlled to be changed to the optimized plating liquid.

According to such a plating liquid analysis method, it is possible to separate and quantify ions composed of various components by using a difference in mobility depending on the charge of ions and the like under voltage conditions applied in an aqueous solution. Even if the amount of each component is a few nℓ level, it can be easily analyzed in a short time, and real time analysis and control is possible. In addition, since on-line analysis is possible at regular intervals, information on the environment of the plating liquid can be sensitively obtained and immediately responded to, thereby contributing to process problem improvement and yield improvement.

Hereinafter, the capillary electrophoresis method applied in the present invention will be described.

Figure 2 is a schematic plan view showing the basic structure of the electrophoretic apparatus shown to explain the basic principle of sample separation by capillary electrophoresis.

Referring to FIG. 2, an injection vial 22a, an exit vial 22b, and a capillary tube 21 are provided therebetween to receive a solution. The capillary tube 21 is provided with a detection unit 25. The first electrode 23a and the second electrode 23b made of platinum are respectively placed in the injection vial 22a containing the sample solution and the discharge vial 22b containing the buffer solution, and the electric field is applied using the voltage applying device 26. When you pass, each ion moves to the oppositely charged electrode.

Capillary electrophoresis is an electrophoresis method using capillary tubes instead of paper, polymers or gels to increase separation efficiency and speed compared to conventional methods. Many molecules are either positively or negatively charged in aqueous solutions, and when an external electric field is applied, each ion moves to the oppositely charged electrode. Electrophoretic techniques in small-diameter capillaries require high electric fields. This is because capillary tubes effectively consume the generated heat. Increasing the field strength increases the separation efficiency and shortens the separation time.

Electrophoresis in capillaries, like general electrophoresis, produces electrophoretic flow and electroosmotic flow. Electrophoretic flow is a phenomenon in which charged solutes move to electrodes of opposite charge, and electroosmotic flow is a force that causes fluid to always move in a constant direction in capillary electrophoresis. In the case of molten silica capillaries, the walls are negatively charged in aqueous solution due to ionization of the surface silanol groups. Thus, at the interface between the silica surface and the solution, unlike most solutions, positively charged electrolytes gather to form a double layer that does not move. This positively charged property continues to the movable diffusion layer. When the electric field is applied parallel to the silica surface, more ions near the surface move to the cathode, where the ions are solvated to attract and move the solvent.

Since electroosmotic flow is larger than electrophoretic flow, all components move in the same direction regardless of charge. In the case of cations, electrophoretic flow and electroosmotic flow are in the same direction, so they are separated first, followed by neutral substances subject to electroosmotic flow, and finally, anions having opposite directions of electrophoretic movement and electroosmotic movement are separated. do. Even in the case of cations, small ions are separated first, and large ions are separated later, and in the case of neutral substances or anions, the respective components are separated in the same manner.

Figure 3 is a schematic perspective view for explaining the injection solution supply method and the flow of the injection solution is performed for the separation of the sample by capillary electrophoresis in the plating solution analysis apparatus according to an embodiment of the present invention.

Referring to FIG. 3, an injection vial 31, an outlet vial 32, and a multi-port valve 33 are shown. The injection vial 31 is provided with the injection vial injection port 31a and the injection vial discharge port 31b, and the discharge vial 32 is provided with the discharge vial injection port 32a and the discharge vial discharge port 32b. Each inlet 31a, 32a is located at the bottom of each vial 31, 32 and each outlet 31b, 32b is disposed at the top of each vial 31, 32 so that the solution is at the bottom of the vial 31, 32. It is injected into and discharged to the top. Capillaries 34 are connected between the two vials 31 and 32 and are provided with electrodes (not shown) on the upper surfaces of the vials 31 and 32.

The location of the inlet and outlet in the vial for supplying the respective injection solutions is not particularly limited as shown in FIG. 3 and may be any structure as long as the flow of the solutions is possible. That is, it is also possible to form the inlet so that there is no difference in height of the outlet, it is also possible that the inlet is disposed above the outlet.

Vials 31 and 32 are commonly used for the various solutions supplied. The injection vial 31 is injected with a sample for detection, a buffer solution, a rinse solution, a standard solution, etc. as necessary, which can be easily changed through the multi-port valve 33. In order to perform the analysis in capillary electrophoresis, for example, rinse 1 → rinse 2 → buffer solution → sample injection → buffer solution → high voltage application → rinse 1 → rinse 2, and the like. As a result, more than five or six chemicals are used to complete the analytical process, which simplifies the supply process, thus improving the overall analytical process.

According to the apparatus according to the present embodiment, in order to inject a variety of solutions, it is not necessary to repeatedly replace the vials containing each solution or inject the solutions in order into one vial, rinse and discharge as needed. . It is possible to continuously inject or modify the solution by changing the injected solution using a multi-port valve and flowing the solution through the inlet and outlet. That is, by using the multi-port valve 33 connected to the inlet 31a of the injection vial 31, it is possible to provide the necessary solutions in order and on-line. For example, the sample supplied through the sample inlet 33a supplied from the sample container (not shown) moves to the center of the multi-port valve 33, which is supplied to the injection vial 31 through the injection vial inlet 31a. do. After the injection of the sample, the buffer solution is supplied from the buffer solution container (not shown) through the injection port 31a of the injection vial 31 through the buffer solution injection port 33b of the multi-port valve 33. In the same manner, the first rinse solution is supplied through the first rinse solution inlet 33c, the second rinse solution is supplied through the second rinse solution inlet 33d, and the standard solution is supplied through the standard solution inlet 33e. Do it.

The discharge vial 32 also operates in the same manner as the injection vial 31 and the necessary solution flows through the injection port 32a and the discharge port 32b of the discharge vial 32. However, in the case of the discharge vial 32, a solution such as a rinse liquid, a buffer solution, or the like is injected through the discharge vial inlet 32a and discharged through the discharge vial outlet 32b, and is injected through the capillary tube 34. The sample solution discharged from the vial 31 is also discharged through the discharge vial discharge port 32b.

Figure 4 is a schematic diagram showing a plating liquid analysis device according to another embodiment of the present invention. FIG. 4 corresponds to an apparatus configured by applying the vial and the multi-port valve shown in FIG. 3.

Referring to Figure 4, the plating liquid analysis method according to another embodiment of the present invention will be described with reference to the device. The plating liquid analyzing apparatus according to the present embodiment largely includes a sample introduction & dilution unit (SI & DU) and a capillary electrophoresis unit (CEU). Others include deionized water supply unit, plating solution supply unit, solution supply and treatment unit, solution discharge unit, and control unit.

For example, the plating liquid is taken from the plating bath 41 in the line where the semiconductor plating process is performed to be collected in the sample container 42. The plating liquid is taken only as necessary and the excess amount is recovered to the plating tank 41 again. As a result, the plating liquid is circulated or discharged by the circulation system. The sample taken in the sample container 42 is taken to the required amount by using the syringe (S) and moved to the dilution tank 43, and the diluent such as deionized water is added to dilute the sample to a concentration suitable for analysis. Before analyzing the sample, the standard solution 44 is injected into the dilution tank 43 and comparative data is obtained first. L is a liquid flow controller (LFC). The LFC can be replaced by other metering pumps such as syringe pumps, diaphragm pumps, peristaltic pumps and the like. The prepared sample is introduced into a capillary electrophoresis unit (CEU) to perform the analysis.

In the present embodiment, various solutions are introduced into the capillary electrophoresis unit (CEU) using the multi-port valve 54. The buffer solution 45a, the first rinse solution 45b, the second rinse solution 45c, Deionized water 45d and the like can be easily supplied using the multi-port valve 54. In the present embodiment, a hexagonal multi-port valve 54 having six ports is illustrated. The eight-port hexagonal multi-port valve is provided to allow continuous injection of eight solutions. Any form that can be supplied is possible. As a result, it is possible to supply all the chemical solutions required for analysis on-line, so that the processing can be performed from the introduction of the sample to the detection in a short time, and the level is almost real time.

Various solutions, including the sample, are supplied to the injection vial 46a using a pump. Syringe pumps, peristaltic pumps (peristaltic pumps), diaphragm pumps (diaphram pumps), etc. may be used as the pump. In addition, the sample may be supplied by applying pressure or using a height difference.

The injection vial 46a is connected through the discharge vial 46b and the capillary 47. The capillary tube 47 is provided with a detection unit 48 for detection of components that are separated in sequence and a control unit C for processing and controlling the plating liquid components according to the data / information obtained, and the injection vial 46a and the discharge vial 46b. ) Is connected to a voltage applying device 49 for applying an electric field separately from the capillary 47. Where various solutions are injected, syringes (S), liquid flow regulators (LFC), valves (v / v), pumps (P), discharge pumps (Pd), etc. are provided as necessary. Di means deionized water to be injected, Do means deionized water to be discharged and W means waste.

By using the above-described plating liquid analysis device, it is possible to analyze with high accuracy while using a small amount of sample. Preferably, the sample is diluted in the diluent at a rate of about 1 to 1000 times, and the diluent is injected so that the sample amount is in the range of about 1 nL to 1 ml. In addition, it is possible to perform almost real-time analysis as compared to the conventionally required about 2 hours or more to analyze the plating liquid components. The configuration of the equipment is simple and there is no need to set new conditions even if the plating liquid composition changes. And if an unknown signal is confirmed, this means that there is a by-product (by-product), so it is easy to check this and it is possible to check the influence by the by-product.

It also quantifies the analytical data for the standard solution, displays and / or outputs the result in comparison with the sample value, and adds or subtracts specific components based on the comparison value to achieve the desired plating solution characteristics. It is possible to manage the composition.

5 is a schematic view showing a plating liquid analyzing apparatus according to another embodiment of the present invention.

Referring to Figure 5, it will be described with the plating liquid analysis method according to another embodiment of the present invention. The plating liquid analyzing apparatus according to the present embodiment largely includes a sample introduction & dilution unit (SI & DU) and a capillary electrophoresis unit (CEU). In addition, a deionized water supply part, a plating liquid supply part, a solution supply and treatment part, a solution discharge part, a control part C, etc. are included.

For example, the plating liquid is taken from the plating bath 51 in the line where the semiconductor plating process is performed to be collected in the sample container 52. The plating liquid is taken only as necessary and the excess amount is recovered to the plating tank 51 again. The sample taken in the sample container 52 is transferred to the dilution tank 53 using the syringe S, and a diluent such as deionized water is added to dilute the sample to a concentration suitable for analysis. If necessary, the standard solution 54 is injected into the dilution tank 53. L is a liquid flow regulator (LFC). The prepared sample is introduced into a capillary electrophoresis unit (CEU) to perform the analysis.

According to the present embodiment, a solution supply for storing and supplying an injection solution such as a first rinse solution 55a, a second rinse solution 55b, deionized water 55c, and a buffer solution 55d, which are chemical solutions required for analysis, is provided. And a processing unit is provided. Sample and standard solution vials (56a), first rinse solution vials (56b), second rinse solution vials (56c), deionized water vials (56d), buffered solution vials (56e), and the like, which are supplied with the required solution therefrom. Xz-direction moving stage 60 for mounting vials such as the discharge vial 56f, the first discharge vial 56g, the second discharge vial 56h, the third discharge vial 56i, and the buffer solution discharge vial 56j. Is also provided.

The capillary tube 57 is provided with a detection unit 58 for the detection of components and a control unit C for processing and controlling the obtained data / information, and a voltage applying device 59 for applying an electric field together with the capillary tube 57. It is provided.

According to this embodiment, each vial is mounted on the x-z direction moving stage 60, and individual vials can be detached and mounted as necessary. Since the capillary tube 57 maintains a fixed gap, two vials are arranged to form a set. That is, the sample and standard solution vial 56a and the first discharge vial 56f, the first rinse solution vial 56b and the second discharge vial 56g, the second rinse solution vial 56c and the third discharge vial ( 56h), deionized water vial 56d and deionized water discharge vial 56i, and buffered solution vial 56e and buffered solution discharged vial 56j. In order to change the type of solution, the moving stage 60 is moved in the x direction and the z direction to detach and mount the vial, or to connect or disconnect the vial necessary for the capillary tube 57 having a fixed length.

As a result, it is possible to supply all the chemical solutions required for analysis on-line, so that the processing can be performed from the introduction of the sample to the detection in a short time, and the level is almost real time.

A variety of solutions, including the sample, are supplied to each injection vial using a pump. Where various solutions are injected, syringes (S), liquid flow regulators (LFC), valves (v / v), pumps (P), discharge pumps (Pd), etc. are provided as necessary. Di means deionized water injection, Do means deionized water discharge and W means waste.

By using the above-described plating liquid analysis device, it is possible to analyze with high accuracy while using a small amount of sample. Preferably, the sample is diluted in the diluent at a rate of about 1 to 1000 times and used in the range of about 1 nL to 1 ml sample injection amount. In addition, it is possible to perform almost real-time analysis as compared to the conventionally required about 2 hours or more to analyze the plating liquid components. The configuration of the equipment is simple and there is no need to set new conditions even if the plating liquid composition changes. And if an unknown signal is confirmed, this means that there is a by-product (by-product), so it is easy to check this and it is possible to check the influence by the by-product.

6 is a schematic diagram illustrating an injection solution injection vial and an outlet vial unit in a plating solution analyzer according to another exemplary embodiment of the present invention.

According to another embodiment shown in FIG. 6, the same configuration as that of the plating liquid analyzer shown in FIG. 5 is applied, but the type of the solution injected into the vial 62 is changed. That is, sample vials 62a, buffer solution vials 62b, first rinse solution vials 62c, second rinse solution vials 62d, third rinse solution vials 62e, standard solution vials 62f, spares Injection vials such as vials 62g, first discharge vial 62h, buffer solution discharge vial 62i, second discharge vial 62j, third discharge vial 62k, fourth discharge vial 62L ), Fifth discharge vials 62m, extra discharge vials 62n, and the like, are arranged on the xz direction moving stage 63. Each vial is provided with a sample inlet and a sample outlet as shown in the sample vial 62a.

For analysis of the sample, the capillary tube 61a is connected to the sample vial 62a and the first discharge vial 61h. When the sample is injected into the capillary to some extent, the capillary is moved as 61b to connect the buffer solution vial 62b and the buffer solution discharge vial 62i to inject the buffer solution. The movement is performed using the x-z direction movement stage 63. After the analysis is complete, the sample and the buffer are drained and the capillary is cleaned. To this end, the x-z direction moving stage 63 is driven to inject the rinse solution so as to connect the capillary with the first rinse solution vial 62c and the second discharge vial 62j. The capillary is then moved in the same manner to rinse with the second rinse solution, rinse with the third rinse solution, and with the third rinse solution. As shown in this embodiment, an extra vial 62g and an extra discharge vial 62n may be provided as necessary.

Thus, if the type and order of injection required for the capillary electrophoresis is determined, it is possible to easily change and apply as necessary. Accordingly, the plating liquid can be easily analyzed and controlled by capillary electrophoresis.

7 is a graph illustrating a result of analyzing a plating solution according to a plating solution analysis method according to an exemplary embodiment of the present invention. The result analysis graph by capillary electrophoresis is called electropherogram.

For the experiment, a sample of the plating solution applied to the copper wiring process was taken and diluted about 20-fold with deionized water. This was analyzed using the device as shown in FIG. 4. Before injecting the sample, the capillary was cleaned for 1 minute using 0.1 M aqueous NaOH solution as the first rinse solution and then the capillary for 1 minute using deionized water. The capillary was then filled using 10 mM of pyridinedicarboxylic acid (PDC) as a buffer solution. Samples were injected for 5 seconds. Sample injection was carried out under pressure conditions of 0.5 psi. Voltage was applied at −30 kV for 10 minutes and capillary analysis was performed. The measurement wavelength was 230 nm. After the analysis was completed, the capillary was washed again with the first rinse solution for 1 minute and with deionized water for 1 minute.

Referring to Figure 7, it can be seen that various components are analyzed over time. Anions are analyzed first, followed by neutral ions and cations, and the analysis is almost complete with high precision within about 400 seconds. In particular, it can be seen that analysis of organic additives such as inhibitors and accelerators is possible.

In the above, an analysis apparatus according to various embodiments is exemplified. In addition, various examples will be possible without departing from the spirit of the present invention. For example, two or more capillary electrophoresis apparatuses can be used in parallel connection if necessary. It is also possible to add a secondary analyzer to verify plating progress.

According to the analytical method of the present invention as described above, it is possible to qualitatively and quantitatively analyze various components such as metal ions, various anions, and organic additives included in a plating solution applied to a semiconductor process in recent years. In addition, the analytical device of the present invention is capable of separating and quantifying ions using a difference in mobility according to the charge of ions, etc. under a voltage condition applied in an aqueous solution. It is possible to analyze with accuracy. Identifying unknown signals can easily identify side products that interfere with the process.

In addition, by automating the solution injection method can improve the convenience of the operator and improve the process yield, it is possible to easily change and control the plating liquid composition and type as necessary.

As described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art without departing from the spirit and scope of the present invention described in the following specific claims It will be appreciated that various modifications and variations can be made in the present invention.

21, 47, 57, 61a, 61b: capillary 22a, 31, 46a: injection vial
22b, 32, 46b: discharge vial 23a: first electrode
23b: second electrode 24a: sample solution
24b: buffer solution 25: detector
26, 49, 59: voltage applying device 33, 45: multi-port valve
41, 51: plating bath 42, 52: sample container
43, 53: dilution tank 44, 54: standard solution
48, 58: detection unit 60, 63: xz direction moving stage

Claims (14)

Collecting a plating liquid sample;
Separating the collected sample on-line by capillary electrophoresis;
Qualitative and quantitative analysis of the separated sample; And
Processing and controlling the analyzed data to change the plating liquid composition,
Sampling of the sample is performed automatically at regular intervals, and the injection solution containing the sample, the standard solution, the buffer solution, the rinse solution, the dilution solution and the deionized water used for separation is automatically changed and injected in the given order. Characteristic analysis method. The analysis method according to claim 1, wherein the sample is diluted in a dilution liquid at a ratio of 1 to 1000 times, and the diluent is injected so that the sample amount is in the range of 1 nL to 1 ml. According to claim 2, The diluent is DI water (de-ionized water), sodium hydroxide (NaOH) aqueous solution, potassium hydroxide (KOH) aqueous solution, ammonium hydroxide (NH ₄ OH) aqueous solution, ethylene diamine tetraacetic acid ) At least one of a solution and a mixture thereof. The analysis method according to claim 1, wherein the separation of the sample by the capillary electrophoresis is performed at a voltage range of -30 to +30 kV. delete Plating liquid sampling unit;
Capillary electrophoresis apparatus for separating the sample on-line;
A detector for qualitatively and quantitatively analyzing each separated component;
A control unit for controlling the plating liquid component according to the analyzed data; And
And a multi-port valve for continuously injecting an injection solution including a sample, a standard solution, a buffer solution, a rinse solution, a dilution solution, and deionized water to separate the collected sample on-line. delete The analysis apparatus of claim 6, wherein the analysis apparatus comprises a reagent supply and a treatment unit for storing and supplying an injection solution including a standard solution, a buffer solution, a rinse solution, a diluent solution, and deionized water. The analysis device of claim 6, wherein the analysis device comprises vials for receiving the respective injection solutions for analysis of a sample, and the vial includes an inlet and an outlet. The analysis device of claim 9, wherein a capillary tube and an electrode are accommodated on an upper surface of the vial. The injection solution of claim 6, wherein each injection solution is continuously injected to continuously inject an injection solution including a sample, a standard solution, a buffer solution, a rinse solution, a dilution solution and deionized water to separate the collected sample on-line. Plating liquid analysis apparatus comprising a moving stage for receiving the containing vial. 12. The analysis device of claim 11, wherein the electrophoresis device comprises a solution supply and treatment unit for storing and supplying an injection solution containing a standard solution, a buffer solution, a rinse solution, a dilution solution and deionized water. The analysis apparatus of claim 11, wherein a capillary tube and an electrode are accommodated on an upper surface of the vial. The method of claim 6, wherein the detection unit further comprises at least one of a UV-Vis spectrophotometer, a titrator system, a pH electrode, a fluorescence spectrometer, and a cyclic voltammetric stripping system (CVS). Analysis device, characterized in that.

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