An on-line copper and iron ion analysis system and method for PCB via filling process chemical solution

Abstract

The present invention belongs to the technical field of wet process chemical analysis and sampling, and particularly relates to an online copper and iron ion analysis system and method for PCB via filling process chemicals. An online copper and iron ion analysis system for PCB via filling process chemicals includes the following modules: a sampling module, a copper ion detection module, an iron ion detection module, and a liquid discharge module; after being detected by the copper ion detection module, the liquid medicine is sent to the iron ion detection module. The present invention can achieve one-time sampling and simultaneously detect copper ions or iron ions, realizing online monitoring of the bath liquid in multiple slots, without the need for multiple manual samplings; it can avoid possible harm to the human body caused by the surrounding terrain and environment during sampling; it can also save human resources, solve the problem of difficult employment in the general trend, shorten the sampling and analysis time, reduce the monitoring cost, and eliminate the influence of human factors in the data processing process, improving the detection efficiency and accuracy, and having wide popularization and application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of wet process chemical analysis and sampling, and particularly relates to an on-line copper and iron ion analysis system and method for PCB via filling process chemicals. Background Art

[0002] PCB, also known as printed circuit board, is a support for electronic components and a carrier for electrical connection of electronic components, and is an important electronic component. The via filling process in its manufacturing process is a process of realizing the circuit board path by impregnating chemicals, and the quality control of the chemicals directly affects the final yield. Therefore, it is necessary to detect the copper and iron ion concentrations in the chemicals of the copper plating via filling step in real time. At present, the main means of monitoring process chemicals in China is to manually sample and then analyze the copper and iron ion content in the chemicals. The influence of human factors on the test results is relatively large, and the detection of a single bath solution takes a long time. When there are many process production lines, the detection frequency of the bath solution concentration can only be reduced, which is not conducive to quality control. Moreover, manual sampling is used for analysis by titration or instrumental methods. There are problems in the detection process of this method, such as many steps, long time consumption, and great danger to the human body in the surrounding environment of the sampling point. In particular: 1) The bath solutions are all chemical reagents with strong corrosiveness, and the acid gas is harmful to the human respiratory tract and skin, causing great harm in the long run; 2) The terrain around the chemical solution tank is complex, and industrial accidents are likely to occur; 3) Under the general environmental conditions, the number of technical practitioners for on-site analysis has decreased; 4) Manual sampling and analysis of multiple bath positions take a long time and are costly; 5) There are many steps in the sample analysis process, and the influence of human factors is large, increasing the error tolerance rate; 6) To detect copper ions or iron ions, it is necessary to sample twice or take one sample and divide it into two parts for detection, and it is impossible to detect the contents of two ions in a liquid sampled once; 7) It is impossible to monitor the bath solutions in multiple bath positions simultaneously. Summary of the Invention

[0003] The on-line copper and iron ion analysis system and method for PCB via filling process chemicals of the present invention can complete the detection of copper and iron ions through one sampling, and can arrange multiple parallel sampling modules and standard solution modules, which can not only synchronously detect multiple bath solutions, but also calibrate the detection module in real time according to needs during monitoring, solving the defects of the prior art that central sampling is harmful to the human body, the labor time for multi-bath position sampling is high, the detection efficiency is low and the detection results are inaccurate.

[0004] To solve the above technical problems, one of the purposes is to propose an on-line copper and iron ion analysis system and method for PCB via filling process chemicals, and its specific technical solutions are as follows:

[0005] An on-line copper and iron ion analysis system for PCB via filling process chemicals includes the following modules:

[0006] A sampling module for extracting the chemical solution to be detected from the bath solution;

[0007] A copper ion detection module that receives the liquid medicine to be detected extracted by the sampling module and detects the copper ion concentration in the liquid medicine;

[0008] An iron ion detection module that receives the liquid medicine after being detected by the copper ion detection module and detects the iron ion concentration in the liquid medicine:

[0009] A liquid discharge module for collecting and discharging the waste liquid medicine after detection.

[0010] The sampling module includes a filtering module and an antifoaming module, where

[0011] The filtering module is used to extract the liquid medicine to be detected from the bath liquid and filter out the liquid oily impurities, suspended substances or flocculates, and solid particle impurities therein;

[0012] The antifoaming module is used to sample the filtered liquid medicine to be detected and eliminate the bubbles therein to reduce detection interference.

[0013] It further includes a reflux module. The reflux module first sends the filtered and defoamed liquid medicine to be detected back to the bath liquid, and after a certain period of time, it sends the liquid medicine to be detected into the copper ion detection module.

[0014] The sampling module is multi-channel. The multi-channel sampling modules are arranged in parallel, and each sampling module extracts the liquid medicine to be detected from different bath liquids;

[0015] The on-line copper and iron ion analysis system for PCB via filling process medicine further includes:

[0016] A first switching module that is connected to the multi-channel sampling modules simultaneously and switches to convey the liquid medicine to be detected extracted by different sampling modules to the copper ion detection module.

[0017] It further includes: a standard solution module containing a liquid medicine with a determined standard value;

[0018] A second switching module. The standard solution module and the first switching module are connected in parallel to the second switching module;

[0019] The liquid medicine in the standard solution module is sent into the copper ion detection module through the second switching module.

[0020] It further includes: a third switching module and an iron ion dilution module. The iron ion dilution module and the outlet side of the copper ion detection module are connected in parallel to the third switching module, and the third switching module quantitatively dilutes the liquid medicine and then sends it into the iron ion detection module for detection.

[0021] A quantitative liquid addition module is provided inside the iron ion detection module. The liquid medicine after the copper ion detection module finishes detection is divided into two parts. One part is sampled by the quantitative liquid addition module and then diluted to the measurement range of the iron ion detection module by the iron ion dilution module; the other part is sent to the liquid discharge module.

[0022] An on-line copper and iron ion analysis method for PCB via filling process medicine includes the following steps:

[0023] S1 Sampling: The liquid medicine to be detected is extracted from the bath solution through the sampling module. First, the liquid medicine to be detected is circulated in the path of the filtration module -> defoaming module -> reflux module -> bath solution in sequence. After circulating for a certain time, the extracted liquid medicine to be detected is sent to the copper ion detection module.

[0024] S2 Copper ion detection: The copper ion concentration in the liquid medicine to be detected is detected by the copper ion detection module. After the detection is completed, the transfer liquid medicine is sent to the next step.

[0025] S3 Dilution: The transfer liquid medicine is diluted by the iron ion dilution module, and the iron ion concentration in the transfer liquid medicine is diluted to match the measurement range of the iron ion detection module.

[0026] S4 Iron ion detection: The diluted transfer liquid medicine is detected by the iron ion detection module, and then the actual iron ion concentration in the bath solution is calculated according to the dilution amount. After the detection is completed, the liquid medicine is sent to the liquid discharge module.

[0027] Before the step S2, a calibration step is further included.

[0028] PRS2.1, Prepare a standard module for the liquid medicine with known standard values. The liquid medicine with standard values has known standard values of copper ion concentration and iron ion concentration.

[0029] PRS2.2, The liquid medicine with standard values is detected through the steps S2, S3, and S4 in sequence to obtain the detected values of copper ion concentration and iron ion concentration.

[0030] PRS2.3, Compare the detected values of copper ion concentration and iron ion concentration with the standard values of copper ion concentration and iron ion concentration respectively. If the error range is greater than the error threshold, the copper ion detection module and the iron ion detection module are corrected using the standard values of copper ion concentration and iron ion concentration.

[0031] In the step S3, a step of quantitative dilution is further included. Before diluting the transfer liquid medicine, the transfer liquid medicine is divided into two parts. One part is sampled by the quantitative liquid addition module and then diluted to the measurement range of the iron ion detection module by the iron ion dilution module; the other part is directly sent to the liquid discharge module.

[0032] An on-line copper and iron ion analysis system and method for PCB via filling process chemicals. Through a detection line, the chemical solution after being detected by the copper ion detection module is further used for iron ion detection. In addition, multiple parallel sampling modules can be set up to sample different chemical solution tanks respectively, and the accuracy of the detection module can be corrected by using standard samples. The present invention can achieve one-time sampling and simultaneously detect copper ions or iron ions, realizing on-line monitoring of the chemical solutions in multiple tanks, eliminating the need for multiple manual samplings. It can avoid potential harm to the human body caused by the surrounding terrain and environment during sampling, save human resources, solve the problem of difficult employment in the general trend, shorten the sampling and analysis time, reduce the monitoring cost, exclude the influence of human factors in the data processing process, improve the detection efficiency and accuracy, and has wide application value for popularization. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the functional modules of the on-line copper and iron ion analysis system for PCB via filling process chemicals according to the present invention;

[0034] Figure 2 It is a flowchart of the on-line copper and iron ion analysis method for PCB via filling process chemicals according to the present invention;

[0035] Figure 3 It is a standard curve graph of copper ions in an embodiment of the present invention;

[0036] Figure 4 It is a standard curve graph of iron ions in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] Various specific embodiments of the present application will be described below with reference to the drawings forming a part of this specification. It should be understood that although terms indicating directions, such as "front", "rear", "upper", "lower", "left", "right", etc., are used in the present application to describe various example structural parts and elements of the present application, these terms are used only for the convenience of description and are determined based on the example orientations shown in the drawings. Since the embodiments disclosed in the present application can be arranged in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. Where possible, the same or similar reference numerals used in the present application refer to the same components.

[0038] As Figure 1 shown, an on-line copper and iron ion analysis system for PCB via filling process chemicals includes a sampling module, a copper ion detection module, an iron ion detection module, and a liquid discharge module;

[0039] The sampling module is used to extract the liquid medicine to be detected from the bath solution, achieving automatic sampling of the bath solution and avoiding the harm of chemical agents to the human body during manual sampling. At the same time, in order to reduce the errors caused by impurities and bubbles to the detection results, the sampling module also includes a filtering module and a defoaming module. After extracting the liquid medicine to be detected, the liquid medicine to be detected is first filtered through the filtering module to remove liquid oily impurities, suspended solids or flocculates, solid particle impurities, etc. in the liquid medicine to be detected, and then the defoaming module is used to eliminate the bubbles in the filtered liquid medicine to be detected, so as to reduce detection interference.

[0040] In addition, considering the possible influence of the residual liquid medicine in the pipeline of the sampling module on the detection results, the sampling module also includes a reflux module. The reflux module first sends the filtered and defoamed liquid medicine to be detected back to the bath solution, and after maintaining this circulating state for a certain period of time, the liquid medicine to be detected is sent into the copper ion detection module, further reducing detection interference.

[0041] At the same time, in order to improve the monitoring efficiency and achieve synchronous monitoring of multiple bath solutions, in the present invention, the sampling module is multi-channel, and the multi-channel sampling modules are arranged in parallel. Each sampling module extracts the liquid medicine to be detected from different bath solutions respectively; in this embodiment, there are two parallel sampling modules; the multi-channel sampling modules are controlled by a first switching module to transport the liquid medicine to be detected extracted by different sampling modules to the copper ion detection module.

[0042] In the present invention, the copper ion detection module and the iron ion detection module both use the principle of absorptiometry with a specific spectral wavelength to measure the concentrations of copper ions and iron ions. After fitting the signal value-concentration into an equation through experiments, the corresponding copper ion and iron ion concentrations are obtained according to the measured signal values. Because the range of the iron ion detection module is usually small during actual detection, the liquid medicine needs to be diluted before iron ion detection. The analysis system of the present invention also includes a third switching module and an iron ion dilution module. The iron ion dilution module is connected in parallel with the outlet side of the copper ion detection module to the third switching module. The third switching module quantitatively dilutes the liquid medicine and then sends it into the iron ion detection module for detection; the liquid medicine after iron ion detection is discharged into a waste liquid bucket for collection and can be processed by an external waste discharge pipeline.

[0043] Since iron ions need to be prevented from hydrolyzing under weak acid conditions, in order to ensure that the sample to be tested does not crystallize, the iron ion dilution module preferably uses a dilute acid solution for dilution. Taking environmental protection into account, the waste acid solution after the detection is completed is reduced. A quantitative liquid adding module is provided in the iron ion detection module. The medicinal liquid after the copper ion detection module has detected is divided into two parts. One part is sampled by the quantitative liquid adding module and then diluted to within the measurement range of the iron ion detection module by the iron ion dilution module; the other part is sent to the discharge module; during dilution, the liquid to be tested in the quantitative sampling module is first pushed into the mixer for dilution by a quantitative dilute acid solution controlled by the third switching module, and then further added with a quantitative dilute acid solution to dilute the sample to be tested to within the design range of the iron ion detection module. After the final detection is completed, the waste liquid is sent to the discharge module; in the present embodiment, the quantitative sampling in the iron ion detection is to achieve quantitative volume by a corrosion-resistant hose of a specific length and inner diameter.

[0044] In order to further improve the accuracy of the detection of the present invention, the analysis system also includes a standard solution module and a second switching module. The standard solution module contains a drug solution with a measured standard value, and the standard solution module is connected to the second switching module in parallel with the first switching module. When the online analysis system monitors for a period of time and the detection results may be inaccurate, the drug solution in the standard solution module is sent to the detection module through the second switching module, and the detection values of the copper ion detection module and the iron ion detection module are compared with the standard values to determine the detection error of the current analysis system. Under normal circumstances, when the deviation exceeds 5%, it is necessary to revise the signal value-concentration equation using the standard value to reduce the system error.

[0045] For the detection of copper ions, in order to reduce the impact of residues in the pipeline on the detection results and reduce system errors, a copper ion dilution module is also connected in parallel to the liquid inlet side of the copper ion detection module, and a quantitative dilute acid solution is pushed for flushing each time.

[0046] like Figure 2 As shown, an online copper and iron ion analysis method for PCB hole filling process liquid is carried out in the following steps:

[0047] A method for online copper and iron ion analysis of PCB hole filling process liquid comprises the following steps:

[0048] S1 sampling: The drug solution to be tested is extracted from the tank liquid through the sampling module. The drug solution to be tested is first circulated in the path of filtration module -> defoaming module -> reflux module -> tank liquid. After a certain period of circulation, the extracted drug solution to be tested is sent to the copper ion detection module. After a certain period of reflux, the sampling pipeline is rinsed and the sample to be tested is collected, reducing subsequent analysis errors.

[0049] In order to improve the efficiency of online monitoring, in the sampling step, multiple independent and parallel sampling modules are set up and controlled by the first switching module. Each sampling module separately extracts the liquid medicine to be detected from different bath solutions, and conveys the liquid medicine to be detected extracted by different sampling modules to the copper ion detection module;

[0050] S2 Copper ion detection: When detecting, the principle of absorptiometry with a specific spectral wavelength is adopted, and a copper ion detector is used for detection to obtain corresponding signal values. The results are obtained through software system processing according to the corresponding relationship between the signal values and the concentrations; the copper ion concentration in the liquid medicine to be detected is detected by the copper ion detection module. After the detection is completed, the transferred liquid medicine is sent to the next step; in order to reduce the influence of the residue in the pipeline on the detection results and reduce the system error, this step also includes the step of using the copper ion dilution module to quantitatively push the dilute acid solution to flush the pipeline before the copper ion detection module detects, ensuring that the quantitatively extracted liquid medicine to be detected can be accurately pushed into the copper ion detection module;

[0051] S3 Dilution: The transferred liquid medicine is diluted by the iron ion dilution module to dilute the iron ion concentration in the transferred liquid medicine to match the measurement range of the iron ion detection module; considering that the iron ion concentration in the bath solution may be higher than the measurement range of the iron ion detection module; at the same time, since iron ions can prevent hydrolysis only under weak acid conditions, in order to ensure that no crystallization occurs in the test sample, dilute acid is preferably used for dilution. Therefore, considering the factor of the environmental pollution caused by the acid solution, the amount of dilute acid used for dilution is reduced to a certain extent. This step also includes the step of quantitative dilution. Before diluting the transferred liquid medicine, the transferred liquid medicine is divided into two parts. One part is sampled by the quantitative liquid adding module and then diluted to the measurement range of the iron ion detection module by the iron ion dilution module; the other part is directly sent to the drainage module;

[0052] S4 Iron ion detection: When detecting, the principle of absorptiometry with a specific spectral wavelength is adopted, and a copper ion detector is used for detection to obtain corresponding signal values. The results are obtained through software system processing according to the corresponding relationship between the signal values and the concentrations; the diluted transferred liquid medicine is detected by the iron ion detection module, and then the actual iron ion concentration in the bath solution is calculated according to the dilution amount. After the detection is completed, the liquid medicine is sent to the drainage module.

[0053] In the present invention, in order to ensure the accuracy of detection, a calibration step is further included before step S2,

[0054] PRS2.1, Prepare a standard module for the liquid medicine with known standard values. The liquid medicine with standard values has known standard values of copper ion concentration and iron ion concentration;

[0055] PRS2.2, Pass the liquid medicine with standard values through steps S2, S3, and S4 for detection in sequence to obtain the copper ion concentration detection value and the iron ion concentration detection value;

[0056] PRS 2.3 compares the detected values of copper ion concentration and iron ion concentration with the standard values of copper ion concentration and iron ion concentration respectively. If the error range is greater than the error threshold, the copper ion detection module and iron ion detection module are corrected using the standard values of copper ion concentration and iron ion concentration.

[0057] The actual detection is as follows:

[0058] The copper ion concentration range of the bath solution is 45 - 55 g / L, the iron ion concentration is 20 - 30 g / L, the detection range of the copper ion detector is 0 - 80 g / L, and the detection range of the iron ion detector is 0 - 10 g / L. Tables 1 and 2 below are the parameters of the samples taken during the analysis process, and finally the following Figure 3 、 4 curve graph is obtained:

[0059]

[0060] Table 1

[0061]

[0062] Table 2

[0063] According to the corresponding relationship between the signal value and the concentration in the copper and iron ion standard curves and the signal values detected during the actual detector analysis, the specific copper ion and iron ion concentrations of the bath solution are calculated as shown in Table 3 below:

[0064]

[0065] Table 3

[0066] Although the present application will be described with reference to the specific embodiments shown in the accompanying drawings, it should be understood that the PCB via filling process chemical solution on-line copper and iron ion analysis system and method of the present application can have many variations without departing from the spirit and scope and background of the teachings of the present application. Those of ordinary skill in the art will also realize that there are different ways to change the parameters in the embodiments disclosed in the present application, all of which fall within the spirit and scope of the present application and the claims.

Claims

1. A PCB hole filling process liquid online copper and iron ion analysis system, characterized in that: Includes the following modules: The sampling module is used to extract the drug solution to be tested from the tank liquid; A copper ion detection module receives the drug solution to be tested extracted by the sampling module and detects the copper ion concentration in the drug solution; The iron ion detection module receives the liquid medicine detected by the copper ion detection module and detects the iron ion concentration in the liquid medicine: The drainage module is used to collect and discharge the discarded liquid medicine after the test; Also includes: A third switching module and an iron ion dilution module, wherein the iron ion dilution module and the liquid outlet side of the copper ion detection module are connected in parallel to the third switching module, and the third switching module quantitatively dilutes the liquid and then sends it to the iron ion detection module for detection; The iron ion detection module is provided with a quantitative liquid adding module. The medicinal liquid detected by the copper ion detection module is divided into two parts. One part is sampled by the quantitative liquid adding module and then diluted by the iron ion dilution module to the measurement range of the iron ion detection module; the other part is sent to the liquid discharge module.

2. The PCB hole filling process liquid medicine online copper and iron ion analysis system according to claim 1, characterized in that: The sampling module includes a filtering module and a defoaming module, wherein The filtering module is used to extract the drug solution to be tested from the tank liquid and filter out liquid oily impurities, suspended matter or flocculent matter, solid particles and other impurities therein; The defoaming module is used to sample the drug solution to be tested after filtration and eliminate bubbles therein to reduce detection interference.

3. The PCB hole filling process liquid medicine online copper and iron ion analysis system according to claim 2, characterized in that: It also includes a reflux module, which first sends the filtered and defoamed liquid to be tested back to the tank liquid, and then sends the liquid to be tested into the copper ion detection module after a certain period of time.

4. The PCB hole filling process liquid online copper and iron ion analysis system according to claim 2, characterized in that: The sampling modules are multi-channel, and the multi-channel sampling modules are arranged in parallel, and each sampling module extracts the drug solution to be tested from a different tank liquid; The PCB hole filling process liquid online copper and iron ion analysis system also includes: The first switching module is connected to the multi-channel sampling modules at the same time and switches to transport the to-be-detected medicinal solutions extracted by different sampling modules to the copper ion detection module.

5. The PCB hole filling process liquid medicine online copper and iron ion analysis system as claimed in claim 4, characterized in that, Also includes: The standard solution module contains a solution with a measured standard value; a second switching module, wherein the standard solution module is connected in parallel with the first switching module; The drug solution in the standard solution module is sent to the copper ion detection module through the second switching module.

6. A method for online copper and iron ion analysis of PCB hole filling process liquid, characterized in that: The following steps are involved: S1 sampling: extract the test liquid from the tank liquid through the sampling module, first circulate the test liquid in the path of filtration module -> defoaming module -> reflux module -> tank liquid, and then send the extracted test liquid to the copper ion detection module after a certain period of circulation; S2 copper ion detection, using the copper ion detection module to detect the copper ion concentration in the test solution, after the test is completed, the transfer solution is sent to the next step; S3 dilution: Use the iron ion dilution module to dilute the transfer solution to match the iron ion concentration of the iron ion detection module; S4 iron ion detection: Use the iron ion detection module to detect the diluted transfer liquid, and then calculate the actual iron ion concentration in the tank liquid based on the dilution amount. After the detection is completed, the liquid is sent to the drainage module.

7. The online copper and iron ion analysis method for PCB hole filling process liquid medicine as claimed in claim 6, characterized in that: The step S2 also includes a calibration step, PRS2.1, prepare a standard module with a standard value solution having known copper ion concentration and iron ion concentration; PRS2.2, test the standard value solution in steps S2, S3, and S4 in sequence to obtain the copper ion concentration test value and the iron ion concentration test value; PRS2.3, respectively compare the copper ion concentration detection value and the iron ion concentration detection value with the copper ion concentration standard value and the iron ion concentration standard value. If the error range is greater than the error threshold, the copper ion concentration standard value and the iron ion concentration standard value are used to correct the copper ion detection module and the iron ion detection module.

8. The method for analyzing copper and iron ions in an online PCB hole-filling process solution as claimed in claim 6, wherein: The step S3 also includes a quantitative dilution step. Before diluting the transfer liquid, the transfer liquid is divided into two parts. One part is sampled by the quantitative liquid addition module and then diluted by the iron ion dilution module to within the measurement range of the iron ion detection module; the other part is directly sent to the liquid discharge module.

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