Device and method for monitoring precipitation stability of chemical copper plating on line

Abstract

The invention belongs to the technical field of surface metal of printed circuit boards, and particularly provides a device and a method for monitoring precipitation stability of chemical copper plating on line, and the device comprises a composite electrode, a precipitation hanging piece, a millivoltmeter, a processor, an alarm and a power supply module for supplying power to the whole device; one end of the composite electrode and one end of the precipitation hanging piece are arranged in chemical copper plating liquid medicine, the other end of the composite electrode is connected to a first input end of the millivoltmeter, the other end of the precipitation hanging piece is connected to a second input end of the millivoltmeter, an output end of the millivoltmeter is connected to an input end of the processor, and an output end of the processor is connected to the alarm. According to the invention, a polarization reaction and precipitation potential monitoring structure of metal is utilized to realize real-time monitoring of the precipitation state of chemical copper plating. Through the device, the product quality can be more effectively guaranteed, and the quality risk is reduced. Meanwhile, the device has the advantages of simplicity and convenience in operation, accuracy in monitoring, quick response and the like, and can be widely applied to the printed circuit board manufacturing industry.

Description

Technical Field

[0001] The invention belongs to the technical field of surface metal of printed circuit boards, and in particular relates to a device and method for online monitoring of chemical copper plating precipitation stability. Background Art

[0002] Chemical copper plating is a process in the manufacture of printed circuit boards, usually also called copper deposition or pore plating, which is a self-catalytic redox reaction. First, it is treated with an activator to adsorb a layer of active particles on the surface of the insulating substrate, usually metal palladium particles-copper ions. First, it is reduced on these active metal palladium particles, and these reduced metal copper crystal nuclei themselves become the catalytic layer of copper ions, so that the reduction reaction of copper continues on the surface of these new copper crystal nuclei. However, the effect of the precipitated copper crystal nuclei directly determines whether the product is qualified. Therefore, monitoring the precipitation of copper crystal nuclei has become an indispensable part of the process.

[0003] The existing monitoring method is to regularly put in the backlight board (the so-called backlight board is a resin copper-clad board after mechanical drilling) for monitoring. Its working principle is: when the backlight board is made, the resin of the same material as the product is used as the core material. At the same time, the hole density of the backlight board is much greater than the hole density of the product. When flowing, it is carried out under the same processing conditions as the product to perform online flow, and the copper deposition effect in the hole is monitored by simulating a more stringent state than the product. Among them, the flow method is: the backlight board and the product flow into the chemical copper wire body at the same time, and the slice of the hole position of the outflowing backlight board is enlarged. After enlarging several times, the precipitation effect of the copper crystal nucleus is observed by backlight. This method is used to judge whether the precipitation of copper crystal nuclei in the holes of the products produced during the period is normal. Problems with the existing approach: This method of monitoring using the backlight board is a regular monitoring method, usually once every 3 to 6 hours, and it is impossible to achieve real-time monitoring. That is to say, if there is abnormal precipitation of copper crystal nuclei in a certain period of time, it cannot be guaranteed to be discovered in time. Such a monitoring mode still brings great quality risks. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a device and method for online monitoring of chemical copper plating precipitation stability to solve the above-mentioned technical problems.

[0005] In a first aspect, the present invention provides an apparatus for online monitoring of chemical copper plating precipitation stability, comprising a composite electrode, a precipitation hanging sheet, a millivoltmeter, a processor, an alarm, and a power module for powering the entire apparatus; One end of the composite electrode and one end of the precipitation hanging piece are placed in the chemical copper plating solution, the other end of the composite electrode is connected to the first input end of the millivoltmeter, the other end of the precipitation hanging piece is connected to the second input end of the millivoltmeter, the output end of the millivoltmeter is connected to the input end of the processor, and the output end of the processor is connected to the alarm.

[0006] A further improvement of the technical solution is that the precipitation hanging sheet includes a copper sheet and resin sheets arranged on both sides of the copper sheet, the resin sheet is adhered to the copper sheet, and the copper sheet is connected to the second input terminal of the millivoltmeter through a wire.

[0007] A further improvement of the technical solution is that the alarm adopts an audible and visual alarm of model LTE-1101J.

[0008] A further improvement of the technical solution is that the processor includes a monitoring box, a microprocessor and a display, the display is installed on one side of the monitoring box, the microprocessor is arranged in the monitoring box, and the display is connected to the output end of the microprocessor; the alarm is installed above the monitoring box.

[0009] A further improvement of the technical solution is that the microprocessor adopts a single chip microcomputer of model STM32F103RBT6.

[0010] In a second aspect, the present invention provides a method for online monitoring of chemical copper plating precipitation stability, the method being applicable to the device for online monitoring of chemical copper plating precipitation stability described in any one of the above items, comprising: Place one end of the composite electrode and one end of the precipitation hanging piece in a chemical copper plating solution; The potential values ​​of the composite electrode and the precipitation hanging piece are respectively measured in real time by a millivoltmeter and uploaded to the processor; The processor calculates the potential difference between the composite electrode and the precipitation hanging sheet according to the received potential value, and displays it in real time through the display; The processor determines whether the calculated potential difference is within a preset potential difference range; If not, the processor controls the alarm to give an abnormal alarm.

[0011] The beneficial effect of the present invention is that the present invention utilizes the polarization reaction of the metal and the precipitation potential monitoring structure to realize real-time monitoring of the chemical copper plating precipitation state. Through the device, product quality can be more effectively guaranteed and quality risks can be reduced. At the same time, the device has the advantages of simple operation, accurate monitoring, rapid response, etc., and can be widely used in the printed circuit board manufacturing industry.

[0012] In addition, the invention has a reliable design principle, a simple structure and a very broad application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1is a schematic flow chart of a method according to an embodiment of the present invention.

[0015] Figure 2 is a schematic block diagram of a system according to an embodiment of the present invention.

[0016] 110 is a composite electrode, 120 is a precipitation hanging sheet, 130 is a millivoltmeter, 140 is a processor, and 150 is an alarm. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0019] like Figure 1 As shown, the present invention provides an online monitoring device for the stability of chemical copper plating precipitation, comprising a composite electrode, a precipitation hanging piece, a millivoltmeter, a processor, an alarm and a power module for powering the entire device; one end of the composite electrode and one end of the precipitation hanging piece are placed in the chemical copper plating solution, the other end of the composite electrode is connected to the first input end of the millivoltmeter, the other end of the precipitation hanging piece is connected to the second input end of the millivoltmeter, the output end of the millivoltmeter is connected to the input end of the processor, and the output end of the processor is connected to the alarm. The alarm adopts an acousto-optic alarm model LTE-1101J.

[0020] Specifically, the precipitation hanging sheet includes a copper sheet and resin sheets arranged on both sides of the copper sheet, the resin sheet is adhered to the copper sheet, and the copper sheet is connected to the second input terminal of the millivoltmeter through a wire. The selection of the copper sheet model and the resin sheet model is determined by the product to be produced.

[0021] The processor includes a monitoring box, a microprocessor and a display, wherein the display is installed on one side of the monitoring box, the microprocessor is arranged in the monitoring box, and the display is connected to the output end of the microprocessor; the alarm is installed above the monitoring box. Among them, the microprocessor adopts a single chip microcomputer of model STM32F103RBT6.

[0022] Figure 2 is a schematic flow chart of a method according to an embodiment of the present invention. Figure 2 The execution subject may be a device for online monitoring of chemical copper plating precipitation stability. According to different requirements, the order of the steps in the flow chart may be changed, and some may be omitted.

[0023] like Figure 2 As shown, the method includes: Step 210, placing one end of the composite electrode and one end of the precipitation hanging sheet in a chemical copper plating solution; Step 220, measuring the potential values ​​of the composite electrode and the precipitation hanging sheet in real time by a millivoltmeter, and uploading them to the processor; Step 230, the processor calculates the potential difference between the composite electrode and the precipitation hanging sheet according to the received potential value, and displays it in real time through the display; Step 240, the processor determines whether the calculated potential difference is within a preset potential difference range; if not, go to step 250; Step 250: The processor controls the alarm to generate an abnormality alarm.

[0024] Specifically, the polarization reaction of the metal is used to measure the precipitation potential value of the copper crystal nucleus. When the current passes through the electrode, the electrode potential will deviate from its equilibrium potential, resulting in polarization. When copper is precipitated on the cathode, it is necessary to make the electrode potential relative to the equilibrium potential negatively shift to a preset value before it can precipitate. Therefore, by monitoring the numerical changes in the electrode potential, the precipitation state of the copper crystal nucleus can be judged. By setting the optimal monitoring value, the device of the present invention can provide real-time feedback on the online copper precipitation state. When the potential value deviates from the set value, the device will sound an alarm to prompt the operator to handle it in time.

[0025] Although the present invention has been described in detail with reference to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A device for online monitoring of chemical copper plating precipitation stability, characterized in that: It includes a composite electrode, a precipitation hanging sheet, a millivoltmeter, a processor, an alarm and a power module for supplying power to the entire device; One end of the composite electrode and one end of the precipitation hanging piece are placed in the chemical copper plating solution, the other end of the composite electrode is connected to the first input end of the millivoltmeter, the other end of the precipitation hanging piece is connected to the second input end of the millivoltmeter, the output end of the millivoltmeter is connected to the input end of the processor, and the output end of the processor is connected to the alarm.

2. The device for online monitoring of chemical copper plating precipitation stability according to claim 1, characterized in that: The precipitation hanging sheet comprises a copper sheet and resin sheets arranged on both sides of the copper sheet, the resin sheets are adhered to the copper sheet, and the copper sheet is connected to the second input terminal of the millivoltmeter through a wire.

3. The device for online monitoring of chemical copper plating precipitation stability according to claim 1, characterized in that: The alarm uses an audible and visual alarm model LTE-1101J.

4. The device for online monitoring of chemical copper plating precipitation stability according to claim 1, characterized in that: The processor comprises a monitoring box, a microprocessor and a display, wherein the display is installed at one side of the monitoring box, the microprocessor is arranged in the monitoring box, and the display is connected to the output end of the microprocessor; and the alarm is installed above the monitoring box.

5. The device for online monitoring of chemical copper plating precipitation stability according to claim 4, characterized in that: The microprocessor used is the STM32F103RBT6 microcontroller.

6. A method for online monitoring of chemical copper plating precipitation stability, the method being applicable to the device for online monitoring of chemical copper plating precipitation stability as claimed in any one of claims 1 to 5, characterized in that: include: Place one end of the composite electrode and one end of the precipitation hanging piece in a chemical copper plating solution; The potential values ​​of the composite electrode and the precipitation hanging piece are respectively measured in real time by a millivoltmeter and uploaded to the processor; The processor calculates the potential difference between the composite electrode and the precipitation hanging sheet according to the received potential value, and displays it in real time through the display; The processor determines whether the calculated potential difference is within a preset potential difference range; If not, the processor controls the alarm to give an abnormal alarm.

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