JP3213113B2 - Automatic solder plating solution management system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic solder plating solution management apparatus, and more particularly to an automatic solder plating solution management apparatus capable of automatically controlling the composition concentration of a solder plating solution during a solder plating process.

[0002]

2. Description of the Related Art Recently, solder plating is often performed on electronic components. Solder plating baths for performing the solder plating include a boric acid bath and an organic sulfonic acid bath. Solder plating obtained in a boric acid bath has good physical properties of the resulting film and is often used.However, high current density and good quality plating cannot be obtained, wastewater treatment is difficult, or wastewater standards are strict. For this reason, organic sulfonic acid baths have recently been used. Thus, in order to obtain a conductive solder plating film having an adhesive function necessary for an electronic component such as a lead frame, it is necessary to control the composition concentration of the solder plating bath. In this case, the composition to be controlled is a free acid that gives conductivity to the plating bath, Sn ²⁺ and Pb ²⁺ that constitute the plating film, and additives that are used to obtain a plating film with stable quality. It is necessary to maintain those densities at the set control density and standard control width. In order to control the composition concentration of the plating bath with the standard control width, it is necessary to accurately analyze the composition concentration of the solder plating solution during the solder plating process, but conventionally, it takes a lot of time to manually analyze are doing.

Further, the calculation and replenishment of the replenishment amount of the deficient component on the basis of the analyzed composition concentration have all been performed manually.

[0004]

However, in the above-mentioned conventional analysis method, Sn ²⁺ , free acid, Pb ²⁺
There is a problem that three containers for analysis have to be used and the analysis has to be performed manually in order to analyze the water.
In addition, in the case of the organic sulfonic acid bath, there is a problem that the concentration of the additive must be separately analyzed.

Further, there is a problem that the calculation and the replenishment of the replenishment amount of the deficient component must be manually performed based on the composition concentration analyzed as described above.

The present invention has been made in view of the above-mentioned circumstances, and has been developed in consideration of the S plating of the solder plating solution during the solder plating process.
It is an object of the present invention to provide a solder plating solution automatic management device capable of analyzing n ²⁺ , free acid, Pb ²⁺ and additive concentration and calculating a replenishing amount of each component based on the analysis result. .

[0007]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, an automatic solder plating solution management apparatus according to the present invention always takes out a solder plating solution from a solder plating bath during a solder plating process and removes the solder plating solution from the bath. A circulating bath for analyzing the solder plating solution, which was returned to the above condition, a container for analysis capable of analyzing the concentrations of Sn ²⁺ , free acid, and Pb ^{2+ in} the solder plating solution; The installed electrode, an additive concentration analysis unit capable of analyzing the additive concentration, a sampling mechanism for sampling the solder plating solution from the solder plating solution analyzing circulation tank to the analysis container, and the respective concentration analysis A reagent supply unit for supplying various reagents necessary for the analysis to the analysis container, and washing for washing the analysis container, the electrode, and the additive concentration analysis unit during the respective concentration analysis steps. A liquid supply unit, an arithmetic and control unit that controls each of the device units and calculates a replenishment amount of each component from a result obtained by the concentration analysis, and a display device that displays the analysis result and the replenishment amount. It is characterized by having.

[0008]

According to the present invention having the above-described structure, the solder plating solution is constantly guided from the solder plating bath during the solder plating process to the circulation bath for analyzing the solder plating solution, and is sampled from the circulation bath for analyzing the solder plating solution by the sampling mechanism. The solder plating solution is sampled and transferred to a container for analysis.
After quantitatively analyzing any one component of n ²⁺ , free acid, and Pb ²⁺ , the cleaning liquid supply unit is operated to wash the analysis container and the electrodes. To repeat the above operation
> Analyze the other two components, and perform quantitative analysis of Sn ²⁺ , free acid, and Pb ²⁺ in one analysis container. Also,
The additive concentration analysis section analyzes the additive concentration. On the other hand, each analysis result is input to the arithmetic and control unit, and the replenishment amount of each component is obtained, and the replenishment amount and each analysis result are displayed on the display device.

According to one aspect of the present invention, the replenishment pump installed in the replenishment tank is controlled based on the calculated replenishment amount, and the insufficient component can be replenished to the solder plating tank. Further, the analysis result, the supply amount, and the like can be sent to an external computer.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic solder plating solution management apparatus according to the present invention will be described below with reference to FIG. The automatic solder plating solution management apparatus includes a housing B (indicated by a two-dot chain line), and a circulation bath 2 for analyzing a solder plating solution is installed in the housing B. The supply pipe 3 is connected to the solder plating tank 1 and the circulation tank 2 for analyzing the solder plating solution during the solder plating process.
are connected by a and the return pipe 3b, the sampling pump circulation the supply pipe 3a P ₁ and valve V ₁
There are installed by operating the circulation sampling pump P ₁ always plating tank 1 the solder which is taken out from the solder plating bath 1 in the solder plating step the plating solution analyzing circulation tank 2 solder the solder plating solution To return to.

An analysis vessel 4 is installed adjacent to the solder plating solution analysis circulation tank 2, and a PH electrode 5 and an oxidation-reduction electrode 6 are installed in the analysis vessel 4. A light emitting unit 7a and a light receiving unit 7b are provided outside the analysis container 4.
Is installed. A magnetic stirrer 8 is installed outside the bottom of the analysis container 4 so that the liquid in the analysis container 4 is stirred. Further, the bottom of the analysis container 4 waste pipe 3c is connected, the solenoid valve V ₂ is interposed in the pipe 3c.

A sampling vessel 10 is provided for sampling the solder plating solution from the solder plating solution analyzing circulation tank 2 and transferring it to the analysis vessel 4, and the sampling vessel 10 is provided with a sampling mechanism (not shown). As a result, the solder plating solution can be moved between the analysis circulation tank 2 and the analysis vessel 4 as indicated by a broken line.

[0013] The sampling container 10 is connected sampling pipe 3d is the sampling pump P ₂ is connected to the pipe 3d. Thus, after inserting the sampling vessel 10 solder plating solution analyzing circulation tank 2 by the sampling mechanism, by operating the sampling pump P ₂ sucks a predetermined amount of solder plating solution,
Thereafter, the sampling container 10 is moved to the analysis container 4, and the solder plating solution is transferred from the sampling container 10 into the analysis container 4.

When the sampling vessel 10 reaches the position of the analysis vessel 4, it is connected to the pure water pipe 3e. Its end with the pure water pipe 3e valve V ₃ and the pure water pump P ₇ is installed is connected to the pure water tank T _1, after the sampling container 10 was discharged solder plating solution, sampling Container 1
The solder plating solution adhering to the wall of No. 0 is cleaned and removed with pure water.

In the analysis container 4, a suction supply pipe 3f is provided.
There is inserted, the pipe 3f is connected to the additive concentration analyzer 12 via the three-way valve V _4, it is further connected to a suction pump P ₃ the pipe 3f via the three-way valve V ₅ . Incidentally, NO port of the three-way valve V ₅ is waste pipe 3c
It is connected to the. The additive concentration analyzing section 12 includes a flow cell 12a, a light emitting section 12b, and a light receiving section 12c.

A cleaning reagent tank T ₂ , a titration reagent tank T ₃ and a standard solution reagent tank T ₄ are provided adjacent to the pure water tank T ₁ . Although FIG. 1 shows each of the reagent tanks T _{1 to} T ₄ for simplicity, each is actually composed of a plurality of reagent tanks. The reagent tank T ₂ is inserted reagents pipe 3g reagent pump P ₄ is installed, titrated pipe 3h the titration pump P ₅ is installed is inserted into the titration reagent tank T _3, further standard solution for standard solution pipe 3i standard pump P ₆ is installed in the reagent tank T ₄ is inserted.

[0017] Solder plating solution automatic management apparatus, each apparatus (the electrodes 5 and 6 described above, permeability measuring instrument 7, a sampling mechanism, a pump P ₁ to P _7, the valve V ₂ ~V ₅ and additive concentration analyzer 12 ) And an arithmetic control unit 14 for calculating the replenishment amount of each component from the result obtained by the concentration analysis, and a display device 15 for displaying the analysis result and the calculated replenishment amount.

Next, a description will be given of a method for managing a solder plating solution by the automatic solder plating management apparatus configured as described above. Circulation sampling pump P ₁ is in operation at all times, the solder plating solution is removed from the solder plating bath 1 is again turned back to the solder plating tank 1 circulates the solder plating solution analyzing circulation tank 2. First, after inserting the sampling vessel 10 in a solder plating solution analyzing circulation tank 2, a solder plating solution and a predetermined amount sucked into the sampling container 10 by operating the sampling pump P _2, then the sampling mechanism again operates Then, the solder plating solution in the sampling container 10 is discharged to the position of the analysis container 4 and transferred to the analysis container 4. At this time, although solder plating solution on the wall of the sampling vessel 10 is attached, together with the Operating the pure water pump P ₇ by opening the valve V _3, pure water through a pipe 3e in the sampling container 10 The inside of the sampling container 10 is supplied and washed, and all the solder plating solution adhering to the sampling container 10 is transferred to the analysis container 4.

Next, by switching the three-way valve V ₄ is operated with pure water pump P _7, pure water branch pipe 3j, and supplies to the analysis container 4 via a three-way valve V ₄ and the pipe 3f, the solder The plating solution is diluted to generate a predetermined amount of the analysis solution. Then, by operating the reagent pump P _4, the analysis of Sn ²⁺ performs titration titration pump P ₅ is operated after the addition of the titration reagent. At this time, oxidation / reduction titration with a specified iodine solution is used for the analysis of Sn ²⁺ , and the oxidation / reduction electrode 6 is used as a sensor for detecting the end point. After the quantitative analysis of Sn ²⁺ is completed by this titration, the analysis container 4 and the electrodes 5 and 6 are washed. That is, the reagent pump P ₄ is operated to set the reagent tank T
The predetermined cleaning reagent from ₂ drained after supplying the analysis container 4, then valve V after supplying pure water washed with pure water by running pure water pump P ₇ to the analysis vessel 4 Open ₂ to drain pure water.

Next, the sampling mechanism is operated again to sample a new solder plating solution (predetermined amount) by the sampling container 10 and transfer it to the analysis container 4.
Details of this sampling are omitted because they are performed in the same manner as described above. And operate the pure water pump P ₇ supplying pure water to the analysis vessel 4, to produce a predetermined amount of analysis is diluted solder plating solution. Then, a quantitative analysis of the free acid was titrated by running titration pump P _5. At this time, neutralization titration with a prescribed sodium hydroxide solution is used for the analysis of free acid, and the PH electrode 5 is used as an end point detection sensor.

After the analysis of free acid is completed by this titration, the analysis container 4 and the electrodes 5 and 6 are washed. That reagent pump P ₄ is operated to drain after supplying from the reagent tank T ₂ a predetermined cleaning reagent to the analysis vessel 4, perform washing with pure water and then using a pure water pump P _7.

When the analysis of the free acid is completed through the above steps, the sampling mechanism is operated again, and a predetermined amount of the solder plating solution is sampled from the circulation bath 2 for analyzing the plating solution by the analysis container 4, and the analysis container 4 Transfer to And operate the pure water pump P ₇ supplying pure water to the analysis vessel 4, to produce a predetermined amount of analysis is diluted solder plating solution. Next, Pb was titrated with a titration pump P ₅ is operated after the addition of the titration reagent not operate the reagent pump P ₄
Perform quantitative analysis of ²⁺ . In this case, the analysis of Pb ²⁺ provisions E
A chelate photometric titration with a DTA solution is used, and a transmittance measuring device 7 in a specific wavelength range is used as a detection sensor for an end point. After the titration is finished, after draining perform the supply of cleaning reagent by operating the reagent pump P _4, perform washing with pure water by running pure water pump P _7.

Through the above steps, one analysis container 4
Sn²⁺, Free acid, Pb²⁺After performing the analysis of
Perform a degree analysis. In this additive analysis process, first, a pure water pump
P₇ To operate the pipe 3j and the three-way valve V _Four And pipe 3f
A predetermined amount of pure water was put into the analysis container 4 through
Later, the pure water pump P again₇ To separate a specified amount of pure water.
Put in the analysis container 4. And the suction pump P_Three Operated
Pure water into the flow cell 12a of the additive concentration analyzer 12.
Guide and absorbance by the light emitting part 12b and the light receiving part 12c.
Measure, and set the absorbance of this pure water to zero. Drain this pure water
After watering, operate the sampling mechanism to sample
A predetermined amount of solder plating solution is sampled in
And transfer it to the container 4 for analysis. And the pure water pump P₇ To
Operate and supply pure water to the container 4 for analysis and solder plating
The solution is diluted to generate a predetermined amount of the analysis solution.

Next, running the suction pump P ₃ guides the analysis solution into the flow cell 12a of the additive concentration analyzer 12, after measuring the absorbance by the light emitting unit 12b and the light receiving unit 12c, analytical vessel analysis liquid 4 and the additive concentration analysis unit 12 is drained. Then, pure water is supplied from the pure water pump P ₇ to supply the analysis container 4, the electrodes 5 and 6, and the additive concentration analyzer 12.
Wash. Thereafter, the analysis container 4 and the like are washed with hydrochloric acid and pure water.

The arithmetic and control unit 14 calculates the replenishment amount of each component and the integrated replenishment amount based on the analysis result obtained by the above-described method. The values are displayed on the display device 15. Then, on the basis of the calculated supply amount, and controls the supply pump P ₈ installed in supply tank 16 to replenish the plating tank 1 the solder shortage components. In addition, the arithmetic and control unit 14 transmits the analysis result, the supply amount and the calculated supply amount to the external computer 17.

After the above-described analysis step is repeated a predetermined number of times, a chemical solution cleaning is performed to remove the analysis products attached to the analysis container 4, the electrodes 5 and 6 in the analysis container 4, and the additive concentration analyzer 12. Perform a cleaning step. This washing step
Operate the reagent pump P ₄ supplies cleaning reagent to each washing portion from the reagent tank T ₂ by a predetermined time (e.g. 60 minutes)
After immersion, drained, repeated several times washed with pure water by running pure water pump P _7.

When the above analysis of Sn ²⁺ , free acid, Pb ²⁺ , and additive concentration is repeated a predetermined number of times, PH calibration and / or additive calibration becomes necessary. Agent calibration is also possible. Next, the PH calibration and the additive calibration will be described. After draining the liquid which initially remains in the analysis container 4 placed on the analysis vessel 4 PH7 standard solution of a predetermined amount by operating the standard pump P _6. Next, this solution is drained, and a predetermined amount of the PH7 standard solution is again put into the analysis container 4, the PH is measured, and the calibration of the PH7 is completed.

After the waste liquid is washed with pure water, a predetermined amount of PH4 standard solution is put into the analysis container 4 this time. After draining, a predetermined amount of the PH4 standard solution is put into the analysis container 4 again, the pH is measured, and the PH calibration is completed. Finally, after the liquid is drained, pure water washing is performed.

On the other hand, the additive calibration step is a pure water pump P ₇
Put predetermined amount of pure water to the analysis vessel by running, was placed pure water drainage was later again a predetermined amount to the analysis vessel 4, the additive concentration of pure water by operating the suction pump P ₃ It leads to the analysis unit 12. Then, after measuring the absorbance of the pure water, the water is drained. This time, a predetermined amount of the standard solution is supplied to the standard solution pump P _6.
Is operated and put into the analysis container 4. And by running pure water pump P ₇ supplying pure water to the analysis vessel 4 to produce a liquid of a predetermined amount by diluting the standard solution. Then, this solution is led to the additive concentration analyzer 12 to measure the absorbance, and a calibration curve is created. Finally, after draining the liquid, the reagent pump P
₄ to operate the specified amount of washing reagent for additive concentration analysis 1
2 guides, performing pure water cleaning by running pure water pump P ₇ After waste.

In the embodiment described above, Sn ²⁺ ,
Although an example has been described in which the analysis of the solder plating solution is performed in the order of free acid, Pb ²⁺ , and the concentration of the additive, the composition concentrations can be analyzed without being limited to this order. Further, the embodiment in which the present invention is applied to an organic sulfonic acid bath has been described. However, the present invention is of course applicable to a boric acid bath.

[0031]

As described above, according to the present invention, the solder plating solution during the solder plating step is sampled and transferred to an analysis container, and a predetermined component is quantitatively analyzed.
By sequentially repeating washing after analysis, Sn ²⁺ , free acid, and Pb ²⁺ can be analyzed in one analysis container, and the additive concentration can be analyzed in the additive concentration analysis section. it can. Then, the replenishment amount of each component can be automatically obtained based on these analysis results. Therefore, according to the present invention, all the components of the solder plating bath composed of the organic sulfonic acid bath can be automatically managed.

Further, according to one aspect of the present invention, the replenishing pump installed in the replenishing tank can be controlled based on the calculated replenishing amount, and the insufficient component can be automatically replenished to the solder plating tank.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of an automatic solder plating solution management apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder plating tank 2 Solder plating solution analysis circulation tank 3 Piping 4 Analysis container 5 PH electrode 6 Redox electrode 7 Permeability measuring device 8 Magnetic stirrer 10 Sampling container 12 Additive concentration analyzer 14 Operation control device 15 Display device 16 Supply tank 17 External computer

Continuation of front page (56) References JP-A-61-73884 (JP, A) JP-A-1-268878 (JP, A) JP-A-62-147304 (JP, A) JP-A-59-20462 (JP, A) JP-A-59-80768 (JP, A) JP-A-4-276081 (JP, A) JP-A-6-265510 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) C23C 18/00-18/54 G01N 1/10 G01N 33/20

Claims (3)

(57) [Claims] 1. A solder plating solution analyzing circulation tank was returned to the plating solution tank solder it is taken out of the solder plating solution continuously from the solder plating bath in the solder plating step, Sn ²⁺ in the solder plating solution, One analysis container capable of analyzing the concentration of free acid and Pb ²⁺ , an electrode provided in the analysis container, and an additive concentration analysis unit capable of analyzing the additive concentration; A sampling mechanism that samples the solder plating solution from the solder plating solution analysis circulation tank into the analysis container, a reagent supply unit that supplies various reagents necessary for the concentration analysis to the analysis container, and performs the concentration analysis. The analyzing container during the step of performing,
A cleaning liquid supply unit for cleaning the electrode and the additive concentration analysis unit,
An arithmetic and control unit that controls each of the device units and calculates a replenishment amount of each component from a result obtained by the concentration analysis,
A display device for displaying the analysis result and the replenishment amount; and a solder plating solution automatic management device. 2. The automatic solder plating solution management apparatus according to claim 1, wherein the arithmetic and control unit further has a function of transmitting the analysis result, the replenishment amount and the integrated replenishment amount to an external computer. 3. The solder plating solution automatic management device according to claim 1, wherein the arithmetic and control unit controls a replenishing pump installed in a replenishing tank based on the calculated replenishing amount.