KR200276797Y1 - material concentration sensing apparatus and confirming apparatus using thereof - Google Patents

Abstract

The present invention enables precise measurement and confirmation of the concentration of certain substances in chemicals in an electronic way to ensure uniform product performance, reduce the time required for processing and the amount of chemicals used in the work. The present invention relates to a specific material concentration detection device and a specific material concentration checking device using the same.

In a specific material concentration detection apparatus according to an aspect of the present invention, the entire surface of a metal plate serving as an electrode plate is insulated, and a portion of the insulation coating is removed to form a peeling part, and the metal plate exposed through the peeling part. Insulating electrode plates configured to allow leakage current to flow through are made to face each other at a predetermined interval, thereby detecting the concentration of a specific substance in the liquid chemical by resistance or capacitance between the insulating electrode plates.

Description

Specific substance concentration detecting apparatus and specific substance concentration checking apparatus using the same

The present invention relates to a specific substance concentration detecting apparatus and a specific substance concentration detecting apparatus using the same, and in particular, a specific substance concentration detecting apparatus for precisely detecting and confirming the concentration of a specific substance contained in a liquid chemical in an electronic manner, and It relates to a specific substance concentration checking device using the same.

In general, in manufacturing a printed circuit board, sulfuric acid fruit water (H ₂₎ containing an organic substance which is frequently changed in dissolution state in order to remove unnecessary parts of a specific material included in the printed circuit board, for example, copper (Cu). SO ₄ + H ₂ O ₂ + organics). That is, etching is performed while the printed circuit board is precipitated in the treatment tank filled with sulfuric acid fruit water.

On the other hand, when the dissolved copper concentration reaches a saturation state, since no further etching is performed, the sulfuric acid fruit water, which is an etching solution, needs to be replaced or supplemented. Should be checked. To this end, conventionally, the operator has measured the copper concentration on the neck side using a cork ball hydrometer using the principle of buoyancy. The process is not only annoying work requiring the worker's attention, but also the measurement results are different depending on the skill of the operator. There is a problem that the uniformity of the quality of the circuit board is not guaranteed. In addition, during this process, the operator does not quickly grasp the saturation of the copper concentration, which increases the time required for etching, and conversely, the chemical is wasted by replenishing or replacing the sulfuric acid fruit water even though the saturation is not reached. There is this.

The present invention enables precise measurement and confirmation of the concentration of certain substances in chemicals in an electronic way to ensure uniform product performance, reduce the time required for processing and the amount of chemicals used in the work. It is an object of the present invention to provide a specific material concentration detection device and a specific material concentration checking device using the same.

Specific material concentration detection apparatus according to an aspect of the present invention for achieving the above object is an insulating coating of the entire surface of the metal plate functioning as an electrode plate, a portion of the insulating coating is removed to form a peeling, the foil Insulating electrode plates configured to allow leakage current to flow through the metal plate exposed through the skin are faced at predetermined intervals to detect the concentration of a specific substance in the liquid chemical by resistance or capacitance between the insulating electrode plates. Done.

According to another aspect of the present invention, a specific material concentration checking apparatus is coated with an entire surface of a metal plate functioning as an electrode plate, and a part of the insulating coating is removed to form a peeling part, and the metal plate exposed through the peeling part. An electrical quantity sensor configured to face the insulating electrode plates configured to flow through the leakage current at predetermined intervals; A bridge circuit configured to include the electrical quantity sensor as an impedance of one branch, and the other branches include at least one fixed electric element and a variable electric element; Variable adjuster means for adjusting a value of the variable electric element; Current detection means for detecting a current flowing in the balance detection stage of the bridge circuit; Controlling the driving of the variable adjusting means, substituting the current detection value provided from the current detecting means into a predetermined calculation formula to calculate the resistance or capacitance of the electrical quantity sensor, and corresponding to the calculated resistance or capacitance And control means for outputting the concentration of the specific substance and display means for displaying the concentration of the specific substance outputted from the control means.

1 is a view for explaining the capacitance of a general flat plate capacitor,

Figure 2a is a block diagram of a specific material concentration detection device according to a preferred embodiment of the present invention, Figure 2b is a cross-sectional view taken along the line A-A,

3 is a configuration diagram in which the capacitance of the specific substance concentration detection device shown in FIG. 2 is equivalently converted into a flat plate capacitor;

4 is a diagram for explaining a general bridge circuit;

5 is a circuit diagram according to an embodiment of a bridge circuit configured by equivalently converting a specific substance concentration detection device of the present invention;

6 is a schematic appearance configuration diagram of a specific substance concentration checking apparatus of the present invention,

7 is an electrical block diagram of a specific substance concentration checking apparatus of the present invention,

8 is a flowchart for explaining the operation of the specific substance concentration checking apparatus of the present invention,

9 is a flowchart illustrating a process of checking the saturation state of a specific material of the present invention.

*** Explanation of symbols for the main parts of the drawing ***

10: computer body, 12: data storage unit,

14: program storage, 16: A / D converter,

18: central control unit, 20: display unit,

30: drive circuit portion, 32: current detection portion,

34: variable adjuster, 36: regulating motor,

38: solenoid valve drive unit, 40: solenoid valve,

50: chemical treatment tank, 60: electrical quantity sensor,

62: metal plate, 64: insulation coating,

66: thin skin portion, 67: electrode lead wire,

68: holder, 70: storage tank

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a view for explaining the capacitance of a general flat plate capacitor. As shown in FIG. 1, when a dielectric is placed between two parallel electrode plates, the electric field is agglomerated by the dielectric constant of the dielectric, and more electric fields are accumulated between the two electrode plates. In other words, an increase in the accumulation capacity of the electric field increases the capacitance between the two electrode plates.

On the other hand, since each dielectric has a different dielectric constant, the capacitance of the capacitor also changes depending on the type of dielectric placed between the two electrode plates. Thus, the relative dielectric constants of pure chemicals, for example pure sulfuric acid fruit water, and those of other substances, such as copper, are naturally different. Therefore, if the relative dielectric constant of a pure chemical is measured and the relative dielectric constant of other substances contained therein is measured and plotted in advance, the concentration of a specific substance dissolved in the liquid chemical can be measured. Will be.

Returning to FIG. 1, in the case of an infinite plate capacitor filled with a relative dielectric constant epsilon ( ₀ ) and having an area A and an electrode plate spacing d, the capacitance C becomes as shown in Equation 1 below.

= [F]

In equation 1, epsilon sub 0 represents the permittivity of air.

Figure 2a is a block diagram of a specific material concentration detection apparatus according to a preferred embodiment of the present invention, Figure 2b is a cross-sectional view taken along the line A-A in Figure 2a. As shown in FIG. 2, the specific material concentration detection device (hereinafter, referred to as “electric amount sensor” 60) used in the present invention has a predetermined interval between the electrode plates 62 coated with an insulating material on its entire surface. A portion of the insulating coating 62 is removed (hereinafter, referred to as "thin skin" 66) so that a predetermined leakage current flows through the electrode plate 62. The electrode plate can be exposed to the outside (hereinafter, such an electrode plate is referred to as an "insulating electrode plate"). As described above, in the electrical quantity sensor 60 of the present invention, the leakage current through the electrode plate 62 can flow by the formation of the skin portion 66 so that the resistance thereof is dissolved in the liquid chemical by measuring the resistance thereof. It is possible to measure the concentration of certain substances, in particular metallic substances. The electrical sensor 60 may be implemented in a flat shape, in which two flat insulating electrode plates face each other at predetermined intervals.

However, in the case of the flat plate type, the capacitance variation of the capacitance sensor according to the change of the concentration of a specific substance is small, thereby ensuring a smooth flow of the chemical and increasing the surface area, for example, as shown in FIG. It is comprised so that the insulated electrode plates which are formed in the shape of a recess may overlap each other.

In the drawing, reference numeral 67 denotes an electrode lead line for connecting the electrical quantity sensor 60 to an external circuit, for example, a bridge circuit as described below, and 68 denotes that two insulating electrode plates can always maintain the same phase with each other. The stator holding the two electrode leader lines 67 stably is shown. Of course, the electrode lead wire 67 should also be insulated.

FIG. 3 is a diagram in which the capacitance of the electricity amount sensor illustrated in FIG. 2 is equivalently converted into a flat plate capacitor. The distance sensor of the present invention having the above-described configuration has a half distance between the same volume capacitors. As a result, the surface area effect is increased and the capacitance is increased by about six times. As a result, the measurement range is widened, so that the change in concentration of a specific substance can be detected more accurately.

On the other hand, when copper (Cu) is dissolved in sulfuric acid, a chemical, the conductivity and dielectric constant of the chemical are changed, and the change in conductivity can be known by measuring the resistance applied to the electric field sensor 60. The change can be known by measuring the capacitance, so that when the bridge circuit is used, both can be measured simultaneously.

4 is a diagram for explaining a general bridge circuit. As shown in FIG. 4, the general bridge circuit is composed of four impedance branches, each of which has impedance magnitudes of Z1, Z2, Z3, and Z4, and the current flowing through each impedance is represented by I1, I2, I3 and If I4, the voltage allocated to each impedance is the product of each impedance and current as shown in Equation 2 below.

Z1, V2 = I2 Z2, V3 = I3 Z3, V4 = I4 Z4

On the other hand, if the bridge circuit is balanced and the current flowing in the galvanometer becomes 0, the voltage and current of each branch maintain the relationship of Equations 3 to 5 below.

V1 = V2, V3 = V4, I1 = I3, I2 = I4,

Z1 = I2 Z2

Z3 = I2 Z4

Then, equation (6) is derived from equations (4) and (5).

Z2 = Z1 Z4

5 is a circuit diagram of an embodiment of a bridge circuit configured by equivalently converting a specific substance concentration detection device of the present invention. As shown in FIG. 5, the electrical quantity sensor 60 of the present invention can be equivalently converted into a configuration in which the resistor R4 and the capacitor C4 are connected in parallel, in which case the overall impedance Z4 is below. Equation 6 is as follows.

On the other hand, reference numerals R1, R2 and R3 denote variable resistors, and C3 denotes fixed capacitors connected in parallel with the variable resistor R3. Reference numeral AC denotes an externally applied voltage source, for example, a sinusoidal AC voltage source. In this case, the impedance of each branch of the bridge circuit is expressed by Equations 8 to 10 below.

Z1 = R1

Z2 = R2

Here, assuming that no current flows in the galvanometer D, that is, assuming that the bridge circuit is in an equilibrium state, the relations of the following expressions 12 to 14 are established between the impedances.

Z3 * Z2 = Z1 * Z4

As a result, by substituting the values of the variable resistors R1, R2, R3 and the fixed capacitor C3 when the bridge circuit is balanced into equations (13) and (14), The resistance R4 and the capacitance C4 of the electric quantity sensor 60 according to the concentration can be obtained, and the resistance R4 and the capacitance C4 thus obtained are known to a resistance or capacitance to concentration conversion table. By assigning, the concentration of a specific substance can be confirmed.

Table 1 below is a table showing an experimental example of the resistance and capacitance to concentration conversion table in the process of etching the printed circuit board using the electrical sensor (60) of the present invention.

Cu content characteristics 15% Cu 16% Cu 17% Cu Saturation Resistance (R4) 340 Ω 328 Ω 320 Ω 309 Ω Capacitance (C4) 39.3 uF 43.8 uF 46.1 uF 49 uF

6 is a schematic appearance configuration diagram of a specific substance concentration checking apparatus of the present invention. As shown in Figure 6, the specific substance concentration confirmation device of the present invention, for example, is filled with sulfuric acid fruit water with a chemical to store the treatment tank 50, the chemical is carried out the etching process for the printed circuit board and The storage tank 70 to supply to the treatment tank 50, the solenoid valve 40 to control the supply of chemicals from the storage tank 70, the electrical quantity sensor 60 contained in the treatment tank 50, Receives data from the driving circuit unit 30 and the driving circuit unit 30 including a bridge circuit configured with the electrical quantity sensor 60 and a circuit for driving the solenoid valve 40, etc. The monitor 20 for checking the concentration of and visually confirming the computer main body 10 for controlling the opening and closing of the solenoid valve 40 and the processing result of the computer main body 10 via the driving circuit unit 30. It may be made, including.

7 is an electrical block diagram of a specific substance concentration checking apparatus of the present invention. As shown in FIG. 7, the display unit 20 may be implemented as a monitor, and the program storage unit 14 equipped with a specific substance concentration checking program of the present invention, the resistance R4 of the electrical quantity sensor 60. Alternatively, the data storage unit 12 in which the concentration conversion table of the specific substance corresponding to the value of the condenser C4, the necessary calculation formula, etc. are stored, and the analog current value measured by the current detection unit 32 described later is converted into digital data. The A / D conversion unit 16 and the central control unit 10 that controls the overall operation of the device may be implemented by the computer main body 20 of FIG. 6.

On the other hand, the driving circuit unit 30 of FIG. 6 includes a current detector 32 for detecting a current flowing through the galvanometer D of the bridge circuit and the bridge circuit illustrated in FIG. 5 as a voltage, a variable resistor R2 of the bridge circuit, (( And a solenoid valve driver 38 for driving the solenoid valve 40, and a regulating motor 36 for adjusting R3). The regulating motor 36 may be embodied, for example, as a stepping motor capable of fine tuning.

8 is a flowchart for explaining the operation of the specific substance concentration checking apparatus of the present invention, it is revealed that the central control unit is performed as a subject unless otherwise described, and as described above, the dissolution concentration of copper for the printed circuit board Proceed to the description as to perform the operation to check.

As shown in FIG. 8, first, in step S10, the control motor 36 is controlled in a state where the variable resistor R1 is fixed to a predetermined value to adjust the variable resistors R2 and R3 to an initial state. In the case of adopting the bridge circuit of FIG. 5, the initial values of the variable resistors R2 and R3 are adjustable maximum values, while the initial values of the variable resistors R3 become zero.

Next, with the progress of the etching operation, the concentration of copper dissolved in sulfuric acid fruit water is detected. To this end, in step S12 to step S15, the variable resistor R2 is continuously changed by a predetermined increment ΔRa while the current detector 32 is used. The current value detected by) is checked to determine whether the current I flowing through the galvanometer D of the bridge circuit has reached a resonance state. In this way, when it is confirmed in step S15 that the current I flowing in the galvanometer D reaches the resonance point, in step S16 the current variable resistor R2 value is stored, and in step S18, the variable resistor R2 value is stored. The capacitance C4 of the electrical quantity sensor 60 is calculated by substituting a predetermined formula, that is, equation (13).

Next, in steps S20 to S24, the current is detected by the current detector 32 while checking the current value detected by the current detector 32 while continuously changing the variable resistor R3 by a predetermined increment ΔRb. It is determined whether (I) is zero, that is, the bridge circuit has reached an equilibrium state. In this way, when it is confirmed in step S24 that the bridge circuit has reached an equilibrium state, in step S26 the current variable resistor R3 value is stored, and in step S28, the variable resistor R3 value is again determined by a predetermined calculation formula, that is, a mathematical expression. Substituting into Equation 14, the value of the resistance R4 of the electrical quantity sensor 60 is calculated.

Next, in step S30, the capacitance C4 or the resistor R4 is substituted into the above-described conversion table to confirm the copper concentration, and in step S32, necessary control, for example, an indication or alarm or solenoid valve 40 of the confirmed concentration, is checked. Control such as opening).

Here, only one of the resistance R4 and the capacitance C4 of the electrical quantity sensor 60 may be adopted depending on whether the specific material is a metal material or an organic compound, in this case the configuration of the bridge circuit. And the configuration of the driving circuit according to this will be different. For example, when only the capacitance of the electrical quantity sensor 60 is used, the resistor R3 may be replaced by a fixed resistor in the bridge circuit, and in this case, only one regulating motor 36 may be provided.

Furthermore, the bridge circuit of FIG. 5 may be modified by varying the capacitor C3 instead of the resistor R3.

9 is a flowchart illustrating a process of checking the saturation state of a specific material of the present invention. As shown in FIG. 9, in step S50, the resistance R4 and the capacitance C4 of the electrical quantity sensor 60 are detected by the process shown in FIG. 7, and in step S52, the resistance R4 thus detected is detected. ) And whether the capacitance C4 has reached a predetermined predetermined range.

As a result of the determination in step S52, it is determined whether the resistance R4 and the capacitance C4 have reached within a predetermined range. As a result of the determination in step S52, when the resistance R4 and the capacitance C4 do not reach within a predetermined predetermined range, the process returns to step S50, and when it reaches the step S53, the current I is measured. Done. In step S54, it is determined whether the current rate of change I / Δt per predetermined time is equal to or less than a predetermined value. As a result of the determination in step S54, when the current change rate per predetermined time is larger than the predetermined value, it means that the melting is still in progress, and the flow returns to step S53. On the other hand, when the determination result in step S54 is that the current change rate per predetermined time (I / Δt) is less than or equal to the predetermined value, it is determined that the state is saturated and the necessary control is performed by performing step S56, for example, control or replacement of chemicals. Will be performed.

The device for detecting a specific material concentration of the present invention and the device for checking a specific material concentration using the same may be used in the etching field of the printed circuit board or the general plating field as described above. In addition, the concentration of the specific material in the liquid chemical may be widely used. It can be used to measure.

The specific substance concentration detecting apparatus of the present invention and the specific substance concentration detecting apparatus using the same are not limited to the above-described embodiments and may be variously modified within the range allowed by the technical idea of the present invention. For example, it may be possible to increase the number of layers of the insulated electrode plate than shown in FIG. 3. In addition, the size, number, formation positions, and the like of the skin portion formed on the insulating electrode plate may be appropriately modified.

According to the present invention as described above, it is possible to precisely measure and confirm the concentration of a specific substance contained in the chemical in an electrical manner to ensure uniform product performance, reduce the time required for processing work There is an effect to reduce the amount of chemicals used in.

Claims (6)

The entire surface of the metal plate functioning as an electrode plate is insulated, and a part of the insulating coating is removed to form a peeling part, and an insulating electrode plate configured to allow a leakage current to flow through the metal plate exposed through the peeling part is previously prepared. Are face to face at regular intervals, Specific material concentration detection device for detecting the concentration of the specific material in the liquid chemical by the resistance or capacitance between the insulating electrode plate. The method of claim 1, And the insulating electrode plate is made of at least one layer. The apparatus of claim 1 or 2, wherein the specific substance comprises a metal substance. The apparatus for detecting a specific substance concentration according to claim 1 or 2, wherein the specific substance comprises an organic compound. The entire surface of the metal plate functioning as an electrode plate is insulated, and a part of the insulating coating is removed to form a peeling part, and an insulating electrode plate configured to allow a leakage current to flow through the metal plate exposed through the peeling part is previously prepared. Electrical quantity sensors which face each other at a predetermined interval; A bridge circuit configured to include the electrical quantity sensor as an impedance of one branch, and the other branches include at least one fixed electric element and a variable electric element; Variable adjuster means for adjusting a value of the variable electric element; Current detection means for detecting a current flowing in the balance detection stage of the bridge circuit; Controlling the driving of the variable adjusting means, substituting the current detection value provided from the current detecting means into a predetermined calculation formula to calculate the resistance or capacitance of the electrical quantity sensor, and corresponding to the calculated resistance or capacitance Control means for outputting a concentration of a specific substance and And a display means for displaying the concentration of the specific substance outputted from the control means. The apparatus of claim 5, wherein the variable electric element and the fixed electric element comprise a resistor or a capacitor.