JP4759834B2 - Electroplating equipment for film carriers - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electroplating apparatus for a film carrier for performing electroplating on a film carrier having blind vias.
[0002]
[Prior art]
An example of an electroplating apparatus that performs electroplating while vertically conveying a conventional web-like film carrier is shown in FIG. The conventional electroplating apparatus has a vertical conveyance structure in which a web-like film carrier 121 is vertically conveyed by a conveyance roll 131, and a plating solution jet 143 and a cylindrical anode electrode are provided inside the plating tank 110. 131 is provided, and the plating solution is jetted from the chemical solution layer 140 directly to the plating tank 110 from the jet port 143 via the delivery pipe 142 by the circulation pump 141. On the other hand, the plating surface of the film carrier 121 is electrically connected to the conductive transport roll 131, and a voltage is applied between the cylindrical anode electrode 132 and the cathode electrode formed of the transport roll 131 by the plating power source 150. Then, electrolytic plating is performed on the surface to be plated of the film carrier 121. In addition, a heater, a temperature controller, and a temperature measuring resistor are incorporated in the chemical bath 140, and the plating solution is maintained at a predetermined temperature. Further, a filter and a flow meter are attached in the delivery pipe 141 between the pump 141 and the jet port 143 to control the flow rate of the plating solution jetted from the jet port 143 while the plating solution is filtered. .
[0003]
As described above, this type of jet electroplating apparatus causes the plating solution to be jetted from the jet port 143 of the plating tank 110 by the pump 141. However, depending on the shape and installation interval of the jet port 143, the inside of the plating tank 110 may be used. The flow velocity in the vicinity of the jet port 143 is fast and the plating solution flows toward the film carrier 121. However, the flow direction of the plating solution on the surface of the film carrier 121 varies, and the plating solution stagnates inside the plating tank 110, and turbulent flow occurs. appear.
[0004]
For this reason, a variation in the amount of the plating solution impinging on the surface to be plated of the film carrier 121 occurs, the amount of metal ions carried by electrolysis varies, and the amount of precipitation varies, so that the plating film thickness is within the surface to be plated of the film carrier. The problem is that it varies widely.
[0005]
In addition, due to the influence of turbulent flow, it is difficult for the plating solution to be exchanged in the blind vias laid out on the surface to be plated of the film carrier 121, and the plating deposition amount at the bottom of the via is reduced and the throwing power tends to deteriorate. is there.
As a countermeasure against this problem, as shown in FIG. 5, a plurality of detachable shielding plates 161 are provided above and below the conveying portion of the film carrier 121 in the plating tank 110 to control the amount of plating deposition by electrolysis. Thus, there has been proposed a jet plating apparatus for reducing the plating thickness variation between the center portion and the edge portion of the film carrier 121 and improving the uniformity of the plating film thickness.
[0006]
Also, jet plating for the purpose of increasing the throwing power by increasing the discharge amount of the plating solution from the jet port 143, facilitating the exchange of the plating solution in the blind via, and increasing the plating deposition amount at the bottom of the via. A device has been proposed.
[0007]
[Problems to be solved by the invention]
As described above, the problems with the conventional plating apparatus are that the flow velocity in the vicinity of the jet port 143 is fast inside the plating tank 110, the amount of the plating solution impinging on the surface to be plated of the film carrier 121 varies widely, The amount of the metal ions carried by the carrier fluctuates and the amount of precipitation varies, so that the plating film thickness tends to vary greatly in the film carrier plane.
[0008]
Further, in the plating apparatus provided with the shielding plate 161 as shown in FIG. 5, the flow of the plating solution is made uniform so that the optimum plating film thickness distribution is obtained with respect to the change in the size of the film carrier 121. It takes a lot of time to optimize the shape and size of the plate 161. The reason is that it is very difficult to install the shielding plate 161 between the jet port 143 and the film carrier 121, the installation method becomes complicated, and it takes time and effort to replace it. Even if a plating jig provided with the shielding plate 161 can be manufactured, several sets must be prepared so that a plating film thickness suitable for various film carrier sizes can be obtained. Problems arise in the management of
[0009]
Further, in the conventional plating apparatus, when the diameter of the blind via becomes a small diameter of 100 μm or less, the plating solution stagnates inside the plating tank 110 and turbulence occurs. Due to the influence, it is difficult for the plating solution to be exchanged in the blind via laid out on the plating surface of the film carrier 121, and the plating deposition amount at the bottom of the via is reduced and the throwing power tends to be deteriorated. By moving the film carrier 121 in the conveying direction, it is possible to prevent variation in the flow distribution of the plating solution, but the plating solution that has not overflowed is stagnated inside the plating tank 110, and turbulent flow occurs. It has the problem that it cannot be expected to be as effective as the content.
[0010]
The present invention has been devised in view of the above problems. When electroplating is performed on a film carrier having a blind via, the plating film thickness distribution on the plated surface is made uniform, and the plating throwing power ( It is an object of the present invention to provide an electroplating apparatus for a film carrier that can improve the uniformity of electrodeposition.
[0011]
In order to solve the above-mentioned problems in the present invention, first, in claim 1, an electroplating apparatus for performing electroplating while horizontally conveying a web-like film carrier, comprising at least an outer plating tank and an overflow portion An inner plating tank having a plurality of discharge ports, an anode electrode having a grid-like electrode, a chemical tank, and a power source for plating, and provided at the bottom of the inner plating tank the plating solution as a laminar flow in the jet tank, from said plurality of discharge port of the jet tank, toward the film carrier is horizontally conveyed, the by jet electroplated through the anode electrode having a grid-shaped electrode with the plating solution The electroplating apparatus for a film carrier is characterized by being performed.
[0012]
Further, in claim 2, the jet tank has a box-shaped structure, and an upper surface thereof is formed as a discharge plate having the plurality of discharge ports, and a plurality of dispersion ports are provided between the bottom of the jet tank and the discharge plate. The electroplating apparatus for a film carrier according to claim 1, wherein the electroplating apparatus has a dispersion plate having
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic sectional view showing an embodiment of an electroplating apparatus for a film carrier of the present invention.
The electroplating apparatus for a film carrier of the present invention is an electroplating apparatus that performs electroplating while horizontally conveying a web-like film carrier, and has a jet tank 30 having a jet structure having a discharge port 33 at the bottom of the inner plating tank 20. Then, electroplating is performed in a state where the plating solution is jetted to the plating surface of the film carrier 71 through the anode electrode 40 and rectified into a laminar flow of the plating solution. For this reason, plating can be performed while controlling the flow rate of these plating solutions, and a uniform plating film thickness can be obtained. Moreover, the plating swing power in the blind via laid out on the plating surface can be improved. Here, the rectification of the plating solution means that the flow of the plating solution is adjusted and the flow is free from disturbance.
[0014]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the electroplating apparatus 100 for a film carrier of the present invention includes an outer plating tank 10, an inner plating tank 20 having an overflow portion, a jet tank 30 having a discharge port 33, and a grid electrode 42. The anode electrode 40 has a cathode electrode composed of a transport roll 72, a chemical bath 50, a plating power source 60, and a transport roll 72 for transporting the film carrier 71.
[0015]
The plating tank has a two-layer structure of an outer plating tank 10 and an inner plating tank 20, and a jet tank 30 having a discharge port 33 is provided at the bottom of the inner plating tank 20. A laminar flow of the plating solution is formed by spraying from 33 toward the plating surface of the film carrier 71. A voltage is applied between the anode electrode 40 having the grid electrode 41 and the cathode electrode formed of the transport roll 72 from the power source 60 for plating, and the plating surface of the film carrier 71 is subjected to electrolytic plating.
The plating solution is a copper sulfate plating solution containing copper sulfate pentahydrate as a main component, and the plating solution temperature is set to a temperature range of 20 to 30 ° C. to perform plating.
The outer plating tank 10 and the inner plating tank 20 are formed of a plastic material, and the material is eroded by copper sulfate pentahydrate which is a main component of a plating solution such as polypropylene (PP) or vinyl chloride (PVC). A plastic material that can be used at 30 ° C. is desirable.
[0016]
The jet tank 30 has a box-like structure, a discharge plate 31 having a discharge port 33 on the upper surface, and a dispersion plate 32 having a dispersion port 34 in the middle. The dispersion plate 32 and the dispersion port 34 are This is provided to uniformly jet the plating solution when the plating solution is jetted from the discharge port 33. Further, the jet tank 30 is connected to the chemical tank 50 via a liquid feed pipe 11 having a flow meter 83, a filter 82 and a pump 81.
As a preferable example of the discharge port 33 and the dispersion port 34 of the jet tank 30, a discharge plate 31 and a dispersion plate 32 having circular discharge ports 33 and dispersion ports 34 of 2 mmφ formed at intervals of 10 mm can be mentioned.
The jet tank 30 is provided in a planar shape, but is preferably divided into at least three or more.
[0017]
An anode electrode 40 having a grid-like electrode 41 is provided between the discharge port 33 of the jet tank 30 and the film carrier 71, and between the anode electrode 40 and the conductive transport roll 72 having conductivity from the plating power source 60. In a state where a voltage is applied, the plating solution is jetted from the discharge port 31 of the jet tank 30 through the grid-like anode electrode to form a uniform laminar flow of the plating solution.
An overflow portion 21 is provided on a side surface of the inner plating tank 20 at a position higher than the film carrier 71, and the overflow portion 21 is formed as, for example, a plurality of elliptical opening edges.
Since the overflow part 21 of the inner plating tank 20 has a plurality of elliptical opening edges, the flow rate of the plating solution flowing inside the inner plating tank 20 is dispersed and overflows as a laminar flow.
[0018]
The chemical bath 50 has a built-in heater, temperature controller, and resistance thermometer. The plating solution adjusted to a temperature of 20 to 30 ° C. is inverter controlled (the frequency of the input voltage of the pump according to the set flow rate) Is supplied to the jet tank 30 via the filter 82 and the flow meter 83.
The flow meter 83 monitors the jet flow rate of the plating solution and outputs a control signal to the inverter circuit of the circulation pump 81 to control the jet flow rate. The jet flow rate is desirably 30 L / min or more. The cartridge-type filter 82 installed in the liquid feed pipe 11 is precisely filtered using a filter having a hole diameter of about 1.0 μm so that dust in the plating solution does not adhere to the plating film of the film. It is configured to
[0019]
The plating solution supplied to the jet tank 30 is made uniform by a dispersion plate 32 having a dispersion port 34 provided in the middle of the jet tank 30, and jetted into the inner plating tank 20 from the discharge port 33 of the discharge plate 31. Then, a laminar flow of the plating solution is formed on the plating surface of the film carrier 71 through the grid-like anode electrode. Since the area of the plating solution jetted from the discharge port 33 of the jet tank 30 is reduced by the discharge port 33, the plating solution flows toward the plating surface of the film carrier 71 at a high flow rate, but from the overflow portion 21 of the inner plating tank 20. Since the overflow is restricted, the occurrence of turbulent flow in the inner plating tank 20 can be prevented. Therefore, plating is performed while controlling the flow rate of the plating solution toward the plating surface of the film carrier 71, the plating film thickness in the film surface can be made uniform, and the plating throwing power in the blind via laid out on the plating surface is improved. Can be improved.
[0020]
In a state where a laminar flow of the plating solution is formed on the plating surface of the film carrier 71, a voltage is generated between the anode electrode 40 having the grid-like electrode 41 and the cathode electrode made of the conductive transport roll 72 by the plating power source 60. Is applied to the plated surface of the film carrier 71 for electrolytic plating.
Since the transport roll 72 having conductivity is in contact with the plating surface of the film carrier 71, the actual cathode electrode becomes the plating surface of the film carrier 71.
[0021]
According to the present invention, by providing the jet tank 30 at the bottom of the inner plating tank 20, electrolytic plating is performed while controlling the flow rate of the plating solution while the plating solution is rectified into a laminar flow on the plating surface of the film carrier. Thus, a uniform plating film thickness can be obtained. Specifically, it can be suppressed to ± 10% or less with variation 3σ / x. Moreover, the plating throwing power in the blind via laid out on the plating surface can be improved by 10% or more.
[0022]
Furthermore, it is easy to determine the conditions for obtaining the optimum flow velocity distribution. This makes it possible to immediately respond to changes in conditions such as changes in the size of the film carrier.
The reason is that an optimum flow velocity distribution can be obtained, and conditions can be determined only by controlling the jet flow rate of the pump.
[0023]
In the jet tank 30 described in the above embodiment, the number of jet tanks can be increased from three to plural, and plating for applying a voltage between the anode electrode 40 and the cathode electrode is possible. The power source 60 can use not only direct current but also a constant current pulse and a reverse current pulse of a pulse current.
[0024]
【The invention's effect】
By using the electroplating apparatus for a film carrier of the present invention, the plating film thickness in the film carrier surface can be made uniform, and the improvement of the plating throwing power in the blind via laid out on the plating surface can be improved. A reliable film carrier can be obtained.
In addition, it is easy to find the conditions for obtaining the optimum flow velocity distribution. This makes it possible to change the conditions, such as changing the film size, by simply controlling the flow rate of the pump and respond immediately. be able to.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing an embodiment of an electroplating apparatus for a film carrier of the present invention.
FIG. 2 is a schematic plan view showing an example of a jet tank.
FIG. 3 is a schematic plan view showing an example of an anode electrode.
FIG. 4 is a schematic configuration diagram showing an example of a general electroplating apparatus using jet plating.
FIG. 5 is an explanatory diagram showing an example of a configuration of a shielding plate.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Outer plating tank 11 ... Liquid feed pipe 12 ... Recovery pipe 20 ... Inner plating tank 30 ... Jet tank 31 ... Discharge plate 32 ... Dispersion plate 33 ... Discharge port 34 ... Dispersion port 40 ... ... Anode electrode 41 ... Grid electrode 42 ... Electrode frame 50 ... Chemical solution tank 60 ... Plating power source 71 ... Film carrier 72 ... Conveying roll 81 ... Pump 82 ... Filtration filter 83 ... Flow meter 100 …… Electroplating device for film carrier 110 …… Plating tank 121 …… Film carrier 131 …… Conveying roll 132 …… Anode electrode 140 …… Chemical solution tank 141 …… Sending pipe 143 …… Jet port 150 …… Plating power source 161 ……Shield

Claims (2)

An electroplating apparatus for performing electroplating while horizontally transporting a web-like film carrier, comprising at least an outer plating tank, an inner plating tank having an overflow portion, a jet tank having a plurality of discharge ports, and a lattice-shaped An anode electrode having an electrode, a chemical solution tank, and a power source for plating, and a plating solution is made into a laminar flow in the jet tank provided at the bottom of the inner plating tank, from the plurality of discharge ports of the jet tank An electroplating apparatus for a film carrier, wherein electroplating is performed by jetting the plating solution through an anode electrode having a grid-like electrode toward a horizontally conveyed film carrier. The jet tank has a box-shaped structure, and an upper surface thereof is formed as a discharge plate having the plurality of discharge ports, and includes a dispersion plate having a plurality of dispersion ports between the bottom of the jet tank and the discharge plate. 2. The electroplating apparatus for a film carrier according to claim 1, wherein the electroplating apparatus is a film carrier.

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