TWI477659B - Conductive anode structure in water - Google Patents

Description

Conductive anode structure in water

The invention relates to a conductive anode structure in water, in particular to serially connect an external power source and a main plating unit to prevent the copper sulfate crystal of the plating solution from affecting the plating operation.

Metallic copper has excellent electrical conduction characteristics and is well sourced, and therefore, it is widely used in electrical wiring of electric wires or circuit boards for electrical conduction. Since the influence of copper purity on electrical conductivity is very important, how to manufacture high-purity copper or copper foil has always been the main goal of the industry. Among them, the electroplating copper process is one of the most important processes and can be directly formed on the substrate. A copper foil having a uniform thickness and a flat surface is formed on the copper layer of the printed circuit board or on the roller.

In the conventional technology, the commonly used electroplating copper process mainly uses a plating solution containing copper sulfate, a brightener, a chelating agent, a buffering agent and other additives, and is reduced to high-purity metallic copper by external electric power to be precipitated on the cathode, and is contained. An anode composed of a material having a low copper content or a low copper purity is oxidized to copper ions by an oxidation reaction to dissolve in the plating solution, and impurities are released therefrom to provide a copper source. The anode is directly dissolved in the plating solution, generally referred to as a soluble anode, and may include phosphorous copper blocks contained in a titanium basket and disposed in pairs on the cathode side. However, during the electroplating process, the volume of the phosphorous copper block is gradually reduced, and the dissociation speed of the surface is different, often causing copper chips to collapse, so it is necessary to periodically stop the electroplating operation to replace the phosphorous copper block and remove the collapsed copper scrap. Causes inconvenience in production and affects production. In addition, for products with specific properties, the purity requirements are higher, such as 99.9% or more, or even as high as 99.99%. Moreover, the speed is fast, the thickness is thin, and the uniformity is good. In the case of higher current density, the soluble anode is prone to polarization, and during the electroplating process, a poor current distribution is likely to occur due to the shape change of the anode. Therefore, generally, an insoluble anode can be used, that is, a material having a higher stability, such as a tantalum anode, a platinum titanium anode, a titanium-coated copper anode, which can be formed into a flat plate shape and arranged parallel to the cathode, and the copper source is composed of Additional additives to the copper-containing compound are provided by dissolving in a copper sulfate bath, such as copper oxide. In addition, the insoluble anode is often made into a mesh shape, which is favorable for the circulation of the plating solution, and particularly controls the electric field distribution between the anode and the cathode in the plating solution, thereby controlling the current density to produce an electroplated copper layer having a uniform thickness.

In addition, in order to improve the allowable current density of the plating and to lower the temperature of the plating solution to improve the plating quality, it is usually possible to perform stirring by means of air, mechanical, solution jet or moving plating. The gas injection machine injects air into bubbles, and the air is floated to agitate the plating solution, which is the most commonly used method. However, the above-mentioned conventional technology has the disadvantage that the lifting bubbles in the plating solution will carry out or eject a part of the plating solution, and then float to the outside of the plating tank and adhere to the surrounding components, devices or equipment, especially the sulfuric acid contained in the plating solution. Copper, which precipitates solid copper sulphate after attachment, affects the electrical properties of the component being attached, such as increasing resistance. Therefore, there is a need for a conductive anode structure in water that prevents the plating solution carried by the bubbles from precipitating copper sulfate, thereby solving the problems of the above conventional techniques.

The main object of the present invention is to provide a conductive anode structure in water, comprising a soaking liquid, at least one fixing component and at least one conductive container, which can be used for serially connecting an external power source and a main plating unit, and the main plating unit includes at least one insoluble anode. a cathode, a main plating tank, a plating solution and a stirring device, and a stirring device for stirring the plating solution, each insoluble anode has a hook-shaped front end and is hooked to the inner side of the conductive container, and the plating solution is accommodated in the main plating tank Inside, the soaking liquid may be pure water or tap water, and is contained in a conductive container, and part The fixing member and the insoluble anode are immersed in the infusion solution, and the insoluble anode is locked to the inner side of the conductive container by the fixing member, so that the conductive container and the insoluble anode are electrically connected to each other.

The fixing element and the conductive container are electrically conductive. The positive electrode of the external power source is electrically connected to the conductive container via an electrically conductive wire, and the electrically conductive wire is locked to the conductive container by the fixing member. The cathode of the main plating unit is connected to the negative pole of the external power source. Hydrogen ions and metal ions may be included, wherein the metal ions include at least one of copper ions, nickel ions, zinc ions, and chromium ions. Further, the plating solution 57 may further contain a brightener and an additive.

When the external power source supplies power, the current flows from the external power source through the conductive anode structure in the water to the insoluble anode of the main plating unit to oxidize water in the plating solution to generate oxygen, and the copper ions in the plating solution are reduced to metal copper. The electrolysis is provided on the cathode, and the current flows from the cathode to the external power source to form an electrically connected circuit, which provides a plating function.

10‧‧‧Water conductive anode structure

11‧‧‧Electrical container

13‧‧‧Fixed components

13a‧‧‧screws

13b‧‧‧Upper casing

13c‧‧‧ lower case

15‧‧‧ soaking solution

40‧‧‧External power supply

50‧‧‧Main plating unit

51‧‧‧Insoluble anode

53‧‧‧ cathode

55‧‧‧Main plating bath

57‧‧‧ plating solution

59‧‧‧Agitator

59a‧‧‧ gas injection machine

59b‧‧‧Injection tube

B‧‧‧ bubble

I‧‧‧current

The first figure shows a schematic view of the structure of the conductive anode in the water of the present invention.

The second figure shows a partial schematic view of the conductive anode structure of the present invention in combination with an insoluble anode.

The third figure shows a schematic view of the fixing elements in the electrically conductive anode structure of the invention.

The embodiments of the present invention will be described in more detail below with reference to the drawings and the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

Referring to the first figure, a schematic diagram of a conductive anode structure in the water of the present invention. As shown in the first figure, the underwater conductive anode structure 10 of the present invention mainly comprises a conductive container 11, a fixing element 13 and a soaking liquid 15 for serially connecting the external power source 40 and the main plating unit 50 to form an electrically connected circuit. Provides electroplating.

An external power source 40 is used to provide power.

The main plating unit 50 is used to realize the electroplating copper function, and the main plating unit 50 includes at least one insoluble anode 51, a cathode 53, a main plating tank 55, and a plating solution. 57 and a stirring device 59, wherein the plating solution 57 is accommodated in the main plating tank 55, and the insoluble anode 51 and the cathode 53 are immersed in the plating solution 57, and the stirring device 59 is used to stir the plating solution 57 to improve the main plating unit. The allowable current density of 50.

The insoluble anode 51 has a hook-shaped front end and may be a tantalum anode, a platinum titanium anode or a titanium-coated copper anode, or may be a titanium or titanium plated platinum, a titanium plated metal/corrosion resistant metal passivation layer, or a corrosion-resistant conductive non-metal. Composition, and the corrosion-resistant conductive non-metal system comprises graphite. The cathode 53 can be regarded as a plated member such as a substrate of a printed circuit board. The plating solution 57 may include hydrogen ions and metal ions, wherein the metal ions include at least one of copper ions, nickel ions, zinc ions, and chromium ions. Further, the plating solution 57 may further contain a brightener and an additive. The insoluble anode 51 and the cathode 53 are immersed in the plating solution 57. In order to obtain a more uniform current distribution to improve plating quality, the insoluble anodes 51 may be symmetrically disposed on both sides of the cathode 53, as shown in the drawing. However, the scope of the present invention is not limited thereto, and it is also within the scope of the present invention to configure the insoluble anode 51 in other manners.

Specifically, the agitating device 59 may include a gas injector 59a and a gas injection pipe 59b, wherein the gas injection device 59a is connected to the gas injection pipe 59b, and the gas injection pipe 59b is further pierced or piped in the main plating tank 55, so that the gas injection machine 59a Air is injected into the plating solution 57 via the gas injection pipe 59b to generate the bubble B, and the plating liquid 57 is stirred by the bubble B rising in the plating liquid 57 to cause disturbance.

The conductive container 11 and the fixing element 13 may be made of copper or a copper alloy. The soaking liquid 15 may be pure water or tap water, and is accommodated in the conductive container 11 to provide heat dissipation and cooling, and can effectively maintain electrical performance and prevent temperature. Excessively high adverse effects on plating quality. The fixing member 13 is disposed in the conductive container 10 for locking the insoluble anode 51 to the conductive container 11, and a portion of the fixing member 13 and a portion of the hook-shaped front end of the insoluble anode 51 are immersed in the soaking liquid 15.

In order to more clearly illustrate the technical features of the conductive anode structure in the water of the present invention, please refer to the second figure at the same time, the partial display of the conductive anode structure in water combined with the insoluble anode It is intended that only a portion of the conductive container 11 is displayed. As shown in the second figure, the conductive container 11 has a grooved strip shape or a U-shaped strip shape, and the hook-shaped front end of the insoluble anode 51 is hooked to the inner side of the conductive container 11, and the tail portion of the insoluble anode 51 It is immersed in the plating solution 57.

Further, the fixing member 13 may be attached to the insoluble anode 51 or attached to the conductive container 11.

Specifically, the fixing member 13 can be realized by an expansion screw as shown in the third figure, wherein the fixing member 13 includes a screw 13a, an upper sleeve body 13b and a lower sleeve body 13c, and the upper sleeve body 13b and the lower sleeve body 13c have individual The beveled surface of the upper sleeve 13b and the lower sleeve 13c are integrally formed by the beveled surface of the upper sleeve 13b and the lower sleeve 13c. Therefore, the upper surface of the upper sleeve 13b and the lower sleeve 13c can be locked by the screw 13 The body 13b and the lower casing 13ca cause the upper casing 13b and the lower casing 13c to be pressed against each other and exert a pressing force outward, and a pressing function can be provided to lock the insoluble anode 51 to the conductive container 11. However, the fixing member 13 of the present invention is not limited thereto, and it can also be realized by using other members having an outward pressing function.

The soaking liquid 15 itself is composed of water, so the heat capacity is quite large, and its main function is to provide heat dissipation and cooling, which can reduce the temperature of the conductive anode structure 10 in the whole water, prevent overheating during operation and affect electrical characteristics, and When the soaking liquid 15 is configured to be in contact with the outside air, it may further carry away a part of the heat by evaporation to impose a heat dissipation and cooling effect.

In practical applications, the underwater conductive anode structure 10 of the present invention can be electrically connected to the insoluble anode 51 of the main plating unit 50 as described above, while the conductive anode structure 10 in the water is further electrically connected to the anode of the external power source 40 by means of an electrically conductive line, and The cathode 53 of the main plating unit 50 is electrically connected to the negative electrode of the external power source 40. Therefore, when the external power source 40 supplies power, the current I from the anode of the external power source 40 flows to the insoluble anode 51 of the main plating unit 50 via the underwater conductive anode structure 10 of the present invention, and the insoluble anode 51 oxidizes the water in the plating solution 57. And oxygen is generated, and the copper ions in the plating solution 57 are at the cathode. 53 is reduced to metallic copper to precipitate, and at the same time, the current I from the cathode 53 further flows to the negative electrode of the external power source 40, thereby forming an electrically connected circuit in which the current I of the drawing shows the flow of current.

Since the copper ions in the plating solution 57 are lost due to electroplating, in order to supplement the copper source, copper oxide powder can be directly added to the plating solution 57, since the copper oxide can be easily dissolved in the sulfuric acid-containing plating solution 57.

To further enhance the cooling function of the soaking liquid 15, the present invention may include a circulation line (not shown) and a circulation pump (not shown), wherein the circulation pump is connected to the circulation line, and the circulation line is connected to each The conductive container 11 allows the soaking liquid 15 accommodated in the conductive container 11 to flow through each other, and the soaking liquid 15 is driven by the circulation pump. Further, the soaking liquid 15 may be pumped away from the conductive container 11 by a circulation pump, such as when the soaking liquid 15 is contaminated, or when too much copper sulfate from the plating liquid 57 is contained.

In summary, the present invention is characterized in that the fixing element is used to lock the insoluble anode to the conductive container, and the soaking liquid in the conductive container is used to provide heat dissipation and cooling, thereby effectively maintaining the plating quality and solving the bubble. The plating solution brought out is caused by the precipitation of copper sulfate, and the resistance is prevented from increasing.

The above is only a preferred embodiment for explaining the present invention, and is not intended to limit the present invention in any way, and any modifications or alterations to the present invention made in the spirit of the same invention. All should still be included in the scope of the intention of the present invention.

10‧‧‧Water conductive anode structure

11‧‧‧Electrical container

13‧‧‧Fixed components

15‧‧‧ soaking solution

40‧‧‧External power supply

50‧‧‧Main plating unit

51‧‧‧Insoluble anode

53‧‧‧ cathode

55‧‧‧Main plating bath

57‧‧‧ plating solution

59‧‧‧Agitator

59a‧‧‧ gas injection machine

59b‧‧‧Injection tube

B‧‧‧ bubble

I‧‧‧current

Claims (7)

An underwater conductive anode structure for serially connecting an external power source and a main plating unit for supplying electric power, and the main plating unit comprises at least one insoluble anode, at least one cathode, one main plating tank and one plating a liquid, each insoluble anode has a hook-shaped front end, the plating solution is accommodated in the main plating tank, and the plating solution contains at least hydrogen ions and metal ions, and the metal ions include copper ions, nickel ions, zinc ions and At least one of the chromium ions, and the insoluble anode and the cathode are immersed in the plating solution, the stirring device is for stirring the plating solution, wherein the conductive anode structure in the water comprises: a soaking liquid, Pure water or tap water; at least one fixing element, electrically conductive; and at least one conductive container, electrically conductive, and each conductive container is a grooved strip or a U-shaped strip, which is used for The soaking liquid is disposed, the hook-shaped front end of the insoluble anode is hooked to the inner side of the conductive container, and the insoluble anode is locked to the conductive container by the fixing member, and the fixing is partially a component and a portion of the hook-shaped front end of the insoluble anode are immersed in the soaking liquid; wherein a positive electrode of the external power source is electrically connected to the conductive container via an electrically conductive wire, and the electrically conductive wire is composed of the fixing component And locking to the conductive container, the cathode of the main plating unit is electrically connected to a negative pole of the external power source, so that when the external power source supplies power, the main plating unit reduces copper ions in the plating solution to metal copper. Precipitated on the cathode. The underwater conductive anode structure according to claim 1, wherein the conductive container is made of copper or a copper alloy. The underwater conductive anode structure according to claim 1, wherein the fixing member is made of copper or a copper alloy. The underwater conductive anode structure according to claim 1, wherein the fixing component is realized by an expansion screw, and the screw comprises an upper sleeve and a lower sleeve, and the upper sleeve and the lower portion The sleeve body has a beveled surface which is adhered to each other, and the screw is integrated into the upper sleeve body and the lower sleeve body, so that the inclined surface of the fitting provides an outward pressing function. The underwater conductive anode structure according to claim 1, further comprising a circulation line and a circulation pump, wherein the circulation pump is connected to the circulation line, and the circulation line is connected to each of the conductive containers. The soaking liquids contained in the conductive containers are caused to flow through each other, and the circulating pump is used to drive the soaking liquid. The underwater conductive anode structure according to claim 1, wherein the insoluble anode is composed of titanium, titanium plated platinum, titanium plated metal/corrosion resistant metal passivation layer, or corrosion-resistant conductive non-metal, and the anti-metal is formed. Corrosive conductive non-metallic systems include graphite. The underwater conductive anode structure according to any one of claims 3, 4, and 6, wherein the fixing element is attached to the insoluble anode or attached to the conductive container.