CN112593267B

CN112593267B - Electroplating equipment

Info

Publication number: CN112593267B
Application number: CN202011274920.4A
Authority: CN
Inventors: 吴勇军
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2022-04-29
Anticipated expiration: 2040-11-13
Also published as: CN112593267A

Abstract

The invention provides electroplating equipment, which comprises an electroplating tank body, a spray pipe, a pump and an anode, wherein the pump is arranged behind the anode, and an insulating shielding plate is arranged between the spray pipe and the anode, wherein the insulating shielding plate shields the anode, so that a power line generated by the anode overflows from the rear side of the anode after being shielded by the insulating shielding plate and is sucked into the spray pipe through the pump. In the electroplating equipment, the insulating shielding plate is arranged between the spray pipe and the anode, so that electric power lines overflow from the rear side of the anode after being shielded by the insulating shielding plate and are sucked into the spray pipe through the pump, the distribution of the electric power lines is adjusted through solution spraying of the nozzle arranged on the spray pipe, and the uniform distribution of the electric power lines is realized.

Description

Electroplating equipment

Technical Field

The invention relates to the technical field of circuit boards, in particular to electroplating equipment.

Background

With the increasing demand of high-density PCBs, the line width/spacing requirements of 50/50um, 35/35um, 15/15um and the like have gradually developed a trend for high-precision circuits, and the thickness difference of the existing electroplated copper is 8-10 um. The line width difference of different positions can reach 10-15um under the requirements of the same line width and 50um spacing. In order to reduce the difference of surface copper, the requirement of the uniformity of the thickness of the electroplated copper is gradually changed from the initial range (maximum-minimum plate surface) of 10um to 8um and 6 um. Wherein the requirement of the carrier plate product reaches 3 um. In order to meet the higher demand of products, deep research on electroplating equipment is required to improve the uniformity of copper thickness.

Aiming at the traditional vertical gantry plating line equipment, the soluble anode is matched with different inherent flying target grooves in copper thickness uniformity, the inherent defects of different anode types can not meet the requirements of PCB products, and the vertical continuous plating line becomes novel mainstream equipment.

In the conventional cathode and anode design of the vertical continuous electroplating copper bath insoluble anode, as shown in fig. 1, during the electroplating of the insoluble anode copper bath, insoluble anodes (titanium mesh or titanium plate) 2 are respectively set on both sides of the PCB (specifically, behind the nozzle 3). In the process of moving paths of positive and negative ions between an anode and a PCB in the electroplating process, electric lines of force are concentrated at the edge and the tip of the cathode PCB (such as an electric line schematic route shown by a reference numeral 1), namely the phenomenon that the electric lines are densely plated with copper and too thick at the edge, the edge angle and the tip is large in current density, namely the phenomenon is called as tip effect or edge effect, and the distribution of the electric lines of force in a normal tank body is shown in a figure 2, so that the condition that two sections in the middle are sparse and dense is met. And the edge of the PCB is caused by local edge effect, so that the plate surface has the conditions of thinner middle and thicker periphery.

To solve the problem of the copper thickness distribution caused by the tip and edge effects, the following two methods and aspects are generally used for optimization:

1. and (3) cathode protection method: for example, the edge part of the electroplated part adopts a copper wire to consume part of the current.

2. A shielding method: for example, the sharp corner is shielded by an insulator during electroplating, and the sharp corners of the anode and the cathode are shielded by the insulator, such as a cathode shield 4 and an anode shield 5 shown in fig. 1.

However, the two design methods are still difficult to meet the higher requirement for the uniformity of the copper thickness, and the optimization of the two design methods is urgently needed.

Disclosure of Invention

In order to solve the technical problem, the invention discloses electroplating equipment which comprises an electroplating tank body, a spray pipe, a pump and an anode, wherein the pump is arranged behind the anode, and an insulating shielding plate is arranged between the spray pipe and the anode, wherein the insulating shielding plate shields the anode, so that electric lines generated by the anode overflow from the rear side of the anode after being shielded by the insulating shielding plate and are sucked into the spray pipe through the pump.

Furthermore, the anode is a titanium plate, the middle part of the insulating shielding plate is provided with a hollow design, so that part of electric lines directly act on the PCB to be plated, and the rest of electric lines flow around the back of the anode and enter the spray pipe.

Further, the anode is a titanium plate, and the insulating shielding plate is fully shielded, so that all electric force lines bypass from the back of the anode and enter the spray pipe.

Further, the area of the opening of the hollow design accounts for 10% -50% of the area of the insulating shielding plate.

Furthermore, the anode is a titanium mesh, the insulating shielding plate is provided with a windowing design with blank spaces, and the size of the blank spaces is the same as or 1% -30% smaller than the gap of the titanium mesh, so that all power lines flow around from the back of the anode and enter the spray pipe.

Furthermore, the electroplating equipment is provided with two groups of spray pipes for respectively plating two surfaces of the PCB to be plated, wherein the back of the two groups of spray pipes is respectively provided with the insulating shielding plate and the anode.

Further, an insulating shielding part is arranged at the position of the peripheral edge of the anode.

Furthermore, an upper adjustable insulating shielding component and a lower adjustable insulating shielding component are arranged at the upper edge and the lower edge of the anode.

Further, the four right angles of the anode are subjected to round angle or corner cutting treatment.

In the electroplating equipment, the insulating shielding plate is arranged between the spray pipe and the anode, so that electric power lines overflow from the rear side of the anode after being shielded by the insulating shielding plate and are sucked into the spray pipe through the pump, the distribution of the electric power lines is adjusted through solution spraying of the nozzle arranged on the spray pipe, and the uniform distribution of the electric power lines is realized.

Drawings

FIG. 1 is a side view of a plating tank body of the plating apparatus;

FIG. 2 is a top view of the tip effect of the PCB board;

FIG. 3 is a schematic view of an anode titanium plate and an anode titanium mesh, respectively;

FIG. 4 is a side view showing a partial structure of an electroplating apparatus of the present invention;

FIG. 5 shows a schematic view of an insulating shroud for an anode titanium plate and titanium mesh;

FIG. 6 is a front view of the anode insulating barrier design of the present invention;

FIG. 7 is a schematic view of the anode insulating shutter according to the present invention.

Detailed Description

The technical solution of the present invention will be further described with reference to the following specific examples, but the present invention is not limited to these examples.

As shown in fig. 3, the conventional copper bath insoluble anode forms are divided into two types: titanium plates and titanium mesh. In order to improve the uniformity of the plating process on the surface of the board, it is necessary to improve the distribution of the electric lines inside the plating tank, as shown in fig. 1, the bottom shielding is usually added on the anode side of the bottom of the PCB, the bottom shielding is added on the cathode side of the PCB, and some shielding is also added on the top of the PCB, in order to reduce the local over-thickness caused by the tip effect due to the excessive electric lines on the bottom. This can be understood as a process of subtracting the power line. However, the process is usually confronted with disturbance interference of the bottom solution, the anode power line is simply shielded, the power line can not disappear only in a process that one traveling route is disturbed and redistributed, and on the contrary, the process shutter parameter setting, the anode side bottom shutter parameter adjustment and the like are added, so that the size of the jet flow of the spray pipe is varied in multiple parameters, and the uniformity adjustment is more difficult. For this reason, optimization is required for the distribution manner of the anode power lines.

In the present invention, a design concept of complete subtraction of power lines is proposed to optimize the distribution of power lines. Specifically, as shown in fig. 4, a design of insulating and shielding the anode 2 near the PCB to be plated is proposed, so that the power lines are all overflowed from the rear side of the anode after being shielded, and then sucked into the nozzle through the pump at the back, so that the distribution of the power lines is adjusted by spraying the solution through the nozzle arranged on the nozzle. Therefore, the invention realizes the uniform distribution of the power lines by turning the power lines comprehensively and then by magnetron sputtering, which is completely different from the traditional electric field for realizing the distribution of the power lines.

To this end, the invention proposes an electroplating apparatus comprising: electroplating cell body, spray tube, pumping and positive pole 2, the pumping sets up behind the positive pole the spray tube with be provided with insulating sunshade 10 (or spray tube and insulating sunshade parallel and level) between the positive pole 2. Wherein the insulating shielding plate 10 shields the anode 2, so that electric lines of force generated by the anode 2 are shielded by the insulating shielding plate 10, and then overflow from the rear side of the anode 2 and are sucked into the spray pipe through the pump.

In order to meet the requirement of double-sided plating of the PCB, as shown in FIG. 4, two groups of nozzles are arranged in the electroplating tank body to plate two sides of the PCB to be plated respectively, each group of nozzles is a plurality of nozzles which are uniformly distributed, wherein the distance between the nozzles is 80-150 mm. In this case, an insulating shroud and an anode are provided behind the two sets of nozzles, respectively.

For the insulating shielding of the anode, slight differences in design are possible for different forms of anode, such as titanium mesh and titanium plate.

Referring to fig. 5 (a), there is shown a schematic view of an insulating shield for an anode titanium plate. The middle part of the insulating shielding plate of the anode titanium plate is provided with a hollow design, so that part of electric lines directly act on the PCB to be plated, and the rest of electric lines are turned and then sucked into the spray pipe through the pump and sprayed out through the nozzle to act on the surface of the PCB.

In a specific embodiment, the area of the opening in the hollow design may occupy 10% to 50% of the area of the insulating shield.

Alternatively, the insulating shroud may be fully shrouded for the anode titanium plate so that all of the electric field lines bypass the anode and enter the lance.

Referring to fig. 5 (b), a schematic view of an insulating shield for an anode titanium mesh is shown. The insulating shielding plate of the anode titanium mesh needs to be designed to be fully windowed, and particularly is provided with spaces which are as large as gaps of the titanium mesh or 1% -30% smaller than the gaps of the titanium mesh, so that all power lines flow around from the back of the anode into the spray pipe and act on the plate surface.

Further, in consideration of the edge effect around the anode, for complete uniformity of the electric field lines, as shown in fig. 6, the present invention also proposes the following improvements with respect to the arrangement of the anode:

(1) the peripheral edge position of the anode (titanium mesh or titanium plate) is designed in an insulating way, for example, shielding plates made of insulating materials can be respectively arranged at the upper edge position, the lower edge position, the left edge position and the right edge position so as to carry out insulating covering shielding.

Because in actual production, the size of the PCB to be plated is different, the requirement for the height of the insulating shielding of the anode is also changed. In view of this, in order to meet more different production line requirements, the insulating shielding plates disposed at the upper and lower edge positions of the anode may adopt an insulating shielding member (or an insulating shielding plate movable up and down) with an adjustable up and down position, thereby realizing adjustment of the anode shielding height.

For example, referring to fig. 7, there is shown a schematic view of the structure of the anode insulating shroud of the present invention. Wherein the size of the exposed part 21 of the anode titanium mesh is adjusted by a movable adjusting device 22, and the reference numeral 23 shows the maximum area of the anode titanium mesh which can be exposed.

(2) The four right angles of the anode (titanium mesh or titanium plate) are processed by round corner or chamfer to reduce the anode tip effect generated by the right angles of 90 degrees to cause local concentration of the power lines.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept of the present invention, and these changes and modifications are all within the scope of the present invention.

Claims

1. An electroplating device comprises an electroplating tank body, a spray pipe, a pump and an anode, and is characterized in that the pump is arranged behind the anode, and an insulating shielding plate is arranged between the spray pipe and the anode, wherein the insulating shielding plate shields the anode, so that electric power lines generated by the anode overflow from the rear side of the anode after being shielded by the insulating shielding plate and are sucked into the spray pipe through the pump,

the anode is a titanium plate, and the insulating shielding plate is fully shielded, so that all power lines flow around from the back of the anode and enter the spray pipe; or

The anode is a titanium mesh, the insulating shielding plate is provided with a windowing design with blank spaces, and the size of the blank spaces is the same as or 1% -30% smaller than the gap of the titanium mesh, so that all power lines flow around the back of the anode and enter the spray pipe.

2. The electroplating apparatus according to claim 1, wherein the electroplating apparatus is provided with two sets of nozzles for respectively plating both sides of a PCB to be plated, wherein the insulating shield and the anode are respectively provided behind the two sets of nozzles.

3. The plating apparatus as recited in claim 1, wherein an insulating shield member is provided at a position of a peripheral edge of said anode.

4. The plating apparatus as recited in claim 1, wherein upper and lower adjustable insulating shield members are provided at upper and lower edge positions of the anode.

5. The plating apparatus as recited in claim 1, wherein four right angles of the anode are rounded or chamfered.