KR20030073398A - Reverse fountain type plating apparatus - Google Patents

Abstract

PURPOSE: A reverse fountain type plating apparatus is provided in which precision plating is enabled even at a bumper higher than a flat plate or wafer having narrow and deep trench, and manual operation is not necessary so that defects due to dust adhered to workpiece is fundamentally prevented. CONSTITUTION: In a plating apparatus comprising a plating pot(1) in which plating solution is contained, a pump(6) for supplying plating solution filtered by filter(7) into the plating pot(1) through pipe(8) in a certain pressure, and a power supply(5) for supplying direct current power to the plating solution and object to be plated(4), the reverse fountain type plating apparatus is characterized in that the plating pot(1) is sealed by chamber(2), a jig(3) for setting the object to be plated(4) is installed with being spaced apart in a certain distance from the lower part of the plating pot(1) on which discharge holes(12) are formed, and the plating solution is sprayed onto the upper part of the plating pot(1) through sparger(21) installed at an end of the pipe(8), wherein a vertically movable cylinder is mounted on the lower part of the jig(3), wherein a rotational motor is mounted on the lower part of the jig(3), and wherein a vibrator is mounted on the lower part of the jig(3).

Description

Reverse fountain type plating apparatus

The present invention relates to a flat plate plating apparatus that enables effective electroplating in a constant tank, and more particularly, to a reverse type plating apparatus for plating a plated body by supplying an electrolytic solution for plating from above.

Small electric and electronic parts and special parts are prevented from being rusted to prolong their lifespan, and also to electroplate special materials to improve the function of parts as well as to reduce resistance due to the characteristics of parts. After the circuit design, Wafer is plated to protect the circuit by making a bump or filling a trench.

However, in general plating, a plating solution suitable for the property of a metal to be plated is put in a plating bath, a workpiece is suspended on a cathode, and a plating metal is suspended on a cathode, immersed in a plating solution and energized. As the fine particles of the plated metal are reduced on the cathode side and deposited on the surface of the plated body, the metal particles are firmly attached to the plated metal. After time passes, plating may not proceed at all.

Therefore, in the related art, an apparatus for excluding bubbles by mainly discharging bubbles or moving workpieces by stirring the electrolyte solution during plating is mainly used, but they have a drawback that they are not suitable for precision gold.

Thus, a more advanced apparatus has been developed, in which a rack type plating apparatus as schematically shown in FIG. 5, one of such apparatuses, installs a rack 11 in a plating bath 1, Then, the plating liquid filtered by the filter 7 is ejected into the plating bath 1 at a predetermined pressure by using the pump 6 installed outside the plating bath 1 while the plated body 4 is energized. The plating solution to be flowed is collected through the collecting path 13 and forced to reflux again, so that bubbles or the like are not adhered to the plated body 4, and as another device, a classification developed for more precise plating ( There is a fountain type plating apparatus, which is mounted on the upper end of the plating bath 1, as shown in FIG. 6 (the plating body 4 is not locked in the plating bath 1). Pump on the outside of the plating bath (1) 6) through the pipe (8) connected to the lower end of the plating bath (1) so that the plating liquid is ejected to the plated body 4 and overflows, which is precisely designed lines and trenches such as semiconductor wafers It is suitable for plating while filling (Trench) and has been preferred as a plating apparatus for flat wafers.

However, even with the most advanced type of plating system, the problem of plating is difficult for 30 cm large flat wafers, which is because the bumps of the wafers are high and the trenches are narrow and deep, so that the bubbles supplied with the plating liquid sorted in between are stagnant. It is due to the easy to be.

The present invention was developed as a result of research to provide a new type of plating apparatus capable of precision gold under the above-mentioned environment, and provides an apparatus that enables precision gold even on wafers having a high bumper or a narrow and deep trench from a flat plate. In addition, the plating apparatus prevents defects caused by dust adhering to the material by eliminating manual operation so that plating is performed in a clean environment, and in particular, to complete the present invention to make such an apparatus simple and economical. It will now be described in detail with reference to the drawings.

1 is a configuration diagram of the present invention,

2 is a schematic cross-sectional view of a configuration state of the present invention;

3 is a schematic cross-sectional view of another configuration state of the present invention;

Figure 4 is a schematic cross-sectional view of another configuration state of the present invention,

5 is a configuration diagram of a conventional invention,

6 is a configuration diagram of another conventional invention.

* Explanation of the Major Codes in Drawings

1. Plating bath

Rack (cathode) 12. Discharge hole 13. Recovery

2. Chamber

21.Ejector

3. Jig

31.Cylinder Motor 33. Carbon brush

34. Vibrator

4. The plated body 5. Power Supply

6. Pump 7. filter

8. Pipe

81.Valve

1 is a diagram illustrating a configuration of the present invention, and FIG. 2 is a diagram schematically illustrating a configuration of the present invention in cross section.

The present invention provides a plating bath (1) containing a plating solution, a pump (6) for supplying the plating solution filtered by the filter (7) to the plating bath (1) at a predetermined pressure through a pipe (8), a plating solution and a plated object. In the plating apparatus which consists of the power supply 5 which supplies DC power to the sieve 4, the said plating tank 1 is sealed by the chamber 2, and the discharge hole 12 is provided in the lower end of the plating tank 1; Jig (3) is installed is set to the plated body (4) at intervals in which the (2) is formed, the plating solution of the plating tank (1) through the ejector 21 is installed at the end of the pipe (8) Characterized by being made to be sprayed from the top.

3 is a schematic cross-sectional view of another configuration state of the present invention.

In the above-described configuration, it is more preferable that the cylinder 31, which can be moved up and down, is attached to the lower end of the jig 3.

Figure 4 is a schematic cross-sectional view of another configuration state of the present invention,

In the above configuration, it is more preferable that the rotary motor 32 is mounted at the lower end of the jig 3.

In the above configuration, it is more preferable that the vibrating vibrator 34 is attached to the lower end of the jig 3.

Referring to the effects of the present invention made as described above are as follows.

According to one configuration of the present invention, a plating tank 1 containing a plating liquid, a pump 6 for supplying the plating liquid filtered by the filter 7 to the plating tank 1 through a pipe 8 at a predetermined pressure; On the basis of the conventional plating apparatus consisting of a power supply (5) for supplying a direct current power to the plating liquid and the plated body (4), the plating bath (1) is sealed by a chamber (2), the plating At the lower end of the tank 1, a jig 3 in which the plated body 4 is set is provided at intervals at which the discharge holes 12 are formed, and the plating liquid is ejected at the end of the pipe 8 ( 21 to be sprinkled from the upper end of the plating bath 1, the plated body 4 is set on the jig 3 and the positive electrode of the DC power supply in the power supply 5 is the plating solution side (separate electrode May be supplied to the plating bath 1 without using a negative electrode. 1) When the plating solution is opened, the plating solution is sprinkled on the pipe 8 from the upper end of the plating bath 1 to the shower in the ejector 21, and the discharge hole 12 is formed at the lower end of the plating bath 1. Since the plated body 4 is set at intervals, or because it is installed, the plating liquid flows into the lower end of the chamber 2 through the discharge hole 12 and is collected and rectified in the plating bath 1, and pumped. At 6, the plated body 4 set on the jig 3 of the negative electrode is charged with the negative electrode to be plated, and the plated body 4 is plated by a plating solution. As in the conventional classification, bubbles that may be caught between the bumps or between the trenches naturally float to prevent plating defects (Void phenomenon), and in particular, the plating solution is ejected from the upper surface into the shower to form a plating bath. Oil refined in (1) and then flows into discharge hole (12). It is possible to further improve the efficiency.

In addition, the chamber 2 is simply described as being hermetically sealed. Here, the hermetic seal is intended to prevent the plating liquid back-classified into the shower from leaking in the chamber 2, but the sealing force is further increased and the negative pressure in the chamber 2 is reduced. Pressure (vacuum) is applied to degassing bubbles easily between bumps and trenches, which can be expected to reduce defect rate and improve plating efficiency. It is obvious that the skilled person is within the technical scope of the present invention since it is merely a design change that can be selectively employed.

According to another configuration of the present invention, in addition to the above-described configuration, a cylinder 31 that can be moved up and down is mounted on the lower end of the jig 3, and thus the cylinder 31 mounted on the lower end of the jig 3 is upward. The lowering is to facilitate the setting of the plated body 4. For example, when the jig 3 is lowered with the cylinder 31 to increase the distance between the plating bath 1 and the jig 3, the flat wafer and This is because the same to-be-plated body 4 is easily held in and out of the state of being held by a loader in a state held by a worker's hand.

According to another configuration of the present invention, in addition to the above configuration, the rotary motor 32 is mounted on the lower end of the jig 3, which causes the motor 32 to spin the jig 3 to be plated. In order to make the plating evenly on all sides of the sieve (4), at the bottom of the jig (3) to be rotated is a carbon brush 33 is installed is required to prepare to ensure that there is no abnormal power supply during rotation, this application It is obvious that other modifications do not depart from the technical scope of the present invention.

In addition, even if the motor 32 is installed together with the cylinder 31, there is no problem in operation. In this case, the cylinder 31 is configured to shift the spin motor 32 together, or the spin motor 32 is a cylinder. The 31 may be rotated together or any structure may be adopted.

According to another configuration of the present invention, in addition to the configuration described above, the vibrating vibrator 34 is mounted on the lower end of the jig 3, which gives a slight vibration to the plated body 4, so that bubbles are well formed. It is possible to make it possible to reliably avoid voids caused by bubbles so that high quality plating can be achieved. The vibrator 34 also vibrates the plated body 4 directly by using a known vibrator or vibrator, or The vibrating jig 3 supporting the plated body 4 may be adopted to vibrate the plated body 4 together, but the relative vibration between the plated body 4 and the jig 3 may be adopted. The latter is preferable in order to avoid scratching by the like.

An Example is given to the following and this invention is demonstrated.

Examples 1 and 2

The 8-inch flat plate wafer is set in the plating apparatus of the present invention using a Sn / Pb plating solution (the most commonly used commercially available solution) at room temperature, and solder plating for making a bumper at a current density of 2 A / dm ( Solder coating) and cupper coating (Cupper Coating) filling the trench were performed for 5EA each.

The results are shown in the table.

Comparative Examples 1 and 2

In the rack type plating apparatus and the split type plating apparatus, 3EA each of a solder and a cupper was performed on the same conditions as Example 1, respectively.

The results are shown in the table.

table

Condition Inspection evaluation Bubble formation point Balance of Coating Thickness Example 1 (solder plating) Room temperature, Sn / Pb plating solution Current density 2A / dm 0 ◎ Extremely good Example 2 (Copper Plating) 0 ◎ Extremely good Comparative Example 1 (Rack Type Plating) Solder plating 6 △ Not suitable for use Cupper plating 8 × Extremely poor Comparative Example 2 (Classification Type Plating) Solder plating 3 ○ Great Cupper plating 5 △ Not suitable for use

The wafers of 5EA and 3EA fabricated in Examples and Comparative Examples were visually inspected to count voids generated by bubbles and averaged (less than 1), and the film thickness was randomly checked at five locations of each wafer. All points are marked with ◎ when they have an error within 3% of the thickness, ○ when within 5%, △ when within 10%, and × when they deviate by 10% even at one point.

It was judged that all were extremely excellent in the Example, and in the rack type of the comparative example 1, it became defect by the void by the bubble in a trench.

As described above, the present invention was developed as a result of researches to provide a new type of plating apparatus capable of precision plating under any circumstances, and has been developed to enable precision machining even on wafers having high bumpers or narrow deep trenches from flat plates. The present invention provides an apparatus, and the plating apparatus prevents defects caused by dust adhering to the material by eliminating manual operation so that plating is performed in a clean environment, and in particular, an effective invention for making such a device simple and economical. to be.

Claims (4)

The present invention provides a plating bath (1) containing a plating solution, a pump (6) for supplying the plating solution filtered by the filter (7) to the plating bath (1) at a predetermined pressure through a pipe (8), a plating solution and a plated object. In the plating apparatus which consists of the power supply 5 which supplies DC power to the sieve 4, The plating bath 1 is sealed with a chamber (2), At the lower end of the plating tank 1, a jig 3 in which the plated body 4 is set is provided at intervals at which the discharge holes 12 are formed. The plating liquid is a reverse classification plating apparatus, characterized in that the plating liquid is made to be sprayed from the upper end of the plating bath (1) through the ejector (21) installed at the end of the pipe (8). The method of claim 1, Reverse type plating apparatus, characterized in that the upper and lower cylinder 31 is mounted on the lower end of the jig (3). The method according to claim 1 or 2, Reverse type plating apparatus, characterized in that the rotary motor 32 is mounted to the lower end of the jig (3). The method according to claim 1 or 2, Reverse type plating apparatus, characterized in that the vibration vibrator 34 is mounted on the lower end of the jig (3).