JP2798517B2 - Wafer plating equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer plating apparatus for plating a semiconductor wafer.

[0002]

2. Description of the Related Art A conventional wafer plating apparatus as shown in FIG. 5 is known. This wafer plating apparatus is provided with a cup-shaped plating tank 1 in which a plating solution L supplied from a lower supply unit 1s squeezed into a funnel overflows from an upper opening 1p. The plating is performed by bringing the plating solution L into contact with the wafer U placed on the opening 1p of the tank 1. For mounting the wafer U, a cathode electrode 2 whose tip is sharpened in a pin shape is used. The cathode electrode 2 is provided in the plating tank 1 so as to be always in contact with the plating solution L. Reference numeral 3 denotes an anode electrode, and the plating solution L is supplied through a large number of through holes 3h formed in the anode electrode 3.

Although this wafer plating apparatus is excellent in that a flat wafer can be efficiently plated, there are still some insufficient points. That is,. Since the cathode electrode is in the plating solution, plating is deposited there. . Unnecessary plating is performed due to the plating solution flowing around the side surface and the back surface of the wafer. . The contact with the cathode electrode is unstable.

[0004] One of the techniques proposed to improve these points is, for example, the technique disclosed in Japanese Utility Model Laid-Open No. 2-38472. In this technique, a wafer is pressed and fixed on a plate-shaped cathode (cathode electrode) with a conductive buffer plate interposed therebetween. With such a structure, the side and back surfaces of the cathode electrode and the wafer are separated from the plating solution. The above point has been solved by being able to seal. However, this structure requires a plate-shaped cathode and a conductive buffer plate, and in particular, the conductive buffer plate requires a complicated structure in which a conductive member is combined, resulting in a large cost increase. Have a factor.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the disadvantages of the above-mentioned conventional device with a simpler structure.

[0006]

In order to achieve the above object, a wafer plating apparatus according to the present invention is provided with an elastic member at an arrangement receiving portion formed at an opening of a plating tank. Along with the wafer being pressed against and arranged, between the elastic member and the wafer, the tip of the cathode electrode formed thin in a flat state,
The cathode electrode is sandwiched so as not to contact the plating solution.

In this wafer plating apparatus, the wafer is pressed against the elastic member arranged in the arrangement receiving portion and arranged so as to seal the side surface and the back surface of the wafer from the plating solution, and the elastic member and the wafer are arranged. By sandwiching the front end of the cathode electrode between the first electrode and the second electrode, the sealing of the cathode electrode against the plating solution and the stability of contact of the cathode electrode with the wafer are realized. In other words, this wafer plating apparatus improves the disadvantages of the conventional apparatus.
Only an elastic member having a simple structure is added as a member, and an extremely simple structure that does not require a complicated structure at all is also required for the combination of members.

In such a wafer plating apparatus, the elastic member can be provided in a state corresponding to the entire circumference of the wafer, that is, in a state in which the entire circumference of the wafer is sealed. If there is a portion that requires plating, a plurality of elastic members may be provided in portions where plating is not required.

Furthermore, if the arrangement receiving portion is made detachable from the opening of the plating tank, the wafer size can be changed simply by changing the arrangement receiving portion without changing the plating tank. Can increase the quality.

[0010]

Embodiments of the present invention will be described below. In the following description, the same parts as those in the above-described conventional example are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. This wafer plating apparatus 10 is formed such that an arrangement receiving portion 11 projects inwardly like an eave in an opening 1p of a plating tank 1. The arrangement receiving portion 11 is detachably attached to the opening 1p of the plating tank 1.
According to the size of the wafer U, it is possible to cope with a change in the size of the wafer U simply by exchanging it with a different protrusion size to the inside. Further, an elastic member 12 is provided in the arrangement receiving portion 11. And
The wafer U is placed in a state of being pressed against the elastic member 12 by a pressing member (not shown), and the entire circumference thereof is sealed with the plating solution L with a predetermined width in a state as shown in FIG. Have been in a state to be.

Further, the tip of the cathode electrode 13 is held between the wafer U and the elastic member 12. The tip of the cathode electrode 13 is formed by unwinding a bundle of fine wires and flattening, and is sunk into the elastic member 12 by the elasticity of the elastic member 12, and is completely sealed with the plating solution L (FIG. 2). In addition, the cathode electrode 13 is brought into contact with the wafer U reliably and stably.
In this example, as shown in FIG.
Although the number is provided, this number is appropriately selected in relation to the current capacity. However, a plurality of cathode electrodes 13
Is preferably provided symmetrically for uniform plating.

Further, the anode electrode 14 is also devised. That is, in order to eliminate the stagnation of the circulating flow by making the central part of the flow of the plating solution L circulating in the plating tank 1 stronger than the peripheral part, the diameter of the through-hole 14h increases from the periphery to the center. I'm trying to get bigger.

In the above embodiment, the elastic member 12 seals the entire circumference of the wafer U. However, when there is a portion that needs plating around the wafer U, the "elastic member" is used. Is provided in a so-called finely divided manner, and the "elastic member" of the finely divided piece is provided corresponding to a portion that does not require plating.

[0014]

As described above, the wafer plating apparatus according to the present invention, by arranging the wafer by pressing it against the elastic member provided on the arrangement receiving portion, allows the plating solution on the side and back surfaces of the wafer to be removed. Since the tip of the cathode electrode is sandwiched between the elastic member and the wafer, the sealing of the cathode electrode against the plating solution and the stability of the contact of the cathode electrode with the wafer are realized. In general, only an elastic member having a simple structure is added, and the combination of members can be eliminated with a very simple structure that does not require a complicated structure at all. In addition, since the arrangement receiving portion is detachable from the plating tank, it is possible to cope with a change in the size of the wafer only by replacing the arrangement receiving portion without changing the plating tank, thereby increasing the versatility of the apparatus.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a wafer plating apparatus according to the present invention.

FIG. 2 is a partial sectional view showing a cathode electrode sandwiched between an elastic member and a wafer.

FIG. 3 is a plan view showing a state where a wafer is sealed by an elastic member.

FIG. 4 is a perspective view showing an upper end portion of the wafer plating apparatus shown in FIG.

FIG. 5 is a side view of a main part of a conventional wafer plating apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Plating tank 1p ... Opening 10 ... Plating device for wafer 11 ... Placement receiving part 12 ... Elastic member 13 ... Cathode U U ... Wafer

Claims (4)

(57) [Claims] 1. A wafer plating apparatus in which a plating solution in a flowing state is brought into contact with a wafer disposed in an opening of a plating tank to perform plating, wherein an elastic member is provided on an arrangement receiving portion formed in the opening of the plating tank. And a wafer is pressed against the elastic member so as to be arranged, and between the elastic member and the wafer, the tip of the cathode electrode formed thin in a flat state is brought into contact with the plating solution. A wafer plating apparatus characterized by being held so as not to be caught. 2. The plating apparatus for a wafer according to claim 1, wherein the elastic member is provided in a state corresponding to the entire circumference of the wafer. 3. The plating apparatus for a wafer according to claim 1, wherein a plurality of elastic members are partially provided. 4. The plating apparatus for a wafer according to claim 1, wherein the arrangement receiving section is detachable from an opening of the plating tank.