TW201445010A - Substrate plating device - Google Patents

Abstract

The purpose of the present invention is to provide a plating device, whereby it becomes possible to make the flow rate to become uniform in an area located between the bottom of a plating bath and a solution level without the need of providing a circulating pump at the outside of the plating bath, and therefore it becomes possible to form a plating film having a uniform thickness over the entire area of a substrate. A plating device equipped with: a plating bath in which a plating solution is to be placed; a substrate holder which can hold a substrate in such a manner that the substrate can be detached freely; an anode which is arranged so as to face the substrate that is held by the substrate holder; a cross-flow impeller which is arranged rotatablly and in a suspended state on the upstream side of the flow of the plating solution as observed from the substrate side; and a driving means for the cross-flow impeller.

Description

Substrate plating device

The present invention relates to a plating apparatus which immerses a substrate in a plating solution and performs plating on the surface of the substrate.

Conventionally, in a plating apparatus for a semiconductor substrate in which a plating fixture for holding a substrate is vertically provided and a plating solution is poured from a bottom surface of a plating tank and overflows from the surface, it is known that a plating fixture can be provided. A paddle that reciprocates from the anode, and the plating solution is uniformly supplied to all areas of the plated surface of the substrate during the plating process.

In the case where the stirring blade is used for the stirring, the substrate is held by the plating jig, and the stirring blade is reciprocated while the plating process is performed. However, the direction of the liquid flow is opposite to the traveling direction of the stirring blade, and there is a liquid. The flow direction is a problem that alternates and cannot accelerate the flow velocity on the surface.

For this reason, Patent Document 1 discloses a plating apparatus that vortexes a plating solution supplied from a lower portion of a plating tank by a vortex generator that vortexes a plating solution.

However, in the case of the plating apparatus, it is necessary to provide a circulation pump for sending the plating liquid to the vortex generator outside the plating tank, except for the space change. In addition, since the plating liquid is supplied to the vortex generator from the lower portion of the plating tank, it is difficult to make the flow velocity uniform in the upper and lower sides of the surface to be plated.

[Patent Document 1] Japanese Patent Laid-Open No. 2004-345066

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an overcoming of the above-mentioned disadvantages of the conventional plating apparatus, which can provide a flow rate from the bottom of the plating tank to the liquid surface without having to provide a circulation pump outside the plating tank, and can extend over the entire area of the substrate. The plating film thickness is made uniform.

The present invention is directed to a plating apparatus including: a plating tank for accommodating a plating solution; a substrate holder for detachably holding the substrate; and a substrate held by the substrate holder a relatively disposed anode; a cross-flow impeller that is rotatably suspended on the upstream side of the plating liquid flow as viewed from the substrate; and a driving means of the cross-flow impeller.

The plating apparatus of the present invention circulates the plating solution by the cross-flow impeller which is suspended in the plating tank, so that the flow rate can be the same from the bottom of the plating tank to the liquid surface, and can be spread over the entire area of the substrate. To make the plating film thick Be uniform.

Further, since the plating apparatus of the present invention does not require a circulation pump to be provided outside the plating tank, the installation space can be made compact.

1‧‧‧ plating tank

2‧‧‧Substrate holder

3‧‧‧Anode

4‧‧‧ Cross flow impeller

5‧‧‧Interference board

6‧‧‧Interference board

7‧‧‧Rectifier board

41‧‧‧ wing

42‧‧‧Support Department

43‧‧‧Axis

W‧‧‧Substrate

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic plan view of a plating apparatus of the present invention.

Fig. 2 (a) is a front view of a cross flow impeller of a plating apparatus of the present invention, and (b) is a cross-sectional view of a cross flow impeller of the plating apparatus of the present invention.

Figure 3 is a schematic plan view of a different embodiment of the plating apparatus of the present invention.

Figure 4 is a schematic plan view of a different embodiment of the plating apparatus of the present invention.

Hereinafter, an embodiment of the plating apparatus of the present invention will be specifically described based on the drawings. However, the invention is not limited in any way by these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic plan view of a plating apparatus of the present invention. As shown in the figure, the plating apparatus of the present invention comprises a plating tank 1 for accommodating a plating liquid, a substrate holder 2 for detachably holding a substrate, and a substrate W held by the substrate holder 2. The oppositely disposed anode 3; viewed from the substrate, rotatably suspended on the upstream side of the plating liquid flow The flow impeller 4; the driving means (not shown) of the cross flow impeller 4; and the interference plates 5, 6 provided in the vicinity of the cross flow impeller 4. Each member will be described below.

Fig. 2 (a) is a front elevational view of the cross flow impeller 4 of the plating apparatus of the present invention. As shown in the figure, the cross flow impeller 4 of the present embodiment is provided between the upper and lower disc-shaped support portions 42 so as to have a plurality of wing portions 41 radially extending therebetween via the rotating shaft portion. Next, the shaft portion 43 is erected by the upper support portion 42 , and the wing portion 41 is rotatably provided as the rotation shaft. Further, a motor as a rotational driving means of the cross flow impeller 4 is connected to the upper portion of the shaft portion 43. In the present embodiment, as shown in FIG. 2(b), the wing portion 41 is formed in a rectangular cross section, but the shape is not limited thereto. For example, as shown in FIG. 1, the wing portion 41 may be formed to be The direction of rotation of the impeller has a concave arc shape. By providing the concave surface, the wing portion 41 can more efficiently collect the plating liquid to increase the flow rate. Among them, the number of the wings 41 is not particularly limited. Further, it is preferable that the width of the wing portion 41 (the length in the vertical direction on the drawing) is at least the width of the height of the plated surface on which the lid substrate W can be covered.

As shown in FIG. 1, in the plating tank 1, the positional relationship of the cross-flow impeller 4 in the front-rear direction is disposed so as to be located between the substrate W and the anode 3 and the rotation axis thereof is located close to the substrate holder 2, and is laterally The positional relationship is such that the rotation axis of the cross flow impeller 4 is located on the upstream side of the plating liquid flow viewed from the substrate W and is located outside the end portion of the substrate holder 2 .

On the both sides of the cross flow impeller 4, a pair of interference plates 5, 6 which sandwich the cross flow impeller 4 to form a flow path of the plating liquid are placed. specific The interference plate 5 has a flat portion extending from the anode 3 side toward the substrate W side, and a curved surface portion curved from the front end of the flat portion toward the substrate W. Next, the interference plate 6 is closer to the wall surface of the plating tank 1 than the cross flow impeller 4, and is bent so as to be along the outer edge of the cross flow impeller 4. The plating liquid which is reflowed from the anode 3 side in the plating tank 1 by the interference plates 5 and 6 is accelerated by the cross flow impeller 4, and a liquid flow in the direction of the arrow is generated. As described above, in the plating apparatus of Fig. 1, the flow velocity of the plating liquid can be made uniform by the cross-flow impeller 4 on the upper and lower sides of the surface to be plated.

Figure 3 is a representation of various embodiments of the plating apparatus of the present invention. As shown in the figure, in the present embodiment, a space is provided between the anode 3 and the wall surface of the plating tank 1, and a flow path of the plating liquid is formed. Therefore, as indicated by the arrow, the reflow of the plating solution in the plating tank 1 becomes smoother, which is preferable.

Figure 4 is a different embodiment of the plating apparatus of the present invention. As shown in the figure, in the present embodiment, a plurality of rectifying plates 7 are provided at intervals between the substrate holder 2 and the anode 3. The rectifying plate 7 is provided so as to be substantially the entire width of the substrate holder 2 so that the tip end of the interference plate 5 is parallel to the substrate holder 2. The rectifying plate 7 is preferable since the liquid flow in the vicinity of the plated surface of the substrate W is more uniform.

In each of the above embodiments, the cross-flow impeller 4 is provided with one portion on the upstream side of the plating liquid flow viewed from the substrate, but may be additionally formed as two portions on the downstream side of the plating liquid flow. . For example, in each of the above embodiments, it is provided only on the left side of the substrate holder 2 and the anode 3, but it may be provided in a bilaterally symmetrical manner. The substrate holder 2 and the right side of the anode 3 are provided. At this time, the interference plates 5 and 6 are added to the downstream side so that the left and right sides are symmetrical, and the rotation direction of the downstream cross flow impeller 4 is formed to be the same as the upstream side, whereby the plating liquid is applied to the substrate. The flow is formed upstream and downstream of the flow, so that the backflow of the clockwise rotation in the plating tank 1 can be more effectively promoted.

1‧‧‧ plating tank

2‧‧‧Substrate holder

3‧‧‧Anode

4‧‧‧ Cross flow impeller

5‧‧‧Interference board

6‧‧‧Interference board

41‧‧‧ wing

W‧‧‧Substrate

Claims (6)

A plating apparatus comprising: a plating tank for accommodating a plating solution; a substrate holder that detachably holds the substrate; and an anode disposed to face the substrate held by the substrate holder; and viewed from the substrate a cross-flow impeller that is rotatably suspended on the upstream side of the plating liquid flow; and a driving means for the cross-flow impeller. A plating apparatus according to claim 1, wherein the plating apparatus includes a pair of interference plates in which a flow path of the plating liquid is formed by sandwiching the cross flow impeller therebetween. A plating apparatus according to claim 1 or 2, wherein the wing portion of the cross flow impeller has a concave surface in a rotational traveling direction of the impeller. The plating apparatus according to any one of claims 1 to 3, wherein a flow path of the plating solution is formed by providing a space between the anode and a wall surface of the plating tank. The plating apparatus according to any one of claims 1 to 4, wherein a plurality of rectifying plates are provided at a distance between the substrate holder and the anode. The plating apparatus according to any one of the items 1 to 5, wherein the cross-flow impeller is additionally provided on the downstream side of the plating liquid flow as viewed from the substrate.