JPH02292829A - Plating device - Google Patents

Abstract

PURPOSE:To manufacture the title plating device capable of immediately handling wafers in different diameters, increasing the production efficiency further augmenting the freedom in wafer handling process doing no damage to the wafers by a method wherein the plating device is provided with respective specific pallet, carrier and press down means. CONSTITUTION:The title plating device is provided with a pallet 1 for mounting a wafer W and having an opening to expose the plated surface of the wafer W as it is mounted, a carrier 2 elastically supporting the pallet 1 and carrying it between the position immediately above the opening of a plating chamber 4 opening upward and the other position distant from the plating chamber 4, a press down means 3 pressing down the wafer W carried to the position immediately above the plating chamber 4 by the carrier 2 so that the outer periphery of lower surface of the wafer W may be liquid-tightly pressure-welded into an opening edge of the pallet 1 likewise the outer periphery of lower surface of the pallet 1 into the opening edge of the plating chamber 4. For example, an elevating mechanism 5 to lift up the wafer W for taking it out is provided in the position distant from the chamber 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plating apparatus, and more particularly to a plating apparatus used for plating bonding electrodes of semiconductor wafers and the like.

[Prior Art] The schematic structure of a conventional device used for such purposes is explained with reference to FIG. 6. A circulation tank 71 is supported on a pedestal 9 and contains a plating solution. A pump 7 is connected via a valve 72. In the standby state, the plating solution is circulated through the three-way valve 72 and the pipes 73 and 74.

The tank 71 is located in the center of the sealed earthen wall of the circulation tank 71.
A plating chamber 4 is integrally provided in the chamber 4.
is a cylindrical body that opens upward; a jet nozzle 41 with an anode electrode 44 around it is formed on the bottom wall of the cylindrical body, and a discharge port 42 is formed on the side wall of the cylindrical body.

A peripheral wall 49 having a diameter slightly larger than the diameter of the wafer W is formed on the outer periphery of the opening edge of the plating chamber 4, and serves as a wafer holding portion, and a seal 17 provided on the inner periphery of the opening edge.
The wafer W is placed on the cathode electrode 18 with its outer peripheral lower surface in contact with the wafer W.

When plating is to be performed, the wafer W is pressed by a pressing plate 33 that moves downward by ゜ζ by means of a pressing cylinder 31, so as to bring it into close contact with the seal 17. After that, a DC voltage is applied from the power supply 8 between the anode electrode 44 and the cathode electrode 18, the three-way valve 72 is switched, and the plating liquid discharged from the pump 7 is sent to the jet nozzle 41 via the pipe 75. The liquid is ejected into the plating chamber 4. The plating solution is positively charged by the jet nozzle 41, reaches the surface to be plated on the lower surface of the wafer W, and forms a plating layer, and then passes through the discharge port 4.
2 to return to the inside of the circulation tank 71.

The wafer W is supplied to the wafer holding section 49 and taken out after the plating process by a robot arm 54 similarly provided on the pedestal 9.

[Problems to be Solved by the Invention] Incidentally, in the conventional plating apparatus described above, the wafer holder is either completely integrated with the plating chamber or is mechanically connected to the plating chamber by bolts or the like, so it is not possible to handle wafers of different diameters. There is a problem that it is impossible or impossible to respond quickly. Also, since the wafer is removed after processing on the plating chamber, it is impossible to remove the wafer by pushing it out from below. There was a problem in that the wafer could be damaged due to the wafer not being peeled upward due to the claws of the arm or the like.

The present invention solves these problems by being able to immediately handle wafers of different diameters, improving production efficiency, and increasing the degree of freedom in wafer handling.
It is an object of the present invention to provide a tightening device that can be handled without causing damage.

[Means for Solving the Problems] The configuration of the present invention will be described with reference to FIG. 1. A plating apparatus has an opening 1a for placing a wafer W thereon and exposing the surface to be plated on the lower surface of the wafer W in the placed state. The formed pallet 1 and
A carrier 2 elastically supports the pallet 1 and moves between a position directly above the opening of the plating chamber 4 that opens upward and a position away from the plating chamber 4, and a carrier 2 that moves the pallet 1 to a position directly above the plating chamber 4. A pressing means 3 presses the transferred wafer W from above to bring the outer periphery of the lower surface of the wafer W into pressure contact with the edge of the pallet opening 1a and the lower outer periphery of the pallet 1 with the edge of the opening of the plating chamber 4 in a liquid-tight manner. Equipped with

[Operation] In the plating apparatus having the above structure, the wafer W placed on the carrier 2 via the pallet 1 is
The wafer W and pallet 1 are moved to a position directly above the plating chamber 4 and pressed downward by the suppressing means 3.
are brought into fluid-tight pressure contact with each other. In this state, when a plating solution is introduced into the plating chamber 4, a plating layer is formed on the surface to be plated of the wafer W exposed into the chamber 4 through the pallet opening 1a.

After the plating process is completed, the pressure by the pressing means 3 is released, and the carrier 2 moves to a position away from the plating chamber 4. Since the wafer W is not directly above the plating chamber 4, it is possible to take out the wafer W by pushing it up from below, and damage to the wafer W can be prevented.

In addition, by exchanging the pallet 1 placed on the carrier 2, it is possible to immediately handle wafers of different diameters.
If a plurality of carriers 2 are provided so that a desired carrier 2 can be moved onto the plating chamber 4, responsiveness will be further improved.

[Embodiment] In FIG. 1, a circulation tank 71 that opens upward is provided in the left half of a base 91 provided on a pedestal 9, and the plating liquid in the tank 71 is distributed through a three-way valve 72 and a pipe. Road 73,
It is circulated by the pump 7 via the pump 74. The opening of the circulation tank 71 is closed by the plating chamber 4, and the center of the chamber 4 protrudes downward into a cylindrical shape, a jet nozzle 41 is opened at the protruding end surface, and a discharge port 42 is provided at the upper part of the cylindrical side wall. is formed. An anode electrode 4 is provided on the inner wall of the plating chamber 4 at the opening edge of the jet nozzle 41.
4 is provided, which is connected to a power source 8 outside the chamber 4. Further, a conduit 75 from the three-way valve 72 is connected to the jet nozzle 41 .

A sill ring 4 is provided on the upper surface of the opening periphery of the plating chamber 4.
A pallet 1 (details of which will be described later) on which a wafer W is mounted is placed in pressure contact with the seal ring 43, and the pallet 1 is placed on a carrier 2 (
Figure 2).

The carrier 2 can be moved to the right half of the base 91 by a mechanism to be described later, and FIG. 1 actually shows one carrier 2 in a bad condition at the right end of movement. A wafer elevating mechanism 5, the details of which will be described later, is provided at this right moving end.

The detailed structures of the pallet 1 and carrier 2 will be explained below.

The pallet 1 has a rectangular substrate 11 (FIG. 3),
At the center of the substrate 11 is a substantially circular opening 12 with a portion straight.
is formed, and the upper surface of the edge of the opening 12 is counter-sunk with a constant width (FIG. 4), and the plate-shaped seal 13 is disposed flush with it. The shape of the opening 12 is along the wafer W and has a slightly smaller diameter than the wafer W, so that the lower surface of the wafer W, which is the surface to be plated, is exposed to the opening 12 as if the wafer W was placed thereon.

Clamp mechanisms 14 are provided on the substrate 11 at positions facing each other with the opening 12 in between, and each clamp mechanism 14 has a shaft 143 having a grip plate 141 fixed to its tip and biased to protrude by a coil spring 142. The shaft 143 is supported by a bracket 145 provided with a direct-acting bearing 146, and the rear end large diameter portion 144 of the shaft abuts against the bracket 145 and is positioned at the protruding end.

A power receiving contact 15 consisting of a bolt 151 and a washer 152 is provided at an opposing position 90 degrees apart from each of the clamp mechanisms 14 with the opening 12 in between. A cathode electrode 16 extending to the opening 12 is provided. This cathode electrode 16 is a very thin film (approximately 50 μm) and is adhered to the seal surface.

The carrier 2 has a rectangular frame 21 (FIG. 2) having a slightly larger diameter than the pallet 1, and a shaft 22 is supported on a pair of opposite sides of the frame 21 so as to be vertically movable by a linear bearing. ing. The shaft 22 is urged to the upper end position by a coil spring 23, and
A plate-shaped claw body 24 is fixed to the lower end of each shaft 2.
Two claw bodies 24 protrude into the frame 21 and receive stepped portions on the lower surface of the side edges of the pallet 1.

The lower surface of the opposite side of the frame 21 is a bracket 2
5 (FIG. 2) to the rodless cylinder 26 extending in the left-right direction on the base 91, and the other side is connected to the rodless cylinder 26 via the base 91 (FIG. 2).
The cylinder 26 is slidably connected to a guide shaft 27 disposed on the cylinder 26 in parallel with the cylinder 26. Thus, the carrier 2 is moved into the plating chamber 4 at the left end by the cylinder 26.
It is moved between a position directly above the wafer lifting mechanism 5 and a position directly above the wafer lifting mechanism 5 at the right end.

The elevating mechanism 5 has a circular receiving plate 53 fixed to the tip of a piston rod 52 that extends from a cylinder 51 (Fig. 1) and moves up and down. During the ascent, the wafer W placed on the pallet 1 is pushed up and taken out, and during the descent, the wafer W is placed on the pallet. In addition, supplying the wafer W to the raised pedestal 53,
The wafer W is then taken out by a robot arm 54 that operates in a swiveling manner. Further, the presence of the wafer W on the pedestal 53 is confirmed by the photoelectric switch 55.

Directly above the plating chamber 4, a pressing mechanism 3 is fixed to a pedestal 9, and a pressing machine'! f43 is a thick circular pressing plate 33 (see FIG. 2) provided at the tip of a piston rod 32 that extends from the cylinder 31 and moves up and down, and a support arm 34 provided along the upper surface of the suppressing plate 33. Rod-shaped power supply contacts 36 are provided at both ends of the pallet 1, which is biased downward by a coil spring 35 and can be moved up and down. and are connected to the power source 8, respectively.

Note that the operating ends of each of the cylinders 26, 31, and 51 are connected to position sensors 26a, 26b, 31a, 3lb, and 5, respectively.
1a, 5lb.

The operation of the plating device with the above structure will be explained below. The pallet 1 is placed on the claw body 24 on the carrier 2 located at the right end position, and each clamp mechanism 14 on the pallet is moved back as the shaft large diameter portion 144 is pulled by an unillustrated tension mechanism. In this state, the cradle 53 of the elevating mechanism 5 rises within the opening 1a of the pallet 1, receives the wafer W from the robot arm 54, and in the process of descending, the lower outer peripheral edge of the wafer W is placed on the seal 13 of the pallet 1. Place it on. The tension mechanism eliminates the tension in the large diameter portion 144 of the shaft, and
43 is advanced by the spring force of the coil spring 142, and the gripping plate 141 fixes the wafer W from both sides. Since a part of the outer periphery of the wafer W is a straight line, the wafer W rotates so as to fit into the grip plate 141 when fixed, and is accurately positioned.

The carrier 2 is moved to the left by the rodless cylinder 26 and reaches a position directly above the plating chamber 4.

Here, the rod 31 of the pressing mechanism 3 is lowered, and during the lowering, the power supply contact 36 contacts the power reception contact 15 on the pallet 1 and becomes conductive. The descending press plate 33 hits the top surface of the wafer W,
Pallet substrate 11 via the wafer W and seal 13
is pushed down against the supporting force of the claw body 24. As a result, the seal ring 4 of the chamber 4 is fitted onto the lower surface of the substrate 11.
3, the opening 1a coincides with the opening of the chamber 4, and at the same time, the lower surface of the wafer W, which is the surface to be plated, is in close contact with the seal 13.
The cathode electrode 16 on the seal 13 is electrically connected to the cathode electrode 16 on the seal 13.

When the three-way valve 72 is activated and the plating solution discharged from the pump 7 is supplied to the jet nozzle 41 through the pipe 75, the plating solution receives a positive charge from the anode electrode 44 and is ejected into the plating chamber 4, and the wafer W is A plating layer is formed on the bottom surface of the plate.

After the plating process is completed, when the pressing plate 33 is raised, the power feeding contact 36 and the power receiving contact 15 are separated and cut off, and the suppressing plate 3
3, the pallet 1 is pulled upward by the claw plate 24. The carrier 2 is moved back to the right end again, and after widening the gap between the gripping plates 141 by the side of the tensioning machine, the pedestal 53 of the lifting mechanism 5 rises and pushes up the inner peripheral part of the lower surface of the wafer W, lifting the wafer W. Take it out from the top of pallet 1.

According to this embodiment, if the shape of the wafer W is changed, it can be dealt with immediately by replacing the pallet 1, and there is no need to provide dedicated equipment for each wafer W, so equipment costs are reduced. In addition, the setup time for dealing with changes in the wafer W can also be significantly reduced.

Since the wafer W is taken out by being pushed up from below by the lifting mechanism 5 at a position away from the plating chamber 4, damage to the wafer can be effectively prevented.

Furthermore, since the cathode electrode 16, which requires periodic inspection, is provided on the pallet 1, there is no need to stop the entire apparatus when maintaining the electrode.

In the above embodiment, only one carrier 2 is used, but it is possible to provide a plurality of carriers 2 and move them sequentially onto the plating chamber 4, and to provide each carrier with a pallet 1 for wafers W having different diameters in advance. , it is possible to shorten the setup time when changing the wafer W. In this case, the pallet 1 does not necessarily need to be structured so that it can be easily separated from the carrier 2.

The structure of the plating chamber may be as shown in FIG. In the figure, a plating solution introduction pipe 46 is inserted into the plating chamber 4 from below, and a porous nozzle 45 is attached to the tip of the introduction pipe 46. The liquid tightness of the chamber 4 is ensured by a bellows 47 that connects the periphery of the through hole through which the introduction tube 46 is inserted and the tip of the introduction tube 46.
4, 485 and gears 481, 482, 483 approximately 9
It is forced to rotate back and forth between 0 degrees.

In this situation, the plating solution supplied into the introduction tube 46 passes through the through hole of the anode electrode 44 provided in the introduction tube 46, reaches the upper porous nozzle 45, and is ejected in a shower form.

[Effects of the Invention] As described above, the plating apparatus of the present invention can handle wafers of different diameters with the same equipment, and can also do so quickly, reducing equipment costs and improving work efficiency. This is a significant improvement.

Furthermore, since it is not necessary to take out the wafer on the plating chamber, it is possible to take out the wafer by pushing it up from below, thereby effectively preventing damage to the wafer.

[Brief explanation of drawings]

Figures 1 to 4 show an embodiment of the present invention, with Figure 1 being a cross-sectional overall side view of the main parts of the device, Figure 2 being a cutaway perspective view of the main parts of the device, and Figure 3 being a plan view of the pallet. , FIG. 4 is a sectional view taken along the line IV--IV in FIG. 3, FIG. 5 is a cutaway perspective view showing another example of the plating chamber, and FIG. 6 is a side view of the entire main part of the conventional device in cross section. 1... Pallet 1a... Opening 2... Carrier 3... Pressing mechanism (pressing means) 4... Plating chamber 5... Lifting mechanism 7... Pump 8... Power supply W...・Wafer Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A pallet on which a wafer is placed and has an opening for exposing the lower surface of the wafer to be plated in the placed state; a plating chamber that elastically supports the pallet and opens upward; and a plating chamber. A carrier moves between a more distant position and the wafer transferred by the carrier to a position directly above the plating chamber is pressed from above to plate the outer periphery of the lower surface of the wafer on the opening edge of the pallet and the lower outer periphery of the pallet. A plating device comprising pressing means for bringing each chamber opening edge into liquid-tight pressure contact.