JP4265306B2 - Wafer delivery device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wafer delivery apparatus, and more particularly to a wafer delivery apparatus that is used in a chemical mechanical polishing (CMP) apparatus and the like, receives a wafer from a transfer means, and passes the received wafer to another transfer means.
[0002]
[Prior art]
In recent years, with the development of semiconductor technology, the miniaturization of design rules and the increase in the number of multilayer wirings have progressed, and the wafer diameter has been increased in order to reduce costs. Therefore, when trying to form the pattern of the next layer as it is on the layer where the pattern is formed as in the past, it is difficult to form a good pattern in the next layer due to the unevenness of the previous layer, It was easy to occur.
[0003]
Therefore, the surface of the layer on which the pattern is formed is flattened, and then the pattern of the next layer is formed. In this case, a wafer polishing apparatus using a CMP method is used.
[0004]
As a wafer polishing apparatus by this CMP method, a disk-shaped polishing surface plate having a polishing pad affixed to the surface, and a wafer carrier that holds one surface of the wafer and makes the other surface of the wafer contact the polishing pad A CMP apparatus that polishes the other surface of the wafer while rotating the polishing platen and bringing the wafer into contact with the polishing pad while rotating the wafer carrier and supplying a slurry as an abrasive between the polishing pad and the wafer. Generally known widely.
[0005]
A plurality of transfer devices for transferring a wafer are incorporated in the CMP apparatus, and the wafer is transferred to each part of the CMP apparatus by the plurality of transfer apparatuses and polished to flatten the surface. In addition, a wafer delivery stage is incorporated for delivering a wafer between one transfer device and another transfer device.
[0006]
The wafer delivery stage is a stage having a concave portion slightly larger than the diameter of the wafer and provided with a water supply port on the bottom surface of the concave portion. When receiving the wafer from the transfer device, the concave portion is received on the bottom surface of the concave portion. A load stage has been proposed in which positioning is performed on the side of the wafer and water is supplied to the recess when the wafer is transferred to another transfer device, and the wafer is floated and lifted (see, for example, Patent Document 1).
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-124174
[Problems to be solved by the invention]
However, in the case of wet processing using a slurry such as a CMP apparatus, when the polished wafer is transferred from the wafer carrier of the polishing head, the wafer may fall off obliquely without being uniformly peeled from the wafer carrier. In such a case, in the wafer delivery stage described in Patent Document 1, the edge of the wafer may collide with the bottom surface of the delivery stage and damage the edge portion.
[0009]
In addition, since the wafer falls obliquely, the wafer rides on the side surface of the concave portion of the stage, and the wafer may not be positioned. Further, when the wafer is transferred to another transfer device, there is a problem that the wafer is not easily peeled off from the surface of the liquid and cannot be transferred smoothly.
[0010]
Also, when draining the liquid that floats the wafer in the wafer delivery stage, the diameter of the drain port provided on the stage cannot be increased due to the miniaturization of the stage, and draining takes time. It took a lot of time to deliver the wafer. Also, when draining from a small-diameter drain in a short time, a method of connecting a vacuum pump to the drain pipe is also known, but this method has a disadvantage that it is large as a draining means and is expensive. .
[0011]
For this reason, it has been very difficult to realize a transfer system that stably delivers a polished wafer in a short time.
[0012]
The present invention has been made in view of such circumstances, and when a wafer is received from a transfer means, even a wet-processed wafer can be easily received in a state where the impact is kept low. It is an object of the present invention to provide a wafer transfer device that can easily peel off a wafer in a short time when it is transferred to a transfer means and can be transferred stably to a transfer device.
[0013]
[Means for solving the problems]
The c Eha receive from the first conveying means, the wafer transfer device that passes a wafer received to the second conveying means, and transfer stage capable of storing the liquid therein, liquid supply means for supplying liquid into the receiving pass stage If has a drainage unit that issues discharge the liquid in the transfer stage, is provided in the delivery in stage, and a support member for supporting the wafer when the liquid in the transfer stage is discharged, said effluent The means includes a sealed container in which liquid is stored in advance, a drain pipe provided at a lower part of the delivery stage, a first valve connected to the drain pipe and provided at an upper part of the sealed container, and the sealed container wherein c comprises between large second valve aperture than the first valve provided at the lower portion, and a large drain port of diameter than the said second valve is provided first valve When receiving the Doha from said first conveying means receives the wafer in the liquid surface of the liquid, when passing the wafer to the second conveying means, said second valve while opening the first valve The liquid stored in the sealed container is discharged from the drainage port and the inside of the sealed container is depressurized to discharge the liquid in the delivery stage into the sealed container. It is characterized by passing in a state of being supported by the support member.
[0014]
According to the first aspect of the present invention, when the wafer is received, it is received at the liquid level. When the wafer is transferred, the liquid is rapidly discharged to eliminate the influence of the surface tension of the liquid, so that the wafer can be transferred stably in a short time. .
[0020]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a wafer delivery apparatus according to the present invention will be described in detail below with reference to the accompanying drawings. In addition, in each figure, the same number or the code | symbol is attached | subjected about the same member.
[0021]
1 and 2 are conceptual diagrams showing an embodiment of a wafer delivery apparatus. FIG. 1 shows a state in which a wafer is received from a first transfer means, and FIG. 2 shows a state in which the wafer is delivered to a second transfer means. It represents.
[0022]
The wafer delivery apparatus 10 includes a delivery stage 11 capable of storing a liquid therein, a plurality of support members 12, 12,... Provided in the delivery stage 11, pure water 13 that is a liquid stored in the delivery stage 11, and A pure water supply source 15 which is a liquid supply means for supplying pure water 13 into the delivery stage 11 via the water supply pipe 14A, and a sealed container for rapidly draining the pure water 13 within the delivery stage 11 via the drain pipe ( (Rapid draining means) 16 and the like.
[0023]
The delivery stage 11 has a circular recess, and the inner diameter of the recess is slightly larger than the outer diameter of the wafer W to be delivered, and the wafer W is centered here.
[0024]
The pure water supply source 15 includes a pure water production apparatus, a pure water tank, a supply pump, and the like (not shown). The pure water supply source 15 is connected to the water supply pipe 14A of the delivery stage 11 through a solenoid valve 15A through a water supply tube 15B. Pure water 13 is supplied to the recess.
[0025]
Six support members 12, 12,... Provided at the bottom of the recess of the delivery stage 11 are arranged at equal intervals on the circumference and protrude from the bottom by 2 to 3 mm. The pure water 13 stored in the delivery stage 11 is preferably poured to a depth at which the tips of the support members 12, 12,.
[0026]
Sufficient pure water 13 is stored in advance in a sealed container 16 serving as a quick drain means. The sealed container 16 has a large-diameter drainage port 16D formed at the bottom, and a large-diameter drainage port 16D is provided with a large-diameter solenoid valve 16A, which is a large-diameter drain valve, and is stored inside. The purified pure water 13 can be drained rapidly.
[0027]
The sealed container 16 is connected to the drain pipe 14B of the delivery stage 11 by a drain tube 16C via a solenoid valve 16B attached to the upper surface, and the pure water 13 stored in the recess of the delivery stage 11 is passed through the sealed container 16 inside. It can be drained.
[0028]
Since the sealed container 16 is connected to the delivery stage 11 by the drain tube 16C, it is not always necessary to place the sealed container 16 in the immediate vicinity of the delivery stage 11, and it may be installed in a place with sufficient space. Therefore, even if the delivery stage 11 is provided in a narrow space, it can be easily connected.
[0029]
Next, the operation of the wafer delivery apparatus 10 configured as described above will be described. When the wafer W is first received from the wafer carrier 31 of the polishing head as the first transfer device, as shown in FIG. 1, first, the electromagnetic valve 16B of the hermetic container 16 is closed, and then pure water supply as a liquid supply means is provided. The electromagnetic valve 15A provided in the source 15 is opened, and the delivery stage 11 is on standby with the pure water 13 being poured into the above-described depth by the pure water supply source 15.
[0030]
Next, the wafer carrier 31 adsorbing the processed wafer W moves to above the delivery stage 11 and descends to near the liquid surface of the pure water 13, and then the adsorption of the wafer W is released. Even if the wafer W is tilted and dropped from the wafer carrier 31 without being evenly separated, the wafer W is landed on the liquid surface of the pure water 13 with a low impact (hereinafter referred to as soft landing), and a delivery stage. 11 is held in the centered state in the recess.
[0031]
Next, when the wafer W is transferred from the wafer transfer apparatus 10 to the second transfer means 41, as shown in FIG. 2, the electromagnetic valve 16B of the sealed container 16 is opened and the large-diameter electromagnetic valve 16A is opened. When the large-diameter solenoid valve 16A is opened, the pure water 13 stored in the sealed container 16 is rapidly drained to the outside from the large-diameter drain port 16D. Then, since the inside of the sealed container 16 is in a reduced pressure state, the pure water 13 stored in the delivery stage 11 rapidly flows into the sealed container 16 and the pure water 13 in the delivery stage 11 is completely drained.
[0032]
When the pure water 13 in the sealed container 16 is drained by the same amount as that of the pure water 13 stored in the delivery stage 11, the large-diameter solenoid valve 16A is closed. Thereby, even if the above-described operation is repeated, a predetermined amount of pure water 13 is always stored in the sealed container 16.
[0033]
As described above, when the pure water 13 in the delivery stage 11 is drained, the wafer W is supported by the support members 12, 12,. In this state, the suction head 41A of the second transfer means 41 is lowered to suck and transfer the wafer W. At this time, since the contact area between the tips of the support members 12, 12,... And the wafer W is very small, even if the wafer W is wet, the influence of the surface tension can be ignored and the wafer W can be easily transferred. .
[0034]
As described above, when the wafer W is received from the wafer carrier 31 of the polishing head which is the first transfer means, the wafer W is softly landed on the surface of the pure water 13 stored in the delivery stage 11 and the impact is suppressed. You can receive it.
[0035]
Further, when the wafer W is transferred from the wafer transfer apparatus 10 to the second transfer means 41, the pure water 13 stored in the transfer stage 11 is rapidly drained by the sealed container 16 which is a quick drain means, and the wafer W is discharged. Are supported in a state of being supported by the support members 12, 12,..., The influence of the surface tension of the pure water 13 is eliminated, and the wafer W can be easily delivered.
[0036]
In the above-described embodiment, pure water 13 is used as the liquid. However, the present invention is not limited to this, and various liquids can be used as long as they do not contaminate the surface to be processed or cause a chemical reaction. is there.
[0037]
Further, when the wafer W is transferred from the wafer transfer apparatus 10 to the second transfer means 41, the pure water 13 stored in the transfer stage 11 is completely drained, but the wafer W and the pure water are not drained completely. You may make it drain to the water level from which the contact with 13 is cut | disconnected or a contact area reduces.
[0038]
【The invention's effect】
As described above, according to the present invention, when the wafer is received from the transfer means to the wafer delivery device, the wafer is received at the liquid level. However, it can be easily placed on the wafer delivery device with the impact kept low.
[0039]
Also, when the wafer is transferred from the wafer transfer device to the transfer means, the liquid stored in the transfer stage of the wafer transfer device is quickly discharged to cut off the contact between the liquid and the wafer or reduce the contact area. Since the wafer is transferred in a state in which it is easily peeled off from the mounting surface, the wafer can be stably transferred to the transfer means in a short time.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a state of receiving a wafer in a wafer delivery apparatus according to an embodiment of the present invention. FIG. 2 is a conceptual diagram showing a state of delivering a wafer in the wafer delivery apparatus according to an embodiment of the invention. Explanation of]
DESCRIPTION OF SYMBOLS 10 ... Wafer delivery apparatus, 11 ... Delivery stage, 12 ... Support member, 13 ... Pure water (liquid), 14B ... Drain pipe, 15 ... Pure water supply source (liquid supply means), 16 ... Sealed container (rapid drainage means) ), 16A ... Large-diameter solenoid valve (large-diameter drain valve), 16D ... Large-diameter drain port, 31 ... Wafer carrier (first transfer means), 41 ... Second transfer means, W ... Wafer

Claims (1)

In a wafer transfer apparatus that receives a wafer from a first transfer means and passes the received wafer to a second transfer means,
A delivery stage capable of storing liquid inside;
Liquid supply means for supplying liquid into the delivery stage;
And drainage means that issues discharge the liquid in the transfer stage,
A support member that is provided in the delivery stage and supports the wafer when the liquid in the delivery stage is discharged;
The drainage means is
A sealed container in which liquid is stored in advance;
A drain pipe provided at a lower portion of the delivery stage;
A first valve connected to the drain pipe and provided at the top of the sealed container;
A second valve provided at a lower portion of the sealed container and having a larger diameter than the first valve;
When receiving the wafer and a large drain port of diameter than the said second valve is provided first valve from said first conveying means receives the wafer in the liquid surface of the liquid,
When passing the wafer to the second transfer means, the first valve is opened and the second valve is opened, and the liquid previously stored in the sealed container is discharged from the drain port. Then, the inside of the sealed container is decompressed to discharge the liquid in the delivery stage into the sealed container, and the wafer is delivered in a state of being supported by the support member.

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