JPH09306974A - Work holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work holder which can prevent oxidation of an entire surface of a work to be fed thereby in a non-contact condition. SOLUTION: The work holder for holding a work W in a non-contact condition comprises a plate-like member 12 made in its center with a fluid ejecting hole 13, a fluid supply pipe 14 connected to the ejecting hole 13 for ejecting an inactive gas from the ejecting hole 13 toward an underside of the plate member 12, thereby causing the plate member to hold the work W in a non- contact condition, and a guide 17 provided at a peripheral part of the plate member 12 for guiding the fluid ejected from the hole 13 and make to flow to the exterior from an upper surface peripheral part of the work into a lower surface side of the work W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work holding device for holding and carrying a work such as a semiconductor wafer in a non-contact state.

[0002]

2. Description of the Related Art When manufacturing a semiconductor device or a liquid crystal display device, a holding device is used to hold and convey a work such as a semiconductor wafer or a liquid crystal substrate between steps.
As a holding device, a means for holding and carrying the work in a contact state and a means for holding and carrying the work in a non-contact state by utilizing Bernoulli's principle are generally known, and dust is attached to the work. It is better to hold and convey the non-contact state from the viewpoints of preventing the above-mentioned work and preventing the above-mentioned work from being applied.

When manufacturing a semiconductor device or a liquid crystal display device, for example, the work is repeatedly subjected to a film forming process and an etching process, and the work is brushed between these processes. There is a first cleaning step for rough cleaning by means of a second cleaning step and a second cleaning step for spin cleaning the roughly cleaned work.

When the washed work is conveyed to the next step,
The surface of the work may be oxidized when it comes into contact with air, and in such a case, it is necessary to remove the oxide film. Therefore, it has been attempted to prevent the work from being oxidized by using an inert gas as the fluid ejected from the holding device in order to generate buoyancy in the work. However, since the fluid ejected from the holding device flows along the upper surface of the work and hardly turns to the lower surface side, the lower surface side of the work may come into contact with air and be oxidized. It was

Further, when the work that has undergone the film forming process or the etching process is conveyed to the cleaning process in a non-contact state by the holding device, a gas is blown to the work to generate buoyancy. Therefore, the surface of the washed work is partially dried by the flow of the gas.

If the surface of the work dries, the dust generated in the previous step may stick to the surface of the work, and the dust may not be reliably removed in the washing step. Especially, if the surface of the above work gets dried and dust sticks in the process of rough cleaning and then spin cleaning,
It may be difficult to remove the dust adhering to the work very much by the spin cleaning. Moreover, the drying of the work occurs not only on the upper surface side on which the gas is blown, but also on the lower surface side, so it is desirable to prevent the lower surface side from drying.

[0007]

As described above, Berne-
When a work is held and conveyed in a non-contact state by utilizing the principle of b., An inert gas is used to prevent oxidation of the work. Although it is possible to prevent oxidation on the upper surface side of the metal, the lower surface side may be oxidized.

Further, if the work is dried during the cleaning process, dust may stick to the surface of the work, so that the dust may not be properly cleaned and removed.

A first object of the present invention is to provide a work holding device which does not oxidize the entire surface of the work when the work is held and conveyed in a non-contact state. Especially.

A second object of the present invention is to provide a work holding device which can convey the work to a cleaning process without drying it and ensure the cleaning.

A third object of the present invention is to provide a work holding device capable of stabilizing the supporting state of the work by guiding the gas jetted to the upper surface side of the work to the lower surface side. To do.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention described in claim 1 is a work holding device for holding a work in a non-contact state, in which a fluid is provided in the central portion. Of the plate-shaped body having the ejection holes formed therein, and the inert gas is ejected from the ejection holes to the lower surface side of the plate-shaped body so that the work is not in contact with the lower surface side. Fluid supply means for holding the same in a state and an inert gas, which is provided in the peripheral portion of the plate-like body and is ejected from the ejection hole and flows outward from the peripheral portion of the upper surface of the work, to the lower surface side of the work. It is characterized by comprising a guide portion for guiding.

According to a second aspect of the present invention, in a work holding device for holding a work in a non-contact state, a plate-shaped body having a fluid ejection hole formed in a central portion thereof, Fluid supply means connected to the ejection hole for ejecting a humidifying body from the ejection hole to the lower surface side of the plate-like body to hold the work in a non-contact state on the lower surface side. To do.

According to a third aspect of the present invention, in the second aspect of the invention, the peripheral portion of the plate-like body is jetted from the jet holes and flows outward from the peripheral portion of the upper surface of the work. A guide portion for guiding the humidified air to the lower surface side of the work is provided.

According to a fourth aspect of the present invention, in a work holding device for holding a work in a non-contact state, a plate-shaped body having a fluid ejection hole formed in a central portion thereof, Fluid supply means connected to the ejection hole for ejecting gas from the ejection hole to the lower surface side of the plate-like body to hold the work in a non-contact state on the lower surface side, and a peripheral portion of the plate-like body. And a guide portion for guiding the gas, which is ejected from the ejection hole and flows outward from the peripheral portion of the upper surface of the work, to the lower surface side of the work.

According to the first aspect of the invention, in the work held in the non-contact state, the inert gas ejected on the upper surface side is guided by the guide body and flows also on the lower surface side. It is possible to prevent the upper and lower surfaces of the work from being oxidized.

According to the second aspect of the present invention, the work held in the non-contact state is prevented from being dried and dust sticks to the work by the humidifying body being jetted to the upper surface side thereof. It can be prevented.

According to the invention of claim 3, not only the upper surface side of the work but also the lower surface side can be prevented from being dried and dust can be prevented from adhering thereto. According to the invention of claim 4, the gas flowing out from the guide portion covers almost the entire lower surface side of the work, so that the holding state of the work is not easily affected by the disturbance.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. 2 and 3 show a part of a manufacturing process of a liquid crystal display device or a semiconductor device, in which 1 is a brush cleaning process as a first cleaning process and 2 is a spin cleaning process as a second cleaning process. Is.

The brush cleaning step 1 is composed of a lower brush 3 and an upper brush 4 which are vertically opposed to each other at a predetermined interval and are rotationally driven in a direction of an arrow by a drive source (not shown). A cleaning liquid (not shown) is supplied between the pair of brushes 3 and 4, and a work W such as a liquid crystal substrate or a semiconductor wafer conveyed by the first conveyor belt 5 is conveyed. As a result, the upper and lower surfaces of the work W are cleaned by the brushes 3 and 4.

The work W cleaned in the brush cleaning step 1 is sent out onto the second conveyor belt 6. The work W sent onto the conveyor belt 6 is held by the first holding device 7A and supplied to the spin cleaning step 2. The spin cleaning step 2 has a housing 8, and the housing 8 has a spin chuck 9 rotatably driven while holding the work W and a cleaning liquid in the work W held by the spin chuck 9. A nozzle body 10 for supplying the water is rotatably provided.

When the work W is supplied to the spin chuck 9, the nozzle body 10 is rotated, and the tip of the nozzle body 10 is rotated.
Located above the central portion of the workpiece W, the cleaning liquid is ejected toward the workpiece W, and the spin chuck 9 is rotationally driven. As a result, the work W is spin-washed.

The spin-washed work W is taken out of the spin chuck 9 by the second holding device 7B,
It will be transported to the next step. The first and second holding devices 7A and 7B are reciprocally driven within a predetermined range by the arm 11. That is, one end of the arm 11 is rotationally driven and vertically driven by the drive source 12, and the other end is provided with the first and second holding devices 7A and 7B.

Each of the holding devices 7A and 7B has a plate-like body 12 having a circular plane as shown in FIG. An ejection hole 13 is formed in the center of the plate-shaped body 12, and one end of a supply pipe 14 is connected to the ejection hole 13, and the plate-shaped body 12 is connected through the supply pipe 14. Mu 11
Is attached to the other end of.

The outer peripheral member of the plate-shaped body 12 is provided with an outer curl member 15 curved in an arc shape toward the lower surface thereof, and the inner curl member 15 has an outer curl member on the inner surface thereof. An inner curling member 16 which is also bent in an arc shape is provided so as to face the inner surface of the curling member 15 at a predetermined interval.
As a result, the work W, in which the fluid ejected from the supply pipe 14 by the outer curling member 15 and the inner curling member 16 is held by the plate-like body 12 by the Bernoulli's principle, as described later. A guide portion 17 for guiding the lower surface side of the.

The inner curling member 16 is supported on the peripheral portion of the lower surface of the plate member 12 by a plurality of supporting members 18 which are vertically provided at predetermined intervals in the circumferential direction. As shown in FIG. 3, the supply pipe 14 of the first holding and conveying device 7A is
For example, the supply pipe 14 of the second holding device 7B is connected to the first supply source 21 that stores humidified air in which the above is mixed with air in a predetermined ratio, and the second supply source 22 that stores the humidified air. It is connected to the.

Next, the operation of the apparatus having the above configuration will be described. Brush cleaning step 1 using the first conveyor belt 5
The upper and lower surfaces of the work W supplied to the cleaning unit 1 are cleaned by the pair of brushes 3 and 4, and are discharged from the brush cleaning step 1 by the second conveyor belt 5.

When the work W is carried out to a predetermined position, the second carry-out belt 5 is stopped, and the arm 11 to which the first holding device 7A is attached is driven in the rotating direction, The first holding device 7A is positioned above the work W. Next, the first holding device 7A is driven in the descending direction and positioned so that the lower surface of the plate-shaped body 12 faces the upper surface of the work W at a predetermined interval. In this state, when the humidified air supplied from the supply pipe 14 is ejected from the ejection holes 13 at a predetermined pressure, the humidified air flows from the central portion of the upper surface of the work W toward the peripheral portion thereof. The work W floats according to the principle of (3) and is held in the plate-like body 12 in a non-contact state.

When the first holding device 7A holds the work W, the arm 11 ascends and is then driven to rotate above the spin chuck 9 in the spin cleaning step 2 and then to move in the descending direction. The work W is positioned on the upper surface of the spin chuck 9 at a slight interval. In this state, the supply of humidified air is stopped, so that the work W is transferred onto the upper surface of the spin chuck 9.

While the work W is transferred from the brush cleaning process 1 to the spin cleaning process 2, the work W is floated and held by the Bernoulli principle from the ejection hole 13 of the first holding device 7A. Humidified air is ejected as a fluid for the operation. The humidified air flows from the center of the upper surface of the work W to the peripheral portion, and when flowing out from the peripheral portion to the outside, the guide portion 17
And flows out at an angle slightly inclined to the lower surface of the work W rather than parallel. In other words, work W
An air curtain for humidified air is formed on the lower surface side of the.

Therefore, the work W is the brush cleaning step 1
During the transfer from the spin cleaning step 2 to the spin cleaning step 2, the humid state is maintained by the humidified air flowing along the upper and lower surfaces thereof, so that dust remaining on the surface of the work W is prevented from sticking. Therefore, in the spin cleaning step, since the surface of the work is in a wet state, the surface can be cleaned well.

When the work W has been spin-cleaned in the spin-cleaning step 2, the second holding device 7B is rotationally driven upward and then downwardly driven to the upper surface of the work W. It is positioned at a predetermined interval. In that state, the second
Since the inert gas is ejected from the ejection holes 14 of the holding device 7B, the work W is sucked and held in a non-contact state by the flow of the inert gas.

Then, the second holding mechanism 7B is driven in the ascending direction and then in the rotating direction to be positioned above the next step (not shown) such as the film forming step. Work W taken out from spin cleaning step 2
Is transferred to the next step, the ejection hole 1 of the holding mechanism 7B is transferred.
An inert gas is ejected from 3 as a fluid for sucking and holding the work W. The inert gas flows not only from the upper surface of the work W but also from the guide portion 17 to the lower surface side, and forms an inert gas air-caten on the lower surface side.

Therefore, the spin-washed work W is covered with an inert gas on almost the entire surface thereof, so that the work W is prevented from being oxidized by contact with air. In the first and second holding devices 7A, 7B, the work W held with the upper surface facing the lower surface side of the plate-like body 12 has humidified air or an inert gas flowing from the guide portion 17 on the lower surface side. Are covered by each. That is, the air curtain is formed on the lower surface side of the work W. Therefore, the work
Since the outside air is hard to act on the lower surface of the work W, the holding state of the work W is less susceptible to the influence of disturbance. In other words, work W
Can be held in a stable state.

The present invention is not limited to the above embodiment,
Various modifications can be made without departing from the spirit of the invention. For example, the first holding device and the second holding device may be used in a process other than the brush cleaning process and the spin cleaning process, that is, the process in which the wet state of the work needs to be maintained, Any process that prevents oxidation can be applied. Further, although the guide portion is formed over the entire outer periphery of the plate-shaped body, it may be partially provided at predetermined intervals in the circumferential direction.

[0036]

As described above, according to the invention of claim 1, an inert gas is used as a fluid for holding the work in a non-contact state on the lower surface side of the plate-like body. Since it can be flowed not only on the upper surface side of the work but also on the lower surface side, it is possible to prevent the upper and lower surfaces of the work from being oxidized.

According to the second aspect of the invention, humidified air is used as a fluid for holding the work in a non-contact state on the lower surface side of the plate-like body, and the humidified air is caused to flow to the upper surface side of the work. Thus, the wet condition was maintained.

Therefore, for example, when the work is washed once and then washed for the second time, it is possible to prevent the dust remaining in the first wash from sticking to the work, so that the second wash is performed. Can be surely removed by.

According to the third aspect of the present invention, since the humidified air is made to flow not only on the upper surface side of the work but also on the lower surface side, dust sticks to the upper and lower surfaces of the work due to drying. Can be prevented.

Further, according to the invention of claim 4, since the lower surface of the work is covered with the fluid flowing out from the guide portion, the work is less affected by the outside air, so that the holding state is stabilized. Can be made.

[Brief description of drawings]

FIG. 1 is a sectional view of a holding device showing an embodiment of the present invention.

FIG. 2 is a plan view of a cleaning process in which the holding device is also used.

FIG. 3 is a side view of a cleaning process in which the holding device is also used.

[Explanation of symbols]

12 ... Plate-shaped body, 13 ... Jet holes, 14 ... Supply pipe (fluid supply means), 17 ... Guide part, 21, 22 ... Fluid supply source (fluid supply means), W ... Work.

Claims (4)

[Claims] 1. A work holding device for holding a work piece in a non-contact state, comprising: a plate-shaped body having a fluid ejection hole at a central portion thereof; and a ejection hole connected to the ejection hole. Fluid supplying means for holding the work in a non-contact state on the lower surface side by ejecting an inert gas to the lower surface side of the plate body from the above, and the ejection holes provided in the peripheral portion of the plate body. A work holding device comprising: a guide portion that guides an inert gas, which is ejected from the work and flows outward from a peripheral portion of the upper surface of the work, to the lower surface side of the work. 2. A work holding device for holding a work piece in a non-contact state, comprising: a plate-shaped body having a fluid ejection hole formed in a central portion thereof; and a ejection hole connected to the ejection hole. The humidifying body is ejected from the plate-shaped body to the lower surface side of the plate-shaped body, and
A work holding device comprising a fluid supply means for holding the work in a non-contact state. 3. A guide portion is provided in the peripheral portion of the plate-like member for guiding the humidified air, which is ejected from the ejection hole and flows outward from the peripheral portion of the upper surface of the work, to the lower surface side of the work. The work holding device according to claim 2, wherein the work holding device is provided. 4. A work holding device for holding a work piece in a non-contact state, comprising: a plate-shaped body having a fluid ejection hole formed in a central portion thereof; and a ejection hole connected to the ejection hole. To the lower surface side of the plate-like body, a fluid supply means for holding the work in a non-contact state on the lower surface side of the plate-like body; And a guide portion for guiding the gas flowing outward from the peripheral portion of the upper surface of the work to the lower surface side of the work, the work holding device.