JP2001063822A - Levitation conveying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To convey a plate-like body in no contact with a conveyance plane by arranging the plate-like body at least partially having a convexly curved surface on the conveyance plane with a convex surface faced to the conveyance plane, and floating and moving the plate-like body with the blowout of levitation air from the conveyance plane. SOLUTION: For conveying the plate-like body including curves and irregularities and at least partially having a convexly curved surface, e.g. a wafer 1, the wafer 1 is arranged on the conveyance plane 11 of a conveyance path 10 so that the convex surface 1A of the wafer 1 is faced to the conveyance plane 11. A jet quantity of the levitation air required for floating the wafer 1 from the conveyance plane 11 is spouted from the conveyance plane 11. The levitation air hits the convex surface 1A of the wafer 1 to float the wafer 1 then is lifted along the convex surface 1A, therefore the curved wafer 1 can be floated and conveyed along the conveyance plane 11 reliably in no contact with the conveyance plane 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a levitation transport method, and more particularly to a levitation transport method for transporting a plate in a non-contact state.

[0002]

2. Description of the Related Art In a floating transfer method, a plate-shaped body such as a semiconductor wafer or a glass plate for a display is floated from a transfer surface. That is, the levitation transport method transports the plate-like body without contacting the transport surface. There are various methods for floating the plate. One of them is a method in which a plate-like body is levitated by jetting gas.

In the floating transfer method using gas ejection, for example, as shown in FIG. 11, the wafer 201 is transferred to the processing apparatuses 101 and 102 in a non-contact manner for processing the wafer 201 as a plate. The processing apparatuses 101 and 102 are used for the wafer 2
01 is subjected to processing such as heating and film formation.

[0004] The processing apparatuses 101 and 102 include a transport path 111.
Through 113. Transport paths 111 to 11
3 ejects gas from those transport surfaces 111A to 113A. From the transfer surfaces 111A to 113A, a floating gas and a transfer gas are ejected. The gas for floating raises the wafer 201, and the gas for transfer is the transfer surfaces 111A to 111A.
In the longitudinal direction of 113A, that is, in FIG.
Then, the wafer 201 is transferred.

FIG. 12 shows the state of such gas ejection. As shown in FIG. 12A, the floating gas is ejected from the transport surface 111A of the transport path 111. At this time, the levitation gas moves upward from the transport surface 111A.
And it is ejected in a direction perpendicular to the transport surface 111A.
That is, the floating gas is ejected from the transfer surface 111A in the ejection direction 2.
Squirted into 12.

[0006] As shown in FIG. 12B, the transfer gas is transferred to the transfer surface 1 of the transfer path 111 in the same manner as the floating gas.
It is ejected from 11A. At this time, the transport gas is inclined toward the transport direction 211 so that the transport surface 111A is inclined.
It is ejected upward from. That is, the carrier gas is ejected from the transport surface 111A in the ejection direction 213.

The wafer 201 is transferred in a non-contact manner by the transfer gas and the floating gas. Then, the transferred wafer 201 is processed by the processing apparatuses 101 and 102, and thereafter, chips are cut out from the wafer 201.
The cut chips are mounted on various devices.

By the way, as the control of the device on which the chip is mounted becomes complicated and the device becomes thinner,
The wafer needs to be large and thin. Further, as the size of the display increases, the size of the glass plate needs to be increased. In this way, the large and thin plate-like body is also transported by the floating transport method.

[0009]

The size of a plate such as a wafer or a glass plate becomes large, and the thickness of the plate becomes 5 mm.
When the thickness becomes very thin, such as 0 to 100 [μm], the following problems occur in the floating conveyance method. That is, when the shape of the plate is small and the thickness is large, the plate is hard to bend. However, when the thickness of the plate-like body is small and the shape thereof is large, the plate-like body is easily bent.

When the plate-like body is easily bent, if the plate-like body is subjected to a process of providing a pattern or a film on one surface or a heating process, the plate-like body is warped. The plate-like body is curved. If the plate-like body is levitated and transported in a curved state to perform another process, the plate-like body may come into contact with the transport surface. Further, the wafer may stop on the transfer surface due to the contact between the plate and the transfer surface.

An object of the present invention is to solve such a problem and to provide a levitation transport method for preventing a curved plate from coming into contact with a transport surface when the plate is floated and transported. It is in.

[0012]

According to a first aspect of the present invention, there is provided an image forming apparatus, wherein at least a portion of the plate-like body having a convexly curved surface faces the conveying surface. Is disposed with respect to the transport surface, and the plate-like body is floated from the transport surface, and is moved along the transport surface.

According to the second aspect of the present invention, the first aspect is provided.
In the invention, in place of the plate-like body, a plate-like body including a convex part larger than the undulation in a surface having undulations, such that the convex part of the plate-like body faces a transfer surface, It is preferable to dispose it on the transport surface.

According to the invention described in claim 3, claim 1 is
Alternatively, in the invention according to the second aspect, it is preferable that a gas is ejected from the transport surface to float and transport the plate-like body.

[0015]

Next, an embodiment of the present invention will be described.

In this embodiment, the shape of a plate-like body such as a wafer or a glass plate is large, and the thickness of the plate-like body is 5 mm.
When the thickness becomes extremely thin, such as 0 to 100 [μm], the plate-like body is easily deformed. When various processes are performed on such a plate, for example, a process of providing a pattern or a film on one surface of the plate or a process of heating the plate, the plate is bent. Then, the cross-sectional shape of the plate-like body becomes like an arc or a semi-ellipse. Further, the plate-like body may be deformed, and undulation may be generated on the plate-like body, and may have a convex portion having a shape larger than that of the generated undulation.

In this embodiment, a plate-like body having a curve or undulation is transported by the following method. For example, when the plate-like body is a wafer, as shown in FIG. That is, when the wafer 1 is curved, at least a part of the wafer 1 has a convex curved surface. In FIG.
One whole surface of the wafer 1 is a convex surface 1A, and the other whole surface is a concave surface 1B. At this time, the wafer 1 is arranged on the transfer surface 11 so that the convex surface 1A of the wafer 1 faces the transfer surface 11 of the transfer path 10. In FIG. 1, FIG.
As in (A), the ejection direction of the floating gas is indicated by an arrow. Although not shown, the wafer 1 is fed by a carrier gas, as in FIG. 12B.

The wafer 1 placed in this manner has a convex surface 1A.
, And the top of the convex surface 1 </ b> A comes closest to the transfer surface 11. And
As for the gas for floating from the transfer surface 11, the convex surface 1 </ b> A
The wafer 1 disposed opposite to the above is ejected from the transfer surface 11 with an ejection amount necessary for floating the wafer 1 from the transfer surface 11. At this time, since the convex surface 1A of the wafer 1 is disposed so as to face the transfer surface 11 of the transfer path 10, the floating gas ejected from the transfer surface 11 hits the convex surface 1A to float the wafer 1, and then the convex surface It rises along 1A.

On the other hand, with respect to the transport surface 11 of the transport path 10,
When the wafer 1 is placed in a state opposite to the state shown in FIG.
Is as shown in FIG. With this arrangement, the floating gas ejected from the transfer surface 11 enters the concave surface 1B of the wafer 1 and moves along the concave surface 1B of the wafer 1 as shown in the flow direction 91. As a result, the gas moving along the flow direction 91 disturbs the flow of the floating gas ejected from the transport surface 11.
Further, since the warpage of the wafer 1 is not completely symmetric, the balance of the wafer 1 is disturbed, and the posture of the wafer 1 is inclined. In this state, in order to maintain the floating state of the wafer 1, if the amount of gas ejected is increased, the peripheral portion 1C of the wafer 1 and the convex surface 1A
The surface portion surrounding the concave surface 1B, that is, the surface portion surrounding the peripheral portion 1C, is brought into a wavy state by the ejection of the floating gas or the gas from the flow direction 91.

As described above, due to the inclination of the wafer 1, the waving state of the peripheral portion 1 C of the wafer 1, and the weak floating force, a part of the peripheral portion 1 C comes into contact with the transfer surface 11 as shown in FIG. Then, the wafer 1 stops on the transfer surface 11. In particular, as shown in FIG. 4, when the cross-sectional shape of the wafer 2 is an asymmetric bow, it becomes difficult for the wafer 2 to float from the transfer surface 11. The inventor of the present invention has found a method of transporting the wafer 1 as shown in FIG.

According to this embodiment, even if the wafer 1 being transferred in the state of FIG. 1 is tilted, the wafer 1 can be floated from the transfer surface 11 as shown in FIG. In addition, in this case, the levitation force is reduced at the peripheral portion 1C of the wafer 1 farthest in the direction perpendicular to the transfer surface 11, so that the peripheral portion 1C moves so as to rotate toward the transfer surface 11. As a result, the posture of the wafer 1 is automatically corrected in the direction indicated by the arrow 92. That is, an automatic correction action for correcting the posture acts on the wafer 1. Thereby, the wafer 1 is finally transferred in the posture of FIG. In addition, even when the wafer is curved as shown in FIG. 4, the wafer 2 is automatically corrected and transferred in a balanced state as shown in FIG.

As described above, according to this embodiment, even if the wafers 1 and 2 are curved, the convex surfaces 1
Since the wafer 1 is arranged so that A and 2A face the transfer surface 11 of the transfer path 10, the wafers 1 and 2 can be transferred while preventing the curved wafers 1 and 2 from contacting the transfer surface 11. it can.

According to this embodiment, the following wafer can be transferred in a non-contact manner. That is, in the wafer 3 shown in FIG. 7, one surface is convex, and
The convex surface 3A, which is one surface, is substantially symmetric, and the other surface 3B is unevenly undulated. Then, the wafer 3 is arranged so that the convex surface 3A faces the transfer surface 11 of the transfer path 10, and a sufficient amount of levitation gas is ejected from the transfer surface 11 to cause the wafer 3 to float.

In the wafer 4 shown in FIG. 8, one surface is convex, the convex surface 4A, which is one surface, is asymmetric, and the other surface 4B is uneven. And
The wafer 4 is arranged so that the convex surface 4A faces the transfer surface 11 of the transfer path 10, and a sufficient amount of levitation gas is ejected from the transfer surface 11 to float the wafer 4.

In the wafers 5 and 6 shown in FIGS. 9 and 10, undulations occur on both surfaces, and one surface has convex portions 5A and 6A larger than the undulations. Then, the wafers 5 and 6 are arranged so that the convex portions 5A and 6A face the transfer surface 11 of the transfer path 10, and a sufficient amount of levitation gas is ejected from the transfer surface 11 to float the wafers 5 and 6. I do.

The thus deformed wafers 3 to 6 can be transferred without contact with the transfer surface 11 of the transfer path 10.

Since a device for transporting the curved or deformed wafers 1 to 6 in a non-contact manner is not required, the transport path 1 is used for floatingly transporting the curved or deformed wafers 1 to 6.
It is possible to eliminate the need for exchanging 0 or the transfer surface 11. In addition, only by adjusting the ejection amount of the floating gas, the wafer 1
The wafers 1 to 6 can be reliably levitated in accordance with the curved state or the deformed state of the wafers 1 to 6.

In this embodiment, the wafers 1 to 6 are used as the plate-like members, but the present invention can be similarly applied to a plate-like member such as a glass plate.

Further, in this embodiment, the plate-like body is levitated and conveyed by jetting gas. However, the present invention is also applicable to levitating and conveyed by static electricity or ultrasonic waves.

[0030]

As described above, according to the first aspect of the present invention, the plate is disposed so that the convex surface of the plate faces the conveying surface. According to the invention, the plate-like body is arranged such that the large convex portion of the undulating surface faces the conveying surface. As a result, it is possible to prevent the plate-shaped member from coming into contact with the transfer surface during the floating transfer of the plate-shaped member. According to these inventions,
When transporting a plate-shaped object, it is only necessary to unify the arrangement of the plate-shaped object with respect to the transport surface, so that the surface is curved, or in order to prevent contact between the plate-shaped object with undulation generated on the surface and the transport surface The use of a special device or the like can be eliminated.

According to the third aspect of the present invention, it is possible to carry out the levitation and conveyance in accordance with the curved state of the plate by simply changing the amount of gas required for the levitation and the conveyance.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a levitation transport method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining how a wafer placed opposite to FIG. 1 floats;

FIG. 3 is an explanatory diagram for explaining how the wafer of FIG. 2 stops.

FIG. 4 is an explanatory diagram for explaining how to stop a wafer that is asymmetrically curved.

FIG. 5 is an explanatory diagram for explaining a floating transfer method when the wafer of FIG. 1 is inclined.

FIG. 6 is an explanatory diagram for explaining how the wafer of FIG. 4 floats.

FIG. 7 is an explanatory diagram for explaining how another wafer floats.

FIG. 8 is an explanatory diagram for explaining how another wafer floats.

FIG. 9 is an explanatory diagram for explaining how another wafer floats.

FIG. 10 is an explanatory diagram for explaining how another wafer floats.

FIG. 11 is a configuration diagram showing a system for transferring a wafer.

FIG. 12 is an explanatory diagram for explaining a state of gas ejection.

[Explanation of symbols]

 1-6, 201 Wafer 1A-4A Convex surface 1B Concave surface 1C Peripheral portion 3B, 4B The other surface 5A, 6A Convex surface portion 10, 111-113 Transport path 11, 111A-113A Transport surface 91 Flow direction 92 Arrow 101, 102 Processing device 211 Transport direction 212, 213 Ejection direction

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masayuki Tsujimura 568, Tanaka, Kawamotomachi, Osato-gun, Saitama Prefecture Wacom Denso Co., Ltd. 72) Inventor Masashi Inami 568, Tanaka, Kawamoto-machi, Osato-gun, Saitama Prefecture Wacom Denso Co., Ltd. (72) Inventor Takahiro Hatanaka 568, Tanaka, Kawamoto-machi, Osato-gun, Saitama Prefecture Wacom Denso Co., Ltd. 2-7-139 Higashi, Yonezawa-shi (72) Inventor Masaki Kusuhara 4-2-1, Nihonbashi Muromachi, Chuo-ku, Tokyo F-term (reference) 5F031 CA02 CA05 GA62

Claims (3)

[Claims] 1. A plate-like body having a convex surface at least a part of which is convexly curved, wherein said plate-like body is disposed with respect to said transport surface such that said convex surface faces a transport surface; And floating along the transport surface by floating the device from the transport surface. 2. Instead of the plate-like body, a plate-like body including a convex portion larger than the undulation on a surface having undulations,
The levitation transport method according to claim 1, wherein the plate-like body is disposed on the transport surface such that the convex portion faces the transport surface. 3. The levitation transport method according to claim 1, wherein a gas is ejected from the transport surface to float and transport the plate-like body.