TECHNICAL FIELD

The present invention relates to a substrate guide and a carrier, and more particularly to a technology suitably used for preventing occurrence of breakage or the like of a substrate in vertical transfer.

Priority is claimed on Japanese Patent Application No. 2017-113650, filed in Japan on Jun. 8, 2017, the content of which is incorporated herein by reference.

BACKGROUND ART

For example, in a manufacturing process of a liquid crystal display, a thin film transistor (TFT) is formed on a substrate made of glass or the like. In formation of the TFT, film formation apparatuses (sputtering apparatus) for performing a heat treatment, a deposition process, and the like on a glass substrate in a vacuum environment are used.

In recent years, as liquid crystal displays have become larger in size, a carrier circulation type in-line sputtering apparatuses has been used as a film formation apparatus. This carrier circulation type in-line sputtering apparatus includes a preparation chamber in which a glass substrate is introduced into a vacuum, a deposition chamber in which a sputtering target is disposed, and an extraction chamber for returning the glass substrate from a vacuum state to the atmosphere, and the like. Then, the glass substrate is placed on a transfer truck called a carrier and is moved between chambers constituting the in-line sputtering apparatus (see Patent Document 1, for example).

Also, for a sputtering apparatus, a configuration of a vertical type single-wafer-processing apparatus (fixed film formation apparatus) or an inter-back type sputtering apparatus is also known.

In an inter-back type sputtering apparatus, one chamber serves as both a preparation chamber into which a glass substrate is introduced and an extraction chamber from which the glass substrate is extracted.

Regarding a carrier on which a glass substrate is placed, in order to keep an installation area of an in-line sputtering apparatus to a minimum, a so-called vertical carrier in which a glass substrate is held in a state of standing in a substantially vertical direction is increasingly used. Such a vertical carrier includes a frame that holds a peripheral edge portion of a glass substrate by being in contact therewith. In this frame, an opening for exposing one deposition surface side of the glass substrate is formed.

When a glass substrate is loaded into an in-line sputtering apparatus, for example, a horizontally placed glass substrate is picked up by an articulated robot arm having a suction disc or the like. Next, the glass substrate is rotated in a state of standing in a vertical direction, and the glass substrate is rested on a frame of the carrier. When the articulated robot arm releases the suction of the glass substrate, the glass substrate sinks to a position at which a bottom side of the glass substrate comes into contact with a receiving portion at a lower end of the frame due to a weight thereof. Thereafter, a peripheral edge portion of a substrate surface of the glass substrate is pressed by the frame and gripped by clamps or the like attached to the frame.

Also, the glass substrate in a state of being placed in the carrier repeats being accelerated and decelerated when moving between respective chambers of the in-line sputtering apparatus.

In an inter-back type sputtering apparatus, a horizontally maintained glass substrate is received from a transfer machine, and thereafter, the glass substrate is placed in a state of standing in a vertical direction, and the glass substrate is transferred.

In a step of placing a glass substrate on a vertical carrier, there are cases in which a deviation of approximately several millimeters is caused in a placement position of the glass substrate due to constraints of driving precision of the articulated robot arm. While a glass substrate has a tolerance (dimensional error) of approximately 0.1%, in a large glass substrate with one side of several meters, for example, this appears as a variation of several millimeters even with the tolerance of 0.1%.

Also, in a large glass substrate with one side of several meters, the weight thereof may reach several kilograms to several tens of kilograms, and the thickness thereof may be extremely thin and on the millimeter order or 0.1 mm order. Therefore, a load of an extremely large glass substrate is applied to an end surface of the glass substrate in vertical transfer.

PRIOR ART DOCUMENTS

Patent Documents

(Patent Document 1) Japanese Unexamined Patent Application, First Publication No. 2006-114675

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

In an in-line sputtering apparatus in which a glass substrate is vertically transferred in manufacture of a liquid crystal display or the like, when breakage or the like occurs in the glass substrate, it is necessary to stop the entire manufacturing line. When a period of operation stoppage occurs in the manufacturing line, significant deterioration in workability is caused. Therefore, there is a demand to prevent occurrence of breakage in glass substrates which causes operation stoppage in manufacturing lines.

In regards to places on a glass substrate in which breakage/cracking occur in vertical transfer, since breakage/cracking often occur near a substrate support which is at a lower position on a carrier to which a weight of the substrate is applied, there is a particularly strong demand to solve this problem.

Also, as a case in which breakage/cracking occur in a glass substrate, when acceleration and deceleration are repeated with the glass substrate placed on a carrier, since breakage/cracking may occur also at a position near a substrate position restricting portion which is at front and rear positions of the carrier, there is a demand to solve this problem.

The present invention has been made in view of the above circumstances, and it is intended to achieve an object of curtailing occurrence of breakage/cracking in a glass substrate placed on a carrier in vertical transfer.

Means for Solving the Problems

The present inventors have conducted intensive research and found out that the following matters relate to a cause of breakage in a glass substrate.

When a substrate is transferred by a carrier or when a substrate is replaced with respect to the carrier, there are cases in which movement or rubbing of the substrate occurs with respect to the carrier. In this way, when movement or rubbing impact of the substrate with respect to the carrier occurs, there is a likelihood of damage to an end surface of the substrate. Since the thickness of a glass substrate transferred by a carrier of a vertical transfer is extremely thin, damage to an end surface of the substrate is extremely large. Therefore, breakage occurs in the glass substrate due to the damage. Therefore, the present inventors have realized the present invention, particularly as a configuration capable of reducing damage to a substrate in a substrate support positioned at a lower position on a carrier in which such a problem occurs. Further, the present inventors researched the same also for a case in which acceleration and deceleration are repeated with the glass substrate placed on the carrier, and realized the present invention.

A substrate guide according to a first aspect of the present invention is provided on a carrier frame of a carrier which holds a substrate substantially vertically so that a surface of the substrate is in a substantially vertical direction and supports the substrate by being in contact with at least a peripheral edge end surface portion of the substrate, and, in order to solve the above problem, the substrate guide includes a base attached to the carrier frame, a substrate support which comes into contact with the peripheral edge end surface portion of the substrate held by the carrier and is attached to the base to be movable in a normal direction of the peripheral edge end surface portion in a direction parallel to the surface of the substrate, and a force-applying member which applies a force to the substrate support toward the substrate with respect to the base.

In the substrate guide according to the first aspect of the present invention, it is more preferable that the substrate support include a planar support along the peripheral edge end surface portion.

In the substrate guide according to the first aspect of the present invention, the substrate support and the base can include movement position restricting sliding surfaces that slide relative to each other in a direction perpendicular to the planar support.

In the substrate guide according to the first aspect of the present invention, the base may include a contact portion which comes into contact with the surface of the substrate adjacent to the peripheral edge end surface portion when the substrate is placed on the substrate support, and the contact portion may extend in a direction away from the planar support in a moving direction of the substrate support.

In the substrate guide according to the first aspect of the present invention, the base can have a contour shape separated from the planar support in the moving direction of the substrate support except for the contact portion.

In the substrate guide according to the first aspect of the present invention, it is preferable that a surface separated from the substrate in a direction along the surface of the substrate be connected to an end portion of the planar support separated from the contact portion.

In the substrate guide according to the first aspect of the present invention, a length of the substrate support in a direction from the peripheral edge end surface portion toward a position separated from the contact portion can be set such that the substrate support covers the base.

In the substrate guide according to the first aspect of the present invention, the force-applying member can be provided at least at both end positions of the planar support of the substrate support in a peripheral direction of the peripheral edge end surface portion.

In the substrate guide according to the first aspect of the present invention, the substrate support and the base can include an accommodating recess in which an end portion of the force-applying member is accommodated.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and a central axis of the coil spring can be disposed at a position intersecting the planar support.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and a central axis of the coil spring may be disposed at a position closer to the contact portion than the movement position restricting sliding surface is.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and an edge portion of the coil spring is disposed at a position further away from the contact portion than from the movement position restricting sliding surface.

A carrier according to a second aspect of the present invention holds a substrate substantially vertically so that a surface of the substrate is in a substantially vertical direction, and the carrier includes a carrier frame supporting the substrate by being in contact with at least a peripheral edge portion of the substrate, in which a plurality of substrate guides described in any one of the above can be disposed in the carrier frame.

The substrate guide according to a first aspect of the present invention is provided on a carrier frame of a carrier which holds a substrate substantially vertically so that a surface of the substrate is in a substantially vertical direction and supports the substrate by being in contact with at least a peripheral edge end surface portion of the substrate, and the substrate guide includes a base attached to the carrier frame, a substrate support which comes into contact with the peripheral edge end surface portion of the substrate held by the carrier and is attached to the base to be movable in a normal direction of the peripheral edge end surface portion in a direction parallel to the surface of the substrate, and a force-applying member which applies a force to the substrate support toward the substrate with respect to the base. Thus, when the substrate is placed on the carrier, the substrate support with which the peripheral edge end surface portion of the substrate is in contact can be moved in a direction extending toward a periphery of the frame which is a direction in which a load is applied to the carrier frame (base). Therefore, an impact on the peripheral edge end surface portion of the substrate can be alleviated, and the substrate support with which the peripheral edge end surface portion of the substrate is in contact is movable with respect to the base integrated with the carrier frame even when the carrier is moved in a state in which the substrate is placed in the carrier. Thus, it is possible to alleviate an impact on the peripheral edge end surface portion of the substrate, thereby making it possible to sufficiently curtail occurrence of breakage/defects in the substrate.

Further, in the substrate guide according to the first aspect of the present invention, both the direction of a surface of the substrate and the direction of the peripheral edge end surface portion of the substrate mean directions in a state in which the surface of the substrate is held in the vertical direction. Also, the substrate has a substantially rectangular contour shape.

In the substrate guide according to the first aspect of the present invention, the substrate support includes a planar support along the peripheral edge end surface portion. Thus, since the planar support is a flat surface and no protrusion is provided, when the substrate is placed on the carrier, the planar support extends in a direction in which the peripheral edge end surface portion of the substrate moves. Therefore, it is possible to prevent occurrence of breakage/defects in the substrate caused by the peripheral edge end surface portion of the substrate being caught by the planar support.

In the substrate guide according to the first aspect of the present invention, the substrate support and the base include movement position restricting sliding surfaces that slide relative to each other in a direction perpendicular to the planar support. Thereby, the substrate support and the base can slide along the movement position restricting sliding surfaces in a direction perpendicular to the planar support. Therefore, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, it is possible to alleviate a load/impact on the substrate in the in-plane direction and to prevent occurrence of breakage/defects in the substrate.

Further, the movement position restricting sliding surfaces can be provided in a direction parallel to the surface of the substrate.

Further, the movement position restricting sliding surfaces can also be provided in a direction perpendicular to the surface of the substrate.

In the substrate guide according to the first aspect of the present invention, the base includes a contact portion which comes into contact with the surface of the substrate adjacent to the peripheral edge end surface portion when the substrate is placed on the substrate support and the contact portion extends in a direction away from the planar support in a moving direction of the substrate support. Thereby, since the surface (surface) of the substrate does not come into direct contact with the carrier frame, problems occurring in the substrate due to being in contact with the carrier frame such as a substrate temperature state can be avoided. Further, since the contact portion is provided on the base, in a state in which the peripheral edge end surface portion is in contact with the substrate support, the substrate can be placed on the substrate support by restricting a position of the substrate with respect to the substrate guide at a position at which the surface of the substrate is in contact with the contact portion.

In the substrate guide according to the first aspect of the present invention, the base has a contour shape separated from the planar support in the moving direction of the substrate support except for the contact portion. Thereby, when the substrate is placed on the substrate support, in a state in which the peripheral edge end surface portion is in contact with the substrate support, any portion other than the contact portion constituting the base does not come into contact with the substrate. Therefore, when the substrate is placed on the carrier, since the peripheral edge end surface portion of the substrate does not come into contact with any portion other than the planar support in a moving direction thereof, it is possible to prevent occurrence of breakage/defects in the substrate caused by any portion of the substrate other than the peripheral edge end surface portion being caught by the base.

In the substrate guide according to the first aspect of the present invention, a surface separated from the substrate in a direction along the surface of the substrate is connected to an end portion of the planar support separated from the contact portion. Thus, when the substrate is placed on the carrier, since the surface extending from the planar support is formed to be separated from the substrate before the peripheral edge end surface portion of the substrate comes into contact with the planar support, the peripheral edge end surface portion of the substrate does not come into contact with any portion other than the planar support in front of the planar support in a moving direction thereof. Thereby, it is possible to prevent occurrence of breakage/defects in the substrate caused by any portion other than the peripheral edge end surface portion of the substrate being caught by the substrate support.

In the substrate guide according to the first aspect of the present invention, a length of the substrate support in a direction from the peripheral edge end surface portion toward a position separated from the contact portion is set such that the substrate support covers the base. Accordingly, when the substrate is placed on the carrier, since the peripheral edge end surface portion of the substrate comes into contact with only the substrate support and does not come into contact with the base, it is possible to prevent occurrence of breakage/defects in the substrate caused by the peripheral edge end surface portion of the substrate coming into contact with the base.

In the substrate guide according to the first aspect of the present invention, the force-applying member is provided at least at both end positions of the planar support of the substrate support in a peripheral direction of the peripheral edge end surface portion. Thus, since the substrate support is supported by the base at both ends at which the force-applying members are disposed, the substrate support is prevented from being inclined in the in-plane direction of the substrate and the substrate support can move only in a direction perpendicular to the planar support. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

In the substrate guide according to the first aspect of the present invention, the substrate support and the base include an accommodating recess in which an end portion of the force-applying member is accommodated. Accordingly, the force-applying member is prevented from being deviated with respect to the substrate support and the force-applying member is prevented from being deviated with respect to the base, and thereby it is possible to prevent a moving direction of the substrate support to the base from fluctuating. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and a central axis of the coil spring is disposed at a position intersecting the planar support. Thereby, the substrate support is prevented from being inclined in a normal direction of the surface of the substrate so that the substrate support can move only in a direction perpendicular to the planar support. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and a central axis of the coil spring is disposed at a position closer to the contact portion than the movement position restricting sliding surface is. Thereby, the substrate support is prevented from being inclined in a normal direction of the surface of the substrate so that the substrate support can move only in a direction perpendicular to the planar support. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

In the substrate guide according to the first aspect of the present invention, the force-applying member is a columnar coil spring, and an edge portion of the coil spring is disposed at a position further away from the contact portion than from the movement position restricting sliding surface. Thereby, the substrate support is prevented from being inclined in a normal direction of the surface of the substrate so that the substrate support can move only in a direction perpendicular to the planar support. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

A carrier according to a second aspect of the present invention is a carrier that holds a substrate substantially vertically so that a surface of the substrate is in a substantially vertical direction, and the carrier includes a carrier frame supporting the substrate by being in contact with at least a peripheral edge portion of the substrate, in which a plurality of substrate guides described in any one of the above are disposed in the carrier frame. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

The substrate guide is provided at a lower portion of the carrier frame or at front and rear positions in a traveling direction of the carrier. Thereby, when the substrate is placed on the carrier or when the carrier is moved in a state in which the substrate is placed thereon, it is possible to prevent a local load from being applied to the peripheral edge end surface portion of the substrate in the lower portion of the substrate. Further, a local load is prevented from being applied to peripheral edge end surface portions of the substrate which are the front and rear positions in a traveling direction of the carrier, and thereby occurrence of breakage/defects in the substrate can be prevented.

Effects of the Invention

According to the aspects of the present invention, it is possible to achieve an effect that occurrence of breakage/defects in the substrate can be prevented by preventing a local load from being applied to the peripheral edge end surface portion of the substrate.

