CN117800088A

CN117800088A - Transport device and in-line vacuum processing device with same

Info

Publication number: CN117800088A
Application number: CN202310907147.8A
Authority: CN
Inventors: 深尾万里; 泽森朗; 久保隼; 远藤茂
Original assignee: Ulvac Inc
Current assignee: Ulvac Inc
Priority date: 2022-09-30
Filing date: 2023-07-24
Publication date: 2024-04-02
Also published as: KR20240046037A; JP2024052317A

Abstract

The invention provides a transport device with high reduction effect of operation cost, which is used for transporting a transport tray capable of arranging a processed substrate in a state that a processing surface of the processed substrate is opened in one direction in a vacuum chamber. The transport device (TM) is provided with a pair of transport units (Tm 1, tm 2), each transport unit comprising: a conveyor belt (23 a, 23 b) wound between two rotating members (21 a, 21b, 22a, 22 b) disposed with a space therebetween in the conveying direction of the conveying tray and traveling around; and a plurality of support rollers (24) for supporting the portion of the conveyor belt on which the conveyor tray is placed. The conveyor belts are configured to be deformed preferentially over the conveyor trays when the conveyor belts are synchronously moved around and the conveyor trays placed on the conveyor belts are repeatedly transported in the X-axis direction.

Description

Transport device and in-line vacuum processing device with same

Technical Field

The present invention relates to a transport device for transporting a transport tray capable of opening a processing surface of a substrate to be processed in one direction in a vacuum chamber, and an inline vacuum processing apparatus.

Background

For example, in the process of manufacturing a flat panel display, there is a process of sequentially forming an organic film or a metal film on one surface (film formation surface) of a substrate to be processed (hereinafter referred to as "substrate") such as a glass substrate by a vacuum vapor deposition method. In such a process, an inline vacuum deposition apparatus is generally used. As a vacuum film forming apparatus of such a vacuum processing apparatus, there is provided a vacuum chamber having a long side in one direction, in which a plurality of film forming sources are arranged, and a transport apparatus for transporting a substrate in the direction in which the film forming sources are arranged is provided (for example, refer to patent document 1). In this case, the substrate is transported in a state where the processing surface thereof is opened and is set on the transport tray. In addition, with the recent increase in the area of the substrate, the total weight including the substrate and the transport tray may reach several hundred kg.

The transport device includes a pair of transport units arranged with an interval in the Y-axis direction, with the X-axis direction and the Y-axis direction being orthogonal to each other in the substrate plane. Each transport unit has a plurality of driving rollers as rotating members, which are provided on the side walls of the vacuum chamber facing each other at predetermined intervals in the X-axis direction. The transport tray placed across the driving rollers is transported downstream in the X-axis direction while being exchanged between the driving rollers. In such a transport device, for example, collision of the transport tray with the drive roller at the time of changing the transport tray to each drive roller, abrasion on the sliding surface of the transport tray with the drive roller, and the like are unavoidable. In this case, if the outer peripheral surface of the driving roller is designed to be deformed preferentially due to wear or the like, vibration during transportation of the transport tray increases, and the substrate is likely to shift in position in the transport tray or the transport speed of the transport tray is likely to deviate. Such a transportation problem may prevent film formation with a fixed film thickness on the film formation surface of the substrate provided on each transportation tray with high accuracy. Therefore, it is generally designed that the transport tray is preferentially deformed (i.e., the transport tray is used as a consumable product) compared to the driving roller.

However, the transport trays used in the inline vacuum processing apparatus are 1 set of a plurality of transport trays, and a plurality of sets are prepared for maintenance. In order to maintain a high product yield, the entire group is generally replaced when the transport trays of each group are used for a predetermined time. In this way, the transport pallet is replaced periodically as a consumable, and there is a problem in that the operation cost increases.

Prior art literature

Patent literature

Japanese patent No. 6179908 (patent document 1)

Disclosure of Invention

Technical problem to be solved by the invention

In view of the above, an object of the present invention is to provide a transport device having a high reduction effect of running cost and a vacuum processing apparatus including the transport device.

Means for solving the technical problems

In order to solve the above-described problems, a transport apparatus according to the present invention for transporting a transport tray capable of being provided in a state where a processing surface of a substrate to be processed is opened in one direction in a vacuum chamber, the transport apparatus comprising: the apparatus includes a pair of transport units disposed with an interval in a Y-axis direction, the transport units being disposed in the X-axis direction and the Y-axis direction in a direction orthogonal to each other in a surface of a substrate to be processed, each transport unit including: a transport belt wound between two rotating members disposed with a space in the X-axis direction and traveling around; and a plurality of support rollers disposed at intervals in an X-axis direction and supporting a portion of the conveyor belt on which the transport tray is placed; the transport belt is configured to be deformed preferentially over the transport tray when the transport tray placed astride the transport belts is repeatedly transported in the X-axis direction while the transport belts of the pair of transport units are synchronously moved around.

In the present invention, when the transport tray is transported in the vacuum chamber, a transport belt made of, for example, steel, which functions as a buffer material is interposed between the rotary member and the back surface of the transport tray, and the transport belt is used as a consumable item to be deformed preferentially, and 2 transport belts are replaced as needed. Therefore, compared with the case where the transport pallet itself is replaced periodically as a consumable product as in the conventional example described above, the operation cost can be significantly reduced. Further, compared with the conventional example using the driving roller, the vibration at the time of transportation can be suppressed as much as possible, and the deviation of the transportation speed can be reduced. Thus, when a single-layer film or a multi-layer film is formed on the film formation surface of the substrate to be processed, the film formation process can be performed with high accuracy and with a fixed film thickness.

However, when the transport pallet is repeatedly placed on the upstream side in the X-axis direction so as to be placed between a pair of transport belts, and the transport belts are moved around in synchronization with each other, the transport pallet is transported to the downstream side in the X-axis direction, and the deformation caused by elongation is also caused in addition to abrasion (for example, slip marks) between the transport pallet and the transport belts among the deformations generated in the transport belts. Moreover, when the conveyor belt is elongated, a deviation of the conveying speed occurs. The invention can adopt the following structure: the device is provided with a biasing mechanism for biasing at least one of the rotating members in a direction away from each other in the X-axis direction, and the biasing mechanism is configured to displace at least one of the rotating members in the X-axis direction to maintain tension applied to the conveyor belt when the conveyor belt is (elastically) deformed. This makes it possible to avoid the need to intentionally open the atmosphere in the vacuum chamber and readjust the tension of the conveyor belt, and to always maintain a small variation in the conveying speed.

On the other hand, if the conveyor belt is (plastically) deformed by elongation exceeding the predetermined range, the tension applied to the conveyor belt cannot be maintained. In this case, it is also conceivable to replace the conveyor belt periodically, but the elongation of the conveyor belt varies depending on the weight of the conveyor tray and the conveying conditions such as the conveying speed. Therefore, unnecessary tape replacement can preferably be prevented. In the present invention, a structure may be adopted that further includes a detector that detects a displacement amount of at least one of the rotating members. Thus, for example, if the detected value in the detector is introduced into the control unit of the vacuum processing apparatus or the transport apparatus, and if the belt replacement is notified when the introduced value exceeds a preset threshold value, the replacement timing of the transport belt can be appropriately determined, and unnecessary belt replacement can be prevented. In addition, if an image pickup device such as a CCD camera is provided to monitor the wear state of the slip mark or the like generated on the conveyor belt, and the belt replacement is also judged based on the image analysis, the transportation problem associated with the deformation of the conveyor belt can be reliably prevented.

In order to solve the above-described problems, the in-line vacuum processing apparatus according to the present invention further includes a vacuum processing unit for performing a predetermined vacuum process on the substrate to be processed in the vacuum chamber, in addition to the transport apparatus. And a control unit for controlling at least one of the transportation device and the vacuum processing unit, wherein the control unit is communicably connected to the detector, and notifies the belt replacement related information based on the detection value of the detector.

Drawings

Fig. 1 is a cross-sectional view illustrating a configuration of an inline vacuum film forming apparatus including a transport apparatus according to the present embodiment.

Fig. 2 is a sectional view taken along line II-II of fig. 1.

Fig. 3 is a cross-sectional view taken along line III-III of fig. 2.

Fig. 4 is a cross-sectional enlarged view of a portion surrounded by a chain line of fig. 3.

Fig. 5 is a sectional view taken along line V-V of fig. 4.

Detailed Description

Hereinafter, embodiments of a transport apparatus TM and an in-line film forming apparatus CM provided with the transport apparatus TM according to the present invention will be described by taking an in-line vacuum processing apparatus as a vacuum film forming apparatus, and taking a glass substrate having a rectangular outline (hereinafter referred to as a "substrate Sg") as a substrate to be processed, transporting the substrate Sg in a state where the substrate Sg is set on a transport tray Tc, and forming a multilayer film on one side (film forming surface Sg 1) of the substrate Sg by a vacuum vapor deposition method, as an example. The directions orthogonal to each other in the plane of the substrate Sg are hereinafter referred to as X-axis direction and Y-axis direction, the direction from the film formation source side to the substrate Sg to be described later is referred to as Z-axis direction upward, and the substrate Sg moves from the left side to the right side in fig. 1, and the term indicating the direction is used as a reference.

Referring to fig. 1 and 2, a vacuum film forming apparatus CM including a transport apparatus TM according to the present embodiment includes first to third film forming chambers Pc1, pc2, and Pc3 that are disposed continuously to each other and have long sides in the X-axis direction. A vacuum pump (not shown) is connected to each of the first to third film forming chambers Pc1, pc2, and Pc3, and the film forming space therein can be formed into a vacuum atmosphere having a predetermined pressure. In the first to third film forming chambers Pc1, pc2, pc3, film forming sources 1a, 1b, 1c are provided on the same axis in the X axis direction. The film forming sources 1a, 1b, and 1c have the same configuration, and include: a crucible 11 for accommodating a film forming material Vm; and a heating mechanism 12 for heating the film forming material Vm of the crucible 11. The film forming material Vm is appropriately selected according to the composition of each thin film to be laminated on the substrate Sg. As the heating means 12, a resistance heating method, an induction heating method, or an electron gun method is used according to the type of the film forming material Vm. Each of the film forming sources 1a, 1b, and 1c further includes a shutter 13 rotatably covering the upper surface discharge port 11a of the crucible 11 to prevent the film forming material Vm from reaching the substrate Sg.

The load lock chambers Lc1, lc2 are continuously provided on the upstream side in the X-axis direction of the first film forming chamber Pc1 and the downstream side in the X-axis direction of the third film forming chamber Pc3, respectively, with the gate valves GV1, GV 2. Although not particularly illustrated, the load lock chambers Lc1 and Lc2 are connected to a vacuum pump and a vent valve, respectively, and the inside thereof can be rapidly switched between an air atmosphere and a vacuum atmosphere. Then, the transport tray Tc provided with the pre-processed substrate Sg is transported to the load lock chamber Lc1 on the upstream side, and the processed substrate Sg is transported out of the load lock chamber Lc2 on the downstream side together with the transport tray Tc.

The transport tray Tc is made of a material that does not affect the film formation process even when used in a vacuum atmosphere, such as a plate made of stainless steel, invar, or aluminum, and a rectangular opening Tc1 (see fig. 2) is formed to face the film formation surface Sg1 of the substrate Sg, and the substrate Sg is placed on the upper surface of the transport tray Tc with the processing surface Sg1 facing downward. The transport device TM according to the present embodiment is provided in each of the film forming chambers Pc1, pc2, and Pc3 so as to transport the transport tray Tc provided with the substrate Sg from the load lock chamber Lc1 on the upstream side to the load lock chamber Lc2 on the downstream side through the inside of each of the film forming chambers Pc1, pc2, and Pc3.

Referring also to fig. 3 to 5, the transport apparatus TM includes a pair of transport units TM1, TM2 disposed on both side walls of the film forming chambers Pc1, pc2, pc3 facing each other in the Y-axis direction. Each of the transport units Tm1 and Tm2 has the same structure, and includes: driving pulleys 21a, 21b and driven pulleys 22a, 22b as rotating members provided at both ends of the first to third film forming chambers Pc1, pc2, pc3 in the X axis direction, respectively; conveyor belts 23a, 23b wound between the driving pulleys 21a, 21b and the driven pulleys 22a, 22b; and a plurality of support rollers 24 that are provided at intervals in the X-axis direction and support portions of the conveyor belts 23a, 23b on which the conveying tray Tc is placed. Further, both outer ends of the transport tray Tc along the Y-axis direction are provided on the respective transport belts 23a, 23b so as to be interposed between the pair of transport belts 23a, 23b, respectively. The support rollers 24 having diameters smaller than those of the drive pulleys 21a, 21b and the driven pulleys 22a, 22b are supported on the side walls of the film forming chambers Pc1, pc2, pc3 so as to be rotatable as the conveyor belts 23a, 23b travel around. As the backup roller 24, for example, a backup roller made of stainless steel or carbon steel (S45C: quenching material) or a surface-treated product such as hard chrome plating is used so as not to adversely affect the film forming process in each of the film forming chambers Pc1, pc2, and Pc3. The interval between the adjacent support rollers 24 in the X-axis direction is set appropriately according to the length of the transport tray Tc in the X-axis direction.

Drive shafts 31a, 31b of motors 3a, 3b inserted in the side walls of the respective film forming chambers Pc1, pc2, pc3 while ensuring internal air tightness are connected to drive pulleys 21a, 21b provided on the downstream end side in the X axis direction. The driven pulleys 22a, 22b are attached to the side walls of the respective film forming chambers Pc1, pc2, pc3 by urging means 4 that urges in a direction away from the driving pulleys 21a, 21b in the X-axis direction (left direction in fig. 4). In this case, a base plate 51 having a long side in the X-axis direction is provided on the side wall of each of the film forming chambers Pc1, pc2, pc3, and 2 rail members 52 extending in the X-axis direction are attached to the inner surface of the base plate 51 with a gap therebetween in the Z-axis direction, and the movable plate 53 is engaged with the rail members 52 so as to be slidable in the X-axis direction. The driven pulleys 22a and 22b are respectively fitted to the front end portions of the shaft bodies 54 standing on the rail members 52 via bearings 55. On the inner surface of the base plate 51, a fixed plate 56 is provided with a space from the movable plate 53 to the downstream side in the X-axis direction.

A receiving hole 56a extending in the X-axis direction is concavely provided on a portion of the fixed plate 56 opposite to the movable plate 53, and a spring seat 53a is mounted on a portion of the movable plate 53 opposite to the fixed plate 56. A coil spring as the biasing means 4 is compressed between the spring seat 53a and the receiving hole 56 a. The biasing force of the coil spring 4 is set so that the tension applied to the conveyor belts 23a, 23b is always maintained within a predetermined range. At this time, the urging force of the coil spring 4 can be adjusted by the adjusting bolt 6 provided on the fixing plate 56. A detection piece 53b having a length extending upward in the Z-axis direction from the base plate 51 is provided on the upper surface of the movable plate 53, and the reflection type laser sensor 7 as a detector is mounted on the base plate 51 so as to face a portion of the detection piece 53 b. Then, the laser light is irradiated from the laser sensor 7 to the detection piece 53b, and the displacement amounts of the movable pulleys 22a and 22b in the X-axis direction can be detected based on the reflected light amounts thereof.

The conveyor belts 23a and 23b are configured to be deformed preferentially to the transport tray Tc when the transport device TM repeats the transport of the transport tray Tc in the X-axis direction, and are appropriately selected to be materials that do not adversely affect the vacuum process even when used in a vacuum atmosphere. For example, when the total weight of the transport tray Tc in the state where the substrate Sg is provided is in the range of 50kg to 1200kg, the transport belts 23a, 23b may be constituted by a steel product having a width in the range of 40mm to 60mm and a thickness in the range of 0.15mm to 0.30 mm. As the deformation generated in the conveyor belts 23a, 23b, there are, in addition to abrasion (for example, slip marks) accompanying the surface contact with the support plate portion Tc3 of the conveyor tray Tc, deformation caused by elongation accompanying the phenomenon of equivalent rolling when sandwiched between the drive pulleys 21a, 21b, the driven pulleys 22a, 22b or the support roller 24 and the conveyor tray Tc. When the conveyor belts 23a, 23b are deformed in an elongated manner, the movable plate 53 and thus the driven pulleys 22a, 22b are displaced relative to the fixed plate 56 in a direction away from the driving pulleys 21a, 21b in the X-axis direction by the biasing force of the coil spring 4, and the tension applied to the conveyor belts 23a, 23b is maintained, and the displacement amount at this time is detected by the laser sensor 7. In the figure, pp is an adhesion preventing plate for preventing the adhesion of a film to each component of the transport device TM.

The vacuum film forming apparatus CM includes a control unit Cu including a computer, a memory, a sequencer, and the like. The control unit Cu controls the operation of the transport device TM in a unified manner, in addition to the components that operate during film formation, such as the film formation sources 1a, 1b, 1c, and the vacuum pump. In this case, although not particularly illustrated, the control unit Cu is provided with a display for displaying the operation state of each component or the transport device TM. The control unit Cu is also inputted with the displacement amount detected by being communicatively connected to the laser sensor 7. When the input displacement exceeds a threshold value set in advance in the control unit Cu, the display of the control unit Cu can be notified that the conveyor belts 23a, 23b have reached the replacement time by sound or image.

When a multilayer film is formed on the processing surface Sg1 of the substrate Sg by the vacuum film forming apparatus CM, the transport tray Tc on which the substrate Sg before processing is set in advance is transported to the load lock chamber Lc1 on the upstream side of the atmosphere. In this case, the inside of each of the film forming chambers Pc1, pc2, pc3 is evacuated by a vacuum pump to be maintained at a predetermined pressure, and the film forming material Vm of the crucible 11 is heated by the heating mechanism 12 in each of the film forming sources 1a, 1b, 1c. At this time, the discharge opening 11a of the upper surface of the crucible 11 is shielded by the shutter 13. When the load lock chamber Lc1 on the upstream side is evacuated to a predetermined pressure, the gate valve Gv1 is opened, and the transport tray Tc is transferred from the load lock chamber Lc1 on the upstream side to the transport device TM in the first film forming chamber Pc1 so as to straddle the transport belts 23a, 23b of the pair of transport units TM1, TM2. When the conveyor belts 23a, 23b are driven to rotate in synchronization by the motors 3a, 3b, the conveyor tray Tc is conveyed downstream in the X-axis direction, and then is replaced on the conveyor TM in the second and third film forming chambers Pc2, pc3 to be conveyed. During the transportation, the shutter 13 is appropriately retracted, so that the film forming material Vm discharged from the crucible 11 according to a predetermined cosine law due to vaporization or sublimation adheres to and deposits on the film forming surface Sg1 of the substrate Sg through the opening Tc4, thereby forming a multilayer film on the processing surface Sg 1. Then, when the transport tray Tc is transported to the most downstream side in the third film forming chamber Pc3, the gate valve Gv2 is opened, the transport tray Tc having the processed substrate Sg is transported to the load lock chamber Lc2 on the downstream side, and after the gate valve Gv2 is closed, the atmosphere is opened and recovered.

With the above embodiment, when the transport pallet Tc is repeatedly placed so as to straddle between the pair of transport belts 23a, 23b of each transport device TM and the transport belts 23a, 23b are made to travel in synchronization around each other, and the transport pallet Tc is transported downstream in the X-axis direction, steel transport belts 23a, 23b functioning as cushioning materials are provided between the driving pulleys 21a, 21b, the driven pulleys 22a, 22, and the back surface of the support roller 24 and the support plate portion Tc3 of the transport pallet Tc, and the transport belts 23a, 23b are used as consumables that are deformed preferentially. Accordingly, since the 2 conveyor belts 23a and 23b need to be replaced as needed, the running cost can be significantly reduced compared to the case where the conveyor tray Tc itself is replaced regularly as a consumable product as in the conventional example described above. Further, compared with the conventional example using the driving roller, the vibration at the time of transportation can be suppressed as much as possible, and the deviation of the transportation speed can be reduced. Thus, when a multilayer film is formed on the film formation surface Sg1, the film formation process can be performed with high accuracy and with a fixed film thickness.

Further, when the conveyor belts 23a, 23b are elongated, the driven pulleys 22a, 22b are relatively displaced in the X-axis direction by the urging force of the coil springs 4, and the tension applied to the conveyor belts 23a, 23b is maintained, so that it is unnecessary to intentionally open the atmosphere of the film forming chambers Pc1, pc2, pc3 and readjust the conveyor belts 23a, 23b, and it is possible to always maintain the variation in the conveying speed as small as possible. Further, since the belt replacement device is provided with the detector 7 for detecting the displacement amount of the driven pulleys 22a and 22b, and the control unit Cu is configured to introduce the detection value of the detector 7, if the introduced value exceeds the preset threshold value, the belt replacement device can notify the replacement of the belt, so that the replacement timing of the conveyor belts 23a and 23b can be appropriately determined, and unnecessary belt replacement can be prevented. Further, although not particularly illustrated, if imaging devices such as CCD cameras are provided in the respective film forming chambers Pc1, pc2, pc3 in order to monitor the wear state of the transport belts 23a, 23b such as the slip marks, and if the belt replacement is determined based on the image analysis, the transport problems associated with the deformation of the transport belts 23a, 23b can be reliably prevented.

The embodiments of the present invention have been described above, but various modifications are possible without departing from the scope of the technical idea of the present invention. In the above embodiment, the film formation process by the vacuum vapor deposition method was described as an example of the vacuum process, but the present invention is not limited thereto. The present invention can also be applied to a case where a film formation process or a dry etching process is performed by a sputtering method or a CVD method. Further, the description has been made using the coil spring 4 as an example of the biasing means, but the conveyer belts 23a, 23b are not limited to this, and other biasing means such as a leaf spring may be used as long as they can relatively displace the driven pulleys 22a, 22b in the X-axis direction according to the deformation, and the driving pulleys 21a, 21b may be configured to relatively displace in the X-axis direction instead of or in addition to the driven pulleys 22a, 22b. Further, the description has been made taking the example of the sensor using the laser sensor 7 as the detector 7 for detecting the displacement amount of the driven pulleys 22a, 22b, but the present invention is not limited thereto, and other sensors such as a micro switch may be used.

In the above embodiment, the case where the two outer ends of the transport tray Tc in the Y axis direction are directly provided on the respective transport belts 23a, 23b is described as an example, but the present invention is not limited thereto. Since the surface (contact surface) of the transport tray Tc on each of the transport belts 23a and 23b is particularly easily worn, a sheet made of stainless steel such as SUS440C having high hardness (material having high wear resistance) may be attached only to the surface. Further, if the sheet is replaced only when damaged for some reason, the effect of reducing the running cost can be further improved (that is, the transport tray itself is not used as a consumable part).

Description of the reference numerals

CM. A series of vacuum film forming apparatuses (vacuum processing apparatuses), TM. transport apparatuses, cu. control units, tc. transport trays, tm1, tm2 transport units, 21a, 21b, driving pulleys (rotating members), 22a, 22b, driven pulleys (rotating members), 23a, 23b, transport belts, 24, backup rollers, 4, coil springs (biasing mechanisms), 7, laser sensors (detectors).

Claims

1. A transport device for transporting a transport tray capable of setting a substrate to be processed in a state in which a processing surface thereof is opened in one direction in a vacuum chamber, characterized in that:

the apparatus includes a pair of transport units disposed with an interval in a Y-axis direction, the transport units being disposed in the X-axis direction and the Y-axis direction in a direction orthogonal to each other in a surface of a substrate to be processed, each transport unit including: a transport belt wound between two rotating members disposed with a space in the X-axis direction and traveling around; and a plurality of support rollers disposed at intervals in an X-axis direction and supporting a portion of the conveyor belt on which the transport tray is placed;

the transport belt is configured to be deformed preferentially over the transport tray when the transport tray placed astride the transport belts is repeatedly transported in the X-axis direction while the transport belts of the pair of transport units are synchronously moved around.

2. The transport device of claim 1, wherein:

the conveyor belt is provided with a biasing mechanism for biasing at least one of the rotating members in a direction away from each other in the X-axis direction, and when the conveyor belt is deformed, the at least one of the rotating members is displaced in the X-axis direction by the biasing force of the biasing mechanism, thereby maintaining tension applied to the conveyor belt.

3. A transportation device according to claim 2, characterized in that:

the rotary member is provided with a detector for detecting a displacement amount of at least one of the rotary members.

4. An inline vacuum processing apparatus comprising:

a transportation device as claimed in claim 3; and a vacuum processing unit configured to perform a predetermined vacuum process on the target substrate in the vacuum chamber.

5. The inline vacuum processing apparatus according to claim 4, wherein:

and a control unit for controlling the operation of at least one of the transport device and the vacuum processing unit, wherein the control unit is communicably connected to the detector, and notifies the belt replacement related information based on the detection value of the detector.