Differential exhaust device

Abstract

The present invention enhances a differential adjustment function of a differential exhaust device, thereby facilitating quick and highly-accurate differential adjustment following a change in pressure setting in a vacuum chamber that performs vacuum processing.　The present invention pertains to a differential exhaust device that is connected to a vacuum chamber that performs vacuum processing on a sheet base material, and is configured to transport the sheet base material while performing differential exhaust, the differential exhaust device comprising: a plurality of decompression chambers that are disposed along a transport direction of the sheet base material and can be independently decompressed and exhausted; a plurality of low-conductance flow passages that are disposed between two of the decompression chambers which are adjacent, and that include gaps through which the sheet base material can be transported; and gap adjustment sections that are respectively provided to the low-conductance flow passages and adjust the gap between the low-conductance flow passages and the sheet base material, wherein each gap adjustment section includes a gap adjustment unit that causes a flow passage surface of the low-conductance flow passage to approach or separate from the sheet base material, the gap adjustment unit includes a differential adjustment component having a flow passage surface on one surface, and a movement mechanism that moves the differential adjustment component in a direction perpendicular to the transport direction of the sheet base material, and the gap adjustment unit is detachably disposed on a housing provided with a decompression chamber and is provided with a seal ring for ensuring airtightness with the housing at the periphery of the differential adjustment component.

Description

Differential Evacuation Apparatus

[0001] The present invention relates to a differential evacuation apparatus that performs differential evacuation while conveying a sheet base material.

[0002] Conventionally, differential evacuation apparatuses have been used in vacuum processing apparatuses that perform various types of processing and film formation in a vacuum chamber on a sheet base material conveyed by roll-to-roll conveyance. This differential evacuation apparatus is provided, for example, between a plurality of vacuum chambers having pressure differences, maintains the processing environment in each vacuum chamber, and can feed the sheet base material into each vacuum chamber while eliminating contamination between the plurality of vacuum chambers (see Patent Documents 1 and 2 below).

[0003] The basic structure of the differential evacuation apparatus connects a plurality of decompression chambers via low-conductance flow paths, so that each decompression chamber is independently decompressed and evacuated (differential evacuation), and the low-conductance flow paths and decompression chambers serve as a conveyance path for the sheet base material. In this case, the pressure setting of each decompression chamber is set according to the pressure difference of the vacuum chambers connected to both sides of the differential evacuation apparatus, and is set so that the pressure changes stepwise from the decompression chamber on one end side toward the decompression chamber on the other end side.

[0004] Japanese Patent No. 6419428, Japanese Patent No. 5325031

[0005] When the above-mentioned differential evacuation apparatus is used, continuous work can be performed while maintaining the vacuum state and temperature state of each vacuum chamber when conveying a sheet base material processed in one vacuum chamber to another vacuum chamber, or when replacing a roll of the sheet base material. In contrast, when a differential evacuation apparatus is not used, it is necessary to convey or replace the sheet base material after each vacuum chamber is once opened to the atmosphere. Therefore, by using the differential evacuation apparatus, the steps required for nitrogen purging performed to recover the processing environment in the vacuum chamber and ensure the quality of the sheet base material can be eliminated. In addition, compared to the case where a differential evacuation apparatus is not used, production efficiency can be improved, and furthermore, the processing quality of the sheet base material can be improved by eliminating contamination through differential evacuation.

[0006] However, conventionally, the differential performance of such differential exhaust systems has been adjusted solely by the exhaust volume of the differential exhaust. Therefore, when the pressure setting in the vacuum chamber changes due to changes in the thickness or material of the sheet substrate, it is difficult to quickly adjust the pressure in the decompression chamber accordingly. Furthermore, adjusting only the differential exhaust makes it difficult to achieve highly accurate differential pressure adjustment.

[0007] Furthermore, for example, when connecting a differential exhaust system to a vacuum drying apparatus that processes at a high degree of vacuum to unwind and wind a sheet substrate, the equipment performing the unwinding and winding of the sheet substrate is under atmospheric pressure, so the differential exhaust system needs to be able to handle a large differential pressure. For this reason, conventional differential exhaust systems have had to either provide many depressurization chambers or connect multiple differential exhaust systems in series to adjust the differential pressure, which has resulted in the unavoidable problem of increasing the size of the equipment.

[0008] The present invention aims to address these circumstances. Specifically, the objectives of the present invention are to improve the differential adjustment function of the differential exhaust system so that it can perform rapid and highly accurate differential adjustment in response to changes in the pressure setting in the vacuum chamber where vacuum processing is performed, and to enable space saving of the equipment even when dealing with large differential pressures.

[0009] To solve these problems, the present invention has the following configuration: A differential exhaust device connected to a vacuum chamber that performs vacuum processing on a sheet substrate and transports the sheet substrate while performing differential exhaust, comprising: a plurality of depressurization chambers arranged along the transport direction of the sheet substrate and capable of independently depressurizing and exhausting; a plurality of low-conductance flow channels arranged between two adjacent depressurization chambers and having a gap through which the sheet substrate can be transported; and a gap adjustment unit provided in each of the low-conductance flow channels for adjusting the gap with the sheet substrate.

[0010] An explanatory diagram showing an example configuration of a vacuum processing apparatus using a differential exhaust system. An explanatory diagram showing an example configuration of a differential exhaust system (first example). An explanatory diagram showing an example configuration of a differential exhaust system (second example). A plan view of a differential adjustment component (first example). A cross-sectional view of the differential adjustment component shown in Figure 4. A modified cross-sectional view of the differential adjustment component shown in Figure 4. A plan view of a differential adjustment component (second example). An explanatory diagram showing an example configuration of a differential exhaust system (third example). An explanatory diagram showing an example configuration of a differential exhaust system (fourth example). An explanatory diagram showing an embodiment of the differential exhaust system. A cross-sectional view of a differential adjustment component according to the embodiment.

[0011] Embodiments of the present invention will now be described with reference to the drawings. In the following description, the same reference numerals in different figures indicate parts with the same function, and redundant explanations in each figure will be omitted as appropriate.

[0012] Figure 1 shows an example configuration of a vacuum processing apparatus to which a differential pumping system is applied. As shown in the figure, one end of each of the differential pumping systems 1 and 2 is connected to the vacuum chamber 101 of the vacuum processing apparatus 100, and the sheet substrate Sb is transported while performing differential pumping. The vacuum processing apparatus 100 is an apparatus that performs vacuum processing on the sheet substrate Sb, such as film deposition by vacuum deposition or sputtering, or drying and cooling, and is equipped with a vacuum chamber 101 whose internal state is set to a vacuum state and temperature state suitable for processing. Inside the vacuum chamber 101, equipment for performing various processing (not shown) is provided, as well as transport rolls (not shown) for roll-to-roll transport of the sheet substrate Sb.

[0013] In the example shown in Figure 1, an atmospheric pressure chamber U1 is provided on the input side of the differential exhaust system 1, and an atmospheric pressure chamber U2 is provided on the output side of the differential exhaust system 2. An unwinding device for unwinding untreated sheet substrate Sb is provided in atmospheric pressure chamber U1, and an unwinding shaft 102 is installed therein. In addition, a winding device for winding treated sheet substrate Sb is provided in atmospheric pressure chamber U2, and a winding shaft 103 is installed therein.

[0014] The sheet substrate Sb is drawn out from the atmospheric pressure chamber U1 where unwinding takes place and transported by the differential pumping device 1 into the vacuum chamber 101 of the vacuum processing device 100. After processing there, the sheet substrate Sb is drawn out by the differential pumping device 2 and transported to the atmospheric pressure chamber U2 where winding takes place. The replacement of the sheet substrate Sb (roll replacement) is performed under atmospheric pressure, with the attachment of the roll to the unwinding shaft 102 and the removal of the roll from the winding shaft 103 being carried out under atmospheric pressure.

[0015] In the example shown in Figure 1, differential pumping system 1 is installed between atmospheric pressure chamber U1 and vacuum processing apparatus 100, and differential pumping system 2 is installed between atmospheric pressure chamber U2 and vacuum processing apparatus 100. Here, differential pumping system 1 and differential pumping system 2 are symmetrical. In the following description, only the configuration of differential pumping system 1 will be described, and the configuration of differential pumping system 2, which can be obtained by reversing it left and right, will not be described again.

[0016] The differential pumping system 1, as a basic configuration, includes a plurality of reduced-pressure spaces arranged along the conveying direction of the sheet substrate Sb, and low-conductance channels connecting these reduced-pressure spaces. These reduced-pressure spaces and the plurality of low-conductance channels form the conveying path for the sheet substrate Sb. In the example shown in Figure 1, one end of the differential pumping system 1 is connected to the vacuum chamber 101, and the other end is connected to the atmospheric pressure chamber U1. Therefore, the plurality of reduced-pressure spaces are set to a pressure close to the vacuum pressure in the space closest to the vacuum chamber 101, and are gradually set to a pressure close to atmospheric pressure as they approach the atmospheric pressure chamber U1.

[0017] As shown in Figure 2, the differential exhaust system 1 includes a plurality of depressurization chambers 11 (11A, 11B, 11C) that can be independently depressurized and exhausted, and a plurality of low-conductance flow channels 12 (12A, 12B) are arranged between two adjacent depressurization chambers 11. More specifically, a low-conductance flow channel 12A is provided between depressurization chamber 11A and depressurization chamber 11B to connect them, and a low-conductance flow channel 12B is provided between depressurization chamber 11B and depressurization chamber 11C to connect them.

[0018] The depressurization chambers 11 (11A, 11B, 11C) are formed within the housing 10, and each is provided with an exhaust port Ep. By individually depressurizing and exhausting air from each exhaust port Ep, the pressure in each depressurization chamber 11 is set independently. The depressurization chamber 11C, which is closest to the vacuum chamber 101, is set to the lowest pressure, the depressurization chamber 11A, which is closest to the atmospheric pressure chamber U1, is set to the highest pressure, and the intermediate depressurization chamber 11B is set to an intermediate pressure between depressurization chambers 11A and 11C.

[0019] Furthermore, the depressurization chambers 11 (11A, 11B, 11C) are arranged along the transport direction of the sheet substrate Sb, and together with the low-conductance flow channels 12 (12A, 12B) formed between them, they form a transport path for the sheet substrate Sb. Each of the depressurization chambers 11 (11A, 11B, 11C) is provided with a transport roller R for transporting the sheet substrate Sb. The sheet substrate Sb enters the differential exhaust device 1 from the inlet Et connected to depressurization chamber 11A, and enters the vacuum chamber 101 through the connecting port Cp connected to depressurization chamber 11C.

[0020] The low-conductance flow paths 12 (12A, 12B) in the differential pumping system 1 have gaps that allow for the transport of the sheet substrate Sb while suppressing the flow of gas between adjacent depressurization chambers 11. By connecting adjacent depressurization chambers 11 with the low-conductance flow paths 12, each depressurization chamber 11 can be independently pressure-regulated, and the differential pumping performed in each depressurization chamber 11 can suppress contamination of the space connected by the differential pumping system 1 (vacuum chamber 101 and atmospheric pressure chamber U1).

[0021] Furthermore, the differential exhaust system 1 is equipped with a gap adjustment unit 20 in each of the multiple low-conductance flow paths 12 (12A, 12B) to adjust the gap between the flow path surface 20A of the low-conductance flow path 12 (12A, 12B) and the sheet substrate Sb, and this adjustment can be performed manually or automatically using a servo motor or the like.

[0022] By adjusting the gap between the low-conductance flow channels 12 (12A, 12B), the flow rate of gas flowing between adjacent depressurization chambers 11 can be adjusted, and the differential pressure between the depressurization chambers 11 can be finely adjusted. Furthermore, by properly adjusting the distance between the flow channel surface 20A and the sheet substrate Sb, the gap between the low-conductance flow channels 12 (12A, 12B) can be properly set while avoiding contact between the sheet substrate Sb and the flow channel surface 20A.

[0023] The gap adjustment unit 20 includes a gap adjustment unit 20U, which comprises a differential adjustment component 21 having a flow channel surface 20A of a low-conductance flow channel 12 (12A, 12B) on one surface. The gap adjustment unit 20U includes a moving mechanism for moving the flow channel surface 20A in a direction perpendicular to the conveying direction of the sheet substrate Sb. In the illustrated example, the differential adjustment component 21, which has a flow channel surface 20A facing into the low-conductance flow channel 12 (12A, 12B) formed on its surface, is moved perpendicular to the plane of the sheet substrate Sb, thereby moving the flow channel surface 20A closer to or further away from one side of the sheet substrate Sb.

[0024] In the illustrated example, the mechanism for moving the differential adjustment component 21 is a manual mechanism. When the handle 22 is rotated manually, the adjustment shaft 23 moves perpendicular to the transport path of the sheet substrate Sb, and the differential adjustment component 21, which is fixed to the tip of the adjustment shaft 23, moves along with it.

[0025] As shown in Figure 3, the gap adjustment unit 20U can be installed on both the front and back sides of the sheet substrate Sb. In the illustrated example, a pair of differential adjustment components 21 are arranged in one low-conductance flow path 12 such that the flow path surfaces 20A face each other with the sheet substrate Sb in between, and a moving mechanism is provided to move each differential adjustment component 21. In this example, the low-conductance flow path 12 is formed between the facing flow path surfaces 20A. By providing the gap adjustment unit 20U on both the front and back sides of the sheet substrate Sb in this way, the gap adjustment range can be doubled, and the adjustment range for differential pressure can be broadened.

[0026] The differential adjustment component 21 in the gap adjustment unit 20U can be made up of, for example, a single rectangular parallelepiped or a combined component, with the widest rectangular surface serving as the flow path surface 20A. The flow path surface 20A of the differential adjustment component 21 can be provided with irregularities or other features that create resistance to the gas flow in order to further lower the conductance of the low-conductance flow path 12.

[0027] Figures 4 to 6 show examples of the shape of recesses provided on the flow path surface 20A of the differential adjustment component 21 (the X, Y, and Z directions in the figures indicate the direction of transport of the sheet substrate Sb, the Y direction the width direction of the flow path perpendicular to the aforementioned transport direction, and the Z direction the gap direction of the flow path perpendicular to the aforementioned transport direction). In this example, multiple recesses 21P are provided in parallel in a direction perpendicular to the transport direction of the sheet substrate Sb (Y direction in the figure), and one recess 21P is provided continuously along the transport direction of the sheet substrate Sb (X direction in the figure). The total width or cross-sectional area of ​​the recesses 21P in the direction perpendicular to the transport direction of the sheet substrate Sb (Y direction in the figure) gradually decreases toward the adjacent low-pressure side depressurization chamber 11.

[0028] Specifically, when the differential adjustment component 21 is installed in the low-conductance flow path 12A, the groove width W1 in the cross section on the depressurization chamber 11A side (A1-A1 cross section) and the groove width W2 in the cross section on the depressurization chamber 11B side (B1-B1 cross section) are such that W1 > W2. Assuming that the groove depth d of the recess 21P is constant, the cross-sectional area of ​​the recess 21P in the A1-A1 cross section (W1・d) and the cross-sectional area of ​​the recess 21P in the B1-B1 cross section (W2・d) are such that W1・d > W2・d. In the illustrated example, the multiple parallel recesses 21P are arranged at a constant interval S along the Y direction shown in the illustration. Furthermore, the cross-sectional shape of the recess 21P may be a rectangular cross-section as shown in Figure 5, or it may be an inverted trapezoidal cross-section with a taper on the groove wall surface as shown in Figure 6.

[0029] Figure 7 shows another example of a recess provided on the flow path surface 20A of the differential adjustment component 21 (the directions X, Y, and Z are the same as in Figures 4 to 6). In this example, a recess 21P with a width W10 along the direction Y is formed diagonally toward the direction X, and the recess 21P crosses on the low-pressure side of the flow path surface 20A, forming a V-shape in plan view. In the cross section on the depressurization chamber 11A side (A2-A2 cross section), the total groove width of this recess 21P is W10 × 6, and in the cross section on the depressurization chamber 11B side (B2-B2 cross section), the total groove width is W20 × 3, and the relationship between the two is W10 × 6 > W20 × 3. By providing a recess 21P of this form on the flow path surface 20A, the flow of gas toward the low-pressure side can be suppressed, and the conductance performance of the low-conductance flow path 12 can be further reduced.

[0030] Figure 8 shows another configuration example of the differential exhaust system 1. In the illustrated example, the internal volume of the multiple depressurization chambers 11 (11A, 11B, 11C) gradually decreases as they approach the vacuum chamber 101. That is, if the internal volume of depressurization chamber 11A is V1, the internal volume of depressurization chamber 11B is V2, and the internal volume of depressurization chamber 11C is V3, then V1 > V2 > V3. With this configuration, by making the internal volume of depressurization chamber 11C, which is closer to the vacuum chamber 101 where the set pressure needs to be lower, smaller, the differential pressure between the depressurization chambers 11 can be adjusted quickly. Furthermore, as shown in the figure, by providing a venturi structure Vt toward the low-pressure side of each depressurization chamber 11, differential pressure adjustment can be made even easier.

[0031] Figure 9 shows another configuration example of the differential exhaust system 1, in which the arrangement direction of the depressurization chambers 11 is changed. In this example, the conveying direction of the sheet substrate Sb and the arrangement direction of the depressurization chambers 11 (11A, 11B, 11C) within the differential exhaust system 1 are arranged along the vertical direction perpendicular to the device mounting surface Bs. In this case, if the device mounting surface Bs is a horizontal plane, the conveying direction of the sheet substrate Sb and the arrangement direction of the depressurization chambers 11 (11A, 11B, 11C) become vertical. By adopting this arrangement configuration, the length dimension of the differential exhaust system 1 along the device mounting surface Bs can be shortened, and the vacuum processing apparatus 100 and the atmospheric pressure chamber U1 can be placed in close proximity, thereby making efficient use of the overall installation space of the device.

[0032] A more specific embodiment of the differential exhaust system 1 is described below. As shown in Figure 10, in the differential exhaust system 1 according to this embodiment, the intermediate depressurization chamber 11B is positioned lower than the positions of the high-pressure side depressurization chamber 11A and the low-pressure side depressurization chamber 11C, thereby providing a roller arrangement angle θ for the transport rollers R arranged in each of the depressurization chambers 11 (11A, 11B, 11C). As a result, the transport path of the sheet substrate Sb in a side view is V-shaped, and the transport direction of the sheet substrate Sb in the low-conductance flow path 12 where the gap adjustment section 20 is provided is inclined with respect to the horizontal. Such a differential exhaust system 1 can save space in the vertical and horizontal directions while ensuring sufficient length of the low-conductance flow path 12 where the gap adjustment section 20 is provided.

[0033] To achieve this arrangement of pressure-reducing chambers 11 (11A, 11B, 11C), the differential exhaust device 1 forms two upward-facing openings in the U-shaped housing 10, and one downward-facing opening between them. The openings of each space are then closed with a cover 13 having an exhaust port Ep, thereby creating three pressure-reducing chambers 11 (11A, 11B, 11C). Spaces 10T for forming low-conductance flow paths 12 are formed between pressure-reducing chambers 11A and 11B, and between pressure-reducing chambers 11B and 11C in the housing 10. A gap adjustment unit 20U is detachably installed in space 10T of the housing 10.

[0034] As described above, the gap adjustment unit 20U includes a differential adjustment component 21 as a component. By installing this gap adjustment unit 20U in the space 10T, a low-conductance flow path 12 is formed on the flow path surface 20A of the differential adjustment component 21. The gap adjustment unit 20U is a mechanical unit comprising a moving mechanism 24 that moves the differential adjustment component 21 closer to or further away from the sheet substrate Sb in the low-conductance flow path 12, and a drive unit (actuator) 25 for driving the moving mechanism 24.

[0035] A seal ring (O-ring) 26 is positioned around the differential adjustment component 21 (see Figure 11). The seal ring 26 ensures airtightness between the inner surface of the space 10T of the housing 10 and the side surface of the differential adjustment component 21, thereby suppressing leakage of the low-conductance flow path 12. The leak suppression effect can be further enhanced by using a double-layered seal ring 26.

[0036] The differential exhaust system 1 according to the embodiment shown in Figure 10 includes a control unit 30. The control unit 30 automatically controls the adjustment operation of the gap adjustment unit 20U. Based on the output of a sensor unit 40 provided on the differential adjustment component 21, the control unit 30 controls the drive unit 25 to automatically adjust the gap between the flow path surface 20A in the differential adjustment component 21 and the sheet substrate Sb in the low-conductance flow path 12.

[0037] Figure 11 illustrates the sensor unit 40 provided on the differential adjustment component 21. One of the sensor units 40 is a gap detection sensor 41, which is composed of a laser displacement meter or the like. The gap detection sensor 41 emits laser light from a sensor window 44 through a quartz glass 43 provided in the detection space 42, and receives the light reflected by the sheet substrate Sb in the low-conductance flow path 12, thereby measuring the gap between the flow path surface 20A of the differential adjustment component 21 and the sheet substrate Sb. At this time, the quartz glass 43 provided in the detection space 42 is installed airtightly via a seal ring 43A. This prevents the low-conductance flow path 12 from leaking through the detection space 42.

[0038] In addition to the gap detection sensor 41 mentioned above, the sensor unit 40 can also be provided with a parallelism detection sensor 45. The parallelism detection sensor 45 is distributed in multiple locations on the flow channel surface 20A to detect the parallelism between the flow channel surface 20A and the surface of the sheet substrate Sb. Here, by arranging multiple parallelism detection sensors 45 on the flow channel surface 20A along the X and Y directions shown in the figure, the inclination of the differential adjustment component 21 is adjusted so that the flow channel surface 20A is parallel to the surface of the sheet substrate Sb.

[0039] As shown in Figure 10, the control unit 30 can control multiple gap adjustment units 20U collectively. In this case, the control unit 30 can control the drive unit 25 independently or synchronously for the multiple gap adjustment units 20U. When controlling multiple gap adjustment units 20U, for example, the multiple gap adjustment units 20U can be controlled synchronously for the movement of the large differential adjustment component 21, and when performing control related to fine differential adjustment, the individual differential adjustment components 21 of the multiple gap adjustment units 20U can be controlled independently, enabling efficient differential adjustment.

[0040] The control unit 30 receives input from a pressure gauge (not shown) that measures the pressure in each depressurization chamber 11, as well as from a vacuum gauge (not shown) that measures the vacuum level of the vacuum chamber 101. As a result, if the vacuum level of the vacuum chamber 101 changes, the control unit 30 detects this and automatically controls the differential adjustment by controlling the gap adjustment unit 20U so that the pressure in each depressurization chamber 11 becomes the set pressure.

[0041] Furthermore, a sheet detection sensor 46, as shown in Figure 10, can be provided in the low-conductance flow channels 12 (12A, 12B) on the side opposite to the flow channel surface 20A of the differential adjustment component 21. The sheet detection sensor 46 is one of the sensor units 40 and detects the conveying state of the sheet and transmits a detection signal to the control unit 30. The control unit 30 can then control the differential adjustment according to the conveying state of the sheet substrate Sb.

[0042] In the above description, an example was given in which a differential pumping device 1(2) is installed between the vacuum processing device 100 and the atmospheric pressure chamber U1 (U2). However, the differential pumping device 1(2) is not limited to the above example and can be installed between adjacent vacuum chambers in multiple vacuum processing devices with different vacuum states (reduced pressure states). In this case, the pressure settings of the multiple reduced pressure chambers 11 in the differential pumping device 1(2) are set according to the differential pressure of the adjacent vacuum chambers, and the differential pressure is adjusted so that the pressure increases in stages from the low-pressure side to the high-pressure side.

[0043] Although embodiments of the present invention have been described in detail above with reference to the drawings, the specific configurations are not limited to these embodiments, and any design changes, etc., that do not depart from the gist of the present invention are also included. Furthermore, the above-described embodiments can be combined by utilizing each other's technologies, as long as there are no particular contradictions or problems in their purpose and configuration.

[0044] 1, 2: Differential exhaust system 100: Vacuum processing device 101: Vacuum chamber 102: Unwinding shaft 103: Rewinding shaft U1, U2: Atmospheric pressure chamber Sb: Sheet substrate 10: Housing 11 (11A, 11B, 11C): Reduced pressure chamber 10T: Space 12 (12A, 12B): Low conductance flow path 13: Cover 20: Gap adjustment section 20A: Flow path surface 20U: Gap adjustment unit 21: Differential adjustment component 21P: Recess 22: Handle 23: Adjustment shaft 24: Moving mechanism 25: Drive unit 26: Seal ring 30: Control unit 40: Sensor section 41: Gap detection sensor 42: Detection space 43: Quartz glass 44: Sensor window 45: Parallelism detection sensor 46: Sheet detection sensor Ep: Exhaust port R: Conveyor roller Et: Inlet Cp: Connecting port Vt: Venturi structure

Claims

1. A differential exhaust device connected to a vacuum chamber for performing vacuum processing on a sheet substrate, which transports the sheet substrate while performing differential exhaust, comprising: a plurality of depressurization chambers arranged along the transport direction of the sheet substrate and capable of independently depressurizing and exhausting; a plurality of low-conductance flow channels arranged between two adjacent depressurization chambers and having a gap through which the sheet substrate can be transported; and a gap adjustment section provided in each of the low-conductance flow channels for adjusting the gap with the sheet substrate, wherein the gap adjustment section comprises a gap adjustment unit that moves the flow channel surface of the low-conductance flow channel closer to or further away from the sheet substrate, the gap adjustment unit comprises a differential adjustment component having the flow channel surface on one surface, and a moving mechanism that moves the differential adjustment component in a direction perpendicular to the transport direction of the sheet substrate, the gap adjustment unit is detachably mounted on a housing provided with the depressurization chambers, and a sealing ring is arranged around the differential adjustment component to ensure airtightness with the housing.

2. The differential exhaust device according to claim 1, wherein each of the depressurization chambers is provided with a conveying roller for conveying the sheet substrate, and the conveying rollers are positioned at an angle such that the conveying direction of the sheet substrate in the low-conductance flow path is inclined with respect to the horizontal.

3. A differential exhaust device connected to a vacuum chamber for performing vacuum processing on a sheet substrate, which transports the sheet substrate while performing differential exhaust, comprising: a plurality of depressurization chambers arranged along the transport direction of the sheet substrate and capable of independently depressurizing and exhausting; a plurality of low-conductance flow channels arranged between two adjacent depressurization chambers and having a gap through which the sheet substrate can be transported; and a gap adjustment unit provided in each of the low-conductance flow channels for adjusting the gap with the sheet substrate, wherein the gap adjustment unit comprises a gap adjustment unit that moves the flow channel surface of the low-conductance flow channel closer to or further away from the sheet substrate, and the flow channel surface is provided with a plurality of parallel recesses in a direction perpendicular to the transport direction, the recesses are continuous along the transport direction, and the sum of the width or cross-sectional area in the direction perpendicular to the transport direction gradually decreases toward the depressurization chamber on the low-pressure side, the differential exhaust device.

4. A differential exhaust system connected to a vacuum chamber for performing vacuum processing on a sheet substrate, which transports the sheet substrate while performing differential exhaust, comprising: a plurality of depressurization chambers arranged along the transport direction of the sheet substrate and capable of independently depressurizing and exhausting; a plurality of low-conductance flow channels arranged between two adjacent depressurization chambers and having a gap through which the sheet substrate can be transported; and a gap adjustment unit provided in each of the low-conductance flow channels for adjusting the gap with the sheet substrate, wherein the internal volume of the plurality of depressurization chambers gradually decreases as they approach the vacuum chamber.

5. The differential exhaust device according to claim 1, wherein the gap adjustment unit is provided on both the front and back sides of the sheet substrate.

6. The differential exhaust device according to claim 1, wherein the gap adjustment unit comprises a drive unit for driving the moving mechanism, and a control unit for controlling the drive unit based on the output of a sensor unit provided on the differential adjustment component.

7. The differential exhaust device according to claim 6, wherein the sensor units are distributed in a plurality on the flow path surface to detect the degree of parallelism between the flow path surface and the surface of the sheet substrate.

8. The differential exhaust system according to claim 6, wherein the control unit controls the drive unit independently or synchronously with respect to a plurality of gap adjustment units.

9. A differential exhaust system connected to a vacuum chamber for performing vacuum processing on a sheet substrate, which transports the sheet substrate while performing differential exhaust, comprising: a plurality of depressurization chambers arranged along the transport direction of the sheet substrate and capable of independently depressurizing and exhausting; a plurality of low-conductance flow channels arranged between two adjacent depressurization chambers and having a gap through which the sheet substrate can be transported; and a gap adjustment unit provided in each of the low-conductance flow channels for adjusting the gap with the sheet substrate, wherein the transport direction and the arrangement direction of the depressurization chambers are arranged along a vertical direction perpendicular to the installation surface of the device.

Images