Gas introduction device

Abstract

The present invention provides a gas introduction device that simplifies the structure and control while mitigating the rapid pressure increase in the depressurized chamber when it is opened to the atmosphere. [Solution] A gas introduction device 10 is attached to the atmospheric intake side of an atmospheric release valve 6 that opens a depressurization chamber 2, which is reduced to a pressure lower than atmospheric pressure, to the atmosphere, and comprises a valve body 18 that opens and closes the atmospheric intake side of the atmospheric release valve, a small amount of gas introduction section 14 whose opening area is smaller than the opening area of ​​the valve body in the fully open position and which allows gas to be introduced regardless of the position of the valve body, and a biasing mechanism 20 that biases the valve body, which is in the closed position due to the negative pressure of the depressurization chamber when the atmospheric release valve is opened, toward the fully open position.

Description

Technical Field

[0001] The present disclosure relates to a gas introduction device attached to the air intake side of an atmospheric release valve.

Background Art

[0002] Conventionally, devices for processing or machining various objects to be processed or machined in a decompression chamber (vacuum chamber) are known. For example, Patent Document 1 below discloses an atmospheric release device that supplies gas when the atmosphere is released into a load lock chamber serving as a vacuum chamber for processing a semiconductor wafer as a workpiece. This atmospheric release device includes a main gas supply system in which a main opening / closing valve and a flow control valve are provided in a gas introduction passage, a release communication passage connected to the gas introduction passage and provided with an auxiliary opening valve, and a control unit that controls the opening and closing of each valve. In this atmospheric release device, when atmospheric release is started, the main opening / closing valve is opened according to a command from the control unit, and a start trigger is given to the flow control valve so that the valve opening degree of the flow control valve linearly changes from zero to the fully open state. Further, in the atmospheric release device, when the flow control valve is in the fully open state, the pressure in the load lock chamber rapidly rises to a predetermined pressure value and a predetermined time has elapsed, the main opening / closing valve is closed and at the same time the auxiliary opening / closing valve is opened.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the atmospheric release device as described in Patent Document 1 above, it is necessary to provide three valves, and when the atmosphere in the vacuum chamber (load lock chamber) is released, it is necessary to control these three valves by a control unit, which may lead to structural and control complexity.

[0005] This disclosure has been made in view of the above circumstances and aims to provide a gas introduction device that can simplify the structure and control while mitigating the rapid pressure rise in the depressurized chamber when it is opened to the atmosphere. [Means for solving the problem]

[0006] To achieve the above objective, the gas introduction device configuration 1 according to the present disclosure is a gas introduction device attached to the atmospheric intake side of an atmospheric release valve that opens a depressurization chamber, which is depressurized to a pressure lower than atmospheric pressure, to the atmosphere, and is characterized by comprising: a valve body that opens and closes the atmospheric intake side of the atmospheric release valve; a small amount gas introduction section whose opening area is smaller than the opening area of ​​the valve body at the fully open position, thereby enabling gas introduction regardless of the position of the valve body; and a biasing mechanism that biases the valve body, which is in the closed position due to the negative pressure of the depressurization chamber when the atmospheric release valve is opened, toward the fully open position.

[0007] The following description of embodiments reveals that the gas introduction device according to this disclosure may have the following dependent configurations. <Configuration 2> In configuration 1, the device may include a cylindrical body having a mounting portion at one end that is attached to the mounting portion on the atmospheric intake side of the atmospheric release valve so as to communicate with the atmospheric intake side opening of the atmospheric release valve, and an opening at the other end that is opened and closed on the valve body. <Structure 3> In configuration 2, the small gas introduction section may be provided in the cylindrical body. <Structure 4> In any one of configurations 1 to 3, the small gas introduction section may be provided with a flow rate adjustment section that allows for increasing or decreasing the opening area. <Composition 5> In any one of configurations 1 to 4, the biasing mechanism may be provided with a biasing force adjustment unit that adjusts the biasing force of the biasing member that biases the valve body toward the fully open position. <Composition 6> In any one of configurations 1 to 5, at least one of the valve body and the peripheral edge of the opening opened and closed by the valve body may be provided with an opening area variable portion that makes the opening area of ​​the valve body smaller than that of the fully open position during the opening process. [Effects of the Invention]

[0008] The gas introduction device described in this disclosure, with the configuration described above, can mitigate the rapid pressure rise in the depressurized chamber when open to the atmosphere, while also simplifying its structure and control. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic plan view illustrating an example of a vacuum treatment apparatus, including an example of a gas introduction device according to one embodiment of the present disclosure. [Figure 2] (a) to (c) are schematic longitudinal cross-sectional views of a partial fracture, corresponding to the view along the line XX in Figure 1. [Figure 3] This is a schematic graph illustrating the change in gas flow velocity as it passes through the downstream section of the gas introduction device. [Figure 4] (a) and (b) are schematic cross-sectional views of a modified example of the gas introduction device, with a partial fracture, corresponding to Figure 2. [Figure 5] (a) and (b) are schematic cross-sectional views of a partially fractured section illustrating an example of the gas introduction device. [Figure 6] This is a schematic graph illustrating the change in gas flow velocity as it passes through the downstream section of the gas introduction device. [Figure 7] (a) to (c) are schematic cross-sectional views of a partially fractured section illustrating other variations of the same gas introduction device, corresponding to Figure 2. [Figure 8] This is a schematic graph illustrating the change in gas flow velocity as it passes through the downstream section of the gas introduction device. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIGS. 1 to 8 schematically show an example of a gas introduction device according to this embodiment, an example of a vacuum processing device including the same, a modified example of the gas introduction device, and the transition of the flow velocity of the gas passing through the downstream part of the gas introduction device in each example.

[0011] As shown in FIG. 1, the gas introduction device 10 according to this embodiment is attached to the atmospheric intake side of an atmospheric release valve 6 that opens the decompression chamber 2 decompressed to a pressure lower than atmospheric pressure to the atmosphere. This gas introduction device 10 may be provided in a vacuum processing device 1 that includes the decompression chamber 2 and performs various processes and machining on a processing target or a machining target (hereinafter referred to as a processing target) under reduced pressure in the decompression chamber 2. Such a vacuum processing device 1 may be provided with a mixed liquid discharge machine that mixes and injects a first liquid (for example, a main agent) and a second liquid (for example, a curing agent) into a processing target such as an electronic device, an electrical appliance, or various parts arranged in the decompression chamber 2. In this case, the decompression chamber 2 may be provided with a transport mechanism for transporting the processing target in and out, a transport inlet and a transport outlet of the decompression chamber 2, and a shutter for sealing these in an openable and closable manner.

[0012] A vacuum pump 3 for decompressing the inside of the decompression chamber 2 is connected to the decompression chamber 2 via a vacuum pipeline. A vacuum valve 4 for opening and closing the vacuum pipeline is provided in the vacuum pipeline. Further, a pressure gauge 5 for measuring the pressure inside the decompression chamber 2 is provided in the decompression chamber 2. The decompression chamber 2 may be configured to be decompressed to a pressure lower than atmospheric pressure, for example, may be configured as a vacuum chamber (vacuum chamber) decompressed to a substantially vacuum state of about 1000 Pa to 1500 Pa (absolute pressure). An atmospheric release valve 6 is connected to the decompression chamber 2 so as to communicate with the inside of the decompression chamber 2. This atmospheric release valve 6 may be an electromagnetic valve having a valve body that opens and closes a cylindrical portion whose one end is connected to the decompression chamber 2 so as to open toward the inside of the decompression chamber 2 and whose other end side is the atmospheric intake side.

[0013] The pressure reduction processing apparatus 1 may be provided with a control unit 9 for controlling each part. The control unit 9 may be connected to the drive unit of the above-described conveyance mechanism, the drive unit of the shutter, the mixed liquid discharger, the vacuum pump 3, the vacuum valve 4, the pressure gauge 5, the atmosphere release valve 6, etc. via appropriate signal lines or the like. This control unit 9 includes a control circuit such as a CPU (Central Processing Unit), an input unit, an output unit, etc., and may be a PLC (Programmable Logic Controller) or the like that executes the basic operations and the like described later. A display operation unit for making settings, inputs, and displays such as various settings may be provided on the control panel including this control unit 9. Further, the control panel stores various programs such as setting conditions and input values set and input by operating the display operation unit, control programs for executing the basic operations and the like described later, various preset operation conditions, various data tables, etc., and a storage unit composed of various memories such as ROM and RAM may be provided.

[0014] In this pressure reduction processing apparatus 1, each part may be controlled by the control unit 9 to execute the following basic operations. First, the object to be processed is carried into the pressure reduction chamber 2 by the conveyance mechanism through the carry-in port of the pressure reduction chamber 2, the carry-in port is sealed by the shutter, and the pressure reduction chamber 2 is depressurized by the vacuum pump 3. At this time, the vacuum pump 3 and the vacuum valve 4 may be controlled based on the measured value of the pressure gauge 5. Then, when the pressure reduction chamber 2 reaches a predetermined pressure reduction state (vacuum state), the drive of the mixed liquid discharger is controlled to inject the mixed liquid into the object to be processed. When the injection is completed, the atmosphere release valve 6 is opened to release the pressure in the pressure reduction chamber 2 to the atmosphere (break the vacuum). Then, when the inside of the pressure reduction chamber 2 reaches atmospheric pressure (or a pressure that does not adversely affect the object to be processed), the shutter at the carry-out port may be opened to carry out the object to be processed. The basic operation of the pressure reduction processing apparatus 1 is not limited to such an operation, and may be in various other modes. Further, the pressure reduction processing apparatus 1 is not limited to an apparatus that injects such a mixed liquid, and may be an apparatus that performs other processes or processing on the object to be processed.

[0015] As described above, when the depressurization chamber 2 is opened to the atmosphere, if a relatively large amount of gas is introduced into the depressurization chamber 2 from the initial stage of opening to the atmosphere, the pressure difference between the depressurization chamber 2 and atmospheric pressure will be large, causing the gas to be rapidly introduced into the depressurization chamber 2 and the pressure to rise rapidly. As a result, there are concerns that the mixed liquid injected into the object to be treated may ripple or adhere to other parts, dust and other particles may be stirred up and adhere to the object, and the mixed liquid remaining at the nozzle tip of the mixed liquid discharger may be scattered. On the other hand, if a throttle valve such as a needle valve is provided on the atmospheric intake side of the atmospheric release valve 6, and a small amount of gas is introduced when the depressurization chamber 2 is opened to the atmosphere, the time required for the depressurization chamber 2 to reach atmospheric pressure tends to be prolonged. To mitigate the rapid pressure increase in the decompression chamber 2 when the valve is opened to the atmosphere, and to shorten the time required for the decompression chamber 2 to reach atmospheric pressure, a gas introduction device 10 is installed on the atmospheric intake side of the atmospheric release valve 6.

[0016] The gas introduction device 10 includes a valve body 18 that opens and closes the atmospheric intake side of the atmospheric release valve 6, a small gas introduction section 14 whose opening area is smaller than the opening area of ​​the valve body 18 in the fully open position, allowing gas to be introduced regardless of the position of the valve body 18, and a biasing mechanism 20 that biases the valve body 18, which is in the closed position due to the negative pressure in the decompression chamber 2 when the atmospheric release valve 6 is opened, toward the fully open position. With this configuration, when the atmospheric release valve 6 that opens the decompression chamber 2 to the atmosphere is opened, the valve body 18 is drawn in by the negative pressure in the decompression chamber 2 against the biasing force of the biasing mechanism 20 and moves to the closed position, but a small amount of gas is introduced into the decompression chamber 2 via the small gas introduction section 14. This makes it possible to mitigate the rapid pressure rise in the decompression chamber 2 when it is opened to the atmosphere. In other words, even when the valve body 18, which has a large opening area in the fully open position, is in the closed position, a small amount of gas is introduced into the decompression chamber 2 via the small gas introduction section 14. As a result, the adverse effects described above, such as those caused by a sudden increase in pressure, become less likely to occur on the processed or modified objects within the reduced pressure chamber 2.

[0017] Furthermore, as the small amount of gas introduced through the small amount gas introduction section 14 continues and the pressure inside the depressurization chamber 2 gradually increases, reducing the pressure difference between the inside and outside of the depressurization chamber 2, the valve body 18 is displaced to the open side by the biasing mechanism 20, increasing the amount of gas introduced. This shortens the time required to bring the inside of the depressurization chamber 2 to atmospheric pressure. As a result, the cycle time when processing or manufacturing the object to be processed inside the depressurization chamber 2 can be shortened. In addition, since the gas introduction device 10 is attached to the atmospheric intake side of the atmospheric release valve 6 that opens the depressurization chamber 2 to the atmosphere, and its valve body 18 is closed and opened by the negative pressure in the depressurization chamber 2 and the biasing mechanism 20, the structure and control can be simplified compared to a configuration in which multiple valves are provided and the opening and closing of these valves are controlled by a control unit.

[0018] As shown in Figure 2, the gas introduction device 10 comprises a cylindrical body 11 with a mounting portion 12 at one end that connects to the atmospheric intake opening 7 of the atmospheric release valve 6 and is attached to the atmospheric intake side mounting portion 8 of the atmospheric release valve 6, and an opening 13 at the other end that is opened and closed by the valve body 18. With this configuration, the gas introduction device 10 can be attached to the atmospheric release valve 6 by attaching the mounting portion 12 of the cylindrical body 11 to the atmospheric intake side mounting portion 8 of the atmospheric release valve 6. Furthermore, by configuring the diameter of the cylindrical body 11 and the mounting portion 12 to match the diameter of the atmospheric intake side opening 7 and the mounting portion 8 of an existing (general-purpose) atmospheric release valve 6, it is possible to easily add the gas introduction device 10 as an option to a device having an atmospheric release valve 6.

[0019] The cylindrical body 11 is substantially cylindrical in shape. The mounting portion 12 at one end of the cylindrical body 11 and the mounting portion 8 on the atmospheric intake side of the cylindrical part of the atmospheric release valve 6 are configured to be screwed together. With this configuration, the gas introduction device 10 can be easily attached to the atmospheric release valve 6 by screwing the cylindrical body 11 to the cylindrical part of the atmospheric release valve 6. In the illustrated example, a female screw groove constituting the mounting portion 8 is formed on the inner circumferential surface of the atmospheric intake side end of the cylindrical part of the atmospheric release valve 6, and a male screw groove constituting the mounting portion 12 is formed on the outer circumferential surface of one end of the cylindrical body 11. The mounting portion 8 of the atmospheric release valve 6 and the mounting portion 12 of the cylindrical body 11 are not limited to this screw-joint configuration, but may also be a suitable flange that is flange-jointed. Furthermore, the cylindrical body 11 is not limited to a substantially cylindrical shape, but may also be substantially rectangular, and not limited to a straight cylindrical shape, but may also be an elbow-shaped cylindrical shape, for example.

[0020] The small gas introduction section 14 is provided with a flow rate adjustment section 17 that allows the opening area to be increased or decreased. With this configuration, the flow rate of the gas introduced into the depressurization chamber 2 via the small gas introduction section 14 during the initial opening of the atmospheric release valve 6 can be adjusted. This makes it possible to adjust the flow rate of the gas introduced into the depressurization chamber 2 during the initial opening of the atmospheric release valve 6 so that adverse effects such as the rapid pressure increase described above are less likely to occur on the objects being processed in the depressurization chamber 2, depending on the degree of depressurization (vacuum) in the depressurization chamber 2. The small gas introduction section 14 is provided in the cylindrical body 11. With this configuration, for example, compared to a configuration in which the small gas introduction section 14 is provided in the valve body 18, adverse effects on the opening and closing of the valve body 18 can be reduced. Furthermore, even when it is difficult to provide the small gas introduction section 14, which has the flow rate adjustment section 17 as described above, in the valve body 18 due to space limitations, it can be stably provided in the cylindrical body 11.

[0021] This small-volume gas introduction section 14 is attached to the cylindrical wall of the cylindrical body 11. This small-volume gas introduction section 14 is provided with an upstream opening 15 on the upstream side in the gas introduction direction and a downstream opening 16 on the downstream side in the gas introduction direction. The upstream opening 15 may be opened to take in atmospheric air (outside air), and a pipeline for supplying an inert gas such as nitrogen-enriched gas may be connected to this upstream opening 15. The downstream opening 16 is provided to open on the inner circumferential surface of the cylindrical body 11. This downstream opening 16 is provided at an intermediate point between one end and the other end of the cylindrical body 11. In the illustrated example, an example is shown in which the downstream opening 16 is located approximately in the center in the axial direction of the cylindrical body 11, but it is not limited to this example. The flow rate adjustment section 17 may include a needle that increases or decreases the cross-sectional area (opening) of the passage between the upstream opening 15 and the downstream opening 16, or a manual operation section that adjusts the opening by moving the needle back and forth relative to the valve seat. In other words, the small gas introduction section 14 may be a manual flow rate control valve. Such a flow rate control valve may be a needle valve (throttling valve), or a speed controller (speed control valve) equipped with a check valve (non-return valve) in addition to the needle. Note that instead of providing the small gas introduction section 14 on the cylindrical body 11, it may be provided on the valve body 18 as described later.

[0022] As shown in Figure 2(b), the valve body 18 is configured to close the opening 13 of the cylindrical body 11. In the illustrated example, the valve body 18 is approximately disc-shaped with a diameter larger than the diameter of the opening 13 (the inner diameter of the other end (outer end) of the cylindrical body 11). When the valve body 18 is in the closed position, the outer peripheral end of the side of the valve body 18 facing the cylindrical body 11 (one side in the thickness direction) abuts against the end face that constitutes the peripheral edge of the opening 13 of the cylindrical body 11. On the other hand, when the valve body 18 is in the fully open position, as shown in Figure 2(a), the outer peripheral end of the side of the valve body 18 facing the end face of the cylindrical body 11 on the opening 13 side is positioned opposite. The opening area of ​​the valve body 18 in the fully open position may be understood as the lateral area of ​​the gap between the valve body 18 and the opening 13 in the fully open position. In other words, the opening area of ​​the valve body 18 in the fully open position may be understood as the value obtained by multiplying the dimension along the axial direction (axial direction of the cylindrical body 11, hereinafter the same) from the valve body 18 in the fully open position to the end face of the cylindrical body 11 on the opening 13 side by the inner diameter of the opening 13 and pi. The opening area of ​​the valve body 18 in the fully open position may also be the effective cross-sectional area. The opening area of ​​the small gas introduction section 14 described above (or the effective cross-sectional area at maximum opening if the flow rate is adjustable) should be smaller than the opening area (effective cross-sectional area) of the valve body 18 at its fully open position, and may be as small as 1 / 100 to 1 / 3 of the opening area (effective cross-sectional area) of the valve body 18 at its fully open position. The gas introduced into the cylindrical body 11 through the opening 13 when the valve body 18 is open may be atmospheric air (outside air) or an inert gas such as nitrogen-enriched gas, as described above.

[0023] The biasing mechanism 20 is provided with a biasing force adjustment unit 24 for adjusting the biasing force of the biasing member 27 that biases the valve body 18 toward the fully open position. With this configuration, the timing at which the valve body 18, which is in the closed position due to the negative pressure in the depressurization chamber 2, moves to the open position can be adjusted. As a result, the biasing force of the biasing member 27 can be adjusted according to the degree of depressurization (vacuum) in the depressurization chamber 2 so as to prevent adverse effects from a sudden pressure increase on the object being processed in the depressurization chamber 2, and to shorten the cycle time.

[0024] The biasing mechanism 20 includes a guide portion 22 that guides the valve body 18 as it is displaced axially between a closed position and a fully open position, and a holding portion 21 that holds the guide portion 22. The guide portion 22 is axial (columnar) in shape, with its axial direction aligned with the axial direction of the cylindrical body 11, and a portion of its axial direction is located inside the cylindrical body 11. This guide portion 22 is inserted through a shaft insertion hole provided in the thickness direction of the valve body 18. In other words, the valve body 18 is freely displaceable in the axial direction along the guide portion 22 inserted through its shaft insertion hole. The inner diameter of the shaft insertion hole of the valve body 18 may be slightly larger than the outer diameter of the guide portion 22 so that the valve body 18 can be smoothly displaced in the axial direction relative to the guide portion 22 and is less likely to tilt. The shaft insertion hole of the valve body 18 may also penetrate the center (central part) of the valve body 18.

[0025] As shown in Figures 1 and 2, the retaining portion 21 holds the guide portion 22 on the side of the valve body 18 opposite to the opening 13 in the thickness direction, and also functions as a stopper to prevent further displacement of the valve body 18 to the open side when it is in the fully open position. The stopper portion that functions as a stopper for the retaining portion 21 is formed to extend in the radial direction of the valve body 18, and the stopper portion is provided with a shaft insertion hole through which the guide portion 22 is inserted. The retaining portion 21 is provided with fixing pieces that extend from both ends of the stopper portion toward the cylindrical body 11 and are fixed to the cylindrical body 11. The dimensions of the fixing pieces on both sides of the retaining portion 21 along the circumferential direction (circumferential direction of the valve body 18) may be relatively small so that gas can flow smoothly when the valve body 18 is in the fully open position.

[0026] As shown in Figure 2, the biasing member 27 is a compression coil spring through which a portion extending into the cylindrical body 11 of the guide portion 22 is inserted. A flange-shaped retaining portion 23 is provided at the end of the guide portion 22 inside the cylindrical body 11 to prevent one end of the biasing member 27 from coming off. The other end of the biasing member 27 is in contact with the valve body 18. In other words, the biasing member 27 is configured to bias the valve body 18 toward the stopper portion of the holding portion 21, which is in the fully open position, relative to the retaining portion 23 of the guide portion 22. The biasing force adjustment unit 24 is configured to adjust the biasing force of the biasing member 27 by deforming the biasing member 27 between the retaining unit 23 and the valve body 18 in the expansion and contraction direction. In the illustrated example, the biasing force adjustment unit 24 includes a male screw portion 25 provided on the part of the guide unit 22 that extends in the thickness direction of the valve body 18 to a side different from the opening 13 and protrudes from the stopper portion of the holding unit 21, and a female screw portion 26 that displaces this male screw portion 25 axially relative to the holding unit 21.

[0027] In other words, if the male screw portion 25 is displaced relative to the female screw portion 26 so that the retaining portion 23 is brought closer to the stopper portion of the holding portion 21, the biasing member 27 is compressed, and the elastic force (biasing force) becomes large. On the other hand, if the male screw portion 25 is displaced relative to the female screw portion 26 so that the retaining portion 23 is moved away from the stopper portion of the holding portion 21, the biasing member 27 is stretched, and the elastic force (biasing force) becomes small. The biasing force adjustment portion 24 is not limited to these embodiments and may be configured in an appropriate manner depending on the configuration of the biasing member 27. Furthermore, the biasing member 27 is not limited to a compression coil spring, but may be other spring members such as a tension coil spring or a torsion spring, or it may be an elastic member such as rubber, and the holding portion 21 and the guide portion 22 may be deformed appropriately according to such a biasing member 27.

[0028] In the gas introduction device 10 configured as described above, the valve body 18 is displaced as follows, and the depressurization chamber 2 is opened to the atmosphere. When the atmospheric release valve 6 is in the closed state, that is, when the cylindrical body 11 and the depressurization chamber 2 are not in communication, the valve body 18 is set to the fully open position by the biasing member 27, as shown in Figure 2(a). When the atmospheric release valve 6 is opened, that is, when the cylindrical body 11 and the decompression chamber 2 are in communication, the valve body 18 is drawn in by the negative pressure in the decompression chamber 2 and moves to the closed position against the biasing force of the biasing member 27, as shown in Figure 2(b). The gap between the valve body 18 and the periphery of the opening 13 and the biasing member 27 should be configured such that when the atmospheric release valve 6 is opened, the valve body 18 moves to the closed position due to the pressure difference between the pressure inside the decompression chamber 2 and atmospheric pressure.

[0029] When the atmospheric release valve 6 is opened and the valve body 18 is in the closed position, a small amount of gas is introduced into the decompression chamber 2 via the small amount gas introduction section 14. As shown in Figure 3, the flow velocity of the gas introduced into the decompression chamber 2 gradually decreases as the gas is introduced through the small amount gas introduction section 14, because the pressure difference between the inside of the decompression chamber 2 and the atmosphere decreases. The graphs in Figures 3, 6, and 8 schematically show the change in the flow velocity of the gas passing downstream of the downstream opening 16 of the small amount gas introduction section 14 in the cylindrical body 11 (towards the cylindrical part of the atmospheric release valve 6). Furthermore, as the pressure difference between the decompression chamber 2 and the atmosphere decreases further, the valve body 18 is pushed to the fully open position by the biasing member 27, as shown in Figure 2(c). In other words, if the biasing force of the biasing member 27 becomes greater than the suction force due to the pressure difference between the decompression chamber 2 and the atmosphere, the valve body 18 is displaced to the fully open position. Figure 2(c) shows the valve body 18 in the process of opening, but it reaches the fully open position relatively instantaneously.

[0030] As described above, when the valve body 18 is in the fully open position, as shown in Figure 3, a larger amount of gas than described above is introduced towards the depressurization chamber 2 through the opening 13 and the small gas introduction section 14 of the gas introduction device 10, and the flow velocity increases relatively rapidly. At this time, since gas has already been introduced through the small gas introduction section 14, the pressure difference between the inside of the depressurization chamber 2 and the atmosphere is small, so there is no rapid pressure increase that would adversely affect the object being processed, and the flow velocity is approximately the same as the gas flow velocity at the initial stage of opening the atmospheric release valve 6. Then, similar to the above, as gas is introduced, the pressure difference between the decompression chamber 2 and the atmosphere decreases, causing the flow velocity to gradually decrease to zero, that is, the decompression chamber 2 to reach atmospheric pressure. With this configuration, it is possible to reduce the time required for the decompression chamber 2 to reach atmospheric pressure while mitigating the rapid pressure increase in the decompression chamber 2. In other words, if only a small gas introduction section 14 is provided, as shown by the dashed line in Figure 3, the flow velocity decreases as the pressure difference between the decompression chamber 2 and the atmosphere decreases, and the time required for the decompression chamber 2 to reach atmospheric pressure tends to increase.

[0031] Next, a modified example of the gas introduction device will be explained with reference to Figures 4 to 8. In each of the following modifications, the differences from the previously described example will be explained primarily, and similar configurations will be omitted or briefly described. In addition, in each of the following modifications, the effects and benefits that are achieved in the same way as in the previously described example will also be omitted or briefly described. Furthermore, the gas introduction device in each modification may be provided in the vacuum treatment device 1, as in the example described above.

[0032] Figures 4 to 6 schematically show an example of a gas introduction device 10A according to the first modified example and an example of the change in flow velocity when using it. In this modified example, at least one of the valve body 18A and the peripheral edge of the opening 13 opened and closed by the valve body 18A is provided with an opening area variable portion 19A that makes the opening area of ​​the valve body 18A smaller than that of the fully open position during the opening process. With this configuration, since the opening area of ​​the valve body 18A during the opening process is smaller than that of the fully open position, it is possible to more effectively prevent adverse effects from a rapid pressure increase on the object being processed in the decompression chamber 2. In this modified example, the valve body 18A is provided with an opening area variable portion 19A.

[0033] The valve body 18A is positioned in a closed position, with its outer peripheral end contacting the end face of the cylindrical body 11 on the opening 13 side, similar to the example described above. The variable opening area portion 19A is provided so as to be connected to the cylindrical body 11 side of the valve body 18A, and is columnar in shape so that it is inserted into the cylindrical body 11 when the valve body 18A is in the closed position. In other words, the valve body 18A is configured such that the variable opening area portion 19A, which is smaller in diameter than the large-diameter portion, is provided on the cylindrical body 11 side of the large-diameter portion including the outer peripheral end that abuts against the end face of the cylindrical body 11 on the opening 13 side. This variable opening area portion 19A is cylindrical in shape and is arranged coaxially in the cylindrical hollow portion of the cylindrical body 11. The outer diameter of this variable opening area portion 19A is smaller than the inner diameter of the cylindrical body 11 so that a gap is formed between its outer peripheral surface and the inner peripheral surface of the cylindrical body 11 that allows gas to pass through.

[0034] In other words, as shown in Figures 5(a) and (b), when the valve body 18A is in the process of opening, with the variable opening area 19A displaced to the open side inside the cylindrical body 11, gas is introduced through the gap between the outer surface of the variable opening area 19A and the inner surface of the cylindrical body 11. The opening area of ​​the valve body 18A in the process of opening may be understood as the value obtained by subtracting the cross-sectional area of ​​the variable opening area 19A from the hollow cross-sectional area of ​​the cylindrical body 11, or it may be the effective cross-sectional area. The opening area (effective cross-sectional area) of the valve body 18A in the process of opening only needs to be smaller than the opening area (effective cross-sectional area) of the valve body 18A in the fully open position, for example, it may be about 1 / 20 to 9 / 10 of the opening area (effective cross-sectional area) of the valve body 18A in the fully open position. The axial dimensions of the variable opening area section 19A may be set to an appropriate size so that the partially open state continues for a predetermined time (for example, about 0.5 to 5 seconds).

[0035] In the gas introduction device 10A configured as described above, the valve body 18A is displaced as follows, and the depressurization chamber 2 is opened to the atmosphere. Similar to the example described above, when the atmospheric release valve 6 is closed, the valve body 18A is set to the fully open position by the biasing member 27. When the atmospheric release valve 6 is opened, the valve body 18A is drawn in by the negative pressure in the decompression chamber 2 and moves to the closed position against the biasing force of the biasing member 27 (see Figures 4(a) and (b)). In this state, similar to the example described above, a small amount of gas is introduced into the decompression chamber 2 via the small amount of gas introduction section 14. As shown in Figure 6, the flow velocity of the gas introduced into the decompression chamber 2 gradually decreases as the gas is introduced via the small amount of gas introduction section 14, because the differential pressure between the inside of the decompression chamber 2 and the atmosphere decreases. As the pressure difference between the decompression chamber 2 and the atmosphere decreases further, the valve body 18A is displaced to the open side by the biasing force of the biasing member 27, as shown in Figures 5(a) and (b), and gas is introduced through the gap between the variable opening area section 19A and the cylindrical body 11. At this time, as the valve body 18A is displaced to the open side, the resistance (pipe resistance) when passing through the gap between the variable opening area section 19A and the cylindrical body 11 decreases (the passage path becomes shorter), so in the intermediate opening state, as shown in Figure 6, the gas flow velocity decreases relatively slowly.

[0036] Then, when the valve body 18A is in the fully open position, as gas is introduced, the pressure difference between the decompression chamber 2 and the atmosphere decreases, causing the flow velocity to gradually decrease to zero, that is, the decompression chamber 2 to reach atmospheric pressure. Figure 6 shows an example in which the gas flow velocity decreases slowly up to the fully open position, including the final stage of the valve body 18A's opening process. However, depending on the pressure difference between the decompression chamber 2 and the atmosphere, the flow velocity may temporarily increase after the variable opening area part 19A is displaced outside the cylindrical body 11 (final stage of the opening process). In this modified example, the variable opening area portion 19A is shown as a cylindrical shape with a uniform outer diameter throughout the axial direction. However, instead of this configuration, the guide portion 22 may be made into a multi-stage cylindrical or frustoconical shape, where the outer diameter decreases gradually or continuously as it approaches the retaining portion 23. With such a configuration, the opening area increases as the valve body 18A is displaced towards the open side during the opening process, similar to the second modified example described later.

[0037] Figures 7 and 8 schematically show an example of a gas introduction device 10B according to the second modified example and an example of the change in flow velocity when using it. In this modified example, the valve body 18B is provided with an opening area variable portion 19B, which is at least one of the valve body 18B and the peripheral edge of the opening 13 that is opened and closed by the valve body 18B. In this modified example, the valve body 18B has an outer diameter smaller than the inner diameter of the cylindrical body 11 throughout its entire axial direction. In other words, the valve body 18B does not have an outer peripheral end that abuts against the end face of the cylindrical body 11 on the opening 13 side. As shown in Figure 7(b), in the closed position, the valve body 18B is entirely housed within the cylindrical body 11, and the outer peripheral surface of its outer end (the end on the stopper side of the holding part 21) is close to the inner peripheral surface of the cylindrical body 11. Alternatively, the valve body 18B may be configured to have an outer peripheral end that abuts against the end face of the cylindrical body 11 on the opening 13 side.

[0038] The variable opening area portion 19B opens on the outer circumferential surface of the valve body 18B and is groove-shaped, extending in the axial direction. This variable opening area portion 19B also opens on the end face of the valve body 18B on the retaining portion 23 side. This variable opening area portion 19B may also open on the end face on the outer end side of the valve body 18B. This variable opening area portion 19B is formed such that the opening area gradually increases steplessly as the valve body 18B is displaced from the closed position to the fully open position. In other words, the groove cross-sectional area perpendicular to the longitudinal direction of the groove of the variable opening area portion 19B is formed to gradually increase steplessly from the outer end (the end on the stopper side of the holding portion 21) towards the retaining portion 23 side. This groove cross-sectional area perpendicular to the longitudinal direction of the groove of the variable opening area portion 19B may be considered as the opening area. Unlike the examples described above, the valve body 18B is configured such that even in the fully open position, a portion of it (the end on the retaining portion 23 side) is located inside the cylindrical body 11, as shown in Figure 7(a). With this configuration, the outer surface of the valve body 18B is brought close to the inner surface of the cylindrical body 11, while preventing snagging and allowing for smooth opening and closing.

[0039] In the gas introduction device 10B configured as described above, the valve body 18B is displaced as follows, and the depressurization chamber 2 is opened to the atmosphere. Similar to the examples described above, when the atmospheric release valve 6 is closed, the valve body 18B is held in the fully open position by the biasing member 27. When the atmospheric release valve 6 is opened, the valve body 18A is drawn in by the negative pressure of the decompression chamber 2 and moves against the biasing force of the biasing member 27 to the closed position (see Figures 7(a) and (b)). As a result, similar to the examples described above, a small amount of gas is introduced into the decompression chamber 2 via the small amount of gas introduction section 14. As shown in Figure 7(c), as the differential pressure between the inside of the decompression chamber 2 and the atmosphere decreases, the biasing force of the biasing member 27 displaces the valve body 18B to the open side, and gas is introduced through the variable opening area section 19B. The example in Figure 8 shows an example where the gas flow velocity is approximately constant when the valve body 18B is displaced from the closed position to the fully open position. In other words, the variable opening area section 19B described above may be formed such that the gas flow velocity is approximately constant when the valve body 18B is displaced from the closed position to the fully open position. Alternatively, the gas flow velocity may decrease or increase as the valve body 18B is displaced from the closed position to the fully open position. When the valve body 18B is in the fully open position, as gas is introduced, the pressure difference between the decompression chamber 2 and the atmosphere decreases, causing the flow velocity to decrease to zero, that is, the decompression chamber 2 becomes atmospheric pressure.

[0040] In this modified example, a single groove-shaped opening area variable portion 19B is shown on the valve body 18B. However, instead of this configuration, multiple opening area variable portions 19B may be provided at intervals (preferably equal intervals) in the circumferential direction of the valve body 18B, or the entire valve body 18B may be shaped like a frustocone. Furthermore, instead of providing an opening area variable portion 19B that continuously changes the opening area, a configuration may be provided that changes the opening area in steps. Furthermore, while the first and second modified examples show examples in which variable opening area sections 19A and 19B are provided on the valve bodies 18A and 18B, alternatively to or in addition to such configurations, the variable opening area section may be provided on the peripheral edge of the opening 13 opened and closed by the valve bodies 18A and 18B (e.g., the inner surface of the outer end of the cylindrical body 11). In this case, for example, the inner surface of the outer end of the cylindrical body 11 may be provided with grooves, steps, tapers, etc., that increase in opening area as they move outward.

[0041] In the examples described above, the biasing mechanism 20 is shown to be equipped with a biasing force adjustment unit 24 that adjusts the biasing force of the biasing member 27 that biases the valve bodies 18, 18A, and 18B toward the fully open position. However, a configuration without such a biasing force adjustment unit 24 is also possible. In the examples described above, a flow rate adjustment unit 17 is provided in the small gas introduction section 14, which allows for increasing or decreasing the opening area. However, a configuration without such a flow rate adjustment unit 17 is also possible. In this case, the cylindrical body 11 or valve bodies 18, 18A, 18B may be provided with small holes or the like that constitute the small gas introduction section 14. The specific configurations of each part of the gas introduction devices 10, 10A, and 10B according to this embodiment, and the operation of opening the depressurized chamber 2 to the atmosphere using the gas introduction devices 10, 10A, and 10B, are not limited to the above configuration, and various other modifications are possible. [Explanation of Symbols]

[0042] 10, 10A, 10B Gas introduction device 11. Cylindrical body 12 Mounting part 13 Aperture 14. Small gas introduction section 17 Flow rate adjustment section 18, 18A, 18B valve body 19A, 19B Variable opening area section 20 Biasing mechanism 24 Force adjustment section 27. Biasing member 2. Decompression chamber 6. Atmospheric release valve 7 aperture 8 Mounting part

Claims

1. A gas introduction device attached to the atmospheric intake side of an atmospheric release valve that opens a depressurization chamber, which is reduced to a pressure lower than atmospheric pressure, to the atmosphere, A gas introduction device comprising: a valve body for opening and closing the atmospheric intake side of the atmospheric release valve; a small gas introduction section having an opening area smaller than the opening area of ​​the valve body in the fully open position, thereby enabling gas introduction regardless of the position of the valve body; and a biasing mechanism that biases the valve body, which is in the closed position due to the negative pressure of the decompression chamber when the atmospheric release valve is opened, toward the fully open position.

2. In claim 1, A gas introduction device characterized by having a cylindrical body having a mounting portion at one end that is attached to the mounting portion on the atmospheric intake side of the atmospheric release valve so as to communicate with the atmospheric intake side opening of the atmospheric release valve, and an opening at the other end that is opened and closed on the valve body.

3. In claim 2, The gas introduction device is characterized in that the small amount of gas introduction section is provided in the cylindrical body.

4. In any one of claims 1 to 3, The gas introduction device is characterized in that the small-volume gas introduction section is provided with a flow rate adjustment section that allows the opening area to be increased or decreased.

5. In any one of claims 1 to 3, The gas introduction device is characterized in that the biasing mechanism is provided with a biasing force adjustment unit for adjusting the biasing force of a biasing member that biases the valve body toward the fully open position.

6. In any one of claims 1 to 3, A gas introduction device characterized in that at least one of the valve body and the peripheral edge of the opening opened and closed by the valve body is provided with an opening area variable portion that makes the opening area of ​​the valve body smaller than that of the fully open position during the opening process.

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