TW201511125A - Vacuum device and valve control method - Google Patents

Abstract

The invention provides a vacuum device which allows the treatment using large-flow treatment gas and a valve control method. In a plasma processing device, APC valves in four first exhaust pipes in exhaust pipes connected with a processing container are set to be with the opening degree of 300 (30%) and APC valves in the remaining four second exhaust pipes are set to be with the opening degree of 1000 (100%). Thus, as shown by the curve (C), the pressure control in the processing container and the flow control of the treatment gas can be performed between the curve (A) obtained when the opening degree of the APC valves is set to be 300 and the curve (B) obtained when the opening degree of the APC valves is set to be 1000. Compared with the curve (A), the curve (C) allows discharge of larger flow of treatment gas (Q1 < Q2) under the same pressure (P1). Besides, compared with the curve (A), the curve (C) allows the treatment of lower pressure (P1 < P2) on the condition of the same flow (such as Q1).

Description

Vacuum device and valve control method

The present invention relates to a vacuum apparatus and a valve control method for performing plasma treatment or the like on a target object.

In the manufacturing process of an FPD (flat panel display), various plasma treatments such as plasma etching, plasma ashing, and plasma film formation are performed on the FPD substrate. As a device for performing plasma treatment as described above, for example, a parallel plate type plasma processing device or an inductively coupled plasma (ICP) processing device is known. These plasma processing apparatuses are configured as a vacuum apparatus that performs a process of reducing the pressure inside the processing container to a vacuum state.

In recent years, in order to process a large-sized FPD substrate, the processing container has also become large. Therefore, a plurality of vacuum pumps for decompressing and decompressing the inside of the processing container are generally provided. In the upstream side of the exhaust direction of the vacuum pumps, an automatic pressure control valve (hereinafter referred to as "APC valve") is provided, and the inside of the processing container is adjusted by automatically adjusting the conduction of the exhaust path. pressure. For example, in a plasma etching apparatus, a process is performed by a mass flow controller when performing a process. A method of controlling the desired process pressure by supplying a fixed flow of process gas to the vessel while simultaneously regulating the conduction of the exhaust path by an APC valve.

As a conventional technique for pressure control of a vacuum apparatus, Patent Document 1 proposes a vacuum apparatus including: a vacuum exhausting means connected to a plurality of exhaust paths; and a gate valve provided in a plurality of exhaust paths A part of the exhaust path; and the APC valve are provided corresponding to an exhaust path other than the exhaust path in which the gate valve is provided.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2009-16382 (Fig. 2, etc.)

Conventionally, when the APC valve is separately provided in the exhaust paths of a plurality of systems, one of them is configured as a main valve, and the other is configured as a slave valve. Each of the slave valves operates in conjunction with the main valve. That is, all of the APC valves are configured to perform switching operations in synchronization with each other.

However, as a characteristic of the APC valve, when the opening degree of the valve exceeds a certain level, the amount of change in conduction per 1% of the opening degree becomes large, and the controllability of the pressure is lowered. Therefore, the upper limit of the opening degree of the APC valve is usually set to about 30%. As a result, the effective exhaust velocity of the vacuum pump is limited by the opening degree of the APC valve, and even It is also impossible to fully utilize its performance by using a vacuum pump with a large exhaust capacity. Therefore, in order to obtain the required exhaust speed, it is necessary to further use a vacuum pump having a large exhausting capacity, which is one of the causes of an increase in the cost of the apparatus. For example, in order to increase the etching rate, a plasma etching process requiring a large flow rate of etching gas is known. In such a plasma etching process, the exhaust of a plurality of systems caused by the conventional APC valve and the vacuum pump is combined, and the APC valve is set to be synchronized and the same degree of opening and closing. Due to the limitation of the opening degree, it is impossible to Fully improve the conduction of the exhaust system. Therefore, it is difficult to carry out the treatment using the processing gas at a large flow rate and a large exhaust gas amount under high vacuum conditions, or it is necessary to further replace the specification of the vacuum pump with a high exhaust gas capacity.

Accordingly, it is an object of the present invention to provide a vacuum apparatus which can correspond to a process for using a process gas at a large flow rate.

A vacuum apparatus according to the present invention includes: a processing container that can accommodate a target object and maintains a vacuum inside; a gas supply source that supplies a processing gas to the processing chamber via a gas supply path; and a flow rate adjusting device that is provided in the gas supply a path for adjusting a supply flow rate of the processing gas; and a pressure detecting means for detecting a pressure in the processing container. Further, the vacuum apparatus according to the present invention includes: a plurality of first exhaust passages connected to the processing container and provided with a first valve; and a plurality of second exhaust passages connected to the processing container, and a second valve; an exhaust device connected to the first exhaust path or the second exhaust path; and The system controls the first valve and the second valve based on the detected pressure value and the set pressure value detected by the pressure detecting device so that the pressure in the processing container is set to a predetermined value. Further, in the vacuum apparatus of the present invention, the first valve is capable of variably adjusting a valve for conducting the first exhaust path, and the second valve is for switching a switch of the second exhaust path. valve. Further, in the vacuum apparatus of the present invention, the control unit includes: an opening degree adjustment unit that collectively adjusts an opening degree of the first valve provided in each of the plurality of first exhaust paths; and a switch switching unit The switching of the switches of the second valves provided in the plurality of second exhaust paths is collectively performed.

In the vacuum apparatus of the present invention, one of the first exhaust passage and the second exhaust passage may be connected to the exhaust device.

In the vacuum apparatus of the present invention, the control unit is configured to set, in the first exhaust passage, the exhaust gas flow rate when the conduction is adjusted by the first valve to V11, and the first exhaust path. When the exhaust gas flow rate when the opening degree of the first valve is fully opened is V12, and the exhaust gas flow rate of the second exhaust path is set to V2, the intermediate portion satisfies the relationship of the following formula (1). In the method, the opening degree of the first valve and the switch of the second valve are adjusted. n × V11 ≦ m × V2 ≦ n × V12 (1) (here, n indicates the number of the first exhaust paths, and m indicates the number of the second exhaust paths).

The vacuum device of the present invention can also be used to variably adjust The valve that conducts the second exhaust path described above, and only the switch actuator is used as the second valve.

The vacuum apparatus of the present invention may be an etching apparatus that etches a target object.

In the vacuum apparatus of the present invention, the object to be processed may be a substrate for FPD.

The control method of the valve of the present invention is a control method of a valve in a vacuum apparatus. The valve control method according to the present invention includes: a processing container that can accommodate the object to be processed and maintains a vacuum inside; a gas supply source supplies a processing gas to the processing chamber via a gas supply path; and a flow rate adjusting device is provided in the a gas supply path for adjusting a supply flow rate of the processing gas; and a pressure detecting means for detecting a pressure in the processing chamber. Further, in the valve control method of the present invention, the vacuum device includes a plurality of first exhaust passages connected to the processing container, and is provided with a first valve and a plurality of second exhaust paths. The second valve is connected to the processing container, and the exhaust device is connected to the first exhaust path or the second exhaust path. Further, in the valve control method of the present invention, the vacuum device includes a control unit that detects the pressure in the processing container so as to be determined by the pressure detecting device. The detected pressure value and the set pressure value respectively control the first valve and the second valve. Further, in the valve control method of the present invention, the first valve is capable of variably adjusting a valve for conducting the first exhaust path, and the second valve is for performing switching of the second exhaust path. The valve to be switched, the control unit includes: an opening degree adjustment unit, which concentrates Adjusting a degree of opening of the first valve provided in each of the plurality of first exhaust paths; and switching the switching unit to collectively switch between switches of the second valves provided in the plurality of second exhaust paths . Further, the valve control method according to the present invention includes: a step of synchronizing and opening all of the second valves simultaneously; and a detection pressure value and a set pressure value detected by the pressure detecting device; All of the aforementioned first valves are synchronized and adjusted.

In the control method of the valve according to the present invention, in the first exhaust passage, the exhaust gas flow rate at the time of conduction adjustment is set to V11 by the first valve, and the first exhaust passage is made to be in the first exhaust passage. When the exhaust gas flow rate at the time when the opening degree of the first valve is fully opened is V12, and the exhaust gas flow rate of the second exhaust path is set to V2, the relationship is adjusted so as to satisfy the relationship of the following formula (1). The opening degree of the first valve and the switch of the second valve. n × V11 ≦ m × V2 ≦ n × V12 (1) (here, n indicates the number of the first exhaust paths, and m indicates the number of the second exhaust paths).

According to the present invention, it is possible to suppress the cost of the apparatus in a large-sized vacuum apparatus and simultaneously perform a process of using a large-flow process gas.

1‧‧‧Processing container

1a‧‧‧ bottom wall

1b‧‧‧ side wall

1c‧‧‧ cover

11‧‧‧Base

12‧‧‧Substrate

13,14‧‧‧ Sealing members

15‧‧‧Insulating components

31‧‧‧ sprinkler

33‧‧‧ gas diffusion space

35‧‧‧ gas discharge hole

37‧‧‧ gas inlet

39‧‧‧Processing gas supply pipe

41‧‧‧ valve

43‧‧‧The mass flow controller

45‧‧‧ gas supply source

51‧‧‧Exhaust opening

53‧‧‧Exhaust pipe

53a‧‧‧Flange

53A‧‧‧1st exhaust pipe

53B‧‧‧2nd exhaust pipe

55, 55A, 55B‧‧‧APC valve

57‧‧‧Exhaust device

61‧‧‧ pressure gauge

71‧‧‧Power supply line

73‧‧‧matching box (M.B.)

75‧‧‧High frequency power supply

100,100A‧‧‧ plasma etching device

Fig. 1 is a cross-sectional view schematically showing the configuration of a plasma etching apparatus according to a first embodiment of the present invention.

Fig. 2 is a plan view showing a bottom wall of the plasma etching apparatus of Fig. 1.

Fig. 3 is a block diagram showing a hardware configuration of a control unit of the plasma etching apparatus of Fig. 1.

FIG. 4 is a block diagram showing the hardware configuration of the module controller of FIG. 3. FIG.

FIG. 5 is a functional block diagram showing the function of the module controller of FIG. 3. FIG.

Fig. 6 is a characteristic diagram showing the relationship between the flow rate of the process gas and the pressure for explaining the action of the present invention.

Fig. 7 is a schematic view showing the configuration of a plasma etching apparatus according to a second embodiment of the present invention.

Fig. 8 is a plan view showing the bottom wall of the plasma etching apparatus of Fig. 7.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]

Fig. 1 is a cross-sectional view showing a schematic configuration of a plasma etching apparatus according to a first embodiment of the processing apparatus of the present invention. As shown in FIG. 1 , the plasma etching apparatus 100 is a capacitive coupling type parallel plate type plasma etching apparatus which etches a to-be-processed object, such as the FPD glass substrate (Hereafter, it is only described as "substrate") S. In addition, FPD is exemplified by a liquid crystal display. (LCD), electroluminescence (EL) display, plasma display panel (PDP), and the like.

The plasma etching apparatus 100 is a processing container 1 which is formed of aluminum which is anodized (aluminum-treated) inside and formed into a rectangular tube shape. The main body (container body) of the processing container 1 is configured by a bottom wall 1a and four side walls 1b (only two are shown). Further, the upper portion of the main body of the processing container 1 is joined to the lid body 1c. Although not shown in the drawings, the side wall 1b is provided with a gate valve opening and a gate valve for sealing the substrate transfer opening.

The lid body 1c is configured to be switchable with respect to the side wall 1b by a switch mechanism (not shown). In a state where the lid body 1c is closed, the joint portion between the lid body 1c and each side wall 1b is sealed by the O-ring 3, thereby maintaining the airtightness in the processing container 1.

A frame-shaped insulating member 10 is disposed at the bottom of the processing container 1. The insulating member 10 is provided with a susceptor 11 on which a mounting table of the substrate S can be placed. The base 11 of the lower electrode is also provided with a substrate 12. The base material 12 is formed of a conductive material such as aluminum or stainless steel (SUS). The base material 12 is disposed on the insulating member 10, and a sealing member 13 such as an O-ring is provided at a joint portion of the two members to maintain airtightness. The insulating member 10 and the bottom wall 1a of the processing container 1 are also kept airtight by a sealing member 14 such as an O-ring. The outer periphery of the side portion of the substrate 12 is surrounded by the insulating member 15. Thereby, the insulation of the side surface of the susceptor 11 can be ensured, and abnormal discharge at the time of plasma processing can be prevented.

Above the susceptor 11, there is a parallel with the pedestal 11 And the nozzle 31 having the upper electrode function in the opposite direction. The head 31 is supported by a lid 1c of the upper portion of the processing container 1. The head 31 is formed in a hollow shape, and a gas diffusion space 33 is provided inside. Further, a plurality of gas discharge holes 35 for discharging the processing gas are formed on the lower surface of the head 31 (opposite to the susceptor 11). The head 31 is in a grounded state and together with the susceptor 11 constitutes a pair of parallel plate electrodes.

A gas introduction port 37 is provided in the vicinity of the center of the upper portion of the head 31. A process gas supply pipe 39 is connected to the gas introduction port 37. In the processing gas supply pipe 39, a gas supply source 45 for supplying a processing gas for etching is connected via two valves 41, 41 and a mass flow controller (MFC) 43. The processing gas may be, for example, a halogen gas or an O ₂ gas, or a rare gas such as an Ar gas.

The bottom wall 1a in the processing container 1 is formed with an exhaust opening 51 penetrating through a plurality of portions (for example, eight places). An exhaust pipe 53 is connected to each of the exhaust openings 51. Each of the exhaust pipes 53 has a flange portion 53a at its end, and is fixed in a state in which an O-ring (not shown) is interposed between the flange portion 53a and the bottom wall 1a. An APC valve 55 and an exhaust device 57 are connected to each of the exhaust pipes 53.

Here, an example of arrangement of the exhaust path of the plasma etching apparatus 100 and the APC valves 55A and 55B will be described with reference to FIG. 2 . Figure 2 is a plan view of the bottom wall 1a of the plasma etching apparatus 100 of Figure 1. For convenience of explanation, in FIG. 2, the arrangement of the four first exhaust pipes 53A and the four second exhaust pipes 53B is shown in the eight exhaust openings 51. The exhaust pipe 53 includes a plurality (for example, four) of the first row as the first exhaust path. The air pipe 53A and a plurality of (for example, four) second exhaust pipes 53B as the second exhaust path. An APC valve 55A as a first valve is provided in the first exhaust pipe 53A. An APC valve 55B as a second valve is provided in the second exhaust pipe 53B. The APC valve 55A changes the degree of opening and closing according to a control signal from the control unit 80, and automatically adjusts the conduction of the first exhaust pipe 53A. The APC valve 55B is set to perform switching operations of only two states of full open or fully closed, and the second exhaust pipe 53B is opened or closed based on a control signal from the control unit 80.

As shown in Fig. 2, two first exhaust pipes 53A and 53A are arranged adjacent to each other, and two of them are arranged symmetrically in the vicinity of the two short sides of the opposite side with respect to the center of the bottom wall 1a. Therefore, the APC valve 55A is also configured in the same manner. Further, two second exhaust pipes 53B and 53B are arranged adjacent to each other, and two of them are arranged symmetrically in the vicinity of the two long sides of the opposite side with respect to the center of the bottom wall 1a. Therefore, the APC valve 55B is also configured in the same manner. The first exhaust pipe 53A and the second exhaust pipe 53B are connected to the exhaust device 57, respectively. The exhaust device 57 is provided with a vacuum pump such as a turbo molecular pump, and is configured to evacuate the inside of the processing container 1 to a predetermined reduced pressure environment.

In the plasma etching apparatus 100, a pressure gauge 61 that measures the pressure in the processing container 1 is provided. The pressure gauge 61 is connected to the control unit 80, and supplies the measurement result of the pressure in the processing container 1 to the control unit 80 in an instant manner.

A power supply line 71 is connected to the substrate 12 of the susceptor 11. In the power supply line 71, a high frequency power supply 75 is connected via a matching box (M.B.) 73. Thereby, it is possible to high from the high frequency power source 75, for example, 13.56 MHz. The frequency power is supplied to the susceptor 11 as a lower electrode. Further, the power supply line 71 is introduced into the processing container 1 through the power supply opening 77 formed through the bottom wall 1a as a through opening.

Each component of the plasma etching apparatus 100 is configured to be connected to the control unit 80 and controlled. Referring to Fig. 3, a control unit 80 of a substrate processing system included in a part of the plasma etching apparatus 100 of the present embodiment will be described. FIG. 3 is a block diagram showing the hardware configuration of the control unit 80. As shown in FIG. 3, the control unit 80 includes: a device controller (hereinafter referred to as "EC") 81; a plurality of (only two are shown in FIG. 2, but they are not The present invention is limited to a module controller (hereinafter referred to as "MC") 83; and a switching hub (HUB) 85 to which EC81 and MC83 are connected.

The EC 81 is a main control unit (main control unit) that controls a plurality of MCs 83 and controls the overall operation of the substrate processing system. A plurality of MC83 systems are used to control the sub-control unit (slave controller) of the operation of each module including the plasma etching apparatus 100 under the control of the EC81. The switching hub 85 switches the MC83 connected to the EC81 in response to a control signal from the EC81.

EC81 is based on a control program for realizing various processes of the substrate S executed by the substrate processing system, and a processing program for recording processing condition data and the like, and transmits a control signal to each MC 83, thereby controlling the entire substrate disposal system. Actions.

The control unit 80 is further provided with: a subnet 87; DIST (Distribution) board 88; and input/output (hereinafter referred to as I/O) module 89. Each MC 83 is connected to the I/O module 89 via a subnet 87 and a DIST board 88.

The I/O module 89 has a plurality of I/O sections 90. The I/O unit 90 is connected to each terminal device of each module including the plasma etching apparatus 100. Although not shown, the I/O unit 90 is provided with an I/O board for controlling the input and output of the digital signal, the analog signal, and the serial signal. The control signals for the respective terminal devices are output from the I/O unit 90, respectively. Further, the output signals from the respective terminal devices are output to the I/O unit 90, respectively. In the plasma etching apparatus 100, as the terminal device connected to the I/O unit 90, for example, a mass flow controller (MFC) 43, an APC valve 55A, 55B, a pressure gauge 61, an exhaust device 57, and the like are exemplified.

The EC 81 is connected to a computer 93 as an MES (Manufacturing Execution System) that manages a manufacturing process in which the entire substrate processing system 100 is installed via a LAN (Local Area Network) 91. The computer 93 cooperates with the control unit 80 of the substrate processing system 100 to feed back the real-time information about the factory process to the core business system, and to perform the judgment on the process in consideration of the load of the entire plant. The computer 93 can also be connected to an information processing device such as another computer 95.

Next, an example of the hardware configuration of the MC 83 will be described with reference to FIG. The MC 83 is provided with a main control unit 101, an input device 102 such as a keyboard or a mouse, an output device 103 such as a printer, a display device 104, a memory device 105, an external interface 106, and a confluence connecting the devices to each other. Row 107. The main control unit 101 has a CPU (Central Processing Unit) 111), RAM (random access memory) 112, and ROM (read only memory) 113. As long as the memory device 105 is a memorable information device, it is not limited to any form, and may be, for example, a hard disk device or a compact disk device. Further, the memory device 105 records information on the computer-readable recording medium 115, and can read information from the recording medium 115. As long as the recording medium 115 is a memorable information, it is not limited to any form, and may be, for example, a hard disk, a compact disc, a flash memory, or the like. The recording medium 115 may be a recording medium on which the processing program of the plasma etching method of the present embodiment is recorded.

In the MC 83, the CPU 111 uses the RAM 112 as a work area and executes a program stored in the ROM 113 or the memory device 105, whereby the plasma etching process can be performed on the substrate S in the plasma etching apparatus 100 of the present embodiment. Further, the hardware configuration of the EC 81 and the computers 93 and 95 of FIG. 3 is also formed, for example, as shown in FIG.

Next, the functional configuration of the MC 83 will be described with reference to Fig. 5 . Figure 5 is a functional block diagram showing the function of the MC83. Further, in the following description, the hardware configuration of the MC 83 is formed as shown in FIG. 4, and reference may be made to the symbols in FIG. As shown in FIG. 5, the MC83 includes an opening degree adjustment unit 121 and a switch switching unit 123. These are implemented by the CPU 111 using the RAM 112 as a work area and executing a program stored in the ROM 113 or the memory device 105.

The opening degree adjustment unit 121 transmits a control signal to each APC valve based on the detected pressure value detected by the pressure gauge 61 and the set pressure value specified by the processing program or parameter previously stored in the memory device 105. 55A, to adjust the opening and closing degree of each APC valve 55A in order to The desired pressure is formed in the processing vessel 1 of the plasma etching apparatus 100. The opening degree of the APC valve 55A is, for example, 1000 grades divided into 0 to 1000, and the predetermined degree of opening and closing is sent from the opening degree adjustment unit 121 of the MC 83 as digital output (DO) information to each APC valve 55A. .

The switch switching unit 123 transmits a control signal to each of the APC valves 55B based on a processing program or a parameter stored in advance in the memory device 105, thereby collectively switching the switches of the APC valves 55B at predetermined timings. The switching command of the switch of the APC valve 55B is sent from the switch switching unit 123 of the MC 83 to the APC valve 55B as digital output (DO) information.

Next, the processing operation of the plasma etching apparatus 100 configured as described above will be described. First, in a state in which the gate valve (not shown) is opened, the substrate S as the object to be processed is carried into the processing container 1 by the chuck of the transfer device (not shown) through the substrate transfer opening. Base 11. Then, the gate valve will be closed, and the inside of the processing container 1 is evacuated to a predetermined degree of vacuum by the exhaust device 57. In this case, first, the control signal is sent from the switch switching portion 123 of the MC 83 to each of the APC valves 55B, and all of the APC valves 55B are set to be fully open. Moreover, the opening degree adjustment unit 121 of the MC 83 is configured to monitor the detected pressure value of the pressure gauge 61 and send a control signal to each of the APC valves 55A, thereby collectively adjusting the opening degree of each APC valve 55A so that the processing container 1 is processed. The inside is formed to the desired pressure.

Next, the valve 41 is opened, passing through the gas supply source 45. The gas supply pipe 39 and the gas introduction port 37 introduce the process gas into the gas diffusion space 33 of the shower head 31. At this time, the flow rate control of the processing gas is performed by the mass flow controller 43. The processing gas introduced into the gas diffusion space 33 is further uniformly discharged to the substrate S placed on the susceptor 11 via the plurality of discharge holes 35, and the pressure in the processing container 1 is maintained at a predetermined value.

In this case, the high frequency power is applied from the high frequency power source 75 to the susceptor 11 via the matching box 73. Thereby, a high-frequency electric field is generated between the susceptor 11 as the lower electrode and the shower head 31 as the upper electrode, and the processing gas is dissociated and plasmatized. The substrate S is subjected to an etching treatment by the plasma.

In the plasma etching apparatus 100 of the present embodiment, the MC 83 monitors the detected pressure value of the pressure gauge 61 by the opening degree adjustment unit 121 of the MC 83 during the plasma etching process, and transmits the control signal to each APC. The valve 55A thereby centrally adjusts the opening degree of each APC valve 55A so that the inside of the processing container 1 is formed to a desired pressure.

Further, the switch switching unit 123 of the MC 83 holds all of the APC valves 55B fully open during the plasma etching process. By making a plurality of (for example, four) APC valves 55B fully open, the exhaust capability of the exhaust device 57 connected to the second exhaust pipe 53B can be maximized, and processing using a large flow rate can be realized. Gas etching process.

After the etching treatment is applied, the application of the high-frequency power from the high-frequency power source 75 is stopped, and after the gas introduction is stopped, the inside of the processing chamber 1 is depressurized to a predetermined pressure. Next, the gate valve is opened, and the substrate S is received from the susceptor 11. The chuck is transported to the substrate transfer opening of the processing container 1 from the chuck of the transfer device (not shown). By the above operation, the plasma etching treatment for one substrate S is completed.

<action>

Next, the action of the plasma processing apparatus 100 of the present embodiment will be described with reference to Fig. 6 . FIG. 6 shows a pressure change (vertical axis) when the inside of the processing container 1 of the plasma etching apparatus 100 is evacuated and the processing gas is introduced simultaneously using the exhaust device 57, based on actual experimental data. A characteristic diagram relating to the flow rate of the processing gas (horizontal axis). The curve A indicates a case where the opening degree of all the APC valves 55 connected to the plurality of (for example, eight) exhaust pipes 53 of the processing container 1 is set to 300 (30%). The curve B indicates a case where the degree of opening of all the APC valves 55 connected to the plurality of (for example, eight) exhaust pipes 53 of the processing container 1 is set to 1000 (100%). From the comparison of the curve A and the curve B, it can be understood that even at the same pressure P1, the curve B which makes the opening degree of the APC valve 55 fully open can be more large than the curve A which sets the opening degree to 300. The flow rate of the process gas is exhausted (Q1 < Q3). In other words, in the case of the curve B, the processing can be performed at a lower pressure than the curve A even at the same flow rate.

In the plasma processing apparatus 100 of the present embodiment, the APC valve 55A is set to have an opening degree of 300 (30%) among the four first exhaust pipes 53A connected to the eight exhaust pipes 53 of the processing container 1. In the remaining four second exhaust pipes 53B, the APC valve 55B is set to the opening degree. 1000 (100%). Thereby, the pressure in the processing container 1 can be adjusted by the APC valve 55A of the four first exhaust pipes 53A, and the conduction of the remaining four second exhaust pipes 53B can be maximized at the same time. Therefore, as shown by the curve C in FIG. 6, between the curve A when the opening degree of the APC valve is set to 300 and the curve B when the opening degree of the APC valve is set to 1000, it can be performed in the processing container 1. Pressure control and flow control of the process gas. That is, compared to the curve A, even at the same pressure P1, the curve C is capable of exhausting a larger flow rate of the process gas (Q1 < Q2). Further, in the case of the curve C, the processing can be performed at a lower pressure (P1 < P2) at the same flow rate (for example, Q1) than the curve A.

As described above, in the plasma processing apparatus 100 of the present embodiment, the pressure control in the processing container 1 can be performed by the APC valve 55A provided in the first exhaust pipe 53A, and at the same time, the second exhaust gas can be provided. The APC valve 55B in the fully open state of the tube 53B achieves a large flow rate corresponding to the processing gas. The APC valve 55A provided in the first exhaust pipe 53A can be used in a range of 30% of the degree of opening and closing with good controllability of conduction. On the other hand, in the second exhaust pipe 53B, since the conduction can be maximized by the APC valve 55B having a degree of opening and closing of 100%, it is possible to use the lower exhaust gas instead of the second exhaust gas. The downgrading of the turbo molecular pump or the like of the exhaust device 57 of the tube 53B can further reduce the device cost.

In addition, the ratio of the number of the APC valves 55A provided in the first exhaust pipe 53A and the APC valve 55B provided in the fully open state of the second exhaust pipe 53B is not limited to 1:1, and can be appropriately set. That is, the APC valve 55A can be set to the fully open state by changing the adjustment opening degree. The setting ratio of the APC valve 55B is controlled between the curve A and the curve B of FIG. 6, and the pressure control and the flow rate of the processing gas flow rate are accurately performed in the processing container 1.

Further, the opening degree adjustment unit 121 and the switch switching unit 123 of the MC 83 set the exhaust gas flow rate to be V11 when the conduction is adjusted to a predetermined value by the APC valve 55A in the first exhaust pipe 53A. In the exhaust pipe 53A, the exhaust gas flow rate when the opening degree of the APC valve 55A is fully opened is set to V12, and when the exhaust gas flow rate of the second exhaust pipe 53B is set to V2, the relationship of the formula (1) is satisfied. In a manner, it is preferable to adjust the opening degree of the APC valve 55A and the switch of the APC valve 55B. n × V11 ≦ m × V2 ≦ n × V12 (1) (here, n indicates the number of the first exhaust pipes 53A, and m indicates the number of the second exhaust pipes 53B.) Here, In the first exhaust pipe 53A, the degree of opening and closing when the conduction is adjusted to a predetermined value by the APC valve 55A can be, for example, 15% to 30% of the opening degree, and 15% to 25% of the opening degree. It is better in the range, and it is better to set the opening degree to 20%. When the relationship of the formula (1) is satisfied, the pressure in the processing container 1 is controlled with good control, and a large total amount of exhaust gas can be sufficiently obtained. When n × V11 > m × V2, the total exhaust gas flow rate in the m second exhaust pipes 53B is too small, and the amount of exhaust gas in the entire apparatus cannot be increased, so that it is difficult to cope with To the high flow process. On the other hand, in the case of m × V2 > n × V12, the total exhaust gas flow rate in the m second exhaust pipes 53B becomes excessive, which leads to the APC in the n first exhaust pipes 53A. The pressure controllability in the processing container 1 due to the valve 55A is lowered. Again, by full In the above formula (1), the setting ratio of the APC valve 55A and the APC valve 55B can also be optimally distributed.

Further, in the plasma etching apparatus 100 of the present embodiment, the second APC valve 55B is configured to be switched only by the switching degree of 0 or 1000. However, an on-off valve such as a gate valve may be used. Instead of part or all of the second APC valve 55B.

[Second Embodiment]

Next, a plasma etching apparatus according to a second embodiment of the present invention will be described with reference to Figs. 7 and 8 . In the following description, the differences from the first embodiment will be mainly described, and the same configurations as those of the first embodiment will not be repeated.

Fig. 7 is a schematic view showing the configuration of the plasma etching apparatus 100A of the present embodiment. Since the basic configuration of the plasma etching apparatus 100A is the same as that of the plasma etching apparatus 100 of the first embodiment, the detailed configuration will be omitted from illustration and description.

Fig. 8 is a plan view showing the bottom wall 1a of the plasma etching apparatus 100A. For convenience of explanation, in FIG. 8, the arrangement of the four first exhaust pipes 53A and the four second exhaust pipes 53B is shown in the eight exhaust openings 51. An APC valve 55A is provided in the first exhaust pipe 53A, and an APC valve 55B is provided in the second exhaust pipe 53B. In the present embodiment, as shown in FIG. 8, the first exhaust pipe 53A and the second exhaust pipe 53B are disposed adjacent to each other, and the two short sides of the opposite side are defined based on the center of the bottom wall 1a. Two long sides are symmetrically arranged. Therefore, APC valve 55A and APC valve 55B are also matched. Set.

The plasma etching apparatus 100A of the present embodiment has a configuration in which one exhaust unit 57 is connected to the downstream side in the exhaust direction of the two APC valves 55A and 55B. In the plasma etching apparatus 100A, the first exhaust pipe 53A and the second exhaust pipe 53B adjacent to the eight exhaust pipes 53 are merged to form a bus exhaust pipe 53AB, and one exhaust device is provided. 57 is connected to the manifold exhaust pipe 53AB. Even in such a configuration, the APC valve 55A provided in the first exhaust pipe 53A can be used in the range of 30% of the opening degree to the control of the conduction, and the pressure control in the processing container 1 can be simultaneously performed. On the other hand, in the second exhaust pipe 53B, since the conduction can be maximized by the APC valve 55B having a degree of opening and closing of 100%, it is possible to cope with the reduction of the exhaust capability of the entire plasma etching apparatus 100A. Large flow process. In the present embodiment, the first exhaust pipe 53A and the second exhaust pipe 53B are merged in the exhaust direction of the two APC valves 55A and 55B, and the first exhaust pipe 53A and the second exhaust pipe 53B are merged. An exhaust device 57 is connected to the manifold exhaust pipe 53AB. According to this configuration, even in the first embodiment, the number of the exhaust devices 57 having the expensive turbo molecular pump can be reduced by half, so that the device cost can be further reduced.

Other configurations and effects of the embodiment are the same as those of the first embodiment.

The embodiments of the present invention have been described in detail above with reference to the embodiments, but the present invention is not limited to the embodiments described above, and various modifications may be made. For example, the above embodiment is a parallel plate type plasma etching device. For example, the present invention can also be applied to plasma etching apparatuses such as an inductively coupled plasma device, a surface wave plasma device, an ECR (Electron Cyclotron Resonance) plasma device, a spiral wave plasma device, and the like. In addition, the vacuum apparatus which is necessary for the pressure adjustment in the chamber is not limited to the dry etching apparatus, and can be equally applied to, for example, a film forming apparatus or an ashing apparatus.

Further, the present invention is not limited to the case where the substrate for FPD is used as the object to be processed, and may be applied to, for example, a semiconductor wafer or a substrate for a solar cell as the object to be processed.

Claims (8)

A vacuum apparatus comprising: a processing container that can accommodate a target object and maintains a vacuum inside; a gas supply source supplies a processing gas to the processing chamber via a gas supply path; and a flow rate adjusting device is provided in the gas supply path, and Adjusting the supply flow rate of the processing gas; the pressure detecting means detects the pressure in the processing container; the plurality of first exhaust paths are connected to the processing container, and the first valve is provided; and the plurality of second exhaust paths are Connected to the processing container and provided with a second valve; an exhaust device connected to the first exhaust path or the second exhaust path; and a control unit based on the detected pressure detected by the pressure detecting device The first valve and the second valve are controlled so that the pressure in the processing container is set to a predetermined value, and the first valve variably adjusts the conduction of the first exhaust path. The valve is a valve for switching the switch of the second exhaust path, and the control unit includes an opening degree adjustment unit and a centralized adjustment point. It is provided to the opening degree of the first plurality of the exhaust path of the first valve; and a switching unit, are centrally disposed in the second plurality Switching of the switch of the second valve of the exhaust path. The vacuum apparatus according to claim 1, wherein one of the first exhaust passage and the second exhaust passage is connected to the exhaust device. The vacuum device according to claim 1 or 2, wherein the control unit sets the exhaust gas flow rate when the conduction is adjusted to V11 by the first valve in the first exhaust passage. In the first exhaust passage, when the exhaust gas flow rate when the opening degree of the first valve is fully opened is V12, and the exhaust gas flow rate of the second exhaust passage is V2, the following is satisfied. In the relationship of the formula (1), the degree of opening and closing of the first valve and the switch of the second valve are adjusted, n × V11 ≦ m × V2 ≦ n × V12 (1) (here, n indicates the foregoing 1 is the number of exhaust paths, and m is the number of the second exhaust paths). In the vacuum apparatus according to any one of the first to third aspects of the invention, the valve that variably adjusts the conduction of the second exhaust passage is used as the second valve, and only the switching operation is performed. The vacuum device according to any one of claims 1 to 4, wherein the vacuum device is an etching device that etches a target object. The vacuum device of claim 5, wherein the object to be processed is a substrate for FPD. A valve control method, which is a control method of a valve in a vacuum device In the vacuum device, the vacuum device includes a processing container that can accommodate the object to be processed and keeps the inside of the vacuum, and a gas supply source that supplies the processing gas to the processing container via the gas supply path; the flow rate adjusting device is a gas supply path is provided to adjust a supply flow rate of the processing gas; a pressure detecting device detects a pressure in the processing container; a plurality of first exhaust paths are connected to the processing container, and a first valve is provided; a plurality of second exhaust paths connected to the processing container and provided with a second valve; an exhaust device connected to the first exhaust path or the second exhaust path; and a control unit according to the pressure The detected pressure value and the set pressure value detected by the detecting device respectively control the first valve and the second valve such that the pressure in the processing container is set to a predetermined value, and the first valve is variably adjustable The valve for conducting the first exhaust passage, the second valve is a valve for switching a switch of the second exhaust passage, and the control unit includes a degree of opening and closing Section portion are provided on the focus adjusting degree of opening of the first plurality of the exhaust path of the first valve; and a switching unit, are centrally disposed in the second plurality In the switching of the switch of the second valve in the exhaust path, the method of controlling the valve includes a step of synchronizing and opening all of the second valves in synchronization, and detecting by the pressure detecting device The step of detecting the pressure value and the set pressure value, synchronizing and adjusting the opening degree of all of the aforementioned first valves. The method for controlling a valve according to the seventh aspect of the invention, wherein the first exhaust valve has a flow rate of the exhaust gas when the conduction is adjusted by the first valve, and is in the first row. In the gas path, when the exhaust gas flow rate when the opening degree of the first valve is fully opened is V12, and the exhaust gas flow rate of the second exhaust path is V2, the following formula (1) is satisfied. In the relationship, the opening degree of the first valve and the switch of the second valve are adjusted, n × V11 ≦ m × V2 ≦ n × V12 (1) (here, n indicates the first exhaust path The number of bars and m indicates the number of the second exhaust paths.