JP4927623B2 - Method of boosting load lock device - Google Patents

Description

The present invention relates to a boosting method b Dorokku device.

  For example, in a manufacturing process of an LCD substrate or the like, a so-called multi-chamber type processing system including a plurality of substrate processing apparatuses that perform predetermined processing such as CVD on a substrate in a reduced pressure atmosphere is used (for example, Patent Document 1). reference). Such a processing system includes a processing unit having a transfer chamber including a substrate transfer device for transferring a substrate and a plurality of substrate processing devices provided around the transfer chamber. A substrate is carried into and out of each substrate processing apparatus by a transfer arm of the substrate transfer apparatus. In addition, the processing system includes a loading / unloading unit for loading / unloading the substrate to / from the outside, and a load lock device is provided between the loading / unloading unit and the processing unit. The substrate loaded into the loading / unloading unit is loaded into the processing unit via the load lock device, processed by the processing unit, and then unloaded to the loading / unloading unit via the load lock device again.

  The load lock device is provided for the purpose of keeping the inside of the processing unit in a vacuum and not opening it to the loading / unloading unit side that is at atmospheric pressure. The board | substrate conveyed by the carrying in / out part is first accommodated in a load lock apparatus through the carrying in / out opening provided in the carrying in / out part side of the load lock apparatus. After the load lock device is depressurized and evacuated, the loading / unloading port provided on the processing unit side of the load lock device is opened and communicated with the transfer chamber. Then, the substrate is loaded by the transfer arm of the substrate transfer device. It is unloaded from the lock device and transferred to each substrate processing apparatus. Further, the substrate processed by each substrate processing apparatus is taken out by the transfer arm of the substrate transfer apparatus, and stored in the load lock apparatus through the load / unload port on the load / unload section side of the load lock apparatus. When the inside of the load lock device is pressurized and returned to atmospheric pressure, the loading / unloading port on the loading / unloading portion side of the load locking device is opened, and the substrate is returned to the loading / unloading portion.

  As such a load lock device, one having a heater for preheating a substrate in the load lock device is known (for example, refer to Patent Document 2). In addition, when the substrate is provided with a heating plate and a cooling plate and the substrate is carried into the processing unit from the loading / unloading unit, the substrate is heated by the heating plate, and when the substrate is unloaded from the processing unit to the loading / unloading unit, There has been proposed a cooling plate that can cool a substrate (see, for example, Patent Document 3).

  On the other hand, although it is not related to the load lock device, with respect to the semiconductor manufacturing device, when the processing chamber is pressurized and returned to atmospheric pressure, the atmospheric pressure is used to stabilize the pressure in the processing chamber after boosting, and then the atmosphere A method of opening is disclosed (for example, see Patent Document 4).

JP 2006-303013 A JP 2001-239144 A JP-T-2004-523880 JP-A-10-294283

  However, in the conventional load lock device, when the inside of the load lock device is at atmospheric pressure and the loading / unloading port on the loading / unloading portion side is opened, particles may enter the load locking device from the outside. It was. If particles that have entered the load lock device are brought into the processing section, the substrate processing may be adversely affected.

  On the other hand, as in Patent Document 4, it is possible to release the load lock device to the atmosphere after stabilizing the pressure in the processing chamber, but in this case, it is necessary to wait until the pressure in the processing chamber is stabilized. Therefore, there is a problem that the processing time becomes long and the throughput is not good.

An object of the present invention is to provide a method of boosting a load lock device that can effectively prevent particles from entering the load lock device and that can immediately release the chamber to the atmosphere after returning to atmospheric pressure. It is in.

According to the present invention, the chamber includes a chamber that can be decompressed to a vacuum state, an openable / closable loading / unloading port for loading / unloading the substrate into / from the chamber, and a temperature adjusting member that adjusts the temperature of the substrate in the chamber. A gas supply path for supplying gas therein, an exhaust path for exhausting the interior of the chamber, a vacuum pump for depressurizing the interior of the chamber to a vacuum state, and a vacuum pump connected to the chamber and supplied to the chamber A pressure-increasing method for a load-lock device having a leak path for discharging gas by a pressure difference from the outside, wherein a large-flow pipe is provided in the chamber that has been depressurized in a vacuum state with the loading / unloading port closed. A step of supplying gas to return to atmospheric pressure; and after returning to atmospheric pressure, the gas is further supplied into the chamber with a small flow pipe and the atmosphere in the chamber The has a leak step of discharging from the leak passage at a pressure difference between the outside and in the leak process, wherein the transfer port is opened, boosting method of the load lock device is provided.

  In this pressure increasing method, in the return step, gas is supplied into the chamber at a relatively large flow rate, for example, 600 to 100 liters / min, and in the leaking step, the gas is supplied at a relatively small flow rate, for example, 100 to 10 liters / min. A gas may be supplied into the chamber. In the leak process, the inside of the chamber is set to a gauge pressure of 1000 Pa or less, for example.

  According to the present invention, when the inside of the load lock device is opened to the atmosphere, the entry of particles into the load lock device can be effectively prevented by setting the inside of the chamber to a gauge pressure of 1000 Pa or less. . According to the present invention, after returning to atmospheric pressure, the atmosphere in the chamber is exhausted with a pressure difference from the outside while continuing to supply gas into the chamber, thereby substantially reducing the atmospheric pressure in the chamber. Can be kept equal. Therefore, even if the inside of the load lock device is released to the atmosphere immediately after returning to the atmospheric pressure, particles do not enter from the outside, and the inside of the load lock device can be kept clean. Therefore, it is not necessary to wait until the pressure is stabilized as in the conventional case, the processing time is shortened, and the throughput is improved.

  Hereinafter, an embodiment of the present invention includes a step of forming a thin film by plasma CVD (Chemical Vapor Deposition) processing on a glass substrate G for LCD (Liquid Crystal Display) as an example of a substrate. This will be described based on the processing system to be implemented. FIG. 1 is a plan view showing a schematic configuration of a processing system 1 including load lock devices 5 and 6 according to an embodiment of the present invention. FIG. 2 is a side view showing a schematic configuration of the processing system 1. A processing system 1 shown in FIG. 1 is a so-called multi-chamber processing system, and a loading / unloading unit 2 that loads / unloads a substrate G to / from the outside of the processing system 1, and a processing unit 3 that performs a CVD process on the substrate G, It has. Two load lock devices 5 and 6 are installed between the carry-in / out unit 2 and the processing unit 3. 1 and 2, the horizontal direction and the width direction of the carry-in / out section 2 (vertical direction in FIG. 1, the direction perpendicular to the drawing in FIG. 2) are the X direction and the horizontal plane direction. The arrangement direction of the unit 2, the load lock devices 5 and 6 and the processing unit 3 (the horizontal plane direction and the direction orthogonal to the X direction) is defined as the Y direction, and the vertical direction is defined as the Z direction. Further, in the present specification and the drawings, the same reference numerals are given to constituent elements having substantially the same functional configuration, and redundant description is omitted.

  The loading / unloading unit 2 is provided with a mounting table 11 on which a cassette C storing a plurality of substrates G is mounted, and a first transfer device 12 that transfers the substrates G. A plurality of cassettes C are arranged on the mounting table 11 along the X direction. In the cassette C on the mounting table 11, a plurality of substantially rectangular thin plate-like substrates G are stored side by side in a substantially horizontal posture.

  The transport device 12 is provided between the mounting table 11 and the load lock devices 5 and 6. The transport device 12 includes a rail 13 that extends along the X direction and a transport mechanism 14 that can move in the horizontal direction along the rail 13. The transfer mechanism 14 includes a pair of transfer arms 15 that place the substrate G and hold the substrate G substantially horizontally. The transfer arm 15 is moved up and down in the Z direction, moved in the Y direction, and in a substantially horizontal plane around the Z direction. Can be swiveled. That is, the transfer arm 15 is made to enter each cassette C through the opening 16 provided in front of each cassette C on the mounting table 11, and the substrates G are taken out from the cassette C one by one, or into the cassette C. It can be stored. Further, the transfer arm 15 enters the load lock devices 5 and 6 provided on the side facing the mounting table 11 with the transfer device 12 in between (the rear side of the transfer device 12 in the Y-axis direction), and the substrate G Can be carried into the load lock devices 5 and 6 one by one and unloaded from the load lock devices 5 and 6.

  As shown in FIG. 2, the load lock devices 5 and 6 are stacked one above the other. A gate valve 20 that opens and closes a loading / unloading port 52 of the load lock device 5 described later is provided on the loading / unloading unit 2 side of the lower load lock device 5. A gate valve 21 that opens and closes the carry-out port 53 of the load lock device 5 is provided. Similarly, a gate valve 22 for opening and closing a loading / unloading port 77 of the load lock device 6 to be described later is provided on the loading / unloading unit 2 side of the upper load lock device 6, and on the processing unit 3 side of the load lock device 6. Is provided with a gate valve 23 for opening and closing a carry-in port 76 of a load lock device 6 to be described later. In such a configuration, by closing the gate valves 20 and 22, the atmosphere in the loading / unloading unit 2 and the atmosphere in the load lock devices 5 and 6 can be blocked. Further, by closing the gate valves 21 and 23, the atmosphere of the processing unit 3 and the atmosphere in the load lock devices 5 and 6 can be blocked. The structure of each load lock device 5, 6 will be described in detail later.

  As shown in FIG. 1, the processing unit 3 contains a plurality of substrate processing apparatuses that house a substrate G and perform plasma CVD processing, for example, five substrate processing apparatuses 30 </ b> A to 30 </ b> E, and load lock apparatuses 5 and 6. A second transfer device 31 that transfers the substrate G to and from the substrate processing apparatuses 30A to 30E is provided. The second transfer device 31 is stored in a transfer chamber 33 provided in a transfer chamber 32 having a sealed structure. The transfer chamber 32 is provided adjacent to the load lock device 5. In addition, the load lock devices 5 and 6 and the substrate processing devices 30 </ b> A to 30 </ b> E are arranged so as to surround the periphery of the transfer chamber 32.

  The above-described gate valves 21 and 23 are provided between the transfer chamber 33 and the load lock devices 5 and 6, respectively, and the atmosphere in the transfer chamber 33 and the load lock devices 5 and 6 are respectively set by the gate valves 21 and 23. It is possible to block the atmosphere of each. Gate valves 35 are respectively provided between the transfer chamber 33 and the substrate processing apparatuses 30A to 30E. The gate valves 35 hermetically close the openings of the substrate processing apparatuses 30A to 30E. And the atmosphere in each of the substrate processing apparatuses 30A to 30E can be blocked. In addition, as shown in FIG. 2, an exhaust passage 36 is provided for forcibly exhausting the inside of the transfer chamber 33 to reduce the pressure. During processing in the processing system 1, the inside of the transfer chamber 33 and the substrate processing apparatuses 30 </ b> A to 30 </ b> E of the processing unit 3 is set to a reduced pressure atmosphere, for example, in a vacuum state, compared to the loading / unloading unit 2.

  The second transport device 31 includes, for example, a transport mechanism 40 having a multi-joint structure, and the transport mechanism 40 includes a pair of transport arms 41 that place the substrate G and hold the substrate G approximately horizontally. The transport mechanism 40 is capable of moving the transport arm 41 up and down in the Z direction, turning the transport arm 41 in a substantially horizontal plane around the Z direction, and moving the transport arm 41 back and forth in any direction within the horizontal plane. As a result, the transport mechanism 40 causes the transport arm 41 to enter the load lock devices 5 and 6 and the substrate processing apparatuses 30A to 30E via the gate valves 21, 23, and 35, and loads the substrates G one by one. And it is configured to be able to be carried out.

  Next, the configuration of the load lock devices 5 and 6 described above will be described. FIG. 3 is a longitudinal sectional view for explaining the internal structure of the load lock devices 5 and 6 cut along a cross section perpendicular to the X direction.

  First, the lower load lock device 5 includes a chamber 51 having a sealed structure. A loading / unloading port 52 for loading the substrate G into the chamber 51 is provided on the loading / unloading unit 2 side of the chamber 51, that is, on the left side in FIG. 3. The carry-in port 52 is provided with the gate valve 20 described above, and can be airtightly closed by the gate valve 20. On the processing unit 3 side of the chamber 51, that is, on the right side surface in FIG. 3, a carry-out port 53 for carrying the substrate G out of the chamber 51 is provided. The carry-out port 53 is provided with the gate valve 21 described above, and can be airtightly closed by the gate valve 21.

  A plurality of holding members 55 that support the substrate G are provided in the carry-out port 53. Each holding member 55 has a substantially rod shape and is provided so as to protrude upward from the bottom of the chamber 51. By placing the lower surface of the substrate G on the upper end of each holding member 55, the substrate G is supported substantially horizontally.

  Further, a heating plate 50 for heating the substrate G supported by the holding member 55 from below and an auxiliary heater 56 for heating from above are provided in the chamber 51. The heating plate 50 and the auxiliary heater 56 are connected to an AC power source 57, respectively, and are heated by electric power supplied from the AC power source 57, respectively.

  The auxiliary heater 56 has a substantially rectangular plate shape and is provided substantially horizontally along the ceiling of the chamber 51. The auxiliary heater 56 is opposed to the upper surface of the substrate G supported by the holding member 70 in a substantially parallel posture. The area of the lower surface of the auxiliary heater 56 is larger than the area of the upper surface of the substrate G and can be heated so as to cover the entire upper surface of the substrate G.

  The heating plate 50 has a substantially rectangular plate shape, and is provided substantially horizontally along the bottom surface of the chamber 51. The holding members 55 described above are respectively disposed in a plurality of holes 60 formed in the heating plate 50. The heating plate 50 faces the lower surface of the substrate G held by the holding member 55 in a substantially parallel posture.

  The heating plate 50 is configured to be movable up and down, and can be moved close to and away from the auxiliary heater 56. For example, as shown in FIG. 3, a cylinder 61 as an elevating mechanism is provided below the chamber 51, and a rod 62 connected to the cylinder 61 is provided so as to penetrate the bottom of the chamber 51 up and down. . The heating plate 50 is attached to the upper end portion of the rod 62. Then, by driving the cylinder 61, the rod 62 moves up and down in the Z-axis direction, so that the heating plate 50 moves up and down integrally with the rod 62 while moving each hole 60 along the holding member 55. ing.

  Furthermore, a plurality of support members 65 for supporting the substrate G during heating are provided on the upper surface of the heating plate 50. When the heating plate 50 is lowered to the standby position P <b> 1, the support member 65 is positioned below the upper end portion of the holding member 55. Therefore, even when the substrate G is held by the holding member 55, the support member 65 is not in contact with the substrate G. On the other hand, the support member 65 can be moved upward from the upper end of the holding member 55 by raising the heating plate 50 from the standby position P1. That is, the substrate G held by the holding member 55 can be lifted by the support member 65 and the substrate G can be supported by the support member 65. The support member 65 supports the substrate G substantially horizontally by placing the lower surface of the substrate G on the upper end portion of each support member 65. A gap having a substantially uniform width is formed between the lower surface of the substrate G supported by the support member 65 and the upper surface of the heating plate 50, and the substrate G and the heating plate 50 are arranged close to each other. Yes. When heating the substrate G, the heating plate 50 is raised to the heat treatment position P2, and in this state, the substrate G is supported by the plurality of support members 65, and is supported by the support member 65. The substrate G and the auxiliary heater 56 are close to each other, and a substantially uniform gap is formed between the upper surface of the substrate G supported by the support member 65 and the lower surface of the auxiliary heater 56 described above. ing.

In addition, a gas supply path 70 for supplying an inert gas such as N ₂ (nitrogen) gas or He (helium) gas and an exhaust path 71 for forcibly exhausting the chamber 51 are connected to the chamber 51. That is, the pressure in the chamber 51 can be adjusted by the gas supply from the gas supply path 70 and the forced exhaust by the exhaust path 71.

  Next, the configuration of the upper load lock device 6 will be described in detail. The load lock device 6 includes a chamber 75 having a sealed structure. In the illustrated example, the chamber 75 is placed on the upper surface of the chamber 51 of the lower load lock device 5.

  A loading port 76 for loading the substrate G into the chamber 75 is provided on the processing unit 3 side of the chamber 75, that is, on the right side in FIG. 3. The carry-in entrance 76 is provided with the gate valve 23 described above, and can be airtightly closed by the gate valve 23. A loading / unloading port 77 for unloading the substrate G from the chamber 75 is provided on the loading / unloading portion 2 side of the chamber 75, that is, on the left side in FIG. 3. The carry-out port 77 is provided with the gate valve 22 described above, and can be airtightly closed by the gate valve 22.

  A plurality of support members 80 for holding the substrate G are provided in the chamber 75. Each support member 80 is substantially rod-shaped and is provided so as to protrude upward from the bottom of the chamber 75. By placing the lower surface of the substrate G on the upper end of each support member 80, the substrate G is held substantially horizontally. It is supposed to be.

  Further, a cooling plate 81 and an auxiliary cooler 82 for cooling the substrate G are provided in the chamber 75. The cooling plate 81 and the auxiliary cooler 82 include cooling water supply paths 83 and 84 for supplying cooling water, respectively, and the cooling plate 81 and the auxiliary cooler are cooled by the cooling heat of the cooling water flowing through the cooling water supply paths 83 and 84. 82 is cooled.

  The auxiliary cooler 82 has a substantially rectangular plate shape, is provided substantially horizontally along the ceiling of the chamber 75, and is disposed on the upper surface side of the substrate G supported by the support member 80. Further, it is opposed to the upper surface of the substrate G supported by the support member 80 in a substantially parallel posture.

  In addition, the auxiliary cooler 82 is configured to be movable up and down, and can approach and separate from the substrate G supported by the support member 80. For example, as shown in FIG. 3, a cylinder 85 as an elevating mechanism is provided above the chamber 75, and a rod 86 of the cylinder 85 is provided so as to penetrate the ceiling of the chamber 75 vertically. The auxiliary cooler 82 is attached to the lower end portion of the rod 86. Then, by driving the cylinder 85, the rod 86 moves up and down in the Z-axis direction, so that the auxiliary cooler 82 moves up and down integrally with the rod 86. The auxiliary cooler 82 moves to, for example, an upper standby position P3 that is separated from the substrate G supported by the support member 80 and a lower cooling processing position P4 that is close to the substrate G. The area of the lower surface of the auxiliary cooler 82 is larger than the area of the upper surface of the substrate G, and cooling can be performed so as to cover the entire upper surface of the substrate G supported by the support member 80.

  The cooling plate 81 has a substantially rectangular plate shape, is provided substantially horizontally along the bottom surface of the chamber 51, and is disposed on the lower surface side of the substrate G supported by the support member 80. The above-described support members 80 are respectively disposed in the plurality of holes 90 formed in the cooling plate 81. The cooling plate 81 faces the lower surface of the substrate G supported by the support member 80 in a substantially parallel posture. Further, the substrate G and the cooling plate 81 are arranged close to each other in a state where a gap having a substantially uniform width is formed between the substrate G and the cooling plate 81. The area of the upper surface of the cooling plate 81 is larger than the area of the lower surface of the substrate G, and cooling can be performed so as to cover the entire lower surface of the substrate G supported by the support member 80.

Further, a gas supply path 91 for supplying an inert gas such as N ₂ (nitrogen) gas or He (helium) gas and an exhaust path 92 for forcibly exhausting the chamber 75 are connected to the chamber 75. That is, the pressure in the chamber 75 can be adjusted by the gas supply from the gas supply path 91 and the forced exhaust by the exhaust path 92.

FIG. 4 is an explanatory diagram of a supply / exhaust system for the load lock devices 5 and 6. Since the supply / exhaust system for the load lock devices 5 and 6 is the same, the supply / exhaust system for the load lock device 5 will be described as a representative. An inert gas supply source 100 pressurized to, for example, 0.7 MPa is connected to the upstream side of the gas supply path 70. The inert gas emitted from the supply source 100 is adjusted to 0.5 MPa by the pressure switch 101 and a regulator and is supplied into the chamber 51 of the load lock device 5. In the middle of the gas supply path 70, a large flow pipe 105 having a relatively large flow rate and a small flow pipe 106 having a relatively small flow rate are provided. The Cv value of the large flow pipe 105 is, for example, 0.6 to 0.1, and the Cv value of the small flow pipe 106 is, for example, 0.1 or less. In the case of gas, the Cv value can be obtained by the following equation.
Cv = 0.024 · Qg · (SG · T) ^−1/2 / ΔP
However, Qg: volume of gas flowing per minute (sccm), ΔP: absolute pressure on the primary side of the valve, unit (Pa), SG = 20 ° C 1 atm (100 kPa) air is 1 Specific gravity, T: temperature (K). The large flow pipe 105 and the small flow pipe 106 are provided with on / off valves 107 and 108. By opening / closing the on / off valves 107 and 108, an inert gas is passed through the large flow pipe 105, for example, 600 to By supplying an inert gas into the chamber 51 of the load lock device 5 at a relatively large flow rate such as 100 liters / min, and passing the inert gas through a specific small flow rate pipe 106 such as 100 to 10 liters / min, It is possible to switch to a state where an inert gas is supplied into the chamber 51 of the load lock device 5 at a relatively small flow rate. The small flow pipe 106 is provided with a needle valve 110. In the state where an inert gas is supplied into the chamber 51 at a relatively small flow rate through the small flow pipe 106, the needle valve 110 controls the flow rate. Can be adjusted.

  The exhaust path 71 is connected to an exhaust device 115 such as a vacuum pump. The exhaust passage 71 is provided with an automatic pressure control valve 116 that is a variable butterfly valve, and the pressure in the chamber 51 is controlled by the automatic pressure control valve 116.

  The chamber 51 is connected to a leak path 120 that discharges the atmosphere in the chamber 51 with a pressure difference from the outside. A check valve 121 is attached to the leak path 120. Since this check valve 121 is provided, air does not enter the chamber 51 through the leak path 120 from the outside.

  In addition, a pressure gauge 125 that detects the pressure in the chamber 51 and an accumulator 126 that absorbs an instantaneous pressure fluctuation in the chamber 51 are attached to the chamber 51. In addition, although the air supply / exhaust system with respect to the load lock apparatus 5 was demonstrated, the air supply / exhaust system with respect to the load lock apparatus 6 also has the same structure.

  Next, the processing steps for the substrate G in the processing system 1 configured as described above will be described. First, the carrier C in which a plurality of substrates G are stored is placed on the mounting table 11 with the opening 16 facing the transfer device 12 side. Then, the transfer arm 15 of the transfer device 12 is caused to enter the opening 16 and a single substrate G is taken out. The transfer arm 15 holding the substrate G is moved to a position facing the front of the gate valve 20 of the load lock device 5 arranged in the lower stage.

  On the other hand, in the load lock device 5, the carry-in port 52 and the carry-out port 53 are hermetically sealed by the closed gate valves 20 and 21, respectively, and the inside of the chamber 51 is sealed. As a result, the atmosphere in the loading / unloading unit 2 and the atmosphere in the transfer chamber 33 of the processing unit 3 are in a state of being blocked from each other via the load lock device 5. While the atmosphere of the carry-in / out section 2 is, for example, atmospheric pressure, the inside of the transfer chamber 33 is evacuated by the exhaust from the exhaust path 36.

  In the load lock device 5, first, the pressure in the chamber 51 is increased to a predetermined pressure, that is, substantially the same atmospheric pressure as the loading / unloading unit 2. In this case, first, the on-off valve 107 is opened in the gas supply path 70, and the inert gas of the supply source 100 is passed through the large flow pipe 105 to supply the inert gas into the chamber 51 at a relatively large flow rate. Perform a return process. As a result, the inert gas can be supplied at a large flow rate into the chamber 51 that has been decompressed, and the pressure in the chamber 51 can be instantaneously restored to atmospheric pressure.

  Next, after the inside of the chamber 51 is returned to the atmospheric pressure in this way, the on-off valve 107 is closed and the on-off valve 108 is opened, and an inert gas is passed through the small flow pipe 106 and supplied into the chamber 51 at a relatively small flow rate. To do. In addition, by opening the on-off valve 108 before closing the on-off valve 107 and closing the on-off valve 107 in a state in which the on-off valve 108 is opened in advance, it is possible to supply the chamber 51 at a relatively small flow rate. On the other hand, the atmosphere in the chamber 51 is discharged from the leak path 120 due to a pressure difference with the outside. In this way, the inert gas is continuously supplied into the chamber 51 at a relatively small flow rate, and the leak process is performed by exhausting the atmosphere in the chamber 51 from the leak path 120.

  In this leak process, the flow rate of the inert gas supplied into the chamber 51 is relatively small, and the atmosphere in the chamber 51 is discharged from the leak path 120 to the outside, so that the inside of the chamber 51 is substantially at atmospheric pressure. To be kept. In this case, it is preferable to adjust the needle valve 110 provided in the small flow pipe 106 so that the pressure in the chamber 51 becomes a gauge pressure of 1000 Pa or less.

  With the chamber 51 maintained at atmospheric pressure in this manner, the gate valve 20 is opened while the carry-out port 53 is closed by the gate valve 21, and the carry-in port 52 is opened. As a result, the inside of the chamber 51 is in communication with the atmosphere of the carry-in / out section 2 via the carry-in port 52. Even while the carry-in port 52 is opened, the vacuum state in the transfer chamber 33 can be maintained by closing the carry-out port 53 with the gate valve 21.

  Then, the transfer arm 15 holding the substrate G is moved in the Y-axis direction to enter the chamber 51 via the gate valve 20 and the carry-in port 52, and the substrate G is transferred from the transfer arm 15 onto the holding member 55. . After that, when the transfer arm 15 is withdrawn from the chamber 51, the gate valve 20 is closed, the chamber 51 is hermetically sealed, and the chamber 51 is forcibly exhausted by the exhaust passage 71. That is, the pressure is reduced to a vacuum state substantially equal to that in the transfer chamber 33. The chamber 51 may be depressurized while being supplied with an inert gas from the gas supply path 70, that is, the inside of the chamber 51 is purged with the inert gas. In this case, the heating of the substrate G is promoted. be able to.

  On the other hand, the substrate G accommodated in the chamber 51 is heated by the heating plate 50 and the auxiliary heater 56. First, the heating plate 50 is raised from the standby position P1 by driving the cylinder 61. Then, the substrate G is lifted from the holding member 55 by the support member 65 and is supported by the support member 65 while the heating plate 50 is raised. The substrate G supported by the support member 65 rises integrally with the heating plate 50 and is brought close to the auxiliary heater 56. Thus, the heating plate 50 is disposed at the heat treatment position P <b> 2, and the substrate G is heated by the heating plate 50 and the auxiliary heater 56. Thus, by heating the substrate G from both sides, the substrate G can be heated uniformly and can be efficiently heated in a short time.

  Note that the heating of the substrate G in the chamber 51 is preferably performed in parallel with the pressure reduction in the chamber 51. By doing so, the processing time in the chamber 51 can be shortened, which is efficient.

  When the inside of the chamber 51 is in a substantially vacuum state and the heating of the substrate G is completed, the gate valve 21 is opened while the carry-in port 52 is closed by the gate valve 20, and the carry-out port 53 is opened. As a result, the inside of the chamber 51 is in communication with the atmosphere of the transfer chamber 33 via the carry-out port 53. Even while the carry-out port 53 is opened, the vacuum state in the chamber 51 and the transfer chamber 33 can be maintained by closing the carry-in port 52 with the gate valve 20.

  The heating plate 50 is lowered from the heat treatment position P2 and returned to the standby position P1. Then, while the heating plate 50 is lowered, the holding member 55 comes into contact with the lower surface of the substrate G, and the substrate G is transferred from the support member 65 to the holding member 55. As a result, the substrate G is supported by the holding member 55.

  Thus, when the carry-out port 53 is opened and the heating plate 50 is placed at the standby position P1, the transfer arm 41 of the second transfer device 31 is moved in the Y-axis direction, and the gate valve 21 and the carry-out port 53 are moved. To enter the chamber 51. Then, the transfer arm 41 receives the substrate G from the holding member 55, and the transfer arm 41 holding the substrate G is withdrawn from the chamber 51. In this way, the substrate G is unloaded from the chamber 51 through the unloading port 53 and the gate valve 21 and loaded into the transfer chamber 33 of the processing unit 3.

  The substrate G carried into the transfer chamber 33 is transferred from the transfer chamber 33 to one of the substrate processing apparatuses 30A to 30E by the transfer arm 41, and film formation is performed by a predetermined plasma CVD process. In the substrate processing apparatuses 30A to 30E, the substrate G is heated in a reduced-pressure atmosphere, and a reaction gas is supplied into the processing chamber, and the reaction gas is turned into plasma by microwave energy. As a result, a predetermined thin film is formed on the surface of the substrate G. Here, since the loaded substrate G is preheated in the chamber 51, the heating time of the substrate G in the substrate processing apparatuses 30A to 30E can be shortened, and the substrate G can be processed efficiently.

  When the processing of the substrate G is completed in the substrate processing apparatuses 30 </ b> A to 30 </ b> E, the substrate G is taken out from the substrate processing apparatuses 30 </ b> A to 30 </ b> E by the transfer arm 41 and carried out to the transfer chamber 33. At this time, the substrate G is in a high temperature state.

  On the other hand, in the load lock device 6 arranged in the upper stage, the carry-in port 76 and the carry-out port 77 are hermetically sealed by the closed gate valves 23 and 22, respectively, so that the chamber 75 is sealed. Further, the inside of the chamber 75 is depressurized to a predetermined pressure, that is, substantially the same vacuum state as the transfer chamber 33 by forced exhaust of the exhaust path 92. In this state, the gate valve 23 is opened while the carry-out port 77 is closed by the gate valve 22, and the carry-in port 76 is opened. As a result, the inside of the chamber 75 communicates with the atmosphere of the transfer chamber 33 through the carry-in port 76. Even when the carry-in port 76 is opened, the vacuum state in the chamber 75 and the transfer chamber 33 can be maintained by closing the carry-out port 77 with the gate valve 22. Further, the auxiliary cooler 82 is raised by driving the cylinder 85 and waits at the standby position P3.

  When the carry-in port 76 is opened and the auxiliary cooler 82 is placed in the standby position P3, the transfer arm 41 holding the substrate G is moved in the Y-axis direction, and the chamber is passed through the gate valve 23 and the carry-in port 76. The substrate G is transferred from the transfer arm 41 onto the support member 80.

  In this way, the high-temperature substrate G unloaded from the substrate processing apparatuses 30 </ b> A to 30 </ b> E is loaded through the gate valve 23 and the loading port 76, stored in the chamber 75, and the transfer arm 41 leaves the chamber 75. Then, the gate valve 23 is closed and the inside of the chamber 75 is sealed. Then, an inert gas is supplied into the chamber 75 from the gas supply path 91 and the pressure in the chamber 75 is increased to a predetermined pressure, that is, approximately the same atmospheric pressure as that of the loading / unloading unit 2.

  Also in this case, first, the on-off valve 107 is opened in the gas supply path 91, and the inert gas from the supply source 100 is passed through the large flow pipe 105 to supply the inert gas into the chamber 75 at a relatively large flow rate. The return process by is performed. As a result, the inert gas can be supplied at a large flow rate into the chamber 75 that has been decompressed, and the pressure in the chamber 75 can be instantaneously restored to atmospheric pressure.

  Next, after the inside of the chamber 75 is returned to the atmospheric pressure in this way, the on-off valve 107 is closed and the on-off valve 108 is opened, and the inert gas is passed through the small flow pipe 106 and supplied into the chamber 75 at a relatively small flow rate. To do. On the other hand, the atmosphere in the chamber 75 is discharged from the leak path 120 due to a pressure difference with the outside. In this manner, the inert gas is continuously supplied into the chamber 75 at a relatively small flow rate, and the leak process is performed by exhausting the atmosphere in the chamber 75 from the leak path 120.

  In this leak process, the flow rate of the inert gas supplied into the chamber 75 is relatively small, and the atmosphere in the chamber 75 is discharged from the leak path 120 to the outside, so that the inside of the chamber 75 is substantially at atmospheric pressure. To be kept. In this case, it is preferable to adjust the needle valve 110 provided in the small flow pipe 106 so that the pressure in the chamber 75 becomes a gauge pressure of 1000 Pa or less.

  On the other hand, the substrate G is cooled by the auxiliary cooler 82 and the cooling plate 81. At the time of cooling, the auxiliary cooler 82 is lowered by driving the cylinder 85 and disposed at the cooling processing position P4 so as to be close to the upper surface of the substrate G. That is, the substrate G can be cooled uniformly by bringing the auxiliary cooler 82 close to the entire upper surface of the substrate G and the cooling plate 81 close to the entire lower surface to cool the substrate G from both sides. It can be cooled efficiently in time.

  Note that the cooling of the substrate G in the chamber 75 may be performed in parallel with the pressurization in the chamber 75. If it does so, the processing time in the chamber 75 can be shortened and it is efficient. Further, the cooling of the substrate G may be promoted by the cold air of the inert gas supplied from the gas supply path 91.

  When the cooling of the substrate G is completed, the gate valve 22 is opened and the carry-out port 77 is opened while the carry-in port 76 is closed by the gate valve 23 while the chamber 75 is maintained at atmospheric pressure. As a result, the inside of the chamber 75 communicates with the atmosphere of the carry-in / out section 2 via the carry-out port 77. Even while the carry-out port 77 is opened, the vacuum state in the transfer chamber 33 can be maintained by closing the carry-in port 76 with the gate valve 23.

  Then, the transfer arm 15 of the transfer device 12 is moved in the Y-axis direction and enters the chamber 75 through the gate valve 22 and the carry-out port 77. Then, the transfer arm 15 receives the substrate G from the support member 80, and the transfer arm 15 holding the substrate G is withdrawn from the chamber 75.

  Thus, the substrate G is unloaded from the chamber 75 through the unloading port 77 and the gate valve 22, and unloaded to the loading / unloading unit 2. Then, the carrier arm 15 returns the carrier C on the mounting table 11. As described above, a series of processing steps in the processing system 1 is completed.

  In such a processing system 1, when the chambers 51 and 75 of the load lock devices 5 and 6 are opened to the atmosphere, an inert gas is supplied into the chambers 51 and 75 that have been decompressed at a large flow rate, The pressure in the chambers 51 and 75 can be instantaneously restored to atmospheric pressure. Further, after returning to the atmospheric pressure, the atmosphere in the chambers 51 and 75 is discharged from the leak path 120 while continuing to supply the inert gas into the chambers 51 and 75 at a relatively small flow rate, thereby 51 and 75 can be kept substantially equal to the atmospheric pressure. In this case, for example, the inside of the chambers 51 and 75 can be maintained in a range of 1000 Pa or less in terms of gauge pressure. For this reason, even if the chambers 51 and 75 are immediately opened to the atmosphere after returning to the atmospheric pressure, particles do not enter from the outside, and the chambers 51 and 75 can be kept clean. As a result, there is no need to wait until the pressure is stabilized as in the conventional case, the processing time is shortened, and the throughput is improved.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  For example, the processing system may not be a multi-chamber type including a plurality of substrate processing apparatuses. The number of substrate processing apparatuses provided in the processing unit may be one. Moreover, although the processing system 1 which performs a plasma CVD process in the process part 3 was demonstrated in the above embodiment, the process performed in a process part may be another process. The present invention can be applied to a load lock apparatus provided in a processing system that performs other processing in a reduced pressure atmosphere, for example, thermal CVD processing, etching processing, ashing processing, and the like in a processing section. In the above embodiment, the case where the LCD substrate G is processed has been described. However, the substrate may be another substrate such as a semiconductor wafer.

  In the load lock device described with reference to FIG. 3, the pressure fluctuation in the chamber was examined. First, as shown in FIG. 5, an inert gas was supplied at a large flow rate of 450 SLM into the reduced pressure chamber, and the pressure in the chamber was increased to a positive pressure of about 8000 Pa from atmospheric pressure in about 120 seconds. . Thereafter, the inside of the chamber was sealed. The volume in the chamber (the volume without a temperature adjusting member such as a heating plate) is 230 liters. Then, after sealing, the pressure in the chamber gradually decreased. This is presumably because the inert gas supplied into the chamber was cooled and contracted after the supply. It was considered that the pressure in the chamber was stable when 67 seconds passed from the start of pressure increase.

  Next, as shown in FIG. 6, an inert gas is supplied into the reduced pressure chamber at a high flow rate of 600 SLM, and when the pressure in the chamber becomes almost atmospheric at around 340 seconds, The supply was stopped, and further, the atmosphere in the chamber was discharged with a pressure difference from the outside and leaked while the gas was continuously supplied into the chamber at a low flow rate of 5 SLM. The volume in the chamber (the volume without a temperature adjusting member such as a heating plate) is 230 liters. At time A when 30 seconds passed from the start of pressure increase, the pressure in the chamber was already 900 Pa gauge pressure, and the chamber could be opened.

  Next, when the inside of the chamber was opened to the atmosphere, the number of particles that entered the chamber was examined by the pressure difference between the inside of the chamber and the outside. The result is shown in FIG. When the inside of the chamber was in the range of −500 to 1000 Pa in gauge pressure, the number of particles entering the chamber was extremely small.

  The present invention can be applied to, for example, a load lock device of a processing system that processes a substrate.

It is a schematic plan view explaining the structure of a processing system. It is a schematic side view explaining the structure of a processing system. It is a schematic longitudinal cross-sectional view of a load lock apparatus. It is explanatory drawing of an air supply / exhaust system. It is a graph of the pressure fluctuation in a chamber at the time of raising the pressure to about 8000 Pa from atmospheric pressure to a positive pressure, and then sealing the inside of the chamber. 4 is a graph of pressure fluctuations in a chamber according to the present invention. It is a graph which shows the relationship between the differential pressure | voltage of the inside of a chamber, and the exterior, and the number of particles.

Explanation of symbols

G substrate 1 processing system 2 loading / unloading section 3 processing sections 5 and 6 load lock device 51 and 75 chamber 50 heating plate 56 auxiliary heater 70 and 91 gas supply path 71 and 92 exhaust path 81 cooling plate 82 auxiliary cooler 105 large flow pipe 106 Small flow pipe 110 Needle valve 115 Exhaust device 116 Automatic pressure control valve 120 Leakage path 125 Pressure gauge 126 Accumulator

Claims (2)

A chamber that can be depressurized in a vacuum state, an openable / closable loading / unloading port for loading / unloading the substrate into / from the chamber, and a temperature adjusting member for adjusting the temperature of the substrate in the chamber, and supplying gas into the chamber A gas supply path, a vacuum pump connected to an exhaust path for exhausting the interior of the chamber and depressurizing the interior of the chamber to a vacuum state, and a pressure connected to the chamber and the gas supplied into the chamber to the outside A pressure-boosting method for a load lock device having a leak path for discharging due to a difference,
  In a state where the loading / unloading port is closed, a return step of returning the gas to the atmospheric pressure by supplying a gas through a large flow pipe into the chamber that has been decompressed to a vacuum state;
  After returning to atmospheric pressure, it further has a leak process in which gas is continuously supplied into the chamber with a small flow pipe, and the atmosphere in the chamber is discharged from the leak path with a pressure difference from the outside,
  In the leak step, the loading / unloading opening is opened, and the method for boosting the load lock device is characterized. The method of boosting a load lock device according to claim 1, wherein in the leak step, the inside of the chamber is set to a gauge pressure of 1000 Pa or less.

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