JP2007073541A - Vacuum processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum processing device which can prevent mixing of moisture into a vacuum processing chamber certainly. <P>SOLUTION: Gate valves 30a and 30b having valve elements 31a and 31b, respectively, are arranged doubly between a vacuum processing chamber 10 and a load lock chamber 20. The load lock chamber 20 is connected with three exhaust pipes 21, 22 and 23 having different conductances which are connected with a vacuum pump 60 through open/close valves 62, 63 and 64, respectively. An N<SB>2</SB>gas supply 26 for introducing N<SB>2</SB>gas into the load lock chamber 20 is also connected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vacuum processing technique, and in particular, a vacuum processing apparatus for performing vacuum processing such as dry etching on a glass substrate for an FPD (flat panel display) represented by a liquid crystal display (LCD), a plasma display, or the like. The present invention relates to a technique that can be effectively applied to the above.

  For example, in an LCD manufacturing process, vacuum processing such as dry etching, sputtering, and CVD (chemical vapor deposition) is frequently used for an LCD glass substrate that is a substrate to be processed.

  In a vacuum processing apparatus that performs such vacuum processing, a vacuum preparatory chamber is provided adjacent to a vacuum processing chamber (process module) that is held in a vacuum and performs the above processing, and a vacuum is provided when a substrate to be processed is carried in and out. It has a structure that minimizes atmospheric fluctuations in the processing chamber.

  Specifically, for example, a load lock chamber having a role of an interface between the atmosphere side and the vacuum side is provided as a vacuum preparatory chamber between a cassette disposed on the atmosphere side and a vacuum processing chamber for performing an etching process or the like. It has been.

  In this load lock chamber, every time the substrate to be processed passes, the air release state and the exhaust to a high vacuum equivalent to the vacuum processing chamber are repeated. For this reason, a gate valve is provided between the load lock chamber and the vacuum processing chamber in which a vacuum state is always maintained to ensure airtightness of both chambers (for example, Patent Document 1).

  However, when the airtightness due to the gate valve is not sufficient, moisture in the atmosphere may leak into the vacuum processing chamber in the high vacuum state from the load lock chamber side in the atmosphere open state. When moisture is mixed into the vacuum processing chamber, there is a concern that even if it is in a very small amount, it adversely affects the vacuum processing such as etching and film formation, thereby reducing the reliability of manufactured products such as FPD.

In addition, as a conventional gate valve structure, a pair of sealing the opening of each chamber on both sides of the movable body in order to ensure airtightness between the vacuum processing chamber and the loading / unloading vacuum chamber (load lock chamber). There has also been proposed a gate valve provided with the valve body (for example, Patent Document 2). However, the gate valve of Patent Document 2 moves each valve body from the movable body in the opposite direction toward both the opening part of the vacuum chamber for loading and unloading on the atmosphere side and the opening part of the vacuum processing chamber. Since both openings are sealed at the same time, the loading / unloading vacuum chamber side valve element is pressed in the opposite direction to the differential pressure direction from the high pressure side to the low pressure side. There was a structural problem that the sealability of the part could not be sufficiently secured.
Japanese Patent Laying-Open No. 2005-12185 (FIG. 3 etc.) Japanese Patent Laid-Open No. 5-99348 (FIG. 1 etc.)

  As described above, when sufficient airtightness between the load lock chamber and the vacuum processing chamber cannot be ensured, air containing moisture from the load lock chamber side enters the vacuum processing chamber, which adversely affects the processing of the substrate to be processed. There are concerns to give.

  Even if the gate valve can be sealed, the load lock chamber is repeatedly opened to the atmosphere. If moisture contained in the atmosphere remains in the load lock chamber after exhaust, the gate valve There is a problem that the remaining moisture is transferred into the vacuum processing chamber when the substrate is opened and passed through the substrate to be processed. In particular, when the load lock chamber is exhausted at a high speed, moisture in the atmosphere tends to atomize and adhere to the inside of the load lock chamber as the pressure rapidly decreases, and this is evacuated through the gate opening. It becomes easy to mix in the processing chamber.

This invention is made | formed in view of this situation, Comprising: It aims at providing the vacuum processing apparatus which can prevent mixing of the water | moisture content into a vacuum processing chamber reliably.
That is, firstly, it is an object to provide a gate valve that can sufficiently ensure airtightness between a load lock chamber and a vacuum processing chamber. Another object of the present invention is to provide a technique capable of preventing moisture remaining and atomization in the process of exhausting the load lock chamber.

In order to solve the above problems, a first aspect of the present invention is to provide a vacuum processing chamber for performing predetermined processing on a substrate in a vacuum,
A vacuum preparatory chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the inside thereof is alternately held in an atmosphere open state and a vacuum state;
A double gate valve disposed between the vacuum processing chamber and the vacuum preparatory chamber;
A vacuum processing apparatus is provided.

  According to the first aspect, since the gate valve is doubled between the vacuum processing chamber and the vacuum preparatory chamber, the vacuum preparatory chamber and the vacuum processing chamber are reliably separated when the gate valve is closed. Thus, it is possible to reduce the mixing of moisture from the vacuum preparatory chamber that repeats the atmospheric state and the high vacuum state into the vacuum processing chamber as much as possible.

In the first aspect, a first gate valve that opens and closes an opening formed in the vacuum processing chamber;
A second gate valve disposed adjacent to the first gate valve and opening and closing an opening formed between the first gate valve;
It is preferable to comprise.
Further, it is preferable that the first gate valve and the second gate valve are opened and closed in synchronization.

  The first gate valve and the second gate valve press the valve body from the vacuum preparatory chamber side, which is relatively high in pressure, toward the vacuum processing chamber, which is low pressure. It is preferable. Thus, the valve body of each gate valve is pressed in the differential pressure direction at the time of sealing, that is, from the vacuum preparatory chamber on the atmospheric pressure side toward the vacuum processing chamber on the vacuum side, so that the sealing is surely performed. .

Further, it is preferable that an exhaust pipe for evacuating the inside of the valve container is connected to the first gate valve.
As a result, even when the vacuum preparatory chamber is opened to the atmosphere, the valve container of the first gate valve whose inside is depressurized to a predetermined pressure can be interposed between the vacuum preparatory chamber and the vacuum preparatory chamber. Air leakage from the chamber to the vacuum processing chamber can be more reliably prevented, and moisture can be prevented from entering the vacuum processing chamber.

Moreover, it is preferable that a plurality of exhaust pipes having different flow conductances are connected to the vacuum preliminary chamber.
Further, it is preferable that a purge gas supply source for introducing a purge gas is connected to the vacuum preliminary chamber.

A second aspect of the present invention is a vacuum processing chamber for performing a predetermined process on a substrate in a vacuum,
A vacuum preparatory chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the inside thereof is alternately held in an atmosphere open state and a vacuum state;
A plurality of exhaust pipes having different flow conductances connected to the vacuum preliminary chamber;
An exhaust means connected to the exhaust pipe for evacuating the vacuum preparatory chamber;
A vacuum processing apparatus is provided.

In the second aspect, the plurality of exhaust pipes are:
A first exhaust pipe;
A second exhaust pipe having a larger flow conductance than the first exhaust pipe;
A third exhaust pipe having a larger flow conductance than the second exhaust pipe;
It is preferable to comprise.

  In the vacuum processing apparatus according to the second aspect, by providing exhaust pipes having different flow conductances, it becomes possible to configure a plurality of patterns of exhaust paths by combining them. In the process of exhausting the vacuum preparatory chamber, by switching the exhaust path, it becomes possible to prevent water from being atomized due to a rapid pressure drop.

A third aspect of the present invention is a vacuum preparatory chamber in which a substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the interior thereof is alternately held in an open air state and a vacuum state. Is an exhaust method for exhausting to a vacuum state,
An exhaust method of the vacuum preliminary chamber, characterized in that exhaust speed is switched using a plurality of exhaust pipes connected to the vacuum preliminary chamber and having different flow conductances, and exhaust is performed by increasing the exhaust speed stepwise. provide.

  In the third aspect, when the vacuum preparatory chamber is exhausted to a vacuum state, the exhaust speed is switched using a plurality of exhaust pipes having different flow conductances, and exhaust is performed by gradually increasing the exhaust speed. It becomes possible to prevent water from being atomized due to a rapid pressure drop in the vacuum preparatory chamber.

  In the third aspect, it is preferable to switch the exhaust speed based on the pressure in the vacuum preliminary chamber. In addition, it is preferable that a purge gas is introduced into the vacuum preliminary chamber for a predetermined time while continuing to be exhausted when the vacuum preliminary chamber is reduced to a predetermined pressure.

According to a fourth aspect of the present invention, there is provided a vacuum preliminary chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the interior thereof is alternately held in an open air state and a vacuum state. An exhaust method for exhausting to the vacuum state,
Provided is a method for exhausting a vacuum preliminary chamber, wherein purge gas is introduced into the vacuum preliminary chamber for a predetermined time while continuing to be exhausted when the vacuum preliminary chamber is reduced to a predetermined pressure.

  According to the fourth aspect, by introducing the purge gas, the atmosphere in the vacuum preliminary chamber can be replaced with the purge gas under reduced pressure. As a result, moisture remaining in the vacuum preliminary chamber can be reliably removed.

A fifth aspect of the present invention is a vacuum preparatory chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the interior thereof is alternately held in an open air state and a vacuum state. Is a method for boosting the vacuum preliminary chamber for boosting from the vacuum state,
There is provided a method for boosting a vacuum preliminary chamber, wherein a purge gas is introduced at a predetermined flow rate when the vacuum preliminary chamber is opened to the atmosphere so that the vacuum preliminary chamber is set to a positive pressure in the open state.

  According to the fifth aspect, at the same time as the atmosphere is released, purge gas is introduced into the vacuum preliminary chamber at a predetermined flow rate to make the inside a positive pressure, thereby suppressing the entrance of the atmosphere from the clean room, and the moisture and particles are evacuated. It is possible to prevent entry into the spare room.

  According to the present invention, it is possible to reduce the mixing of moisture from the vacuum preparatory chamber that repeats the atmospheric state and the high vacuum state into the vacuum processing chamber as much as possible.

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.
FIG. 1 is a perspective view showing a schematic configuration of a vacuum processing apparatus 100 according to an embodiment of the present invention, and FIG. 2 is a horizontal sectional view showing a main part of the vacuum processing apparatus 100 of FIG. The vacuum processing apparatus 100 includes a vacuum processing chamber 10 that performs desired vacuum processing such as plasma etching processing and thin film formation processing on a substrate G such as a transparent LCD glass substrate in a vacuum atmosphere, and is connected to the vacuum processing chamber 10. The load lock chamber 20 functioning as a vacuum preparatory chamber, the gate valves 30a and 30b provided double between the vacuum processing chamber 10 and the load lock chamber 20, the load lock chamber 20 and the outside air side transfer A gate valve 40 that separates the mechanism 50 is provided.

  As shown in FIG. 2, the vacuum processing chamber 10 is connected to a vacuum pump 60 as an evacuation means via an exhaust control valve 61, so that the vacuum exhausting to a predetermined degree of vacuum processing of the substrate G is performed. Is possible. Further, a processing gas supply unit 12 is connected to the vacuum processing chamber 10 via a gas control valve 11, and a processing gas atmosphere having a predetermined pressure can be formed inside the vacuum processing chamber 10. . A processing stage 13 is provided inside the vacuum processing chamber 10 and a substrate G to be processed is placed thereon.

  Three exhaust pipes 21, 22 and 23 having different conductances are connected to the load lock chamber 20, and on-off valves 62, 63 and 64 are provided in the middle of the exhaust pipes 21, 22 and 23, respectively. ing. Each of the exhaust pipes 21, 22, and 23 is connected to a vacuum pump 60, and enables the inside of the load lock chamber 20 to be evacuated to a vacuum level equivalent to that of the vacuum processing chamber 10.

In addition, the load lock chamber 20, N ₂ gas supply source 26 for introducing the N ₂ gas as a purge gas through the gas control valve 25 is connected, in the interior of the load lock chamber 20, N ₂ gas It is configured to be able to introduce.

  As shown in the figure, the vacuum processing apparatus according to the present embodiment has a configuration in which gate valves 30 a and 30 b are doubled between the vacuum processing chamber 10 and the load lock chamber 20. The gate valve 30a has a valve body 31a that allows the vacuum processing chamber 10 and the load lock chamber 20 to communicate with each other and opens and closes an opening 90 (see FIG. 3; described later) having a size through which the substrate G can pass. . Similarly, the gate valve 30b also connects the vacuum processing chamber 10 and the load lock chamber 20 so that the substrate 94 supported by the substrate transfer apparatus 70 can pass through the opening 94 (see FIG. 3; described later). It has the valve body 31b which performs the opening / closing operation | movement. FIG. 2 shows a state in which both gate valves 30a and 30b are closed.

  Further, an exhaust pipe 27 is provided in the gate valve 30a provided on the vacuum processing chamber 10 side. The exhaust pipe 27 is connected to the vacuum pump 60, and an exhaust control valve 65 is provided in the middle thereof. By providing the exhaust pipe 27, the inside of the valve housing 95a of the gate valve 30a can be exhausted and reduced to a predetermined pressure with the gate valves 30a and 30b closed. In this way, by connecting the exhaust means to the gate valve 30a, the valve housing 95a can be connected to the vacuum processing chamber 10 even when the gate valves 30a and 30b are closed and the load lock chamber 20 is opened to the atmosphere. Since it becomes possible to interpose the gate valve 30a in which the entire interior of the chamber is decompressed, it is possible to more reliably prevent air leakage from the load lock chamber 20 to the vacuum processing chamber 10, and the vacuum processing chamber It is possible to prevent water from being mixed into 10.

  The gate valve 40 communicates with the load-lock chamber 20 and the outside atmosphere side, and an opening 41 having a size through which the substrate G supported by the atmosphere-side transport mechanism 50 can pass, and opening / closing of the opening 41 A valve element 42 for performing the operation is provided.

  Inside the load lock chamber 20, a substrate transfer device 70 is provided. The substrate transfer device 70 includes a base plate (not shown) fixed to the bottom of the load lock chamber 20 and a slide plate 74 that is stacked on the base plate and serves as a substrate support table on which the substrate G is placed. ing. The slide plate 74 is provided with a substantially U-shaped slide pick portion 74 a that supports the lower surface of the substrate G to be placed.

  The substrate transport apparatus 70 operates a drive motor (not shown) from the contracted state illustrated in FIG. 2, so that the slide plate 74 on which the substrate G is placed moves rightward toward the plane of the drawing. As a result, the substrate G supported by the slide pick portion 74 a is carried from the load lock chamber 20 toward the vacuum processing chamber 10. On the other hand, when the substrate G is unloaded from the vacuum processing chamber 10, the substrate G is received by the slide pick unit 74 a in the vacuum processing chamber 10, and then the drive motor (not shown) is reversed to be exemplified in FIG. 2. Degenerate state.

  Inside the load lock chamber 20, a substrate delivery mechanism 80 including a buffer plate 81 and a buffer plate 82 and a buffer raising / lowering mechanism (not shown) for raising and lowering the buffer plates 81 and 82 is provided at a position sandwiching the substrate transfer device 70. The peripheral portion of the substrate G placed on the slide plate 74 of the substrate transport apparatus 70 is supported from below by the buffer plates 81 and 82, and the substrate G is floated from the slide plate 74, and the atmosphere A substrate transfer operation such as an operation of lowering the substrate G received from the side transport mechanism 50 onto the slide plate 74 is performed.

  Referring to FIG. 1, the atmosphere-side transport mechanism 50 includes a transport arm 51 that can rotate and extend, and takes out an unprocessed substrate G from a substrate rack 55 in which a plurality of substrates G are stored. The operation of passing the substrate G to the substrate transfer device 70 in the load lock chamber 20 through the gate valve 40 and the processed substrate G from the substrate transfer device 70 in the load lock chamber 20 and the atmosphere side through the gate valve 40 Are taken out and stored in the substrate rack 55.

3 and 4 show cross-sectional structures of the gate valves 30a and 30b.
The gate valve 30 a opens and closes the substrate loading / unloading port 90 provided on the side wall 10 a of the vacuum processing chamber 10 from the load lock chamber 20 side. The gate valve 30a is a vertically extending valve body 31a so as to be able to close the opening 90 through which the substrate G can be loaded and unloaded in a horizontal posture, and a lift that supports the valve body 31a via a pair of cranks 32a and 33a. It has a horizontally long valve body 34a.

  The valve body 34a is connected to the piston rod 36a of the air cylinder 35a and is slidably guided by a guide rail 37a arranged vertically. That is, when the air cylinder 35a is operated to move the piston rod 36a up and down, the valve body 34a moves up and down in the vertical direction by the guide of the guide rail 37a.

  The cranks 32a and 33a are respectively suspended between the left side surface of the valve body 34a and the left side surface of the valve body 31a, and between the right side surface of the valve body 34a and the right side surface of the valve body 31a (note that 3 and 4, only the right side cranks 32a and 33a are shown). A roller 38a for avoiding friction with the ceiling portion 91a is attached to the upper surface of the valve body 31a.

  The gate valve 30b is disposed between the gate valve 30a and the load lock chamber 20, and opens and closes an opening 94 formed in a partition wall 92 that partitions the gate valve 30a and the gate valve 30b. 3 and 4, reference numeral 93 is an opening provided on the side wall of the load lock chamber 20 for loading and unloading the substrate G.

  The gate valve 30b has a valve body 31b formed in a horizontally long shape so that the opening 94 that allows the substrate G to be loaded and unloaded in a horizontal posture can be closed, and the valve body 31b via a pair of cranks 32b and 33b. And a horizontally long valve body 34b that can be moved up and down.

  The valve body 34b is connected to the piston rod 36b of the air cylinder 35b and is slidably guided by a guide rail 37b disposed vertically. Therefore, when the air cylinder 35b is operated to move the piston rod 36b up and down, the valve body 34b moves up and down in the vertical direction by the guide of the guide rail 37b.

  The cranks 32b and 33b are respectively suspended between the left side surface of the valve body 34b and the left side surface of the valve body 31b, and between the right side surface of the valve body 34b and the right side surface of the valve body 31b (note that 3 and FIG. 4, only the right side cranks 32b and 33b are shown). A roller 38b for avoiding friction with the ceiling portion 91b is attached to the upper surface of the valve body 31b.

  A working air supply source (not shown) distributes the working air evenly to the air cylinders 35a and 35b, the driving force of the air cylinder 35a is applied to the piston rod 36a, and the driving force of the air cylinder 35b is supplied to the piston rod 36b. It is configured to be transmitted. Accordingly, the valve bodies 31a and 31b of the gate valves 30a and 30b seal the opening 90 and the opening 94 in synchronization with each other or release the sealing. When the gate valves 30a and 30b are open, as shown in FIG. 3, the valve bodies 31a and 31b are in a standby position lower than the openings 90 and 94, and the valve bodies 34a and 34b are more than the valve bodies 31a and 31b. Is waiting at a lower standby position.

  When closing the gate valves 30a and 30b, the air cylinders 35a and 35b are operated from the state shown in FIG. 3 to advance the piston rods 36a and 36b by a predetermined stroke. Then, as shown in FIG. 4, the valve bodies 34a, 34b and the valve bodies 31a, 31b rise vertically from their original positions in parallel to each other, and the rollers 38a, 38b of the valve bodies 31a, 31b are connected to the ceiling surface 91a. 91b, and then the valve bodies 34a, 34b abut against the stoppers 39a, 39b.

  Then, the cranks 32a and 33a and the cranks 32b and 33b work to push the valve bodies 31a and 31b toward the openings 90 and 94 and push them around the opening 90 (side wall 10a) and around the opening 94 (partition wall 92). Hit it. In this operation, the rollers 38a and 38b roll in the horizontal direction on the ceiling surfaces 91a and 91b, so that the valve bodies 31a and 31b move in the horizontal direction to the walls around the openings 90 and 94 in the horizontal direction. Pressed against. Since a sealing member (not shown) such as an O-ring is attached around the openings 90 and 94, the valve bodies 31a and 31b are pressed against the openings 90 and 94 with high airtightness, respectively. The openings 90 and 94 can be sealed.

  When the gate valves 30a and 30b are opened from the closed state shown in FIG. 4, the air cylinders 35a and 35b are actuated to lower the piston rods 36a and 36b by the same stroke as in the forward movement, so that the sealing process The valve main bodies 34a and 34b and the valve bodies 31a and 31b are returned to their original standby positions by the reverse operation of the operation, and the sealing of the openings 90 and 94 is released.

  In the gate valves 30a and 30b shown in FIGS. 3 and 4, one system of operating air is evenly distributed to the air cylinders 35a and 35b, and the gate valves 30a and 30b are operated simultaneously. , 35b can be provided with a separate working air supply source to supply the working air, and the gate valves 30a, 30b can be individually operated with a certain time interval.

  Next, a processing procedure for the substrate G in the vacuum processing apparatus 100 of the present embodiment will be described. First, the substrate transfer apparatus 70 is brought into a contracted state in the load lock chamber 20, the valve bodies 31 a and 31 b of the gate valves 30 a and 30 b are closed, and the inside of the vacuum processing chamber 10 has a degree of vacuum required by the vacuum pump 60. Exhausted. In this state, the exhaust control valve 65 is opened, and the inside of the valve housing 95a of the gate valve 30a is evacuated through the exhaust pipe 27.

  The atmosphere-side transport mechanism 50 takes out the unprocessed substrate G from the substrate rack 55 by the transport arm 51, loads it into the load lock chamber 20 through the opening 41 of the gate valve 40, and slides 74 in the substrate transport device 70. Position directly above.

  Next, the buffer plates 81 and 82 rise and lift the peripheral portion of the substrate G from both sides, so that the substrate G floats from the transfer arm 51.

  Thereafter, the transfer arm 51 is pulled out to the atmosphere side and retracted to the outside of the load lock chamber 20, and then the buffer plates 81 and 82 are lowered, whereby the substrate G is moved to the slide plate 74 (slide pick unit) of the substrate transfer device 70. 74a) is moved on and placed.

  Then, the load lock chamber 20 is closed by closing the valve body 42 of the gate valve 40, opening one or more of the on-off valves 62, 63, 64 and operating the vacuum pump 60. After the inside is evacuated to a vacuum level similar to that of the vacuum processing chamber 10, the sealing of the openings 90 and 94 by the valve bodies 31a and 31b of the gate valves 30a and 30b is released. At this time, since the load lock chamber 20 is evacuated, the degree of vacuum and the atmosphere of the vacuum processing chamber 10 are not impaired.

  Next, through the openings 93, 90, 94, the slide plate 74 of the substrate transfer device 70 enters the inside of the vacuum processing chamber 10, and the substrate G is transferred directly above the processing stage 13 of the vacuum processing chamber 10, It is placed on the processing stage 13 via a push-up pin (not shown) provided in the vacuum processing chamber 10. Thereafter, the slide plate 74 is retracted into the load lock chamber 20 and retracted, the openings 90 and 94 are sealed by the valve bodies 31a and 31b of the gate valves 30a and 30b, and the vacuum processing chamber 10 is sealed.

  Thereafter, necessary gas is introduced from the processing gas supply unit 12 into the sealed vacuum processing chamber 10 to form a processing gas atmosphere, and the substrate G is subjected to necessary processing.

  After a predetermined time has elapsed, the introduction of the processing gas is stopped, and the valve bodies 31a and 31b of the gate valves 30a and 30b are lowered to release the sealing of the openings 90 and 94. Then, the slide plate 74 of the substrate transfer device 70 in the load lock chamber 20 is extended in multiple stages inside the vacuum processing chamber 10, and the processed substrate G in the vacuum processing chamber 10 is moved in the reverse procedure to the above-described loading operation. The slide plate 74 is degenerated by moving from the processing stage 13 onto the slide plate 74 and is carried out into the load lock chamber 20. Thereafter, the openings 90 and 94 are closed by the valve bodies 31a and 31b of the gate valves 30a and 30b, and the vacuum processing chamber 10 is sealed. Further, similarly to the above, the exhaust control valve 65 is opened and the inside of the valve housing 95a of the gate valve 30a is evacuated through the exhaust pipe 27.

Thereafter, the exhaust of the load lock chamber 20 is stopped, the buffer plates 81 and 82 are raised, and the peripheral portions of the substrate G are supported and floated, and the pressure adjustment lines 28 and 29 (see FIG. 5) described later are used. After gradually introducing N ₂ or the like to a pressure close to the atmosphere, the valve body 42 of the gate valve 40 is opened, and the transfer arm 51 of the atmosphere-side transfer mechanism 50 is inserted below the floating substrate G. In this state, the substrate G is moved to the transfer arm 51 by lowering the buffer plates 81 and 82.

  Then, by pulling the transfer arm 51 to the atmosphere side, the processed substrate G is carried out from the load lock chamber 20 to the atmosphere side and stored in the substrate rack 55.

  In the vacuum processing apparatus 100 having the above configuration, since the gate valves 30a and 30b are provided in a double manner, the load lock chamber 20 and the vacuum processing chamber 10 are reliably separated when the gate valves 30a and 30b are closed. In addition, it is possible to reduce the mixing of moisture from the load lock chamber 20 to the vacuum processing chamber 10 that repeats the atmospheric state and the high vacuum state as much as possible.

  Further, the valve bodies 31a and 31b of the gate valves 30a and 30b are pressed in the differential pressure direction at the time of sealing, that is, from the load lock chamber 20 on the atmospheric pressure side toward the vacuum processing chamber 10 on the vacuum side. Sealing by 31a and 31b is ensured.

  Further, since the exhaust pipe 27 for evacuating the inside of the valve housing 95a of the gate valve 30a is provided, the inside of the load lock chamber 20 is kept at a predetermined pressure with the vacuum processing chamber 10 even when the load lock chamber 20 is opened to the atmosphere. It becomes possible to interpose the valve housing 95a of the decompressed gate valve 30a, and more reliably prevent air leakage from the load lock chamber 20 to the vacuum processing chamber 10, and the moisture to the vacuum processing chamber 10 can be prevented. Mixing can be prevented.

  Next, with reference to FIG. 5 and FIG. 6, a procedure for exhausting the gas and replacing the gas in the load lock chamber 20 for more reliably preventing moisture from entering the vacuum processing chamber 10 will be described. FIG. 5 schematically shows a schematic configuration of the exhaust path and the purge gas supply path of the load lock chamber 20. As described above, the exhaust pipes 21, 22, and 23 having different conductances are connected to the load lock chamber 20. Specifically, each exhaust pipe 21, 22, 23 is provided with an orifice (throttle portion) (not shown) in the middle thereof, and the exhaust pipes 21, 22, 22 are made different in diameter. The flow conductance of 23 is adjusted. In addition, you may adjust so that it may become desired conductance by changing the diameter of each exhaust pipe 21,22,23.

  An open / close valve 62 is provided in the middle of the exhaust pipe 21, an open / close valve 63 is provided in the middle of the exhaust pipe 22, and an open / close valve 64 is provided in the middle of the exhaust pipe 23. The exhaust pipes 21, 22, and 23 are connected to a mechanical booster pump (MBP) 60a and a dry pump (DP) 60b (vacuum pump 60) so that the inside of the load lock chamber 20 can be evacuated.

In addition, the load lock chamber 20, through the N ₂ gas supply line 24 is connected N ₂ gas supply source 26, so as to supply the N ₂ gas as a purge gas into the load lock chamber 20 .
The load lock chamber 20 is also connected to the N ₂ gas supply source 26 through the pressure adjustment line 28 having a large conductance and the pressure adjustment line 29 having a small conductance, and the opening / closing valve 65 and the opening / closing valve 66 are connected to each other. By switching and gradually introducing N ₂ gas, it is possible to suppress an abrupt increase in pressure when the load lock chamber 20 in a vacuum state is opened to the atmosphere.

The exhaust pipe 21 functions as an exhaust path for high-speed exhaust with the largest channel conductance. The exhaust pipe 23 is an exhaust pipe line having a smaller channel conductance than the exhaust pipe 21, and the exhaust pipe 22 is an exhaust pipe line having a smaller channel conductance than the exhaust pipe 23. By providing these exhaust pipes 21, 22, and 23 and combining opening and closing of the on-off valves 62, 63, and 64, a plurality of exhaust path patterns can be created. For example, in this embodiment, the orifice diameter of the exhaust pipe 21 is 40 mm, the orifice diameter of the exhaust pipe 22 is 10 mm, and the orifice diameter of the exhaust pipe 23 is 15 mm. Note that the number of exhaust pipes is not limited to three. For example, when the number of exhaust pipes is n, (2 ⁿ −1) pattern exhaust paths can be created by combination.

In the present embodiment, when the on-off valves 62 and 64 are closed and the on-off valve 63 is opened, exhaust is performed by the exhaust pipe 22 having a minimum opening diameter of 10 mm. Is referred to as an "exhaust path".
Further, when the on-off valves 62 and 63 are closed and the on-off valve 64 is opened, exhaust is performed by the exhaust pipe 23 having a minimum opening diameter of 15 mm, so that the flow conductance is a little more than the first exhaust path by the exhaust pipe 22. Is a large exhaust path (referred to as “second exhaust path”).

When the on-off valve 62 is closed and the on-off valve 63 and the on-off valve 64 are opened, the sum of the minimum opening diameters of the exhaust pipe 22 and the exhaust pipe 23 is 25 mm (10 mm + 15 mm). An exhaust path (referred to as a “third exhaust path”) having a slightly larger flow conductance than the exhaust path is configured.
Further, in a state where the on-off valves 63 and 64 are closed and only the on-off valve 62 is opened, the exhaust pipe 21 having a minimum opening diameter of 40 mm is exhausted, so that a high-speed exhaust path (“fourth” (Referred to as “exhaust path”).

  As described above, by arranging the exhaust pipes 21, 22, and 23 having different flow conductances and switching the opening and closing of the valves 62, 63, and 64, a plurality of patterns of exhaust paths can be configured. In the process of exhausting the load lock chamber 20, it is possible to prevent the atomization of moisture due to a rapid pressure drop by switching the first to fourth exhaust paths. For this reason, it is preferable to switch the exhaust path in the exhaust process using the pressure in the load lock chamber 20 as an index. For example, in the process of exhausting from the atmospheric pressure of 101325 Pa (760 Torr) and exhausting the inside of the load lock chamber 20, water atomization tends to occur up to approximately 26664 Pa (200 Torr). In the process, it is preferable to avoid high speed exhaust through the fourth exhaust path.

  FIG. 6 shows a preferred example of a procedure for exhausting the inside of the load lock chamber 20 to a high vacuum state after opening the atmosphere. The pressure value for switching from the first exhaust path to the fourth exhaust path is not limited to the following example and can be set as appropriate. Further, instead of the pressure, for example, switching from the first exhaust path to the fourth exhaust path may be performed based on time.

First, in step S11, in a state where the gate valve 40 is opened and the load lock chamber 20 is opened to the atmosphere, simultaneously with the release of the atmosphere, the gas control valve 25 is opened as necessary, and the N ₂ at a predetermined flow rate is placed in the load lock chamber 20. Purge the gas. Thereby, since the inside of the load lock chamber 20 becomes a positive pressure, entry of air from the clean room is suppressed, and moisture and particles can be prevented from entering the load lock chamber 20. The gate valves 30a and 30b are closed.
Next, in step S12, the gate valve 40 is closed and the load lock 20 is closed from the atmosphere open state.

  Next, in step S13, the on-off valves 62 and 64 are closed, the on-off valve 63 is opened, the mechanical booster pump (MBP) 60a and the dry pump (DP) 60b are operated, and the load lock chamber 20 is operated by the first exhaust path. Exhaust inside. The exhaust in step S13 is performed until the pressure in the load lock chamber 20 drops to, for example, about 79992 Pa (600 Torr).

  When the pressure in the load lock chamber 20 decreases to about 79992 Pa (600 Torr), for example, after 3 seconds, the on-off valve 63 is closed from the state of Step S13, the on-off valve 64 is opened, and exhaust is performed through the second exhaust path (Step S13). S14). The exhaust in step S14 is performed until the pressure in the load lock chamber 20 drops to, for example, about 53328 Pa (400 Torr).

  When the pressure in the load lock chamber 20 decreases to about 53328 Pa (400 Torr), for example, after 5 seconds, the on-off valve 63 is further opened from the state of step S14 to switch to the third exhaust path and exhaust is performed (step S15). . The exhaust in step S15 is performed until the pressure in the load lock chamber 20 drops to, for example, about 26664 Pa (200 Torr).

  When the pressure in the load lock chamber 20 decreases to about 26664 Pa (200 Torr), for example, after 1 second, the on-off valves 63 and 64 are closed from the state of step S15, only the on-off valve 62 is opened, and the fourth exhaust path is switched to high speed. Exhaust is performed (step S16). The evacuation in step S16 is performed until the pressure in the load lock chamber 20 drops from about 26664 Pa (200 Torr) to a predetermined high vacuum state.

  As described above, in steps S13 to S16, the moisture in the atmosphere is easily atomized in the exhaust process by switching from the first exhaust path to the fourth exhaust path according to the pressure in the load lock chamber 20. In the pressure-decreasing process up to about (200 Torr), the exhaust speed is gradually increased from the slow exhaust, and at about 26664 Pa (200 Torr) or less where moisture atomization is less likely to occur, the load lock chamber is shifted to high speed exhaust. The moisture in 20 can be removed reliably, and mixing of moisture into the vacuum processing chamber 10 can be prevented.

Then, when the exhaust in step S16 proceeds and the pressure in the load lock chamber 20 reaches 53.328 Pa (400 mTorr), the gas control valve 25 is opened and a predetermined flow rate, for example, 6000 to 8000 mL / min, preferably 7000 mL. N ₂ gas is introduced into the load lock chamber 20 at / min (step S17). The flow rate of the N ₂ gas to be introduced can be set according to the exhaust capacity of the vacuum pump 60, but it is preferable to set the flow rate as illustrated above from the partial pressure ratio between air and N ₂ . This N ₂ gas purge is performed to finally remove the moisture remaining in the load lock chamber 20 by substituting the atmosphere in the load lock chamber 20 with N ₂ under reduced pressure. The N ₂ gas purge is preferably performed for a predetermined time, for example, 15 to 30 seconds, preferably about 23 seconds, until the pressure in the load lock chamber 20 reaches, for example, 13.332 Pa (100 mTorr).

By evacuating the load lock chamber 20 while switching the first to fourth exhaust paths in the procedure from step S13 to step S16, and performing the N ₂ gas purge in step S17, The inside of the load lock chamber 20 can be depressurized to a high vacuum state while suppressing the atomization and residual of water. Accordingly, after evacuating the load lock chamber 20 in this manner, the gate valves 30a and 30b are opened, and when the substrate G is transferred to and from the vacuum processing chamber 10, moisture to the vacuum processing chamber 10 is discharged. Can be reliably prevented.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the idea of the present invention.
For example, in the above-described embodiment, a vacuum processing apparatus for processing an LCD substrate as a substrate has been described as an example. However, the present invention is not limited to this, and a vacuum processing apparatus for processing other FPD substrates or semiconductor wafers may be used. In addition to the liquid crystal display (LCD), the FPD includes a light emitting diode (LED) display, an electro luminescence (EL) display, a fluorescent display tube (VFD), a plasma display panel (PDP), and the like. Is exemplified.

  Moreover, in the said embodiment, although it was set as the structure which arrange | positions the three exhaust pipes 21,22,23 from which flow path conductance differs in the load lock chamber 20, it can also be set as the structure which arranges four or more.

  Moreover, in the said embodiment, although the vacuum processing apparatus 100 of the structure by which the vacuum preliminary chamber 20 was arrange | positioned adjacent to the vacuum processing chamber 10 was mentioned as an example, it demonstrated, between a vacuum processing chamber and a vacuum preliminary chamber. In addition, the present invention can be applied to a vacuum processing apparatus in which a vacuum transfer chamber is disposed.

  The present invention can be suitably used for a vacuum processing apparatus including a vacuum processing chamber and a vacuum preliminary chamber.

The perspective view which shows the external appearance of the vacuum processing apparatus which concerns on one Embodiment of this invention. The horizontal sectional view which shows the vacuum preliminary | backup chamber and vacuum processing chamber in the vacuum processing apparatus of FIG. The schematic sectional drawing which shows the state which the gate valve opened. The schematic sectional drawing which shows the state which the gate valve closed. Drawing which shows the outline of the gas exhaust system and gas introduction system of a load lock room. The flowchart which shows the exhaust procedure of a load lock chamber.

Explanation of symbols

10 ...... vacuum processing chamber 20 ...... load lock chambers 21, 22, 23 ...... exhaust pipe 24 ...... _{N 2} gas supply line 26 ...... _{N 2} gas supply source 27 ...... exhaust pipe 30a, 30b, 40 ...... gate Valve 50 ... Air-side transfer mechanism 60 ... Vacuum pump 70 ... Substrate transfer device 74 ... Slide plate 74a ... Slide pick unit 80 ... Substrate delivery mechanism 81, 82 ... Buffer plate 100 ... Vacuum processing device G ……substrate

Claims (14)

A vacuum processing chamber for performing predetermined processing on the substrate in vacuum;
A vacuum preparatory chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the inside thereof is alternately held in an atmosphere open state and a vacuum state;
A double gate valve disposed between the vacuum processing chamber and the vacuum preparatory chamber;
A vacuum processing apparatus comprising: A first gate valve for opening and closing an opening formed in the vacuum processing chamber;
A second gate valve disposed adjacent to the first gate valve and opening and closing an opening formed between the first gate valve;
The vacuum processing apparatus according to claim 1, comprising:   The vacuum processing apparatus according to claim 2, wherein the first gate valve and the second gate valve open and close in synchronization.   The first gate valve and the second gate valve press the valve body from the vacuum preparatory chamber side, which is relatively high in sealing, to the vacuum processing chamber side, which is low pressure. The vacuum processing apparatus according to claim 3, wherein the vacuum processing apparatus is characterized.   The vacuum processing apparatus according to claim 2, wherein an exhaust pipe for evacuating the inside of the valve container is connected to the first gate valve.   The vacuum processing apparatus according to claim 1, wherein a plurality of exhaust pipes having different flow conductances are connected to the vacuum preliminary chamber.   The vacuum processing apparatus according to any one of claims 1 to 6, wherein a purge gas supply source for introducing a purge gas is connected to the vacuum preliminary chamber. A vacuum processing chamber for performing predetermined processing on the substrate in vacuum;
A vacuum preparatory chamber in which the substrate is temporarily accommodated in the process of being carried into and out of the vacuum processing chamber, and the inside thereof is alternately held in an atmosphere open state and a vacuum state;
A plurality of exhaust pipes having different flow conductances connected to the vacuum preliminary chamber;
An exhaust means connected to the exhaust pipe for evacuating the vacuum preparatory chamber;
A vacuum processing apparatus comprising: The plurality of exhaust pipes are
A first exhaust pipe;
A second exhaust pipe having a larger flow conductance than the first exhaust pipe;
A third exhaust pipe having a larger flow conductance than the second exhaust pipe;
The vacuum processing apparatus according to claim 8, comprising: In the process of temporarily storing the substrate in the process of being carried in and out of the vacuum processing chamber, the vacuum preliminary chamber in which the inside is alternately held in the atmosphere open state and the vacuum state is evacuated to the vacuum state. There,
An evacuation method for a vacuum preliminary chamber, wherein the exhaust speed is switched using a plurality of exhaust pipes having different flow conductances connected to the vacuum preliminary chamber and the exhaust speed is increased stepwise.   The method of exhausting a vacuum preliminary chamber according to claim 10, wherein the exhaust speed is switched based on the pressure in the vacuum preliminary chamber.   The vacuum preliminary chamber according to claim 10 or 11, wherein when the vacuum preliminary chamber is depressurized to a predetermined pressure, purge gas is introduced into the vacuum preliminary chamber for a predetermined time while evacuation is continued. Exhaust method. In the process of temporarily storing the substrate in the process of being carried in and out of the vacuum processing chamber, the vacuum preliminary chamber in which the inside is alternately held in the atmosphere open state and the vacuum state is evacuated to the vacuum state. There,
A method of exhausting a vacuum preparatory chamber, wherein purge gas is introduced into the vacuum preparatory chamber for a predetermined time while evacuation is continued when the vacuum preparatory chamber is depressurized to a predetermined pressure. A vacuum preparatory chamber that temporarily holds the substrate in the process of being carried into and out of the vacuum processing chamber, and that boosts the vacuum preparatory chamber in which the inside is alternately held in an open air state and a vacuum state from the vacuum state Boosting method,
A method for boosting a vacuum prechamber, wherein a purge gas is introduced at a predetermined flow rate when the vacuum prechamber is opened to the atmosphere so that the vacuum prechamber is brought to a positive pressure in an open state.

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