JP7378357B2 - Purging method for substrate processing equipment and gas supply piping - Google Patents

Description

The present disclosure relates to a substrate processing apparatus and a method for purging gas supply piping.

In substrate processing apparatuses, a corrosive processing gas is often supplied to a processing chamber through a supply piping in order to perform processing related to device formation. In a substrate processing apparatus, the lid of the processing chamber is opened during periodic maintenance, and the inside of the processing chamber is exposed to the atmosphere. At this time, the atmosphere also enters the supply piping communicating with the processing chamber, and the processing gas remaining in the supply piping reacts with moisture in the atmosphere to generate corrosive substances such as HCl. This corrosive substance corrodes the inside of the supply piping, causing particles. In order to suppress corrosion within the supply piping, it has been proposed to flow purge gas before opening the processing chamber lid to the atmosphere.

JP2017-092310A

The present disclosure provides a substrate processing apparatus and a gas supply piping purging method that can more safely open a processing chamber to the atmosphere while suppressing corrosion in the supply piping.

A substrate processing apparatus according to one aspect of the present disclosure includes a processing chamber, a gas supply pipe, a processing gas pipe, a purge gas pipe, and an interlocking opening. The processing chamber is a processing chamber in which a substrate is processed using a corrosive processing gas. The gas supply pipe is connected to the processing chamber and communicates with the inside of the processing chamber. The processing gas pipe is connected to the gas supply pipe via a first valve, and introduces the processing gas into the gas supply pipe. The purge gas piping is connected to the gas supply piping via the second valve on the processing chamber side of the first valve, and introduces the purge gas into the gas supply piping. The interlocking opening section opens the second valve in conjunction with the introduction of atmospheric air into the processing chamber while the first valve is closed.

According to the present disclosure, the processing chamber can be opened to the atmosphere more safely while suppressing corrosion in the supply piping.

FIG. 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus according to an embodiment of the present disclosure. FIG. 2 is a diagram showing an example of the configuration of the purge jig in this embodiment. FIG. 3 is a diagram showing an example of the purge flow rate for each shower plate. FIG. 4 is a flowchart illustrating an example of purge processing.

Embodiments of the disclosed substrate processing apparatus and gas supply piping purging method will be described in detail below based on the drawings. Note that the disclosed technology is not limited to the following embodiments.

During maintenance of substrate processing equipment, in order to suppress corrosion inside the supply piping, if purge gas is supplied into the supply piping before the processing chamber lid is opened to the atmosphere, the inside of the processing chamber becomes positive pressure, which prevents the processing chamber lid from being opened. At the same time, the purge gas inside may blow out all at once, which may be unfavorable from a safety standpoint. On the other hand, if purge gas is supplied into the supply piping after opening the lid of the processing chamber, the atmosphere may enter the supply piping, which may cause corrosion inside the supply piping. Therefore, it is expected to more safely open the processing chamber to the atmosphere while suppressing corrosion within the supply piping.

[Configuration of substrate processing apparatus 1]
FIG. 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus according to an embodiment of the present disclosure. The substrate processing apparatus 1 in this embodiment is, for example, a plasma processing apparatus, which generates inductively coupled plasma (ICP), and uses the generated plasma to perform etching, ashing, film formation, etc. on a rectangular substrate G. Perform plasma treatment. In this embodiment, the substrate G is, for example, a glass substrate for FPD (Flat Panel Display).

The substrate processing apparatus 1 includes a main body 10 and a control device 20. The main body 10 includes a rectangular cylinder-shaped airtight processing chamber 30 made of a conductive material such as aluminum whose inner wall surface is anodized. Processing chamber 30 is grounded. In the processing chamber 30, an upper lid 31 and a lower main body 32 are partitioned by a partition wall 31a having a plurality of shower plates 33. The partition wall 31a has a dielectric window or a metal window. A space surrounded by the partition wall 31a and the main body 32 becomes a processing chamber 32a. The lid 31 and the main body 32 are normally sealed, but can be separated at the A-A plane. During maintenance, the lid 31 side can be moved upward, for example, and separated, so that the inside of the main body 32 (processing chamber) can be separated. 32a) is opened to the atmosphere.

A gas supply pipe 34 is connected to each shower plate 33, respectively. Each gas supply pipe 34 is a pipe for introducing gas supplied from the outside of the processing chamber 30 into each shower plate 33. The gas supplied from the gas supply pipe 34 to the shower plate 33 is diffused in a diffusion chamber (not shown) within the shower plate 33, and is supplied from the gas discharge hole 33a to the processing chamber 32a.

The gas supply pipe 34 is connected to a processing gas pipe 36 via a first valve 35 . That is, the gas supply pipe 34 communicates from the outside of the processing chamber 30 to the shower plate 33 inside the processing chamber 30 . The processing gas piping 36 is connected to the processing gas supply section 40 via an FRC (Flow Ratio Controller) 37, a lid side valve 38, and a main body side valve 39. The FRC 37 distributes the flow rate determined by a flow rate controller such as an MFC (Mass Flow Controller) in the processing gas supply unit 40 to a predetermined ratio. That is, although not shown, the processing gas piping 36 is, for example, one until the lid-side valve 38, and branches into a plurality of processing gas piping 36 between the lid-side valve 38 and the FRC 37. Each branched processing gas pipe 36 is provided with an FRC 37 and a first valve 35, and each first valve 35 is connected to a respective gas supply pipe 34. Each gas supply pipe 34 is connected to a shower plate 33 located in a different region of the partition wall 31a, and by adjusting the gas distribution of each FRC 37, the supply distribution of the processing gas can be controlled. The lid-side valve 38 and the main body-side valve 39 are valves that are closed when the lid 31 is opened so that the processing gas piping 36 can be divided into the lid 31 side and the main body 32 side.

The processing gas supply unit 40 includes a gas supply source, a flow rate controller such as an MFC, and a valve. The flow rate controller controls the flow rate of the processing gas supplied from the gas supply source with the valve open, and supplies the processing gas with the controlled flow rate to the processing gas piping 36 . The processing gas is, for example, O2 gas, chlorine-based gas (corrosive gas) such as Cl2 gas, or BCl3 gas, or a mixed gas thereof. Further, the processing gas supply section 40 similarly supplies an inert gas such as N2 gas to the processing gas piping 36.

Each purge gas pipe 42 is connected to each gas supply pipe 34 on the shower plate 33 side of each first valve 35 via a second valve 41, respectively. Each purge gas pipe 42 is connected to a purge jig 44 via a flange 43. The second valve 41 switches between supplying and stopping the purge gas supplied from the purge gas pipe 42 to the gas supply pipe 34 . Further, the second valve 41 is an air-driven valve, and is connected to a driving pipe 49 via a mechanical valve 45 . The drive pipe 49 is connected to the purge jig 44. The flange 43 is for connecting each purge gas pipe 42 in a separable manner. Each purge gas pipe 42 can be divided at the flange 43 into a processing chamber 30 side and a purge jig 44 side. That is, the flange 43 is a maintenance gas port to which the purge jig 44 is connected and purge gas is supplied during maintenance.

The mechanical valve 45 is a valve whose opening and closing can be controlled by mechanical operation. Mechanical valve 45 has a valve section 46 and a detection section 47. The valve unit 46 controls opening and closing of the second valve 41 by switching supply/stop of the purge gas introduced from the drive piping 49. The detection unit 47 is a switch that controls opening and closing of the valve unit 46, and is provided on the lid 31 side. A block 48 for pressing down the detection section 47 is provided at a position on the main body 32 side facing the detection section 47 . When the lid 31 is closed, the detection section 47 is in contact with the block 48 and is pressed down, and the valve section 46 is closed. On the other hand, when the lid 31 is open (the lid 31 is detached from the main body 32), the detection section 47 is separated from the block 48 and is not pressed down, and the valve section 46 is open. In addition, although the valve part 46 and the detection part 47 are shown in separate positions in FIG. 1, the valve part 46 and the detection part 47 are integrated, and the valve part 46 and the detection part 47 are are mechanically connected. Note that the drive pipe 49 is separably connected to the mechanical valve 45.

The purge jig 44 is connected to a purge gas supply section 51 via a purge gas supply pipe 50. The purge gas supply section 51 includes a gas supply source, a flow rate controller such as an MFC, and a valve. The flow rate controller controls the flow rate of the purge gas supplied from the gas supply source with the valve open, and supplies the purge gas with the controlled flow rate to the purge gas supply piping 50. For example, dry air or the like can be used as the purge gas. Note that the purge jig 44 may be capable of supplying water vapor for cleaning the inside of the processing chamber 30.

Here, the purge jig 44 will be explained using FIG. 2. FIG. 2 is a diagram showing an example of the configuration of the purge jig in this embodiment. As shown in FIG. 2, the purge jig 44 includes, in order from the purge gas supply piping 50 side, a hand valve 52, a regulator 53, a plurality of flowmeters 55, a plurality of needle valves 56, and a plurality of filters 57. It is connected to each purge gas pipe 42 via a flange 43 outside the fixture 44. Further, a pipe 49a branches off from a pipe connecting between the hand valve 52 and the regulator 53, and is connected to a drive pipe 49 outside the purge jig 44. Further, the purge jig 44 is installed during maintenance when the lid 31 is opened, and each purge gas pipe 42 on the processing chamber 30 side is connected to each purge gas pipe 42 on the purge jig 44 side via a flange 43. Further, during maintenance, the drive pipe 49 is also connected to the mechanical valve 45. Note that the purge jig 44 may be installed as a part of the substrate processing apparatus 1 even in normal times.

The hand valve 52 is a valve that manually opens and closes the purge gas supplied from the purge gas supply section 51 via the purge gas supply piping 50. The hand valve 52 is opened by the operator after the purge jig 44 is installed and the connection between each purge gas pipe 42 and the drive pipe 49 is confirmed. The regulator 53 adjusts the pressure of the purge gas supplied to each purge gas pipe 42 . The pressure gauge 54 measures the pressure in the regulator 53. The piping 42a on the output side of the regulator 53 is branched and connected to a plurality of flowmeters 55, respectively. Each flow meter 55 measures the flow rate of purge gas output to each purge gas pipe 42 . The needle valve 56 adjusts the flow rate of each purge gas pipe 42. The filter 57 is a filter for removing particulates and the like from the purge gas.

Here, an example of the flow rate of the purge gas to each shower plate 33 will be explained using FIG. 3. FIG. 3 is a diagram showing an example of the purge flow rate for each shower plate 33. The gas supply pipe 34a shown in FIG. 3 is one extracted from the plurality of gas supply pipes 34. The gas supply pipe 34a further branches into a plurality of gas supply pipes 34b connected to each shower plate 33. In the example of FIG. 3, when purge gas is supplied to the gas supply pipe 34a at a rate of, for example, 52 L/min, the purge gas is equally distributed to each of the gas supply pipes 34b. Each gas supply pipe 34b supplies 6.5 L/min of purge gas to each shower plate 33. When dry air is used as the purge gas, if each shower plate 33 can be purged with dry air at a rate of 5 L/min or more, atmospheric air can be prevented from entering the gas supply pipe 34. Therefore, in the example of FIG. 3, corrosion within the gas supply pipes 34, 34a, 34b and the shower plate 33 can be suppressed.

Returning to the explanation of FIG. An antenna 60 is installed inside the lid 31. The antenna 60 is made of a highly conductive metal such as copper and is formed into an arbitrary shape such as a ring shape or a spiral shape. The antenna 60 is separated from the partition wall 31a by a spacer (not shown).

A high frequency power source 62 is connected to the antenna 60 via a matching box 61. The high frequency power supply 62 supplies high frequency power at a frequency of, for example, 13.56 MHz to the antenna 60 via the matching box 61. As a result, an induced electric field is formed within the processing chamber 32a below the antenna 60. The processing gas supplied from the shower plate 33 is turned into plasma by the induced electric field formed within the processing chamber 32a, and inductively coupled plasma is generated within the processing chamber 32a. High frequency power supply 62 and antenna 60 are examples of a plasma generation mechanism.

A mounting table 70 on which the substrate G is placed is arranged at the bottom of the main body 32. The mounting table 70 is formed into a square plate shape or a square column shape corresponding to the shape of the substrate G. An electrostatic chuck (not shown) for holding the substrate G is formed on the upper surface of the mounting table 70 on which the substrate G is placed. is fixed to the mounting table 70.

A matching box 71 and a high frequency power source 72 are connected to the mounting table 70 . The high frequency power supply 72 supplies high frequency power for bias to the mounting table 70 via the matching box 71. High frequency power supply 72 is an example of a bias power supply mechanism. Ions are drawn into the substrate G placed on the mounting table 70 by supplying high frequency power for bias to the mounting table 70 via the matching box 71 . The frequency of the high frequency power supplied to the mounting table 70 by the high frequency power supply 72 is, for example, in the range of 50 kHz to 10 MHz, and is, for example, 6 MHz. Further, although not shown, the mounting table 70 is provided with piping for supplying heat transfer gas, a temperature adjustment mechanism, a lift pin, and the like.

An opening and a gate valve (not shown) for loading and unloading the substrate G are provided on the side surface of the main body 32. Further, a plurality of exhaust ports 73 are formed on the outer peripheral side of the bottom of the main body 32 . A vacuum pump 76 is connected to each exhaust port 73 via an exhaust pipe 74 and an APC (Auto Pressure Controller) valve 75, respectively. The inside of the processing chamber 32a is evacuated by the vacuum pump 76, and the opening degree of the APC valve 75 is adjusted to maintain the pressure inside the processing chamber 32a at a predetermined pressure.

Control device 20 has a memory, a processor, and an input/output interface. The processor within the control device 20 controls each section of the main body section 10 via the input/output interface of the control device 20 by reading and executing a program stored in the memory within the control device 20 .

[How to purge gas supply piping]
Next, a method for purging gas supply piping in this embodiment will be described. FIG. 4 is a flowchart illustrating an example of purge processing. In FIG. 4, the explanation starts from a state in which the purge jig 44 is installed on the top of the lid 31, each purge gas pipe 42 and drive pipe 49 are connected to the processing chamber 30 side, and the purge gas supply pipe 50 is connected to the purge gas supply section 51. Start.

The control device 20 causes the processing gas supply unit 40 to supply N2 gas to the gas supply pipe 34 (step S1). N2 gas is introduced into the gas supply pipe 34 via the processing gas pipe 36 and the first valve 35. Next, the control device 20 closes the first valve 35 (step S2) and stops the supply of N2 gas. In other words, the processing gas pipe 36 is filled with N2 gas. Further, the control device 20 closes the lid side valve 38 and the main body side valve 39. Thereafter, the power to the substrate processing apparatus 1 is turned off by the operator. At this time, the purge jig 44 is in a state of supplying purge gas to each purge gas pipe 42 and drive pipe 49.

With the power of the substrate processing apparatus 1 turned off, the lid 31 is removed from the main body 32 by the operator, and the atmosphere is introduced into the processing chamber 30 . That is, the processing chamber 32a is opened to the atmosphere. The mechanical valve 45 detects detachment of the lid 31 from the main body 32 with the detection section 47, and opens the valve section 46. The second valve 41 is opened by the purge gas supplied when the valve portion 46 is opened. When the second valve 41 is opened, the purge gas in each purge gas pipe 42 is supplied to the gas supply pipe 34. That is, purge gas is supplied to the gas supply pipe 34 in conjunction with the opening of the processing chamber 30 to the atmosphere (step S3).

Since the purge gas supplied to the gas supply pipe 34 continues to be discharged from the gas discharge hole 33a of the shower plate 33, it is possible to prevent atmospheric air from entering the gas supply pipe 34 and suppress corrosion within the gas supply pipe 34. Can be done. In addition, since the supply of purge gas to the gas supply pipe 34 is started in conjunction with the opening of the processing chamber 30 to the atmosphere without human intervention, the inside of the processing chamber 30 does not become under positive pressure when it is opened to the atmosphere, making it safer. The processing chamber can then be vented to the atmosphere.

As described above, according to each embodiment, the substrate processing apparatus 1 includes the processing chamber 30, the gas supply pipe 34, the processing gas pipe 36, the purge gas pipe 42, and the interlocking opening part (mechanical valve 45). The processing chamber 30 is a processing chamber in which the substrate G is processed using a corrosive processing gas. The gas supply piping 34 is a piping connected to the processing chamber 30 and communicating to the inside of the processing chamber 30 . The processing gas piping 36 is connected to the gas supply piping 34 via a first valve 35 and introduces the processing gas into the gas supply piping 34 . The purge gas pipe 42 is connected to the gas supply pipe 34 via the second valve 41 on the processing chamber 30 side of the first valve 35, and introduces purge gas into the gas supply pipe 34. The interlocking opening section opens the second valve 41 in conjunction with the introduction of atmospheric air into the processing chamber 30 while the first valve 35 is closed. As a result, the processing chamber 30 can be opened to the atmosphere more safely while suppressing corrosion inside the gas supply pipe 34.

Further, according to the present embodiment, the processing chamber 30 is configured by the main body 32 and the lid 31 in a sealed manner. Furthermore, the atmospheric air is introduced into the processing chamber 30 by separating the lid 31 from the main body 32 . As a result, the processing chamber 30 can be opened to the atmosphere at the timing when the lid 31 is removed from the main body 32.

Further, according to the present embodiment, the interlocking opening section opens the second valve 41 based on the lid 31 being detached from the main body 32. As a result, purge gas can be supplied to the gas supply pipe 34 at the timing when the lid 31 is removed from the main body 32.

Further, according to the present embodiment, the interlocking opening section detects separation of the lid 31 from the main body 32 using the mechanical valve 45, and branches the purge gas piping 42 to supply the driving piping 49 connected to the mechanical valve 45. The second valve 41 is opened by the purge gas. As a result, purge gas can be supplied to the gas supply pipe 34 even when the power of the substrate processing apparatus 1 is turned off.

Further, according to this embodiment, the purge gas is dry air. As a result, corrosion within the gas supply pipe 34 can be suppressed. Furthermore, even if the purge gas is continuously supplied when the air is opened to the atmosphere, it will not affect the workers.

Further, according to the present embodiment, the method for purging the gas supply piping in the substrate processing apparatus 1 is such that the first gas supply piping is A step of closing the first valve 35 of the processing gas pipe 36 which is connected through the valve 35 of the gas supply pipe 36 and introduces the processing gas into the gas supply pipe 34; a step of opening the second valve 41 of the purge gas pipe 42 connected via the second valve 41 to the processing chamber 30 in conjunction with the introduction of the atmosphere into the processing chamber 30, and introducing the purge gas into the gas supply pipe 34; , has. As a result, the processing chamber 30 can be opened to the atmosphere more safely while suppressing corrosion inside the gas supply pipe 34.

In the above-described embodiment, an inductively coupled substrate processing apparatus has been described as an example of a plasma source, but a substrate processing apparatus equipped with another plasma source may be used. Examples of plasma sources other than inductively coupled plasma include capacitively coupled plasma (CCP), microwave excited surface wave plasma (SWP), electron cycloton resonance plasma (ECP), and helicon wave excited plasma (HWP). It will be done.

The embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

1 Substrate processing apparatus 10 Main unit 20 Control device 30 Processing chamber 31 Lid 31a Partition 32 Main body 32a Processing chamber 33 Shower plate 34 Gas supply piping 35 First valve 36 Processing gas piping 40 Processing gas supply section 41 Second valve 42 Purge gas Piping 43 Flange 44 Purge jig 45 Mechanical valve 49 Drive piping 50 Purge gas supply piping 51 Purge gas supply section 60 Antenna 61, 71 Matching box 62, 72 High frequency power supply 70 Mounting table G Substrate

Claims (6)

a processing chamber in which the substrate is processed with a corrosive processing gas;
a gas supply pipe connected to the processing chamber and communicating to the inside of the processing chamber;
a processing gas pipe connected to the gas supply pipe via a first valve and introducing the processing gas into the gas supply pipe;
a purge gas piping connected to the gas supply piping via a second valve on the processing chamber side of the first valve and introducing purge gas into the gas supply piping;
an interlocking opening section that opens the second valve in conjunction with introducing atmospheric air into the processing chamber when the first valve is closed;
A substrate processing apparatus having: The processing chamber is configured in a sealed manner by a main body and a lid,
The atmospheric air introduction includes introducing atmospheric air into the processing chamber by separating the lid from the main body.
The substrate processing apparatus according to claim 1. The interlocking opening section opens the second valve based on the lid being detached from the main body.
The substrate processing apparatus according to claim 2. The interlocking opening section detects detachment of the lid from the main body by a mechanical valve, and opens the second valve by a purge gas branched from the purge gas pipe and supplied to a driving pipe connected to the mechanical valve. to release,
The substrate processing apparatus according to claim 3. the purge gas is dry air;
A substrate processing apparatus according to any one of claims 1 to 4. A method for purging gas supply piping in a substrate processing apparatus, the method comprising:
The first processing gas pipe is connected via a first valve to a gas supply pipe connected to a processing chamber in which a substrate is processed with a corrosive processing gas, and the processing gas pipe introduces the processing gas into the gas supply pipe. a step of closing the first valve;
On the processing chamber side of the first valve, the second valve of the purge gas pipe connected to the gas supply pipe via a second valve is connected to the introduction of atmospheric air into the processing chamber. and introducing purge gas into the gas supply pipe;
A method for purging gas supply piping having

Images