JP2011040417A - Plasma processing apparatus and external air shielding vessel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a seal member for maintaining airtightness in a plasma processing apparatus from being deteriorated by plasma generated in the processing apparatus. <P>SOLUTION: An O-ring 10 is circularly provided on a contact surface between a protrusion 2a in a processing vessel 2 and a protrusion 3a in a lid 3. A plurality of gas flow inlets 12 through which an inert gas is allowed to flow into a gap 11 inside the O-ring 10 are formed on the protrusion 2a. The inert gas introduced through the gas flow inlet 12 flows into the inside of the processing vessel 2 while filling in the gap 11. The layer of the inert gas filled in the gap 11 can prevent the O-ring 10 from being deteriorated due to the plasma generated in the processing vessel 2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a plasma processing apparatus that performs plasma processing on a substrate, and an outside air blocking container in which a space in the container is blocked from outside air.

  For example, in a manufacturing process of an electronic device such as a semiconductor manufacturing apparatus, a liquid crystal display manufacturing apparatus, or an organic EL element, plasma is generated in a processing chamber using microwaves, and a film forming process or an etching process is performed on a substrate. Plasma processing is performed.

  Such plasma processing is usually performed in a plasma processing apparatus. The plasma processing apparatus has, for example, a processing container having an open top and a lid that closes the processing container. In the processing container, for example, a mounting table for mounting a substrate is provided. On the lower surface of the lid, for example, a slot antenna that generates microwaves is provided so as to face the substrate placed on the mounting table. The contact surface between the upper surface of the side wall of the processing container and the lower peripheral portion of the lid body is made of resin, for example, as a sealing material in order to maintain the airtightness in the processing container in a state where the upper side of the processing container is closed by the lid body. An O-ring is provided in an annular shape.

  When plasma processing is performed on the substrate, a predetermined gas (a rare gas for plasma excitation or a gas for plasma processing) supplied into the processing container by the energy of the microwave is turned into plasma, and a predetermined gas is applied to the substrate. Plasma processing is performed (Patent Document 1).

JP 2006-310794 A

  However, when performing plasma processing on a substrate using the above-described conventional plasma processing apparatus, the plasma generated in the processing container flows into a minute gap between the upper surface of the side wall of the processing container and the lower peripheral portion of the lid, and O The outer surface of the O-ring may deteriorate due to contact with the ring.

  This invention is made | formed in view of this point, and it aims at suppressing that the sealing material for maintaining the airtightness in a plasma processing apparatus deteriorates with the plasma which generate | occur | produced in the processing apparatus. .

  In order to achieve the above object, the present invention provides a plasma processing apparatus for performing plasma processing on a substrate, wherein an upper portion is opened, a processing container for accommodating and processing the substrate, and a lid for closing the processing container. And a sealing material provided annularly on the contact surface between the upper surface of the side wall of the processing container and the lower surface peripheral portion of the lid, and for maintaining airtightness in the processing container, A plurality of gas inlets for allowing an inert gas to flow into gaps existing inside the sealing material on the contact surface are formed on the upper surface of the side wall.

  According to the present invention, the sealing material is provided in an annular shape on the contact surface between the upper surface of the side wall of the processing container and the lower surface peripheral portion of the lid, and the inert gas is caused to flow into the gap formed inside the sealing material on the contact surface. Therefore, an annular inert gas layer can be formed between the inside of the processing container and the sealing material. The inert gas layer can suppress the plasma generated inside the processing container from flowing into the gap between the upper surface of the side wall of the processing container and the lower surface periphery of the lid, and the sealing material. It can suppress that it contacts. Therefore, deterioration of the sealing material due to plasma can be suppressed. Note that since the gas flowing into the gap formed inside the sealing material is an inert gas, even if this inert gas flows into the processing container, the plasma processing of the substrate performed in the processing container It does not affect.

  A container protrusion that protrudes outward along the outer periphery is formed at the upper end of the processing container, and a lid protrusion that protrudes outward along the outer periphery is formed at the lower end of the lid. An upper surface of the portion and a lower surface of the lid projecting portion are in contact with each other, and the plurality of gas inlets may be formed in the container projecting portion.

  The sealing material may be a resin O-ring.

  Another aspect of the present invention is an outside air blocking container in which a space in a container is blocked from outside air, the container having an airtight structure, and the space in the container communicates with the outside air. It has a gas communication path and a seal portion that blocks the gas communication path, and has a plurality of gas inlets that allow an inert gas to flow into the gas communication path on the container inner space side with respect to the seal portion. It is characterized by.

  The seal portion may include a resin O-ring.

  According to the present invention, an inert gas layer is formed between the inside of the processing container and the sealing material, and the plasma generated in the processing container is prevented from flowing into the gap between the contact surfaces of the processing container and the lid. And degradation of the sealing material due to plasma can be suppressed.

  Hereinafter, a preferred embodiment of the present invention will be described based on a plasma processing apparatus 1 that performs a CVD (Chemical Vapor Deposition) process, which is an example of a plasma process. FIG. 1 is an explanatory diagram showing a schematic configuration of a plasma processing apparatus 1 according to an embodiment of the present invention.

  As shown in FIG. 1, the plasma processing apparatus 1 includes, for example, a bottomed cylindrical processing container 2 having an open top, and a lid 3 that closes the top of the processing container 2. The processing container 2 and the lid 3 are made of aluminum, for example, and both are grounded.

  At the upper end of the side wall of the processing container 2, a container protruding portion 2 a that protrudes outward along the outer periphery is formed. At the lower end of the side surface of the lid 3, a lid protrusion 3 a that protrudes outward along the outer periphery is formed. In a state where the upper portion of the processing container 2 is closed by the lid 3, the upper surface of the container protruding portion 2a and the lower surface of the lid protruding portion 3a are in contact with each other. An O-ring 10 as a sealing material is provided in an annular shape on the contact surface between the container protrusion 2a and the cover protrusion 3a. For the O-ring 10, for example, a synthetic resin is used.

  As shown in FIG. 2, there is actually a very small gap between the container projecting portion 2a and the lid projecting portion 3a in the state where the upper portion of the processing container 2 is closed by the lid 3. Existing. For example, on the contact surface between the container protrusion 2a and the lid protrusion 3a, a gap 11 surrounded by the O-ring 10, the container protrusion 2a, and the lid protrusion 3a is formed inside the O-ring 10. A plurality of gas inlets 12 for allowing an inert gas such as argon gas or nitrogen gas to flow into the gap 11 are formed in the container protruding portion 2 a inside the O-ring 10. For example, as shown in FIG. 3, the gas inlet 12 is formed at four locations at equal intervals along the outer periphery of the container protrusion 2 a, and the inert gas flowing in from the gas inlet 12 fills the gap 11. However, it flows into the processing container 2. As shown in FIG. 2, a gas supply pipe 13 is connected to the gas inlet 12, and the gas supply pipe 13 communicates with an inert gas supply source 14 that supplies an inert gas to the gap 11.

  As shown in FIG. 1, a susceptor 20 as a mounting table for mounting the substrate G is provided inside the processing container 2. The susceptor 20 is made of, for example, aluminum nitride, and has a power supply unit 21 for electrostatically adsorbing the substrate G and applying a predetermined bias voltage to the inside of the processing container 2, and the substrate G at a predetermined temperature. A heater 22 for heating is provided. A high-frequency power supply 23 for bias application provided outside the processing container 2 is connected to the power supply unit 21 via a matching unit 23a including a capacitor, and a high-voltage DC power supply 24 for electrostatic adsorption is connected to a coil. 24a is connected. Similarly, an AC power supply 25 provided outside the processing container 2 is connected to the heater 22.

  An exhaust port 26 for exhausting the atmosphere inside the processing container 2 is provided at the bottom of the processing container 2. An exhaust pipe 28 communicating with an exhaust device 27 such as a vacuum pump is connected to the exhaust port 26. By exhausting from the exhaust port 26, the inside of the processing container 2 can be reduced to a predetermined pressure.

The lid 3 has a configuration in which, for example, a slot antenna 31 is attached to the lower surface of a lid body 30 made of aluminum, and a plurality of dielectrics 32 to be described later are attached to the lower surface of the slot antenna 31. The lid body 30 and the slot antenna 31 are integrally formed. The slot antenna 31 is made of, for example, aluminum, and each dielectric 32 is made of, for example, quartz glass, AlN, Al ₂ O ₃ , sapphire, SiN, ceramics, or the like.

A plurality of waveguides 33 are formed on the lower surface of the lid body 30. Each waveguide 33 is connected to a microwave supply device (not shown) provided outside the processing container 2. Then, for example, 2.45 GHz microwaves generated by the microwave supply device are introduced into the respective waveguides 33. The slot antenna 31 is formed with a plurality of slots 34 as microwave through holes. The slots 34 are formed at equal intervals along the waveguide 33 so as to be uniformly distributed over the entire lower surface of the lid body 30. Each waveguide 33 is filled with, for example, Al ₂ O ₃ , quartz, fluororesin, or the like.

  The plurality of dielectrics 32 attached to the slot antenna 31 are provided for each slot 34 so as to be uniformly distributed over the entire lower surface of the lid body 30. Each dielectric 32 is supported by a support member 35 provided in a lattice shape.

  Inside the lid body 30, a water channel 37 through which cooling water is circulated and supplied from a cooling water supply source 36 provided outside the processing container 2, and a gas supply source 40 similarly provided outside the processing container 2. A gas flow path 41 for supplying a predetermined gas is provided. In the present embodiment, an argon gas supply source 42, a silane gas supply source 43 as a processing gas, and a hydrogen gas supply source 44 are prepared as a gas supply source 40, and valves 42a, 43a, 44a, and mass flow controllers 42b, 43b are prepared. 44b and valves 42c, 43c, and 44c are connected to the gas flow path 41. The gas flow path 41 is provided along the support member 35 of the dielectric 32 and communicates with a plurality of gas ejection ports 45 formed in the support member 35. The gas outlets 45 are formed so as to be uniformly distributed over the entire lower surface of the lid body 30. A predetermined gas supplied from the gas supply source 30 is injected into the processing container 2 from the gas outlet 45.

  The plasma processing system 1 according to the present embodiment is configured as described above. Next, a film forming process performed in the plasma processing system 1 will be described. Here, a case where, for example, an amorphous silicon film is formed on the surface of the substrate G will be described as an example.

  First, the substrate G is placed on the susceptor 20 in the processing container 2. For example, when forming an amorphous silicon film, while supplying a predetermined gas, for example, a mixed gas of argon, silane, and hydrogen, from the gas supply source 40 through the gas flow path 41 and the gas injection port 45 into the processing container 2, By exhausting from the exhaust port 26, the inside of the processing container 2 is set to a predetermined pressure, for example, 10 Pa to 60 Pa. In this case, the predetermined gas is uniformly distributed over the entire surface of the substrate G placed on the susceptor 20 by ejecting the predetermined gas from the gas injection ports 45 that are distributed over the entire lower surface of the lid body 30. Can be supplied. The gas supplied into the processing container 2 is at room temperature.

  Simultaneously with the supply of a predetermined gas from the gas supply source 40 into the processing container 2, the gap 11 formed inside the O-ring 10 from the inert gas supply source 14 through the gas supply pipe 13 and the gas inlet 12. An inert gas is supplied inside. The inert gas supplied into the gap 11 flows out into the processing container 2 through the gas outlet 8. At this time, the inert gas is continuously supplied into the gap 11 and the gap 11 is filled with the inert gas. The plasma generated in the processing container 2 described later can be prevented from flowing into the gap 11 by the inert gas layer filled in the gap 11. At this time, the supply amount of argon gas supplied from the argon gas supply source 42 into the processing container 2 is controlled by, for example, the mass flow controller 42b based on the inflow amount of the inert gas flowing into the processing container 2. .

  In this way, a predetermined gas is supplied from the gas supply source 40 into the processing container 2, and an inert gas is supplied from the inert gas supply source 14 into the gap 11. For example, 250 ° C. to 300 ° C. Further, the side wall of the processing container 2 is heated to 150 ° C. to 180 ° C. so that gas decomposition products do not accumulate on the inner wall or the like of the processing container 2. Further, for example, a 2.45 GHz microwave generated by the microwave supply device is propagated from each waveguide 33 to each dielectric 32 through each slot 40. Thus, an electromagnetic field is formed in the processing container 2 by the energy of the microwaves propagated to each dielectric 32, and a predetermined processing gas supplied into the processing container 2 is turned into plasma, thereby forming a plasma on the substrate G. An amorphous silicon film is formed on the surface.

  According to the above embodiment, the O-ring 10 is annularly provided on the contact surface between the container projecting portion 2a of the processing container 2 and the lid projecting portion 3a of the lid 3, and the O-ring 10 is provided inside the O-ring 10 on this contact surface. Since the inert gas is allowed to flow into the formed gap 11, an annular inert gas layer can be formed between the inside of the processing container 2 and the O-ring 10. The inert gas layer can suppress the plasma generated inside the processing vessel 2 from flowing into the gap 11 between the upper surface of the side wall of the processing vessel 2 and the peripheral portion of the lower surface of the lid. , Contact with the O-ring 10 can be suppressed. Therefore, deterioration of the O-ring 10 due to plasma can be suppressed.

  In the above embodiment, the plasma processing apparatus 1 has been described. However, the present invention is an outside air shielding container in which the space in the container is shielded from the outside air, such as other vacuum containers or decompression containers and outside air blocking type cleaning devices. Thus, the present invention can also be applied to an outside air blocking container in which a corrosive or oxidizing gas such as ozone is present as a processing gas or vapor from a chemical solution inside the container. For example, the gas communication path is blocked by a gas communication path (gap on the contact surface between the container protrusion 2a and the lid protrusion 3a in FIG. 2) in which the inner space of the container (processing container 2 in FIG. 2) communicates with the outside air. A seal portion (O-ring 10 in FIG. 2) is provided. Further, a plurality of gas inlets (gas inlets 12 in FIG. 2) through which an inert gas flows is provided in the gas communication path (gap 11 in FIG. 2) on the container inner space side with respect to the seal portion. The gas communication path, the seal portion, and the gas inlet form an airtight structure. By such an airtight structure portion, an inert gas layer is formed between the inside of the container and the seal portion, and deterioration of the seal portion due to corrosive or oxidizing gas in the container or vapor from the chemical solution can be suppressed. .

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the ideas described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs. The present invention can also be applied to a substrate such as a semiconductor wafer, a liquid crystal display, an organic EL display, or a mask reticle for a photomask. Further, the present invention can be applied not only to a plasma processing apparatus that generates plasma on a substrate to form a film, but also to a plasma processing apparatus that performs etching on a substrate.

  The present invention is useful for a plasma processing apparatus that performs plasma processing on a substrate. Further, the present invention is an outside air blocking container in which the space in the container is blocked from outside air, such as other vacuum containers or decompression containers and outside air blocking type cleaning devices, and the inside of the container is corrosive or oxidative such as ozone It can be generally used for an outside air blocking container in which gas exists as a processing gas or as vapor from a chemical solution inside the container.

It is a top view which shows the outline of a structure of the plasma processing apparatus concerning this Embodiment. It is a longitudinal cross-sectional view which shows the outline of the structure of the contact surface vicinity of the container protrusion part and cover body protrusion part concerning this Embodiment. It is explanatory drawing which shows the outline of the planar structure of the container protrusion part concerning this Embodiment, and the flow of an inert gas.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma processing apparatus 2 Processing container 2a Container protrusion 3 Lid 3a Lid protrusion 10 O-ring 11 Crevice 12 Gas inlet 13 Gas supply pipe 14 Inert gas supply source

Claims (5)

A plasma processing apparatus for performing plasma processing on a substrate,
A processing container having an upper opening and accommodating and processing a substrate;
A lid for closing the upper side of the processing container;
A sealing material provided annularly on a contact surface between the upper surface of the side wall of the processing container and the lower surface peripheral portion of the lid, and for maintaining airtightness in the processing container;
The plasma processing apparatus according to claim 1, wherein a plurality of gas inlets for allowing an inert gas to flow into gaps existing inside the sealing material on the contact surface are formed on the upper surface of the side wall of the processing container. At the upper end of the processing container, a container protruding portion protruding outward along the outer periphery is formed,
At the lower end of the lid, a lid projecting portion that projects outward along the outer periphery is formed,
The upper surface of the container protrusion and the lower surface of the lid protrusion are in contact,
The plasma processing apparatus according to claim 1, wherein the plurality of gas inlets are formed in the container protrusion. The plasma processing apparatus according to claim 1, wherein the sealing material is a resin O-ring. An outside air blocking container in which the space inside the container is blocked from outside air,
The container has an airtight structure;
The airtight structure portion includes a gas communication path in which the inner space of the container communicates with outside air, and a seal portion that blocks the gas communication path, and the gas communication path on the inner space side of the container with respect to the seal portion. An outside air shut-off container having a plurality of gas inlets through which an inert gas is allowed to flow. The outside air shielding container according to claim 4, wherein the seal part includes a resin O-ring.

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