WO2023008039A1 - Substrate processing device and substrate processing method - Google Patents

Abstract

Provided is a technology capable of expanding the size of a plasma reactor and improving uniformity of substrate processing. This substrate processing device is provided with a substrate holding unit (3), a plurality of guards (7), a plasma reactor (1), a first elevator mechanism (15), and a second elevator mechanism (75). The substrate holding unit (3) holds a substrate (W). The plurality of guards (7) have a cylindrical shape surrounding the substrate holding unit (3), and are provided concentrically. The plasma reactor (1) is provided vertically upward of the substrate holding unit (3), and extends outward of the peripheral edges of the substrate as seen in a plan view. The plasma reactor (1) radiates a plasma onto the substrate (W) in a processing state in which the plurality of guards (7) are positioned at a lower position where an upper end (711) of an inner circumferential surface of the outermost guard (7A) is vertically downward of an upper surface of the substrate (W), and the plasma reactor (1) is positioned at a plasma processing position in close proximity to the substrate (W).

Description

SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD

The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Conventionally, substrate processing apparatuses that irradiate plasma onto substrates have been proposed (for example, Patent Documents 1 and 2). In Patent Document 1, a substrate processing apparatus includes a spin chuck that rotates a substrate in a horizontal position, a plasma nozzle that irradiates the upper surface of the substrate with plasma, a processing liquid nozzle that discharges a processing liquid onto the upper surface of the substrate, and each nozzle. It includes a nozzle moving part that moves, a guard that receives the processing liquid that scatters from the periphery of the substrate, and a guard elevating part that elevates the guard.

In Patent Document 1, the substrate processing apparatus discharges the processing liquid from the processing liquid nozzle onto the upper surface of the rotating substrate while the guard is raised to form a liquid film of the processing liquid on the upper surface of the substrate. The substrate processing apparatus irradiates the entire surface of the substrate with plasma by reciprocating the plasma nozzle along the upper surface of the rotating substrate. As a result, the substrate can be dried while suppressing pattern collapse.

JP 2020-181892 A JP 2004-165636 A

In order to properly irradiate the substrate with plasma, it is desirable to bring the plasma reactor closer to the substrate. This is because when the plasma reactor is separated from the substrate, plasma or active species disappear before reaching the substrate.

Also, in order to irradiate the substrate with plasma more uniformly, it is desirable to arrange a flat plasma reactor so as to face the upper surface of the substrate. This is because such flat plasma can irradiate the upper surface of the substrate with plasma over a wide range.

However, in the flat plasma reactor, it was found that the temperature at the periphery is significantly lower than the temperature at the center. Therefore, even if a flat plasma reactor is designed with a size that can irradiate the entire upper surface of the substrate with plasma, the temperature at the periphery of the substrate may be significantly lower than the temperature at the center. In this case, the degree of processing on the substrate varies due to the temperature difference.

In order to solve this problem, if the size of the plasma reactor in plan view is further increased, the plasma reactor may interfere with the guard.

Therefore, an object of the present disclosure is to provide a technology capable of improving the uniformity of processing on a substrate by enlarging the size of the plasma reactor.

A first aspect of a substrate processing apparatus includes a substrate holding portion that holds a substrate, a plurality of guards that have a cylindrical shape surrounding the substrate holding portion and are concentrically provided, and a guard that is perpendicular to the substrate holding portion. A plasma reactor that is provided above and spreads outside the peripheral edge of the substrate held by the substrate holding part in a plan view, and moves the plasma reactor up and down relative to the substrate holding part. A first elevating mechanism and a second elevating mechanism for relatively elevating the plurality of guards with respect to the substrate holding portion, wherein the upper end of the inner peripheral surface of the outermost guard among the plurality of guards is positioned above the substrate. in a processing state in which the plurality of guards are positioned vertically below the upper surface of the plasma reactor and the plasma reactor is positioned at a plasma processing position close to the substrate; to irradiate.

A second aspect of the substrate processing apparatus is the substrate processing apparatus according to the first aspect, wherein in the processing state, the distance between the plasma reactor and the outermost guard is equal to the outermost guard and the substrate. It is narrower than the interval with the holding part.

A third aspect of the substrate processing apparatus is the substrate processing apparatus according to the second aspect, wherein the plasma reactor abuts against the guard in the vertical direction in the processing state.

A fourth aspect of the substrate processing apparatus is the substrate processing apparatus according to the third aspect, wherein the lower surface of the portion of the plasma reactor outside the peripheral edge of the substrate and the upper surface of the outermost peripheral guard are At least one of them is provided with an elastic sealing member that is in close contact with the other.

A fifth aspect of the substrate processing apparatus is the substrate processing apparatus according to the second aspect, wherein the lower surface of the portion outside the peripheral edge of the substrate in the plasma reactor is, in the processing state, the outermost peripheral guard. A labyrinth structure having irregularities in the radial direction is formed together with the upper surface of the .

A sixth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the outer portion of the plasma reactor outside the peripheral edge of the substrate protrudes downward. The inner diameter of the outer portion is larger than the diameter of the substrate, and the lower surface of the outer portion is lower than the upper surface of the substrate held by the substrate holder in the processing state. Located in

A seventh aspect of the substrate processing apparatus is the substrate processing apparatus according to the sixth aspect, wherein the inner diameter of the outer portion of the plasma reactor is equal to or smaller than the upper opening diameter of the outermost guard.

An eighth aspect of the substrate processing apparatus is the substrate processing apparatus according to the sixth or seventh aspect, wherein the substrate holding part includes a spin base facing the substrate vertically below the substrate, The inner diameter of the outer portion is larger than the diameter of the spin base.

A ninth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the sixth to eighth aspects, wherein the plasma reactor includes an electrode assembly to which power for plasma is supplied, and the outer A portion supports the electrode assembly from below.

A tenth aspect of the substrate processing apparatus is the substrate processing apparatus according to any one of the first to ninth aspects, wherein a processing liquid is supplied to the main surface of the substrate held by the substrate holding part. The substrate holder includes a rotation mechanism that rotates the substrate around a rotation axis extending in a vertical direction, and the second elevating mechanism moves at least the outermost guard with respect to the substrate holder. The nozzle discharges the processing liquid, the substrate holding part rotates the substrate, and the upper position is such that the upper end is vertically above the upper surface of the substrate. position.

According to a first aspect of the substrate processing method, a substrate holding part is provided at a holding step for holding a substrate and a position facing the upper surface of the substrate held by the substrate holding part, and is positioned outside the substrate in plan view. A lighting step for lighting the spreading plasma reactor, and a guard having a cylindrical shape surrounding the substrate holding portion and having an upper end of an outermost guard among a plurality of concentrically provided guards held by the substrate holding portion. a moving step of positioning the guard with respect to the substrate holder at a lower position lower than the substrate, and moving the plasma reactor to a plasma processing position close to the upper surface of the substrate; Prepare.

A second aspect of the substrate processing method is the substrate processing method according to the first aspect, wherein the moving step relatively moves at least the outermost guard to the lower position with respect to the substrate holding part. and a plasma moving step of relatively moving the plasma reactor to the plasma processing position with respect to the substrate holder after the guard moving step.

A third aspect of the substrate processing method is the substrate processing method according to the first aspect, wherein the moving step relatively moves at least the outermost guard to the lower position with respect to the substrate holding part. and a plasma moving step of relatively moving the plasma reactor to the plasma processing position with respect to the substrate holder in parallel with the guard moving step.

According to the first aspect of the substrate processing apparatus and the first aspect of the substrate processing method, the guard can be positioned vertically below the plasma reactor in the processing state. Therefore, the size of the plasma reactor in plan view can be designed to be large without depending on the guard. Therefore, the plasma reactor can irradiate the substrate with plasma with the central portion of the plasma reactor having a relatively uniform temperature facing the entire surface of the substrate, thereby improving the uniformity of the substrate processing.

According to the second aspect of the substrate processing apparatus, the atmosphere between the plasma reactor and the substrate passes through the gap between the guard and the substrate holder more easily than the gap between the plasma reactor and the guard, and is exhausted to the outside through the exhaust part. easy to be That is, it is possible to prevent the atmosphere from flowing out of the guard through the gap between the plasma reactor and the guard.

According to the third aspect of the substrate processing apparatus, it is possible to further suppress the atmosphere from flowing out of the guard.

According to the fourth aspect of the substrate processing apparatus, it is possible to further suppress the atmosphere from flowing out of the guard.

According to the fifth aspect of the substrate processing apparatus, gas is allowed to flow into the guard from the outside of the guard through the gap between the plasma reactor and the outermost guard while suppressing the atmosphere from flowing out of the guard. be able to. Therefore, the atmosphere between the plasma reactor and the substrate can be replaced with a clean atmosphere.

According to the sixth aspect of the substrate processing apparatus, the outer portion can function as a guard.

According to the seventh aspect of the substrate processing apparatus, the atmosphere that flows vertically downward along the inner peripheral surface of the outer peripheral edge portion does not easily collide with the upper surface of the guard, and easily passes through the gap between the guard and the substrate holding portion.

According to the eighth aspect of the substrate processing apparatus, the atmosphere flowing vertically downward along the inner peripheral surface of the outer peripheral portion is less likely to collide with the upper surface of the spin base, and easily passes through the gap between the guard and the substrate holding portion. .

According to the ninth aspect of the substrate processing apparatus, the outer portion that supports the electrode assembly can function as a guard. Therefore, the manufacturing cost of the plasma reactor can be reduced compared to the case where a member functioning as a guard is separately provided in the plasma reactor.

According to the tenth aspect of the substrate processing apparatus, the guard can catch the processing liquid scattered from the periphery of the substrate.

According to the second aspect of the substrate processing method, collision between the plasma reactor and the guard can be suppressed.

According to the third aspect of the substrate processing method, throughput can be improved.

It is a top view which shows roughly an example of a structure of a substrate processing apparatus. 4 is a block diagram schematically showing an example of the internal configuration of a control unit; FIG. 3 is a diagram schematically showing an example of a configuration of a processing unit according to the first embodiment; FIG. 1 is a cross-sectional view schematically showing an example of the configuration of a plasma reactor; FIG. 1 is a plan view schematically showing an example of the configuration of a plasma reactor; FIG. 4 is a flow chart showing an example of the operation of a processing unit; FIG. 4 is a diagram schematically showing an example of a state of a processing unit in a liquid film forming process; It is a flowchart which shows an example of the operation|movement of a plasma processing process. It is a figure which shows roughly an example of the appearance of the processing unit in a plasma irradiation process. 4 is a graph showing an example of spatial temperature distribution around the plasma reactor; It is a figure which shows roughly an example of the appearance of the processing unit in a plasma irradiation process. 12 is an enlarged view showing an enlarged part of the processing unit of FIG. 11; FIG. It is an enlarged view which shows roughly an example of a part of appearance of a processing unit in a plasma irradiation process. It is a figure which shows roughly an example of a structure of the processing unit concerning 2nd Embodiment. FIG. 10 is an enlarged view schematically showing an example of a portion of the processing unit in the plasma irradiation process according to the second embodiment; It is a figure which shows roughly the modification of a structure of the processing unit concerning 2nd Embodiment. FIG. 11 is a diagram schematically showing an example of a configuration of a processing unit according to a third embodiment; FIG. FIG. 11 is an enlarged view schematically showing an example of a portion of a processing unit in a plasma irradiation step according to the third embodiment;

Embodiments will be described below with reference to the attached drawings. Note that the components described in this embodiment are merely examples, and the scope of the present disclosure is not intended to be limited to them. In the drawings, for ease of understanding, the dimensions or number of each part may be exaggerated or simplified as necessary.

Expressions indicating relative or absolute positional relationships (e.g., "in one direction", "along one direction", "parallel", "perpendicular", "center", "concentric", "coaxial", etc.) are used unless otherwise specified. Not only the positional relationship is strictly expressed, but also the relatively displaced state in terms of angle or distance within the range of tolerance or equivalent function. Expressions indicating equality (e.g., "same", "equal", "homogeneous", etc.), unless otherwise specified, not only express quantitatively strictly equality, but also tolerances or equivalent functions can be obtained It shall also represent the state in which there is a difference. Expressions indicating shapes (e.g., "square shape" or "cylindrical shape"), unless otherwise specified, not only represent the shape strictly geometrically, but also to the extent that the same effect can be obtained, such as Shapes having unevenness or chamfering are also represented. The terms "comprise", "comprise", "comprise", "include" or "have" an element are not exclusive expressions that exclude the presence of other elements. The phrase "at least one of A, B and C" includes only A, only B, only C, any two of A, B and C, and all of A, B and C.

<First embodiment>
<Overall Configuration of Substrate Processing Apparatus>
FIG. 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus 100. FIG. The substrate processing apparatus 100 is a single wafer processing apparatus that processes substrates W to be processed one by one.

The substrate W is, for example, a semiconductor substrate and has a disk shape. In addition to the semiconductor substrate, the substrate W includes a photomask glass substrate, a liquid crystal display glass substrate, a plasma display glass substrate, a FED (Field Emission Display) substrate, an optical disk substrate, a magnetic disk substrate, and a magneto-optical substrate. Various substrates such as disk substrates can be applied. Also, the shape of the substrate is not limited to a disk shape, and various shapes such as a rectangular plate shape can be adopted.

The substrate processing apparatus 100 includes a load port 101 , an indexer robot 110 , a main transfer robot 120 , a plurality of processing units 130 and a control section 90 .

A plurality of load ports 101 are arranged side by side along one horizontal direction. Each load port 101 is an interface section for loading/unloading the substrate W into/from the substrate processing apparatus 100 . A carrier C, which is a substrate container for accommodating substrates W, is loaded into each load port 101 from the outside. Each load port 101 holds the loaded carrier C. As shown in FIG.

The indexer robot 110 is a transport robot that transports the substrate W between the carrier C held by each load port 101 and the main transport robot 120 . The indexer robot 110 can move along the direction in which the load ports 101 are arranged, and can stop at a position facing each carrier C. As shown in FIG. The indexer robot 110 can perform an operation of picking up the substrates W from each carrier C and an operation of transferring the substrates W to each carrier C. As shown in FIG.

The main transport robot 120 is a transport robot that transports substrates W between the indexer robot 110 and each processing unit 130 . The main transport robot 120 can perform an operation of receiving the substrate W from the indexer robot 110 and an operation of transferring the substrate W to the indexer robot 110 . Further, the main transport robot 120 can perform an operation of loading the substrate W into each processing unit 130 and an operation of unloading the substrate W from each processing unit 130 .

For example, 12 processing units 130 are arranged in the substrate processing apparatus 100 . Specifically, four towers each including three vertically stacked processing units 130 are provided so as to surround the main transfer robot 120 . In FIG. 1, one of the three-tiered processing units 130 is schematically shown. Note that the number of processing units 130 in the substrate processing apparatus 100 is not limited to 12, and may be changed as appropriate.

The main transport robot 120 is provided so as to be surrounded by four towers. The main transport robot 120 loads unprocessed substrates W received from the indexer robot 110 into the processing units 130 . Each processing unit 130 processes a substrate W. FIG. Further, the main transport robot 120 unloads the processed substrate W from each processing unit 130 and passes it to the indexer robot 110 .

The control unit 90 controls the operation of each component of the substrate processing apparatus 100 . FIG. 2 is a functional block diagram schematically showing an example of the internal configuration of the control section 90. As shown in FIG. The control unit 90 is an electronic circuit and has, for example, a data processing unit 91 and a storage unit 92 . In the specific example of FIG. 2, the data processing section 91 and the storage section 92 are interconnected via a bus 93 . The data processing unit 91 may be an arithmetic processing device such as a CPU (Central Processor Unit). The storage unit 92 may have a non-temporary storage unit (eg, ROM (Read Only Memory) or hard disk) 921 and a temporary storage unit (eg, RAM (Random Access Memory)) 922 . The non-temporary storage unit 921 may store, for example, a program that defines processing to be executed by the control unit 90 . By the data processing unit 91 executing this program, the control unit 90 can execute the processing specified in the program. Of course, part or all of the processing executed by the control unit 90 may be executed by hardware.

<Processing unit>
FIG. 3 is a diagram schematically showing an example of the configuration of the processing unit 130. As shown in FIG. It is not necessary for all the processing units 130 belonging to the substrate processing apparatus 100 to have the configuration shown in FIG. 3, and at least one processing unit 130 may have the configuration.

The processing unit 130 illustrated in FIG. 3 is an apparatus that performs processing on the substrate W using plasma. The substrate W is, for example, a semiconductor substrate and has a disk shape. Although the size of the substrate W is not particularly limited, its diameter R1 is, for example, about 300 mm. Although the treatment using plasma need not be particularly limited, a more specific example includes organic matter removal treatment. The organic substance removing process is a process for removing organic substances on the main surface of the substrate W, and a resist can be applied as the organic substances. When the organic matter is a resist, the organic matter removing treatment can also be said to be a resist removing treatment.

The processing unit 130 includes a plasma reactor 1, a substrate holder 3, and a guard 7. In the example of FIG. 3, processing unit 130 also includes chamber 80 . The chamber 80 forms a processing chamber for processing the substrate W, and accommodates various components described later.

The substrate holding part 3 is provided inside the chamber 80 and holds the substrate W in a horizontal posture. The horizontal posture referred to here is a posture in which the thickness direction of the substrate W is along the vertical direction. In the example of FIG. 3, the substrate holder 3 includes a spin base 31 and multiple chuck pins 32 . The spin base 31 has a disk shape and is provided below the substrate W in the vertical direction. The spin base 31 is provided in such a posture that its thickness direction is along the vertical direction. A plurality of chuck pins 32 are erected on the upper surface of the spin base 31 and grip the peripheral edge of the substrate W. As shown in FIG. It should be noted that the substrate holding part 3 does not necessarily have to have the chuck pins 32 . For example, the substrate holding part 3 may suck the substrate W by sucking the lower surface of the substrate W. As shown in FIG.

In the example of FIG. 3, the substrate holder 3 further includes a rotation mechanism 33, which rotates the substrate W around the rotation axis Q1. The rotation axis Q1 is an axis that passes through the center of the substrate W and extends in the vertical direction. Rotation mechanism 33 includes, for example, shaft 34 and motor 35 . The upper end of shaft 34 is connected to the lower surface of spin base 31 . The motor 35 rotates the shaft 34 around the rotation axis Q1 to rotate the spin base 31 . Thereby, the substrate W held by the plurality of chuck pins 32 rotates around the rotation axis Q1. Such a substrate holding part 3 can also be called a spin chuck. Hereinafter, the radial direction about the rotation axis Q1 is simply referred to as the radial direction.

In the example of FIG. 3, the processing unit 130 also includes the nozzle 4. The nozzle 4 is provided in the chamber 80 and used to supply the substrate W with the processing liquid. The nozzle 4 is connected to a processing liquid supply source 44 via a supply pipe 41 . The processing liquid supply source 44 includes, for example, a tank (not shown) that stores the processing liquid. The processing liquid includes, for example, at least one chemical liquid of sulfuric acid, sulfate, peroxosulfate, and peroxosulfate. A valve 42 is interposed in the supply pipe 41 . By opening the valve 42 , the processing liquid from the processing liquid supply source 44 is supplied to the nozzle 4 through the supply pipe 41 and discharged from the discharge port 4 a of the nozzle 4 .

In the example of FIG. 3, the nozzle 4 is movably provided by a nozzle moving mechanism 45. A nozzle moving mechanism 45 moves the nozzle 4 between the nozzle processing position and the nozzle standby position. The nozzle processing position is a position where the nozzle 4 discharges the processing liquid toward the main surface (for example, the upper surface) of the substrate W. As shown in FIG. The nozzle processing position is, for example, a position vertically above the substrate W and facing the central portion of the substrate W in the vertical direction. The nozzle standby position is, for example, a position radially outside the peripheral edge of the substrate W. As shown in FIG. FIG. 3 shows the nozzles 4 stopped at the nozzle standby position.

The nozzle moving mechanism 45 has, for example, a ball screw mechanism or an arm turning mechanism. The arm turning mechanism includes an arm, a support column, and a motor (none of which are shown). The arm has a horizontally extending rod-like shape, the tip of the arm is connected to the nozzle 4, and the base end of the arm is connected to the support column. The support column extends vertically and is rotatable around its central axis. When the motor rotates the support column, the arm turns and the nozzle 4 moves in the circumferential direction around the central axis. A support column is provided so that the nozzle processing position and the nozzle standby position are positioned on the moving path of the nozzle 4 .

When the valve 42 is opened with the nozzle 4 positioned at the nozzle processing position, the processing liquid is discharged from the nozzle 4 toward the upper surface of the substrate W (see also FIG. 7). When the substrate holding unit 3 rotates the substrate W, the processing liquid spreads over the upper surface of the substrate W due to centrifugal force and scatters outward from the peripheral edge of the substrate W. FIG. As a result, a liquid film F1 of the processing liquid is formed on the upper surface of the substrate W. As shown in FIG.

The nozzle 4 may sequentially eject multiple types of treatment liquids. In this case, the nozzle 4 may be connected to another processing liquid supply source (not shown) through a supply pipe (not shown) branched from the supply pipe 41 . Alternatively, multiple nozzles 4 may be provided and each nozzle 4 may be connected to multiple processing liquid supplies. The nozzle moving mechanism 45 may move the plurality of nozzles 4 together or individually. As the treatment liquid, for example, pure water and rinsing liquid such as isopropyl alcohol can be applied.

The guard 7 is provided inside the chamber 80 and has a tubular shape for surrounding the substrate holding part 3 and the substrate W held by the substrate holding part 3 . The guard 7 is provided to catch the processing liquid scattered from the periphery of the substrate W. As shown in FIG.

In the example of FIG. 3, the guard 7 includes a cylindrical portion 71 surrounding the substrate holding portion 3, an inclined portion 72 and an upper end portion 73. The inclined portion 72 is inclined so as to approach the rotation axis Q1 as it goes vertically upward. That is, the inner diameter and the outer diameter of the inclined portion 72 decrease vertically upward. The upper end of the cylindrical portion 71 is continuous with the lower end of the inclined portion 72, and the cylindrical portion 71 extends along the vertical direction. In the example of FIG. 3 , the upper end of the inclined portion 72 is continuous with the outer peripheral edge of the upper end portion 73 . The upper end portion 73 has a ring-shaped plate shape extending horizontally. In the example of FIG. 3, the upper and lower surfaces of upper end 73 are parallel to the horizontal plane. An inner peripheral edge of the upper end portion 73 forms an upper opening of the guard 7 .

In the example of FIG. 3, the processing unit 130 includes multiple guards 7 . A plurality of guards 7 are provided concentrically and all surround the substrate holder 3 . In the example of FIG. 3, two guards 7 are provided. Hereinafter, the outermost guard 7 is called guard 7A, and the innermost guard 7 is also called guard 7B.

The guard 7 can be moved up and down by a guard elevating mechanism 75 (corresponding to a second elevating mechanism). A guard elevating mechanism 75 elevates the guard 7 between the upper position and the guard standby position. The upper position is the position where the guard 7 receives the processing liquid. The guard standby position is, for example, a position where the upper surface of the upper end portion 73 of the guard 7 is vertically below the upper surface of the spin base 31 . The example of FIG. 3 shows the guard 7 stopped at the guard standby position. The guard lifting mechanism 75 may include, for example, a ball screw mechanism and a motor that applies a driving force to the ball screw mechanism, or may include an air cylinder. When a plurality of guards 7 are provided, the guard lifting mechanism 75 lifts and lowers the guards 7 individually.

When the guard elevating mechanism 75 raises the guards 7A and 7B to the upper position, the processing liquid scattered from the peripheral edge of the substrate W is received by the inner peripheral surface of the guard 7B and flows down along the inner peripheral surface of the guard 7B. do. A cup 76 receives the processing liquid flowing down along the inner peripheral surface of the guard 7B. The processing liquid is recovered through a recovery pipe 77 connected to the cup 76, for example, in a tank of the same type of processing liquid supply source.

In a state in which the guard elevating mechanism 75 lowers the guard 7B to the guard standby position and raises the guard 7A to the upper position, the processing liquid scattered from the peripheral edge of the substrate W is received by the inner peripheral surface of the guard 7A. It flows down along the inner peripheral surface. A cup (not shown) catches the processing liquid flowing down along the inner peripheral surface of the guard 7A. The processing liquid is recovered, for example, in a tank of the same type of processing liquid supply source through a recovery pipe (not shown) connected to the cup.

As described above, by providing a plurality of guards 7, it is possible to collect the processing liquid according to its type.

The plasma reactor 1 is a plasma generator that generates plasma, and is provided in the chamber 80 at a position facing the upper surface of the substrate W held by the substrate holding part 3 in the vertical direction. The plasma reactor 1 is connected to a power supply 16 for plasma, receives power from the power supply 16, and converts surrounding gas into plasma. Here, as an example, the plasma reactor 1 generates plasma under atmospheric pressure. The atmospheric pressure here is, for example, 80% or more of the standard pressure and 120% or less of the standard pressure.

The plasma reactor 1 is a flat plasma reactor having a flat shape. The plasma reactor 1 extends radially outward from the periphery of the substrate W in plan view. The outer periphery of the plasma reactor 1 has, for example, a circular shape in plan view, and its outer diameter R2 is larger than the diameter R1 of the substrate W. As shown in FIG. In the example of FIG. 3, the outer diameter R2 of the plasma reactor 1 is larger than the inner diameter (corresponding to the upper opening diameter) R3 of the upper end portion 73 of the guard 7 . According to this structure, the portion of the plasma reactor 1 outside the peripheral edge of the substrate W faces the upper end portion 73 of the guard 7 in the vertical direction. An example of a specific internal configuration of the plasma reactor 1 will be detailed later.

The plasma reactor 1 is provided to be vertically movable by a plasma lifting mechanism 15 (corresponding to a first lifting mechanism). The plasma elevating mechanism 15 elevates the plasma reactor 1 between the plasma processing position and the plasma standby position. The plasma processing position is a position where the substrate W is processed using plasma from the plasma reactor 1 . At the plasma processing position, the distance between the plasma reactor 1 and the upper surface of the substrate W is, for example, about several mm (specifically, about 2 mm). The plasma standby position is a position when the substrate W is not processed using plasma, and is a position vertically above the plasma processing position. FIG. 3 shows the plasma reactor 1 stopped at the plasma standby position. The plasma elevating mechanism 15 may include, for example, a ball screw mechanism and a motor for driving the ball screw mechanism, or may include an air cylinder.

The plasma reactor 1 can move from the plasma standby position to the plasma processing position with the nozzle 4 retracted to the nozzle standby position and all the guards 7 being lowered to, for example, the guard standby position. The plasma reactor 1 moves to the plasma processing position, for example, with the liquid film F1 of the processing liquid formed on the upper surface of the substrate W (see also FIG. 9).

The plasma reactor 1 irradiates the upper surface of the substrate W with plasma in a processing state in which the guard 7 is positioned at the lower position (for example, the guard standby position) and the plasma reactor 1 is positioned at the plasma processing position. When the plasma reactor 1 generates plasma, various active species are generated. For example, plasmatization of air can generate various active species such as oxygen radicals, hydroxyl radicals, and ozone gas. These active species act on the upper surface of the substrate W. As shown in FIG. As a specific example, the active species act on the liquid film of the processing liquid (here, sulfuric acid) on the upper surface of the substrate W. As shown in FIG. This enhances the processing performance of the processing liquid. Specifically, the reaction between active species and sulfuric acid produces caro's acid with high processing performance (here, oxidizing power). Caro's acid is also called peroxomonosulfate. The Caro's acid acts on the resist on the substrate W, so that the resist can be removed by oxidation.

By the way, due to the generation of plasma, the temperature around the plasma reactor 1 increases. For example, the temperature is several hundred degrees Celsius, and as a more specific example, it ranges from about 200 degrees Celsius to about 350 degrees Celsius. As a result, the processing liquid on the upper surface of the substrate W evaporates easily, and the atmosphere immediately above the substrate W contains a large amount of volatile components of the processing liquid. If such an atmosphere of the processing liquid diffuses into the chamber 80, the volatile components of the processing liquid may adhere to the members inside the chamber 80, causing problems. Therefore, in order to suppress such diffusion of the processing liquid atmosphere, the processing unit 130 is provided with an air supply section 81 and an exhaust section 82 .

In the example of FIG. 3, the air supply section 81 is provided on the ceiling of the chamber 80. The gas supply unit 81 sucks gas (for example, air) from the outside of the chamber 80 , removes impurities from the gas with a filter, and supplies the removed gas to the inside of the chamber 80 . A so-called down flow is thereby formed in the chamber 80 . The air supply unit 81 is, for example, a fan filter unit.

In the example of FIG. 3, the exhaust section 82 includes a cylindrical member 83 and an exhaust pipe 84. A tubular member 83 is provided within the chamber 80 . The tubular member 83 has a tubular shape and surrounds the guard 7 from the outer peripheral side of the outermost guard 7 . A cylindrical member 83 is provided on the floor of the chamber 80 . An upstream end of an exhaust pipe 84 is connected to a lower portion of the cylindrical member 83, and a suction mechanism (not shown) is connected to a downstream end of the exhaust pipe 84. As shown in FIG. The processing liquid atmosphere above the substrate W flows into the upstream end of the exhaust pipe 84 through the inside of the guard 7 and is discharged to the outside of the chamber 80 through the exhaust pipe 84 . In FIG. 3, the flow of this airflow is schematically indicated by dashed arrows.

Next, a specific example of the configuration of the plasma reactor 1 will be described. FIG. 4 is a cross-sectional view schematically showing an example of the configuration of the plasma reactor 1, and FIG. 5 is a plan view schematically showing an example of the configuration of the plasma reactor 1. As shown in FIG. In the example of FIGS. 4 and 5, plasma reactor 1 includes electrode assembly 10 and holding member 20 .

In the examples of FIGS. 4 and 5, the electrode assembly 10 includes a first electrode section 11 and a second electrode section 12 . The first electrode portion 11 has a comb shape including a plurality of first linear electrodes 111 and first collective electrodes 112 . The second electrode portion 12 also has a comb shape including a plurality of second linear electrodes 121 and second collective electrodes 122 .

The first linear electrode 111 and the second linear electrode 121 are made of a conductive material such as a metal material (eg, tungsten) and have a rod-like shape (eg, cylindrical shape) extending along the horizontal longitudinal direction. In the example of FIG. 5, in plan view, the first linear electrodes 111 and the second linear electrodes 121 are provided parallel to each other and arranged alternately in the arrangement direction perpendicular to and horizontal to the longitudinal direction. The first collective electrode 112 connects ends (base ends) on one side in the longitudinal direction of the plurality of first linear electrodes 111 . The second collective electrode 122 connects the ends (base ends) on the other side in the longitudinal direction of the plurality of second linear electrodes 121 . In the example of FIG. 5, the first collective electrode 112 and the second collective electrode 122 have arcuate plate shapes with substantially the same diameter that curve in opposite directions. The first collective electrode 112 and the second collective electrode 122 are made of a conductive material such as a metal material (for example, aluminum).

In the examples of FIGS. 4 and 5, each first linear electrode 111 is covered with the first dielectric 13 and each second linear electrode 121 is covered with the second dielectric . The first dielectric 13 and the second dielectric 14 are made of dielectric materials such as quartz and ceramics. Each of the first dielectric 13 and the second dielectric 14 has, for example, a tubular shape extending along the longitudinal direction. A first linear electrode 111 is inserted into the first dielectric 13 along the longitudinal direction, and a second linear electrode 121 is inserted into the second dielectric 14 along the longitudinal direction. Thereby, the first linear electrode 111 and the second linear electrode 121 can be suppressed from being sputtered by the plasma. As a result, contamination of the substrate W caused by sputtered particles can be suppressed.

In the examples of FIGS. 4 and 5, the plasma reactor 1 is provided with a partition member 17 . The partition member 17 is made of dielectric material such as quartz and ceramics. The partition member 17 has, for example, a disc shape, and is provided in a posture in which the thickness direction thereof extends along the vertical direction. First linear electrode 111 and first dielectric 13 are provided on the upper surface of partition member 17 , and second linear electrode 121 and second dielectric 14 are provided on the lower surface of partition member 17 .

The holding member 20 is made of an insulating material such as fluorine-based resin, and holds the first electrode portion 11, the second electrode portion 12, the first dielectric 13, the second dielectric 14 and the partition member 17 integrally. For example, the holding member 20 has a ring shape centered on the rotation axis Q1 in plan view. In the example of FIG. 4, the holding member 20 includes an upper member 21 and a lower member 22 that are connected together. The upper member 21 and the lower member 22 sandwich at least the first collective electrode 112 and the second collective electrode 122 from opposite sides in the vertical direction. The lower member 22 contacts at least the lower surface of each of the first collective electrode 112 and the second collective electrode 122 to support them.

In such a plasma reactor 1 , the holding member 20 protrudes vertically upward and downward from the electrode assembly 10 . That is, the ring-shaped upper member 21 protrudes vertically above the electrode assembly 10 , and the ring-shaped lower member 22 protrudes below the electrode assembly 10 . The inner peripheral surface 23 of the ring-shaped lower member 22 is, for example, a cylindrical surface centered on the rotation axis Q1. In the example of FIG. 4, the inner peripheral surface 23 of the lower member 22 is located radially outside the peripheral edge of the substrate W. In the example of FIG. That is, the inner diameter R21 of the lower member 22 is larger than the diameter R1 of the substrate W. As shown in FIG. In the example of FIG. 4, the lower surface 24 of the lower member 22 is parallel to the horizontal plane.

The first electrode portion 11 and the second electrode portion 12 are electrically connected to a power source 16 for plasma. The power supply 16 has, for example, a switching power supply circuit (not shown), and outputs voltage for plasma between the first electrode portion 11 and the second electrode portion 12 . As a specific example, the power supply 16 outputs a high frequency voltage as a voltage for plasma. Thereby, an electric field for plasma is generated between the first linear electrode 111 and the second linear electrode 121 . According to the electric field, the gas around the first linear electrode 111 and the second linear electrode 121 becomes plasma (so-called dielectric barrier discharge).

In the example of FIG. 4, the base end and the tip of the first linear electrode 111 are located radially outside the peripheral edge of the substrate W, and the base end and the tip of the second linear electrode 121 are located radially outside the peripheral edge of the substrate W. are also located radially outward. All first linear electrodes 111 and all second linear electrodes 121 may be the same. According to this structure, the plasma reactor 1 can generate plasma in a two-dimensional range wider than the upper surface of the substrate W in plan view, and the active species can act on the upper surface of the substrate W more uniformly.

<Example of operation of substrate processing apparatus>
Next, an example of the operation of the processing unit 130 will be described. FIG. 6 is a flow chart showing an example of the operation of the processing unit 130. As shown in FIG. First, the substrate holding part 3 holds the substrate W (step S1: holding step). Specifically, the main transport robot 120 transfers the unprocessed substrate W to the substrate holding unit 3, and the substrate holding unit 3 holds the substrate W. FIG.

Next, the processing unit 130 forms a liquid film F1 of the processing liquid on the upper surface of the substrate W (step S2: liquid film forming step). FIG. 7 is a diagram schematically showing an example of the state of the processing unit 130 in the liquid film forming process. As illustrated in FIG. 7, the nozzle moving mechanism 45 moves the nozzle 4 to the nozzle processing position, and the guard lifting mechanism 75 lifts the guard 7 to the upper position. In the example of FIG. 7, both guard 7A and guard 7B are in the upper position. Then, the substrate holder 3 rotates the substrate W around the rotation axis Q1, and the valve 42 is opened. As a result, the processing liquid is supplied from the ejection port 4a of the nozzle 4 toward the upper surface of the substrate W during rotation. Here, sulfuric acid is supplied as the processing liquid. The processing liquid that has landed on the upper surface of the substrate W spreads over the upper surface of the substrate W. As shown in FIG. As a result, a liquid film F1 of the processing liquid is formed on the upper surface of the substrate W. As shown in FIG. In addition, the processing liquid scattered from the peripheral edge of the substrate W is received by the inner peripheral surface of the guard 7B.

When the liquid film F1 of the treatment liquid is formed, the valve 42 is closed to stop the supply of the treatment liquid, and the nozzle moving mechanism 45 moves the nozzle 4 to the nozzle standby position. Further, the substrate holding part 3 reduces the rotation speed of the substrate W. FIG. More specifically, the substrate holding unit 3 reduces the rotation speed to a speed (for example, 40 rpm or less) at which the liquid film F1 on the upper surface of the substrate W can be maintained (so-called paddle processing). The rotation speed of the substrate W may be zero. The film thickness of the liquid film F1 is, for example, 0.1 mm or more and 2.0 mm or less, preferably about 0.2 mm. In other words, the discharge amount of the treatment liquid and the rotation speed of the substrate W in the liquid film forming process are adjusted so that the film thickness of the liquid film F1 becomes the target value.

Next, the processing unit 130 performs plasma processing on the substrate W (step S3: plasma processing step). FIG. 8 is a flow chart showing a specific example of the plasma processing process, and FIG. 9 is a diagram schematically showing an example of the state of the processing unit 130 in the plasma processing process.

In the example of FIG. 8, first, the guard lifting mechanism 75 lowers the guard 7 to the lower position (step S31: guard moving step). The lower position referred to here is a position where the upper end 711 of the inner peripheral surface of the outermost guard 7A is vertically below the upper surface of the substrate W held by the substrate holding portion 3 . As a specific example of the lower position, a position where the upper end 711 of the guard 7A is vertically below the lower surface of the substrate W may be adopted, or the upper end 711 of the guard 7A is below the upper surface of the spin base 31. position may be employed, or a guard standby position may be employed. Here, the guard standby position is adopted as the lower position. That is, the guard elevating mechanism 75 lowers the guard 7A and the guard 7B to the guard standby position.

Next, the power supply 16 outputs voltage for plasma to the plasma reactor 1 (step S32: lighting step). Thereby, plasma is generated around the plasma reactor 1 . Note that the lighting process may be performed before the guard moving process.

Next, the plasma elevating mechanism 15 lowers the plasma reactor 1 from the plasma standby position to the plasma processing position (step S33: plasma movement step). When the plasma reactor 1 is positioned at the plasma processing position, the plasma reactor 1 can irradiate the substrate W with plasma (step S34: plasma irradiation step). In other words, the plasma processing position is a position close to the substrate W to the extent that the substrate W can be irradiated with plasma.

FIG. 9 shows the state of the processing unit 130 in the plasma irradiation process. In the example of FIG. 9, the plasma reactor 1 is located at the plasma processing position, irradiates the liquid film F1 on the upper surface of the substrate W with plasma, and supplies active species to the liquid film F1. As a result, the processing performance of the processing liquid is improved, and the processing liquid acts on the substrate W with high processing performance. More specifically, oxygen radicals react with sulfuric acid to produce Caro's acid, which removes the resist on the substrate W. FIG.

In this plasma irradiation process, the substrate holder 3 may rotate the substrate W at a low speed (for example, 40 rpm or less), or may stop the rotation of the substrate W. When the substrate W rotates, the active species act more uniformly on the substrate W, so that the uniformity of processing on the substrate W can be improved.

Then, when the resist on the substrate W is sufficiently removed, the plasma elevating mechanism 15 raises the plasma reactor 1 to the plasma standby position, and the power supply 16 stops outputting voltage (step S35).

Next, the processing unit 130 performs a rinsing process on the upper surface of the substrate W (step S4: rinsing process). Specifically, the processing unit 130 supplies the rinsing liquid from the nozzle 4 to the top surface of the substrate W during rotation, and replaces the processing liquid on the top surface of the substrate W with the rinsing liquid.

Next, the processing unit 130 performs a drying process on the substrate W (step S5: drying process). For example, the substrate holding unit 3 rotates the substrate W at a higher rotation speed than the plasma processing step, thereby drying the substrate W (so-called spin drying). Next, the main transport robot 120 unloads the processed substrate W from the processing unit 130 .

<Effect of Embodiment>
As described above, in the present embodiment, in the plasma processing step, the plasma reactor 1 is stopped at the plasma processing position while the upper end 711 of the guard 7 is stopped at the lower position below the lower surface of the substrate W. (See Figure 9). That is, the upper end of the guard 7A is at a lower position than when the guard 7 is positioned at the upper position. Therefore, even if the size of the plasma reactor 1 in plan view is increased, the plasma reactor 1 can be lowered to a plasma processing position closer to the substrate W without physically interfering with the guard 7 . That is, by lowering the guard 7A located below the plasma reactor 1 to a lower position, the plasma reactor 1 can also be lowered further.

Here, the temperature distribution of the plasma reactor 1 will be explained. When the plasma reactor 1 generates plasma, the temperature rises due to the plasma generation. FIG. 10 is a graph showing an example of spatial temperature distribution around the plasma reactor 1. In FIG. The horizontal axis indicates the radial distance from the center of the plasma reactor 1 (that is, the rotation axis Q1), and the vertical axis indicates the temperature at a position vertically below the plasma reactor 1 by 10 mm.

The example in FIG. 10 also shows a plasma generation region where plasma is generated. As can be understood from FIG. 10, in the region between the center of the plasma reactor 1 and an intermediate position about 130 mm away from the center in the radial direction, the temperature gradually decreases as the distance from the center increases. is relatively small. On the other hand, in the region between the intermediate position and the edge position of the plasma generation region (position at a distance of about 150 mm), the temperature drops sharply as the distance from the center increases. That is, the temperature at the peripheral edge of the plasma generation region is significantly lower than the temperature at the center of the plasma generation region.

Since the plasma reactor 1 is close to the substrate W in the plasma irradiation process, the temperature distribution of the upper surface of the substrate W is affected by the temperature distribution of the plasma reactor 1 . Therefore, when the size of the plasma reactor 1 in a plan view is about the same as that of the substrate W, even if the entire upper surface of the substrate W can be irradiated with plasma, the temperature of the periphery of the substrate W is higher than that of the central portion. becomes smaller. Therefore, a difference occurs in the degree of processing between the central portion and the peripheral portion of the substrate W. FIG.

In contrast, in the present embodiment, the guard 7 is positioned vertically below the plasma reactor 1 in the plasma irradiation step, so the outer diameter R2 and the inner diameter R21 of the plasma reactor 1 are irrelevant to the inner diameter R3 of the guard 7. can be designed to Therefore, the size of the plasma reactor 1 can be increased to widen the plasma generation area. Specifically, the size of the plasma reactor 1 can be designed such that a region with a more uniform temperature distribution faces the entire upper surface of the substrate W. FIG. According to this structure, the temperature distribution on the upper surface of the substrate W can be made more uniform, and the uniformity of the processing of the substrate W can be improved.

<Gap Between Plasma Reactor 1 and Guard 7>
In the example of FIG. 9, since the guard 7 is stopped at the guard standby position in the plasma processing step, there is a relatively wide gap between the lower member 22 of the plasma reactor 1 and the upper end portion 73 of the guard 7A. is occurring.

Now, when the plasma reactor 1 generates plasma, the ambient temperature rises up to several hundred degrees Celsius, as described above, so the processing liquid on the substrate W is likely to evaporate. Therefore, the atmosphere between the substrate W and the plasma reactor 1 contains many volatile components of the processing liquid.

In the present embodiment, an air supply unit 81 and an exhaust unit 82 (see FIG. 3) are provided. can flow into In the example of FIG. 9, a part of the possible flow of the processing liquid atmosphere is schematically indicated by dashed arrows. The possibility of the processing liquid atmosphere flowing out of the guard 7 increases as the rotation speed of the substrate W in the plasma processing step increases.

Therefore, in order to suppress such an outflow, the guard lifting mechanism 75 may position the guard 7A at a guard intermediate position higher than the guard standby position in the plasma processing process. FIG. 11 is a diagram schematically showing an example of the state of the processing unit 130 in the plasma processing step, and FIG. 12 shows a portion of the processing unit 130 (specifically, the area surrounded by the dashed line) in FIG. It is an enlarged view which expands and shows.

In the examples of FIGS. 11 and 12, the plasma reactor 1 stops at the plasma processing position, and the guard 7A stops at the guard intermediate position. The guard intermediate position is a position where the distance D1 between the plasma reactor 1 positioned at the plasma processing position and the outermost guard 7A is narrower than the distance D2 between the guard 7A and the substrate holder 3. FIG. In the example of FIG. 12, the distance D1 is the distance between the lower surface 24 of the lower member 22 of the plasma reactor 1 and the upper surface of the upper end portion 73 of the guard 7A, and the distance D2 is the inner peripheral edge of the upper end portion 73 of the guard 7A. and the side of the spin base 31. Even when the guard 7A stops at the guard intermediate position, the upper end 711 of the inner peripheral surface of the guard 7A is positioned below the upper surface of the substrate W, so the guard intermediate position is also included in the concept of the lower position.

If the guard 7A stops at the guard intermediate position, the space D1 becomes narrower than the space D2, so the processing liquid atmosphere flows more easily through the gap between the guard 7A and the substrate holder 3 than between the plasma reactor 1 and the guard 7A. . According to this, it is possible to suppress the processing liquid atmosphere from flowing out of the guard 7 and diffusing into the chamber 80 .

Further, when the substrate holding unit 3 rotates the substrate W in the plasma processing step, the processing liquid may splash from the periphery of the substrate W. If the interval D1 is equal to or smaller than the interval D2, the processing liquid also hardly passes through the gap between the plasma reactor 1 and the guard 7 and easily flows down through the gap between the guard 7 and the substrate holder 3 . Therefore, it is possible to prevent the processing liquid from flowing out of the guard 7 .

Further, when the interval D1 becomes narrower, the negative pressure inside the guard 7 increases due to the exhaust by the exhaust section 82 . Therefore, the flow velocity of the airflow passing radially inward through the gap between the plasma reactor 1 and the guard 7 from the outside of the guard 7 increases. This airflow makes it difficult for the processing liquid atmosphere and the processing liquid to pass through the gap between the plasma reactor 1 and the guard 7 in the radial direction, further suppressing the flow of the processing liquid atmosphere and the processing liquid to the outside of the guard 7 .

<Outer portion of plasma reactor>
In the above example, the lower member 22 (corresponding to the outer portion) positioned outside the peripheral edge of the substrate W in the plasma reactor 1 has a ring shape and protrudes vertically below the electrode assembly 10 . . The lower surface 24 of the lower member 22 is located vertically below the upper surface of the substrate W in the plasma processing step (see FIGS. 9, 11 and 12). That is, the lower surface 24 of the lower member 22 is positioned vertically below the lower surface of the substrate W in the processing state in which the plasma reactor 1 is positioned at the plasma processing position. In this case, the inner peripheral surface 23 of the lower member 22 can surround the space above the substrate W. FIG. Therefore, the lower member 22 can substantially function as part of the guard.

Specifically, when the processing liquid atmosphere between the plasma reactor 1 and the substrate W flows radially outward, it collides with the inner peripheral surface 23 of the lower member 22 and vertically downward along the inner peripheral surface 23 . flow. Moreover, even if the processing liquid scatters radially outward from the peripheral edge of the substrate W, the processing liquid collides with the inner peripheral surface 23 of the lower member 22 and also flows vertically downward along the inner peripheral surface 23 . In the example of FIG. 12, the atmosphere of the processing liquid and the flow of the processing liquid are schematically indicated by two-dot chain arrows.

According to this structure, it is difficult for the processing liquid atmosphere and the processing liquid to pass through the gap between the plasma reactor 1 and the guard 7 to the outside in the radial direction. .

As exemplified in FIG. 12 , the lower end peripheral edge 231 of the inner peripheral surface 23 of the lower member 22 may be located radially inward from the inner peripheral edge of the upper end portion 73 of the guard 7 . In other words, the inner diameter R21 of the lower member 22 is smaller than the inner diameter R3 of the guard 7 . According to this structure, the processing liquid atmosphere and the processing liquid flowing vertically downward along the inner peripheral surface 23 of the lower member 22 hardly collide with the upper surface of the guard 7, and the gap between the guard 7 and the substrate holding section 3 is maintained. can pass through. Therefore, outflow of the processing liquid atmosphere and the processing liquid to the outside of the guard 7 can be further suppressed.

Further, as illustrated in FIG. 12 , the lower end peripheral edge 231 of the inner peripheral surface 23 of the lower member 22 may be located radially outside the peripheral edge of the substrate holding part 3 (that is, the side surface of the spin base 31). . In other words, the inner diameter R21 of the lower member 22 is larger than the diameter R4 of the spin base 31. As shown in FIG. According to this structure, the processing liquid atmosphere and the processing liquid flowing vertically downward along the inner peripheral surface 23 of the lower member 22 are less likely to collide with the upper surface of the spin base 31 .

Since the spin base 31 rotates around the rotation axis Q1, if the processing liquid atmosphere and the processing liquid collide with the upper surface of the spin base 31, they can receive centrifugal force and flow radially outward again. This increases the possibility that the processing liquid atmosphere and the processing liquid flow out of the guard.

On the other hand, if the inner diameter R21 of the lower member 22 is larger than the diameter R4 of the spin base 31, the amount of the processing liquid atmosphere and the processing liquid colliding with the spin base 31 can be reduced. Outflow to the outside of the guard 7 can be further suppressed.

Moreover, the lower member 22 that supports the electrode assembly 10 from below can function as a guard. Therefore, the manufacturing cost of the plasma reactor 1 can be reduced compared to the case where the plasma reactor 1 is separately provided with a member functioning as a guard.

<Guard 7A and Guard 7B>
In the example of FIGS. 11 and 12, the guard elevating mechanism 75 raises not only the outermost guard 7A but also the other guards 7B to a position higher than the guard standby position in the plasma processing process. With this configuration, the gap between the guards 7A and 7B is narrowed, so that the possibility of the processing liquid flowing into the space between the guards 7A and 7B can be reduced, and more processing liquid can flow into the cup 76. can flow down. Therefore, more processing liquid can be recovered appropriately.

<Moving timing of plasma reactor and guard>
In the example of FIG. 8, the plasma transfer step (step S33) is performed after the guard transfer step (step S31). That is, the plasma elevating mechanism 15 starts lowering the plasma reactor 1 after the guard 7 stops at the lower position. According to this, it is possible to more reliably avoid collision between the plasma reactor 1 and the guard 7 at a high speed.

On the other hand, the plasma transfer process may be performed in parallel with the guard transfer process. In short, the descent speed and descent timing of the plasma reactor 1 and the guard 7 should be adjusted so that the plasma reactor 1 does not collide with the guard 7 at a high speed. For example, the plasma elevating mechanism 15 may lower the plasma reactor 1 so that the plasma reactor 1 reaches the plasma processing position after the guard 7 reaches the lower position.

When the plasma transfer process and the guard transfer process are performed in parallel, the processing throughput can be improved.

<Guard middle position>
In the above example, the plasma reactor 1 and the outermost guard 7A are separated from each other in the vertical direction in the plasma processing step (see FIG. 12, for example). However, this is not necessarily the case, and the plasma reactor 1 and guard 7A may be in contact with each other in the vertical direction. In other words, a position where the outermost guard 7A contacts the plasma reactor 1 in the vertical direction may be adopted as the guard intermediate position.

FIG. 13 is an enlarged view schematically showing an example of the state of the processing unit 130 in the plasma processing process. In the example of FIG. 13, the lower surface 24 of the lower member 22 of the plasma reactor 1 is in contact with the upper surface of the upper end portion 73 of the outermost guard 7A.

According to this, the gap between the lower member 22 of the plasma reactor 1 and the upper end portion 73 of the guard 7A can be further reduced, so that the outflow of the processing liquid atmosphere and the processing liquid to the outside of the guard 7 can be further suppressed. can.

<Second Embodiment>
FIG. 14 is a diagram schematically showing an example of the configuration of the processing unit 130A according to the second embodiment, and FIG. 15 is an enlarged view showing an example of the state of the processing unit 130A in the plasma processing step. is. The configuration of the processing unit 130A according to the second embodiment is the same as that of the processing unit 130 according to the first embodiment, except for the presence or absence of the elastic seal member 5. FIG.

In the examples of FIGS. 14 and 15, the seal member 5 is provided on the outermost guard 7A. That is, the guard 7A includes a cylinder portion 71, an inclined portion 72, an upper end portion 73, and a seal member 5. As shown in FIG. The seal member 5 is made of an elastic member, for example, an elastic resin such as silicone or rubber. The seal member 5 is attached to the upper surface of the upper end portion 73 of the guard 7A and faces the plasma reactor 1 in the vertical direction. The seal member 5 is in close contact with the lower surface 24 of the lower member 22 of the plasma reactor 1 in the plasma processing step as described later. Thereby, the adhesion between the plasma reactor 1 and the guard 7A can be improved.

The seal member 5 has a ring shape centered on the rotation axis Q1, and its lower end is attached to the upper surface of the upper end portion 73. In the example of FIG. 15, the sealing member 5 has a bent shape. Specifically, the seal member 5 includes an upper ring portion 51 and a lower ring portion 52 . The upper ring portion 51 has an inclined ring shape in which the inner diameter and the outer diameter decrease from the vertically upward direction to the vertically downward direction. The lower ring portion 52 has an inclined ring shape in which the inner diameter and the outer diameter increase from the vertically upward direction to the vertically downward direction. Such a sealing member 5 can be easily elastically deformed so that the distance between the upper end of the upper ring portion 51 and the lower end of the lower ring portion 52 is narrowed.

An example of the operation of the processing unit 130A is the same as in the first embodiment. However, as exemplified in FIG. 15, in the plasma processing step, the guard elevating mechanism 75 moves the guard 7A to the guard intermediate position where the lower surface 24 of the lower member 22 of the plasma reactor 1 contacts the upper end of the seal member 5 . Let At this time, the seal member 5 is pressed vertically downward by the plasma reactor 1 and is elastically deformed, and is in close contact with the plasma reactor 1 .

According to this, there is almost no gap between the plasma reactor 1 and the guard 7A. Therefore, it is possible to further suppress or prevent the processing liquid atmosphere and the processing liquid from flowing out of the guard 7 in the plasma processing step.

FIG. 16 is a diagram schematically showing a modification of the processing unit 130A. In the example of FIG. 16, the sealing member 5 is provided in the plasma reactor 1. In the example of FIG. In other words, plasma reactor 1 includes sealing member 5 . The seal member 5 is attached to the lower surface 24 of the lower member 22 of the plasma reactor 1 and vertically faces the upper end portion 73 of the guard 7A. An example of the specific shape of the seal member 5 is as described above.

Also in this modification, the plasma reactor 1 contacts the guard 7A in the vertical direction in the plasma processing step. Specifically, the lower end of the seal member 5 of the plasma reactor 1 contacts the upper surface of the upper end portion 73 of the guard 7A. At this time, the seal member 5 is pressed vertically downward by the plasma reactor 1 and is elastically deformed. That is, as the guard intermediate position, the position where the lower end of the seal member 5 located at the plasma processing position is in close contact with the upper surface of the guard 7A is adopted.

This also makes it possible to further suppress or prevent the processing liquid atmosphere and the processing liquid from flowing out of the guard 7 in the plasma processing step.

In the above example, the sealing member 5 is provided only on one of the plasma reactor 1 and the guard 7A, but may be provided on both. In this case, in the plasma processing step, the sealing member 5 of the plasma reactor 1 and the sealing member 5 of the guard 7A may be in close contact in the vertical direction.

<Third Embodiment>
FIG. 17 is a diagram schematically showing an example of the configuration of the processing unit 130B according to the third embodiment, and FIG. 18 is an enlarged view showing an example of the state of the processing unit 130B in the plasma processing step. is. The configuration of the processing unit 130B according to the third embodiment is the same as that of the processing unit 130 according to the first embodiment, except for the presence or absence of the labyrinth structure 55. FIG.

The labyrinth structure 55 is realized by the uneven shape of the plasma reactor 1 and the guard 7A (see FIG. 18). A specific example will be described below.

In the example of FIG. 18, the lower member 22 of the plasma reactor 1 protrudes vertically below the electrode assembly 10, and the lower member 22 forms a convex portion. Further, in the example of FIG. 18, a convex portion 74 and a convex portion 78 are provided on the upper surface of the upper end portion 73 of the guard 7A. The convex portion 74 protrudes vertically upward from the upper surface of the upper end portion 73 at a position radially inner than the lower member 22 . The convex portion 78 protrudes vertically upward from the upper surface of the upper end portion 73 at a position radially outside the lower member 22 . In other words, a concave portion (groove) 79 is formed on the upper surface of the upper end portion 73 of the guard 7A at a position facing the lower member 22 in the vertical direction. Concave portion 79 is formed by convex portion 74 and convex portion 78 . Each of the protrusions 74 and 78 has, for example, a ring shape centered on the rotation axis Q1. In this case, the recess 79 also has a ring shape around the rotation axis Q1.

As illustrated in FIG. 18, in a processing state in which the plasma reactor 1 is positioned at the plasma processing position and the guard 7A is positioned at the lower position, the lower member 22, which is the convex portion of the plasma reactor 1, is positioned in the concave portion of the guard 7A. 79 is loosely inserted. That is, the lower surface 24 of the lower member 22 is located vertically below both the upper ends of the projections 74 and the upper ends of the projections 78 . However, the bottom surface of the lower member 22 is separated from the bottom surface of the recess 79 . The lower member 22 of the plasma reactor 1 is located between the projections 74 and 78 in the radial direction and faces them with a gap therebetween.

The lower member 22 of the plasma reactor 1 and the projections 74 and 78 of the guard 7A form a labyrinth structure 55 having irregularities in the radial direction. According to this structure, the gap between the plasma reactor 1 and the guard 7A functions as a labyrinth seal. Therefore, in the plasma processing step, it is possible to prevent the processing liquid atmosphere and the processing liquid from flowing out through the gap between the plasma reactor 1 and the guard 7A.

Also, since a gap is formed between the plasma reactor 1 and the guard 7A, gas outside the guard 7 flows into the guard 7A through the gap and can be discharged to the outside through the exhaust section 82. Therefore, clean gas can flow into the guard 7A. Therefore, the atmosphere above the substrate W can be made cleaner.

As described above, the substrate processing apparatus 100 and the substrate processing method have been described in detail, but the above description is illustrative in all aspects, and the substrate processing apparatus 100 and the substrate processing method are limited thereto. isn't it. It is understood that numerous variations not illustrated can be envisioned without departing from the scope of this disclosure. Each configuration described in each of the above embodiments and modifications can be appropriately combined or omitted as long as they do not contradict each other.

For example, although the plasma elevating mechanism 15 elevates the plasma reactor 1, it is not necessarily limited to this. Since the plasma elevating mechanism 15 only needs to elevate the plasma reactor 1 relative to the substrate holding part 3, the substrate holding part 3 may be elevated and lowered. may Further, since the guard lifting mechanism 75 only needs to lift the guard 7 with respect to the substrate holding portion 3, the substrate holding portion 3 may be lifted or lowered, or the substrate holding portion 3 and the guard 7 may be lifted and lowered.

Also, the processing for the substrate W is not necessarily limited to the resist removal processing. For example, it can be applied to all treatments that can improve the treating ability of the treatment liquid by means of active species.

1 plasma reactor 22 outer part (lower member)
15 First lifting mechanism (plasma lifting mechanism)
3 substrate holder 33 rotation mechanism 7, 7A, 7B guard 75 second elevating mechanism (guard elevating mechanism)
S1 holding step S31 guard moving step S32 lighting step S33 plasma moving step

Claims (13)

1. a substrate holder that holds the substrate;
   a plurality of concentric guards having a cylindrical shape surrounding the substrate holding portion;
   a plasma reactor that is provided vertically above the substrate holding part and spreads outward from the peripheral edge of the substrate held by the substrate holding part in a plan view;
   a first elevating mechanism for elevating the plasma reactor relative to the substrate holder;
   a second elevating mechanism for relatively elevating the plurality of guards with respect to the substrate holding unit;
   Among the plurality of guards, the upper end of the inner peripheral surface of the outermost guard is positioned vertically below the upper surface of the substrate, and the plasma reactor is close to the substrate. The substrate processing apparatus, wherein the plasma reactor irradiates the substrate with plasma in the processing state located at the plasma processing position.
2. The substrate processing apparatus according to claim 1,
   The substrate processing apparatus, wherein in the processing state, the distance between the plasma reactor and the outermost guard is narrower than the distance between the outermost guard and the substrate holding part.
3. The substrate processing apparatus according to claim 2,
   The substrate processing apparatus, wherein in the processing state, the plasma reactor abuts the guard in a vertical direction.
4. The substrate processing apparatus according to claim 3,
   An elastic sealing member is provided on at least one of a lower surface of a portion of the plasma reactor outside the periphery of the substrate and an upper surface of the outermost peripheral guard, the sealing member being in close contact with the other. processing equipment.
5. The substrate processing apparatus according to claim 2,
   A substrate processing apparatus, wherein a lower surface of a portion of the plasma reactor outside a peripheral edge of the substrate forms, in the processing state, a labyrinth structure having irregularities in a radial direction together with an upper surface of the outermost guard.
6. The substrate processing apparatus according to any one of claims 1 to 5,
   an outer portion of the plasma reactor outside the peripheral edge of the substrate has a ring shape projecting downward;
   the inner diameter of the outer portion is greater than the diameter of the substrate;
   The substrate processing apparatus, wherein, in the processing state, the lower surface of the outer portion is located below the upper surface of the substrate held by the substrate holding part.
7. The substrate processing apparatus according to claim 6,
   The substrate processing apparatus, wherein the inner diameter of the outer portion of the plasma reactor is equal to or smaller than the upper opening diameter of the outermost guard.
8. The substrate processing apparatus according to claim 6 or 7,
   the substrate holding unit includes a spin base facing the substrate vertically below the substrate;
   The substrate processing apparatus, wherein the inner diameter of the outer portion is larger than the diameter of the spin base.
9. The substrate processing apparatus according to any one of claims 6 to 8,
   the plasma reactor includes an electrode assembly powered for the plasma;
   The substrate processing apparatus, wherein the outer portion supports the electrode assembly from below.
10. The substrate processing apparatus according to any one of claims 1 to 9,
    further comprising a nozzle for supplying a treatment liquid to the main surface of the substrate held by the substrate holding part;
    the substrate holding unit includes a rotation mechanism that rotates the substrate around a vertical rotation axis,
    In a state in which the second elevating mechanism moves at least the outermost guard upward relative to the substrate holder, the nozzle discharges the processing liquid, and the substrate holder rotates the substrate. let
    The substrate processing apparatus, wherein the upper position is a position where the upper end is vertically above the upper surface of the substrate.
11. a holding step in which the substrate holding portion holds the substrate;
    a lighting step of lighting a plasma reactor that is provided at a position facing the upper surface of the substrate held by the substrate holding portion and spreads outward from the substrate in a plan view;
    It has a cylindrical shape surrounding the substrate holding portion, and the upper end of the outermost guard among a plurality of guards provided concentrically is positioned at a lower position lower than the substrate held by the substrate holding portion. a moving step of positioning a guard relative to the substrate holder and moving the plasma reactor to a plasma processing position proximate to the top surface of the substrate;
    A substrate processing method comprising:
12. The substrate processing method according to claim 11,
    The moving step includes
    a guard moving step of relatively moving at least the outermost guard to the lower position with respect to the substrate holding portion;
    and a plasma moving step of relatively moving the plasma reactor to the plasma processing position with respect to the substrate holder after the guard moving step.
13. The substrate processing method according to claim 11,
    The moving step includes
    a guard moving step of relatively moving at least the outermost guard to the lower position with respect to the substrate holding portion;
    and a plasma moving step of relatively moving the plasma reactor to the plasma processing position with respect to the substrate holder in parallel with the guard moving step.

Images