TWI659493B - Substrate processing apparatus, substrate processing system and substrate processing method - Google Patents

Abstract

A substrate processing apparatus capable of improving the yield of a static elimination process is provided. The substrate processing apparatus 10 is a device that performs a process of reducing a charged amount of a charged substrate. The substrate processing apparatus 10 includes a substrate holding means 1, an ultraviolet irradiation means 2, and an electrostatic field forming means 8. The substrate holding means 1 is used to hold a substrate. The ultraviolet irradiation means 2 is arranged so as to face the substrate held by the substrate holding means with a space therebetween, and irradiates the substrate with ultraviolet rays. The electrostatic field forming means 8 forms an electric field in the space to keep electrons released from the substrate away from the substrate.

Description

   Substrate processing device, substrate processing system, and substrate processing method   

The invention relates to a substrate processing device, a substrate processing system and a substrate processing method.

In the conventional manufacturing steps of a semiconductor substrate (hereinafter simply referred to as a "substrate"), various processes are applied to a substrate having an insulating film such as an oxide film using a substrate processing apparatus. For example, a processing liquid is supplied to a substrate on which a pattern of a resist has been formed on the surface, thereby performing a process such as etching on the surface of the substrate. After the etching or the like is completed, a photoresist removal process is performed on the substrate.

For a substrate processed by a substrate processing apparatus, a drying process such as dry etching or plasma CVD (Chemical Vapor Deposition) is carried out before being carried into the substrate processing apparatus. ). In such a drying process, a charge is generated in a device to be charged, so the substrate is carried into a substrate processing apparatus in a charged state (so-called carry-on charging). Next, in a substrate processing apparatus, when a processing solution having a specific resistance, such as a SPM (sulfuric acid / hydrogen peroxide mixture) liquid, is supplied to the substrate, the charge in the device may There is a fear that the equipment may be rapidly moved from the equipment to the processing liquid (that is, discharged into the processing liquid), and the equipment may be damaged due to the heat generated by the movement.

Therefore, a substrate processing apparatus has been used conventionally (for example, Patent Document 1). This substrate processing apparatus includes a light source and a fan. The light source irradiates ultraviolet rays and is arranged in the air duct. The air duct is formed by a cylindrical member, for example. The fan blows air from one end of the cylindrical member toward the other end. The light source ionizes the gas flowing in the air duct by irradiating ultraviolet rays. The ions ejected from the other end of the air duct hit the substrate, whereby the static electricity of the substrate is neutralized. That is, the charge of the substrate can be removed.

    [Prior technical literature]         [Patent Literature]    

Patent Document 1: Japanese Patent Application Laid-Open No. 7-22530.

On the other hand, a substrate processing apparatus that irradiates the substrate with ultraviolet rays is also considered as another apparatus for removing electric charges from the substrate. This substrate processing apparatus includes an ultraviolet irradiator and a substrate holding unit. The substrate holding portion holds a substrate horizontally. The ultraviolet irradiator is disposed so as to face the main surface of the substrate. The ultraviolet irradiator irradiates ultraviolet rays to the main surface of the substrate, thereby generating a photoelectric effect on the substrate, and electrons are released from the substrate. Thereby, the electric charge of a board | substrate can be removed.

However, when the electrons released from the substrate are accumulated in a space directly above the substrate, the electrons in the space repel each other and accumulate on the substrate again. In addition, the electrons in the space and the electrons accumulated in the substrate repel each other, whereby the electrons in the substrate are difficult to be released into the space. Moreover, this phenomenon causes a reduction in the yield of the static elimination treatment.

Therefore, the present invention aims to provide a substrate processing apparatus capable of improving the yield of a static elimination process.

In order to solve the above-mentioned problems, a first aspect of the substrate processing apparatus is a device that performs a process of reducing a charge amount of a substrate that has been charged. The substrate processing apparatus includes a substrate holding means, an ultraviolet irradiation means, and an electrostatic field forming means. The substrate holding means is used to hold a substrate. The ultraviolet irradiation means is disposed so as to face the substrate held by the substrate holding means with a space therebetween, and irradiates the substrate with ultraviolet rays. The means for forming an electrostatic field is to form an electric field in the space to keep the electrons released from the substrate away from the substrate.

The second aspect of the substrate processing apparatus is the substrate processing apparatus of the first aspect, wherein the electrostatic field forming means is provided with a first electrode and a direct current power source. The first electrode is disposed on the ultraviolet irradiation means side with respect to the substrate held by the substrate holding means. The DC power source applies a higher potential to the first electrode than the substrate holding means.

The third aspect of the substrate processing apparatus is the substrate processing apparatus of the second aspect, wherein the substrate holding means is grounded.

The fourth aspect of the substrate processing apparatus is the substrate processing apparatus of the second or third aspect, and further includes a switch. The open relationship switches the electrical connection / disconnection between the first electrode and the DC power source.

A fifth aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the second to fourth aspects, wherein the first electrode is disposed between the substrate held by the substrate holding means and the ultraviolet irradiation means, and the same The substrates face each other.

The sixth aspect of the substrate processing apparatus is the substrate processing apparatus of the fifth aspect, wherein the first electrode system has a linear shape, a grid shape, or a circumferential shape.

A seventh aspect of the substrate processing apparatus is a substrate processing apparatus of a sixth aspect, wherein the ultraviolet irradiation means has a pair of second electrodes. The pair of second electrodes are electrodes for generating ultraviolet rays, and are arranged to face each other in a direction in which the ultraviolet irradiation means and the substrate holding means are arranged. The second electrode on the substrate holding means side of the pair of second electrodes has a grid-like shape for passing ultraviolet rays. The first electrode system has a grid-like shape. The opening ratio of the first electrode is larger than the opening ratio of the second electrode on the substrate holding means side.

An eighth aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the second to seventh aspects, wherein the first electrode is formed of stainless steel, aluminum, aluminum alloy, or an alloy thereof.

The ninth aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the second to fourth aspects, wherein the first electrode is a transparent electrode and is disposed between the substrate held by the substrate holding means and the ultraviolet irradiation means between.

The tenth aspect of the substrate processing apparatus is any one of the first to ninth aspects, and further includes a gas supply means. The gas supply means is for supplying an inert gas into a space between the substrate held by the substrate holding means and the ultraviolet irradiation means.

The eleventh aspect of the substrate processing apparatus is the substrate processing apparatus of any one of the first to tenth aspects, and includes an exhaust unit for reducing the pressure of the air pressure around the substrate.

A first aspect of the substrate processing system is provided with a storage and holding unit for storing a substrate, a substrate processing unit for processing the substrate, and a space between the storage and holding unit and the substrate processing unit for reciprocating between the storage and holding unit and A substrate passing section through which a substrate passes between substrate processing sections. A substrate processing apparatus of any one of the first to eleventh aspects is provided with a substrate processing apparatus at a substrate passing portion.

A first aspect of the substrate processing method is a method for reducing a charged amount of a substrate that has been charged, and includes a first step to a third step. In the first step, the substrate is placed on a substrate holding means. In the second step, the substrate is irradiated with ultraviolet rays by the ultraviolet irradiation means, and the ultraviolet irradiation means is arranged so as to face the substrate held by the substrate holding means with a space therebetween. In the third step, the electrostatic field forming means forms an electric field in the aforementioned space to keep the electrons released from the substrate away from the substrate.

The second aspect of the substrate processing method is the substrate processing method of the first aspect of the substrate processing method, wherein the third step is performed before the second step.

According to the substrate processing apparatus, the substrate processing system, and the substrate processing method, the electrons released from the substrate due to ultraviolet irradiation are moved away from the space on the substrate by the electric field formed by the electrostatic field forming means. Therefore, the phenomenon that electrons released from the substrate stay in the space on the substrate and the substrate is recharged is suppressed. As a result, the yield of the static elimination process can be improved.

1‧‧‧ substrate holding means (substrate holding unit)

1a‧‧‧ Upper surface of substrate holding portion

1b‧‧‧ Side of substrate holding section

1c‧‧‧ Lower surface of substrate holding section

2‧‧‧Ultraviolet irradiation means (ultraviolet irradiator)

3‧‧‧ tube member

3a‧‧‧Inner peripheral surface of the tube member

3b‧‧‧ Outer peripheral surface of tube member

3c‧‧‧Cylinder member top surface

3d‧‧‧ the lower surface of the tube member

5‧‧‧ partition

7‧‧‧Control Department

8‧‧‧ Electrostatic field forming means (electrostatic field forming section)

10‧‧‧ substrate processing equipment

11‧‧‧slot

12‧‧‧ mobile agency

14‧‧‧ rotating mechanism

21‧‧‧Quartz glass plate

22, 23‧‧‧ electrode (second electrode)

42, 42a, 42b‧‧‧Gas supply department

51‧‧‧ bottom

53,321,322‧‧‧through holes

61‧‧‧Exhaust

81‧‧‧electrode (first electrode)

82‧‧‧DC Power Supply

83‧‧‧Switch

100‧‧‧ substrate processing system

110‧‧‧Receiving container holding section

120‧‧‧ Substrate passing section

121‧‧‧ Index Robot

122‧‧‧Pass

123‧‧‧Transport robot

124‧‧‧ Index Transfer Route

130, 130a, 130b, 130c, 130d ‧‧‧ substrate processing department

131‧‧‧fluid box

231, 811‧‧‧ opening

321a, 322a‧‧‧‧Opening

421, 421a, 421b, 611‧‧‧ Piping

422, 422a, 422b

423, 423a, 423b‧‧‧Gas container

H1‧‧‧Function space

W1‧‧‧ substrate

FIG. 1 is a diagram schematically showing an example of a configuration of a substrate processing system.

FIG. 2 is a diagram schematically showing an example of a configuration of a substrate processing apparatus.

FIG. 3 is a diagram schematically showing an example of a configuration of a substrate processing apparatus.

FIG. 4 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 5 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 6 is a flowchart showing an example of the operation of the substrate processing apparatus.

FIG. 7 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 8 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 9 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 10 is a diagram schematically showing an example of the configuration of an electrode.

FIG. 11 is a diagram schematically showing an example of the internal configuration of an ultraviolet irradiator and the configuration of an electrode.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

    First embodiment.    

<An example of the overall configuration of a substrate processing system>

FIG. 1 is a diagram schematically showing an example of the overall configuration of the substrate processing system 100. In addition, in each of Fig. 1 and subsequent drawings, for ease of understanding, the sizes or numbers of the respective parts are exaggerated or simplified as required.

The substrate processing system 100 is a device for applying various processes to a semiconductor substrate. The substrate processing system 100 includes, for example, a container holding section 110, a substrate passing section 120, and a substrate processing section 130. The container holding section 110 is configured to hold the substrate container. A plurality of substrates are housed in the substrate container. In the example of FIG. 1, a plurality of container holding portions 110 are provided, and the container holding portions 110 are arranged along a direction parallel to a horizontal plane (hereinafter also referred to as the X direction).

The substrate processing unit 130 is a device for applying a predetermined process to a substrate. In the example of FIG. 1, a plurality of substrate processing units 130 (substrate processing units 130 a to 130 d in the illustrated example) are provided. The substrate processing sections 130a to 130d each perform various processes on the substrate. For convenience of explanation, it is assumed that each substrate is processed in the order of the substrate processing sections 130a to 130d. For example, the substrate processing unit 130 a supplies a processing liquid (a processing liquid such as a chemical liquid, a rinse liquid, or an IPA (isopropyl alcohol) liquid) to the substrate. Thereby, the substrate is processed in accordance with the processing liquid. For the subsequent processing in the substrate processing section 130c, it is not desirable for electric charges to accumulate on the substrate. In addition, in the processing performed by the substrate processing unit 130b (for example, processing using IPA), an organic substance may remain as an impurity on the main surface of the substrate, and it is preferable to remove such organic substance.

The substrate passing portion 120 is located between the container holding portion 110 and each of the substrate processing portions 130a to 130d. The unprocessed substrate is delivered from the container holding section 110 to the substrate processing section 130a through the substrate passing section 120. The processed substrate subjected to the processing in the substrate processing unit 130a is delivered from the substrate processing unit 130a to the container holding unit 110 through the substrate passing unit 120 or to another substrate processing unit 130b. The chronological transfer of substrates between the substrate processing units 130b to 130d is also the same.

The substrate passing section 120 includes, for example, an indexer robot 121, a passing section 122, and a transfer robot 123. The index robot 121 can move back and forth in the X direction on the index transport path 124 described later. The index conveyance path 124 is a conveyance path extending in the X direction adjacent to the plurality of container holding units 110. The index robot 121 can stop on the index conveyance path 124 at a position facing each of the container holding units 110.

The indexing robot 121 includes, for example, an arm and a hand. The hand is set at the front end of the arm, and can hold or release the held substrate. By driving the arm, the hand can move back and forth in a direction parallel to the horizontal plane and perpendicular to the X direction (hereinafter also referred to as the Y direction). In the state where the indexing robot 121 is opposed to the container holding section 110, the index robot 121 can move the hand toward the container holding section 110 to take out the unprocessed substrate from the container holding section 110, or deliver the processed substrate to收 罐 住 部 110。 Receive container holder 110.

The passing portion 122 is located on the side opposite to the container holding portion 110 with respect to the index transfer path 124. For example, the passing portion 122 may be formed at a position facing the central portion in the X direction of the index conveyance path 124. For example, the passing portion 122 may include a mounting table or a rack on which the substrate is placed. The indexing robot 121 can rotate the arm 180 degrees on a horizontal plane. Thereby, the index robot 121 can move a hand toward the passing part 122. The indexing robot 121 can deliver the substrate taken out from the container holding section 110 to the passing section 122, or can take out the substrate already placed on the passing section 122 from the passing section 122.

The transfer robot 123 is provided on the side opposite to the index transfer path 124 with respect to the passing portion 122. A plurality of (four in FIG. 1) substrate processing units 130 are arranged so as to surround the transfer robot 123. In the example of FIG. 1, the adjacent fluid cartridges 131 are provided in the substrate processing units 130. The fluid cartridge 131 is capable of supplying a processing liquid to the adjacent substrate processing unit 130 and recovering the used processing liquid from the substrate processing unit 130.

The transfer robot 123 has arms and hands similar to the index robot 121. The transfer robot 123 can take out the substrate from the passing portion 122 or can deliver the substrate to the passing portion 122. In addition, the transfer robot 123 can deliver substrates to each substrate processing unit 130 or can take out substrates from each substrate processing unit 130. In addition, the index robot 121 and the transfer robot 123 can be regarded as a means for transferring a substrate.

With such a configuration, for example, the following outline operation can be performed. That is, each semiconductor substrate stored in the container holding section 110 is sequentially transferred to the passing section 122 by the index robot 121. Next, the substrate is sequentially transferred to the substrate processing units 130 a to 130 d by the transfer robot 123, and the substrate processing units 130 a to 130 d receive their respective processes. A series of processed substrates are returned to the container holding section 110 by the passing section 122 and the index robot 121.

<Substrate Processing Device>

FIG. 2 is a diagram schematically showing an example of the configuration of the substrate processing apparatus 10. This substrate processing apparatus 10 may be provided in the passing part 122, for example. FIG. 2 shows an example of the configuration of a cross section perpendicular to the Y direction. In addition, the substrate processing apparatus 10 does not necessarily need to be provided in the passing section 122, and may be provided as the substrate processing section 130d, for example. In other words, the substrate processing apparatus 10 may be provided as a part of the plurality of substrate processing units 130.

The substrate processing apparatus 10 includes a substrate holding section 1, a moving mechanism 12, an ultraviolet irradiator 2, an electrostatic field forming section 8, a tube member 3, a gas supply section 42, an exhaust section 61, and a control section 7.

<Board holding section>

The substrate holding portion 1 is a member that holds the substrate W1 horizontally. When the substrate W1 is a semiconductor substrate (that is, a semiconductor wafer), the substrate W1 has a substantially circular flat plate shape. The substrate holding portion 1 has a substantially cylindrical shape, and has an upper surface 1a, a side surface 1b, and a lower surface 1c. The side surface 1b connects the peripheral edge of the upper surface 1a and the peripheral edge of the lower surface 1c. A substrate W1 is placed on the upper surface 1 a of the substrate holding portion 1. The upper surface 1a has, for example, a circular shape, and its diameter is equal to or greater than the diameter of the substrate W1.

As illustrated in FIGS. 2 and 3, a pair of grooves 11 is formed on the upper surface 1 a. A hand of the indexing robot 121 or the transfer robot 123 is inserted into the pair of slots 11.

The substrate W1 is placed on the substrate holding portion 1 as follows. That is, the substrate W1 is transported to the substrate holding portion 1 in a state of being placed on a hand. Next, the hand is moved toward the substrate holding portion 1 from above. With this movement, the hand is inserted into the pair of grooves 11 from above. With this movement, the substrate W1 is placed on the substrate holding portion 1 and separated from the hand. After that, the indexing robot 121 or the transfer robot 123 moves the hand in the Y direction and pulls the hand out of the groove 11. Thereby, the substrate W1 is placed on the substrate holding portion 1.

The upper surface 1 a of the substrate holding portion 1 may have a plurality of protruding shapes (hereinafter referred to as protruding portions) protruding toward the substrate W1 in a region different from the groove 11. This protrusion is also called a pin. The protrusion has, for example, a cylindrical shape. When a protrusion is provided, the substrate W1 is supported by the tip of the protrusion. The substrate holding portion 1 (that is, the main body portion) other than the protruding portion is formed of, for example, a conductive resin or a conductive ceramic. The protruding portion is formed of, for example, quartz. The protruding portion may be made of the same material as the main body portion.

<Ultraviolet irradiator>

The ultraviolet irradiator 2 is arranged on the upper side (opposite to the substrate holding portion 1) with respect to the substrate W1. That is, the ultraviolet irradiator 2, the substrate W1, and the substrate holding portion 1 are arranged in the Z direction in this order. The ultraviolet irradiator 2 faces the substrate W1 through a space. The ultraviolet irradiator 2 generates ultraviolet rays, and can irradiate the ultraviolet rays to the main surface of the substrate W1 (the main surface opposite to the substrate holding portion 1). For example, an excimer UV (ultraviolet) lamp can be used as the ultraviolet irradiator 2. The ultraviolet irradiator 2 includes, for example, a quartz tube filled with a discharge gas (for example, a rare gas or a rare gas halogen compound) and a pair of electrodes. A gas system for discharge exists between a pair of electrodes. A high voltage is applied between a pair of electrodes at a high frequency, whereby the discharge gas is excited to become an excimer state. When the discharge gas returns from the excimer state to the ground state, ultraviolet rays are generated.

The ultraviolet irradiator 2 may be formed in a flat plate shape. The ultraviolet irradiator 2 is arrange | positioned with the attitude | position of the normal direction of the ultraviolet irradiator 2 along the Z direction, for example. In other words, the ultraviolet irradiator 2 is a surface light source arranged horizontally. Alternatively, the ultraviolet irradiator 2 may have a rod-like shape. For example, the ultraviolet irradiator 2 is arranged in an attitude in which the longitudinal direction of the ultraviolet irradiator 2 is along the X direction.

The ultraviolet irradiator 2 includes a quartz glass plate 21 for protection. The quartz glass plate 21 is provided on the substrate W1 side. The quartz glass plate 21 is transparent to ultraviolet rays, and has heat resistance and corrosion resistance. The quartz glass plate 21 can protect the ultraviolet irradiator 2 from external forces, and can also protect the ultraviolet irradiator 2 from the atmosphere between the ultraviolet irradiator 2 and the substrate W1. The ultraviolet rays generated by the ultraviolet irradiator 2 pass through the quartz glass plate 21 and irradiate the substrate W1.

As described later, the main surface of the substrate W1 on which electrons have accumulated is irradiated with ultraviolet rays, whereby the electrons are released from the substrate W1. This can reduce the amount of charge of the substrate W1. That is, it is possible to perform a static elimination process on the substrate W1.

<Mobile mechanism>

The moving mechanism 12 is capable of moving the substrate holding portion 1 in the Z direction. The moving mechanism 12 is capable of moving the substrate holding portion 1 at a first position where the substrate holding portion 1 is close to the ultraviolet irradiator 2 (see FIG. 3) and at a second position where the substrate holding portion 1 is away from the ultraviolet irradiator 2 (see FIG. 2). Move back and forth. As will be described later, the first position is the position of the substrate holding portion 1 when the substrate W1 is subjected to a process using ultraviolet rays, and the second position is the position of the substrate holding portion 1 when the substrate W1 is being received and received. The moving mechanism 12 can be a ball screw mechanism, for example. The moving mechanism 12 can also cover the surroundings with bellows.

<Rotation mechanism>

The rotation mechanism 14 rotates the substrate holding unit 1 with an axis passing through the center of the substrate W1 and along the Z direction as a rotation axis. Thereby, the substrate W1 held by the substrate holding portion 1 can be rotated. The rotation mechanism 14 includes, for example, a motor.

<Cylinder member and gas supply section>

The cylindrical member 3 has an inner peripheral surface 3a, an outer peripheral surface 3b, an upper surface 3c, and a lower surface 3d, and has a cylindrical shape. The upper surface 3c is a surface connecting the inner peripheral surface 3a and the outer peripheral surface 3b, and is a surface on the ultraviolet irradiator 2 side. The lower surface 3d is a surface connecting the inner peripheral surface 3a and the outer peripheral surface 3b, and is a surface on the opposite side from the ultraviolet irradiator 2. The diameter of the inner peripheral surface 3 a of the cylindrical member 3 is larger than the diameter of the side surface 1 b of the substrate holding portion 1. Referring to FIG. 3, the tube member 3 surrounds the substrate holding portion 1 from the outside in a state where the substrate holding portion 1 has stopped at the first position.

In a state where the substrate holding portion 1 has stopped at the first position (FIG. 3), the ultraviolet irradiator 2 irradiates ultraviolet rays. Thereby, the substrate W1 is subjected to a static elimination process using ultraviolet rays. On the other hand, in a state where the substrate holding portion 1 has stopped at the first position, the periphery of the substrate W1 is surrounded by the ultraviolet irradiator 2, the tube member 3, and the substrate holding portion 1. Therefore, the substrate W1 cannot be easily taken out from the substrate holding portion 1 in this state.

Here, the moving mechanism 12 moves the substrate holding section 1 to the second position (FIG. 2). Thereby, the board | substrate holding | maintenance part 1 is retracted from the inside of the inner peripheral surface 3a of the cylindrical member 3 in the direction away from the ultraviolet ray irradiator 2. In this second position, the substrate W1 is positioned vertically downward (opposite to the ultraviolet irradiator 2) with respect to the lower surface 3d of the cylindrical member 3. Therefore, the index robot 121 or the transfer robot 123 can be moved out of the substrate W1 without moving the substrate W1 in the Y direction without being hindered by the tube member 3. On the contrary, in a state where the substrate holding section 1 has stopped at the second position, the index robot 121 or the transfer robot 123 can place the substrate W1 on the substrate holding section 1.

Through-holes 321 and 322 are formed in the tube member 3. The through holes 321 and 322 pass through the cylindrical member 3 and communicate with a space (hereinafter also referred to as a working space) H1 between the ultraviolet irradiator 2 and the substrate W1. Specifically, one end of the through-holes 321 and 322 is open at the upper surface 3 c of the cylindrical member 3. At the position where the opening is formed, the upper surface 3c of the cylindrical member 3 faces the ultraviolet ray irradiator 2 through a gap. The space between each of the openings and the ultraviolet irradiator 2 is continuous with the working space H1. That is, the through holes 321 and 322 are in communication with the working space H1.

The other ends of the through holes 321 and 322 are opened on the outer peripheral surface 3 b of the cylindrical member 3. The other ends of the through holes 321 and 322 are connected to the gas supply unit 42. Specifically, the other end of the through-hole 321 is connected to the gas supply unit 42a, and the other end of the through-hole 322 is connected to the gas supply unit 42b. The gas supply units 42a and 42b are capable of supplying a gas such as oxygen or an inert gas (for example, nitrogen or argon) to the working space H1 through the through holes 321 and 322, respectively. That is, the through holes 321 and 322 function as a passage for air supply.

Each of the gas supply sections 42 a and 42 b includes a pipe 421, an on-off valve 422, and a gas storage container 423. Hereinafter, the piping 421, the on-off valve 422, and the gas receiving container 423 belonging to the gas supply unit 42a are referred to as a piping 421a, the on-off valve 422a, and the gas receiving container 423a, respectively. The container 423 is called a piping 421b, an on-off valve 422b, and a gas storage container 423b, respectively. The gas supply portions 42 a and 42 b are the same as each other except the connection end of the pipe 421. The gas storage containers 423a and 423b contain a gas to be supplied to the working space H1. The gas container 423a is connected to one end of the pipe 421a, and the gas container 423b is connected to one end of the pipe 421b. The on-off valve 422a is provided on the pipe 421a to switch the opening and closing of the pipe 421a, and the on-off valve 422b is provided on the pipe 421b to switch the opening and closing of the pipe 421b. The other end of the pipe 421a is connected to the other end of the through hole 321, and the other end of the pipe 421b is connected to the other end of the through hole 322.

<Static Field Formation Section>

The electrostatic field forming portion 8 forms an electric field in the working space H1. The direction of this electric field is the direction from the ultraviolet irradiator 2 side toward the substrate W1 side. Therefore, the electric field acts on the electrons released from the substrate W1 to the working space H1 by the irradiation of ultraviolet rays, and moves the electrons away from the substrate W1.

The electrostatic field forming section 8 includes an electrode 81, a DC power source 82, and a switch 83. In the examples of FIGS. 2 and 3, the electrode 81 is disposed between the ultraviolet irradiator 2 and the substrate W1. More specifically, the electrode 81 is attached to the lower surface of the quartz glass plate 21. The electrode 81 is conductive, and is formed of, for example, stainless steel, aluminum, aluminum alloy, copper, copper oxide, or an alloy thereof.

Incidentally, in the presence of oxygen in the working space H1, the oxygen may be changed into ozone by the ultraviolet rays of the ultraviolet irradiator 2. Since stainless steel, aluminum, and aluminum alloys do not pose a problem even when exposed to ozone, it is preferable to use any of these materials as the electrode 81 from this viewpoint.

This electrode 81 is opposed to only a part of the main surface of the substrate W1 in the Z direction. FIG. 4 is a plan view schematically showing an example of the configuration of the electrode 81. In the example of FIG. 4, the substrate W1 is represented by a two-dot chain line. In the example of FIG. 4, the electrode 81 has a grid-like shape when viewed in the Z direction. In other words, the electrode 81 has a flat plate shape extending in the XY plane, and the electrode 81 is formed with a plurality of openings 811 that penetrate the electrode 81 itself in the Z direction. In the example of FIG. 4, each of the openings 811 has a hexagonal shape, and other openings 811 are arranged in six places around one of the openings 811. That is, the electrode 81 has a honeycomb shape. The aspect of the plurality of openings 811 is not limited to this, and may be appropriately changed. For example, as shown in FIG. 5, each of the openings 811 may have a quadrangular shape, and other openings 811 may be arranged at four places around one opening 811. That is, the openings 811 may be arranged in a grid shape. In the examples of FIGS. 4 and 5, the electrode 81 is provided over the entire surface of the main surface of the substrate W1, for example. That is, in the case where it is assumed that the opening 811 is not provided, the electrode 81 has a breadth equivalent to that of the main surface of the substrate W1.

The ultraviolet rays from the ultraviolet irradiator 2 are irradiated onto the main surface of the substrate W1 through a region (for example, the opening 811) where the electrode 81 does not exist.

The DC power source 82 is connected between the electrode 81 and the substrate holding portion 1, and a potential higher than the potential of the substrate holding portion 1 is applied to the electrode 81. That is, the output terminal on the high potential side of the DC power source 82 is connected to the electrode 81 through the wiring, and the output terminal on the low potential side of the DC power source 82 is connected to the substrate holding unit 1. In the examples of FIGS. 2 and 3, the substrate holding portion 1 is grounded.

The switch 83 is, for example, a semiconductor switch or a relay, and is used to switch between the electrical connection / non-connection of the electrode 81, the DC power source 82, and the substrate holding portion 1. In the example of FIG. 1, the switch 83 is connected between the electrode 81 and the DC power source 82. The on / off of the switch 83 is controlled by the control unit 7.

When the switch 83 is turned on, a high potential terminal of the DC power source 82 is electrically connected to the electrode 81 and a high potential is applied to the electrode 81. Since a low potential is applied to the substrate holding portion 1 by the DC power source 82, an electric field is generated between the electrode 81 and the substrate holding portion 1 toward the substrate holding portion 1. That is, an electric field is generated in the working space H1 from the ultraviolet irradiator 2 side toward the substrate holding portion 1 side. When the switch 83 is closed, the electric field disappears.

<Closed space>

The substrate processing apparatus 10 may form a closed space. In the examples of FIGS. 2 and 3, the ultraviolet irradiator 2, the tube member 3, the partition wall 5, and the bottom portion 51 are connected to each other to form a closed space. The portion of the lower surface of the ultraviolet irradiator 2 on the peripheral edge side has a protrusion shape protruding on the side of the tube member 3. A portion on the outer peripheral side of the upper surface 3c of the cylindrical member 3 is connected to its protruding portion. The openings 321 a and 322 a of the through holes 321 and 322 are formed on the inner peripheral side of the upper surface 3 c and face the lower surface of the ultraviolet irradiator 2 with a gap in the Z direction. The partition wall 5 is connected to the lower surface 3d of the cylindrical member 3. The partition wall 5 extends in the Z direction and is connected to the bottom portion 51. That is, the ultraviolet irradiator 2, the tube member 3, the partition wall 5, and the bottom portion 51 can function as a chamber. A substrate holding portion 1, a moving mechanism 12, a rotating mechanism 14, and an electrode 81 are housed in a sealed space formed by the ultraviolet irradiator 2, the tube member 3, the partition wall 5, and the bottom portion 51.

<Exhaust>

A through-hole 53 for exhaust is formed in the partition wall 5. The through hole 53 penetrates the partition wall 5 in the X direction. The through hole 53 is connected to the exhaust portion 61. The exhaust portion 61 includes, for example, a pipe 611 connected to the through hole 53 and the like. The air inside the substrate processing apparatus 10 is exhausted to the outside through a pipe 611.

<Door>

A shutter (not shown) that functions as an entrance / exit for the substrate W1 is provided on the partition wall 5. By opening the shutter, the inside of the substrate processing apparatus 10 communicates with the outside. The index robot 121 or the transfer robot 123 can feed the substrate W1 into the substrate processing apparatus 10 through the opened door, and can also take out the substrate W1. When the substrate processing apparatus 10 is provided in the passing portion 122, a shutter for the index robot 121 and a shutter for the transfer robot 123 are provided.

<Control section>

The ultraviolet irradiator 2, the moving mechanism 12, the rotating mechanism 14, the on-off valve 422, the switch 33, and the shutter of the gas supply unit 42 are controlled by the control unit 7.

The control unit 7 is an electronic circuit device, and may include, for example, a data processing device and a storage medium. For example, the data processing device may be an arithmetic processing device such as a CPU (Central Processor Unit; central processing unit). The storage unit may also have non-transitory storage media (such as ROM (read only memory) or hard disc) and temporary storage media (such as random access memory (RAM) body)). For a non-transitory storage medium, for example, a program that prescribes a process executed by the control unit 7 may be stored. When the program is executed by the processing device, the control unit 7 can execute the processing specified in the program. As a matter of course, part or all of the processing executed by the control section 7 may be executed by hardware.

<Operation of Substrate Processing Device>

FIG. 6 is a flowchart showing an example of the operation of the substrate processing apparatus 10. Initially, the moving mechanism 12 stops the substrate holding section 1 at the second position (FIG. 2), and the switch 83 is turned off. Here, as an example, the exhaust system performed by the exhaust unit 61 is always performed. In step S1, the control unit 7 opens the shutter, controls the indexing robot 121 or the transfer robot 123, arranges the substrate W1 on the substrate holding unit 1, and closes the shutter.

The substrate W1 is negatively charged. For example, in a cleaning process in which pure water (DIW; deionized water) flows on the main surface of the substrate W1, most electrons move from the pure water to the silicon oxide film. Therefore, the possibility of negatively charging the substrate W1 after the cleaning process is high. Here, the substrate W1 which has been negatively charged is disposed on the substrate holding portion 1.

Next, in step S2, the control unit 7 controls the gas supply unit 42 (specifically, the on-off valve 422) to start the supply of gas. Thereby, gas is ejected from each of the openings 321a, 322a. For example, nitrogen can be used as the gas. In addition, the execution sequence of steps S1 and S2 may be reversed, and these may also be executed in parallel.

Next, in step S3, the control unit 7 controls the moving mechanism 12 so that the substrate holding unit 1 approaches the ultraviolet emitter 2 and stops at the first position. In the first position, the distance between the substrate W1 and the ultraviolet emitter 2 is, for example, several [mm] to several tens [mm]. As a more specific example, 3 [mm] can be used, for example. Also in this case, the thickness (thickness along the Z direction) of the electrode 81 is set to be thinner than 3 [mm]. This makes it possible to avoid collision between the electrode 81 and the substrate W1.

Next, in step S4, the control unit 7 controls the rotation mechanism 14 to start the rotation of the substrate W1. In step S5, the switch 83 is turned on. In step S6, the ultraviolet irradiator 2 starts ultraviolet irradiation.

In addition, the control unit 7 may execute a set of steps S4 to S6 when the atmosphere of the action space H1 becomes a predetermined atmosphere. For example, the control unit 7 counts the elapsed time from step S3. The elapsed time can be measured by a timing circuit such as a timer circuit. The control unit 7 determines whether the elapsed time is longer than a predetermined first predetermined period, and can also perform a set of steps S4 to S6 when making a positive determination. Alternatively, a sensor that measures the atmosphere of the working space H1 may be provided in the substrate processing apparatus 10. The control unit 7 may also determine whether the atmosphere of the working space H1 has a predetermined atmosphere based on the measured value.

Moreover, the execution order of steps S4 to S6 may be appropriately changed. Alternatively, at least any two of steps S4 to S6 may be performed in parallel.

The ultraviolet irradiator 2 irradiates ultraviolet rays to the substrate W1 (step S6), whereby the electric charges of the substrate W1 are removed. One of the reasons is that the photovoltaic effect can be considered to be generated on the substrate W1. In other words, electrons are released from the substrate W1 to the working space H1 by the irradiation of ultraviolet rays. For example, a wavelength of 252 [nm] or less can be adopted as the wavelength of ultraviolet rays. This is because the electric charge of the substrate W1 can be efficiently removed in this wavelength range. As a more efficient wavelength, a wavelength in the range of 172 ± 20 [nm] can be used.

In the example of FIG. 6, since the substrate W1 is rotated during irradiation of ultraviolet rays (steps S4 and S6), the main surface of the substrate W1 can be more uniformly irradiated with ultraviolet rays than when the substrate W1 is not rotated.

Further, during the irradiation of ultraviolet rays, the switch 83 is turned on (steps S5 and S6), so an electric field is generated in the working space H1 during the irradiation of ultraviolet rays. The direction of this electric field is the direction from the ultraviolet irradiator 2 side toward the substrate W1 side. Therefore, the electrons released from the substrate W1 move in a direction away from the substrate W1 due to the electric field. More specifically, the electrons move toward the electrode 81. The electron system flows from the electrode 81 to the ground through the switch 83 and the DC power source 82.

Therefore, it is possible to suppress the electrons released from the substrate W1 from being collected directly above the substrate W1. Therefore, it is possible to suppress a situation where electrons directly above the substrate W1 repel each other and accumulate on the substrate W1 again, that is, it is possible to suppress recharging of the substrate W1. Thereby, the yield of the static elimination process can be improved.

Next, in step S7, the control unit 7 determines whether or not the processing for the substrate W1 should be ended. For example, the control unit 7 may determine that the processing should end when the elapsed time from step S6 exceeds the second predetermined time. Alternatively, for example, a surface potentiometer for measuring the surface potential of the substrate W1 may be provided in the substrate processing apparatus 10, and the control unit 7 may determine based on the measured value. When it is determined that the processing for the substrate W1 should not be ended, the control unit 7 executes step S7 again. When it is determined that the processing should be ended, the control unit 7 controls the rotation mechanism 14 to stop the rotation of the substrate W1 in step S8, stops the ultraviolet irradiator 2 in step 8 and turns off the switch 83 in step S9. When the irradiation of ultraviolet rays is stopped, the static elimination of the substrate W1 is ended, and the electric field in the application space H1 disappears when the switch 83 is closed. The execution order of steps S8 to S10 can be appropriately changed. Alternatively, at least any two of steps S8 to S10 may be executed in parallel with each other.

As described above, according to the substrate processing apparatus 10, it is possible to increase the yield of the static elimination process.

Incidentally, if the ultraviolet intensity of the ultraviolet irradiator 2 is increased, the amount of electrons per unit time released from the substrate W1 is increased. Therefore, it can also be used to increase production. On the other hand, when oxygen is present in the working space H1, if the intensity of ultraviolet rays is increased, the amount of ozone generated by the ultraviolet rays acting on oxygen molecules also increases. Due to the strong oxidizing power of ozone, the surface of the substrate W1 easily changes properties. That is, if the intensity of ultraviolet rays is increased in order to increase the yield, the surface state of the substrate W1 is easily changed. According to this substrate processing apparatus 10, it is not necessary to increase the intensity of ultraviolet rays, and it is possible to increase the yield. In other words, according to the present substrate processing apparatus 10, the intensity of ultraviolet rays suitable for the surface state of the substrate W1 can be adopted regardless of the improvement of the yield.

Moreover, in the example of FIG. 6, step S5 is performed earlier than step S6. That is, an electric field is formed before the start of ultraviolet irradiation. Thereby, even immediately after the ultraviolet rays are irradiated, the electrons are quickly separated from the substrate W1. Therefore, compared with the case where an electric field is formed after the start of ultraviolet irradiation, the yield can be improved.

<Supply of Nitrogen>

In the above example, the gas supply unit 42 supplies an inert gas (for example, nitrogen) to the working space H1 (step S2). This can reduce the oxygen concentration in the working space H1. This advantage is explained next. Oxygen is more easily ionized than inert gases. Therefore, if the oxygen concentration in the working space H1 is high, there is a high possibility that electrons released from the substrate W1 will immediately act on oxygen molecules and become oxygen ions. Since the oxygen ions are heavier than the individual electrons, in this case, the oxygen ions are easily concentrated at a position close to the substrate W1. When electrons (ions) are collected near the substrate W1, the electrons easily return to the substrate W1.

On the other hand, when the oxygen concentration in the working space H1 is low and the concentration of the inert gas (nitrogen) is high, it can be considered that gas molecules act on the gas at a position farther away from the substrate W1 and are ionized. In the above example, the gas supply unit 42 supplies an inert gas (nitrogen) that is less easily ionized than oxygen to the working space H1 to reduce the oxygen concentration. Therefore, the electrons are ionized at a position farther from the substrate W1 than when the oxygen concentration is high. This also suppresses recharging of the substrate W1.

<Decompression>

The exhaust portion 61 may also suck the gas in the closed space and reduce the pressure of the air around the substrate W1. This can reduce the number of oxygen molecules in the working space H1. Therefore, it is difficult for electrons released from the substrate W1 to ionize oxygen, and it is difficult to collect the electrons directly above the substrate W1. In other words, the electrons are easily separated from the substrate W1. Therefore, recharge of the substrate W1 can be suppressed. In this case, the gas supply unit 42 may not be provided.

<Shape of electrode>

In the example described above, the electrode 81 has a grid-like shape, but may have a linear shape, for example. FIG. 7 is a plan view schematically showing another example of the configuration of the electrode 81. For example, the electrode 81 may have a linear shape extending in the X direction. In the example of Fig. 7, a plurality of electrodes 81 are provided. The plurality of electrodes 81 are spaced from each other and extend parallel to each other. The plurality of electrodes 81 are located on the main surface of the substrate W1 on the upper surface in the Z direction.

The ultraviolet rays from the ultraviolet irradiator 2 are irradiated onto the main surface of the substrate W1 through the plurality of electrodes 81. In the example of FIG. 6, the substrate W1 is represented by a two-dot chain line. The electron system released from the substrate W1 by the irradiation of ultraviolet rays moves to the electrode 81. It is not necessary to provide a plurality of electrodes 81, and a single electrode 81 may be provided.

FIG. 8 is a plan view schematically showing another example of the configuration of the electrode 81. Viewed from the Z direction, the electrode 81 extends in a meandering manner. In the example of FIG. 8, the electrode 81 alternately includes a portion extending in the X direction and a portion extending in the Y direction. In other words, the electrode 81 snakes linearly. The electrode 81 faces only a part of the main surface of the substrate W1. The ultraviolet rays from the ultraviolet irradiator 2 are irradiated to the main surface of the substrate W1 through a portion not facing the electrode 81. The electron system released from the substrate W1 by the irradiation of ultraviolet rays moves toward the electrode 81.

FIG. 9 is a plan view schematically showing another example of the configuration of the electrode 81. Viewed from the Z direction, the electrode 81 has a ring-like (circumferential) shape. In the example of FIG. 9, a plurality of the electrodes 81 are provided. The diameters of the plurality of electrodes 81 are different from each other, and they are arranged in a concentric circle shape at intervals from each other. In the example of FIG. 9, the plurality of electrodes 81 are arranged concentrically with the substrate W1. The plurality of electrodes 81 are opposed to the main surface of the substrate W1 in the Z direction. In the example of FIG. 9, the electrode 81 disposed on the outermost peripheral side faces the peripheral edge portion of the substrate W1 in the Z direction. The ultraviolet rays from the ultraviolet irradiator 2 pass between the plurality of electrodes 81 to irradiate the main surface of the substrate W1. The electron system released from the substrate W1 by the irradiation of ultraviolet rays moves toward the electrode 81. It is not necessary to provide a plurality of electrodes 81, and a single electrode 81 may be provided.

<Material of electrode>

In the above-mentioned example, the ultraviolet rays from the ultraviolet irradiator 2 are irradiated to the substrate W1 through an area where the electrode 81 is not provided, but it is not limited thereto. For example, the electrode 81 may have translucency to ultraviolet rays irradiated by the ultraviolet irradiator 2. More specifically, the electrode 81 may be a transparent electrode. For example, this electrode 81 is formed by depositing a material of a transparent electrode (for example, indium tin oxide) on quartz glass. In this case, the electrode 81 may also face the entire surface of the main surface of the substrate W1 in the Z direction. FIG. 10 is a diagram schematically showing an example of the configuration of the electrode 81. The electrode 81 has a circular shape, for example, and faces the entire surface of the main surface of the substrate W1. The ultraviolet rays from the ultraviolet irradiator 2 pass through the electrode 81 and are irradiated to the substrate W1. The electron system released from the substrate W1 by the irradiation of ultraviolet rays moves toward the electrode 81.

Thereby, the area of the electrode 81 viewed from the Z direction can be increased. That is, it is possible to widen the surface that receives electrons. Therefore, the electrode 81 easily receives electrons. Furthermore, the electric field can be formed uniformly.

<Position of electrode>

In the above example, the electrode 81 is disposed between the ultraviolet irradiator 2 and the substrate W1. However, it is not limited to this. For example, the electrode 81 may be disposed above the ultraviolet irradiator 2 (opposite to the substrate holding portion 1). Thereby, an electric field is also generated between the electrode 81 and the substrate holding portion 1. Therefore, the electrons released from the substrate W1 move toward the electrode 81. Since the quartz glass plate 21 of the ultraviolet irradiator 2 does not have conductivity, electrons may be accumulated in the quartz glass plate 21. Even in this case, since the electrons released from the substrate W1 can be kept away from the substrate W1, the electrons can be suppressed from returning to the substrate W1. In short, in the present substrate processing apparatus 10, the electrode 81 may be appropriately disposed at the position on the ultraviolet irradiator 2 side with respect to the substrate W1.

On the other hand, as shown in FIGS. 2 and 3, when the electrode 81 is disposed between the ultraviolet irradiator 2 and the substrate W1, the electronic system can flow from the electrode 81 to the switch 83 and the DC power source 82 to the ground. This can suppress the accumulation (charge) of electrons on the quartz glass plate 21 and the like. For example, this is better at the next point. That is, when an operator maintains the substrate processing apparatus 10, for example, it is not necessary to pay attention to the discharge caused by the charging of the member, and thus the work can be performed easily.

<Ultraviolet Irradiator and Electrode>

The ultraviolet irradiator 2 may have a grid-like electrode. FIG. 11 is a diagram schematically showing an example of the configuration of the ultraviolet irradiator 2. In FIG. 11, to simplify the drawing, only the pair of electrodes 22 and 23 and the quartz glass plate 21 are shown for the ultraviolet irradiator 2.

The electrode 22 has a flat plate shape that expands in the XY plane, and is formed of, for example, stainless steel, aluminum, aluminum alloy, copper, copper oxide, or an alloy thereof. The electrode 23 has, for example, a mesh shape. In other words, the electrode 23 has a flat plate shape that expands in the XY plane, and the electrode 23 has a plurality of openings 231 formed therethrough in the Z direction. The electrode 23 is disposed to face the electrode 22 at a distance from the electrode 22 in the Z direction. The electrode 23 is located on the quartz glass plate 21 side with respect to the electrode 22. The electrode 23 is formed of, for example, stainless steel, aluminum, aluminum alloy, copper, copper oxide, or an alloy thereof.

A discharge gas is present in the space between the electrodes 22 and 23. A high frequency and high voltage are applied between the electrodes 22 and 23. Thereby, the discharge gas is excited and becomes an excimer state. The discharge gas generates ultraviolet rays when it returns from the excimer state to the ground state. The ultraviolet rays pass through the openings 231 of the grid-shaped electrodes 23 and further pass through the quartz glass plate 21 to be irradiated to the outside (the substrate W1). The electrode 22 can also function as a light shielding portion with respect to ultraviolet rays. This avoids the situation where ultraviolet rays are radiated from the back (upper surface) side of the ultraviolet irradiator 2.

When the electrode 81 for forming an electric field has a grid-like shape, the aperture ratio of the electrode 81 may be set larger than the aperture ratio of the electrode 23 for ultraviolet rays. Thereby, the ultraviolet rays which have passed through the opening 231 of the electrode 23 can be more efficiently passed to the substrate W1 side. The opening ratio of the electrode 23 herein is a ratio of the total area of the openings 231 to the area of the entire electrode 23 (that is, the area surrounded by the outline on the outside of the electrode 23). The aperture ratio of the electrode 81 is also the same.

<Point light source>

The ultraviolet irradiator 2 may be configured by a plurality of point light sources. Each of the plurality of point light sources generates ultraviolet rays. In this case, unevenness occurs in the intensity distribution of ultraviolet rays on the substrate W1. In this case, it is preferable that the electrode 81 has a grid shape. The electrode 81 can scatter or diffract ultraviolet rays from various point light sources, and make the intensity distribution of the ultraviolet rays irradiated on the substrate W1 more uniform.

Further, when a mesh-like member for scattering or diffraction is provided between the ultraviolet irradiator 2 and the electrode 81, the aperture ratio of the electrode 81 can be set to be higher than the aperture ratio of the mesh-like member Bigger. Thereby, the ultraviolet rays which have passed through the mesh-shaped member can be more effectively transmitted to the substrate W1 side.

    Modification.    

When the case of the ultraviolet irradiator 2 is made of metal, the case may be grounded. In this case, the thunder pole 81 may be smaller than the exposed surface of the quartz glass plate 21 when viewed from the Z direction.

Although the present invention has been shown and described in detail, the above description is illustrative rather than restrictive in all aspects. Therefore, within the scope of the present invention, the present invention can be appropriately modified or omitted.

Claims (14)

A substrate processing device for reducing a charged amount of a substrate on a charged substrate, comprising: a substrate holding means for holding the substrate; and an ultraviolet irradiation means to match the foregoing held by the substrate holding means. The substrates are arranged facing each other across a space to irradiate the substrate with ultraviolet light; an electrostatic field forming means for forming an electric field in the space to keep electrons released from the substrate away from the substrate; An inert gas is supplied to the space between the substrate held by the substrate holding means and the ultraviolet irradiation means. The substrate processing apparatus according to claim 1, wherein the electrostatic field forming means includes: a first electrode disposed on the ultraviolet irradiation means side with respect to the substrate held by the substrate holding means; and a DC power supply, A higher potential is applied to the first electrode than the substrate holding means. The substrate processing apparatus according to claim 2, wherein the substrate holding means is grounded. The substrate processing apparatus according to claim 2, further comprising a switch for switching between electrical connection and electrical disconnection between the first electrode and the DC power source. The substrate processing apparatus according to claim 2, wherein the first electrode is disposed between the substrate held by the substrate holding means and the ultraviolet irradiation means, and faces the substrate. The substrate processing apparatus according to claim 5, wherein the first electrode system has a linear shape, a grid shape, or a circumferential shape. The substrate processing apparatus according to claim 2, wherein the first electrode is made of stainless steel, aluminum, an aluminum alloy, or an alloy thereof. The substrate processing apparatus according to claim 2, wherein the first electrode is a transparent electrode and is disposed between the substrate held by the substrate holding means and the ultraviolet irradiation means. A substrate processing device for reducing a charged amount of a substrate on a charged substrate, comprising: a substrate holding means for holding the substrate; and an ultraviolet irradiation means to match the foregoing held by the substrate holding means The substrates are arranged to face each other across a space to irradiate the substrate with ultraviolet rays; and an electrostatic field forming means for forming an electric field in the space to keep electrons released from the substrate away from the substrate; the electrostatic field forming means is The first electrode is disposed on the ultraviolet irradiation means side with respect to the substrate held by the substrate holding means; and the DC power supply applies a higher potential to the first electrode than the substrate holding means; The electrode is disposed between the substrate held by the substrate holding means and the ultraviolet irradiation means and faces the substrate. The ultraviolet irradiation means includes a pair of second electrodes for generating ultraviolet rays. The arrangement of the irradiation means and the substrate holding means The second electrode system on the substrate holding means side of the pair of second electrodes has a grid-like shape for passing ultraviolet rays; the first electrode system has a grid-like shape; The aperture ratio of one electrode is larger than the aperture ratio of the second electrode on the substrate holding means side. The substrate processing apparatus according to any one of claims 1 to 9, further comprising: a tube member for enclosing the space between the substrate held by the substrate holding means and the ultraviolet irradiation means; and The cylindrical member is formed with a through hole that penetrates itself and communicates with the space; the gas supply means supplies the inert gas to the space through the through hole. The substrate processing apparatus according to any one of claims 1 to 9, further comprising: an exhaust unit for decompressing the air pressure around the substrate. A substrate processing system is provided with: a storage and holding section for accommodating a substrate; a substrate processing section for processing a substrate; and a substrate passing section located between the storage and holding section and the substrate processing section for round trip The substrate passing between the storage and holding section and the substrate processing section; and the substrate processing device according to any one of claims 1 to 9 is provided in the substrate passing section. A substrate processing method is to reduce the amount of charge of the substrate on a charged substrate, and includes the following steps: a first step of disposing the substrate in a substrate holding means; a second step of irradiating the substrate with ultraviolet rays The ultraviolet irradiation means is disposed so as to oppose the substrate held by the substrate holding means with a space therebetween. In the third step, the electrostatic field forming means forms an electric field in the space to be released from the substrate. And a fourth step of supplying an inert gas to the space between the substrate held by the substrate holding means and the ultraviolet irradiation means. The substrate processing method according to claim 13, wherein the third step is performed before the second step.