Substrate processing device

Abstract

To suppress a second main surface from being contaminated by processing liquid that contains metal removed by etching.SOLUTION: A substrate processing device 1 includes: a substrate holding part for holding a substrate 9 that has a first main surface 91 and a second main surface 92 and that is provided with a metal film 96 on the first-main-surface 91 side of a peripheral edge part 93; an electrode unit 5 that has a first electrode 51 and a second electrode 52, the electrode unit being such that, when etching is performed, the first electrode 51 is positioned near the peripheral edge part 93 on the first-main-surface side 91, and the second electrode 52 separates from the first electrode 51 and approaches the substrate 9; a processing liquid filling part 6 that fills a gap between the substrate 9 and the first and second electrodes 51, 52 with processing liquid L1; a power supply 50 that performs etching by applying a voltage between the first electrode 51 and the second electrode 52; a rotation mechanism that rotates the substrate 9 relative to the electrode unit 5; and an auxiliary fluid nozzle 81 that, when etching is performed, jets auxiliary fluid oriented toward the radially outward side relative to the peripheral edge part 93, on the second-main-surface side 92 of the substrate 9.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a substrate processing apparatus. [Background technology]

[0002] Conventionally, in the manufacturing process of semiconductor substrates (hereinafter simply referred to as "substrates"), various processes are performed on the substrates. For example, in the substrate processing apparatuses of Patent Documents 1 and 2, a processing liquid is discharged by a processing liquid supply unit to a plurality of different positions on a substrate on which a precious metal film has been formed, and the precious metal film on the substrate is etched by contacting an anode with the processing liquid at one position and contacting a cathode with the processing liquid at another position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-158300 [Patent Document 2] Patent Publication No. 2023-8390 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in a substrate having a first main surface and a second main surface, when a metal film is provided on the first main surface side in the peripheral portion, as in Patent Documents 1 and 2, when electrolytic etching is performed on the metal film, the metal constituting the metal film loses electrons to become ions and dissolves in the treatment liquid. In this case, if the treatment liquid flows around to the second main surface side and spreads inward beyond the peripheral portion, the second main surface of the substrate will be contaminated by the metal.

[0005] The present invention has been made in view of the above-mentioned problems, and has an object to prevent the second main surface from being contaminated by a processing liquid containing a metal removed by etching. [Means for solving the problem]

[0006] A first aspect of the present invention is a substrate processing apparatus that etches a peripheral portion of a substrate, the apparatus comprising: a substrate holding section that holds a disk-shaped substrate having a first main surface and a second main surface, the substrate having a metal film provided on the first main surface side of the peripheral portion; an electrode unit having a first electrode and a second electrode, the first electrode being located near the peripheral portion on the first main surface side and the second electrode being spaced from the first electrode and located near the substrate when etching; a processing liquid filling section that fills a processing liquid between the first electrode and the second electrode and the substrate; a power source that etches a portion of the metal film located near the first electrode by applying a voltage between the first electrode and the second electrode; a rotation mechanism that rotates the substrate relative to the electrode unit to move the portion of the peripheral portion to be etched in a circumferential direction; and an auxiliary fluid nozzle that sprays an auxiliary fluid radially outward from the peripheral portion on the second main surface side of the substrate when etching.

[0007] A second aspect of the present invention is the substrate processing apparatus of the first aspect, wherein the auxiliary fluid is a gas.

[0008] A third aspect of the present invention is the substrate processing apparatus of the first aspect, wherein the auxiliary fluid is the processing liquid.

[0009] A fourth aspect of the present invention is a substrate processing apparatus according to the first aspect (which may be any one of the first to third aspects), wherein, when performing etching, the first electrode and the second electrode face a target portion which is a part of the peripheral portion of the substrate, and the processing liquid filling section ejects the processing liquid from an outlet, thereby forming a liquid filled state in which the processing liquid fills the space between the target portion, the first electrode, and the second electrode.

[0010] A fifth aspect of the present invention is a substrate processing apparatus according to the fourth aspect, further comprising an electrode moving mechanism for moving the electrode unit, the electrode moving mechanism moving a member having the outlet in the processing liquid filling section and the auxiliary fluid nozzle together with the electrode unit.

[0011] A sixth aspect of the present invention is a substrate processing apparatus for etching a peripheral portion of a substrate, the apparatus comprising: a substrate holding section for holding a substrate in a horizontal position, the substrate being disk-shaped and having a first main surface and a second main surface, the substrate having a metal film provided on the first main surface side of the peripheral portion; an electrode unit having a first electrode and a second electrode, the first electrode being located near a target portion that is part of the peripheral portion on the first main surface side facing upward and the second electrode being opposed to the target portion on the second main surface side facing downward; a processing liquid filling section for ejecting processing liquid from an outlet to form a liquid filled state in which the processing liquid is filled between the target portion, the first electrode and the second electrode; a power source for etching the metal film on the target portion by applying a voltage between the first electrode and the second electrode; and a rotation mechanism for moving the target portion on the peripheral portion in a circumferential direction by rotating the substrate relatively to the electrode unit, the side of the second electrode including an area that is lyophilic with respect to the processing liquid.

[0012] A seventh aspect of the present invention is a substrate processing apparatus of a sixth aspect, wherein the second electrode comprises an electrode body and a lyophilic member covering at least the radially inner area of ​​a side of the electrode body, and the lyophilic area is the surface of the lyophilic member.

[0013] An eighth aspect of the present invention is the substrate processing apparatus of any one of the fourth to seventh aspects, wherein the first electrode and the second electrode at least partially overlap when viewed along a direction perpendicular to a main surface of the substrate. Effect of the Invention

[0014] According to the present invention, it is possible to prevent the second main surface from being contaminated by a processing liquid containing a metal removed by etching. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing a layout of a substrate processing system. [Diagram 2]1 is a diagram showing a configuration of a substrate processing apparatus according to a first embodiment. [Diagram 3] FIG. 2 is a diagram showing the vicinity of an electrode unit disposed at a processing position. [Figure 4] 1 is a diagram showing a flow of substrate processing in a substrate processing apparatus; [Diagram 5] FIG. 13 is a diagram showing the vicinity of an electrode unit in a substrate processing apparatus of a comparative example. [Figure 6] FIG. 2 is a diagram showing the vicinity of an electrode unit in the substrate processing apparatus. [Figure 7] FIG. 13 is a diagram showing another example of the substrate processing apparatus. [Figure 8] FIG. 11 is a plan view showing another example of the electrode unit. [Figure 9] FIG. 11 is a cross-sectional view showing another example of the electrode unit. [Figure 10] FIG. 11 is a cross-sectional view showing another example of the electrode unit. [Figure 11] FIG. 13 is a diagram showing a substrate processing apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] 1 is a diagram showing the layout of a substrate processing system 10. The substrate processing system 10 is a system that processes a disk-shaped semiconductor substrate 9 (hereinafter simply referred to as "substrate 9"). The substrate processing system 10 includes an indexer block 101 and a processing block 102 coupled to the indexer block 101.

[0017] The indexer block 101 includes a carrier holding unit 104, an indexer robot 105, and an IR movement mechanism 106. The carrier holding unit 104 holds a plurality of carriers 107, each capable of accommodating a plurality of substrates 9. The plurality of carriers 107 (e.g., FOUPs) are held by the carrier holding unit 104 in a state arranged in a predetermined carrier arrangement direction. The IR movement mechanism 106 moves the indexer robot 105 in the carrier arrangement direction. The indexer robot 105 performs an unloading operation to unload the substrate 9 from the carrier 107, and a loading operation to load the substrate 9 into the carrier 107. The substrate 9 is transported in a horizontal position by the indexer robot 105.

[0018] The processing block 102 includes a plurality of (for example, four or more) processing units 108 that process the substrate 9, and a center robot 109. The processing units 108 are arranged to surround the center robot 109 in a plan view. The processing units 108 perform various processes on the substrate 9. A substrate processing apparatus described below is one of the processing units 108. The center robot 109 transfers the substrate 9 to and from the indexer robot 105. The center robot 109 also performs a loading operation to load the substrate 9 into the processing unit 108 and an unloading operation to unload the substrate 9 from the processing unit 108. The center robot 109 also transports the substrate 9 between the processing units 108. The substrate 9 is transported by the center robot 109 in a horizontal position.

[0019] Fig. 2 is a diagram showing the configuration of the substrate processing apparatus 1 according to the first embodiment. Fig. 2 shows a part of the configuration of the substrate processing apparatus 1 in a cross section taken along a plane including a predetermined central axis J1. The substrate processing apparatus 1 is a single-wafer type apparatus that processes substrates 9 one by one, and performs electrolytic etching on a peripheral portion 93 of the disk-shaped substrate 9. The peripheral portion 93 of the substrate 9 includes an edge end face (apex), a bevel portion, and portions of a first main surface 91 and a second main surface 92, which will be described later, near the bevel portion.

[0020] The substrate processing apparatus 1 includes a spin chuck 2, a cleaning liquid supply unit 3, a cup unit 4, an electrode unit 5, a processing liquid filling unit 6, an electrode moving unit 7, an auxiliary fluid jetting unit 8, a housing 11, and a control unit 19. The spin chuck 2, a part of the cleaning liquid supply unit 3, the cup unit 4, the electrode unit 5, a part of the processing liquid filling unit 6, a part of the electrode moving unit 7, and a part of the auxiliary fluid jetting unit 8 are accommodated in the internal space of the housing 11. An airflow forming unit 12 is provided in the canopy of the housing 11 to supply gas to the internal space and form an airflow (so-called downflow) flowing downward. For example, an FFU (fan filter unit) is used as the airflow forming unit 12. The control unit 19 is disposed outside the housing 11 and controls each component of the substrate processing apparatus 1. The control unit 19 is realized by, for example, a computer having a CPU, a memory, etc. executing a predetermined program. A part or the whole of the control unit 19 may be realized by a programmable logic controller (PLC) or the like.

[0021] The spin chuck 2 shown in FIG. 2 includes a chuck section 21 and a rotation mechanism 22. The chuck section 21 is a substrate holding section that is substantially disk-shaped and centered on a central axis J1 extending substantially parallel to the vertical direction, and holds the substrate 9 in a horizontal position from below. The chuck section 21 is, for example, a vacuum chuck, and contacts and adsorbs the center of the lower main surface 92 of the substrate 9. Typically, the diameter of the chuck section 21 is smaller than the diameter of the substrate 9. The center of the substrate 9 on the chuck section 21 approximately overlaps with the central axis J1. In the following description, in the substrate 9 held in a horizontal position by the chuck section 21, the main surface 92 facing downward is referred to as the "second main surface 92," and the main surface 91 facing upward is referred to as the "first main surface 91." In addition, the radial direction and the circumferential direction centered on the central axis J1 are simply referred to as the "radial direction" and the "circumferential direction." The radial direction is also the radial direction of the substrate 9, and the circumferential direction is also the circumferential direction of the substrate 9.

[0022] A metal film 96, which is a processing target in the substrate processing apparatus 1, is provided on the first main surface 91 side of the peripheral portion 93 of the substrate 9. The thickness of the metal film 96 is, for example, several tens of nm. The metal film 96 is provided on all or a part of the peripheral portion 93. On the first main surface 91 side, the metal film 96 may be present at least in the peripheral portion 93, and may be present in an area inside the peripheral portion 93 in addition to the peripheral portion 93. The metal film 96 may extend over substantially the entire first main surface 91 of the substrate 9. The metal film 96 may be present on the second main surface 92 side in addition to the first main surface 91 side. In FIG. 2, the metal film 96 is indicated by a thick line. The metal film 96 includes, for example, ruthenium (Ru). The metal film 96 may be a film including a ruthenium compound other than a film of simple ruthenium. The metal film 96 may also be a film including a metal other than ruthenium. In this embodiment, the metal film 96 includes ruthenium.

[0023] The rotation mechanism 22 is disposed below the chuck portion 21. The rotation mechanism 22 rotates the substrate 9 together with the chuck portion 21 about the central axis J1. The rotation mechanism 22 includes a shaft 221 and a motor 222. The shaft 221 is a substantially columnar or cylindrical member centered on the central axis J1. The shaft 221 extends in the vertical direction and is connected to the center of the lower surface of the chuck portion 21. The motor 222 is an electric rotary motor that rotates the shaft 221. The rotation mechanism 22 may be a motor having another structure (for example, a hollow motor, etc.).

[0024] The cleaning liquid supply unit 3 includes a cleaning liquid nozzle 31 and a cleaning liquid supply source 32. The cleaning liquid nozzle 31 is supported by a nozzle moving mechanism (not shown). The nozzle moving mechanism has, for example, a motor and a ball screw, and moves the cleaning liquid nozzle 31 approximately horizontally between a supply position above the substrate 9 and a retracted position radially outward from the substrate 9. The cleaning liquid nozzle 31 is connected to the cleaning liquid supply source 32 via a cleaning liquid line provided with a valve 321. The cleaning liquid supply source 32 supplies the cleaning liquid to the cleaning liquid nozzle 31. The cleaning liquid is, for example, pure water such as DIW (deionized water). The cleaning liquid may be an organic solvent such as IPA, or another type of liquid.

[0025] The cup section 4 includes a cup 41 and a cup lifting mechanism (not shown). The cup 41 is an annular member centered on a central axis J1. The cup 41 is disposed around the entire circumference of the substrate 9 and the chuck section 21 in the circumferential direction, and covers the sides and the bottom of the substrate 9 and the chuck section 21. The cup 41 is a liquid receiving container that receives liquid that splashes from the rotating substrate 9 toward the surroundings. The inner surface of the cup 41 is formed of, for example, a water-repellent material. The cup 41 remains stationary in the circumferential direction regardless of whether the substrate 9 is rotating or stationary. A liquid drainage port (not shown) is provided at the bottom of the cup 41 to drain the liquid received in the cup 41 to the outside of the housing 11.

[0026] The cup lifting mechanism moves the cup 41 in the vertical direction relative to the chuck unit 21. The cup lifting mechanism has, for example, a motor or an air cylinder as a drive source. The cup 41 can be moved in the vertical direction between a processing position around the substrate 9 shown in FIG. 2 and a retracted position below the processing position by the cup lifting mechanism. The cup unit 4 may include multiple cups 41 stacked in the radial direction. When the cup unit 4 includes multiple cups 41, each of the multiple cups 41 can move independently in the vertical direction, and the multiple cups 41 are switched to be used to receive the liquid according to the type of liquid splashed from the substrate 9.

[0027] The electrode unit 5 includes a first electrode 51 and a second electrode 52. The first electrode 51 and the second electrode 52 are each rod-shaped or cylindrical and extend in the vertical direction. The first electrode 51 and the second electrode 52 are spaced apart in the vertical direction. The diameter of each of the electrodes 51, 52 is, for example, 2 mm or more and 20 mm or less, and preferably 4 mm or less. The material of each of the electrodes 51, 52 is, for example, platinum (Pt) or glassy carbon. The material of the electrodes 51, 52 may be other conductive materials that can be appropriately etched as described below.

[0028] As described later, the electrode unit 5 is supported by the electrode moving part 7, and is disposed at a processing position facing a part of the peripheral portion 93 when etching the peripheral portion 93 of the substrate 9. When the electrode unit 5 is disposed at the processing position, the first electrode 51 is disposed on the first main surface 91 side of the substrate 9, and the second electrode 52 is disposed on the second main surface 92 side of the substrate 9. In this embodiment, when viewed along the up-down direction, the first electrode 51 and the second electrode 52 have substantially the same size and are disposed at the same position. That is, when viewed in a plan view, substantially the entire first electrode 51 overlaps the entire second electrode 52. As described later, since etching of the metal film 96 is performed at a portion on the peripheral portion 93 facing the electrode unit 5, the portion is hereinafter referred to as a "target portion."

[0029] FIG. 3 is a diagram showing the vicinity of the electrode unit 5 arranged at the processing position. In FIG. 3, the substrate 9 is shown in cross section (cross section on a plane including the central axis J1). When the electrode unit 5 is arranged at the processing position, the surface 511 facing downward in the first electrode 51 is approximately parallel to the first main surface 91 of the substrate 9, and the surface 511 faces the peripheral portion 93 on the first main surface 91 side of the substrate 9. In addition, the surface 521 facing upward in the second electrode 52 is approximately parallel to the second main surface 92 of the substrate 9, and the surface 521 faces the peripheral portion 93 on the second main surface 92 side of the substrate 9. In the following description, the surface 511 of the first electrode 51 and the surface 521 of the second electrode 52 are referred to as "opposing surfaces 511, 521". In the example of FIG. 3, both the opposing surfaces 511, 521 are circular. A power source 50 is electrically connected to the first electrode 51 and the second electrode 52. When etching the peripheral portion 93, as described below, the processing liquid L1 is filled between the target portion of the peripheral portion 93, the first electrode 51, and the second electrode 52 by the processing liquid filling section 6, and a predetermined voltage is applied between the first electrode 51 and the second electrode 52.

[0030] As shown in FIG. 2, the processing liquid filling unit 6 includes a processing liquid nozzle 61, a processing liquid line 62, and a processing liquid supply source 63. The processing liquid nozzle 61 is supported by the electrode moving unit 7 together with the electrode unit 5. The processing liquid nozzle 61 is connected to the processing liquid supply source 63 via the processing liquid line 62. The processing liquid supply source 63 supplies the processing liquid L1 to the processing liquid nozzle 61. A valve 621 is provided in the processing liquid line 62. As shown in FIG. 3, the processing liquid nozzle 61 is disposed radially inward from the first electrode 51 on the first main surface 91 side of the substrate 9. The processing liquid nozzle 61 is inclined in the up-down direction so that the lower end where the discharge port 611 is provided is positioned radially outward from the upper end. The discharge port 611 opens toward the gap between the first electrode 51 and the peripheral portion 93. When etching the peripheral portion 93, the processing liquid L1 is discharged from the discharge port 611 toward the gap.

[0031] Typically, the treatment liquid L1 is an electrolyte, for example, an aqueous solution containing hydrogen chloride (HCl) or ammonium chloride (NH4Cl) as a solute. The concentration of the solute is, for example, 5 wt% or more, and preferably 10 wt% or more. The upper limit of the concentration of the solute is not particularly limited, but is, for example, 25 wt%. The electrolyte may contain additives, etc. The electrolyte may be non-aqueous.

[0032] As shown in FIG. 2, the auxiliary fluid jetting unit 8 includes an auxiliary fluid nozzle 81, an auxiliary fluid line 82, and an auxiliary fluid supply source 83. The auxiliary fluid nozzle 81 is supported by the electrode moving unit 7 together with the electrode unit 5. The auxiliary fluid nozzle 81 is connected to the auxiliary fluid supply source 83 via the auxiliary fluid line 82. The auxiliary fluid supply source 83 supplies the auxiliary fluid to the auxiliary fluid nozzle 81. A valve 821 is provided in the auxiliary fluid line 82. As shown in FIG. 3, the auxiliary fluid nozzle 81 is disposed radially inward from the second electrode 52 on the second main surface 92 side of the substrate 9. The auxiliary fluid nozzle 81 is inclined in the up-down direction so that the upper end where the jetting port 811 is provided is positioned radially outward from the lower end. The jetting port 811 opens toward the gap between the second electrode 52 and the peripheral portion 93. When etching the peripheral portion 93, the auxiliary fluid is jetted from the jetting port 811 toward the gap. An example of the auxiliary fluid is a gas, and in this embodiment, it is an inert gas such as nitrogen (N2) gas. Inert gases other than nitrogen gas are, for example, gases with low reactivity such as rare gases and carbon dioxide gas. Depending on the type of substrate 9, the auxiliary fluid may be a gas other than the inert gas.

[0033] As shown in FIG. 2, the electrode moving unit 7 includes a support unit 71, an arm unit 72, and an electrode moving mechanism 73. The support unit 71 supports the processing liquid nozzle 61, the auxiliary fluid nozzle 81, the first electrode 51, and the second electrode 52. In detail, as shown in FIG. 3, the support unit 71 includes a support unit main body 710 and an auxiliary moving mechanism 711. The auxiliary fluid nozzle 81 and the second electrode 52 are fixed to the support unit main body 710. The auxiliary moving mechanism 711 has a fixed body and a moving body, and the fixed body is fixed to the support unit main body 710. The moving body is movable in the vertical direction relative to the fixed body. The processing liquid nozzle 61 and the first electrode 51 are fixed to the moving body. In this way, the support unit 71 supports the processing liquid nozzle 61, the auxiliary fluid nozzle 81, the first electrode 51, and the second electrode 52 in a state in which the processing liquid nozzle 61 and the first electrode 51 are movable in the vertical direction relative to the auxiliary fluid nozzle 81 and the second electrode 52. The auxiliary movement mechanism 711 includes, for example, a motor and a ball screw, etc. The auxiliary movement mechanism 711 may be realized by a linear motor, etc.

[0034] The arm portion 72 is a member extending in the radial direction. A support portion 71 is attached to one end of the arm portion 72, and the other end is supported by an electrode moving mechanism 73. The electrode moving mechanism 73 has, for example, a motor and a ball screw, and can move the arm portion 72 in the radial direction (the longitudinal direction of the arm portion 72) and in the vertical direction. In other words, the electrode moving mechanism 73 moves the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 in the radial direction and the vertical direction. When etching the peripheral portion 93, the electrode moving mechanism 73 positions the electrode unit 5 together with the processing liquid nozzle 61 and the auxiliary fluid nozzle 81 at a processing position facing a part of the peripheral portion 93 of the substrate 9 (i.e., the target portion). When etching is completed, the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 are positioned at a retracted position radially outward of the substrate 9. The electrode moving mechanism 73 may be realized by a linear motor, etc.

[0035] Next, a flow of processing the substrate 9 in the substrate processing apparatus 1 will be described with reference to FIG. 4. In processing the substrate 9, each component is controlled by the control unit 19 in FIG. 2. First, the substrate 9 provided with the metal film 96 is carried into the substrate processing apparatus 1 and placed on the chuck unit 21 (step S11). The substrate 9 is held by the chuck unit 21 by vacuum suction. At this time, the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 are positioned at retracted positions that do not hinder the carrying in and out of the substrate 9. The same is true for the cleaning liquid nozzle 31. After carrying in the substrate 9, a cleaning process (pre-cleaning) of the substrate 9 may be performed in the same manner as in step S14 described later.

[0036] When the substrate 9 is held, the electrode moving mechanism 73 moves the arm portion 72, and the electrode unit 5 is disposed at the processing position together with the processing liquid nozzle 61 and the auxiliary fluid nozzle 81. As a result, as shown in FIG. 3, the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 face the target portion of the peripheral portion 93 of the substrate 9. In detail, the first electrode 51 is located near the target portion on the first main surface 91 side, and the second electrode 52 faces the target portion on the second main surface 92 side. In addition, the processing liquid nozzle 61 and the auxiliary fluid nozzle 81 are disposed radially inward of the first electrode 51 and the second electrode 52, respectively. The processing liquid nozzle 61 and the auxiliary fluid nozzle 81 are located at substantially the same circumferential position as the first electrode 51 and the second electrode 52. The distance between the opposing surface 511 of the first electrode 51 and the opposing surface 521 of the second electrode 52 and the substrate 9 (its peripheral portion 93) is adjusted to a few mm or less by the auxiliary movement mechanism 711. When the electrode unit 5 and the like are placed in the processing position, the rotation mechanism 22 starts to rotate the substrate 9 at a predetermined rotation speed.

[0037] Next, by opening the valve 621 of the processing liquid line 62 shown in FIG. 2, the processing liquid L1 is discharged from the discharge port 611 of the processing liquid nozzle 61 toward the gap between the first electrode 51 and the peripheral portion 93. As shown in FIG. 3, the processing liquid L1 enters the gap between the first electrode 51 and the peripheral portion 93 and fills the gap. A part of the processing liquid L1 may flow radially outward around the gap. The processing liquid L1 also flows around the second main surface 92 side of the peripheral portion 93 and fills the gap between the second electrode 52 and the peripheral portion 93 by capillary action. In this way, a liquid-filled state is formed in which the processing liquid L1 is filled between the target portion of the peripheral portion 93, the first electrode 51, and the second electrode 52. In the liquid-filled state, the processing liquid L1 continues uninterrupted between the target portion, the first electrode 51, and the second electrode 52. Excess processing liquid L1 flows downward and is collected by the cup 41. As long as the liquid-filled state is maintained, the supply of the processing liquid L1 from the processing liquid nozzle 61 to the peripheral portion 93 may be either continuous or intermittent.

[0038] Next, a predetermined voltage is applied between the first electrode 51 and the second electrode 52 by the power source 50. In the example of FIG. 3, a higher potential is applied to the second electrode 52 than to the first electrode 51, so that the first electrode 51 becomes a cathode and the second electrode 52 becomes an anode. By applying a voltage to the electrode unit 5, the metal film 96 is etched in the target portion of the peripheral portion 93 (step S12). In reality, the portion of the metal film 96 close to the cathode is preferentially etched. The reason why the metal film 96 is etched is not necessarily clear, but it is presumed that, for example, the following chemical reaction occurs between the first electrode 51 and the second electrode 52.

[0039] On the opposing surface 511 of the first electrode 51, 2H + +2e - →H2···(1) A chemical reaction occurs, represented by

[0040] On the first electrode 51 side of the metal film 96, Ru → Ru 3+ +3e - (2) 2Cl - →Cl2+2e - (3) 2H2O→O2+4H + +4e - (4) As a result, the metal film 96 dissolves in the processing liquid L1.

[0041] On the second electrode 52 side of the metal film 96, 2H + +2e - →H2···(5) A chemical reaction occurs, represented by

[0042] On the opposing surface 521 of the second electrode 52, 2Cl - →Cl2+2e - (6) 2H2O→O2+4H + +4e - (7) In an experiment in which a processing solution was filled between the metal film and the first and second electrodes and a voltage was applied to the processing solution via the first and second electrodes, it was confirmed that the metal film was actually etched.

[0043] In parallel with the etching of the metal film 96, the auxiliary fluid jetting unit 8 opens a valve 821 (see FIG. 2) to jet the auxiliary fluid from the jet port 811 of the auxiliary fluid nozzle 81 toward the target portion of the peripheral portion 93 in the radially outward direction (step S13). The auxiliary fluid flows toward the gap between the second electrode 52 and the peripheral portion 93 from the radially inner side, thereby preventing the processing liquid L1 from spreading radially inward from the gap. The surface of the processing liquid L1 between the second electrode 52 and the peripheral portion 93 may be pushed into the gap by the auxiliary fluid. Jetting of the auxiliary fluid from the auxiliary fluid nozzle 81 may be started before application of a voltage to the electrode unit 5.

[0044] As described above, the substrate 9 rotates with respect to the electrode unit 5, and the target portion in the peripheral portion 93 moves in the circumferential direction relative to the substrate 9. As a result, the metal film 96 is etched over the entire circumference of the peripheral portion 93. An imaging unit (not shown) is provided above the peripheral portion 93 of the substrate 9, and an image of the peripheral portion 93 is acquired over the entire circumference. The image of the peripheral portion 93 is input to the control unit 19, and the state of the peripheral portion 93 is confirmed. Specifically, it is confirmed whether or not the metal film 96 has been removed over the entire peripheral portion 93. The presence or absence of the metal film 96 in the peripheral portion 93 can be acquired by a known inspection algorithm. The presence or absence of the metal film 96 may be confirmed by other methods. For example, the presence or absence of the metal film 96 may be detected by measuring the current flowing between the second electrode 52 and the first electrode 51.

[0045] When the metal film 96 is removed from the entire peripheral portion 93, the application of voltage between the electrodes 51, 52 and the discharge of the processing liquid L1 from the processing liquid nozzle 61 are stopped, and etching is completed. The ejection of the auxiliary fluid from the auxiliary fluid nozzle 81 is also stopped. Thereafter, the electrode moving mechanism 73 moves the arm portion 72 radially outward, so that the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 move away from the peripheral portion 93 to the retreated position. The cleaning liquid nozzle 31 is disposed at a supply position above the substrate 9. Then, the cleaning liquid is supplied from the cleaning liquid nozzle 31 toward the center of the first main surface 91 of the substrate 9. The cleaning liquid spreads over the entire first main surface 91 of the substrate 9, and a cleaning process is performed in which the processing liquid L1 and the like adhering to the peripheral portion 93 of the substrate 9 are washed away (step S14). The cleaning liquid is scattered radially outward from the peripheral portion 93 of the substrate 9 by the centrifugal force caused by the rotation of the substrate 9, and is collected by the cup 41. The cleaning liquid nozzle 31 may eject the cleaning liquid toward the peripheral portion 93. In addition, another nozzle that ejects the cleaning liquid toward the second main surface 92 side of the peripheral portion 93 may be provided.

[0046] When the cleaning process of the substrate 9 has been performed for a predetermined time, the supply of the cleaning liquid from the cleaning liquid nozzle 31 to the substrate 9 is stopped. Then, the rotation speed of the substrate 9 is increased, and the cleaning liquid on the substrate 9 is shaken off and removed. That is, the drying process of the substrate 9 is performed (step S15). When the drying process of the substrate 9 is completed, the rotation of the substrate 9 is stopped. Thereafter, the substrate 9 is unloaded from the substrate processing apparatus 1 (step S16). With the above processes, the processing of the substrate 9 in the substrate processing apparatus 1 is completed.

[0047] As described above, the substrate processing apparatus 1 of FIG. 2 includes a substrate holding section (the chuck section 21 in the above), an electrode unit 5, a processing liquid filling section 6, a power source 50, a rotating mechanism 22, and an auxiliary fluid nozzle 81. The substrate holding section holds a disk-shaped substrate 9 having a first main surface 91 and a second main surface 92. A metal film 96 is provided on the first main surface 91 side of a peripheral portion 93 of the substrate 9. The electrode unit 5 includes a first electrode 51 and a second electrode 52. When etching is performed, the first electrode 51 is located near the peripheral portion 93 on the first main surface 91 side, and the second electrode 52 is spaced apart from the first electrode 51 and close to the substrate 9. The processing liquid filling section 6 fills the processing liquid L1 between the first electrode 51 and the second electrode 52 and the substrate 9. The power supply 50 applies a voltage between the first electrode 51 and the second electrode 52, thereby etching a portion of the metal film 96 located near the first electrode 51. The rotation mechanism 22 rotates the substrate 9 relative to the electrode unit 5, thereby circumferentially moving the portion of the peripheral portion 93 to be etched. The auxiliary fluid nozzle 81 is disposed on the second main surface 92 side of the substrate 9 at approximately the same circumferential position as the first electrode 51 during etching, and ejects auxiliary fluid radially outward toward the peripheral portion 93.

[0048] Here, a comparative substrate processing apparatus that omits the auxiliary fluid nozzle 81 is assumed. As described above, in the etching of the metal film 96, the metal constituting the metal film 96 loses electrons to become ions, which dissolve in the processing liquid L1. As shown in FIG. 5, most of the processing liquid L1 is discharged downward along the second electrode 52. However, the processing liquid L1 that has flowed around to the second main surface 92 side due to surface tension may spread inward from the gap between the second electrode 52 and the peripheral portion 93 (i.e., liquid dripping occurs), and the second main surface 92 of the substrate 9 may be contaminated by the metal. In this case, an external substrate transport mechanism or other devices that process the substrate 9 may be contaminated. In FIG. 5, the portion of the processing liquid L1 around the peripheral portion 93 where the concentration of the metal is high is shown in black (similar to FIG. 6 described later).

[0049] 6, in the substrate processing apparatus 1 provided with the auxiliary fluid nozzle 81, the auxiliary fluid ejected from the auxiliary fluid nozzle 81 inhibits the processing liquid L1 from spreading radially inward from the gap between the second electrode 52 and the peripheral portion 93 (prevents dripping). As a result, contamination of the second main surface 92 by the processing liquid L1 containing the metal removed by etching can be suppressed. Note that the auxiliary fluid nozzle 81 does not necessarily need to be disposed at the exact same circumferential position as the first electrode 51, and may be disposed at a position slightly shifted in the circumferential direction from the first electrode 51 within a range in which the processing liquid L1 containing the metal removed by etching can be suppressed from spreading radially inward on the second main surface 92 side.

[0050] Preferably, the substrate processing apparatus 1 further includes an electrode moving mechanism 73 for moving the electrode unit 5. The electrode moving mechanism 73 moves the processing liquid nozzle 61 and the auxiliary fluid nozzle 81 together with the electrode unit 5. This simplifies the configuration of the substrate processing apparatus 1 and reduces the manufacturing cost of the substrate processing apparatus 1 compared to a case where mechanisms for moving the processing liquid nozzle 61 and the auxiliary fluid nozzle 81 are separately provided. Depending on the design of the substrate processing apparatus 1, mechanisms for moving the processing liquid nozzle 61 and the auxiliary fluid nozzle 81 may be separately provided, or the positions of the electrode unit 5, the processing liquid nozzle 61, and the auxiliary fluid nozzle 81 may be fixed in the housing 11, and the electrode moving mechanism 73 may be omitted.

[0051] In the substrate processing apparatus 1 of FIG. 2, the auxiliary fluid may be a liquid. For example, the auxiliary fluid nozzle 81 may be connected to the processing liquid supply source 63, and in this case, the processing liquid L1 is ejected from the auxiliary fluid nozzle 81 as the auxiliary fluid. The processing liquid L1 enters the gap between the second electrode 52 and the peripheral portion 93 and inhibits the processing liquid L1 from spreading radially inward from the gap. In this way, the auxiliary fluid nozzle 81 ejects the processing liquid L1 toward the radially outward direction toward the peripheral portion 93 of the substrate 9, thereby making it possible to more reliably fill the processing liquid L1 between the second electrode 52 and the substrate 9 while suppressing contamination of the second main surface 92 by the processing liquid L1 containing the removed metal. The auxiliary fluid may be a liquid other than the processing liquid L1, for example, water. In this case, the processing liquid L1 between the electrodes 51, 52 and the substrate 9 is diluted by the water, so that the concentration of the processing liquid L1 ejected from the processing liquid nozzle 61 may be increased. On the other hand, when the auxiliary fluid is a gas as described above, it is possible to prevent the processing liquid L1 from being diluted by the auxiliary fluid, which would affect the etching.

[0052] Next, a description will be given of another method for suppressing the processing liquid L1 from spreading radially inward from the gap between the second electrode 52 and the peripheral portion 93. Fig. 7 is a diagram showing another example of the substrate processing apparatus 1, showing the vicinity of the electrode unit 5. In the substrate processing apparatus 1 of Fig. 7, the structure of the electrode unit 5 differs from that of the substrate processing apparatus 1 of Fig. 2, but the other configurations are similar to those of Fig. 2.

[0053] In the electrode unit 5 of FIG. 7, the side surface of the second electrode 52 includes a region having lyophilicity with respect to the treatment liquid L1. Specifically, the second electrode 52 includes an electrode body 520 and a lyophilic member 522. The electrode body 520 is rod-shaped or cylindrical and extends in the vertical direction, and is made of the electrode material described above. The end surface of the electrode body 520 facing the substrate 9 is the facing surface 521. The lyophilic member 522 is formed, for example, of a resin having lyophilicity with respect to the treatment liquid L1, and covers the side surface of the electrode body 520 (a surface substantially perpendicular to the main surfaces 91 and 92 of the substrate 9). In the example of FIG. 7, the lyophilic member 522 is cylindrical, and substantially the entire side surface of the electrode body 520 is covered with the lyophilic member 522, except for a region in the vicinity of the facing surface 521 on the side surface of the electrode body 520 (for example, a region within a distance of 0.1 to 2 mm from the facing surface 521). The lyophilic member 522 and the electrode body 520 are joined together by any method such as adhesion.

[0054] The lyophilicity of the lyophilic member 522 is higher than that of the electrode body 520 of the second electrode 52. The lyophilicity can be evaluated, for example, by measuring the contact angle of the treatment liquid L1. A sample having a flat surface made of the same material and in the same surface state as the lyophilic member 522 is prepared, and the treatment liquid L1 is dropped on the surface to measure the contact angle. The same applies to the electrode body 520. The contact angle of the lyophilic member 522 is smaller than that of the electrode body 520. The lyophilicity of the lyophilic member 522 is preferably higher than that of the second main surface 92 of the substrate 9. When the treatment liquid L1 is an aqueous solution, the lyophilic member 522 is a hydrophilic member having hydrophilicity, and the side surface of the second electrode 52 has hydrophilicity.

[0055] The processing liquid L1 discharged from the processing liquid nozzle 61 during etching enters the gap between the first electrode 51 and the peripheral portion 93, and also flows around to the second main surface 92 side of the peripheral portion 93, and also enters the gap between the second electrode 52 and the peripheral portion 93. Excess processing liquid L1 is drawn to the side surface of the second electrode 52 due to the lyophilicity of the lyophilic member 522. This prevents the processing liquid L1 from spreading radially inward from the gap between the second electrode 52 and the peripheral portion 93. The processing liquid L1 drawn to the side surface of the second electrode 52 flows downward along the side surface due to gravity.

[0056] As described above, in the substrate processing apparatus 1 of FIG. 7, the side surface of the second electrode 52 has lyophilicity, so that the processing liquid L1 containing the metal removed by etching can be prevented from spreading to the second main surface 92 and contaminating the second main surface 92. In addition, in the second electrode 52, the region near the opposing surface 521 on the side surface of the electrode body 520 is not covered by the lyophilic member 522, so that the lyophilic member 522 can be prevented from affecting the etching. Note that, when etching is not hindered, the region near the opposing surface 521 on the side surface of the electrode body 520 may be covered by the lyophilic member 522 together with other regions. In the example of FIG. 7, the auxiliary fluid nozzle 81 is omitted, but the auxiliary fluid nozzle 81 may be used in combination.

[0057] In the second electrode 52, the lyophilic member 522 does not necessarily need to be provided around the entire circumference of the side surface of the electrode body 520, and the lyophilic member 522 may be provided only on a part of the side surface of the electrode body 520. Even in this case, it is possible to suppress to some extent the treatment liquid L1 from spreading radially inward from the gap between the second electrode 52 and the peripheral portion 93. On the other hand, in order to effectively suppress the treatment liquid L1 from spreading radially inward from the gap, it is preferable that at least the radially inner region of the side surface of the electrode body 520 is covered with the lyophilic member 522. The "radially inner region" of the side surface of the electrode body 520 is, for example, a region of the side surface included in a range of 90° (preferably a range of 120°) centered on the direction from the center of the electrode body 520 toward the central axis J1.

[0058] In the above example, the surface of the lyophilic member 522 becomes a lyophilic region on the side surface of the second electrode 52, but the lyophilic member 522 may be omitted and the side surface of the electrode body 520 may have lyophilic properties. For example, by performing a predetermined lyophilic treatment (plasma treatment, etc.) on the side surface of the electrode body 520 of the second electrode 52, it is possible to improve the lyophilic properties of the side surface of the electrode body 520 compared to before the lyophilic treatment. This realizes the second electrode 52 including a region on the side surface that has lyophilic properties.

[0059] Incidentally, in the etching of the metal film 96 in the peripheral portion 93, as described above, the portion of the metal film 96 closest to the cathode is preferentially removed. In other words, it takes a certain amount of time to remove the portion of the metal film 96 closest to the anode. Therefore, depending on the position where the metal film 96 is attached, it may take a long time to remove the entire metal film 96 present in the peripheral portion 93.

[0060] Next, a description will be given of a preferred method for efficiently removing the entire metal film 96 present in the peripheral portion 93. In etching the metal film 96 in the peripheral portion 93, when a portion of the metal film 96 adjacent to the first electrode 51, which is the cathode, is removed, the first electrode 51 is moved slightly toward the substrate 9 by the auxiliary movement mechanism 711 shown in Fig. 3. This reduces the distance between the opposing surface 511 of the first electrode 51 and the metal film 96 remaining in the peripheral portion 93, making it possible to shorten the time required to remove the entire metal film 96 present in the peripheral portion 93.

[0061] At this time, the auxiliary movement mechanism 711 moves the processing liquid nozzle 61 together with the first electrode 51, so that the processing liquid L1 can be supplied to an appropriate position between the first electrode 51 and the substrate 9 even in a state in which the first electrode 51 is brought close to the remaining metal film 96. Depending on the design of the substrate processing apparatus 1, the auxiliary movement mechanism 711 may move only the first electrode 51. The timing at which the auxiliary movement mechanism 711 brings the first electrode 51 closer to the substrate 9 is determined based on, for example, an image of the peripheral portion 93 acquired by the imaging unit. The timing may be determined based on a current flowing between the second electrode 52 and the first electrode 51, or may be a predetermined time.

[0062] Also, instead of or together with the movement of the first electrode 51 by the auxiliary movement mechanism 711, the power source 50 may increase the voltage applied between the first electrode 51 and the second electrode 52. This can promote the removal of the portion of the metal film 96 away from the first electrode 51. Furthermore, after the portion of the metal film 96 adjacent to the first electrode 51, which is the cathode, is removed, the power source 50 may invert the cathode and the anode (invert the polarity of the first electrode 51 and the second electrode 52). This causes the electrode 51 facing the first main surface 91 to become the anode, and the electrode 52 facing the second main surface 92 to become the cathode. In other words, the electrode 52 becomes the first electrode in the vicinity of which etching of the metal film 96 occurs, and the electrode 51 becomes the second electrode. As a result, etching of the portion of the metal film 96 adjacent to the electrode 52 that has become the first electrode is accelerated, and it is possible to shorten the time required to remove the entire metal film 96 present in the peripheral portion 93 (i.e., the etching time). The above-described method for shortening the etching time may be adopted in other examples.

[0063] FIG. 8 is a plan view showing another example of the electrode unit 5. In FIG. 8, the processing liquid nozzle 61 is omitted. In the electrode unit 5 of FIG. 8, the second electrode 52 located on the second main surface 92 side of the substrate 9 is a rectangular plate. The surface facing upward in the second electrode 52 is a facing surface 521 facing the substrate 9, and is approximately parallel to the second main surface 92 of the substrate 9. The facing surface 521 of the second electrode 52 is larger than the facing surface 511 of the first electrode 51 (see FIG. 3). The area of ​​the facing surface 521 is, for example, two times or more, preferably three times or more, of the area of ​​the facing surface 511. Although the upper limit of the area of ​​the facing surface 521 is not particularly limited, if the facing surface 521 is excessively large, the weight of the second electrode 52 increases, so the area of ​​the facing surface 521 is, for example, 10 times or less than the area of ​​the facing surface 511. When viewed from above, the entire first electrode 51 overlaps the entire second electrode 52.

[0064] As described above, the opposing surface 521 of the second electrode 52 located on the second main surface 92 side of the substrate 9 is larger than the opposing surface 511 of the first electrode 51 located on the first main surface 91 side of the substrate 9, so that the retention of the processing liquid L1 on the second electrode 52 can be improved. As a result, it is possible to easily maintain a liquid-filled state in which the processing liquid L1 is filled between the target portion of the peripheral portion 93, the first electrode 51, and the second electrode 52. In addition, since the opposing surface 521 of the second electrode 52, which is an anode, is large, the reduction reaction on the opposing surface 521 is promoted compared to the electrode unit 5 of FIG. 3. As a result, the oxidation reaction on the opposing surface 511 of the first electrode 51 is also promoted, and the etching rate of the metal film 96 is improved. In the example of FIG. 8 as well, the auxiliary fluid nozzle 81 is provided (and / or the side surface of the second electrode 52 includes a region having lyophilicity), so that the second main surface 92 can be prevented from being contaminated.

[0065] FIG. 9 is a diagram showing another example of the electrode unit, and shows a cross section of the electrode unit 5a and the processing liquid nozzle 61. In the example of FIG. 9, the processing liquid nozzle 61 is a straight nozzle facing in the vertical direction, and when placed at the processing position, the processing liquid nozzle 61 is placed above the peripheral portion 93 of the substrate 9. The processing liquid nozzle 61 is formed of an insulating material such as resin. The first electrode 51 of the electrode unit 5a is a film of a conductive material provided on the inner circumferential surface of the processing liquid nozzle 61. In other words, the processing liquid nozzle 61 is an electrode-embedded nozzle. As in the example of FIG. 8, the second electrode 52 is plate-shaped. A power source 50 is connected to the first electrode 51 and the second electrode 52.

[0066] In etching the metal film 96 on the peripheral portion 93 of the substrate 9, the processing liquid L1 is continuously discharged from the discharge port 611 of the processing liquid nozzle 61. The processing liquid L1 covers the metal film 96 on the target portion of the peripheral portion 93 and collides with the second electrode 52. In other words, a liquid column of the processing liquid L1 formed downward from the discharge port 611 contacts both the target portion of the peripheral portion 93 and the second electrode 52. In reality, the processing liquid L1 also flows around the second main surface 92 side of the peripheral portion 93 and fills the gap between the second electrode 52 and the peripheral portion 93. In this way, a liquid-filled state in which the processing liquid L1 is filled between the target portion, the first electrode 51, and the second electrode 52 is maintained. The power source 50 applies a voltage between the first electrode 51 and the second electrode 52, thereby etching the metal film 96. Furthermore, by providing auxiliary fluid nozzle 81 (and / or by having the side surface of second electrode 52 include a region having lyophilicity), contamination of the second principal surface can be suppressed.

[0067] FIG. 10 is a cross-sectional view showing another example of the electrode unit. The electrode unit 5b shown in FIG. 10 includes a rectangular plate-shaped first electrode 51 and a rectangular plate-shaped second electrode 52. When the electrode unit 5b is disposed at the processing position, the first electrode 51 is located on the first main surface 91 side of the substrate 9, and the second electrode 52 is located on the second main surface 92 side of the substrate 9. The surface of the first electrode 51 facing downward is a facing surface 511 facing the substrate 9, which is approximately parallel to the first main surface 91 of the substrate 9. The surface of the second electrode 52 facing upward is a facing surface 521 facing the substrate 9, which is approximately parallel to the second main surface 92 of the substrate 9. The facing surface 511 of the first electrode 51 and the facing surface 521 of the second electrode 52 are approximately parallel to each other. The distance between the first electrode 51 and the second electrode 52 is slightly larger than the thickness of the substrate 9.

[0068] The electrode unit 5b further includes an insulating member 53. The insulating member 53 is, for example, in the shape of a block made of resin, and is disposed between an outer end of the first electrode 51 and an outer end of the second electrode 52 in the radial direction. The first electrode 51 and the second electrode 52 are fixed to the insulating member 53. A through hole is provided in the first electrode 51 radially inward of the insulating member 53. A connection member 622 is provided in the processing liquid line 62 (see FIG. 2) of the processing liquid filling unit 6 at an end opposite to the processing liquid supply source 63, and the connection member 622 is inserted into and fixed to the through hole of the first electrode 51. The connection member 622 has a discharge port 623 for the processing liquid L1, and the processing liquid L1 is supplied from the discharge port 623 to a space 54 (hereinafter referred to as "processing space 54") surrounded by the insulating member 53, the first electrode 51, and the second electrode 52. 10, the connection member 622, the first electrode 51, the insulating member 53, and the second electrode 52 are integrally configured as one member. In the support part 71 of the electrode movement part 7 (see FIG. 3), the auxiliary movement mechanism 711 is omitted, and the electrode unit 5b and the auxiliary fluid nozzle 81 are fixed to the support part main body 710.

[0069] When etching the peripheral portion 93 of the substrate 9, the electrode unit 5b and the connection member 622 are disposed at the processing position, so that the peripheral portion 93 is inserted into the processing space 54 from the radially inner side. The processing liquid L1 is discharged from the outlet 623 of the connection member 622, and the processing space 54 is filled with the processing liquid L1. That is, a liquid-filled state is formed in which the processing liquid L1 is filled between the target portion of the peripheral portion 93, the first electrode 51, and the second electrode 52. Then, the power source 50 applies a voltage between the first electrode 51 and the second electrode 52, so that the metal film 96 is etched. In addition, by providing the auxiliary fluid nozzle 81 (and / or by including a region in which the side surface of the second electrode 52 has lyophilicity), it is possible to prevent the second main surface 92 from being contaminated. Note that, as long as the liquid-filled state is maintained in the processing space 54, the processing liquid L1 may be discharged from the outlet 623 continuously or intermittently.

[0070] As described above, in the electrode unit 5b shown in FIG. 10, the insulating member 53 is disposed between the first electrode 51 and the second electrode 52 outside the peripheral portion 93 of the substrate 9, and the first electrode 51 and the second electrode 52 are fixed to the insulating member 53. The processing liquid filling section 6 supplies the processing liquid L1 from the discharge port 623 to the processing space 54 surrounded by the insulating member 53, the first electrode 51, and the second electrode 52. This makes it possible to easily and reliably form a liquid-filled state, and to appropriately etch the metal film 96 on the peripheral portion 93. In addition, the electrode moving mechanism 73 moves the member (the connection member 622 in the above example) having the discharge port 623 in the processing liquid filling section 6 and the auxiliary fluid nozzle 81 together with the electrode unit 5b. This makes it possible to simplify the configuration of the substrate processing apparatus 1.

[0071] In the substrate processing apparatus 1, the substrate 9 does not necessarily need to be held in a horizontal position, and may be held in an upright state, for example. When the substrate 9 is held upright in the substrate processing apparatus 1 of FIG. 10, the orientation of the electrode unit 5b is changed so that the insulating member 53 is disposed below the upright substrate 9 (a state in which FIG. 10 is rotated 90° clockwise). In the electrode unit 5b of FIG. 10, the first electrode 51 may be located on the first main surface 91 side, and the second electrode 52 may be located on the radial outside of the substrate 9. Furthermore, on the first main surface 91 side of the substrate 9, the first electrode 51, the insulating member 53, and the second electrode 52 may be provided side by side in the circumferential direction. In this case, the radial outside of the peripheral portion 93 and the second main surface 92 side are covered with another insulating member to form the processing space 54.

[0072] On the other hand, in order to increase the etching rate of the metal film 96 of the peripheral portion 93, it is preferable that the first electrode 51 is located on the first main surface 91 side of the substrate 9 and the second electrode 52 is located on the second main surface 92 side, as in the electrode units 5, 5a, 5b of FIG. 3, FIG. 8, FIG. 9, and FIG. 10. In this manner, by disposing the substrate 9 between the first electrode 51 and the second electrode 52, the metal film 96 can be etched efficiently. In the electrode units 5, 5a, 5b, when viewed along a direction perpendicular to the main surfaces 91, 92 of the substrate 9, the first electrode 51 overlaps with the second electrode 52 almost entirely, but the first electrode 51 and the second electrode 52 may only partially overlap. In the substrate processing apparatus 1, when viewed along a direction perpendicular to the main surfaces 91, 92 of the substrate 9, the first electrode 51 and the second electrode 52 at least partially overlap with each other, so that the metal film 96 can be etched efficiently.

[0073] In the above-mentioned substrate processing apparatus 1, the first electrode 51 and the second electrode 52 are arranged at the same or close positions in the circumferential direction, but the first electrode 51 and the second electrode 52 may be provided at a distance from each other. FIG. 11 is a diagram showing a substrate processing apparatus 1a according to a second embodiment. In the substrate processing apparatus 1a, both the first electrode 51 and the second electrode 52 are arranged on the first main surface 91 side of the substrate 9. Specifically, when the electrode unit 5c is arranged at a processing position facing the substrate 9, the first electrode 51 is located near the peripheral portion 93 on the first main surface 91 side. The second electrode 52 is located near the substrate 9, separated from the first electrode 51 in the circumferential direction on the first main surface 91 side. In the example of FIG. 11, the second electrode 52 is also located near the peripheral portion 93.

[0074] The processing liquid filling unit 6 includes a first processing liquid nozzle 61a and a second processing liquid nozzle 61b, both of which are provided on the first main surface 91 side. The first processing liquid nozzle 61a is disposed near the first electrode 51 and ejects the processing liquid L1 toward between the first electrode 51 and the substrate 9. The first electrode 51 is electrically connected to the metal film 96 on the peripheral portion 93 via the processing liquid L1. The second processing liquid nozzle 61b is disposed near the second electrode 52 and ejects the processing liquid L1 toward between the second electrode 52 and the substrate 9. The second electrode 52 is electrically connected to the metal film 96 on the peripheral portion 93 via the processing liquid L1 at a position different from that of the first electrode 51. In this way, the processing liquid filling unit 6 fills the processing liquid L1 between each of the first electrode 51 and the second electrode 52 and the substrate 9, and two different (independent) contact points are provided between the first electrode 51 and the second electrode 52. Furthermore, on the second main surface 92 side of the substrate 9, an auxiliary fluid nozzle 81 is disposed at approximately the same circumferential position as the first electrode 51. The other configuration of the substrate processing apparatus 1a is similar to that shown in FIG.

[0075] In the etching in the substrate processing apparatus 1a, a voltage is applied between the first electrode 51 and the second electrode 52 by the power source 50 while rotating the substrate 9. In the example of FIG. 11, the first electrode 51 is a cathode, and the second electrode 52 is an anode. This causes etching of the metal film 96 on the peripheral portion 93. In addition, the auxiliary fluid nozzle 81 ejects an auxiliary fluid toward the radially outward direction toward the peripheral portion 93. This prevents the processing liquid L1 from spreading radially inward from the peripheral portion 93, even if the processing liquid L1, which is supplied between the first electrode 51 and the substrate 9 and contains the metal removed from the metal film 96, flows around to the second main surface 92 side. As a result, contamination of the second main surface 92 by the processing liquid L1 is suppressed.

[0076] Incidentally, in the substrate processing apparatus 1a as well, the metal film 96 is etched in the vicinity of the first electrode 51, which is a cathode. However, when the etching progresses to a certain extent and the second electrode 52 (anode) faces the area from which the metal film 96 has been removed, the second electrode 52 is no longer electrically connected to the metal film 96. As a result, no current flows between the first electrode 51 and the second electrode 52, and etching does not progress. Also, when the metal film 96 is scattered in the peripheral portion 93, no current flows between the first electrode 51 and the second electrode 52, and etching does not progress.

[0077] In contrast, in the substrate processing apparatus 1 according to the first embodiment, when etching is performed, the first electrode 51 and the second electrode 52 face a target portion, which is a part of the peripheral portion 93 of the substrate 9, and the processing liquid L1 is discharged from the outlet 611 of the processing liquid nozzle 61 (or the outlet 623 of the connection member 622), thereby filling the target portion, the first electrode 51, and the second electrode 52 with the processing liquid L1. As a result, the first electrode 51 and the second electrode 52 are electrically connected to the metal film 96 of the target portion through the same processing liquid L1, that is, substantially at one contact point. As a result, even if there is a region where the metal film 96 has been removed or an isolated metal film 96 exists, it is possible to appropriately etch the metal film 96. Moreover, in the substrate processing apparatus 1 that supplies the processing liquid L1 only to one place on the peripheral portion 93, the consumption of the processing liquid L1 can be significantly reduced.

[0078] The above-mentioned substrate processing apparatus 1, 1a can be modified in various ways.

[0079] In the above embodiment, when the auxiliary fluid nozzle 81 is provided, the auxiliary fluid nozzle 81 is disposed at substantially the same circumferential position as the first electrode 51, but depending on the design of the substrate processing apparatus 1, 1a, for example, the auxiliary fluid nozzle 81 may eject the auxiliary fluid toward the vicinity of the center of the substrate 9 on the second main surface 92 side. In this case, the auxiliary fluid ejected from the auxiliary fluid nozzle 81 flows from the vicinity of the center of the second main surface 92 toward the entire circumference of the peripheral portion 93 (i.e., in all directions toward the peripheral portion 93) due to the rotation of the substrate 9. This makes it possible to prevent the second main surface 92 from being contaminated by the processing liquid L1 containing the metal removed by etching.

[0080] In the substrate processing apparatus 1, the substrate 9 may be held by a substrate holder with the first main surface 91 on which the metal film 96 is formed facing downward. In this case, an electrode facing the first main surface 91 is used as a cathode, and the metal film 96 on the peripheral portion 93 is etched. In addition, the auxiliary fluid nozzle 81 arranged on the side of the second main surface 92 facing upward prevents the processing liquid L1 that has flowed around to the second main surface 92 side from spreading radially inward.

[0081] The substrate holding section that holds the substrate 9 and the rotation mechanism that rotates the substrate 9 may have structures other than the chuck section 21 and the rotation mechanism 22 in Fig. 2. For example, a plurality of rollers may be arranged in the circumferential direction around the substrate 9, and the plurality of rollers may contact the edge end face or the like of the substrate 9 to hold the substrate 9, while some of the rollers rotate on their own axes to rotate the substrate 9 about the central axis J1. Depending on the design of the substrate processing apparatus 1, the electrode units 5, 5a to 5c may rotate about the central axis J1 without rotating the substrate 9. The rotation mechanism in the substrate processing apparatus 1 may be any mechanism that rotates the substrate 9 relatively to the electrode units 5, 5a to 5c.

[0082] The substrates processed in the substrate processing apparatus 1, 1a are not limited to semiconductor substrates, but may be glass substrates or other substrates.

[0083] The configurations in the above-described embodiment and each of the modified examples may be combined as appropriate as long as they are not mutually inconsistent. [Explanation of symbols]

[0084] 1, 1a Substrate processing apparatus 5, 5a~5c Electrode unit 6 Processing liquid filling section 9 Substrate 21 Chuck part 22 Rotation mechanism 50 power supply 51 1st electrode 52 2nd electrode 73 Electrode movement mechanism 81 Auxiliary fluid nozzle 91 (of substrate) first main surface 92 (substrate) second main surface 93 (Circumference of the board) 96 Metal Film 520 Electrode body 522 Lyophilic material 611,623 Discharge port L1 Processing liquid

Claims

1. A substrate processing apparatus that performs etching on a peripheral portion of a substrate, a substrate holder that holds a substrate having a disk shape with a first main surface and a second main surface, the substrate having a metal film provided on a peripheral portion of the substrate on the first main surface side; an electrode unit including a first electrode and a second electrode, the first electrode being located near the peripheral portion on the first main surface side and the second electrode being spaced apart from the first electrode and located near the substrate during etching; a processing liquid filling section that fills a processing liquid between the first electrode and the second electrode and between the substrate and the processing liquid; a power source that applies a voltage between the first electrode and the second electrode to etch a portion of the metal film located near the first electrode; a rotation mechanism that rotates the substrate relative to the electrode unit to move a portion of the peripheral portion to be etched in a circumferential direction; an auxiliary fluid nozzle that ejects an auxiliary fluid toward a radially outward direction relative to the peripheral edge portion on the second main surface side of the substrate when etching is performed; A substrate processing apparatus comprising:

2. The substrate processing apparatus according to claim 1 , The substrate processing apparatus, wherein the auxiliary fluid is a gas.

3. The substrate processing apparatus according to claim 1 , The substrate processing apparatus, wherein the auxiliary fluid is the processing liquid.

4. The substrate processing apparatus according to claim 1 , When performing etching, the first electrode and the second electrode face a target portion that is a part of the peripheral portion of the substrate, The substrate processing apparatus, wherein the processing liquid filling section discharges the processing liquid from a discharge port to form a liquid filled state in which the processing liquid fills a space between the target portion, the first electrode, and the second electrode.

5. The substrate processing apparatus according to claim 4, An electrode moving mechanism for moving the electrode unit is further provided. The electrode moving mechanism moves a member having the discharge port in the processing liquid filling section and the auxiliary fluid nozzle together with the electrode unit.

6. A substrate processing apparatus that performs etching on a peripheral portion of a substrate, a substrate holder configured to hold, in a horizontal position, a substrate having a disk shape with a first main surface and a second main surface, the substrate having a metal film provided on a peripheral portion of the first main surface; an electrode unit having a first electrode and a second electrode, the first electrode being located in the vicinity of a target portion that is a part of the peripheral portion on the first main surface side facing upward, and the second electrode being opposed to the target portion on the second main surface side facing downward, during etching; a treatment liquid filling section that discharges a treatment liquid from a discharge port to form a liquid filled state in which the treatment liquid is filled between the target site, the first electrode, and the second electrode; a power source that applies a voltage between the first electrode and the second electrode to etch the metal film on the target portion; a rotation mechanism that rotates the substrate relative to the electrode unit to move the target site in the peripheral portion in a circumferential direction; Equipped with The substrate processing apparatus includes a side surface of the second electrode that includes a region that is lyophilic with respect to the processing liquid.

7. 7. The substrate processing apparatus according to claim 6, The second electrode is An electrode body; a liquid-philic member covering at least a radially inner region of a side surface of the electrode body; Equipped with The substrate processing apparatus, wherein the lyophilic area is a surface of the lyophilic member.

8. 8. The substrate processing apparatus according to claim 4, The substrate processing apparatus, wherein the first electrode and the second electrode at least partially overlap when viewed along a direction perpendicular to a main surface of the substrate.

Images