Substrate processing method and substrate processing apparatus

Abstract

A substrate processing method for processing a substrate having a main surface including a recess-forming surface forming a recess and a removed layer formed in the recess. The substrate processing method includes: an etching step of supplying an etching liquid containing etching ions to the main surface of the substrate to etch the removed layer; a concentration step of concentrating the etching liquid on the main surface of the substrate; a hydrophilization step of hydrophilizing the recess-forming surface exposed by the concentration of the etching liquid; an ion diffusion step of diffusing the etching ions into a rinse liquid by supplying the rinse liquid to the main surface of the substrate after the hydrophilization step; and a rinse liquid removal step of removing the rinse liquid from the main surface of the substrate.

Description

Technical Field

[0001] This invention relates to a substrate processing method and an apparatus for processing substrates.

[0002] The substrates that are processed include, for example, substrates for FPD (Flat Panel Display) such as semiconductor wafers, liquid crystal display devices and organic EL (Electroluminescence) display devices, substrates for optical discs, substrates for magnetic disks, substrates for optical disks, substrates for photomasks, ceramic substrates, substrates for solar cells, etc. Background Technology

[0003] The shapes of patterns formed by etching are diverse. With the miniaturization of patterns or the three-dimensional construction of electronic components, it is required to form narrow-aperture recesses through etching.

[0004] Therefore, Patent Document 1 below discloses a technique for hydrophilizing the surface of a recess in order to facilitate the entry of the etching solution into the narrow opening of the recess.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-155612 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] The movement of the etching solution is restricted in narrow spaces. Therefore, in Patent Document 1, there is a concern that the etching solution entering the narrow recess of the opening may not be adequately removed from the recess.

[0010] Therefore, one object of the present invention is to provide a substrate processing method and a substrate processing apparatus that, in a configuration for etching a removed layer formed in a recess on the main surface of a substrate, can suppress the presence of etching solution residue in the recess.

[0011] means for solving problems

[0012] An embodiment of the present invention provides a substrate processing method for processing a substrate having a main surface including a recess forming surface, and a layer to be removed is formed in the recess.

[0013] The substrate processing method includes: an etching step in which an etching solution containing etching ions is supplied to the main surface of the substrate to etch the layer to be removed; a concentration step in which the etching solution on the main surface of the substrate is concentrated; a hydrophilization step in which the recessed surface exposed by the concentration of the etching solution is hydrophilized; an ion diffusion step in which, after the hydrophilization step, the etching ions are diffused into the rinsing solution by supplying a rinsing solution to the main surface of the substrate; and a rinsing solution removal step in which the rinsing solution is removed from the main surface of the substrate.

[0014] According to this substrate processing method, after the metal layer and other layers to be removed are removed by the etching solution, the etching solution is concentrated. Therefore, the etching solution remains within the recess, while the recess formation surface is exposed. Thus, through a subsequent hydrophilization step, the recess formation surface can be effectively hydrophilized.

[0015] After the recessed surface is hydrophilized, a rinsing solution is supplied to the main surface of the substrate, allowing the rinsing solution to easily enter the recess. Since the rinsing solution entering the recess comes into contact with the concentrated etchant, a difference in ion concentration (ion concentration gradient) is generated. Specifically, the etchant with an increased etchant ion concentration due to concentration comes into contact with the rinsing solution, which contains no etchant ions. Therefore, to homogenize the etchant ion concentration, etchant ions diffuse into the rinsing solution. This causes the etchant ions to move out of the recess, suppressing the retention of etchant within the recess. Subsequently, by removing the rinsing solution from the main surface of the substrate, etchant ions can be removed from the main surface of the substrate. Therefore, the situation where the rinsing solution is concentrated and etchant ions remain in the recess can be prevented.

[0016] In one embodiment of the present invention, the width of the recess is 5 nm or less. This restricts the movement of the rinsing solution into the recess. Therefore, if the recess formation surface is made hydrophilic after the etching solution is concentrated, the entry of the rinsing solution into the recess can be promoted.

[0017] In one embodiment of the present invention, after the above-described rinsing solution removal step, the above-described ion diffusion step and the above-described rinsing solution removal step are each repeated at least once. According to this method, even if there are cases where diffusion using the rinsing solution alone is insufficient to fully remove the etch ions remaining in the recess, by performing diffusion using the rinsing solution multiple times, the etch ions remaining in the recess can be fully removed.

[0018] In one embodiment of the present invention, the hydrophilization step includes an oxidation step of oxidizing the recessed surface.

[0019] In one embodiment of the present invention, the oxidation step includes a liquid oxidant supply step of supplying a liquid oxidant to the main surface of the substrate. According to this method, the hydrophilization of the recessed surface, performed between the supply of the etching solution and the supply of the rinsing solution, is achieved by the supply of the liquid oxidant, i.e., the liquid. Therefore, unlike the case where the recessed surface is hydrophilized by the supply of a gaseous oxidant or by ultraviolet irradiation, it is not necessary to move the substrate to another chamber for hydrophilization. Therefore, substrate processing can be performed quickly.

[0020] In one embodiment of the present invention, the substrate processing method further includes an oxidant removal step, which removes the liquid oxidant supplied to the main surface of the substrate from the main surface of the substrate before the ion diffusion step.

[0021] According to this method, liquid oxidant is removed from the main surface of the substrate before the rinsing solution is supplied to it. Therefore, the increase in ion concentration in the rinsing solution due to the introduction of oxidant into the rinsing solution supplied to the main surface of the substrate can be suppressed. Consequently, the decrease in ion concentration gradient caused by contact between the concentrated etchant and the rinsing solution can be suppressed. As a result, etchant residue within the recesses can be suppressed.

[0022] In one embodiment of the present invention, the oxidation step includes at least one of a dry oxidation step: supplying a gaseous oxidant to the main surface of the substrate and irradiating the main surface of the substrate with light. According to this method, the recessed surface can be hydrophilized without the use of liquid. Therefore, it is possible to prevent the liquid used for substrate hydrophilization from mixing into the rinsing solution and causing an increase in the ion concentration in the rinsing solution.

[0023] In one embodiment of the present invention, the above-mentioned concentration step includes a drying step of drying the main surface of the above-mentioned substrate.

[0024] In one embodiment of the present invention, the etching step includes an etching solution supply step of spraying the etching solution from an etching solution nozzle toward the main surface of the substrate held by the substrate holding member, thereby supplying the etching solution to the main surface of the substrate. Furthermore, the drying step includes a rotary evaporation step of rotating the substrate by rotating the substrate holding member around a rotation axis passing through the center of the main surface of the substrate and orthogonal to the main surface of the substrate, thereby causing the solvent components contained in the etching solution to evaporate from the main surface of the substrate.

[0025] The supply of etching solution to the main surface of the substrate, and the evaporation of the solvent components of the etching solution from the main surface of the substrate, are both performed while the substrate is held by a substrate holding member. Therefore, the etching solution can be quickly concentrated after etching is completed.

[0026] In one embodiment of the present invention, the drying step includes a depressurization evaporation step, in which the solvent components contained in the etching solution are evaporated from the main surface of the substrate by depressurizing the space in contact with the main surface of the substrate. According to this method, the etching solution can be rapidly concentrated by depressurizing the space in contact with the main surface of the substrate.

[0027] In another embodiment of the present invention, a substrate processing apparatus is provided for processing a substrate having a main surface including a recess forming surface, and a layer to be removed being formed within the recess. The substrate processing apparatus includes: an etching solution supply member for supplying an etching solution containing etching ions and etching the layer to be removed to the main surface of the substrate; an etching solution concentration member for concentrating the etching solution on the main surface of the substrate; a hydrophilization member for hydrophilizing the recess forming surface exposed by the concentration of the etching solution; a rinsing solution supply member for supplying a rinsing solution that diffuses the etching ions into a liquid to the main surface of the substrate; and a rinsing solution removal member for removing the rinsing solution from the main surface of the substrate. According to this substrate processing apparatus, the same effects as the substrate processing method described above can be achieved.

[0028] The above, or other, objects, features, and effects of the present invention will be further explained with reference to the accompanying drawings and the following description of the embodiments. Attached Figure Description

[0029] Figure 1A This is a schematic cross-sectional view used to illustrate the structure of the surface layer of the device side of the substrate to be processed.

[0030] Figure 1B From Figure 1A The diagram shown by arrow IB.

[0031] Figure 2A This is a top view for illustrating the configuration of the substrate processing apparatus according to the first embodiment of the present invention.

[0032] Figure 2B This is a front view used to illustrate the configuration of the above-described substrate processing apparatus.

[0033] Figure 3 This is a cross-sectional view illustrating an example of the configuration of the wet processing unit included in the aforementioned substrate processing apparatus.

[0034] Figure 4 This is a block diagram illustrating an example of the configuration of the control of the aforementioned substrate processing apparatus.

[0035] Figure 5 This is a flowchart illustrating an example of substrate processing performed by the aforementioned substrate processing apparatus.

[0036] Figure 6AThis is a schematic diagram illustrating the substrate condition during the aforementioned substrate processing.

[0037] Figure 6B This is a schematic diagram illustrating the substrate condition during the aforementioned substrate processing.

[0038] Figure 6C This is a schematic diagram illustrating the substrate condition during the aforementioned substrate processing.

[0039] Figure 6D This is a schematic diagram illustrating the substrate condition during the aforementioned substrate processing.

[0040] Figure 7 This is a schematic diagram used to illustrate the situation near the upper surface of the substrate during the above substrate processing.

[0041] Figure 8 A flowchart illustrating other examples of the above-described substrate processing.

[0042] Figure 9 This is a top view for illustrating the configuration of the substrate processing apparatus according to the second embodiment of the present invention.

[0043] Figure 10 This is a schematic cross-sectional view of the gas oxidation processing unit included in the substrate processing apparatus of the second embodiment for explaining the invention.

[0044] Figure 11 This is a flowchart illustrating an example of substrate processing performed by the substrate processing apparatus of the second embodiment.

[0045] Figure 12 This is a schematic diagram illustrating the situation near the upper surface of the substrate during substrate processing in the second embodiment.

[0046] Figure 13 This is a schematic cross-sectional view illustrating an example of the configuration of the light irradiation processing unit included in the substrate processing apparatus of the second embodiment.

[0047] Figure 14 A flowchart illustrating another example of substrate processing performed by the substrate processing apparatus of the second embodiment. Detailed Implementation

[0048] <Structure of the surface layer of the substrate to be processed>

[0049] Figure 1A This is a schematic cross-sectional view used to illustrate the structure of the surface layer of the device surface of the substrate W, which is the object of processing. Figure 1B From Figure 1AThe diagram shown is viewed by arrow IB. The substrate W is a substrate such as a silicon wafer and has a pair of main surfaces. At least one of the main surfaces is a device surface with a raised / lowered pattern formed on it. One of the main surfaces may be a non-device surface without a raised / lowered pattern, or both main surfaces may be device surfaces with different raised / lowered patterns formed on each other.

[0050] On the surface portion of at least one device surface, a structure 102 having a plurality of recesses 100 is formed, for example, and a plurality of metal layers 103 respectively embedded in the plurality of recesses 100. The structure 102 may be, for example, an insulating layer such as silicon oxide (SiO2), a semiconductor layer such as polysilicon, or a combination thereof. The metal layer 103 may be, for example, titanium nitride. The metal layer 103 is an example of a layer to be removed, but the layer to be removed is not limited to a metal layer.

[0051] The structure 102 has a plurality of recess forming surfaces 104 that respectively form a plurality of recesses 100. The recess forming surfaces 104 constitute part of the main surface of the substrate W. The recess forming surfaces 104 have: a bottom surface 104a forming the bottom of the recess 100 and a side surface 104b forming the opening of the recess 100.

[0052] When viewed from the depth direction D of the recess 100, for example, it is a quadrangular shape, with the width W1 of the short side of the recess 100 being 1 nm or more and 5 nm or less, and the width W2 of the long side of the recess 100 being 10 nm or more and 50 nm or less. Unlike... Figure 1B When viewed from the depth direction D, the recess 100 can also be circular. In this case, the diameter (width) of the recess 100 is more than 1 nm and less than 5 nm.

[0053] <Configuration of the substrate processing apparatus in the first embodiment>

[0054] Figure 2A This is a top view for illustrating the configuration of the substrate processing apparatus 1 according to the first embodiment of the present invention. Figure 2B This is a front view used to illustrate the configuration of the substrate processing apparatus 1.

[0055] The substrate processing apparatus 1 is a monolithic device that processes substrates W one by one. In this embodiment, the substrate W is in the shape of a disc. In this embodiment, the substrate W is processed with the device surface on which the structure 102 is formed is facing upward.

[0056] The substrate processing apparatus 1 includes: multiple processing units 2 for processing substrates W; a loading port LP for holding a conveyor CA for accommodating multiple substrates W processed by the processing units 2; a transport robot IR and CR for transporting substrates W between the loading port LP and the processing units 2; and a controller 3 for controlling the substrate processing apparatus 1.

[0057] The transfer robot IR transfers substrate W between the conveyor CA and the transfer robot CR. The transfer robot CR transfers substrate W between the transfer robot IR and the processing unit 2.

[0058] Each conveying robot IR and CR is, for example, a multi-joint arm robot consisting of a pair of multi-joint arms AR and a pair of hands H respectively located at the top of the pair of multi-joint arms AR in a way that is separated from each other vertically.

[0059] Multiple processing units 2 form four processing towers respectively arranged in four horizontally separated positions. Each processing tower contains multiple (three in this embodiment) processing units 2 stacked vertically (see reference). Figure 2B Two processing towers are configured on each side of the conveying path TR extending from the loading port LP towards the conveying robots IR and CR (see reference). Figure 2A ).

[0060] In the first embodiment, the processing unit 2 is a wet processing unit 2W that processes the substrate W using a liquid. Each wet processing unit 2W includes: a chamber 4; and a processing cup 7 disposed within the chamber 4. The processing of the substrate W is performed within the processing cup 7.

[0061] Chamber 4 has an entrance / exit (not shown) for moving substrate W into or out by a transport robot CR. Chamber 4 is equipped with a gate unit (not shown) for opening and closing the entrance / exit.

[0062] Figure 3 This is a schematic cross-sectional view illustrating an example of the configuration of the wet treatment unit 2W.

[0063] The wet processing unit 2W further includes: a rotary chuck 5 that holds the substrate W in a predetermined first holding position while rotating the substrate W about a rotation axis A1 (vertical axis); and a counter-member 6 that faces the substrate W held in the rotary chuck 5 from above. The rotation axis A1 passes through the center of the substrate W and is orthogonal to the main surface of the substrate W. That is, the rotation axis A1 extends vertically. The first holding position is... Figure 3 The position of the substrate W shown is the position of the substrate W held in a horizontal posture.

[0064] The rotary chuck 5 includes: a rotating base 21 having a circular plate shape along the horizontal direction; a plurality of chuck pins 20 holding the substrate W above the rotating base 21 and holding the substrate W in a first holding position; a rotating shaft 22 connected at its upper end to the rotating base 21 and extending in the vertical direction; and a rotation drive member 23 for rotating the rotating shaft 22 about its central axis (rotation axis A1). The rotary chuck 5 is an example of a substrate holding member.

[0065] Multiple chuck pins 20 are spaced apart on the upper surface of the rotating base 21 in the circumferential direction. The rotation drive member 23 is, for example, an actuator such as an electric motor. The rotation drive member 23 rotates the rotating base 21 and the multiple chuck pins 20 about the rotation axis A1 by rotating the rotation shaft 22. As a result, the substrate W rotates together with the rotating base 21 and the multiple chuck pins 20 about the rotation axis A1.

[0066] Multiple chuck pins 20 are movable between a closed position, in contact with the periphery of the substrate W and holding the substrate W, and an open position, retracting from the periphery of the substrate W. The multiple chuck pins 20 are moved by a switching mechanism (not shown). When the multiple chuck pins 20 are in the closed position, they hold the periphery of the substrate W horizontally. The switching mechanism includes, for example, a linkage mechanism and an actuator that applies a driving force to the linkage mechanism.

[0067] The opposing member 6 is a plate-shaped member that blocks the ambient gas in the space between itself and the upper surface of the substrate W held in the rotating chuck 5 from the ambient gas outside the space. Therefore, the opposing member 6 is also called a blocking plate.

[0068] The opposing member 6 has an opposing surface 6a that faces the upper surface of the substrate W held in the rotating chuck 5 from above. The opposing member 6 is formed into a circular plate with a diameter that is almost the same as or greater than that of the substrate W. In the opposing member 6, a support shaft 33 is fixed on the side opposite to the opposing surface 6a.

[0069] The opposing member 6 is connected to an opposing member lifting mechanism 34 that raises and lowers the opposing member 6. The opposing member lifting mechanism 34 may have, for example, an electric motor or cylinder that drives the support shaft 33 to rise and fall, or other actuators. The opposing member 6 may also rotate about the rotation axis A1.

[0070] The processing cup 7 collects liquid that splashes from the substrate W held in the rotating chuck 5. The processing cup 7 comprises multiple containers for collecting liquid that splashes outward from the substrate W held in the rotating chuck 5. Figure 3 (In the example, there are two) baffles 30; multiple ( ) baffles 30 to receive the liquid guided downwards by the multiple baffles 30 Figure 3 (Two cups in the example) 31; a cylindrical outer wall member 32 surrounding the plurality of baffles 30 and the plurality of cups 31. The plurality of baffles 30 are individually raised and lowered by a baffle raising and lowering drive mechanism (not shown). The baffle raising and lowering drive mechanism may, for example, have an electric motor or cylinder for raising and lowering each baffle 30, or may have other actuators.

[0071] The wet processing unit 2W also includes: an etching solution nozzle 10 for supplying etching solution to the upper surface (upper main surface) of the substrate W held in the rotary chuck 5; a liquid oxidant nozzle 11 for supplying liquid oxidant to the upper surface of the substrate W held in the rotary chuck 5; and a rinsing solution nozzle 12 for supplying rinsing solution to the upper surface of the substrate W held in the rotary chuck 5.

[0072] The etching solution, such as hydrofluoric acid or APM solution (ammonia-hydrogen peroxide water mixture), is a liquid containing etching ions that etches the metal layer 103. Etching ions, for example, are HF2. - NH4 + The components used to oxidize and remove metal layer 103 are as follows: In the case of hydrofluoric acid as the etching solution, the etchant ions are HF2. - When the etching solution is APM solution, the etchant ions are NH4+. + The solvent component of the etching solution may be, for example, water. The etching solution may also contain migration promoters such as ammonium chloride, which promote the movement of etching ions within the recess 100.

[0073] The liquid oxidant is an example of a hydrophilic liquid used to hydrophilize the main surface of substrate W. For example, the liquid oxidant is a liquid oxidant that hydrophilizes the main surface of substrate W by oxidizing it. Examples of liquid oxidants include APM solution, hydrogen peroxide solution, ozone solution, or mixtures thereof. The liquid oxidant contains hydrogen peroxide, ozone, etc., as oxidants.

[0074] The rinsing solution is preferably composed primarily of the same solvent components (e.g., water) as the etching solution. Examples of rinsing solutions include at least one of deionized water (DIW), carbonated water, electrolyzed water, hydrochloric acid at a dilution concentration (e.g., 1 ppm to 100 ppm), ammonia at a dilution concentration (e.g., 1 ppm to 100 ppm), and reduced water (hydrogen water). More preferably, the rinsing solution does not contain electrolytes, and more preferably, DIW is used as the rinsing solution.

[0075] Both the etchant nozzle 10 and the liquid oxidant nozzle 11 are movable nozzles that can move at least in the horizontal direction. The etchant nozzle 10 and the liquid oxidant nozzle 11 are moved in the horizontal direction by multiple nozzle moving mechanisms (a first nozzle moving mechanism 35 and a second nozzle moving mechanism 36). Each nozzle moving mechanism includes: an arm (not shown) supporting the corresponding nozzle; and an arm moving mechanism (not shown) for moving the corresponding arm in the horizontal direction. Each arm moving mechanism may have an electric motor or a cylinder, or other actuators. Alternatively, the etchant nozzle 10 and the liquid oxidant nozzle 11 may be configured to move integrally via a common nozzle moving mechanism.

[0076] The etching solution nozzle 10 and the liquid oxidant nozzle 11 can also be configured to move in the vertical direction.

[0077] In this embodiment, the rinsing fluid nozzle 12 is a fixed nozzle whose horizontal and vertical positions are fixed, but it can also be a movable nozzle like the etching fluid nozzle 10 and the liquid oxidant nozzle 11.

[0078] The etching solution nozzle 10 is connected to one end of the etching solution pipe 40 that guides the etching solution to the nozzle 10. The other end of the etching solution pipe 40 is connected to the etching solution tank (not shown). The etching solution pipe 40 is equipped with an etching solution valve 50A that switches the flow path within the pipe 40, and an etching solution flow rate regulating valve 50B that adjusts the flow rate of the etching solution within the flow path.

[0079] When the etching solution valve 50A is opened, the etching solution is continuously ejected downwards from the nozzle of the etching solution nozzle 10 at a flow rate corresponding to the opening of the etching solution flow rate regulating valve 50B. The etching solution nozzle 10 is an example of an etching solution supply component.

[0080] A liquid oxidant nozzle 11 is connected to one end of a liquid oxidant pipe 41 that guides the liquid oxidant to the nozzle. The other end of the liquid oxidant pipe 41 is connected to a liquid oxidant tank (not shown). A liquid oxidant valve 51A for opening and closing the flow path within the liquid oxidant pipe 41, and a liquid oxidant flow regulating valve 51B for adjusting the flow rate of the liquid oxidant within the flow path are installed in the liquid oxidant pipe 41.

[0081] When the liquid oxidant valve 51A is opened, the liquid oxidant is continuously ejected downwards from the outlet of the liquid oxidant nozzle 11 at a flow rate corresponding to the opening of the liquid oxidant flow regulating valve 51B. The liquid oxidant nozzle 11 is an example of a liquid oxidant supply component.

[0082] The flushing fluid nozzle 12 is connected to one end of the flushing fluid pipe 42 that guides the flushing fluid to the flushing fluid nozzle 12. The other end of the flushing fluid pipe 42 is connected to the flushing fluid tank (not shown). The flushing fluid pipe 42 is equipped with a flushing fluid valve 52A that opens and closes the flow path within the flushing fluid pipe 42, and a flushing fluid flow rate regulating valve 52B that adjusts the flow rate of the flushing fluid in the flow path.

[0083] When the flushing fluid valve 52A is opened, the flushing fluid is continuously ejected from the nozzle 12 at a flow rate corresponding to the opening of the flushing fluid flow rate regulating valve 52B. The flushing fluid nozzle 12 is an example of a flushing fluid supply component.

[0084] Figure 4 This is a block diagram illustrating an example of the configuration of the control of the substrate processing apparatus 1.

[0085] The controller 3 is equipped with a microcomputer and controls the controlled objects of the substrate processing apparatus 1 according to a prescribed control program. Specifically, the controller 3 includes a processor (CPU) 3A and a memory 3B for storing programs, and is configured to execute various control processes for substrate processing by executing programs through the processor 3A.

[0086] In particular, controller 3 is programmed to control the various components (valve, motor, etc.) constituting the wet processing unit 2W, the conveying robots IR and CR, etc. Controller 3 also similarly controls the components (valve, motor, power supply, etc.) constituting the dry processing unit 2D, which will be described later.

[0087] The controller 3 controls whether fluid is ejected from the corresponding nozzle, or the flow rate of fluid ejected from the corresponding nozzle, by controlling the valve. The following steps are executed by the controller 3 controlling these components. In other words, the controller 3 is programmed to execute the following steps.

[0088] <An example of substrate processing>

[0089] Figure 5 This is a flowchart illustrating an example of substrate processing performed by substrate processing apparatus 1. Figure 5 This mainly refers to the processing implemented by the program executed by controller 3. Figures 6A to 6D This is a schematic diagram illustrating the steps of substrate processing performed by substrate processing apparatus 1.

[0090] In the substrate processing performed by the substrate processing apparatus 1, for example, Figure 5 As shown, the following steps are performed in sequence: substrate loading (step S1), etching solution supply (step S2), etching solution removal (step S3), liquid oxidant supply (step S4), oxidant removal (step S5), rinsing solution supply (step S6), rinsing solution removal (step S7), and substrate unloading (step S8).

[0091] The following refers primarily to the substrate processing performed by the substrate processing apparatus 1. Figure 3 and Figure 5 Please provide an explanation. (References may vary.) Figures 6A to 6D .

[0092] First, the untreated substrate W is transported by the robotic arms IR and CR (refer to...). Figure 2AThe substrate W is transferred from the conveyor CA to the wet processing unit 2W and then to the rotary chuck 5 (substrate loading step: step S1). The substrate W is then held horizontally by the rotary chuck 5 (substrate holding step). The holding of the substrate W by the rotary chuck 5 continues until the rinsing liquid removal step (step S7) ends. When the substrate W is loaded into the wet processing unit 2W, the opposing member 6 is positioned such that the nozzle can pass through the gap between the substrate W and the opposing member 6. Figure 3 (The position of the opposing member 6 is shown). With the substrate W held in place by the rotary chuck 5, the rotation drive member 23 begins to rotate the substrate W (substrate rotation step).

[0093] Next, after the transport robot CR retreats to outside the processing unit 2, it performs the etching solution supply step (step S2) of supplying etching solution to the upper surface of the substrate W.

[0094] Specifically, the first nozzle moving mechanism 35 moves the etching solution nozzle 10 to the processing position, and while the etching solution nozzle 10 is in the processing position, the etching solution valve 50A is opened. Thus, as... Figure 6A As shown, etching solution is ejected from etching solution nozzle 10 toward the upper surface of substrate W (etching solution ejection step). The etching solution ejected from etching solution nozzle 10 falls onto the upper surface of substrate W. The etching solution is spread to the entire upper surface of substrate W by centrifugal force, and is supplied to the entire upper surface of substrate W (etching solution supply step).

[0095] In this substrate processing, the etching nozzle 10 is positioned at the center of the upper surface of the substrate W, opposite to the outlet of the etching nozzle 10. Therefore, the etching solution will fall onto the central region of the upper surface of the substrate W. In a different substrate processing method, the etching nozzle 10 can also spray etching solution while moving horizontally along the upper surface of the substrate W.

[0096] The etching solution is ejected at a specified flow rate and continuously for a specified ejection period. The ejection period is, for example, 5 seconds or more and 180 seconds or less. The ejection flow rate is, for example, 500 mL / min or more and 2000 mL / min or less. During the ejection of the etching solution, the substrate W rotates at, for example, a rotation speed of 300 rpm or more and 1200 rpm or less.

[0097] After the etch solution supply step, an etch solution removal step (step S3) is performed to remove the etch solution from the upper surface of the substrate W.

[0098] Specifically, the etching solution valve 50A is closed to stop the ejection of the etching solution, and the rotation of the substrate W is accelerated by the rotation drive member 23, causing the substrate W to rotate at high speed. In the etching solution removal step, the substrate W rotates at a speed of, for example, 1500 rpm or more and 2500 rpm or less, for a period of, for example, 60 seconds or more and 180 seconds or less. By rotating the substrate W at high speed, the etching solution is thrown off from the upper surface of the substrate W, and most of the etching solution is discharged outside the substrate W, and the solvent component in the etching solution evaporates from the upper surface of the substrate W (first rotation discharge step, first rotation evaporation step). As a result, the etching solution is removed from the upper surface of the substrate W, and the upper surface of the substrate W is dried (first drying step).

[0099] However, as detailed later, the etching solution was not completely removed from the upper surface of the substrate W and remained in the recess 100 until the end of the rinsing solution removal step (step S7) described later.

[0100] The evaporation of solvent components caused by the rotation of substrate W is explained in detail. The centrifugal force of substrate W during high-speed rotation acts not only on the liquid on the upper surface of substrate W, but also on the ambient gas in contact with the upper surface of substrate W. Therefore, as... Figure 6B As shown, due to the centrifugal force of the substrate W, an airflow F is formed in the space SP1, which is in contact with the etching solution on the substrate W, from the center side to the periphery side of the upper surface of the substrate W. Through this airflow F, the gaseous solvent in contact with the etching solution on the substrate W is expelled from the substrate W. Therefore, the evaporation of the solvent components in the etching solution is promoted (first rotary evaporation step).

[0101] In the etching solution removal step, such as Figure 6B As shown, the opposing member 6 is positioned in a depressurization position closer to the upper surface of the substrate W than in the departure position. With the opposing member 6 in the depressurization position, the substrate W is rotated at high speed to generate an airflow F, which depressurizes the space SP1 between the opposing member 6 and the substrate W. This promotes the evaporation of solvent components in the etching solution (first depressurization evaporation step).

[0102] After the ejection of the etching solution stops, the etching solution nozzle 10 moves to a retracted position via the first nozzle moving mechanism 35. The retracted position of the etching solution nozzle 10 is a position where it is not facing the upper surface of the substrate W and is located outside the processing cup 7 when viewed from above.

[0103] After the etching solution removal step, a liquid oxidant supply step (step S4) is performed to supply liquid oxidant to the upper surface of the substrate W.

[0104] Specifically, the opposing member 6 is positioned in the departing position by the opposing member lifting mechanism 34. With the opposing member 6 in the departing position, the liquid oxidant nozzle 11 is moved to the processing position by the second nozzle moving mechanism 36. Then, with the liquid oxidant nozzle 11 in the processing position, the liquid oxidant valve 51A is opened. Thus, as... Figure 6C As shown, liquid oxidant is sprayed from the liquid oxidant nozzle 11 onto the upper surface of the substrate W (liquid oxidant spraying step). The liquid oxidant sprayed from the liquid oxidant nozzle 11 falls onto the upper surface of the substrate W. The liquid oxidant spreads to the entire upper surface of the substrate W by centrifugal force, and is supplied to the entire upper surface of the substrate W (liquid oxidant supply step).

[0105] In this substrate processing, the liquid oxidant nozzle 11 is positioned at the center of the upper surface of the substrate W, opposite to the central region of the nozzle outlet. Therefore, the liquid oxidant will land in the central region of the upper surface of the substrate W. Alternatively, the liquid oxidant nozzle 11 can also spray liquid oxidant while moving horizontally along the upper surface of the substrate W.

[0106] The liquid oxidant is ejected at a specified flow rate and continuously for a specified ejection period. The ejection period is, for example, 5 seconds or more and 180 seconds or less. The flow rate is, for example, 500 mL / min or more and 2000 mL / min or less. During the ejection of the liquid oxidant, the substrate W rotates at, for example, a rotation speed of 300 rpm or more and 1200 rpm or less.

[0107] After the liquid oxidant supply step, a liquid oxidant removal step (step S5) is performed to remove the liquid oxidant from the upper surface of the substrate W.

[0108] Specifically, the liquid oxidant valve 51A is closed to stop the ejection of liquid oxidant, and the rotation of the substrate W is accelerated by the rotation drive member 23, causing the substrate W to rotate at high speed. In the liquid oxidant removal step, the substrate W rotates at a speed of, for example, 1500 rpm or more and 2500 rpm or less, for a period of, for example, 60 seconds or more and 180 seconds or less. By rotating the substrate W at high speed, the liquid oxidant is thrown off from the upper surface of the substrate W, and most of the liquid oxidant is discharged outside the substrate W, causing the liquid oxidant to evaporate from the upper surface of the substrate W (second rotation discharge step, second rotation evaporation step). As a result, the liquid oxidant is removed from the upper surface of the substrate W, and the upper surface of the substrate W is dried (second drying step).

[0109] In the oxidant removal step, similarly to the liquid oxidant supply step, the evaporation of the liquid oxidant is promoted by the airflow F formed by the centrifugal force generated during the high-speed rotation of the substrate W. Furthermore, in the oxidant removal step, as in... Figure 6B As shown, the opposing member 6 can also be positioned in the depressurization position (second depressurization evaporation step).

[0110] After the supply of liquid oxidant is stopped, the liquid oxidant nozzle 11 is moved to a retracted position by the second nozzle moving mechanism 36. The retracted position of the liquid oxidant nozzle 11 is a position that is not opposite to the upper surface of the substrate W and is located outside the processing cup 7 when viewed from above.

[0111] After removing the liquid oxidant from the upper surface of the substrate W, a rinsing solution supply step (step S6) is performed to supply rinsing solution to the upper surface of the substrate W.

[0112] Specifically, the opposing member 6 is positioned in the disengaged position by the opposing member lifting mechanism 34. With the opposing member 6 in the disengaged position, the flushing fluid valve 52A is opened. Thus, as... Figure 6D As shown, rinsing fluid is sprayed from the rinsing fluid nozzle 12 toward the upper surface of the substrate W (rinsing fluid spraying step). The rinsing fluid sprayed from the rinsing fluid nozzle 12 falls onto the upper surface of the substrate W. The rinsing fluid is spread to the entire upper surface of the substrate W by centrifugal force, and is supplied to the entire upper surface of the substrate W (rinsing fluid supply step).

[0113] The rinsing fluid is sprayed at a specified flow rate and continuously for a specified spraying period. The spraying period is, for example, 10 seconds or more and 180 seconds or less. The spraying flow rate is, for example, 500 mL / min or more and 2000 mL / min or less. During the spraying of the rinsing fluid, the substrate W is rotated at, for example, a rotation speed of 300 rpm or more and 1200 rpm or less.

[0114] After the rinsing fluid supply step, a rinsing fluid removal step (step S7) is performed to remove the rinsing fluid from the upper surface of the substrate W.

[0115] Specifically, the flushing fluid valve 52A is closed to stop the flushing fluid from being ejected, and the rotation of the substrate W is accelerated by the rotation drive member 23, causing the substrate W to rotate at high speed. In the flushing fluid removal step, the substrate W rotates at a speed of, for example, 1500 rpm or more and 2500 rpm or less, for a period of, for example, 60 seconds or more and 180 seconds or less. By rotating the substrate W at high speed, the flushing fluid is thrown off from the upper surface of the substrate W, and most of the flushing fluid is discharged outside the substrate W, and the solvent component in the flushing fluid evaporates from the upper surface of the substrate W (third rotation discharge step, third rotation evaporation step). As a result, the flushing fluid is removed from the upper surface of the substrate W, and the upper surface of the substrate W is dried (third drying step).

[0116] In the rinsing solution removal step, similarly to the etching solution removal step, the evaporation of the rinsing solution is promoted by the airflow F formed by the centrifugal force generated during the high-speed rotation of the substrate W. Furthermore, in the rinsing solution removal step, as... Figure 6B As shown, the opposing member 6 can also be positioned in the depressurization position (third depressurization evaporation step).

[0117] After the rinsing fluid removal step (step S7), the opposing member 6 is moved to the departure position by the opposing member lifting mechanism 34, and the rotation of the substrate W is stopped by the rotation drive member 23. Then, the transfer robot CR enters the wet processing unit 2W, picks up the processed substrate W from the rotary chuck 5, and removes it from the wet processing unit 2W (substrate removal step: step S8). This substrate W is transferred from the transfer robot CR to the transfer robot IR, and is stored in the conveyor CA by the transfer robot IR.

[0118] Figure 7 This is a schematic diagram illustrating the situation near the upper surface of substrate W during substrate processing.

[0119] Etching solution is supplied to the upper surface of the substrate W in the etching solution supply step (step S2), such as... Figure 7 As shown in (a), the metal layer 103 within the recess 100 is removed (etching step). At the end of the etching solution supply step, it is preferable to... Figure 7 As shown in (b), the metal layer 103 inside the recess 100 is completely removed.

[0120] Subsequently, in the etchant removal step (step S3), the etchant 110 is discharged outside the substrate W, and the solvent components in the etchant 110 are evaporated. Therefore, the etchant is concentrated, as... Figure 7 As shown in (c), the concentrated etching solution 110 remains in the recess 100 (concentration step).

[0121] If the width W1 of the recess 100 on the main surface of the substrate W is less than 5 nm, the recess 100 is very narrow. Therefore, due to the evaporation of the solvent components, the concentration of etch ions 111 in the etchant 110 increases, and the vapor pressure of the solvent decreases. Furthermore, in such a narrow area as the recess 100, the vapor pressure of the solvent decreases. Therefore, even during the etchant removal step, the etchant 110 is not completely removed and easily remains at the bottom of the recess 100.

[0122] Due to the evaporation of the solvent components, the etching solution 110 remains within the recess 100; on the other hand, the side surface 104b of the recess forming surface 104 is exposed. Additionally, there are differences... Figure 7 (c) is the case where a portion of the bottom surface 104a of the recessed surface 104 is exposed.

[0123] like Figure 7 As shown in (d), after the etchant 110 is concentrated, a liquid oxidant supply step (step S4) is performed, supplying liquid oxidant 112 to the upper surface of the substrate W. Since the recessed surface 104 is exposed through the etchant removal step, the liquid oxidant 112 enters the recess 100, thereby effectively hydrophilizing the recessed surface 104 (especially the side surface 104b) (hydrophilization step). Liquid oxidant nozzle 11 (see reference) Figure 3 It functions as a hydrophilic component that hydrophilizes the recessed surface 104 exposed by the concentration of the etching solution 110.

[0124] Subsequently, as Figure 7 As shown in (e), liquid oxidant 112 is removed in the oxidant removal step (step S5). After the oxidant removal step, etch ions 111 remain in the recess 100.

[0125] Subsequently, in the rinsing fluid supply step (step S6), rinsing fluid 113 is supplied to the upper surface of the substrate W. Thus, as... Figure 7 As shown in (f), the flushing fluid 113 enters into the recess 100.

[0126] Because a gas-liquid interface is formed within the recess 100 through the concentration of the etching solution 110, the introduction path of the rinsing solution 113 from the opening of the recess 100 to the gas-liquid interface is in a gas phase state. Therefore, compared to the case where the recess 100 is entirely filled with liquid, the rinsing solution 113 can more easily enter the recess 100. However, if the width W1 of the recess 100 is less than 5 nm, the movement of the rinsing solution 113 into the recess 100 is easily restricted. However, the side surface 104b of the recess forming surface 104 is hydrophilized by the liquid oxidant 112. Therefore, the rinsing solution 113 can smoothly enter the recess 100.

[0127] A recess 100 with a width W1 of less than 5 nm constitutes a diffusion layer where ion diffusion, rather than fluid movement, plays a dominant role. The rinsing solution 113 entering the recess 100 comes into contact with the etching solution 110, thus creating an ion concentration difference (concentration gradient) between the rinsing solution 113 and the etching solution 110 within the recess 100. More specifically, the etching solution 110, with a high concentration of etching ions 111, comes into contact with the rinsing solution 113, which contains no etching ions 111. Therefore, to homogenize the concentration of etching ions 111, such as... Figure 7 As shown in (g), etch ions 111 diffuse into the rinsing solution 113 (ion diffusion step). Thus, after the hydrophilization step, an ion diffusion step is performed by supplying rinsing solution 113 to the upper surface of the substrate W, causing etch ions 111 to diffuse into the rinsing solution 113. Subsequently, most of the etch ions 111 move outside the recess 100, and the amount of etch ions 111 remaining in the recess 100 is reduced.

[0128] Subsequently, in the rinsing solution removal step (step S7), rinsing solution is removed from the upper surface of the substrate W. During the rinsing solution supply step, etched ions 111 diffuse into the rinsing solution 113, and most of the etched ions 111 are discharged outside the substrate W along with the rinsing solution 113. Therefore, as... Figure 7 As shown in (h), the rinsing fluid 113 can be removed from the recess 100. Furthermore, it is possible to prevent the rinsing fluid 113 from becoming concentrated during the rinsing fluid removal step, thus preventing etch ions 111 from remaining in the recess 100. In this way, the rinsing fluid 113 functions as a liquid that diffuses etch ions 111 into the liquid by generating a concentration gradient of etch ions 111.

[0129] In the above-described substrate processing, the hydrophilization of the recessed surface 104, performed between the supply of the etching solution 110 and the supply of the rinsing solution 113, is achieved by the supply of the liquid oxidant 112, i.e., the liquid. Therefore, unlike the case where the hydrophilization of the recessed surface 104 is performed by the supply of a gaseous oxidant or by light irradiation (for example, the second embodiment described later), it is not necessary to move the substrate W to another chamber for hydrophilization. Therefore, the substrate processing can be performed quickly.

[0130] Furthermore, in the above-described substrate processing, before supplying the rinsing solution 113 to the upper surface of the substrate W, the liquid oxidant 112 is removed from the upper surface of the substrate W by evaporation. Therefore, it is possible to prevent the oxidant (ozone or hydrogen peroxide) in the liquid oxidant 112 from mixing into the rinsing solution 113 supplied to the upper surface of the substrate W, thus preventing an increase in the ion concentration in the rinsing solution 113. Consequently, the reduction of the ion concentration gradient between the concentrated etching solution 110 and the rinsing solution 113 can be suppressed. As a result, the retention of etching solution 110 within the recess 100 can be suppressed.

[0131] Furthermore, in the aforementioned substrate processing, the supply of the etching solution 110 to the upper surface of the substrate W and the evaporation of the solvent components of the etching solution 110 from the upper surface of the substrate W are both performed while the substrate W is held in a rotating chuck 5. Therefore, after etching, the etching solution 110 can be quickly concentrated. In addition, by rotating the rotating chuck 5 at high speed while positioning the opposing member 6 in a depressurization position, the etching solution 110 can be quickly concentrated using the depressurization of the space SP1 in contact with the upper surface of the substrate W.

[0132] The concentration of the etching solution 110 is mainly performed by rotating the substrate W using the rotary chuck 5. Thus, the rotary chuck 5 functions as an etching solution concentration component. Furthermore, the removal of the rinsing solution is also mainly performed by rotating the substrate W using the rotary chuck 5. Therefore, the rotary chuck 5 also functions as a rinsing solution removal component.

[0133] The diffusion of etch ions 111 using rinsing solution 113 can be considered as an infinite dilution of etch solution 110. Furthermore, according to the Nernst equation "R = D·S·(C0-C) / δ", the dilution rate R caused by diffusion increases with a larger concentration gradient. Here, "D" represents the diffusion coefficient, "S" represents the solid surface area, "C0" represents the ion concentration in the concentrated etch solution 110, and "C" represents the ion concentration in rinsing solution 113. "(C0-C) / δ" represents the concentration gradient of the diffusion layer.

[0134] The greater the difference between the ion concentration in the concentrated etchant 110 and the ion concentration in the rinsing solution 113, the higher the replacement efficiency of the etchant 110. Therefore, by supplying the rinsing solution 113 to the substrate W, the etchant 110 can be efficiently removed from the recess 100. In addition, to further improve the replacement efficiency, it is preferable to use water that contains as few ions as possible as the rinsing solution 113, and more preferably, DIW.

[0135] Figure 8 A flowchart illustrating another example of substrate processing in the first embodiment. Figure 8 In the substrate processing shown, after the rinsing solution removal step (step S7), the rinsing solution supply step (step S6) and the rinsing solution removal step (step S7) are each repeated at least once. In other words, the rinsing solution supply step (ion diffusion step) and the rinsing solution removal step are alternately repeated multiple times. Specifically, in the rinsing solution removal step, after the rinsing solution is discharged outside the substrate W, rinsing solution is supplied again from the rinsing solution nozzle 12 towards the upper surface of the substrate W. Furthermore, Figure 8 In this context, "N" refers to a natural number greater than 1.

[0136] According to the substrate processing of this modified example, multiple diffusion processes using the rinsing solution 113 can be performed. Therefore, even if the etching ions 111 remaining in the recess 100 cannot be sufficiently removed by diffusion using the rinsing solution 113 only once, the etching ions 111 remaining in the recess 100 can still be sufficiently removed.

[0137] <Configuration of the substrate processing apparatus in the second embodiment>

[0138] Figure 9 This is a top view illustrating the configuration of the substrate processing apparatus 1P according to the second embodiment of the present invention.

[0139] The substrate processing apparatus 1P of the second embodiment and the substrate processing apparatus 1 of the first embodiment (see reference) Figure 3 The main difference is that the processing unit 2 includes a wet processing unit 2W and a dry processing unit 2D. Figure 9 In the middle, regarding the above Figure 1~ Figure 8 The components shown are identical to those in Figure 1, and their descriptions are omitted. (The following is a separate section.) Figures 10-14 The same applies to China.

[0140] exist Figure 9 In the example, the two processing towers on the IR side of the conveying robot are composed of multiple wet processing units 2W, and the two processing towers on the opposite side of the IR side are composed of multiple dry processing units 2D. The configuration of the wet processing unit 2W in the second embodiment is similar to that in the first embodiment. Figure 3 The configuration shown is the same. Furthermore, in the wet processing unit 2W of the second embodiment, the liquid oxidant nozzle 11 can be omitted (see [reference]). Figure 3 (etc.). The dry processing unit 2D is disposed in the chamber 4 and includes a gas oxidation processing unit 80 that oxidizes the substrate W with a gaseous oxidant.

[0141] Figure 10 This is a schematic cross-sectional view illustrating an example of the configuration of the gas oxidation processing unit 80. The gas oxidation processing unit 80 includes: a heater unit 82 having a heating surface 82a on which a substrate W is placed; and a heat treatment chamber 81 housing the heater unit 82.

[0142] The heater unit 82 is a circular heating plate. The heater unit 82 includes a plate body 82A and a heater 85. The heater unit 82 is also referred to as a heating element.

[0143] The upper surface of the board body 82A forms a heating surface 82a. The heater 85 may also be a resistor built into the board body 82A. The heater 85 can heat the substrate W to a temperature almost equal to the temperature of the heater 85. For example, the heater 85 is configured to heat the substrate W placed on the heating surface 82a within a temperature range above room temperature and below 400°C. Specifically, by connecting the heater 85 to an energizing mechanism 86 such as a power supply, the temperature of the heater 85 can be varied within the temperature range by adjusting the current supplied by the energizing mechanism 86.

[0144] The heat treatment chamber 81 includes: a chamber body 87 opening upwards; and a cover 88 that moves up and down above the chamber body 87 to block the opening of the chamber body 87. The gas oxidation treatment unit 80 includes a cover lifting drive mechanism 89 that moves the cover 88 up and down (in the vertical direction). The chamber body 87 and the cover 88 are sealed by an elastic member 90 such as an O-ring.

[0145] The cover 88, via the cover lifting drive mechanism 89, is positioned at the lower position of the sealed processing space SP2 formed inside the blocking chamber body 87. Figure 10 The position shown by the solid line), and the upper position where the opening is made open by retreating upwards ( Figure 10 The position indicated by the double-dotted line is used for vertical movement. The sealed processing space SP2 is the space in contact with the upper surface of the substrate W. When the cover 88 is in the upper position, the hand H of the transfer robot CR can enter and exit the heat treatment chamber 81.

[0146] The substrate W is held horizontally in a predetermined second holding position by being placed on the heater unit 82. The second holding position is... Figure 10 The position of the substrate W shown is the position of the substrate W held in a horizontal posture.

[0147] The cover lifting drive mechanism 89 may have an electric motor or a cylinder, or other actuators.

[0148] The gas oxidation processing unit 80 further includes: a plurality of lifting pins 83 that penetrate the plate body 82A and move vertically; and a pin lifting drive mechanism 84 that moves the plurality of lifting pins 83 in the vertical direction. The plurality of lifting pins 83 are connected by a connecting plate 91. The plurality of lifting pins 83, by means of the pin lifting drive mechanism 84, cause the connecting plate 91 to rise and fall, and are positioned above the heating surface 82a on the upper part of the supporting substrate W. Figure 10 The position indicated by the double-dotted line), and the top part (upper end) are submerged to a lower position below the heating surface 82a. Figure 10 The pin moves up and down between positions indicated by solid lines. The pin lifting drive mechanism 84 may have an electric motor or a cylinder, or other actuators.

[0149] Multiple lifting pins 83 are respectively inserted into multiple through holes 92 of the heater unit 82 and the chamber body 87. Fluid can also be prevented from entering the through holes 92 from outside the heat treatment chamber 81 by means of a bellows (not shown) surrounding the lifting pins 83.

[0150] The gas oxidation treatment unit 80 has multiple gas inlets 94 for introducing gaseous oxidant into the sealed treatment space SP2 within the heat treatment chamber 81. Each gas inlet 94 is a through hole in the through cover 88.

[0151] A gaseous oxidant is an example of a hydrophilic gas used to hydrophilize the main surface of substrate W. An example of a gaseous oxidant is ozone (O3) gas. However, gaseous oxidants are not limited to ozone gas; they can also be, for example, oxidizing water vapor, superheated water vapor, etc.

[0152] A gaseous oxidant piping 95 is connected to multiple gas inlets 94, supplying gaseous oxidant to the gas inlets 94. The gaseous oxidant piping 95 branches off from the gaseous oxidant supply source (not shown) toward the multiple gas inlets 94. A gaseous oxidant valve 96A is installed on the gaseous oxidant piping 95 to open and close its flow path, and a gaseous oxidant flow regulating valve 96B to adjust the flow rate of gaseous oxidant within the gaseous oxidant piping 95.

[0153] When the gaseous oxidant valve 96A is opened, gaseous oxidant is introduced into the sealed processing space SP2 through multiple gas inlets 94, supplying gaseous oxidant towards the upper surface of the substrate W. The multiple gas inlets 94 are an example of a gaseous oxidant supply component.

[0154] Multiple gas inlets 94 can also be configured to supply inactive gases in addition to gaseous oxidants (see reference). Figure 10 (The double-dotted line). Alternatively, inactive gases can be mixed into the gaseous oxidant introduced into the sealed processing space SP2, and the concentration (partial pressure) of the oxidant can be adjusted by the degree of mixing of inactive gases.

[0155] The gas oxidation treatment unit 80 includes multiple exhaust ports 97 formed in the chamber body 87 for exhausting the internal ambient gas of the heat treatment chamber 81. Each exhaust port 97 is connected to an exhaust pipe 98, and an exhaust valve 99 is installed on the exhaust pipe 98 to open and close its flow path.

[0156] <An example of substrate processing in the second embodiment>

[0157] Figure 11 This is a schematic diagram illustrating the case of substrate W when substrate processing is performed by the substrate processing apparatus 1P according to the second embodiment. Substrate processing according to the second embodiment and substrate processing according to the first embodiment (see reference). Figure 5 The main difference lies in the hydrophilization of the substrate W through the dry processing unit 2D.

[0158] The following is mainly based on Figure 10 and Figure 11 Regarding the substrate processing of the second embodiment and the substrate processing of the first embodiment (see reference 1) Figure 5 The differences will be explained in detail.

[0159] First, the untreated substrate W is transported by robotic arms IR and CR (see also...). Figure 9 The substrate W is transferred from the conveyor CA to the wet processing unit 2W and then to the rotary chuck 5 (first transfer step: step S10). Thereby, the substrate W is horizontally held by the rotary chuck 5 (first substrate holding step). Then, as... Figure 6A and Figure 6B As shown, the etching solution supply step (step S2) and the etching solution removal step (step S3) are performed.

[0160] After the etching solution removal step, the transfer robot CR enters the wet processing unit 2W, receives the substrate W from the rotary chuck 5, and removes it from the wet processing unit 2W (first removal step: step S11). The substrate W removed from the wet processing unit 2W is transferred by the transfer robot CR into the dry processing unit 2D and handed over to the multiple lifting pins 83 located in the upper position (second loading step: step S12). The multiple lifting pins 83 are moved to the lower position by the pin lifting drive mechanism 84, so that the substrate W is placed on the heating surface 82a. As a result, the substrate W is held horizontally (second substrate holding step).

[0161] Subsequently, by lowering the cover 88, the substrate W is placed on the heating surface 82a of the heater unit 82 within the sealed processing space SP2 formed by the chamber body 87 and the cover 88. The substrate W placed on the heating surface 82a is heated by the heater unit 82 to a predetermined oxidation temperature (substrate heating step, heater heating step). The predetermined oxidation temperature is, for example, a temperature of 100°C or higher and 400°C or lower.

[0162] With the sealed processing space SP2 formed, the gaseous oxidant valve 96A is opened. This performs a gas oxidation process. More specifically, a gaseous oxidant, such as ozone gas, is introduced into the sealed processing space SP2 through multiple gas inlets 94, supplying the gaseous oxidant to the upper surface of the substrate W (gaseous oxidant supply step: step S13). As will be detailed later, the recessed surface 104 (especially the side surface 104b) is oxidized (gas oxidation step, dry oxidation step). That is, the recessed surface 104 (especially the side surface 104b) is hydrophilized (hydrophilization step). The multiple gas inlets 94 function as hydrophilization components for hydrophilizing the recessed surface 104 exposed by the concentration of the etching solution 110.

[0163] The substrate W is heated to the oxidation temperature on the heater unit 82. Therefore, in the gaseous oxidant supply step, a heating oxidation step is performed in which the substrate W is heated to the oxidation temperature while the gaseous oxidant is supplied to the upper surface of the substrate W.

[0164] During the supply of gaseous oxidant, the discharge valve 99 is opened. Therefore, the gaseous oxidant within the enclosed processing space SP2 is discharged through the discharge pipe 98.

[0165] After treating the upper surface of substrate W with a gaseous oxidant, the gaseous oxidant valve 96A is closed. This stops the supply of gaseous oxidant to the sealed processing space SP2. Then, the cover 88 is moved to the upper position.

[0166] After a certain period of gas oxidation treatment, the transport robot CR enters the dry processing unit 2D, receives the oxidized substrate W from the base 72, and removes it from the dry processing unit 2D (second removal step: step S14). Specifically, the pin lifting drive mechanism 84 moves multiple lifting pins 83 to the upper position, and the multiple lifting pins 83 lift the substrate W from the heater unit 82. The transport robot CR receives the substrate W from the multiple lifting pins 83.

[0167] The substrate W, removed from the dry processing unit 2D, is transferred into the wet processing unit 2W by the transfer robot CR and handed over to the rotary chuck 5 (third transfer step: step S15). The substrate W is then held horizontally by the rotary chuck 5 (third substrate holding step). While the rotary chuck 5 holds the substrate W, the rotation of the substrate W is initiated by the rotation drive member 23 (substrate rotation step).

[0168] Subsequently, as Figure 6C and Figure 6D As shown, the flushing fluid supply step (step S6) and the flushing fluid removal step (step S7) are performed.

[0169] Then, the rotation of the substrate W is stopped by the rotation drive member 23. The transfer robot CR enters the wet processing unit 2W, receives the substrate W from the multiple chuck pins 20, and moves it out of the wet processing unit 2W (third removal step: step S16). The substrate W is transferred from the transfer robot CR to the transfer robot IR, and is stored in the conveyor CA by the transfer robot IR.

[0170] Figure 12 This is a schematic diagram illustrating the situation near the upper surface of the substrate W during the substrate processing of the second embodiment. Unlike the substrate processing of the first embodiment, the substrate processing of the second embodiment uses a gaseous oxidant during the oxidation of the main surface of the substrate W.

[0171] In the etching solution supply step (step S2), etching solution is supplied to the upper surface of the substrate W, such as... Figure 12 As shown in (a), the metal layer 103 within the recess 100 is removed (etching step). At the end of the etching solution supply step, as... Figure 12 As shown in (b), preferably, the metal layer 103 within the recess 100 is completely removed.

[0172] Subsequently, in the etchant removal step (step S3), the etchant 110 is discharged outside the substrate W, and the solvent components in the etchant 110 evaporate. Therefore, the etchant is concentrated, as... Figure 12 As shown in (c), the concentrated etching solution 110 remains in the recess 100 (concentration step).

[0173] As described in the first embodiment, if the width W1 of the recess 100 provided on the main surface of the substrate W is less than 5 nm, the recess 100 is very narrow, and the etching solution 110 is easily retained at the bottom of the recess 100.

[0174] Etching solution 110 exists within the recess 100 through the evaporation of the solvent components, while the side surface 104b of the recess forming surface 104 is exposed. There are also differences... Figure 12 (c) shows a portion of the bottom surface 104a of the recessed formation surface 104 exposed. After the etching solution 110 is concentrated, the substrate W is transferred from the wet processing unit 2W to the dry processing unit 2D. Figure 12 As shown in (d), the gaseous oxidant supply step (step S13) is performed by the dry processing unit 2D, supplying gaseous oxidant 114 to the upper surface of the substrate W. Since the recess formation surface 104 is exposed by the etching solution removal step, the gaseous oxidant 114 enters into the recess 100, thereby making the recess formation surface 104 (especially the side surface 104b) well hydrophilized (hydrophilization step).

[0175] Subsequently, the substrate W is transferred from the dry processing unit 2D to the wet processing unit 2W. Then, in the rinsing liquid supply step (step S6), rinsing liquid 113 is supplied to the main surface of the substrate W. Thus, as... Figure 12 As shown in (e), the flushing fluid 113 enters into the recess 100.

[0176] Because a gas-liquid interface is formed within the recess 100 through the concentration of the etching solution 110, the rinsing solution introduction path from the opening of the recess 100 to the gas-liquid interface is in a gas phase state. Therefore, compared to the case where the recess 100 is entirely filled with liquid, the rinsing solution 113 can more easily enter the recess 100. However, if the width W1 of the recess 100 is less than 5 nm, the movement of the rinsing solution 113 into the recess 100 is easily restricted. However, the side surface 104b of the recess forming surface 104 is hydrophilized by the gaseous oxidant 114. Therefore, the rinsing solution 113 can smoothly enter the recess 100.

[0177] A recess 100 with a width W1 of less than 5 nm constitutes a diffusion layer where ion diffusion, rather than fluid movement, plays a dominant role. The rinsing solution 113 entering the recess 100 comes into contact with the etching solution 110, thus creating an ion concentration difference (concentration gradient) between the rinsing solution 113 and the etching solution 110. More specifically, the etching solution 110, with a high concentration of etching ions 111, comes into contact with the rinsing solution 113, which contains no etching ions 111. Therefore, to homogenize the concentration of etching ions 111, such as... Figure 12 As shown in (f), etch ions 111 diffuse into the rinsing solution 113 (ion diffusion step). Thus, after the hydrophilization step, an ion diffusion step is performed by supplying rinsing solution 113 to the upper surface of the substrate W, causing etch ions 111 to diffuse into the rinsing solution 113. Subsequently, most of the etch ions 111 move outside the recess 100, and the amount of etch ions 111 remaining in the recess 100 is reduced.

[0178] Subsequently, in the rinsing solution removal step (step S7), the rinsing solution is removed from the upper surface of the substrate W. Therefore, as... Figure 12 As shown in (g), the rinsing fluid 113 can be removed from the recess 100. During the rinsing fluid supply step, etched ions 111 diffuse into the rinsing fluid 113, and most of the etched ions 111 are discharged to the outside of the substrate W along with the rinsing fluid 113. Therefore, the situation where the rinsing fluid 113 is concentrated and etched ions 111 remain in the recess 100 can be prevented.

[0179] Thus, in the substrate processing of the second embodiment, the recessed surface 104 can be hydrophilized without using a liquid. Therefore, it is possible to prevent the liquid used for hydrophilizing the substrate W (the liquid oxidant of the first embodiment) from mixing into the rinsing solution 113 and causing an increase in the ion concentration in the rinsing solution 113.

[0180] Furthermore, in the aforementioned substrate processing, the supply of etching solution 110 to the upper surface of substrate W and the evaporation of the solvent component of etching solution 110 from the upper surface of substrate W are both performed while substrate W is held in a rotating chuck 5 state. Therefore, after etching, etching solution 110 can be quickly concentrated. In addition, by rotating the rotating chuck 5 at high speed while the opposing member 6 is positioned in a depressurization position, the etching solution can be quickly concentrated through depressurization of the space SP1 in contact with the upper surface of substrate W.

[0181] <Example of a dry processing unit>

[0182] In the dry processing unit 2D, the gas oxidation processing unit 80 can also be replaced by a light irradiation processing unit 70 that generates an oxidant by light irradiation to oxidize the substrate W. Figure 13 This is a schematic cross-sectional view used to illustrate an example of the configuration of the light irradiation processing unit 70.

[0183] The light irradiation processing unit 70 includes: a base 72 having a mounting surface 72a for mounting a substrate W; a light processing chamber 71 for housing the base 72; a light irradiation member 73 for irradiating the upper surface of the substrate W mounted on the mounting surface 72a with light such as ultraviolet light; a plurality of lifting pins 75 that pass through the base 72 and move up and down; and a pin lifting drive mechanism 76 for moving the plurality of lifting pins 75 in the up and down direction.

[0184] A loading / unloading outlet 71a for the substrate W is provided on the side wall of the light processing chamber 71. The light processing chamber 71 has a gate valve 71b for opening and closing the loading / unloading outlet 71a. When the loading / unloading outlet 71a is open, the hand H of the transport robot CR can enter and exit the light processing chamber 71. In this modified example, the substrate W is held horizontally in a predetermined second holding position by being placed on the base 72. The second holding position is... Figure 13 The position of the substrate W shown is the position of the substrate W held in a horizontal posture.

[0185] The light irradiation component 73 includes multiple light irradiation lamps. These lamps may be, for example, xenon lamps, mercury lamps, or deuterium lamps. The light irradiation component 73 is configured to irradiate ultraviolet light, for example, at a wavelength of 1 nm or more and 400 nm or less, preferably at a wavelength of 1 nm or more and 300 nm or less. Specifically, a power supply mechanism 74 is connected to the light irradiation component 73, and power is supplied by the power supply mechanism 74, thereby causing the light irradiation component 73 (the light irradiation lamps) to irradiate light. Through light irradiation, ozone is generated in the ambient gas in contact with the main surface of the substrate W, and this ozone is used to oxidize the upper surface of the substrate W.

[0186] Multiple lifting pins 75 are respectively inserted into multiple through holes 78 in the through base 72 and the light processing chamber 71. The multiple lifting pins 75 are connected by a connecting plate 77. The multiple lifting pins 75 are raised and lowered by a pin lifting drive mechanism 76, supporting the substrate W at an upper position above the mounting surface 72a. Figure 13 The position indicated by the double-dotted line), and the top part (upper end) are recessed to a lower position below the mounting surface 72a. Figure 13 The pin moves up and down between positions indicated by solid lines. The pin lifting drive mechanism 76 may have an electric motor or a cylinder, or other actuators.

[0187] <Other Examples of Substrate Processing in Embodiment 2>

[0188] Figure 14 A flowchart illustrating another example of substrate processing in the second embodiment. Figure 14 The substrate processing shown Figure 11 The difference in the substrate processing shown is that the gaseous oxidant supply step (step S13) is replaced by a light irradiation step (step S20) as a dry oxidation step.

[0189] The following is mainly based on Figure 13 and Figure 14 ,against Figure 14 The substrate processing shown is explained focusing on the differences between it and the substrate processing shown in Figure 1.

[0190] The steps up to the first loading step (step S10) and the first unloading step (step S12) are consistent with... Figure 11 The substrates shown are processed in the same way.

[0191] The substrate W, removed from the wet processing unit 2W, is transferred by the transfer robot CR into the dry processing unit 2D and handed over to multiple lifting pins 75 located in the upper position (second transfer step: step S12). The multiple lifting pins 75 are moved to the lower position by the pin lifting drive mechanism 76, so that the substrate W is placed on the mounting surface 72a. As a result, the substrate W is kept horizontal (second substrate holding step).

[0192] After the transport robot CR retreats outside the dry processing unit 2D, a photoirradiation step (step S20) is performed to irradiate the upper surface of the substrate W. Specifically, power is supplied to the photoirradiation member 73 by the energizing mechanism 74 to begin photoirradiating the substrate W. This oxidizes the recessed surface 104 (especially the side surface 104b) (photoirradiation step, dry oxidation step). That is, the recessed surface 104 (especially the side surface 104b) is hydrophilized (hydrophilization step). The photoirradiation member 73 functions as a hydrophilization member to hydrophilize the recessed surface 104 exposed by the concentration of the etching solution 110.

[0193] Figure 14 In the substrate processing of the modified example shown, apart from hydrophilizing the recessed surface 104 by irradiation with light such as ultraviolet light, the condition near the upper surface of the substrate W in the substrate processing is the same as... Figure 12 Same. More specifically, Figure 12 In (a), gaseous oxidant 114 is supplied, but Figure 14 In the substrate processing shown, the gaseous oxidant 114 is replaced by light irradiation with ultraviolet light or the like.

[0194] As described above, wet oxidation (substrate treatment in the first embodiment) performed by liquid oxidant and dry oxidation (substrate treatment in the second embodiment) performed by light irradiation or gaseous oxidant can be selected as needed.

[0195] like Figure 11 and Figure 14 As shown by the double-dotted line, in the substrate processing of the second embodiment, the rinsing liquid supply step (step S6) and the rinsing liquid removal step (step S7) can be repeated at least once after the rinsing liquid removal step (step S7), just like in the substrate processing of the first embodiment. Figure 11 and Figure 14 The “N” in the text is also related to Figure 8 Similarly, it refers to natural numbers greater than 1.

[0196] <Other Implementation Methods>

[0197] This invention is not limited to the embodiments described above, and can be implemented in other ways.

[0198] For example, the substrate processing of each of the above embodiments can be performed even when the short side (width W1) of the recess 100 is greater than 5 nm. However, when the short side (width W1) of the recess 100 is less than 5 nm, the etching solution tends to remain in the recess 100 during the etching solution removal step. Therefore, the substrate processing of each of the above embodiments is particularly effective in diffusing etching ions into the rinsing solution.

[0199] Furthermore, in the etching solution removal step (step S3), it is not necessarily necessary to remove the etching solution by rotating the substrate W. For example, the chamber 4 of the wet processing unit 2W can be depressurized to evaporate the solvent components in the etching solution (depressurization evaporation step). Alternatively, after the etching solution supply step, the substrate W can be transferred to the heat treatment chamber 81 of the dry processing unit 2D, where the solvent components of the etching solution can be evaporated (depressurization evaporation step). In this case, a depressurization device (not shown) such as a vacuum pump must be provided to depressurize the space inside the heat treatment chamber 81.

[0200] In the etching solution removal step (step S3), the heat treatment chamber 81 can be depressurized while the substrate W is heated, or the heat treatment chamber 81 can be depressurized while the substrate W is heated (heating evaporation step).

[0201] Furthermore, the substrate processing in each of the above embodiments is performed on the upper surface of the substrate W. However, each substrate processing may also be performed on the lower surface of the substrate W.

[0202] Alternatively, processing unit 2 can replace wet processing unit 2W and dry processing unit 2D, and has multiple processing liquid storage tanks for storing etching solution, liquid oxidant, and rinsing solution respectively. That is, substrate processing apparatus 1 can also be a batch substrate processing apparatus. In this case, substrate processing can be performed by sequentially immersing substrate W in the processing liquid in each processing liquid storage tank.

[0203] Furthermore, while the above embodiments use terms such as "horizontal" and "vertical," they do not need to be strictly "horizontal" or "vertical." That is, these various representations allow for deviations in manufacturing precision, setting precision, etc.

[0204] The embodiments of the present invention have been described in detail above, but these are merely specific examples used to illustrate the technical content of the present invention and are not intended to limit the scope of the invention to these specific examples. The scope of the present invention is defined only by the claims.

[0205] This application corresponds to Japan Patent Application No. 2021-045187, filed with the Japan Patent Office on March 18, 2021, all disclosures of which are incorporated herein by reference.

[0206] [Explanation of the labels in the attached diagram]

[0207] 1: Substrate processing device

[0208] 1P: Substrate processing device

[0209] 5: Rotary chuck (substrate holding component, etching solution concentration component, rinsing solution removal component)

[0210] 10: Etching solution nozzle (etching solution supply component)

[0211] 11: Liquid oxidant nozzle (hydrophilized component)

[0212] 12: Fluid nozzle (fluid supply component)

[0213] 73: Light-illuminating components (hydrophilized components)

[0214] 94: Gas inlet (hydrophilic component)

[0215] 100: Concave

[0216] 103: Metal layer (the layer to be removed)

[0217] 104: Concave forming surface

[0218] 110: Etching solution

[0219] 111: Etching Ions

[0220] 112: Liquid oxidant

[0221] 113: Flushing fluid

[0222] 114: Gaseous oxidant

[0223] A1: Axis of rotation

[0224] W: substrate

Claims

1. A substrate processing method comprising processing a substrate having a main surface including a recess forming surface, and forming a removed layer within the recess, the substrate processing method comprising: In the etching step, an etching solution containing etching ions is supplied to the main surface of the substrate to etch the layer to be removed. In the concentration step, after the etching solution is supplied to the main surface of the substrate in the etching step, the etching solution on the main surface of the substrate is concentrated without the step of supplying rinsing solution to the main surface of the substrate. The hydrophilization step involves hydrophilizing the recessed surface exposed by the concentration of the etching solution after the concentration step, without supplying rinsing solution to the main surface of the substrate. In the ion diffusion step, after the hydrophilization step described above, the etched ions are diffused into the rinsing solution by supplying a rinsing solution to the main surface of the substrate; and The rinsing solution removal step removes the rinsing solution from the main surface of the substrate.

2. The substrate processing method as described in claim 1, wherein, The width of the aforementioned recess is less than 5 nm.

3. The substrate processing method as described in claim 1 or 2, wherein, The layer that was removed was a metal layer.

4. The substrate processing method as described in claim 1 or 2, wherein, The above-mentioned ion diffusion step includes: using the ion concentration gradient generated by the contact between the rinsing solution and the etching solution in the above-mentioned recess to diffuse the etching ions into the rinsing solution.

5. The substrate processing method as described in claim 1 or 2, wherein, After the above-mentioned rinsing solution removal step, the above-mentioned ion diffusion step and the above-mentioned rinsing solution removal step are each repeated at least once.

6. The substrate processing method as described in claim 1 or 2, wherein, The above-mentioned hydrophilization step includes an oxidation step of oxidizing the above-mentioned recessed surface.

7. The substrate processing method as described in claim 6, wherein, The oxidation step described above includes a liquid oxidant supply step of supplying liquid oxidant to the main surface of the substrate.

8. The substrate processing method as described in claim 7, wherein, It also includes an oxidant removal step, which removes the liquid oxidant supplied to the main surface of the substrate from the main surface of the substrate before the ion diffusion step described above.

9. The substrate processing method as described in claim 6, wherein, The oxidation step described above includes at least one of the following dry oxidation steps: supplying a gaseous oxidant to the main surface of the substrate and irradiating the main surface of the substrate with light.

10. The substrate processing method as described in claim 1 or 2, wherein, The above concentration step includes a drying step that dries the main surface of the substrate.

11. The substrate processing method as described in claim 10, wherein, The etching step described above includes an etching solution supply step of spraying the etching solution from an etching solution nozzle toward the main surface of the substrate held by the substrate holding member and supplying the etching solution to the main surface of the substrate. The drying step described above includes a rotary evaporation step in which the substrate is rotated by rotating the substrate holding member around a rotation axis that passes through the center of the main surface of the substrate and is orthogonal to the main surface of the substrate, thereby causing the solvent components contained in the etching solution to evaporate from the main surface of the substrate.

12. The substrate processing method as described in claim 10, wherein, The drying step described above includes a decompression evaporation step, in which the solvent components contained in the etching solution evaporate from the main surface of the substrate by decompressing the space in contact with the main surface of the substrate.

13. A substrate processing apparatus for processing a substrate having a main surface including a recess forming surface, and a layer to be removed being formed within the recess, wherein... The substrate processing apparatus includes: The etching solution supply component supplies an etching solution containing etching ions and etching the layer to be removed to the main surface of the substrate. An etching solution concentration component, after supplying the etching solution to the main surface of the substrate, concentrates the etching solution on the main surface of the substrate without the step of supplying rinsing solution to the main surface of the substrate; The hydrophilic component hydrophilizes the recessed surface exposed by the concentration of the etching solution after the etching solution is concentrated, without the step of supplying rinsing solution to the main surface of the substrate. The rinsing fluid supply component supplies rinsing fluid, which allows the etched ions to diffuse into the liquid, to the main surface of the substrate; and The rinsing fluid removal component removes the rinsing fluid from the main surface of the substrate.

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