Substrate processing method, substrate processing apparatus, and substrate processing system

Abstract

Provided are a substrate processing method, a substrate processing apparatus, and a substrate processing system that suppress damage due to plasma.　This substrate processing method comprises: a step for preparing a substrate having a metal film and an insulating film on the surface; a step for supplying an aromatic compound to the substrate and selectively forming a blocking layer on the metal film; a step for selectively forming a target film on the insulating film using the formed blocking layer; and a step for applying a first heat treatment to the substrate and removing the blocking layer on the metal film.

Description

SUBSTRATE PROCESSING METHOD, SUBSTRATE PROCESSING APPARATUS, AND SUBSTRATE PROCESSING SYSTEM

[0001] The present disclosure relates to a substrate processing method, a substrate processing apparatus, and a substrate processing system.

[0002] Patent Document 1 discloses a method for processing a substrate, including the steps of providing a substrate containing a dielectric layer and a metal layer, exposing the substrate to a reactive gas containing molecules that form a self-assembled monolayer on the substrate, and then exposing the substrate containing the SAM to a deposition gas to selectively deposit a metal oxide film on the surface of the dielectric layer relative to the surface of the metal layer.

[0003] Patent No. 7330664

[0004] In one aspect, the present disclosure provides a substrate processing method, a substrate processing apparatus, and a substrate processing system that suppress damage caused by plasma.

[0005] In order to solve the above problem, according to one aspect, there is provided a substrate processing method comprising the steps of: preparing a substrate having a metal film and an insulating film on a surface thereof; supplying an aromatic compound to the substrate to selectively form a blocking layer on the metal film; selectively forming a target film on the insulating film using the formed blocking layer; and performing a first heat treatment on the substrate to remove the blocking layer on the metal film.

[0006] According to one aspect, it is possible to provide a substrate processing method, a substrate processing apparatus, and a substrate processing system that suppress damage caused by plasma.

[0007] FIG. 1 is a diagram showing an example of a processing system PS according to the present embodiment. FIG. 2 is a diagram showing an example of a processing apparatus. FIG. 3 is an example of a flowchart illustrating a substrate processing method according to the present embodiment. FIG. 4 is an example of a schematic view showing the structure of a substrate W in each step of the substrate processing method according to the present embodiment. FIG. 5 is an example of a schematic view showing the structure of a substrate W in each step of the substrate processing method according to the present embodiment. FIG. 6 is an example of a schematic view showing the structure of a substrate W in each step of the substrate processing method according to the present embodiment. FIG. 7 is an example of a schematic view showing the structure of a substrate W in each step of the substrate processing method according to the present embodiment. FIG. 8 is an example of a schematic view showing the structure of a substrate W in each step of the substrate processing method according to the present embodiment.

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] [Processing System] An example of a processing system PS according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of a processing system PS according to this embodiment.

[0010] The processing system PS includes processing devices PM1 to PM4, a vacuum transfer chamber VTM, load lock chambers LL1 to LL3, an atmospheric transfer chamber LM, load ports LP1 to LP3, and a general control unit CU.

[0011] The processing devices PM1 to PM4 are connected to the vacuum transfer chamber VTM via gate valves G11 to G14, respectively. The interior of each of the processing devices PM1 to PM4 is depressurized to a predetermined vacuum atmosphere. Each of the processing devices PM1 to PM4 performs a desired process on a substrate W therein. The processing device PM1 is a device that performs a first process (e.g., a process for forming a blocking layer 430 (see step S102 in FIG. 3 ) described later). The processing device PM2 is a device that performs a second process (e.g., a process for forming a target film 440 (see step S103 in FIG. 3 ) described later). The processing device PM3 is a device that performs a third process (e.g., a process for removing the blocking layer 430 (see step S104 in FIG. 3 ) described later). The processing device PM4 is a device that performs the same process as any of the processing devices PM1 to PM3 or a different process.

[0012] The interior of the vacuum transfer chamber VTM is depressurized to a predetermined vacuum atmosphere. A transport mechanism TR1 is provided inside the vacuum transfer chamber VTM. The transport mechanism TR1 is configured to be able to transport substrates W under a reduced pressure. The transport mechanism TR1 transports substrates W to and from processing devices PM1 to PM4 and load lock chambers LL1 to LL3. The transport mechanism TR1 has, for example, two forks FK11 and FK12 that can move independently. Each of the forks FK11 and FK12 is configured to be able to hold a substrate W.

[0013] The load lock chambers LL1 to LL3 are connected to the vacuum transfer chamber VTM via gate valves G21 to G23, respectively. The load lock chambers LL1 to LL3 are connected to the atmospheric transfer chamber LM via gate valves G31 to G33, respectively. The interior of the load lock chambers LL1 to LL3 can be switched between atmospheric and vacuum atmospheres.

[0014] The atmospheric transfer chamber LM has an atmospheric atmosphere inside. For example, a downflow of clean air is formed inside the atmospheric transfer chamber LM. An aligner AN is provided inside the atmospheric transfer chamber LM. The aligner AN aligns the substrate W. A transport mechanism TR2 is provided in the atmospheric transfer chamber LM. The transport mechanism TR2 transports substrates W to the load lock chambers LL1 to LL3, the carriers C in the load ports LP1 to LP3, and the aligner AN.

[0015] The load ports LP1 to LP3 are provided on the long side walls of the atmospheric transfer chamber LM. A carrier C is attached to each of the load ports LP1 to LP3. The carrier C is, for example, a front opening unified pod (FOUP).

[0016] The overall control unit CU is, for example, a computer. The overall control unit CU includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and an auxiliary storage device. The CPU operates based on programs stored in the ROM or the auxiliary storage device, and controls each component of the processing system PS. For example, the overall control unit CU executes the operation of processing devices PM1 to PM4, the operation of transport mechanisms TR1 and TR2, the opening and closing of gate valves G11 to G14, G21 to G23, and G31 to G33, and the switching of the atmosphere in load lock chambers LL1 to LL3.

[0017] [Operation of Processing System] An example of the operation of the processing system PS according to this embodiment will be described with reference to Fig. 1. The following description will be given taking as an example a case where the processing system PS performs a substrate processing method (see Fig. 3) described below. The operation of the processing system PS according to this embodiment is performed under the control of the overall control unit CU.

[0018] First, the carrier C containing a plurality of substrates W is attached to the load port LP1.

[0019] Next, the transport mechanism TR2 transports the substrate W accommodated in the carrier C to the aligner AN. Next, the aligner AN aligns the substrate W. Next, the overall control unit CU switches the gate valve G31 from a closed state to an open state. Next, the transport mechanism TR2 receives the substrate W from the aligner AN and transports it to the load lock chamber LL1, which is in an atmospheric atmosphere. Next, the overall control unit CU switches the gate valve G31 from an open state to a closed state. Next, the overall control unit CU switches the atmosphere in the load lock chamber LL1 from an atmospheric atmosphere to a vacuum atmosphere.

[0020] Next, the overall control unit CU switches the closed gate valves G11 and G21 to an open state. Next, the transport mechanism TR1 receives the substrate W from the load lock chamber LL1 and transports it to the processing device PM1. Next, the overall control unit CU switches the open gate valves G11 and G21 to a closed state.

[0021] Next, the processing device PM1 performs a first process (a process for forming a blocking layer 430 (see step S102 in FIG. 3) described later).

[0022] Next, the overall control unit CU switches the closed gate valves G11 and G12 to an open state. Next, the transport mechanism TR1 receives the substrate W from the processing device PM1 and transports it to the processing device PM2. Next, the overall control unit CU switches the open gate valves G11 and G12 to a closed state.

[0023] Next, the processing device PM2 performs a second process (a process for forming a target film 440 (see step S103 in FIG. 3) described later).

[0024] Next, the overall control unit CU switches the closed gate valves G12 and G13 to an open state. Next, the transport mechanism TR1 receives the substrate W from the processing device PM2 and transports it to the processing device PM3. Next, the overall control unit CU switches the open gate valves G12 and G13 to a closed state.

[0025] Next, the processing device PM3 performs a third process (for example, a process of removing the blocking layer 430 (see step S104 in FIG. 3) described later).

[0026] Next, the overall control unit CU switches the gate valves G13 and G23, which were closed, to an open state. Next, the transport mechanism TR1 receives the substrate from the processing device PM4 and transports it to the load lock chamber LL3, which has a vacuum atmosphere. Next, the overall control unit CU switches the gate valves G13 and G23, which were open, to a closed state. Next, the overall control unit CU switches the atmosphere inside the load lock chamber LL3 from a vacuum atmosphere to an air atmosphere.

[0027] Next, the overall control unit CU switches the gate valve G33, which is closed, to an open state. Next, the transport mechanism TR2 receives the substrate W from the load lock chamber LL3, transports it to the carrier C attached to the load port LP3, and stores the substrate W in the carrier C. This completes the processing of one substrate W.

[0028] In the operation of the processing system PS described above, the substrate W is transferred from the atmospheric transfer chamber LM to the vacuum transfer chamber VTM via the load lock chamber LL1, and from the vacuum transfer chamber VTM to the atmospheric transfer chamber LM via the load lock chamber LL3. However, the transfer route of the substrate W is not limited to this. The substrate W may be transferred from the atmospheric transfer chamber LM to the vacuum transfer chamber VTM via any of the load lock chambers LL1 to LL3. The substrate W may be transferred from the vacuum transfer chamber VTM to the atmospheric transfer chamber LM via any of the load lock chambers LL1 to LL3.

[0029] [Processing Device 1] Next, an example of processing devices PM1 to PM4 will be described using processing device 1 shown in Fig. 2. Fig. 2 is a diagram showing an example of processing device 1. Note that processing devices PM2 to PM4 may also have a similar configuration.

[0030] The processing apparatus 1 includes a substantially cylindrical airtight processing vessel 2. An exhaust chamber 21 is provided in the center of the bottom wall of the processing vessel 2.

[0031] The exhaust chamber 21 has, for example, a substantially cylindrical shape that protrudes downward. An exhaust flow path 22 is connected to the exhaust chamber 21, for example, at a side surface of the exhaust chamber 21.

[0032] An exhaust unit 24 is connected to the exhaust flow path 22 via a pressure adjustment unit 23. The pressure adjustment unit 23 includes a pressure adjustment valve such as a butterfly valve. The exhaust flow path 22 is configured so that the pressure inside the processing vessel 2 can be reduced by the exhaust unit 24. A transfer port 25 is provided on the side of the processing vessel 2. The transfer port 25 is configured to be freely opened and closed by a gate valve 26. The substrate W is loaded and unloaded between the processing vessel 2 and a transfer chamber (not shown) via the transfer port 25.

[0033] A mounting table 3 for holding a substrate W substantially horizontally is provided within the processing chamber 2. The mounting table 3 is substantially circular in plan view and supported by a support member 31. A substantially circular recess 32 for mounting a substrate W having a diameter of, for example, 300 mm is formed in the surface of the mounting table 3. The recess 32 has an inner diameter slightly larger (for example, about 1 mm to 4 mm) than the diameter of the substrate W. The depth of the recess 32 is configured to be substantially the same as the thickness of the substrate W. The mounting table 3 is made of a ceramic material such as aluminum nitride (AlN). Alternatively, the mounting table 3 may be made of a metal material such as nickel (Ni). Note that instead of the recess 32, a guide ring for guiding the substrate W may be provided around the periphery of the surface of the mounting table 3.

[0034] A grounded lower electrode 33, for example, is embedded in the mounting table 3. A temperature adjustment mechanism 34 is embedded below the lower electrode 33. The temperature adjustment mechanism 34 adjusts the temperature of the substrate W placed on the mounting table 3 to a set temperature based on a control signal from the control unit 9. If the mounting table 3 is made entirely of metal, the entire mounting table 3 functions as the lower electrode, so the lower electrode 33 does not need to be embedded in the mounting table 3. The mounting table 3 is provided with a plurality of (for example, three) lifting pins 41 for holding and lifting the substrate W placed on the mounting table 3. The lifting pins 41 are made of a material such as alumina (Al ２ O ３ The lift pins 41 may be made of ceramics such as quartz or the like. The lower ends of the lift pins 41 are attached to a support plate 42. The support plate 42 is connected to a lift mechanism 44 provided outside the processing vessel 2 via a lift shaft 43.

[0035] The lifting mechanism 44 is installed, for example, at the bottom of the exhaust chamber 21. The bellows 45 is provided between the lifting mechanism 44 and an opening 211 for the lifting shaft 43 formed in the bottom surface of the exhaust chamber 21. The support plate 42 may be shaped so that it can be raised and lowered without interfering with the support member 31 of the mounting table 3. The lifting pins 41 are configured to be able to be raised and lowered between the upper side and the lower side of the surface of the mounting table 3 by the lifting mechanism 44. In other words, the lifting pins 41 are configured to be able to protrude from the top surface of the mounting table 3.

[0036] A gas supply unit 5 is provided on the ceiling wall 27 of the processing vessel 2 via an insulating member 28. The gas supply unit 5 forms an upper electrode and faces the lower electrode 33. An RF power supply 51 is connected to the gas supply unit 5 via a matching box 511. The frequency of the RF power supply 51 is, for example, 13 MHz to 2.45 GHz. By supplying RF power from the RF power supply 51 to the upper electrode (gas supply unit 5), an RF electric field is generated between the upper electrode (gas supply unit 5) and the lower electrode 33. The gas supply unit 5 includes a hollow gas diffusion chamber 52. A number of holes 53 are arranged, for example, evenly, on the bottom surface of the gas diffusion chamber 52 for dispersing and supplying the processing gas into the processing vessel 2. A heating mechanism 54 is embedded in the gas supply unit 5, for example, above the gas diffusion chamber 52. The heating mechanism 54 is heated to a set temperature by receiving power from a power supply unit (not shown) based on a control signal from the control unit 9.

[0037] A gas supply path 6 is provided in the gas diffusion chamber 52. The gas supply path 6 is connected to the gas diffusion chamber 52. A gas source 61 is connected to the upstream side of the gas supply path 6 via a gas line 62. The gas source 61 includes, for example, supply sources of various process gases, mass flow controllers, and valves (none of which are shown). The various process gases include the above-mentioned raw material gases and modifying gases. The various process gases are introduced from the gas source 61 into the gas diffusion chamber 52 via the gas line 62.

[0038] The processing device 1 includes a control unit 9. The control unit 9 is, for example, a computer, and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the processing device 1. The control unit 9 may be provided inside the processing device 1 or may be provided externally. If the control unit 9 is provided externally to the processing device 1, the control unit 9 can control the processing device 1 via communication means such as wired or wireless.

[0039] 2 has been described as a parallel plate type single wafer processing apparatus, but is not limited to this. It may also be a plasma processing apparatus using microwaves or a plasma processing apparatus using VHF, and is not limited to these.

[0040] Although the processing apparatus 1 has been described as a plasma processing apparatus including the upper electrode (gas supply unit 5), the lower electrode 33, and the RF power supply 51, the present invention is not limited to this. The processing apparatus may be a processing apparatus that omits the upper electrode, the lower electrode 33, and the RF power supply 51 and processes the substrate W with a processing gas without generating plasma.

[0041] [Substrate Processing Method] Next, a substrate processing method according to this embodiment will be described with reference to Fig. 3 and Figs. 4A to 4D. Fig. 3 is an example of a flowchart illustrating the substrate processing method according to this embodiment. Figs. 4A to 4D are example of schematic diagrams showing the structure of a substrate W in each step of the substrate processing method according to this embodiment. Here, a substrate processing method will be described in which a target film 440 is selectively formed on the insulating film 410 of a substrate W having an insulating film 410 and a metal film 420 on its surface.

[0042] In step S101, a substrate W is prepared. Here, the substrate W is transported to the processing apparatus PM1. Fig. 4A is an example of a schematic diagram showing the structure of the substrate W to be prepared.

[0043] The surface of the substrate W includes a region where an insulating film 410 is formed and a region where a metal film 420 is formed. Here, the insulating film 410 is an insulating film containing silicon (Si). Specifically, the insulating film 410 is made of SiO ２ The metal film 420 is one selected from a film, a SiN film, a SiOC film, a SiON film, a SiOCN film, a SiCHO film, etc. The metal film 420 is a film containing a metal element. The metal film 420 is a film having electrical conductivity. Specifically, the metal film 420 is one selected from a Cu film, a Co film, a Ru film, a W film, a Mo film, etc.

[0044] In step S102, a gas containing an aromatic compound is supplied to selectively form a blocking layer 430 on the metal film 420. Here, the processing apparatus PM1 performs processing to form the blocking layer 430 on the substrate W. Fig. 4B is an example of a schematic diagram showing the structure of the substrate W after the blocking layer 430 has been formed.

[0045] A gas containing an aromatic compound is supplied from the gas supply unit 5 into the processing chamber 2. The gas source 61 may include a vaporizer that heats and vaporizes a liquid or solid aromatic compound. This allows the gas containing the aromatic compound to be supplied to the substrate W. The aromatic compound is one of aniline, pyridine, benzene, toluene, cyclohexane, and the like. The aromatic compound is adsorbed onto the metal film 420 due to an interaction between electrons of the aromatic compound and electrons of the metal film 420. That is, the aromatic compound is selectively adsorbed onto the metal film 420 relative to the insulating film 410. As a result, the aromatic compound is adsorbed onto the metal film 420, forming a blocking layer 430. The temperature of the substrate W during the formation of the blocking layer 430 in step S102 is lower than the boiling point of the aromatic compound used to form the blocking layer 430. Specifically, the temperature of the substrate W during the formation of the blocking layer 430 is preferably within a range of, for example, room temperature (25°C) to 150°C.

[0046] In step S103, a target film 440 is formed on the insulating film 410 using the blocking layer 430. Here, the substrate W is transported from the processing apparatus PM1 to the processing apparatus PM2, and the processing apparatus PM2 performs processing to form the target film 440 on the substrate W. FIG. 4C is an example of a schematic diagram showing the structure of the substrate W after the target film 440 has been formed. The target film 440 is, for example, an insulating film. The target film 440 may be, for example, SiO ２ Membrane, Al ２ O ３ film, SiN film, ZrO ２ membrane, HfO ２The blocking layer 430 is one selected from a TiN film, a TiN film, and the like. The temperature of the substrate W when forming the target film 440 in step S103 is lower than the boiling point of the aromatic compound used to form the blocking layer 430. Specifically, the temperature of the substrate W when forming the target film 440 is preferably within a range of, for example, room temperature (25°C) to 150°C. This prevents the blocking layer 430 from being removed by sublimation when forming the target film 440.

[0047] Here, the target film 440 is SiO ２ The process of forming the target film 440 includes a step of supplying a gas containing a metal to the substrate W and a step of supplying a process gas containing a silanol gas to the substrate W. The step of supplying the gas containing a metal and the step of supplying the process gas constitute one cycle, and this cycle is repeated multiple times.

[0048] In the step of supplying a gas containing a metal, the substrate W is exposed to a gas containing a metal (e.g., trimethylaluminum gas) to selectively adsorb a metal-containing catalyst onto the insulating film 410 of the blocking layer 430. In the step of supplying a processing gas containing a silanol gas (e.g., TPSOL: Tris(tert-pentoxy)silanol), the metal-containing catalyst adsorbed onto the insulating film 410 is reacted with the silanol gas to form SiO ２ Then, the process of supplying a gas containing a metal and the process of supplying a processing gas constitute one cycle, and this cycle is repeated multiple times to form a target film 440 having a desired film thickness.

[0049] However, the method for forming the target film 440 is not limited to this.

[0050] For example, the step of forming the target film 440 may be performed by atomic layer deposition (ALD) to form the target film 440 on the substrate W. That is, the step of forming the target film 440 includes a step of supplying a source gas (silicon-containing gas, metal-containing gas) to the substrate W and a step of supplying a reactive gas (oxidizing gas, nitriding gas) to the substrate W, and the step of supplying the source gas and the step of supplying the reactive gas constitute one cycle, and this cycle may be repeated multiple times.

[0051] Furthermore, for example, the step of forming the target film 440 may be performed by a chemical vapor deposition (CVD) method to form the target film 440 on the substrate W. That is, the step of forming the target film 440 may include a step of simultaneously supplying a source gas (silicon-containing gas, metal-containing gas) and a reactive gas (oxidizing gas, nitriding gas) to the substrate W.

[0052] In step S104, the blocking layer 430 is removed by annealing. Here, the substrate W is transported from the processing apparatus PM2 to the processing apparatus PM3, and the processing for removing the blocking layer 430 is performed on the substrate W in the processing apparatus PM3. Fig. 4D is an example of a schematic diagram showing the structure of the substrate W after the blocking layer 430 has been removed.

[0053] Here, an inert gas (e.g., N ２ The substrate W is subjected to a heat treatment (first heat treatment) in an atmosphere of an aromatic gas (H2O, H2O, Ar gas, etc.). The temperature of the heat treatment of the substrate W in step S104 is higher than the boiling point of the aromatic compound used to form the blocking layer 430. Specifically, the heat treatment temperature is preferably within a range of, for example, 80°C to 400°C.

[0054] Alternatively, instead of subjecting the substrate W to the heat treatment (first heat treatment), the blocking layer 430 may be removed by exposing it to a solvent. In this case, instead of the treatment device PM3, for example, a wet treatment device that treats the substrate W by dropping a solvent onto it while rotating it can be used. The solvent is, for example, IPA. Exposing the substrate W to the solvent can produce the same effect as the heat treatment (first heat treatment).

[0055] As described above, according to the substrate processing method shown in FIG. 3 , the target film 440 can be selectively formed on the insulating film 410 without using plasma. That is, the blocking layer 430 can be formed without using plasma, and the blocking layer 430 can be removed without using plasma. This prevents damage to the insulating film 410, the metal film 420, and the target film 440 caused by plasma. For example, the resistance values ​​of the insulating film 410, the metal film 420, and the target film 440 can be prevented from being affected by exposure to plasma.

[0056] After the step of forming the blocking layer 430 (step S102) and before the step of forming the target film 440 (step S103), a step of subjecting the substrate W to a heat treatment (second heat treatment) may be added. ２ The substrate W is subjected to a heat treatment (second heat treatment) in an atmosphere of an aromatic gas (e.g., HCl, Ar gas, etc.). The temperature of this heat treatment is lower than the boiling point of the aromatic compound used to form the blocking layer 430. The temperature of this heat treatment may also be higher than the temperature of the substrate W when the blocking layer 430 is formed. Specifically, the temperature of this heat treatment is preferably within a range of, for example, room temperature (25°C) to 150°C. Here, supplying the aromatic compound to the substrate W in step S102 may result in the aromatic compound also adhering to the insulating film 410. The heat treatment desorbs the aromatic compound remaining on the insulating film 410. It also prevents the blocking layer 430 adsorbed on the metal film 420 from being removed. The process of subjecting the substrate W to the heat treatment (second heat treatment) is preferably performed in the same processing apparatus PM2 as the processing apparatus PM2 used to form the target film 440 (step S103).

[0057] Furthermore, instead of subjecting the substrate W to the heat treatment (second heat treatment), the aromatic compound on the insulating film 410 may be dissolved and removed by exposing the substrate W to a solvent. The solvent is, for example, IPA. Exposing the substrate W to the solvent can produce the same effect as the heat treatment (second heat treatment).

[0058] Alternatively, the substrate processing method may include repeating a cycle of forming the blocking layer 430 (step S102) and forming the target film 440 (step S103) a plurality of times, and then performing a heat treatment (first heat treatment) on the substrate W to remove the blocking layer 430 (step S104). This allows the thickness of the target film 440 formed on the insulating film 410 to be increased.

[0059] Alternatively, the substrate processing method may include a step of forming the blocking layer 430 (step S102), a step of subjecting the substrate W to a heat treatment (second heat treatment), and a step of forming the target film 440 (step S103), which constitute one cycle, repeated a plurality of times, and then a step of subjecting the substrate W to a heat treatment (first heat treatment) to remove the blocking layer 430 (step S104). This allows the thickness of the target film 440 formed on the insulating film 410 to be increased.

[0060] Although the process of forming the blocking layer 430 (step S102) is performed in the processing apparatus PM1, the process of forming the target film 440 (step S103) is performed in the processing apparatus PM2, and the process of removing the blocking layer 430 (step S104) is performed in the processing apparatus PM3, the present invention is not limited to this. The process of forming the blocking layer 430 (step S102), the process of forming the target film 440 (step S103), and the process of removing the blocking layer 430 (step S104) may be performed in a single processing vessel.

[0061] Next, the effect of forming the blocking layer 430 using an aromatic compound will be described with reference to Figures 5A to 5C and Figures 6A to 6B. Figures 5A to 5C are exemplary top view schematics showing the area where the blocking layer is formed. Figures 6A to 6B are exemplary schematic views showing the structure of the substrate in each step of the substrate processing method according to the reference example. Figures 5A to 5C show the substrate surface near the boundary between the insulating film 410 and the metal film 420.

[0062] 5A is a schematic diagram of a case where a blocking layer 430 is formed using an aromatic compound. Here, an example will be described in which pyridine is used as the aromatic compound. The blocking layer 430 is formed by adsorbing pyridine onto the metal film 420. Note that the blocking layer 430 is formed by adsorbing pyridine in layers so as to completely cover the surface of the metal film 420, but FIG. 5A illustrates only a portion of the pyridine.

[0063] By forming the blocking layer 430 using an aromatic compound, a part of the aromatic compound protrudes from the boundary between the insulating film 410 and the metal film 420 onto the insulating film 410 side. The protrusion amount La is equal to or less than the size of one molecule of a six-membered ring.

[0064] 5B is a schematic top view of a case where a blocking layer 436 is formed using graphene. The graphene blocking layer 436 is formed on the metal film 420. Note that although the blocking layer 436 is formed of multiple layers of graphene, only one layer of graphene is shown in FIG. 5B.

[0065] Here, the six-membered rings are bonded to each other to form graphene, and the blocking layer 436 grows in the lateral direction. As a result, the graphene (blocking layer 436) protrudes from the boundary between the insulating film 410 and the metal film 420 onto the insulating film 410 side. That is, the graphene (blocking layer 436) is also formed on the insulating film 410, protruding by a protrusion amount Lb. Note that the protrusion amount Lb is equal to or greater than the size of one molecule of the six-membered ring.

[0066] FIG. 5C is a schematic diagram of a case where a blocking layer 437 is formed using a self-assembled monolayer (SAM). The blocking layer 437 of the self-assembled monolayer is formed on the metal film 420. Here, the organic compound that forms the self-assembled monolayer has a main chain (chain portion) and a functional group formed at one end of the main chain. The main chain is formed by a series of carbon atoms (C). The main chain is formed, for example, by an alkyl chain. The functional group is a functional group that selectively adsorbs (bonds) to the metal film 420. The functional group of the organic compound adsorbs to the surface of the metal film 420, and the organic compounds are oriented due to interactions between the organic compounds, thereby forming a self-assembled monolayer.

[0067] Here, some molecules have main chains that do not extend vertically and fall onto the metal film 420. As a result, the SAM protrudes from the boundary between the insulating film 410 and the metal film 420 onto the insulating film 410 side. That is, the SAM (blocking layer 437) is formed on the insulating film 410 by a protrusion amount Lc. The protrusion amount Lc depends on the length of the main chain.

[0068] 6A and 6B are exemplary schematic diagrams showing the structure of a substrate W when the blocking layers 436, 437 are formed using graphene or a self-assembled monolayer. When the blocking layers 436, 437 are formed using graphene or a self-assembled monolayer, the blocking layers 436, 437 are formed so as to extend onto the insulating film 410 as well, as shown in FIG. 6A. In this case, the substrate W is subjected to plasma treatment to remove portions of the blocking layers 436, 437. As a result, the blocking layers 436, 437 extending onto the insulating film 410 are removed, and the blocking layers 436, 437 are selectively formed on the metal film 420, as shown in FIG. 6B.

[0069] Furthermore, the process of forming the blocking layers 436, 437 and the process of removing the blocking layers 436, 437 that protrude onto the insulating film 410 by plasma treatment constitute one cycle, and this cycle is repeated multiple times to selectively form the blocking layers 436, 437 on the metal film 420.

[0070] In this way, by forming blocking layer 430 using an aromatic compound (step S102 in FIG. 3, see FIG. 5A), the amount of protrusion onto insulating film 410 can be reduced compared to when blocking layers 436, 437 are formed using graphene or a self-assembled monolayer (see FIGS. 5B, 5C, 6A and 6B).

[0071] Furthermore, by forming the blocking layer 430 using an aromatic compound, it is possible to reduce the need for plasma treatment for removing the blocking layers 436 and 437 that protrude onto the insulating film 410. Thus, by forming the blocking layer 430 using an aromatic compound, it is possible to suppress damage to the insulating film 410 by plasma.

[0072] Furthermore, when removing the blocking layer 430 formed using an aromatic compound (step S104 in FIG. 3 ), it can be removed by annealing. On the other hand, when removing the blocking layers 436 and 437 formed using graphene or a self-assembled monolayer, they are removed by plasma treatment. Thus, by forming the blocking layer 430 using an aromatic compound, it is possible to suppress damage to the insulating film 410 by plasma when removing the blocking layer 430.

[0073] Furthermore, when removing the blocking layer 430 formed using an aromatic compound (step S104 in FIG. 3), it can be removed by wet treatment. Thus, by forming the blocking layer 430 using an aromatic compound, it is possible to prevent the insulating film 410 from being damaged by plasma when removing the blocking layer 430.

[0074] The substrate processing method has been described above, but the present disclosure is not limited to the above-described embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims.

[0075] This application claims priority based on Japanese Patent Application No. 2024-012150, filed on January 30, 2024, the entire contents of which are incorporated herein by reference.

[0076] 410 insulating film 420 metal film 430 blocking layer 440 target film

Claims

1. A substrate processing method comprising the steps of: preparing a substrate having a metal film and an insulating film on its surface; supplying an aromatic compound to the substrate to selectively form a blocking layer on the metal film; using the formed blocking layer to selectively form a target film on the insulating film; and performing a first heat treatment on the substrate to remove the blocking layer on the metal film.

2. The substrate processing method according to claim 1, wherein the temperature at which the blocking layer is formed is lower than the boiling point of the aromatic compound.

3. The substrate processing method according to claim 1, wherein the temperature at which the target film is formed is lower than the boiling point of the aromatic compound.

4. The substrate processing method according to claim 3, wherein the temperature at which the target film is formed is within a range of 25°C to 150°C.

5. The substrate processing method according to claim 1, wherein the aromatic compound is one of aniline, pyridine, benzene, toluene, and cyclohexane.

6. The substrate processing method according to claim 1, wherein the temperature of the first heat treatment is higher than the boiling point of the aromatic compound.

7. The substrate processing method according to claim 6, wherein the temperature of the first heat treatment is within a range of 80°C to 400°C.

8. The substrate processing method according to claim 1, further comprising the step of subjecting the substrate to a second heat treatment after forming the blocking layer and before forming the target film, thereby removing the aromatic compound remaining on the insulating film.

9. The substrate processing method according to claim 8, wherein the temperature of the second heat treatment is 25°C to 150°C.

10. The substrate processing method according to claim 1, wherein the step of forming the blocking layer and the step of forming the target film are repeated.

11. The substrate processing method according to claim 8, wherein the step of forming the blocking layer, the step of performing the second heat treatment, and the step of forming the target film are repeated.

12. The substrate processing method according to claim 8, wherein the step of desorbing the aromatic compounds remaining on the insulating film and the step of forming the target film are carried out in the same chamber.

13. The substrate processing method according to claim 1, wherein the metal film is one selected from a Cu film, a Co film, a Ru film, a W film, and a Mo film.

14. The insulating film is made of SiO ２ The substrate processing method according to claim 1 , wherein the film is one selected from the group consisting of a SiN film, a SiOC film, a SiON film, a SiOCN film, and a SiCHO film.

15. The target film is SiO ２ Membrane, Al ２ O ３ film, SiN film, ZrO ２ membrane, HfO ２ The substrate processing method according to claim 1 , wherein the film is one selected from the group consisting of a TiN film and a TiN film.

16. The step of selectively forming the target film on the insulating film comprises: a step of supplying a gas containing a metal to the substrate and adsorbing a metal-containing catalyst on the insulating film; and a step of supplying a process gas containing a silanol gas to the substrate and reacting the metal-containing catalyst with the process gas to form SiO as the target film. ２ The substrate processing method according to claim 1 , further comprising:

17. A substrate processing apparatus comprising: a processing vessel; a mounting table disposed within the processing vessel on which a substrate having a metal film and an insulating film on its surface is placed; a gas supply unit that supplies gas into the processing vessel; and a control unit, wherein the control unit performs the steps of: supplying an aromatic compound to the substrate and selectively forming a blocking layer on the metal film; selectively forming a target film on the insulating film using the formed blocking layer; and performing a first heat treatment on the substrate and removing the blocking layer on the metal film.

18. A substrate processing system comprising: a first processing apparatus that supplies an aromatic compound to a substrate having a metal film and an insulating film on its surface, and selectively forms a blocking layer on the metal film; a second processing apparatus that uses the formed blocking layer to selectively form a target film on the insulating film; a third processing apparatus that performs a first heat treatment on the substrate, and removes the blocking layer on the metal film; and a vacuum transfer chamber connected to the first processing apparatus, the second processing apparatus, and the third processing apparatus.

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