Substrate processing method and substrate processing system

Abstract

According to the present disclosure, a substrate treatment method for filling a concave portion of a substrate with a silicon-containing film so as to be able to fill the concave portion of the substrate with a silicon-containing film comprises: (a) a step of exposing the substrate to a plasma generated from a first treatment gas comprising a first silicon-containing gas and a second silicon-containing gas different from the first silicon-containing gas to form a first fluid film having a first viscosity within the concave portion; (b) a step of exposing the substrate to a plasma generated from a first modification gas to modify the first fluid film to form a first silicon-containing film having pores; (c) a step of exposing the substrate to a plasma generated from a second treatment gas comprising the first silicon-containing gas and the second silicon-containing gas to form a second fluid film having a second viscosity lower than the first viscosity within the concave portion and within the pores of the first silicon-containing film; and (d) a step of exposing the substrate to a plasma generated from a second modification gas to modify the second fluid film to form a second silicon-containing film. A substrate processing method is provided.

Description

Technology Field

[0001] The present disclosure relates to a substrate processing method and a substrate processing system. Background Technology

[0002] Patent Document 1 discloses a method for forming a silicon-containing film in a concave portion formed on the surface of a substrate, comprising: (a) a process of exposing a substrate adjusted to a first temperature to a plasma generated from a processing gas containing a halogen-containing silane to form a fluid film in the concave portion; and (b) a process of heat-treating the substrate to a second temperature higher than the first temperature to cure the fluid film. Prior art literature

[0003] Japanese Patent Publication No. JP 2022-111764 The problem to be solved

[0004] In one aspect, the present disclosure provides a substrate processing method and a substrate processing system for filling a concave portion of a substrate with a silicon-containing film. means of solving the problem

[0005] To solve the above problem, according to one aspect, a substrate treatment method for filling a concave area with a silicon-containing film comprises: (a) a step of exposing a substrate to a plasma generated from a first treatment gas comprising a first silicon-containing gas and a second silicon-containing gas different from the first silicon-containing gas to form a first fluid film having a first viscosity within the concave area; (b) a step of exposing the substrate to a plasma generated from a first modification gas to modify the first fluid film to form a first silicon-containing film having a void; (c) a step of exposing the substrate to a plasma generated from a second treatment gas comprising the first silicon-containing gas and the second silicon-containing gas to form a second fluid film having a second viscosity lower than the first viscosity within the concave area and within the void of the first silicon-containing film; and (d) a step of exposing the substrate to a plasma generated from a second modification gas to the A substrate processing method is provided, comprising a process for forming a second silicon-containing film by modifying a second fluid film. Effects of the invention

[0006] According to one aspect, the present disclosure may provide a substrate processing method and a substrate processing system for filling a concave portion of a substrate with a silicon-containing film. Brief explanation of the drawing

[0007] FIG. 1 is a drawing showing an example of a substrate processing system related to one embodiment. FIG. 2 is a flow chart showing an example of a substrate processing method related to one embodiment. Figure 3 is an example of a cross-sectional schematic diagram of a substrate. Figure 4 is an example of a cross-sectional schematic diagram of a substrate. Figure 5 is an example of a cross-sectional schematic diagram of a substrate. Figure 6 is an example of a cross-sectional schematic diagram of a substrate. Figure 7 is an example of a cross-sectional schematic diagram of a substrate. Figure 8 is an example of a chemical reaction equation. Figure 9 is an example of a chemical reaction equation. Figure 10 is an example of a chemical reaction equation. Figure 11 is an example of a chemical reaction equation. Figure 12 is an example of a diagram showing the relationship between the ratio of cross-linking gas and the viscosity of the fluid membrane. Figure 13 is an example of a cross-sectional schematic diagram showing the state of a substrate during CMP processing. Figure 14 is an example of a cross-sectional schematic diagram showing the state of a substrate. Specific details for implementing the invention

[0008] Hereinafter, embodiments for implementing the present disclosure will be described with reference to the drawings. In each drawing, the same reference numerals are assigned to identical components, and redundant descriptions may be omitted.

[0009] [Substrate Processing System]

[0010] A substrate processing system (100) used in a substrate processing method related to one embodiment is described using FIG. 1. FIG. 1 is a drawing showing an example of a substrate processing system (100) related to one embodiment.

[0011] The substrate processing system (100) has a processing device (101–104), a vacuum transfer room (105), a load lock room (301–303), an air transfer room (400), a load port (501–504), and a control device (600).

[0012] Each processing unit (101 to 104) is connected to a vacuum transport chamber (105) through a gate valve (G11 to G14). The inside of the processing units (101 to 104) is depressurized to a predetermined vacuum environment (or atmosphere), and a desired processing is performed on a substrate (W) inside.

[0013] The processing device (101) is a processing device (film forming device) that performs the processing of step S102 of FIG. 2 (processing to form the first fluid film (20)) described later, and forms a fluid film in the concave portion (11) of the substrate (W).

[0014] The processing device (101) is, for example, a plasma-enhanced chemical vapor deposition (CVD) device. The processing device (101) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies a first processing gas into the processing vessel, and a plasma generation unit that generates a plasma of the first processing gas. The control device (600) controls the processing device (101) to generate a plasma of the first processing gas, thereby forming a first fluid film (20) on the substrate (W).

[0015] The processing device (102) is a processing device (heating device) that performs an annealing treatment on the substrate (W) by executing the processing (first annealing treatment) of step S103 of FIG. 2 described later. Additionally, the processing device (102) is a processing device (modification device) that performs a modification treatment on the substrate (W) by executing the processing (first modification treatment) of step S104 of FIG. 2 described later.

[0016] The processing device (102) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies an inert gas (Ar gas) into the processing vessel, and a heating unit that heats the substrate (W). The control device (600) controls the processing device (102) to perform an annealing treatment on the substrate (W) by heating the substrate (W) in an inert gas (Ar gas) environment. Additionally, the processing device (102) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies a first reforming gas into the processing vessel, and a plasma generation unit that generates a plasma of the first reforming gas. The control device (600) controls the processing device (102) to perform a reforming treatment on the substrate (W) by generating a plasma of the first reforming gas.

[0017] The processing device (103) is a processing device (film formation device) that performs the processing of step S105 of FIG. 2 (processing to form the second fluid film (30)) described later, and forms a fluid film in the gap (27) of the substrate (W).

[0018] The processing device (103) is, for example, a plasma-enhanced chemical vapor deposition (CVD) device. The processing device (103) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies a second processing gas into the processing vessel, and a plasma generation unit that generates a plasma of the second processing gas. The control device (600) controls the processing device (103) to generate a plasma of the second processing gas, thereby forming a second fluid film (30) on the substrate (W).

[0019] The processing device (104) is a processing device (heating device) that performs an annealing treatment on the substrate (W) by executing the processing (second annealing treatment) of step S106 of FIG. 2 described later. Additionally, the processing device (104) is a processing device (modification device) that performs a modification treatment on the substrate (W) by executing the processing (second modification treatment) of step S107 of FIG. 2 described later. The processing device (104) has, for example, a VHF plasma source.

[0020] The processing device (104) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies an inert gas (Ar gas) into the processing vessel, and a heating unit that heats the substrate (W). The control device (600) controls the processing device (104) to perform an annealing treatment on the substrate (W) by heating the substrate (W) in an inert gas (Ar gas) environment. Additionally, the processing device (104) has, for example, a processing vessel, a substrate support installed within the processing vessel, a gas supply unit that supplies a second reforming gas into the processing vessel, and a plasma generation unit that generates a plasma of the second reforming gas. The control device (600) controls the processing device (104) to perform a reforming treatment on the substrate (W) by generating a plasma of the second reforming gas.

[0021] For reference, the configuration of the processing apparatus (101 to 104) shown in FIG. 1 is not limited thereto as an example. For instance, the ratio of the number of processing apparatuses (101 to 104) may be appropriately selected. Also, the processing of step S102 and the processing of step S105 may be configured to be executed in the same processing apparatus. Also, the processing of steps S102 and S104 and the processing of steps S105 and S107 may be configured to be executed in the same processing apparatus. Furthermore, regarding the processing apparatuses (102, 104), although it has been described that the annealing treatment and the modification treatment are executed in the same processing apparatus, this is not limited thereto, and the processing apparatus for performing the annealing treatment and the processing apparatus for performing the modification treatment may be configured to be installed as separate processing apparatuses.

[0022] The vacuum transfer chamber (105) is depressurized to a predetermined vacuum environment. The vacuum transfer chamber (105) is an example of a transfer device for transferring a substrate (W). A transfer mechanism (106) capable of transferring the substrate (W) in a depressurized state is installed in the vacuum transfer chamber (105). The transfer mechanism (106) transfers the substrate (W) to the processing device (101-104) and the load lock chamber (301-303).

[0023] The load lock chambers (301–303) are each connected to the vacuum transport chamber (105) through gate valves (G21–G23) and to the atmospheric transport chamber (400) through gate valves (G31–G33). The load lock chambers (301–303) are configured to switch between an atmospheric environment and a vacuum environment.

[0024] The interior of the air transport room (400) is in an atmospheric environment, and, for example, a down flow of clean air is formed. An aligner not shown is installed in the air transport room (400) to perform alignment of the substrate (W). Additionally, a transport mechanism (402) is installed in the air transport room (400). The transport mechanism (402) transports the substrate (W) to the carrier (C) of the load lock room (301-303) and the load port (501-504) described later, and to the aligner.

[0025] Load ports (501–504) are installed on the wall of the waiting transport room (400). A carrier (C) containing a substrate (W) or an empty carrier (C) is installed in the load ports (501–504) through the gate valves (G41–G44). For example, a FOUP (Front Opening Unified Pod) can be used as the carrier (C).

[0026] The control device (600) controls each part of the substrate processing system (100). For example, the control device (600) performs the operation of the processing device (101-104), the operation of the return mechanism (106, 402), the opening and closing of the gate valves (G11-G14, G21-G23, G31-G33, G41-G44), and the switching of the environment within the load lock chamber (301-303).

[0027] [Substrate Processing Method]

[0028] Next, an example of a substrate processing method using the substrate processing system (100) shown in FIG. 1 will be explained using FIG. 2 to FIG. 11. FIG. 2 is a flowchart showing an example of a substrate processing method related to one embodiment. FIG. 3 to FIG. 7 are examples of cross-sectional schematic diagrams of a substrate (W) in each processing step. FIG. 8 to FIG. 11 are examples of chemical reaction equations explaining each processing step.

[0029] Here, a process of embedding a silicon-containing film (third silicon-containing film (40)) within a concave portion (11) of a substrate (W) is described. For reference, the silicon-containing film (third silicon-containing film (40)) embedded within the concave portion (11) is, for example, any one of a SiO film, a SiOC film, a SiOCN film, etc.

[0030] In step S101, a substrate (W) is prepared.

[0031] Here, a carrier (C) containing a substrate (W) is installed in any one of the load ports (501 to 504). Then, the control device (600) controls a conveying mechanism (402), etc., to convey the substrate (W) from the carrier (C) to any one of the load lock chambers (301 to 303). Additionally, the control device (600) controls a conveying mechanism (106), etc., to convey the substrate (W) from any one of the load lock chambers (301 to 303) to the substrate support of the processing device (101).

[0032] FIG. 3 is an example of a cross-sectional schematic diagram of a substrate (W) prepared in step S101. Here, the substrate (W) prepared has a base (10). A concave portion (11) is formed on the upper surface (12) of the base (10).

[0033] For reference, the substrate (W) is described as having a vertical concave portion (11), but is not limited thereto. The substrate (W) has a first concave portion in the vertical direction and a second concave portion extending in the transverse direction (horizontal direction) from the side of the first concave portion, and the substrate treatment shown in FIG. 2 may be a treatment of embedding a silicon-containing film within the second concave portion.

[0034] In step S102, a substrate (W) is exposed to a plasma generated from a first treatment gas containing a first silicon-containing gas and a second silicon-containing gas to form a first fluid film (20) on the substrate (W).

[0035] Here, the control device (600) controls the gas supply unit, plasma generation unit, etc. of the processing device (101) to generate plasma of the first processing gas.

[0036] The first silicon-containing gas is an organic silicon compound gas. Additionally, the first silicon-containing gas is a gas containing monomers of organic silicon compounds. If the silicon-containing film (third silicon-containing film (40)) embedded in the recess (11) is a SiOC film, the first silicon-containing gas contains at least Si, O, and C. Alternatively, if the silicon-containing film (third silicon-containing film (40)) embedded in the recess (11) is a SiOCN film, the first silicon-containing gas contains at least Si, O, C, and N.

[0037] Organic silicon compound gases are represented by the structural formula of the following (1), for example.

[0038] Si α O β (OC m H n ) Г C x H y … (1)

[0039] However, m, n, α are any integer greater than or equal to 1, β, Γ, x, y are any integer greater than or equal to 0, and β and Γ do not both become 0.

[0040] Examples of such compounds include alkoxysilane compounds (alkoxysilane monomers) in which β is 0 and Г is 1 or greater. As for alkoxysilane compounds, (R1) a Si(-O-R2) 4-a(However, R1 is any one of -CH3, -C2H5, -C3H7, -C2H3, and -C2H, R2 is -CH3 or -C2H5, and a is 0, 1, 2, or 3) may be used. Specifically, examples include tetramethoxysilane (TMOS; Si(OCH3)4), methyltrimethoxysilane (MTMOS; Si(OCH3)3CH3), tetraethoxysilane (TEOS; Si(OC2H5)4), dimethyldimethoxysilane (DMDMOS; Si(OCH3)2(CH3)2), triethoxysilane (SiH(OC2H5)3), trimethoxysilane (SiH(OCH3)3), trimethoxydisiloxane (Si(OCH3)3OSi(OCH3)3), etc. These compounds may be used individually or in combination of two or more.

[0041] In addition, as another organic silicon compound gas, Si-C m H n Examples having bonds include, for instance, methyltrimethoxysilane. Furthermore, as other organosilicon compound gases, Si s N t C u H v Examples include silicon compounds represented by (s,v are any integer greater than or equal to 1, and t,u are any integer greater than or equal to 0).

[0042] The second silicon-containing gas contains silicon (Si). In addition, the second silicon-containing gas is a crosslinking gas that crosslinks monomers (organosilicon compounds). The second silicon-containing gas is Si n H 2n+2 A silicon-containing gas represented by (n is an integer greater than or equal to 1) may be used. Examples of such silicon-containing gases include silane (SiH4), disilane (Si2H6), trisilane (Si3H8), and tetrasilane (Si4H4). 10Any one of the following may be used, such as ), and higher silanes. In the following description, silane (SiH4) is used as the second silicon-containing gas.

[0043] Here, the first treatment gas used in step S102 has a higher proportion of the second silicon-containing gas (crosslinking gas) compared to the second treatment gas used in step S105 described later. That is, the ratio of the second silicon-containing gas (crosslinking gas) to the first treatment gas is greater than the ratio of the second silicon-containing gas (crosslinking gas) to the second treatment gas. Specifically, it is preferable that the ratio of the second silicon-containing gas (crosslinking gas) to the first treatment gas be in the range of 0.29 to 0.375.

[0044] In the processing of step S102, the processing temperature of the substrate (W) is preferably within the range of, for example, 20℃ to 100℃. In addition, the processing temperature of the substrate (W) is more preferably within the range of, for example, 25℃ to 50℃.

[0045] FIG. 8 is an example of a chemical reaction equation describing the treatment of step S102. As shown in FIG. 8, an organic silicon compound (first silicon-containing gas) and a silane (second silicon-containing gas) react, and the cross-linking reaction of the organic silicon compound (first silicon-containing gas) proceeds through the silane (second silicon-containing gas) to form a fluid oligomer. Here, the first treatment gas has a higher proportion of the cross-linking gas (second silicon-containing gas) compared to the second treatment gas described later, so the number of molecules of the formed fluid oligomer increases. Accordingly, a first fluid membrane (20) having a first viscosity is formed. For reference, the first viscosity has a higher viscosity than the second viscosity described later.

[0046] FIG. 4 is an example of a cross-sectional schematic diagram of a substrate (W) after processing in step S102. A fluid oligomer is generated by plasma produced from a first processing gas, and the fluid oligomer is introduced into the concave portion (11), thereby filling the concave portion (11) with a first fluid film (20). Additionally, the first fluid film (20) is formed to cover the upper surface (12) of the base (10). The upper surface (21) of the first fluid film (20) is a flat surface.

[0047] In step S103, an annealing treatment is performed. By the annealing treatment, the first fluid film (20) is solidified. The solidified film becomes the first silicon-containing film (25). That is, the first silicon-containing film (25) is formed by the annealing treatment.

[0048] Here, the control device (600) controls the conveying mechanism (106), etc., to convey the substrate (W) from the processing device (101) to the substrate support of the processing device (102). The control device (600) controls the gas supply unit, heating unit, etc., of the processing device (102) to heat the substrate (W) in an inert gas (Ar gas) environment, thereby performing an annealing treatment on the substrate (W). For reference, the annealing treatment of step S103 may be omitted.

[0049] In the processing of step S103, the processing temperature of the substrate (W) is preferably within the range of, for example, 400℃ to 600℃. Additionally, the processing temperature of the substrate (W) is preferably within the range of, for example, 450℃ to 550℃.

[0050] In step S104, a plasma generated from the first reforming gas is exposed to the substrate (W) to reform the first silicon-containing film (25), thereby forming a reformed first silicon-containing film (25). Specifically, the first silicon-containing film (25) is densified.

[0051] Here, the control device (600) controls the gas supply unit, plasma generation unit, etc. of the processing device (102) to generate plasma of the first reformed gas.

[0052] The first reforming gas includes an inert gas (Ar gas) and hydrogen (H2) gas.

[0053] Here, the first reforming gas used in step S104 has a lower proportion of hydrogen (H2) gas compared to the second reforming gas used in step S107 described later. That is, the ratio of hydrogen (H2) gas to the first reforming gas is smaller than the ratio of hydrogen (H2) gas to the second reforming gas.

[0054] In addition, the pressure inside the processing vessel in step S104 is lower than the pressure inside the processing vessel in step S107 described later.

[0055] In addition, the frequency of the high-frequency power supplied when generating plasma in step S104 is a lower frequency compared to the frequency of the high-frequency power supplied when generating plasma in step S107 described later. The processing device (102) has, for example, a CCP plasma source as a plasma generating unit. It is preferable that the frequency of the high-frequency power supplied when generating plasma in step S104 be in the HF band. Specifically, the frequency of the high-frequency power supplied when generating plasma in step S104 is, for example, 3 MHz to 30 MHz (for example, 13.56 MHz).

[0056] FIG. 9 is an example of a chemical reaction equation describing the processing of steps S103 and S104. As shown in FIG. 9, the fluid oligomer of the first fluid membrane (20) undergoes a cross-linking reaction by annealing treatment to form a SiO film (SiOC film, SiOCN film) of the first silicon-containing membrane (25). In addition, the SiO film (SiOC film, SiOCN film) of the first silicon-containing membrane (25) is densified by the plasma of the first reforming gas.

[0057] FIG. 5 is an example of a cross-sectional schematic diagram of a substrate (W) after processing steps S103 and S104. Here, when the first fluid film (20) is solidified and densified by annealing treatment (S103) and modification treatment (S104), it suppresses surface shrinkage and reduces internal volume when forming the first silicon-containing film (25). Here, the first fluid film (20) has high viscosity (first viscosity) to suppress the upper surface (26) of the first silicon-containing film (25) from becoming concave. Additionally, as the volume is reduced, a void (27) is formed inside the first silicon-containing film (25).

[0058] When a low-viscosity fluid membrane is embedded within a depression, solidifying and densifying it through annealing and modification treatments causes the first silicon-containing membrane to shrink and its internal volume to decrease when forming the first silicon-containing membrane. At this time, in the case of a low-viscosity fluid membrane, there is a risk that an unsolidified fluid membrane may flow into the pores, thereby forming a depression on the upper surface of the silicon-containing membrane.

[0059] FIG. 13 is an example of a cross-sectional schematic diagram showing the state of a substrate during Chemical Mechanical Polishing (CMP) treatment. Here, a film (220) having a concave portion (221) is formed on a film (210). A silicon-containing film (230) is formed by embedding a low-viscosity fluid film in the concave portion (221) and solidifying and densifying it through annealing and modification treatments. As the silicon-containing film (230) shrinks, a depression (231) is formed in the silicon-containing film (230). When such a depression (231) is formed, there is a risk that an abrasive (slurry) (240) may accumulate in the depression (231) when CMP treatment is performed on the substrate using a polishing pad (300) in a subsequent process, for example, as shown in FIG. 13.

[0060] FIG. 14 is an example of a cross-sectional schematic diagram showing the state of a substrate. Here, the substrate has a laminated film in which a film (311) and a film (312) are alternately laminated, and a film (313) is formed thereon. In addition, the laminated film has a first concave portion (316) formed in the longitudinal direction (vertical direction) and a second concave portion (317) formed in the film (312) in the transverse direction (horizontal direction) from the first concave portion (316). Here, a silicon-containing film (320) is formed by embedding a fluid film in the side walls of the first concave portion (316) and the second concave portion (317), and solidifying and densifying it through annealing and modification treatments. As shown in FIG. 14 (a), in a configuration having a second concave portion (317) in the transverse direction, when a silicon-containing film (320) is embedded within the second concave portion (317), for example, using a fluid membrane, a recess (321) is formed in the silicon-containing film (320). Therefore, as shown in FIG. 14 (b), when embedding (330) is performed in the first concave portion (316) in the next process, there is a risk that the recess (321) of the silicon-containing film (320) will not be embedded and will become a void (318).

[0061] In this regard, as shown in FIG. 5, if a highly viscous fluid film is embedded in the concave portion and solidified and densified by annealing and modification treatments, the shrinkage of the surface of the first silicon-containing film (25) can be suppressed and internal deposition reduced. Accordingly, the upper surface (26) of the first silicon-containing film (25) is suppressed from becoming concave, and, for example, when CMP treatment is performed, the accumulation of abrasive material is prevented. Furthermore, for example, in a configuration having a second concave portion in the transverse direction, the formation of a depression in the first silicon-containing film (25) is suppressed, thereby preventing the formation of a void when the first concave portion is embedded in the subsequent process.

[0062] In step S105, the substrate (W) is exposed to a plasma generated from a second treatment gas containing a first silicon-containing gas and a second silicon-containing gas to form a second fluid film (30) on the substrate (W).

[0063] Here, the control device (600) controls the conveying mechanism (106), etc., to convey the substrate (W) from the processing device (102) to the substrate support of the processing device (103). The control device (600) controls the gas supply unit, plasma generation unit, etc., of the processing device (103) to generate plasma of the second processing gas.

[0064] The first silicon-containing gas of the second treatment gas is the same gas as the first silicon-containing gas of the first treatment gas. Additionally, the second silicon-containing gas of the second treatment gas is the same gas as the second silicon-containing gas of the first treatment gas.

[0065] Here, the second treatment gas used in step S105 has a lower ratio of the second silicon-containing gas (crosslinking gas) compared to the first treatment gas used in step S102. That is, the ratio of the second silicon-containing gas (crosslinking gas) to the second treatment gas is lower than the ratio of the second silicon-containing gas (crosslinking gas) to the first treatment gas. Specifically, it is preferable that the ratio of the second silicon-containing gas (crosslinking gas) to the second treatment gas be within the range of 0.0385 to 0.074.

[0066] In the processing of step S105, the processing temperature of the substrate (W) is preferably within the range of, for example, 20℃ to 100℃. In addition, the processing temperature of the substrate (W) is more preferably within the range of, for example, 25℃ to 50℃.

[0067] FIG. 10 is an example of a chemical reaction equation describing the treatment of step S105. As shown in FIG. 10, an organic silicon compound (first silicon-containing gas) and a silane (second silicon-containing gas) react, and the cross-linking reaction of the organic silicon compound (first silicon-containing gas) proceeds by the silane (second silicon-containing gas) to form a fluid oligomer. Here, the ratio of the cross-linking gas (second silicon-containing gas) in the second treatment gas is lower compared to the first treatment gas, so the number of molecules of the fluid oligomer formed decreases. Accordingly, a second fluid membrane (30) having a second viscosity is formed. For reference, the second viscosity has a lower viscosity than the first viscosity.

[0068] FIG. 6 is an example of a cross-sectional schematic diagram of a substrate (W) after processing in step S105. A low-viscosity fluid oligomer is generated by a plasma produced from a second processing gas, and the fluid oligomer is filled into the second fluid film (30) by flowing into the concave portion (11) and the void (27) of the first silicon-containing film (25).

[0069] In step S106, an annealing treatment is performed. The second fluid film (30) is solidified by the annealing treatment. The solidified film becomes the second silicon-containing film (35). That is, the second silicon-containing film (35) is formed by the annealing treatment.

[0070] Here, the control device (600) controls the conveying mechanism (106), etc., to convey the substrate (W) from the processing device (103) to the substrate support of the processing device (104). The control device (600) controls the gas supply unit, heating unit, etc., of the processing device (104) to heat the substrate (W) in an inert gas (Ar gas) environment, thereby performing an annealing treatment on the substrate (W). For reference, the annealing treatment of step S106 may be omitted.

[0071] In the processing of step S106, the processing temperature of the substrate (W) is preferably within the range of, for example, 400℃ to 600℃. In addition, the processing temperature of the substrate (W) is more preferably within the range of, for example, 450℃ to 550℃.

[0072] In step S107, a plasma generated from the second reforming gas is exposed to the substrate (W) to reform the second silicon-containing film (35), thereby forming a reformed second silicon-containing film (35). Specifically, the second silicon-containing film (35) is densified.

[0073] Here, the control device (600) controls the gas supply unit, plasma generation unit, etc. of the processing device (104) to generate plasma of the second reformed gas.

[0074] The second reforming gas includes an inert gas (Ar gas) and hydrogen (H2) gas.

[0075] Here, the second reforming gas used in step S107 has a higher proportion of hydrogen (H2) gas compared to the first reforming gas used in step S104. That is, the ratio of hydrogen (H2) gas to the second reforming gas is greater than the ratio of hydrogen (H2) gas to the first reforming gas.

[0076] Additionally, the pressure inside the processing vessel in step S107 is higher than the pressure inside the processing vessel in step S104.

[0077] Additionally, the frequency of the high-frequency power supplied when generating plasma in step S107 is a higher frequency compared to the frequency of the high-frequency power supplied when generating plasma in step S104. The processing device (104) has, for example, a VHF plasma source as a plasma generating unit. It is preferable that the frequency of the high-frequency power supplied when generating plasma in step S107 be in the VHF range. Specifically, it is preferable that the frequency of the high-frequency power supplied when generating plasma in step S107 be within the range of 60 MHz to 300 MHz (for example, 180 MHz).

[0078] FIG. 11 is an example of a chemical reaction equation describing the processing of steps S106 and S107. As shown in FIG. 11, the fluid oligomer of the second fluid membrane (30) undergoes a cross-linking reaction by annealing treatment to form a SiO film (SiOC film, SiOCN film) of the second silicon-containing membrane (35). In addition, the SiO film (SiOC film, SiOCN film) of the second silicon-containing membrane (35) is densified by the plasma of the second reforming gas.

[0079] FIG. 7 is an example of a cross-sectional schematic diagram of a substrate (W) after processing steps S106 and S107. As shown in FIG. 7, a second silicon-containing film (35) is formed in the void (27). Accordingly, a third silicon-containing film (40) is formed by the first silicon-containing film (25) and the second silicon-containing film (35).

[0080] Additionally, after the processing of step S107, the processing of steps S105 to S107 may be repeated. Accordingly, the second silicon-containing film (35) can be embedded in the voids remaining in the third silicon-containing film (40).

[0081] Then, the control device (600) controls the conveying mechanism (106, 402), etc., to convey the substrate (W) from the processing device (104) to the carrier (C) through the load lock chambers (301~303). Accordingly, the processing shown in FIG. 2 is completed. In this way, the processing of steps S102~S107 is carried out continuously under a vacuum environment.

[0082] Here, the characteristics of the fluid films (first fluid film (20), second fluid film (30)) formed in steps S102 and S105 are further explained. FIG. 12 is an example of a diagram showing the relationship between the ratio of crosslinking gas and the viscosity of the fluid film. In FIG. 12 (a), a fluid film (20, 30) is formed on a substrate (W) having a concave portion (11). At this time, when the film thickness of the fluid film (20, 30) formed on the upper surface (12) of the base (10) is set to a predetermined film thickness (T0) (100 nm), the fluidity of the fluid film (20, 30) is evaluated by the film thickness (T) of the fluid film (20, 30) formed from the bottom surface (or bottom surface) of the concave portion (11). The thicker the film thickness (T), the lower the viscosity, and the thinner the film thickness (T), the higher the viscosity.

[0083] In FIG. 12 (b), the film thickness (T) of the fluid film formed from the bottom surface of the concave portion (11) was measured for cases where the flow rate ratio of the first silicon-containing gas (organic silicon compound gas) and the second silicon-containing gas (silane gas) was (1) 1:1, (2) 1:2, and (3) 1:5.

[0084] As shown in the results of Figure 12, it can be seen that as the ratio of the second silicon-containing gas (silane gas) to the first silicon-containing gas (organic silicon compound gas) decreases, the film thickness (T) becomes thicker. From this, it was found that the viscosity (fluidity) of the fluid film can be controlled by controlling the flow rate ratio of the first silicon-containing gas (organic silicon-containing gas) and the second silicon-containing gas (silane gas).

[0085] As described above, in the treatment of step S102 (the treatment for forming the first fluid film (20)), the first fluid film (20) of high viscosity (first viscosity) is embedded within the concave portion (11) by increasing the ratio of crosslinking molecules (second silicon-containing gas) in the first treatment gas. Accordingly, the influence of changes in film thickness during the annealing treatment and modification treatment (S103, S104) is reduced, and a void (27) can be formed in the first silicon-containing film (25). In addition, the formation of a depression on the upper surface (26) of the first silicon-containing film (25) can be suppressed. Furthermore, in a configuration having a second concave portion in the transverse direction, the formation of a depression in the first silicon-containing film (25) can be suppressed, thereby preventing the formation of a void when embedding in the first concave portion is performed in the next process.

[0086] Meanwhile, in the treatment of step S105 (treatment for forming the second fluid film (30)), by lowering the ratio of the crosslinking molecule (second silicon-containing gas) in the second treatment gas, the second fluid film (30) of low viscosity (second viscosity) can be embedded in the concave portion (11) and the void (27) of the first silicon-containing film (25).

[0087] For reference, the processing of step S103 (first annealing process) and the processing of step S106 (second annealing process) may be under the same processing conditions.

[0088] In addition, the plasma generation conditions of step S104 (first reforming process) and step S107 (second reforming process) differ, such as the ratio of inert gas (Ar gas) to hydrogen (H2) gas, the pressure inside the processing vessel, and the frequency of the high-frequency power supplied when generating plasma.

[0089] In the treatment of step S104 (first modification treatment), compared to the treatment of step S107 (second modification treatment), ions of the inert gas (Ar gas) generated by plasma are incident more frequently on the upper surface (26) or the surface (back surface) of the first silicon-containing film (25). Accordingly, solidification of the upper surface (26) or the surface (back surface) of the first silicon-containing film (25) is promoted. Accordingly, shrinkage of the surface of the first silicon-containing film (25) can be suppressed. In addition, the formation of a depression on the upper surface (26) of the first silicon-containing film (25) can be further suppressed.

[0090] In addition, in the treatment of step S107 (second modification treatment), the amount of hydrogen radicals generated by plasma is increased compared to the treatment of step S104 (first modification treatment). Accordingly, the third silicon-containing film (40) (first silicon-containing film (25), second silicon-containing film (35)) can be treated (modified) to a deeper part.

[0091] For reference, in the first treatment gas and the second treatment gas, by changing the ratio of the first silicon-containing gas to the second silicon-containing gas, the dielectric constant of the first silicon-containing film (25) formed from the first fluidized film (20) and the dielectric constant of the second silicon-containing film (35) formed from the second fluidized film (30) may be changed. Accordingly, the configuration may be such that the dielectric constant of the third silicon-containing film (40) embedded in the concave portion (11) is adjusted.

[0092] Although a substrate processing method for embedding a silicon-containing film within a concave portion has been described above, the present disclosure is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure as described in the claims.

[0093] The present invention claims priority based on patent application No. 2025-017153 filed with the Japan Patent Office on February 4, 2025, and incorporates herein by reference the entire contents thereof.

Claims

Claim 1 A substrate processing method for filling a concave area with a silicon-containing film, comprising: (a) a process of exposing a substrate to a plasma generated from a first processing gas comprising a first silicon-containing gas and a second silicon-containing gas different from the first silicon-containing gas to form a first fluid film having a first viscosity within the concave area; (b) a process of exposing the substrate to a plasma generated from a first modifying gas to modify the first fluid film to form a first silicon-containing film having pores; (c) a process of exposing the substrate to a plasma generated from a second processing gas comprising the first silicon-containing gas and the second silicon-containing gas to form a second fluid film having a second viscosity lower than the first viscosity within the concave area and within the pores of the first silicon-containing film; and (d) a process of exposing the substrate to a plasma generated from a second modifying gas to modify the second fluid film to form a second silicon-containing film. Claim 2 A substrate processing method according to claim 1, wherein the ratio of the second silicon-containing gas in the first processing gas of process (a) is greater than the ratio of the second silicon-containing gas in the second processing gas of process (c). Claim 3 A substrate processing method according to claim 2, wherein the ratio of the second silicon-containing gas to the first processing gas of process (a) is in the range of 0.29 to 0.375, and the ratio of the second silicon-containing gas to the second processing gas of process (c) is in the range of 0.0385 to 0.

074. Claim 4 A substrate processing method according to claim 1, wherein the processing pressure of process (b) is lower than the processing pressure of process (d). Claim 5 A substrate processing method according to claim 1, wherein the first reforming gas and the second reforming gas comprise an inert gas and a hydrogen gas. Claim 6 A substrate processing method according to claim 5, wherein the ratio of hydrogen gas to the second reforming gas in process (d) is greater than the ratio of hydrogen gas to the first reforming gas in process (b). Claim 7 A substrate processing method according to claim 1, wherein the processing temperature of process (a) is lower than the processing temperature of process (b), and the processing temperature of process (c) is lower than the processing temperature of process (d). Claim 8 A substrate processing method according to claim 1, wherein the processing temperature of process (a) and process (c) is within the range of 20℃ to 100℃, and the processing temperature of process (b) and process (d) is within the range of 400℃ to 600℃. Claim 9 A substrate processing method according to claim 1, wherein the above process (c) and the above process (d) are repeated. Claim 10 A substrate treatment method according to claim 1, wherein the process (b) comprises an annealing treatment of the first fluid film and a treatment of exposing the annealed first fluid film to a plasma of the first modified gas. Claim 11 A substrate treatment method according to claim 1, wherein the process (d) comprises an annealing treatment of the second fluid film and a treatment of exposing the annealed second fluid film to a plasma of the second modified gas. Claim 12 A substrate treatment method according to claim 1, wherein the first silicon-containing gas is an organic silicon compound. Claim 13 In claim 1, the second silicon-containing gas is Si n H 2n+2 A substrate processing method comprising a silicon-containing gas represented by (n is an integer greater than or equal to 1). Claim 14 A substrate processing method according to claim 1, wherein the above process (a), the above process (b), the above process (c), and the above process (d) are carried out continuously under a vacuum environment. Claim 15 A substrate processing method according to claim 1, wherein the frequency of the high-frequency power supplied when generating the plasma of process (d) is higher than the frequency of the high-frequency power supplied when generating the plasma of process (b). Claim 16 A substrate processing method according to claim 15, wherein the frequency of the high-frequency power supplied when generating the plasma in process (b) is in the HF band, and the frequency of the high-frequency power supplied when generating the plasma in process (d) is in the VHF band. Claim 17 A substrate processing method according to claim 1, wherein the above process (a) and the above process (c) are carried out within the same processing vessel. Claim 18 A substrate processing method according to claim 1, wherein the first silicon-containing film and the second silicon-containing film are any one of a SiO film, a SiOC film, or a SiOCN film. Claim 19 A substrate processing system for filling a concave area with a silicon-containing film, comprising: a first processing device that forms a first fluid film having a first viscosity within the concave area by exposing the substrate to a plasma generated from a first processing gas comprising a first silicon-containing gas and a second silicon-containing gas different from the first silicon-containing gas; a second processing device that forms a first silicon-containing film by exposing the substrate to a plasma generated from a first reforming gas to reform the first fluid film; a third processing device that forms a second fluid film having a second viscosity lower than the first viscosity by exposing the substrate to a plasma generated from a second processing gas comprising the first silicon-containing gas and a second silicon-containing gas different from the first silicon-containing gas; a fourth processing device that forms a second silicon-containing film by exposing the substrate to a plasma generated from a second reforming gas to reform the second fluid film; and a vacuum transport chamber connected to the first to fourth processing devices. A substrate processing system equipped with

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