Deposition method and deposition device

Abstract

To provide a technique for selectively forming an objective film containing silicon (Si) and oxygen (O) to a desired region.SOLUTION: A deposition method includes the following steps (A) to (C): a step (A) of preparing a substrate in which a first region where an insulation film is exposed and a second region where a conductive film is exposed are provided onto a front surface; a step (B) of selectively forming a catalyst layer for promoting a formation of an objective film containing silicon (Si) and oxygen (O) to a specific region that is separated from a boundary of a first region and a second region in the first region from the first and second regions; a step (C) of growing the objective film from the specific region to the boundary by supplying a precursor gas containing a silanol group (a SiOH group) to the front surface of the substrate after the step (B).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a film forming method and a film forming apparatus.

Background Art

[0002] The film forming method described in Patent Document 1 includes exposing a heated substrate to silanol vapor to form a silica layer on a specific region of the substrate. The specific region where the silica layer is formed is a region containing a metal or metalloid compound having Lewis acid characteristics.

[0003] The film forming method described in Patent Document 2 includes selectively forming a polyimide film or a self-assembled monolayer on the surface of a dielectric film with respect to the surface of a metal film, and selectively forming a silicon oxide film on the surface of a dielectric film with respect to the surface of a metal film, in this order. The silicon oxide film is formed using a metal catalyst and silanol.

[0004] The film forming method described in Patent Document 3 includes forming a metal-containing catalyst layer on the surface of a metal-containing oxide layer covering the surface of a metal film and on the surface of a dielectric film, removing the metal-containing oxide layer to remove the metal-containing catalyst layer on the metal-containing oxide layer, and forming a SiO 2 film on the remaining metal-containing catalyst layer on the surface of the derivative film.

[0005] The film forming method described in Patent Document 4 includes supplying a metal-containing catalyst gas to the substrate surface, supplying hydrogen radicals to the substrate surface, and supplying a silicon precursor gas containing silanol to the substrate surface.

[0006] The film forming method described in Patent Document 5 includes selectively forming a passivation film on the surface of a dielectric film with respect to the surface of a metal film, and selectively forming a target film on the surface of a dielectric film with respect to the surface of a metal film, in this order. The target film is an oxide film or a nitride film.

[0007] The film-forming method described in Patent Document 6 involves selectively forming a Ru film on the surface of a conductive film with respect to the surface of an insulating film. The Ru film is formed by alternately supplying Ru(EtCp) 2 gas and O 2 gas to the substrate surface. The surface of the insulating film has OH groups, and since the OH groups inhibit the adsorption of Ru(EtCp) 2 gas, the Ru film is selectively formed on the surface of the conductive film.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0009] One aspect of the present disclosure provides a technique for forming a target film containing silicon (Si) and oxygen (O) in a desired region.

Means for Solving the Problems

[0010] The film formation method according to one aspect of the present disclosure has the following (A) to (C). (A) Prepare a substrate having, on its surface, a first region where an insulating film is exposed and a second region where a conductive film is exposed. (B) Selectively form a catalyst layer that promotes the formation of a target film containing silicon (Si) and oxygen (O) in a specific region of the first region, which is away from the boundary between the first region and the second region, among the first region and the second region. (C) After (B), supply a precursor gas containing a silanol group (SiOH group) to the surface of the substrate, thereby growing the target film from the specific region toward the boundary.

Effects of the Invention

[0011] According to one aspect of the present disclosure, a target film containing silicon (Si) and oxygen (O) can be formed in a desired region.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same reference numerals, and the description thereof may be omitted.

[0014] Mainly referring to FIGS. 1 to 2, a film forming method according to an embodiment will be described. The film forming method has, for example, steps S101 to S104 shown in FIG. 1. Note that the film forming method does not necessarily have all of the steps S101 to S104 shown in FIG. 1, and for example, may not have step S103. Further, the film forming method may have steps other than steps S101 to S104 shown in FIG. 1.

[0015] Step S101 has, as shown in FIG. 2, preparing a substrate 1. The substrate 1 has a base substrate 10. The base substrate 10 is, for example, a silicon wafer, a compound semiconductor wafer, or a glass substrate. The substrate 1 has a first region A1 where the insulating film 11 is exposed and a second region A2 where the conductive film 12 is exposed on the substrate surface 1a. The substrate surface 1a is, for example, the upper surface of the substrate 1. The insulating film 11 and the conductive film 12 are formed on the base substrate 10. A functional film (not shown) may be formed between the base substrate 10 and the insulating film 11 or between the base substrate 10 and the conductive film 12.

[0016] The insulating film 11 is, for example, an interlayer insulating film. The interlayer insulating film is preferably a low dielectric constant (Low-k) film. The insulating film 11 is not particularly limited, but is, for example, a SiO film, a SiN film, a SiOC film, a SiON film, or a SiOCN film. Here, the SiO film means a film containing silicon (Si) and oxygen (O). The atomic ratio of silicon (Si) to oxygen (O) in the SiO film is usually 1:2, but is not limited to 1:2. The same applies to the SiN film, the SiOC film, the SiON film, and the SiOCN film in that they contain each element, and the stoichiometric ratio is not limited. The insulating film 11 has recesses on the substrate surface 1a. The recesses are trenches, contact holes, or via holes.

[0017] The conductive film 12 is filled in the recesses of the insulating film 11, for example. The conductive film 12 is, for example, a metal film. The metal film is, for example, a Cu film, a Co film, a Ru film, a W film, or a Mo film. Note that the conductive film 12 may be a cap film. That is, as shown in FIG. 4, a second conductive film 15 may be embedded in the recesses of the insulating film 11, and the conductive film 12 may cover the second conductive film 15. The second conductive film 15 is formed of a metal different from that of the conductive film 12. For example, the second conductive film 15 is a Cu film and the conductive film 12 (cap film) is a Co film or a Ru film. Also, the surface of the conductive film 12 and the surface of the insulating film 11 do not have to be flush with each other and may have a step.

[0018] The substrate surface 1a may have a region where the barrier film 13 is exposed at the boundary between the first region A1 and the second region A2. The barrier film 13 is formed between the insulating film 11 and the conductive film 12 and suppresses metal diffusion from the conductive film 12 to the insulating film 11. The barrier film 13 is not particularly limited, but is, for example, a TaN film or a TiN film. Here, the TiN film means a film containing titanium (Ti) and nitrogen (N). The atomic ratio of Ti to N in the TiN film is usually 1:1, but is not limited to 1:1. The same applies to the TaN film in that it contains each element, and the stoichiometric ratio is not limited.

[0019] As shown in FIGS. 3 and 4, the surface 1a of the substrate may have a region where the liner film 14 is exposed at the boundary between the first region A1 and the second region A2. The liner film 14 is formed between the conductive film 12 and the barrier film 13. The liner film 14 is formed on the barrier film 13 and assists in the formation of the conductive film 12. The conductive film 12 is formed on the liner film 14. For example, the conductive film 12 is a Cu film and the liner film 14 is a Co film or a Ru film.

[0020] As shown in FIG. 2, step S102 includes selectively forming the catalyst layer 17 in a specific region A3 of the first region A1 among the first region A1 and the second region A2. The specific region A3 of the first region A1 is a region away from the boundary between the first region A1 and the second region A2. Although the catalyst layer 17 will be described in detail later, for example, after being formed over the entire surface 1a of the substrate, it can be left only in the specific region A3 by removing the regions other than the specific region A3.

[0021] The catalyst layer 17 is formed, for example, using a metal catalyst-containing gas. The metal catalyst-containing gas contains a metal catalyst. The metal catalyst-containing gas is preferably an organometallic compound gas. Specifically, an organoaluminum compound gas and an organotitanium compound gas can be mentioned. Examples of the organoaluminum compound gas include trimethylaluminum (TMA) gas, triethylaluminum (TEA) gas, dimethylaluminum chloride gas, or dimethylaluminum isopropoxide (DMAI). Examples of the organotitanium compound gas include tetrakis(dimethylamino)titanium (TDMAT) gas.

[0022] In this embodiment, the catalyst layer 17 is formed using only the metal catalyst-containing gas and contains only the metal catalyst. However, the metal catalyst may be oxidized with an oxidizing gas, or may contain oxygen (O) in addition to the metal catalyst. That is, the catalyst layer 17 may be a metal oxide layer. By oxidizing the metal catalyst, the desorption or diffusion of the metal catalyst can be suppressed. The oxidizing gas is, for example, H 2 O gas, O 2 gas or O 3 gas or the like.

[0023] Step S103 includes activating the catalyst layer 17 by supplying a plasmaized gas to the surface 1a of the substrate on which the catalyst layer 17 is formed. The gas to be plasmaized is hydrogen gas in this embodiment, but is not limited to hydrogen gas, and may be a noble gas or a mixed gas of hydrogen gas and a noble gas. The noble gas is, for example, Ar gas or He gas. The gas to be plasmaized in step S103 preferably does not contain an oxygen-based gas in order to suppress the oxidation of the conductive film 12. The activation of the catalyst layer 17 is particularly effective when the catalyst layer 17 is a metal oxide layer.

[0024] An example of the processing conditions of step S103 is shown below. H 2 gas flow rate: 200 sccm to 3000 sccm Ar gas flow rate: 0 sccm to 6000 sccm H 2 The ratio of H 2 gas in the mixed gas of H gas and Ar gas: 0 vol% to 100 vol% Power frequency for plasma generation: 10 MHz to 60 MHz Power for plasma generation: 50 W to 600 W Processing time: 2 sec to 120 sec Processing temperature: 80°C to 350°C

[0025] As shown in FIG. 2, in step S104, a precursor gas is supplied to the substrate surface 1a to grow the target film 16 from the specific region A3 toward the boundary between the first region A1 and the second region A2. The precursor gas contains a silanol group (SiOH group). The catalyst layer 17 promotes the formation of the target film 16 by promoting the dehydration condensation reaction of the silanol group. The target film 16 is preferably formed over the entire first region A1. However, it is preferable that the target film 16 does not protrude into the second region A2.

[0026] The silanol group-containing gas used as the precursor gas is not particularly limited. For example, tris(tert-pentoxy)silanol (TPSOL), triethylsilanol, methyl bis(tert-pentoxy)silanol, or tris(tert-butoxy)silanol (TBSOL) is used.

[0027] An example of the processing conditions in step S104 is shown below. Flow rate of TPSOL gas: 0.1 g / min to 0.5 g / min Processing time: 3 seconds to 300 seconds Processing temperature: 80°C to 350°C Processing pressure: 133 Pa to 1200 Pa.

[0028] According to the present embodiment, before step S104, the catalyst layer 17 that promotes the growth of the target film 16 is formed in a narrowed manner in the specific region A3 of the first region A1. Therefore, even if the target film 16 grows from the specific region A3 toward the second region A2 in step S104, it is possible to suppress the target film 16 from protruding into the second region A2. Thus, the target film 16 can be formed in a desired region (for example, the first region A1). When the target film 16 has insulating properties, it is possible to suppress the opening width of the insulating target film 16 from becoming narrow, and when forming a via wiring in the second region A2, it is possible to suppress the resistance of the via from increasing.

[0029] Next, with reference to FIGS. 5 to 6, a first example of step S102 shown in FIG. 1 will be described. Step S102 has, for example, steps S102a to S102c shown in FIGS. 5 and 6. Note that step S102 does not necessarily have all of steps S102a to S102c shown in FIGS. 5 and 6. Further, step S102 may have steps other than steps S102a to S102c shown in FIGS. 5 and 6.

[0030] As shown in FIG. 6, step S102a includes forming a sacrificial film 18 on at least a region excluding a specific region A3 of the first region A1 and the entire second region A2. The sacrificial film 18 is selectively formed on the second region A2 among the first region A1 and the second region A2, although details will be described later. However, the selectivity is not perfect, and the sacrificial film 18 is formed so as to protrude from the second region A2 to the first region A1. The sacrificial film 18 is preferably formed on the entire surface 1a of the substrate excluding the specific region A3.

[0031] As shown in FIG. 6, step S102b includes forming a catalyst layer 17 on the first region A1 and the second region A2. In the present embodiment, the catalyst layer 17 is formed using only a metal catalyst-containing gas and contains only a metal catalyst, but the metal catalyst may be oxidized with an oxidizing gas or may contain oxygen (O) in addition to the metal catalyst. That is, the catalyst layer 17 may be a metal oxide layer. The catalyst layer 17 is preferably formed on the entire surface 1a of the substrate.

[0032] The sacrificial film 18 may be an inhibiting film that inhibits the formation of the catalyst layer 17, although details will be described later. Therefore, the density of the catalyst layer 17 may be different between the specific region A3 where the inhibiting film is not formed and the region other than the specific region A3 where the inhibiting film is formed. The catalyst layer 17 may be densely formed in the specific region A3 and sparsely formed in the region other than the specific region A3. Since only the catalyst layer 17 needs to remain in the specific region A3 at the completion of step S102, the catalyst layer 17 may be sparsely formed in the region other than the specific region A3.

[0033] Step S102c, as shown in FIG. 6, involves removing the sacrificial film 18 and selectively leaving the catalyst layer 17 in a specific region A3. By removing the sacrificial film 18, the catalyst layer 17 deposited on the sacrificial film 18 can be removed. The method for removing the sacrificial film 18 is appropriately selected according to the type of the sacrificial film 18. For example, when the sacrificial film 18 is a self-assembled monolayer, the self-assembled monolayer is decomposed and removed by supplying a plasma gas to the substrate surface 1a. Also, when the sacrificial film 18 is a metal film, the metal film is altered into a volatile substance and removed by supplying ClF 3 gas or O 3 gas to the substrate surface 1a.

[0034] Next, with reference to FIG. 7, a first example of step S102a shown in FIGS. 5 and 6 will be described. In the first example of step S102a, the sacrificial film 18 is a self-assembled monolayer 18A. Hereinafter, the self-assembled monolayer (Self-Assembled Monolayer: SAM) 18A may be referred to as SAM18A. The first example of step S102a, as shown in FIG. 7, includes applying an organic compound, which is a raw material of SAM18A, in a liquid L state to the substrate surface 1a (step S102a1) and drying the applied liquid L (step S102a2).

[0035] The organic compound is not particularly limited, but includes, for example, thiol-based compounds. Specific examples of thiol-based compounds include CF 3 (CF 2 ) 5 CH 2 CH 2 SH (1H,1H,2H,2H-perfluorooctanethiol: PFOT), CH 3 (CH 2 ) 5 SH (hexanethiol: HT), and CH 3 (CH 2 ) 17SH (octadecanethiol) is mentioned. Thiol-based compounds are more likely to chemisorb on the surface of the conductive film 12 than on the surface of the insulating film 11. Therefore, the SAM 18A is selectively formed in the second region A2 out of the first region A1 and the second region A2. However, the selectivity is not perfect, and the SAM 18A is formed so as to protrude from the second region A2 to the first region A1.

[0036] The organic compound is not limited to thiol-based compounds. The organic compound may include phosphonic acid-based compounds, carboxylic acid-based compounds, or nitro-based compounds. Note that the organic compound may include olefin-based compounds or organosilane-based compounds. The olefin-based compound is represented by the general formula "R-CH=CH 2 ". The organosilane-based compound is, for example, trichlorosilane-based, methoxysilane-based, or ethoxysilane-based. The trichlorosilane-based organic compound is represented by the general formula "R-SiCl 3 ". The methoxysilane-based organic compound is represented by the general formula "R-Si(OCH 3 ) 3 ". The ethoxysilane-based organic compound is represented by the general formula "R-Si(OCH 2 CH 3 ) 3 ".

[0037] As described above, the organic compound is applied in the state of the liquid L. The liquid L is applied to the entire surface of the substrate surface 1a. In this embodiment, the application method of the liquid L is the spin coating method, but it may be a dip coating method, a die coating method, or the like, and is not particularly limited. The organic compound is used by being dissolved in an organic solvent. The organic solvent is, for example, IPA (isopropyl alcohol). The concentration of the organic compound in the liquid L is, for example, 0.1 volume% to 10 volume%. The liquid L can supply a large amount of the organic compound to the substrate surface 1a compared to a gas. Therefore, the SAM 18 is likely to protrude from the second region A2 to the first region A1.

[0038] The drying of the liquid L includes heating the substrate 1. It is preferable to increase the heating temperature of the substrate 1 stepwise. The heating temperature of the substrate 1 preferably includes a temperature equal to or higher than the boiling point of the organic solvent. When the substrate 1 is heated, the organic solvent vaporizes. In this process, among the first region A1 and the second region A2, the liquid L selectively accumulates in the second region A2. The liquid L forms a convex curved surface upward due to surface tension. The liquid L has a height and spread corresponding to the surface tension and protrudes from the second region A2. Therefore, SAM18A is formed protruding from the second region A2 to the first region A1.

[0039] Note that step S102a may include cleaning the substrate surface 1a with a chemical solution or pure water before applying the liquid L. Thereby, foreign matters can be removed. Also, step S102a may include supplying an organic solvent to the substrate surface 1a and dissolving and removing unreacted organic compounds from the substrate surface 1a after drying the applied liquid L. Note that since SAM18A is chemically adsorbed by reacting with the substrate surface 1a, it is difficult to dissolve in the organic solvent and remains on the substrate surface 1a.

[0040] Specific examples of steps S102a1 and S102a2 are as follows. First, with the substrate 1 vacuum-adsorbed by a spin chuck, while rotating the substrate 1, a thiol-based compound-containing solution with IPA or the like as a solution is dropped onto the center of the substrate surface 1a. The rotation of the substrate 1 is continued at the same rotation speed as when dropping or at a higher rotation speed, and the unreacted thiol-based compound-containing solution is shaken off from the substrate surface 1a. At the portion where the thiol-based compound on the substrate surface 1a has reacted, the solvent IPA is vaporized. Next, the substrate 1 is heated to further promote the vaporization of IPA. Thereafter, with the substrate 1 again vacuum-adsorbed by a spin chuck, while rotating the substrate 1, an organic solvent such as IPA is dropped onto the center of the substrate surface 1a to further proceed with the removal of unreacted organic compounds. Thereafter, the substrate 1 is heated again to vaporize and remove the organic solvent such as IPA, and to strengthen the reaction between the substrate surface 1a and the thiol-based compound to improve the hydrophobicity of SAM18A.

[0041] An example of the processing conditions for steps S102a1 and S102a2 is shown below. Rotation speed at the time of solution dropping: 100 to 3000 rpm Solution dropping time: 3 seconds to 120 seconds Substrate heating temperature: 80°C to 350°C Substrate heating time: 30 seconds to 1800 seconds.

[0042] When the sacrificial film 18 is SAM18A, SAM18A functions as an inhibitory film that inhibits the formation of the catalyst layer 17 in step S102b. Therefore, in step S102b, the catalyst layer 17 is densely formed in the specific region A3, and the catalyst layer 17 is sparsely formed in the regions other than the specific region A3. Note that in the regions other than the specific region A3, although the catalyst layer 17 is hardly formed in this embodiment, it is not necessary for the catalyst layer 17 to be not formed at all.

[0043] When the sacrificial film 18 is SAM18A, step S102c decomposes and removes SAM18A by supplying a plasma gas to the substrate surface 1a. The gas to be plasmaized is the same gas as in step S103. Therefore, step S102c can also serve as step S103 (activation of the catalyst layer 17).

[0044] Next, with reference to FIG. 8, a second example of step S102a shown in FIGS. 5 and 6 will be described. In the second example of step S102a, the sacrificial film 18 is a metal film 18B. The metal film 18B is excellent in that it does not reduce the resistance of the via during via formation even if it remains without being completely removed from the second region A2 in step S102c.

[0045] As shown in FIG. 8, the second example of step S102a includes forming the metal film 18B so as to protrude from the second region A2 to the first region A1 by supplying a metal-containing gas that selectively adsorbs to the conductive film 12 out of the insulating film 11 and the conductive film 12 to the substrate surface 1a (step S102a3).

[0046] The metal film 18B preferably contains one or more elements selected from Ru, W, and Mo, and more preferably is a Ru film. The Ru film is formed by alternately supplying Ru(EtCp) 2 gas and O 2 gas to the substrate surface 1a. The surface of the insulating film 11 has OH groups, and the OH groups inhibit the adsorption of Ru(EtCp) 2 gas. Ru(EtCp) 2 gas adsorbs on the surface without OH groups without adsorbing on the surface with OH groups. Therefore, the Ru film is selectively formed in the second region A2 among the first region A1 and the second region A2. However, the selectivity is not perfect, and the Ru film is formed so as to protrude from the second region A2 to the first region A1. As the film formation conditions of the Ru film, the film formation conditions described in Patent Document 6 can be used.

[0047] Ru(EtCp) 2 gas basically does not adsorb on the first region A1. However, if there are defects in the first region A1, Ru(EtCp) 2 gas will adsorb to the defects. Examples of the defects include metal remaining after polishing such as CMP or damage. Since Ru(EtCp) 2 gas adsorbs to the defects in the first region A1, metal grains 19 are also formed in an island shape in the first region A1. This metal grain 19 contains Ru.

[0048] Therefore, the second example of step S102a may have removing the metal grains 19 formed in the first region A1 with an etching gas (step S102a4) as shown in FIG. 8. As the etching gas, for example, ClF 3 gas or O 3 gas is used. Since the metal grains 19 are smaller than the metal film 18B, it is possible to remove the metal grains 19 while leaving the metal film 18B. As the etching conditions of the metal grains 19, the etching conditions described in Patent Document 6 can be used.

[0049] In addition, when the sacrificial film 18 is the metal film 18B, step S102c is the same as step S102a4, and ClF3 Gas or O 3 By supplying the ClF gas to the substrate surface 1a, the metal film 18B can be altered into a volatile substance and removed. 3 Gas and O 3 The gas does not remove the catalyst layer 17. Therefore, the catalyst layer 17 remains in the specific region A3. If the catalyst layer 17 does not completely cover the metal film 18B, the ClF gas or O gas can remove the metal film 18B. 3 Gas or O 3 gas can remove the metal film 18B.

[0050] Next, with reference to FIGS. 9 to 10, a second example of step S102 shown in FIG. 1 will be described. Step S102 has, for example, steps S102a' to S102c' shown in FIGS. 9 and 10. Note that step S102 does not necessarily have all of steps S102a' to S102c' shown in FIGS. 9 and 10. Further, step S102 may have steps other than steps S102a' to S102c' shown in FIGS. 9 and 10.

[0051] Step S102a' has, as shown in FIG. 10, selectively forming an inhibition film 21 that inhibits the formation of the catalyst layer 17 from the first region A1 to the second region A2. The inhibition film 21 is, for example, a self-assembled monolayer. The self-assembled monolayer is formed by supplying an organic compound such as a thiol-based compound to the substrate surface 1a in a gaseous state. When the organic compound is supplied in a gaseous state, the organic compound that has not adsorbed on the substrate 1 is exhausted without remaining on the substrate 1, so the self-assembled monolayer hardly protrudes from the first region A1 to the second region A2. Note that the inhibition film 21 is not limited to a self-assembled monolayer and may be, for example, a graphene-containing film. The inhibition film 21 is not formed on the exposed surface of the barrier film 13 in the present embodiment, but may be formed.

[0052] Step S102b' includes forming a catalyst layer 17 in the first region A1, as shown in Fig. 10. The catalyst layer 17 is formed using, for example, a metal catalyst-containing gas as described above. In this embodiment, the catalyst layer 17 is formed using only a metal catalyst-containing gas and contains only a metal catalyst, but the metal catalyst may be oxidized with an oxidizing gas, or oxygen (O) may be contained in addition to the metal catalyst. In other words, the catalyst layer 17 may be a metal oxide layer.

[0053] Step S102c' includes etching the end of the catalyst layer 17 facing the inhibitor film 21 using components of the inhibitor film 21 while decomposing the inhibitor film 21, as shown in Fig. 10. By using the components of the inhibitor film 21, the catalyst layer 17 can be etched only in the vicinity of the inhibitor film 21. The catalyst layer 17 is etched away from the boundary between the first region A1 and the second region A2. As a result, the catalyst layer 17 remains in the specific region A3 of the first region A1.

[0054] If the inhibition film 21 contains fluorine, step S102c' is 2 The method includes supplying a gas containing O to the substrate surface 1a. 2 Hydrofluoric acid is generated by the reaction between the gas containing O and the inhibition film 21. The generated hydrofluoric acid can etch unnecessary portions of the catalyst layer 17. The products generated by the etching are volatile and are removed by exhaust. 2 In order to suppress the generation of oxygen plasma, it is preferable that the O-containing gas is supplied to the substrate surface 1a without being converted into plasma, so that oxidation of the conductive film 12 can be suppressed.

[0055] Step S102c' is H 2 The gas containing O and the gas in plasma form may be alternately supplied to the substrate surface 1a. The gas in plasma form may be, for example, hydrogen gas, a rare gas, or a mixture of hydrogen gas and a rare gas. The gas in plasma form can decompose the inhibition film 21 and promote the generation of hydrofluoric acid. 2 By alternately supplying gas containing O and plasma gas, 2 There is no need to convert a gas containing O into plasma, and oxidation of the conductive film 12 can be suppressed.

[0056] An example of the processing conditions for step S102c' is shown below. <Process 1> H 2 Flow rate of O gas: 10 sccm to 500 sccm, Processing time: 0.1 sec to 120 sec, Processing temperature: 100 °C to 350 °C, Processing pressure: 50 Pa to 1200 Pa. <Process 2> H 2 Flow rate of H gas: 200 sccm to 3000 sccm, Flow rate of Ar gas: 100 sccm to 6000 sccm, H 2 Ratio of H gas in the mixed gas of H gas and Ar gas 2 Ratio of H gas: 20 vol% to 90 vol%, Power supply frequency for plasma generation: 10 MHz to 60 MHz, Power for plasma generation: 50 W to 600 W, Processing time: 2 sec to 120 sec, Processing temperature: 100 °C to 350 °C, Processing pressure: 50 Pa to 1200 Pa. <Number of repetitions of Process 1 and Process 2> 1 to 50 times.

[0057] Next, with reference to FIG. 11, a film forming apparatus 100 for implementing the above film forming method will be described. As shown in FIG. 11, the film forming apparatus 100 includes a first processing unit 200A, a second processing unit 200B, a third processing unit 200C, a transport unit 400, and a control unit 500. The first processing unit 200A implements step S102 of FIG. 1. The second processing unit 200B implements step S103 of FIG. 1. The third processing unit 200C implements step S104 of FIG. 1. The first processing unit 200A, the second processing unit 200B, and the third processing unit 200C may have the same structure or different structures. It is also possible to implement all of steps S102 to S104 of FIG. 1 only with the first processing unit 200A. The transport unit 400 transports the substrate 1 to the first processing unit 200A, the second processing unit 200B, and the third processing unit 200C. The control unit 500 controls the first processing unit 200A, the second processing unit 200B, the third processing unit 200C, and the transport unit 400.

[0058] The transport unit 400 includes a first transport chamber 401 and a first transport mechanism 402. The internal atmosphere of the first transport chamber 401 is an atmospheric atmosphere. The first transport mechanism 402 is provided inside the first transport chamber 401. The first transport mechanism 402 includes an arm 403 that holds the substrate 1 and travels along a rail 404. The rail 404 extends in the arrangement direction of the carriers C.

[0059] Further, the transport unit 400 includes a second transport chamber 411 and a second transport mechanism 412. The internal atmosphere of the second transport chamber 411 is a vacuum atmosphere. The second transport mechanism 412 is provided inside the second transport chamber 411. The second transport mechanism 412 includes an arm 413 that holds the substrate 1, and the arm 413 is arranged to be movable in the vertical and horizontal directions and rotatable around a vertical axis. The first processing unit 200A, the second processing unit 200B, and the third processing unit 200C are connected to the second transport chamber 411 via different gate valves G.

[0060] Furthermore, the transfer unit 400 has a load lock chamber 421 between the first transfer chamber 401 and the second transfer chamber 411. The internal atmosphere of the load lock chamber 421 can be switched between a vacuum atmosphere and an atmospheric atmosphere by a pressure regulating mechanism (not shown). Thereby, the inside of the second transfer chamber 411 can always be maintained in a vacuum atmosphere. Also, it is possible to suppress the inflow of gas from the first transfer chamber 401 into the second transfer chamber 411. Gate valves G are provided between the first transfer chamber 401 and the load lock chamber 421, and between the second transfer chamber 411 and the load lock chamber 421.

[0061] The control unit 500 is, for example, a computer and has an arithmetic unit 501 such as a CPU (Central Processing Unit) and a storage unit 502 such as a memory. A program for controlling various processes executed in the film forming apparatus 100 is stored in the storage unit 502. The control unit 500 controls the operation of the film forming apparatus 100 by causing the arithmetic unit 501 to execute the program stored in the storage unit 502. The control unit 500 controls the first processing unit 200A, the second processing unit 200B, the third processing unit 200C, and the transfer unit 400, and implements the above-described film forming method.

[0062] Next, the operation of the film forming apparatus 100 will be described. First, the first transfer mechanism 402 takes out the substrate 1 from the carrier C, transfers the taken-out substrate 1 to the load lock chamber 421, and exits from the load lock chamber 421. Next, the internal atmosphere of the load lock chamber 421 is switched from an atmospheric atmosphere to a vacuum atmosphere. Thereafter, the second transfer mechanism 412 takes out the substrate 1 from the load lock chamber 421 and transfers the taken-out substrate 1 to the first processing unit 200A.

[0063] Next, the first processing unit 200A implements step S102. Thereafter, the second transfer mechanism 412 takes out the substrate 1 from the first processing unit 200A and transfers the taken-out substrate 1 to the second processing unit 200B. During this time, the surrounding atmosphere of the substrate 1 can be maintained in a vacuum atmosphere, and contamination of the substrate 1 can be suppressed.

[0064] Next, the second processing unit 200B performs step S103. After that, the second transfer mechanism 412 takes out the substrate 1 from the second processing unit 200B and transfers the taken-out substrate 1 to the third processing unit 200C. During this period, the ambient atmosphere around the substrate 1 can be maintained as a vacuum atmosphere, and contamination of the substrate 1 can be suppressed.

[0065] Next, the third processing unit 200C performs step S104. After that, the second transfer mechanism 412 takes out the substrate 1 from the third processing unit 200C, transfers the taken-out substrate 1 to the load lock chamber 421, and exits from the load lock chamber 421. Subsequently, the internal atmosphere of the load lock chamber 421 is switched from a vacuum atmosphere to an atmospheric atmosphere. Then, the first transfer mechanism 402 takes out the substrate 1 from the load lock chamber 421 and accommodates the taken-out substrate 1 in the carrier C. And the processing of the substrate 1 is completed.

[0066] Next, referring to FIG. 12, the first processing unit 200A will be described. Note that since the second processing unit 200B and the third processing unit 200C are configured in the same manner as the first processing unit 200A, the illustration and description thereof are omitted.

[0067] The first processing unit 200A includes an airtight processing container 210 having a substantially cylindrical shape. An exhaust chamber 211 is provided at the center of the bottom wall of the processing container 210. The exhaust chamber 211 has, for example, a substantially cylindrical shape protruding downward. An exhaust pipe 212 is connected to the exhaust chamber 211, for example, on the side surface of the exhaust chamber 211.

[0068] An exhaust source 272 is connected to the exhaust pipe 212 via a pressure controller 271. The pressure controller 271 includes a pressure adjustment valve such as a butterfly valve. The exhaust pipe 212 is configured to be able to decompress the inside of the processing container 210 by the exhaust source 272. The pressure controller 271 and the exhaust source 272 constitute a gas discharge mechanism 270 for discharging the gas inside the processing container 210.

[0069] On the side surface of the processing container 210, a transfer port 215 is provided. The transfer port 215 is opened and closed by a gate valve G. The loading and unloading of the substrate 1 between the inside of the processing container 210 and the second transfer chamber 411 (see FIG. 11) are performed through the transfer port 215.

[0070] Inside the processing container 210, a stage 220, which is a holding part for holding the substrate 1, is provided. The stage 220 holds the substrate 1 horizontally with the substrate surface 1a facing upward. The stage 220 is formed in a substantially circular shape in plan view and is supported by a support member 221. On the surface of the stage 220, a substantially circular concave portion 222 for placing the substrate 1 with a diameter of, for example, 300 mm is formed. The concave portion 222 has an inner diameter slightly larger than the diameter of the substrate 1. The depth of the concave portion 222 is configured to be substantially the same as the thickness of the substrate 1, for example. The stage 220 is formed of a ceramic material such as aluminum nitride (AlN), for example. Also, the stage 220 may be formed of a metal material such as nickel (Ni). Note that instead of the concave portion 222, a guide ring for guiding the substrate 1 may be provided at the peripheral edge of the surface of the stage 220.

[0071] In the stage 220, a lower electrode 223 that is grounded, for example, is embedded. Below the lower electrode 223, a heating mechanism 224 is embedded. The heating mechanism 224 heats the substrate 1 placed on the stage 220 to a set temperature by being supplied with power from a power supply unit (not shown) based on a control signal from the control unit 500 (see FIG. 11). When the entire stage 220 is made of metal, the entire stage 220 functions as a lower electrode, so the lower electrode 223 does not need to be embedded in the stage 220. The stage 220 is provided with a plurality of (for example, three) lifting pins 231 for holding and lifting the substrate 1 placed on the stage 220. The material of the lifting pins 231 may be, for example, ceramics such as alumina (Al 2 O 3 ) or quartz. The lower end of the lifting pin 231 is attached to a support plate 232. The support plate 232 is connected to a lifting mechanism 234 provided outside the processing container 210 via a lifting shaft 233.

[0072] The elevating mechanism 234 is installed, for example, at the lower part of the exhaust chamber 211. The bellows 235 is provided between the opening 219 for the elevating shaft 233 formed on the lower surface of the exhaust chamber 211 and the elevating mechanism 234. The shape of the support plate 232 may be a shape that can be elevated without interfering with the support member 221 of the stage 220. The elevating pin 231 is configured to be vertically movable between above the surface of the stage 220 and below the surface of the stage 220 by the elevating mechanism 234.

[0073] The gas supply unit 240 is provided on the top wall 217 of the processing container 210 via an insulating member 218. The gas supply unit 240 forms the upper electrode and faces the lower electrode 223. A high-frequency power supply 252 is connected to the gas supply unit 240 via a matcher 251. By supplying high-frequency power of 450 kHz to 100 MHz from the high-frequency power supply 252 to the upper electrode (gas supply unit 240), a high-frequency electric field is generated between the upper electrode (gas supply unit 240) and the lower electrode 223, and capacitively coupled plasma is generated. The plasma generation unit 250 that generates plasma includes the matcher 251 and the high-frequency power supply 252. Note that the plasma generation unit 250 is not limited to capacitively coupled plasma and may generate other plasmas such as inductively coupled plasma. Note that in a process where plasma is not generated, it is not necessary for the gas supply unit 240 to form the upper electrode, and the lower electrode 223 is also not necessary.

[0074] The gas supply unit 240 includes a hollow gas supply chamber 241. A number of holes 242 for dispersedly supplying the processing gas into the processing container 210 are, for example, evenly arranged on the lower surface of the gas supply chamber 241. For example, above the gas supply chamber 241 in the gas supply unit 240, a heating mechanism 243 is embedded. The heating mechanism 243 is heated to a set temperature by being supplied with power from a power supply unit (not shown) based on a control signal from the control unit 500.

[0075] A gas supply mechanism 260 is connected to a gas supply chamber 241 via a gas supply passage 261. The gas supply mechanism 260 supplies a gas used in at least one of steps S102 to S104 in FIG. 1 to the gas supply chamber 241 via the gas supply passage 261. Although not shown, the gas supply mechanism 260 includes, for each type of gas, an individual pipe, an on-off valve provided in the middle of the individual pipe, and a flow controller provided in the middle of the individual pipe. When the on-off valve opens the individual pipe, gas is supplied from a supply source to the gas supply passage 261. The supply amount is controlled by the flow controller. On the other hand, when the on-off valve closes the individual pipe, the supply of gas from the supply source to the gas supply passage 261 is stopped.

[0076] As described above, embodiments of the film forming method and the film forming apparatus according to the present disclosure have been described, but the present disclosure is not limited to the above embodiments. Within the scope described in the claims, various changes, modifications, substitutions, additions, deletions, and combinations are possible. Naturally, they also belong to the technical scope of the present disclosure.

Description of Reference Numerals

[0077] 1 Substrate 1a Substrate surface 11 Insulating film 12 Conductive film 16 Target film 17 Catalyst layer A1 First region A2 Second region

Claims

1. (A) preparing a substrate having, on its surface, a first region where an insulating film is exposed and a second region where a conductive film is exposed; (B) forming, selectively in a specific region of the first region, which is away from the boundary between the first region and the second region among the first region and the second region, a catalyst layer that promotes the formation of a target film containing silicon (Si) and oxygen (O); (C) after (B), supplying a precursor gas containing a silanol group (SiOH group) to the surface of the substrate to grow the target film from the specific region toward the boundary; A film forming method comprising the above steps.

2. In the above (B), (Ba) forming an inhibitory film that inhibits the formation of the catalyst layer in a region excluding the specific region of the first region and the entire second region; (Bb) after (Ba), forming the catalyst layer in the specific region; (Bc) after (Bb), removing the inhibitory film and selectively leaving the catalyst layer in the specific region; The film forming method according to Claim 1, comprising the above steps.

3. The inhibitory film is a self-assembled monolayer, and (Ba) includes applying, in a liquid state, an organic compound that is a raw material of the self-assembled monolayer to the surface of the substrate and drying the applied liquid; (Bc) includes supplying a gas that has been made into plasma to the surface of the substrate. The film forming method according to Claim 2.

4. In the above (B), (Ba) forming a sacrificial film in a region excluding the specific region of the first region and the entire second region; (Bb) after (Ba), forming the catalyst layer in the first region and the second region; (Bc) after (Bb), removing the sacrificial film and selectively leaving the catalyst layer in the specific region; The film forming method according to Claim 1, comprising the above steps.

5. The sacrificial film is a metal film, and (Ba) includes supplying, to the surface of the substrate, a metal-containing gas that selectively adsorbs to the conductive film among the insulating film and the conductive film. The (Bc) supplies ClF ３ gas or O ３ gas to the surface of the substrate. The film forming method according to claim 4

6. The metal film contains one or more elements selected from Ru, W, and Mo. The film forming method according to Claim 5.

7. In the above (B), (Ba') selectively forming an inhibitory film that inhibits the formation of the catalyst layer in the second region with respect to the first region; (Bb') after (Ba'), forming the catalyst layer in the first region; (Bc') After the (Bb'), while decomposing the inhibition film, etching an end portion of the catalyst layer facing the inhibition film using components of the inhibition film; The film formation method according to claim 1, having the above. **Claim 8** (D) After the (B) and before the (C), activating the catalyst layer by supplying a gas made into plasma to the surface of the substrate on which the catalyst layer is formed. The film formation method according to claim 1, having the above. (D) After the (B) and before the (C), activating the catalyst layer by supplying a gas made into plasma to the surface of the substrate on which the catalyst layer is formed. The film formation method according to claim 1, having the above. A processing container; A holding unit that holds the substrate inside the processing container; A gas supply mechanism that supplies gas inside the processing container; A gas discharge mechanism that discharges gas from inside the processing container; A transfer mechanism that transfers the substrate into and out of the processing container; A control unit that controls the gas supply mechanism, the gas discharge mechanism, and the transfer mechanism and implements the film formation method according to any one of claims 1 to 8; A film forming apparatus comprising the above.

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