JP2022099153A - Film formation method, film formation device, and raw materials for self-assembled monolayer - Google Patents

Abstract

To provide a technique for forming a homogeneous self-assembled monolayer on the surface of a metal film.SOLUTION: A film formation method includes the following steps (A) to (D). In the step (A), a substrate having a first region where an insulating film is exposed and a second region where the metal film is exposed is prepared. In the step (B), an organic compound including a head group containing a plurality of thiol groups and a chain portion having the head group at one end in one molecule is supplied to the surface of the substrate. In the step (C), the organic compound is selectively adsorbed on the second region of the first region and the second region to form a self-assembled monolayer. In the step (D), the self-assembled monolayer is used to form a second insulating film in the first region while inhibiting the formation of the second insulating film in the second region.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a film forming method, a film forming apparatus, and a raw material for a self-assembled monolayer.

Patent Document 1 describes a thiol-based compound represented by the general formula R-SH as a raw material for a self-assembled monolayer. R is an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and a part of hydrogen may be replaced with a halogen element. Examples of thiol compounds include CH ₃ (CH ₂ ) ₁₇ SH, CH ₃ (CH ₂ ) ₅ SH, and CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SH.

Japanese Unexamined Patent Publication No. 2020-152976

One aspect of the present disclosure provides a technique for forming a homogeneous self-assembled monolayer on the surface of a metal film.

The film forming method of one aspect of the present disclosure includes the following (A) to (D). (A) A substrate having a first region where the insulating film is exposed and a second region where the metal film is exposed is prepared. (B) An organic compound containing a head group containing a plurality of thiol groups (SH groups) and a chain portion having the head group at one end in one molecule is supplied to the surface of the substrate. (C) The organic compound is selectively adsorbed on the second region of the first region and the second region to form a self-assembled monolayer. (D) Using the self-assembled monolayer, the second insulating film is formed in the first region while inhibiting the formation of the second insulating film in the second region.

According to one aspect of the present disclosure, a homogeneous self-assembled monolayer can be formed on the surface of the metal film.

FIG. 1 is a flowchart showing a film forming method according to an embodiment. FIG. 2A is a diagram showing step S1 of the substrate according to one embodiment, FIG. 2B is a diagram showing step S2 of the substrate according to one embodiment, and FIG. 2C is a diagram showing step S2 of the substrate according to one embodiment. It is a figure which shows the step S3 of. FIG. 3A is a plan view showing a SAM formed on the surface of a metal film according to a conventional example, and FIG. 3B is a diagram schematically showing an enlarged region B of FIG. 3A. be. FIG. 4A is a plan view showing the arrangement of S atoms contained in the head group of the organic compound according to the embodiment, and FIG. 4B is a C which is bonded to the S atom shown in FIG. 4A. It is a top view which shows an example of the arrangement of atoms. FIG. 5A is a perspective view showing an example of a structure in which three S atoms are arranged at the vertices of the smallest equilateral triangle, and FIG. 5B is a perspective view showing three S atoms arranged at the vertices of the largest equilateral triangle. It is a perspective view which shows an example of the structure. 6 (A) is a diagram showing step S1 of the substrate according to the first modification, FIG. 6 (B) is a diagram showing step S2 of the substrate according to the first modification, and FIG. 6 (C) is a first modification. It is a figure which shows the step S3 of the substrate which concerns on. 7 (A) is a diagram showing step S1 of the substrate according to the second modification, FIG. 7 (B) is a diagram showing step S2 of the substrate according to the second modification, and FIG. 7 (C) is a second modification. It is a figure which shows the step S3 of the substrate which concerns on. FIG. 8 is a plan view showing a film forming apparatus according to an embodiment. FIG. 9 is a cross-sectional view showing an example of the first processing unit of FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding configurations may be designated by the same reference numerals and description thereof may be omitted.

First, the film forming method according to the present embodiment will be described with reference to FIGS. 1 and 2. The film forming method includes, for example, steps S1 to S3 shown in FIG. The film forming method may include steps other than steps S1 to S3. Further, the film forming method may include steps S2 to S3 repeatedly a plurality of times.

First, in step S1 of FIG. 1, the substrate 1 is prepared as shown in FIG. 2 (A). Preparing the substrate 1 includes, for example, carrying the carrier C into the film forming apparatus 100 shown in FIG. The carrier C accommodates a plurality of substrates 1.

The substrate 1 has a base substrate 10 such as a silicon wafer or a compound semiconductor wafer. The compound semiconductor wafer is not particularly limited, and is, for example, a GaAs wafer, a SiC wafer, a GaN wafer, or an InP wafer.

The substrate 1 has an insulating film 11 formed on the base substrate 10. A conductive film or the like may be formed between the insulating film 11 and the base substrate 10. 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 Si to O in the SiO film is not limited to 1: 1. The same applies to the SiN film, the SiOC film, the SiON film, and the SiOCN film. The insulating film 11 has a recess on the surface 1a of the substrate 1. The recess is a trench, contact hole or via hole.

The substrate 1 has a metal film 12 that is filled inside the recess. The metal film 12 is not particularly limited, but is, for example, a Cu film, a Co film, a Ru film, or a W film.

The substrate 1 further has a barrier membrane 13 formed along the recesses. The barrier film 13 suppresses metal diffusion from the metal 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 TaN film means a film containing tantalum (Ta) and nitrogen (N). The atomic ratio of Ta to N in the TaN film is not limited to 1: 1. The same applies to the TiN film.

Table 1 summarizes specific examples of the insulating film 11, the metal film 12, and the barrier film 13.

The combination of the insulating film 11, the metal film 12, and the barrier film 13 is not particularly limited.

As shown in FIG. 2A, the substrate 1 has a first region A1 on which the insulating film 11 is exposed and a second region A2 where the metal film 12 is exposed on the surface 1a thereof. Further, the substrate 1 may further have a third region A3 on the surface 1a on which the barrier membrane 13 is exposed. The third region A3 is formed between the first region A1 and the second region A2. The structure of the substrate 1 is not limited to the structure shown in FIG. 2A, as will be described later.

The substrate 1 may be subjected to a step of removing the natural oxide film before being subjected to the step S2 of FIG. The natural oxide film is formed on the surface of the metal film 12. Removal of the natural oxide film includes, for example, supplying hydrogen (H ₂ ) gas to the surface 1a of the substrate 1. Hydrogen gas reduces and removes the natural oxide film. Hydrogen gas may be heated to a high temperature in order to promote a chemical reaction. Further, the hydrogen gas may be plasmatized in order to promote the chemical reaction.

The removal of the natural oxide film is not limited to the dry treatment, and may be a wet treatment. For example, for removing the natural oxide film, a solution such as citric acid (C (OH) (CH ₂ COOH) ₂ COOH) may be supplied to the surface 1a of the substrate 1. After that, the substrate 1 is washed with pure water or the like and dried.

Next, in step S2 of FIG. 1, as shown in FIG. 2 (B), the organic compound which is the raw material of SAM 17 is supplied to the surface 1a of the substrate 1. The above organic compound is supplied in a gaseous state in this embodiment, but may be supplied in a liquid state. The organic compound contains a thiol group, which will be described in detail later.

The thiol group is more easily chemisorbed on the metal film 12 than the insulating film 11. Therefore, the organic compound can be selectively chemically adsorbed to the second region A2 of the first region A1 and the second region A2 to form SAM17. The thiol group is less likely to be chemically adsorbed on the barrier membrane 13 than the metal film 12. Therefore, the SAM 17 does not have to be formed in the third region A3.

Next, in step S3 of FIG. 1, as shown in FIG. 2C, the raw material gas, which is the raw material of the second insulating film 18, is supplied to the surface 1a of the substrate 1, and the second region A2 is used using the SAM 17. The second insulating film 18 is formed in the first region A1 while inhibiting the formation of the second insulating film 18 in the above. The second insulating film 18 is formed on the insulating film 11 and is not formed on the metal film 12. The second insulating film 18 may also be formed on the barrier film 13.

The second insulating film 18 is formed by a CVD (Chemical Vapor Deposition) method or an ALD (Atomic Layer Deposition) method. The second insulating film 18 is not particularly limited, and is, for example, an AlO film, a SiO film, a SiN film, a ZrO film, an HfO film, or the like. Here, the AlO film means a film containing aluminum (Al) and oxygen (O). The atomic ratio of Al to O in the AlO film is not limited to 1: 1. The same applies to the SiO film, SiN film, ZrO film, and HfO film. The second insulating film 18 may be a film made of the same material as the insulating film 11, or may be a film made of a different material.

When the AlO film is formed by the ALD method, an Al-containing gas such as TMA (trimethylaluminum) gas and an oxidizing gas such as water vapor ( _H2O gas) are alternately supplied to the surface 1a of the substrate 1. .. Since water vapor does not adsorb to the hydrophobic SAM 17, AlO selectively deposits in the first region A1. In addition to the Al-containing gas and the oxidizing gas, a reforming gas such as hydrogen gas may be supplied to the substrate 1. These raw material gases may be plasmatized to facilitate the chemical reaction. In addition, these raw material gases may be heated in order to promote a chemical reaction.

When the HfO film is formed by the ALD method, an Hf-containing gas such as tetrakisdimethylamide hafnium (TDHA: Hf [N (CH ₃ ) ₂ ] ₄ ) gas and an oxidizing gas such as water vapor (H ₂ O gas) are used. It is alternately supplied to the surface 1a of the substrate 1. Since water vapor does not adsorb to the hydrophobic SAM17, HfO selectively deposits in the first region A1. In addition to the Hf-containing gas and the oxidizing gas, a reforming gas such as hydrogen gas may be supplied to the substrate 1. These raw material gases may be plasmatized to facilitate the chemical reaction. In addition, these raw material gases may be heated in order to promote a chemical reaction.

Next, with reference to FIG. 3, the organic compound which is the raw material of SAM117 according to the conventional example will be described. The conventional organic compound contains a head group containing one thiol group (SH group) and a chain portion having the head group at one end in one molecule. Patent Document 1 exemplifies CH ₃ (CH ₂ ) ₁₇ SH, CH ₃ (CH ₂ ) ₅ SH, CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SH, and the like.

As shown in FIG. 3B, the S atom of the organic compound is chemically adsorbed on the surface of the metal film 112 to form SAM117. SAM117 contains a chain of organic compounds, the chain of which may be oriented by intramolecular interaction.

When the orientation is strong, a plurality of SAM117s having different orientations may be formed on the surface of the metal film 112. A gap 118 is formed at the boundary of a plurality of SAMs 117 having different orientations. When the raw material gas of the second insulating film 18 is supplied to the gap 118, the second insulating film 18 is deposited.

The problem that the gap 118 is generated is remarkable when the orientation of the chain portion is strong, and is remarkable when the chain portion is an alkyl group. Alkyl group is a general term for the remaining hydrocarbon groups obtained by removing one H atom from an aliphatic saturated hydrocarbon. It is considered that the alkyl group contains a C atom and an H atom, and an intramolecular interaction occurs depending on the polarity of the CH bond, resulting in a strong orientation.

On the other hand, when the chain portion of the organic compound contains an F atom instead of the H atom, the intramolecular interaction between the chain portions is small. Therefore, the orientation is weak, a homogeneous SAM is likely to be formed, and the gap 118 is difficult to be formed. However, it is generally desired not to use organic fluorine compounds.

The raw material of SAM17 according to the present embodiment contains a head group containing a plurality of thiol groups (SH groups) and a chain portion having the head group attached to one end in one molecule. For example, the raw material of SAM17 is represented by the following general formula (1).

In the above general formula (1), R0 is a chain portion, and the remaining R1, R2, R3 and C are head groups. R0 preferably does not contain fluorine (F). Further, it is preferable that R0 does not contain a halogen element other than fluorine. Halogen elements other than fluorine are chlorine (Cl), bromine (Br) or iodine (I). Although R0 preferably does not contain fluorine, it may contain fluorine.

R0 is, for example, an alkyl group having 6 or more and 100 or less C atoms. When the number of C atoms in the chain portion is 6 or more, the length of the chain portion is long, the chain portion can densely cover the surface of the metal film 12, and the deposition of the second insulating film 18 can be suppressed. On the other hand, when the number of C atoms in the chain portion is 100 or less, the head easily comes into contact with the surface of the metal film 12, and the adsorption reaction easily proceeds.

R0 is preferably a linear alkyl group having 6 or more and 100 or less C atoms. The linear alkyl group tends to exhibit a spiral structure or a folded structure. Therefore, the linear alkyl group can densely cover the surface of the metal film 12 and suppress the deposition of the second insulating film 18.

R1, R2 and R3 are organic groups or hydrogen, respectively. At least one of R1, R2 and R3 contains a thiol group. Only one of R1, R2 and R3 may contain a plurality of thiol groups, or R1, R2 and R3 may each contain a thiol group. The head group may contain a plurality of thiol groups.

Next, the arrangement of S atoms contained in the head group of the organic compound according to the embodiment will be described with reference to FIG. 4 (A). FIG. 4A shows the arrangement of S atoms chemically adsorbed on the Cu film. The S atom constitutes a thiol group. It is known that the S atom is generally arranged in the center of three Cu atoms.

The atomic radius of the Cu atom is 128 pm, and one S atom is present in the diamond-shaped region C (area 85134 pm ² ) of FIG. 4 (A). The head group of the conventional organic compound contains one thiol group and one S atom. In this case, the surface density of SAM on the surface of the Cu film is 1 molecule / 85134 pm ² .

On the other hand, the head group of the organic compound of the present embodiment contains n (n is an integer of 2 or more) thiol groups and n S atoms. Therefore, the surface density of SAM on the surface of the Cu film can be reduced by 1 / n times as compared with the conventional example. This effect can be obtained with a metal film other than the Cu film. Candidates other than the Cu film will be described later.

According to this embodiment, the distance between the chain portions can be increased, and the intramolecular interaction between the chain portions can be reduced. As a result, the strength of the orientation of the chain portion can be weakened, and a homogeneous SAM 17 can be formed on the surface of the metal film 12. Therefore, the deposition of the second insulating film 18 on the surface of the metal film 12 can be suppressed.

The head group of the organic compound preferably contains 3 or more thiol groups. As shown in FIG. 4B, when the head group contains three thiol groups, the surface density of SAM on the surface of the Cu film is 1 molecule / 255402 pm ² . Note that C1 to C4 shown in FIG. 4 (B) are the same C atoms as C1 to C4 shown in FIGS. 5 (A) and 5 (B).

According to the findings of the present inventor, when the silane coupling agent, which is a raw material for SAM, is chemically adsorbed on the silicon oxide film, the orientation of the alkyl chain, which is the chain portion of the silane coupling agent, is not recognized. The surface density of SAM on the surface of the silicon oxide film is 1 molecule / 227023 pm ² .

When the head group of the organic compound contains three or more thiol groups, the areal density of SAM on the surface of the Cu film can be lower than the areal density of SAM on the surface of the silicon oxide film. Therefore, the strength of the orientation of the chain portion can be weakened, and a homogeneous SAM 17 can be formed on the surface of the metal film 12.

The head group of the organic compound preferably contains 6 or less thiol groups. When the number of thiol groups contained in the head group is 6 or less, the molecular density of SAM17 on the surface of the Cu film is high, and SAM17 tends to suppress the deposition of the second insulating film 18.

The metal element of the metal film 12 is not limited to Cu. The metal element of the metal film 12 may be one or more selected from, for example, Fe, Co, Ni, Cu, Zn, Ru, Pd, Ag, Pt, and Au. A thiol group can be chemically adsorbed on any of the above metal elements.

Table 2 shows the atomic radius and the covalent radius of the metal element, the covalent radius of the C atom, and the covalent radius of the S atom.

As shown in Table 2, the atomic radii of the above metal elements are 124 pm to 144 pm. For example, the atomic radius of a Cu atom is 128 pm. An adsorption site exists in the center of the three Cu atoms, and the distance between the centers of the adsorption sites is 457 pm.

If a plurality of S atoms can be arranged at a plurality of adsorption sites without distorting the structure of the head group, the S atoms can be stably chemically adsorbed on the metal film 12. Therefore, next, the distance between the S atom and the center of the S atom will be described.

FIG. 5 shows a head group when R1, R2 and R3 are CH ₂ SH, respectively. The four C atoms (C2 to C5) shown in FIG. 5 form ^four sp3 hybrid orbitals with the central C atom (C1) to form a regular tetrahedral structure. C5 is one end of a chain portion of an organic compound. An S atom is connected to C2, C3 and C4.

When the following (1) to (4) are satisfied, there is no distortion in the bond between C1, C2 and S. (1) The angle formed by C1, C2 and C3 is 109.5 °. (2) The angle formed by C1, C2 and S is also 109.5 °. (3) The distance between the centers of C1 and C2 is 154 pm. (4) The distance between the centers of C2 and S is 182 pm.

When S is rotated around a straight line connecting the centers of C1 and C2 while satisfying the above conditions (1) to (4), the distance between the centers of S atoms and S atoms changes. The structure in which the distance is the shortest is shown in FIG. 5 (A), and the structure in which the distance is the longest is shown in FIG. 5 (B). In FIGS. 5 (A) and 5 (B), the three S atoms are arranged at the vertices of an equilateral triangle.

The distance between the S atom and the center of the S atom varies in the range of 251 pm to 449 pm. The upper limit (449 ppm) is close to the distance between the centers of the adsorption sites (457 pm). Therefore, the S atom can be arranged at the adsorption site without distorting the structure of the head group, and the S atom can be stably chemically adsorbed on the metal film 12.

The metal element of the metal film 12 may be other than the metal element shown in Table 2. For example, a thiol group can be adsorbed on any of Rh, Cd, Os, and Ir. Therefore, the metal film 12 is a single metal or a single metal containing one or more metal elements selected from Fe, Co, Ni, Cu, Zn, Ru, Pd, Ag, Pt, Au, Rh, Cd, Os, and Ir. It may be an alloy, preferably a single metal.

The number of C atoms connecting the plurality of thiol groups by the shortest path (the minimum number of C atoms provided between the plurality of thiol groups) may be 2 or more. The larger the number of C atoms, the larger the number of joints, the higher the degree of freedom, and the wider the range in which the distance between the S atom and the center of the S atom can be taken. The shortest distance is shorter and the longest distance is longer.

The wider the range in which the distance between the S atom and the center of the S atom can be taken, the easier it is to place the S atom at the adsorption site. However, if the number of joints is too large, the degree of freedom is too high and control becomes difficult. The number of C atoms connecting a plurality of thiol groups by the shortest path is preferably 3 to 10.

Next, the processing of the substrate 1 according to the first modification will be described with reference to FIG. As shown in FIG. 6A, the substrate 1 of this modification further has a fourth region A4 on the surface 1a on which the liner film 14 is exposed. The fourth region A4 is formed between the second region A2 and the third region A3. The liner film 14 is formed on the barrier film 13 and supports the formation of the metal film 12. The metal film 12 is formed on the liner film 14. The liner film 14 is not particularly limited, but is, for example, a Co film or a Ru film.

Table 3 summarizes specific examples of the insulating film 11, the metal film 12, the barrier film 13, and the liner film 14.

The combination of the insulating film 11, the metal film 12, the barrier film 13, and the liner film 14 is not particularly limited.

The thiol group of the organic compound, which is the raw material of SAM 17, is more likely to be chemically adsorbed to the liner film 14 than to the insulating film 11. Therefore, in step S2 of this modification, as shown in FIG. 6B, the second region A2 and the fourth region A2 of the first region A1, the second region A2, the third region A3, and the fourth region A4 The organic compound can be selectively chemically adsorbed on the region A4 to form SAM17. SAM17 is not formed in the first region A1 and the third region A3.

Further, in step S3 of this modification, as shown in FIG. 6C, SAM17 is used to inhibit the formation of the second insulating film 18 in the second region A2 and the fourth region A4, while the first region A1 and the first region A1 and the fourth region A4 are formed. The second insulating film 18 is formed in the third region A3. The second insulating film 18 is formed on the insulating film 11 and the barrier film 13, and is not formed on the metal film 12 and the liner film 14.

Next, the process of the substrate 1 according to the second modification will be described with reference to FIG. 7. As shown in FIG. 7A, the substrate 1 of this modification has a metal film 12 as a cap film. A second metal film 15 made of a metal different from the metal film 12 is embedded in the recess of the insulating film 11. A metal film 12 is formed on the second metal film 15, and the metal film 12 covers the second metal film 15.

Table 4 summarizes specific examples of the insulating film 11, the metal film (cap film) 12, the barrier film 13, the liner film 14, and the second metal film 15.

The combination of the insulating film 11, the metal film 12, the barrier film 13, the liner film 14, and the second metal film 15 is not particularly limited.

In step S2 of this modification, as shown in FIG. 7B, the second region A2 and the fourth region A4 of the first region A1, the second region A2, the third region A3, and the fourth region A4 are formed. Optionally, the organic compound can be chemically adsorbed and SAM17 can be formed. SAM17 is not formed in the first region A1 and the third region A3.

Further, in step S3 of this modification, as shown in FIG. 7C, SAM17 is used to inhibit the formation of the second insulating film 18 in the second region A2 and the fourth region A4, while the first region A1 and the first region A1 and the fourth region A4 are formed. The second insulating film 18 is formed in the third region A3. The second insulating film 18 is formed on the insulating film 11 and the barrier film 13, and is not formed on the metal film 12 and the liner film 14.

Next, with reference to FIG. 8, the film forming apparatus 100 that implements the above film forming method will be described. As shown in FIG. 8, the film forming apparatus 100 includes a first processing unit 200A, a second processing unit 200B, a transport unit 400, and a control unit 500. The first processing unit 200A carries out step S2 of FIG. The second processing unit 200B carries out step S3 of FIG. The first processing unit 200A and the second processing unit 200B have similar structures. Therefore, it is possible to carry out all of steps S2 to S3 in FIG. 1 only by the first processing unit 200A. The transport unit 400 transports the substrate 1 to the first processing unit 200A and the second processing unit 200B. The control unit 500 controls the first processing unit 200A, the second processing unit 200B, and the transport unit 400.

The transport unit 400 has a first transport chamber 401 and a first transport mechanism 402. The internal atmosphere of the first transport chamber 401 is an atmospheric atmosphere. A 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 the rail 404. The rail 404 extends in the arrangement direction of the carriers C.

Further, the transport unit 400 has a second transport chamber 411 and a second transport mechanism 412. The internal atmosphere of the second transport chamber 411 is a vacuum atmosphere. A second transport mechanism 412 is provided inside the second transport chamber 411. The second transfer mechanism 412 includes an arm 413 that holds the substrate 1, and the arm 413 is arranged so as to be movable in the vertical direction and the horizontal direction and rotatably around the vertical axis. The first processing unit 200A and the second processing unit 200B are connected to the second transfer chamber 411 via different gate valves G.

Further, the transport unit 400 has a load lock chamber 421 between the first transport chamber 401 and the second transport chamber 411. The internal atmosphere of the load lock chamber 421 is switched between a vacuum atmosphere and an atmospheric atmosphere by a pressure regulating mechanism (not shown). As a result, the inside of the second transport chamber 411 can always be maintained in a vacuum atmosphere. Further, it is possible to suppress the inflow of gas from the first transport chamber 401 to the second transport chamber 411. A gate valve G is provided between the first transport chamber 401 and the load lock chamber 421, and between the second transport chamber 411 and the load lock chamber 421.

The control unit 500 is, for example, a computer, and has a CPU (Central Processing Unit) 501 and a storage medium 502 such as a memory. The storage medium 502 stores programs that control various processes executed by the film forming apparatus 100. The control unit 500 controls the operation of the film forming apparatus 100 by causing the CPU 501 to execute the program stored in the storage medium 502. The control unit 500 controls the first processing unit 200A, the second processing unit 200B, and the transport unit 400 to carry out the above film forming method.

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, conveys 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 the atmospheric atmosphere to the vacuum atmosphere. After that, the second transfer mechanism 412 takes out the substrate 1 from the load lock chamber 421 and conveys the taken out substrate 1 to the first processing unit 200A.

Next, the first processing unit 200A carries out step S2. After that, the second transfer mechanism 412 takes out the substrate 1 from the first processing unit 200A and conveys 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 oxidation of the substrate 1 can be suppressed.

Next, the second processing unit 200B carries out step S3. After that, the second transfer mechanism 412 takes out the substrate 1 from the second processing unit 200B, conveys 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 the vacuum atmosphere to the atmospheric atmosphere. After that, 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. Then, the processing of the substrate 1 is completed.

Next, the first processing unit 200A will be described with reference to FIG. Since the second processing unit 200B is configured in the same manner as the first processing unit 200A, illustration and description thereof will be omitted.

The first processing unit 200A includes a substantially cylindrical airtight processing container 210. An exhaust chamber 211 is provided in the center of the bottom wall of the processing container 210. The exhaust chamber 211 has, for example, a substantially cylindrical shape that projects downward. An exhaust pipe 212 is connected to the exhaust chamber 211, for example, on the side surface of the exhaust chamber 211.

An exhaust source 272 is connected to the exhaust pipe 212 via a pressure controller 271. The pressure controller 271 includes a pressure adjusting valve such as a butterfly valve. The exhaust pipe 212 is configured so that the inside of the processing container 210 can be depressurized by the exhaust source 272. The pressure controller 271 and the exhaust source 272 form a gas discharge mechanism 270 that discharges the gas in the processing container 210.

A transport port 215 is provided on the side surface of the processing container 210. The transport port 215 is opened and closed by the gate valve G. The loading / unloading of the substrate 1 between the inside of the processing container 210 and the second transport chamber 411 (see FIG. 8) is performed via the transport port 215.

A stage 220, which is a holding portion for holding the substrate 1, is provided in the processing container 210. The stage 220 holds the substrate 1 horizontally with the surface 1a of the substrate 1 facing up. The stage 220 is formed in a substantially circular shape in a plan view, and is supported by the support member 221. On the surface of the stage 220, for example, a substantially circular recess 222 for mounting a substrate 1 having a diameter of 300 mm is formed. The recess 222 has an inner diameter slightly larger than the diameter of the substrate 1. The depth of the recess 222 is configured to be substantially the same as, for example, the thickness of the substrate 1. The stage 220 is made of a ceramic material such as aluminum nitride (AlN). Further, the stage 220 may be formed of a metal material such as nickel (Ni). Instead of the recess 222, a guide ring for guiding the substrate 1 may be provided on the peripheral edge of the surface of the stage 220.

For example, a grounded lower electrode 223 is embedded in the stage 220. A heating mechanism 224 is embedded below the lower electrode 223. The heating mechanism 224 heats the substrate 1 mounted on the stage 220 to a set temperature by supplying power from a power supply unit (not shown) based on a control signal from the control unit 500 (see FIG. 8). When the entire stage 220 is made of metal, the entire stage 220 functions as a lower electrode, so that the lower electrode 223 does not have to be embedded in the stage 220. The stage 220 is provided with a plurality of (for example, three) elevating pins 231 for holding and elevating the substrate 1 mounted on the stage 220. The material of the elevating pin 231 may be, for example, ceramics such as alumina (Al ₂ O ₃ ), quartz, or the like. The lower end of the elevating pin 231 is attached to the support plate 232. The support plate 232 is connected to an elevating mechanism 234 provided outside the processing container 210 via an elevating shaft 233.

The elevating mechanism 234 is installed, for example, in 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 raised and lowered without interfering with the support member 221 of the stage 220. The elevating pin 231 is vertically configured by the elevating mechanism 234 between above the surface of the stage 220 and below the surface of the stage 220.

The top wall 217 of the processing container 210 is provided with a gas supply unit 240 via an insulating member 218. The gas supply unit 240 forms an upper electrode and faces the lower electrode 223. A high frequency power supply 252 is connected to the gas supply unit 240 via a matching unit 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. Is generated. The plasma generation unit 250 that generates plasma includes a matching unit 251 and a high frequency power supply 252. The plasma generation unit 250 is not limited to capacitively coupled plasma, and may generate other plasma such as inductively coupled plasma. When plasma processing is not required, the first processing unit 200A may not include the plasma generation unit 250.

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

A gas supply mechanism 260 is connected to the gas supply chamber 241 via a gas supply path 261. The gas supply mechanism 260 supplies the gas used in at least one of steps S2 to S3 of FIG. 1 to the gas supply chamber 241 via the gas supply path 261. Although not shown, the gas supply mechanism 260 includes individual pipes, an on-off valve provided in the middle of the individual pipes, and a flow rate controller provided in the middle of the individual pipes for each type of gas, although not shown. When the on-off valve opens the individual pipe, gas is supplied from the supply source to the gas supply path 261. The supply amount is controlled by the flow rate 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 path 261 is stopped.

Although the film forming method, the film forming apparatus, and the embodiment of the raw material of the self-assembled monolayer according to the present disclosure have been described above, the present disclosure is not limited to the above-described embodiment and the like. Various changes, modifications, replacements, additions, deletions, and combinations are possible within the scope of the claims. Of course, they also belong to the technical scope of the present disclosure.

1 Substrate 1a Surface 11 Insulation film 12 Metal film 17 SAM (Self-assembled monolayer)
18 2nd insulating film A1 1st region A2 2nd region

Claims (11)

To prepare a substrate having a first region where the insulating film is exposed and a second region where the metal film is exposed on the surface.
To supply the surface of the substrate with an organic compound containing a head group containing a plurality of thiol groups (SH groups) and a chain portion having the head group at one end in one molecule.
To selectively adsorb the organic compound to the second region of the first region and the second region to form a self-assembled monolayer.
Using the self-assembled monolayer to form the second insulating film in the first region while inhibiting the formation of the second insulating film in the second region.
A film forming method including. The film forming method according to claim 1, wherein the head group of the organic compound has two or more carbon atoms connecting a plurality of the thiol groups by the shortest route. The film forming method according to claim 1 or 2, wherein the chain portion of the organic compound does not contain fluorine. The film forming method according to claim 3, wherein the chain portion of the organic compound is an alkyl group having 6 or more carbon atoms. The film forming method according to claim 4, wherein the chain portion of the organic compound is a linear alkyl group having 6 or more carbon atoms. With the processing container
A holding portion that holds the substrate inside the processing container,
A gas supply mechanism that supplies gas to the inside of the processing container,
A gas discharge mechanism that discharges gas from the inside of the processing container,
A transport mechanism for loading and unloading the substrate to and from the processing container,
A control unit that controls the gas supply mechanism, the gas discharge mechanism, and the transport mechanism to carry out the film forming method according to any one of claims 1 to 5.
A film forming apparatus. A self-assembled monolayer, which is an organic compound containing a head group containing a plurality of thiol groups (SH groups) adsorbed on a metal film and a chain portion having the head group attached to one end in one molecule. material. The raw material for the self-assembled monolayer according to claim 7, wherein the head group of the organic compound has two or more carbon atoms connecting a plurality of the thiol groups by the shortest route. The raw material for the self-assembled monolayer according to claim 7 or 8, wherein the chain portion of the organic compound does not contain fluorine. The raw material for the self-assembled monolayer according to claim 9, wherein the chain portion of the organic compound is an alkyl group having 6 or more carbon atoms. The raw material for the self-assembled monolayer according to claim 10, wherein the chain portion of the organic compound is a linear alkyl group having 6 or more carbon atoms.

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