Film formation post-processing method and substrate processing device

Abstract

[Problem] To suppress the occurrence of metal contamination on, and adhesion of particles to, a zirconium film formed on a substrate. [Solution] Provided is a film formation post-processing method for performing a process on a chamber having a processing space in which is performed a film formation process for supplying a zirconium-chloride-containing processing gas in a state in which a substrate is accommodated and forming a film configured from zirconium on the substrate, at least a part of the chamber exposed to the processing space being configured from an aluminum-containing material, wherein the method has a processing gas discharge step for stopping the supply of the processing gas after the film formation process and discharging the processing gas from the processing space, and a hydrogen-nitride-based gas supply step for supplying a hydrogen-nitride-based gas into the processing space after the processing gas discharge step.

Description

Post-film formation processing method and substrate processing apparatus

[0001] The present disclosure relates to a film formation post-processing method and a substrate processing apparatus.

[0002] For example, in logic ICs as semiconductor devices, titanium (Ti) silicide and nickel (Ni) silicide are used as contact materials for the source and drain. However, with the recent trend toward miniaturization of devices, the contact areas also tend to shrink, resulting in higher resistance at the contact areas. Therefore, in order to reduce the resistance at the contact areas, the use of zirconium (Zr) silicide, a low-resistivity metal, as a contact material has been considered.

[0003] Such zirconium silicide is formed on a wafer, which is a silicon-based semiconductor substrate, by heat treating a zirconium film formed by sputtering, vapor deposition, or ion plating (see, for example, Patent Document 1). The zirconium film is formed on the wafer by, for example, supplying a source gas, which is the raw material for the zirconium film, into an aluminum chamber and generating plasma from the source gas inside the chamber.

[0004] International Publication No. 2007 / 063908

[0005] The technology according to the present disclosure suppresses the occurrence of metal contamination and the adhesion of particles to a zirconium film formed on a substrate.

[0006] One aspect of the technology disclosed herein is a film-forming post-processing method for processing a chamber having a processing space into which a substrate is stored and into which a processing gas containing zirconium chloride is supplied to perform a film-forming process to form a film composed of zirconium on the substrate, and at least a portion of the chamber exposed to the processing space is made of a material containing aluminum, the film-forming post-processing method comprising: a processing gas exhaust step of stopping the supply of the processing gas after the film-forming process and exhausting the processing gas from the processing space; and a hydrogen nitride-based gas supply step of supplying a hydrogen nitride-based gas into the processing space after the processing gas exhaust step.

[0007] According to the present disclosure, it is possible to suppress the occurrence of metal contamination and the adhesion of particles to a zirconium film formed on a substrate.

[0008] 1 is a schematic vertical sectional view showing an example of a substrate processing apparatus according to the present disclosure; FIG. 2 is a block diagram showing an example of a hardware configuration of the substrate processing apparatus shown in FIG. 1; FIG. 3 is a graph showing an example of a comparison of the occurrence of metal contamination in the substrate processing apparatus shown in FIG. 1 and a conventional substrate processing apparatus; FIG. 4 is a graph showing an example of a comparison of the number of particles adhering to a wafer in the substrate processing apparatus shown in FIG. 1 and a conventional substrate processing apparatus; FIG. 5 is a graph showing an example of a relationship between the product of the partial pressure of a hydrogen nitride-based gas and the supply time of the hydrogen nitride-based gas in the substrate processing apparatus shown in FIG. 1, and aluminum atom distribution, which is an index of the occurrence of metal contamination; FIG. 6 is a flowchart showing an example of a process performed in the substrate processing apparatus shown in FIG. 1;

[0009] As described above, in the technique of Patent Document 1, zirconium films are sequentially formed on multiple wafers. However, when zirconium chloride gas is used as the deposition gas, repeated formation of zirconium films on each wafer can result in chlorine remaining inside the chamber. This chlorine reacts with aluminum in the chamber to produce aluminum chloride, which then adheres to the zirconium film on the wafer as metallic foreign matter, resulting in the problem of metal contamination. Furthermore, when zirconium films are repeatedly formed on each wafer, zirconium films and zirconium chloride films can also be formed on the inner walls of the chamber. Another problem is that these films can break down and peel off from the inner walls of the chamber, adhering to the zirconium film on the wafer as particles.

[0010] In contrast, in the technique according to the present disclosure, a hydrogen nitride gas is supplied into the chamber after the zirconium film is formed, thereby suppressing the occurrence of metal contamination and the adhesion of particles to the zirconium film on the wafer.

[0011] Hereinafter, an embodiment of the technology according to the present disclosure will be described with reference to the drawings. However, the configurations described in the following embodiments are merely examples and are not intended to be limiting. For example, each component included in this configuration can be replaced with any component that can perform the same function. Furthermore, any component may be added.

[0012] FIG. 1 is a schematic vertical cross-sectional view showing an example of a substrate processing apparatus according to the present disclosure. The substrate processing apparatus 1 shown in FIG. 1 performs a film formation process for forming a film composed of Zr (zirconium) on a wafer (substrate) W. The substrate processing apparatus 1 includes a Zr film formation chamber 2, a mounting table 3, a shower head 4, a process gas supply unit 5, a high-frequency power supply 6, and an exhaust system 7. The Zr film formation chamber 2 is substantially cylindrical, and its internal space, a processing space U, is depressurized. The processing space U accommodates a wafer W. Then, in the processing space U with the wafer W accommodated therein, a Zr film formation process is performed by plasma CVD. The volume of the processing space U is preferably, for example, 15 L to 30 L, and more preferably 20 L to 25 L. This allows for adequate space for installing the mounting table 3 and the like, and for an arm (not shown) that transfers the wafer W into and out of the processing space U. Furthermore, at least a portion of the Zr film-forming chamber 2 exposed to the processing space U (for example, the cross-hatched portion in FIG. 1 ) is made of a material containing Al (aluminum). Hereinafter, this portion made of a material containing Al will be referred to as the "aluminum-constituting portion 23." Note that it is preferable that the temperature of the aluminum-constituting portion 23 during the film-forming process be 200°C or less, even if heat is input from plasma or the like. This prevents the aluminum-constituting portion 23 from softening during the film-forming process.

[0013] A mounting table 3 is disposed below the processing space U. The mounting table 3 has a mounting surface 31 on which a wafer W is placed. A heater 32 is embedded in the mounting table 3. The heater 32 preferably adjusts the surface temperature of the mounting surface 31 during the film formation process to, for example, 300°C to 500°C, and more preferably 420°C to 480°C. This allows the wafer W to be heated appropriately during the film formation process, thereby ensuring the formation of a Zr film on the wafer W. The mounting table 3 may also be configured to be movable vertically by a drive mechanism (not shown). A shower head 4 made of a metal material such as aluminum is disposed on the ceiling of the Zr film formation chamber 2. In the processing space U between the mounting table 3 and the shower head 4, zirconium chloride (IV) (ZrCl ) is introduced as a processing gas, as will be described later. ４ ) gas to zirconium chloride (ZrCl ｘ ) plasma is generated.

[0014] It is preferable that the surfaces of components, such as the mounting table 3 and the shower head 4, at least partially exposed to the processing space U, are covered with an underlayer made of an oxygen-free material, such as aluminum nitride (AlN). This prevents oxidation of these components and prevents the release of chlorine (Cl), which will be described later. ２ ) and can prevent corrosion due to gases, etc. Furthermore, since the underlayer and the aluminum component 23 do not contain oxygen, even if the underlayer or the aluminum component 23 is etched by plasma, for example, oxygen is not released, and oxidation of the Zr film can be suppressed.

[0015] A sidewall of the Zr film formation chamber 2 is provided with a load / unload port 21 for loading / unloading the wafer W into / from the processing space U, and a gate valve 22 for opening / closing the load / unload port 21. An exhaust system 7 is disposed at the bottom of the Zr film formation chamber 2. The exhaust system 7 includes a pump (not shown), such as a turbomolecular pump or a dry pump, for exhausting the processing space U, and an exhaust valve (not shown), such as an APC (Auto Pressure Controller) valve, for controlling the pressure in the processing space U.

[0016] The shower head 4 is disposed opposite the wafer W placed on the mounting table 3. The shower head 4 has a gas diffusion chamber 41 formed therein and a number of gas holes 42 that connect the gas diffusion chamber 41 to the processing space U. A processing gas supply unit 5 is connected to the shower head 4 via a pipe 51. The processing gas supply unit 5 supplies ZrCl as a processing gas. ４ Gas is supplied to the gas diffusion chamber 41. ZrCl ４ Gas is introduced into the processing space U through the gas holes 42. The processing gas is ZrCl ４ The gas may contain, for example, a diluent gas, such as Ar gas.

[0017] A high frequency power supply 6 is connected to the shower head 4. The high frequency power supply 6 can supply high frequency power for generating plasma of, for example, 450 kHz to the shower head 4. This allows the shower head 4 to function as an upper electrode, generating an electric field in the processing space U. The electric field generated in the processing space U is applied to the ZrCl 2 introduced into the processing space U. ４ The gas is excited and decomposed to form ZrCl ４ A plasma is generated. ４ The plasma adheres to the wafer W, and the adhered ZrCl ４ For the reducing gas, H ２ By supplying gases simultaneously, excited H radicals are generated, which cause a reduction reaction, resulting in ZrCl ４ Chlorine (Cl) is removed from the gas, thereby forming a Zr film on the wafer W. ２ In addition to gases, hydrogen halides such as HCl and SiH ４ etc. may also be used.

[0018] Fig. 2 is a block diagram showing an example of a hardware configuration of the substrate processing apparatus shown in Fig. 1. As shown in Fig. 2, the substrate processing apparatus 1 includes a control unit 10 communicably connected to the processing gas supply unit 5 and the like. The control unit 10 is made up of a computer having at least a CPU 11 and a memory 12. The memory 12 stores in advance various recipes (programs) for executing the film formation process and post-film formation processes, which will be described later.

[0019] As described above, the substrate processing apparatus 1 is an apparatus for forming a Zr film on a wafer W in the Zr film formation chamber 2. The Zr film formation chamber 2 has an aluminum-constituted portion 23 made of aluminum in at least a part thereof exposed to the processing space U. ４ When the gas is used as a processing gas, as the formation of Zr films on wafers W is repeated, Cl ions are generated inside the Zr film forming chamber 2. ２ Gas may remain. ２ The gas reacts with the aluminum component 23 in the Zr film formation chamber 2 to form AlCl ｘ (aluminum chloride) is produced. ｘ This may cause metal contamination, in which the metal particles adhere to the Zr film on the wafer W as metallic foreign matter. Furthermore, when the Zr film is repeatedly formed on the wafer W, the Zr film and ZrCl ｘ As time passes, these films may break into small pieces and peel off from the inner wall of the Zr film-forming chamber 2. These peeled pieces may then adhere to the Zr film on the wafer W as particles.

[0020] Therefore, the substrate processing apparatus 1 is configured to be able to suppress the occurrence of metal contamination and particle adhesion to the Zr film on the wafer W by performing a post-film-forming processing method for processing the Zr film in the Zr film-forming chamber 2 after film formation. The configuration and operation will be described below.

[0021] As shown in FIG. 1, the substrate processing apparatus 1 is ３ Gas supply unit (hydrogen nitride gas supply means) 8, N ２ The substrate processing apparatus 1 includes a gas supply unit 9. When performing the film formation post-processing method, the substrate processing apparatus 1 supplies NH ３ A gas supply step (a hydrogen nitride gas supply step), and N ２ The gas supply step (nitrogen gas supply step) is carried out separately. ３ The gas supply step is NH ３ NH ３ This is a step of supplying (ammonia) gas into the processing space U. ２The gas supply step is N ２ Gas supply unit 9 supplies N ２ This is a step of supplying (nitrogen) gas into the processing space U.

[0022] In addition, in the substrate processing apparatus 1, NH ３ Prior to the gas supply process, a wafer loading process, a film forming process, and a ZrCl ４ The gas exhaust process (process gas exhaust process) and the unloading process are performed in this order. The wafer loading process is a process of loading a wafer W before film formation into the processing space U. The film formation process is a process of loading a ZrCl 2 gas, which is a processing gas, into the processing space U. ４ This is a process in which a gas is supplied into the processing space U to form a Zr film on the wafer W. ４ The gas exhaust process is performed by discharging the treatment gas ZrCl ４ This is a process of discharging gas from the processing space U. The unloading process is a process of unloading the wafer W from the processing space U after film formation.

[0023] In the wafer loading step, first, the gate valve 22 is opened. Next, the wafer W is loaded into the processing space U by the arm that loads and unloads the wafer W, and placed on the mounting table 3. Next, the arm retracts from the processing space U, and the gate valve 22 is closed. This makes it possible to perform film formation in the next film formation step.

[0024] In the film formation process, as described above, ZrCl ４ The gas is supplied into the processing space U, and the ZrCl ４ A plasma is generated from the gas, and a Zr film is formed on the wafer W. As described above, the film formation conditions at this time are preferably such that the surface temperature of the mounting surface 31 is adjusted to, for example, 400°C or higher and 450°C or lower. It is also preferable to reduce the pressure in the processing space U to, for example, several tens of mTorr. Furthermore, it is preferable to supply power to the shower head 4 as high-frequency power for generating plasma, for example, 450 kHz. After the film formation process is continued for a predetermined time, ZrCl ４ When the gas supply is stopped, the supply of high frequency power, i.e., the generation of plasma, is also stopped. ４ Gas exhaust process and N ２ This is also maintained during the gas supply process.

[0025] ZrCl ４ In the gas exhaust process, the exhaust system 7 is operated to remove ZrCl 2 remaining in the processing space U. ４ In this embodiment, the exhaust system 7 not only functions as a pressure adjusting means for adjusting the pressure in the processing space U when plasma is generated, but also exhausts gases such as ZrCl ４ It also functions as a processing gas exhaust means for exhausting gas from the processing space U. ４ In the gas exhaust step, ZrCl ４ By exhausting the gas, it is preferable to make the pressure in the processing space U approximately the same as the pressure outside the gate valve 22. This makes it possible to suppress or prevent, for example, dust and dirt from scattering within the processing space U when the gate valve 22 is opened in the next unloading step.

[0026] In the unloading step, first, the gate valve 22 is opened. Then, the arm unloads the wafer W on the mounting table 3 from the processing space U. Then, the gate valve 22 is closed.

[0027] NH ３ In the gas supply step, NH ３ NH ３ Gas is supplied into the processing space U. ３ The gas supply unit 8 is connected to the Zr film formation chamber 2 via a pipe 80. A switching valve 81 for opening and closing the pipe 80 is disposed midway along the pipe 80. When the switching valve 81 is opened and a switching valve 91 (described later) is closed, NH ３ NH ３ By switching the switching valve 81 to the closed state, NH ３ NH from the gas supply unit 8 to the Zr film formation chamber 2 ３ The gas supply can be stopped.

[0028] N ２ In the gas supply step, N ２ Gas supply unit 9 supplies N２ Gas is supplied into the processing space U. ２ The gas supply unit 9 is connected via a pipe 90 to a portion of the pipe 80 downstream of the switching valve 81. A switching valve 91 for opening and closing the pipe 90 is disposed midway along the pipe 90. By closing the switching valve 81 and opening the switching valve 91, N ２ The gas supply unit 9 supplies N ２ The gas can be supplied. ２ The gas is NH ３ The gas is exhausted from the Zr film forming chamber 2 by the exhaust system 7 together with decomposition products, which will be described later, that are generated in the gas supply process. ２ The NH gas or Ar gas acts as a purge gas. ３ This prevents decomposition products generated in the gas supply process from adhering to the wafer W and the structures of the Zr film formation chamber 2. By switching the switching valve 81 to a closed state, N ２ N from the gas supply unit 9 to the Zr film formation chamber 2 ２ The gas supply can be stopped.

[0029] As described above, when the formation of Zr films on wafers W is repeated, Cl may accumulate inside the Zr film-forming chamber 2, i.e., in the processing space U. ２ Gas may remain. ２ The gas reacts with the aluminum component 23 of the Zr film formation chamber 2 to produce AlCl 3 , which is a cause of metal contamination. ｘ is generated on the surface of the aluminum component 23. ３ The gas supply process ３ The gas is supplied into the processing space U. At this time, at least one of the following chemical reaction formulas (1) and (2) occurs in the processing space U: NH ３ + AlCl ｘ →AlN+NH ｙ Cl ｚ +H ２ ... (1) NH ３ + AlCl ｘ →Al + NHｙ Cl ｚ +H ２ ... (2)

[0030] A specific example of the chemical reaction formula (1) is the following chemical reaction formula (3): ３ + AlCl ３ →AlN+3NH ４ Cl... (3)

[0031] A specific example of chemical reaction formula (2) is the following chemical reaction formula (4): ３ +2AlCl ３ +3H ２ → 2Al + 6NH ４ Cl... (4)

[0032] As shown in these chemical reaction formulas (1) to (4), AlCl ｘ Even if NH is generated, ３ By supplying the gas, the AlCl ｘ is aluminum (Al), aluminum nitride (AlN), ammonium chloride (NH ４ Cl) and hydrogen (H ２ ) gas, i.e., AlCl ｘ is no longer present inside the Zr film formation chamber 2, ｘ This can prevent metal contamination from occurring due to the separation of the aluminum component 23 from the surface and adhering to the Zr film of the wafer W as metallic foreign matter. ２ " corresponds to "H ２ " is missing, but this is not a problem. Similarly, the right side of chemical reaction formula (4) contains the "H ２ " corresponds to "H ２ " is missing, but this is not a particular problem.

[0033] Also, AlCl ｘ and N.H. ３ Since Al and AlN produced by the reaction are chemically stable, they remain on the surface of the aluminum component 23 and do not peel off.４ Cl has a high vapor pressure and evaporates easily, ２ Like the gas, it is exhausted from the inside of the Zr film formation chamber 2 by the exhaust system 7. ｘ and N.H. ３ Since decomposition products generated by the reaction of (a) and (b) do not adhere to the Zr film of the wafer W, it is possible to suppress the occurrence of contamination due to these decomposition products.

[0034] 3 is a graph showing an example of a comparison of the occurrence of metal contamination in the substrate processing apparatus shown in FIG. 1 and a conventional substrate processing apparatus. ｘ As an index of the occurrence of metal contamination due to the above, the "aluminum atom distribution" which is the number of Al atoms (aluminum atoms) adhering to the wafer W per unit area is used. ３ The aluminum atom distribution in the substrate processing apparatus 1 performing the gas supply process is expressed as "NH ３ with post-treatment" and NH ３ The aluminum atom distribution in a conventional substrate processing apparatus that does not perform a gas supply process is shown as "conventional."

[0035] As shown in the graph in Figure 3, ３ In both the "with post-treatment" and "conventional" methods, the distribution density of Al atoms (aluminum atoms) tends to decrease as the number of processed wafers W increases. ３ The aluminum atom distribution is significantly lower in the "with post-treatment" than in the "conventional" case. ３ It can be said that the gas supplying step exerts an effect of suppressing the occurrence of metal contamination of Al.

[0036] Furthermore, inside the Zr film forming chamber 2, Cl that has not completely reacted with the aluminum component 23 remains. ２ It is possible that gas is present, but NH ３ In the gas supply step, Cl ２ The gas is NH ３ Reacts with gas to form NH ４ Cl gas and H ２ These NH４ Cl gas and H ２ The gas is exhausted from the inside of the Zr film formation chamber 2 by the exhaust system 7, so that NH ３ By supplying gas, Cl ２ Gases can also be removed.

[0037] Furthermore, as described above, when the formation of a Zr film on the wafer W is repeated, the Zr film and ZrCl 2, which may become particles, are deposited on the inner wall of the Zr film forming chamber 2. ｘ A film may be formed. ３ The gas supply process ３ The gas is supplied into the processing space U. At this time, at least one reaction of the following chemical reaction formulas (5) and (6) occurs in the processing space U: ３ +2Zr→2ZrN+3H ２ ... (5) NH ３ + ZrCl ｘ →Zr+NH ｙ Cl ｚ +H ２ ...(6)

[0038] Specific examples of chemical reaction formula (5) include the following chemical reaction formulas (7) to (9): ３ +ZrCl→ZrN+NH ４ Cl+H ２ ... (7) 6NH ３ +2ZrCl ２ → 2ZrN + 4NH ４ Cl+H ２ ... (8) 6NH ３ +4ZrCl→4ZrN+2NH ４ Cl ２ +5H ２ ... (9)

[0039] As shown in these chemical reaction formulas (5) to (9), the Zr film and ZrCl ｘ Even if a film is formed, NH ３ By supplying the gas, the AlCl ｘ is zirconium (Zr), zirconium nitride (ZrN), NH ４ Cl gas and H ２It is decomposed into gas. ｘ Since the film does not remain as it is formed, it is possible to prevent the film from being broken into small pieces and peeled off, and adhering to the Zr film of the wafer W as particles.

[0040] Also, Zr, ZrCl ｘ and N.H. ３ Since Zr and ZrN produced by the reaction are chemically stable, they remain on the inner wall of the Zr film-forming chamber 2 and do not peel off. ４ Cl is easily vaporized, and H ２ Like gas, it is exhausted from the inside of the Zr film formation chamber 2 by the exhaust system 7. ｘ and N.H. ３ Decomposition products generated by the reaction of (a) and (b) do not peel off from the inner wall of the Zr film-forming chamber 2 and adhere to the Zr film on the wafer W, which also suppresses the adhesion of particles caused by these decomposition products. In addition, since ZrN is a stable inorganic compound, it can also function as a protective film that protects the aluminum component 23.

[0041] 4 is a graph showing an example of a comparison of the number of particles adhering to a wafer between the substrate processing apparatus shown in FIG. 1 and a conventional substrate processing apparatus. ３ The number of particles per wafer W in the substrate processing apparatus 1 performing the gas supply process is defined as "NH ３ with post-treatment" and NH ３ The number of particles per wafer W in a conventional substrate processing apparatus that does not perform a gas supply process is shown as "conventional".

[0042] As shown in the graph in FIG. ４ The number of particles per wafer W is significantly reduced in the "with post-treatment" compared to the "conventional" method. ４ The number of particles per wafer W in the "with post-processing" mode is suppressed to 5 or less. ３ It can be said that the gas supplying step exerts an effect of suppressing particle adhesion.

[0043] NH ３ In the gas supply step, NH ３ Gas partial pressure and NH ３ It is preferable to adjust the supply time of the gas. Fig. 5 is a graph showing an example of the relationship between the product of the partial pressure of the hydrogen nitride gas and the supply time of the hydrogen nitride gas in the substrate processing apparatus shown in Fig. 1 and the aluminum atom distribution, which is an index of the occurrence of metal contamination. As shown in the graph of Fig. 5, ３ Gas partial pressure and NH ３ As the product of the gas supply time and the time of supply increases, the aluminum atom distribution decreases. ３ Gas partial pressure and NH ３ When the product of the gas supply time is 25 Torr·sec or more, the decrease in the aluminum atom distribution saturates. Therefore, from the viewpoint of suppressing the occurrence of metal contamination of Al, ３ Gas partial pressure and NH ３ It is preferable that the product of the gas supply time is 25 Torr·sec or more. This makes it possible to suppress the occurrence of metal contamination of Al. ３ From the viewpoint of reducing gas consumption and improving throughput, NH ３ Gas partial pressure and NH ３ It is preferable that the product of the gas supply time is small. Therefore, it is preferable that the product is set to 25 Torr·sec or more and 40 Torr·sec or less. ３ This makes it possible to reduce the amount of gas used, improve throughput, and suppress the occurrence of metal contamination of Al.

[0044] In addition, when obtaining the relationship shown in FIG. ３ In the gas supply step, NH ３ The gas flow rate is set to 800 sccm or more and 10,000 sccm or less, and NH ３ The gas supply time was set to 10 seconds or more and 60 seconds or less, and the pressure in the processing space U was set to 1 Torr or more and 9 Torr or less. ３ From the viewpoint of reducing gas consumption, NH ３It is preferable to set the gas flow rate to 800 sccm or more and 4000 sccm or less. ３ It is preferable that the gas supply time is set to 10 seconds or more and 40 seconds or less. ４ From the viewpoint of promoting the vaporization of Cl, it is preferable that the pressure in the processing space U be set to 1 Torr or more and 9 Torr or less.

[0045] Also, NH ３ In the gas supply step, the temperature of the aluminum component 23 in the Zr film formation chamber 2 may be set to be equal to or higher than the temperature of the aluminum component 23 during the film formation process. This allows, for example, for dust or dirt to be thermally shrunk and peeled off from the aluminum component 23, and the NH ４ Cl gas and H ２ It can be quickly removed together with the gas from the inside of the Zr film formation chamber 2. In this case, too, the temperature is preferably 200° C. or less to prevent the aluminum component 23 from softening.

[0046] NH ３ In this embodiment, the gas supply step is performed with plasma generation stopped, but this is not limiting and the gas supply step may be performed with plasma generated. The plasma density is high at and around the shower head 4, and NH ３ NH produced from gas ３ The plasma promotes the reactions of the above-mentioned chemical reaction formulas (5) to (9), and therefore the Zr film and ZrCl ｘ The film can be removed in a concentrated manner.

[0047] In addition, NH ３ In this embodiment, the gas supplied in the gas supply step is NH ３ However, the present invention is not limited to this gas, and any hydrogen nitride gas may be used. ３ Examples of other nitrogen-containing gases include N ２ H ４ (hydrazine) gas, etc.

[0048] Next, modified examples of the order of steps performed in the substrate processing apparatus 1 will be described with reference to Figures 6A to 6D. Figures 6A to 6D are flowcharts showing an example of steps performed in the substrate processing apparatus shown in Figure 1. In the modified example shown in Figure 6A, the order of steps includes a wafer loading step, a film forming step, a ZrCl ４ Gas discharge process, carrying out process, NH ３ Gas supply step, N ２ The gas supply steps are carried out in order, but NH ３ Gas supply process and N ２ The gas supply process is repeated. ２ Instead of the gas, Ar gas may be used. ３ Gas partial pressure and NH ３ Since it is preferable that the product of gas supply time is 25 Torr·sec or more, NH ３ When repeating the gas supply process, NH ３ The partial pressure of the gas and NH ３ The cumulative total gas supply time is preferably 25 Torr·sec or more.

[0049] In the modification shown in FIG. 6B, the wafer loading step, the film forming step, and the ZrCl ４ Gas discharge process, carrying out process, NH ３ The gas supply steps are carried out in sequence, but N ２ The gas supply step (Ar gas supply step) is omitted. ２ By omitting the gas supply step, the throughput can be further improved.

[0050] The modified example shown in FIG. 6C corresponds to a case where a plurality of film forming steps are repeated. In this case, NH ３ Gas supply process and N ２ The gas supply process is not performed. That is, the wafer loading process, the film formation process, and the ZrCl ４ The gas exhaust process and the unloading process are repeated, but only after a Zr film is formed on a predetermined number of wafers W, NH ３ Gas supply process and N ２ The gas supply process is repeated to thereby increase the total NH ３ Gas supply process and N ２The number of times the gas supply step is performed can be reduced, and the throughput can be further improved.

[0051] The modification shown in FIG. 6D has a NH ３ Gas supply process and N ２ The gas supply step is not repeated, and N ２ This corresponds to the case where the gas supply process is omitted. ３ Gas supply process and N ２ The number of times the gas supply step is performed can be reduced, and the throughput can be significantly improved.

[0052] Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the gist of the present disclosure.

[0053] This application claims priority based on Japanese Patent Application No. 2024-006671, filed on January 19, 2024, the entire contents of which are incorporated herein by reference.

[0054] 1 Substrate processing apparatus 2 Zr film formation chamber 7 Exhaust system 8 NH ３ Gas supply section 23 Aluminum component U Processing space W Wafer

Claims

1. A post-deposition treatment method for treating a chamber in which a treatment space is provided, in which a film-forming treatment for forming a film composed of zirconium on a substrate is performed by supplying a treatment gas containing zirconium chloride in a state where the substrate is housed, and at least a part of the treatment space exposed to the outside is made of a material containing aluminum, the method comprising: a treatment gas discharge step of stopping the supply of the treatment gas after the film-forming treatment and discharging the treatment gas from the treatment space; and a hydrogen nitride-based gas supply step of supplying a hydrogen nitride-based gas into the treatment space after the treatment gas discharge step.

2. The post-deposition treatment method according to claim 1, wherein in the hydrogen nitride-based gas supply step, the partial pressure of the hydrogen nitride-based gas and the supply time for supplying the hydrogen nitride-based gas are adjusted.

3. The post-deposition treatment method according to claim 2, wherein the product of the partial pressure of the hydrogen nitride-based gas and the supply time for supplying the hydrogen nitride-based gas is 25 Torr·sec or more.

4. The post-deposition treatment method according to claim 1, wherein in the hydrogen nitride-based gas supply step, the flow rate of the hydrogen nitride-based gas is 800 sccm or more and 10,000 sccm or less.

5. The post-deposition treatment method according to claim 1, wherein in the hydrogen nitride-based gas supply step, a film composed of zirconium is formed on a portion of the chamber made of the material containing aluminum to cover the portion.

6. The post-deposition treatment method according to claim 1, wherein a mounting table having a mounting surface on which the substrate is mounted is provided in the treatment space, and the surface temperature of the mounting surface during the film-forming treatment is 400° C. or more and 450° C. or less.

7. The post-deposition treatment method according to claim 1, wherein the temperature of a portion of the chamber made of the material containing aluminum during the film-forming treatment is 200° C. or less.

8. The post-deposition treatment method according to claim 1, wherein the hydrogen nitride-based gas is ammonia gas or hydrazine gas.

9. The post-deposition treatment method according to claim 1, further comprising a nitrogen gas supply step of supplying nitrogen gas into the treatment space after the hydrogen nitride-based gas supply step.

10. The post-deposition treatment method according to claim 9, wherein the hydrogen nitride-based gas supply step and the nitrogen gas supply step are repeated.

11. In the hydrogen-based gas supply step, the partial pressure of the hydrogen-based gas and the supply time for supplying the hydrogen-based gas are adjusted. When repeating the hydrogen-based gas supply step, the cumulative value of the partial pressure of the hydrogen-based gas and the total supply time during which the hydrogen-based gas has been supplied is 25 Torr·sec or more. The post-film formation treatment method according to claim 10.

12. The post-film formation treatment method according to claim 1, further comprising a carry-out step of carrying out the substrate from the treatment space after the treatment gas discharge step.

13. The film formation treatment is a treatment performed by generating plasma from the treatment gas in the treatment space. In the treatment gas discharge step and the hydrogen-based gas supply step, the generation of the plasma is stopped. The post-film formation treatment method according to claim 1.

14. The chamber has a volume of the treatment space of 15 L or more and 30 L or less. The post-film formation treatment method according to claim 1.

15. A substrate processing apparatus comprising a treatment space in which a film formation treatment for forming a film made of zirconium on the substrate is performed by supplying a treatment gas containing zirconium chloride with the substrate accommodated, and at least a part of the treatment space exposed is composed of a material containing aluminum. The apparatus includes treatment gas discharge means for stopping the supply of the treatment gas after the film formation treatment and discharging the treatment gas from the treatment space, and hydrogen-based gas supply means for supplying a hydrogen-based gas into the treatment space after the treatment gas has been discharged from the treatment space by the treatment gas discharge means.

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