Film formation post-processing method and substrate processing device

Abstract

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 for performing 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, where 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.SELECTED DRAWING: Figure 6

Description

Technical Field

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

Background Art

[0002] For example, in a logic IC as a semiconductor device, titanium (Ti) silicide or nickel (Ni) silicide is used as a contact material for a source or a drain. However, with the miniaturization of devices in recent years, as the contact portion is reduced, the resistance of the contact portion tends to increase. Therefore, in order to reduce the resistance of the contact portion, the use of zirconium (Zr) silicide, which is a low-resistance metal, as a contact material has been studied.

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

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[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.

Means for Solving the Problems

[0006] One aspect of the technology according to the present disclosure has a processing space in which a film forming process is performed to form a film made of zirconium on a substrate by supplying a processing gas containing zirconium chloride with the substrate housed, and at least a part of the processing space exposed to the outside is a chamber made of a material containing aluminum. A post-film formation processing method for processing the chamber, comprising: a processing gas discharge step of 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 of supplying a hydrogen nitride-based gas into the processing space after the processing gas discharge step.

Advantages of the Invention

[0007] According to the present disclosure, the occurrence of metal contamination and the adhesion of particles to the zirconium film formed on the substrate can be suppressed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] As described above, in the technology of Patent Document 1, zirconium films are sequentially formed on a plurality of wafers. However, when zirconium chloride gas is used as a film-forming gas, chlorine may remain inside the chamber when the formation of the zirconium film on each wafer is repeated. This chlorine reacts with the aluminum in the chamber to generate aluminum chloride, and there is a problem that this aluminum chloride adheres to the zirconium film of the wafer as a metal foreign substance, causing metal contamination. Further, when the formation of the zirconium film on each wafer is repeated, a zirconium film or a zirconium chloride film may also be formed on the inner wall of the chamber. If these films are finely crushed and peeled off from the inner wall of the chamber, there is also a problem that they adhere to the zirconium film of the wafer as particles.

[0010] On the other hand, in the technology according to the present disclosure, after the formation of the zirconium film, a hydrogen nitride-based gas is supplied into the chamber to suppress the occurrence of metal contamination and the adhesion of particles to the zirconium film of 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 limited by this configuration. For example, each part included in this configuration can be replaced with any one that can exhibit the same function. Also, 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 is an apparatus that performs a film forming process for forming a film made of Zr (zirconium) on a wafer (substrate) W. The substrate processing apparatus 1 includes a Zr film forming chamber (chamber) 2, a mounting table 3, a shower head 4, a processing gas supply unit 5, a high-frequency power source 6, and an exhaust system 7. The Zr film forming chamber 2 has a substantially cylindrical shape, and the processing space U, which is its internal space, is depressurized. Further, the wafer W is stored in the processing space U. Then, in the processing space U in a state where the wafer W is stored, a Zr film forming process by plasma CVD is performed. Note that the volume of the processing space U is preferably, for example, 15 L or more and 30 L or less, and more preferably 20 L or more and 25 L or less. Thereby, for example, an installation space such as the mounting table 3 and an access space for an arm (not shown) for loading and unloading the wafer W into and out of the processing space U can be ensured without excess or deficiency. Further, at least a part of the Zr film forming chamber 2 that is exposed to the processing space U (for example, the portion hatched in FIG. 1) is made of a material containing Al (aluminum). Hereinafter, the portion made of the material containing Al will be referred to as the "aluminum component 23". Note that the temperature of the aluminum component 23 during the film forming process preferably does not exceed 200 degrees even when there is heat input from plasma or the like. Thereby, it is possible to prevent the aluminum component 23 from softening during the film forming process.

[0013] Below the processing space U, a mounting table 3 is arranged. The mounting table 3 has a mounting surface 31 on which the wafer W is mounted. A heater 32 is embedded in the mounting table 3. It is preferable to adjust the surface temperature of the mounting surface 31 during the film formation process to, for example, 300 degrees or more and 500 degrees or less by this heater 32, and more preferably to adjust it to 420 degrees or more and 480 degrees or less. Thereby, for example, during the film formation process, the wafer W can be heated without excess or deficiency, and thus a Zr film can be surely formed on the wafer W. Further, the mounting table 3 may be configured to be movable in the vertical direction by a drive mechanism (not shown). On the ceiling portion of the Zr film formation chamber 2, a shower head 4 made of a metal material such as aluminum, for example, is arranged. In the processing space U between the mounting table 3 and the shower head 4, as will be described later, plasma is generated from zirconium(IV) chloride (ZrCl4) gas as a processing gas to zirconium chloride (ZrCl x )

[0014] Note that the surfaces of components at least partially exposed in the processing space U such as the mounting table 3 and the shower head 4 are preferably covered with an underlayer made of a material containing no oxygen such as aluminum nitride (AlN). Thereby, oxidation of these components can be prevented, and corrosion by chlorine (Cl2) gas or the like described later can be prevented. Further, since the underlayer and the aluminum component 23 do not contain oxygen, for example, even if the underlayer and the aluminum component 23 are etched by plasma, oxygen is not released, and oxidation of the Zr film can be suppressed.

[0015] Further, on the side wall of the Zr film formation chamber 2, a carry-in / outlet 21 for carrying the wafer W into and out of the processing space U and a gate valve 22 for opening and closing the carry-in / outlet 21 are provided. At the bottom of the Zr film formation chamber 2, an exhaust system 7 is arranged. The exhaust system 7 has a pump (not shown) such as a turbo molecular pump or a dry pump for exhausting the inside of the processing space U and an exhaust valve (not shown) such as an APC (Auto Pressure Controller) valve for controlling the pressure inside the processing space U.

[0016] The shower head 4 is arranged to face the wafer W placed on the mounting table 3. The shower head 4 has a gas diffusion chamber 41 formed inside and a number of gas holes 42 that communicate the gas diffusion chamber 41 with the processing space U. Further, the processing gas supply unit 5 is connected to the shower head 4 via a pipe 51. The processing gas supply unit 5 supplies ZrCl4 gas as the processing gas to the gas diffusion chamber 41. The ZrCl4 gas supplied to the gas diffusion chamber 41 is introduced into the processing space U through each gas hole 42. Note that the processing gas only needs to contain ZrCl4 gas, and for example, it may contain a dilution gas. Examples of the dilution gas include Ar gas and the like.

[0017] A high-frequency power supply 6 is connected to the shower head 4. The high-frequency power supply 6 can supply, for example, high-frequency power for plasma generation at 450 kHz to the shower head 4. Thereby, the shower head 4 functions as an upper electrode, and an electric field is generated in the processing space U. The electric field generated in the processing space U excites and decomposes the ZrCl4 gas introduced into the processing space U to generate ZrCl4 plasma. This ZrCl4 plasma adheres to the wafer W, and by simultaneously supplying H2 gas as a reducing gas to the adhered ZrCl4, the excited H radicals cause a reduction reaction, and chlorine (Cl) is removed from ZrCl4, whereby a Zr film is formed on the wafer W. Note that, in addition to H2 gas, hydrogen halides such as HCl and SiH4 may be used as the reducing gas.

[0018] FIG. 2 is a block diagram showing an example of the 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 composed of a computer having at least a CPU 11 and a memory 12, and various recipes (programs) for performing a film formation process and a film formation post-treatment described later are recorded in advance in the memory 12.

[0019] As described above, the substrate processing apparatus 1 is an apparatus for forming a Zr film on a wafer W in a Zr film forming chamber 2. Further, the Zr film forming chamber 2 has an aluminum component 23 made of aluminum at at least a part thereof exposed to the processing space U. When ZrCl4 gas is used as a processing gas in the film forming process in the substrate processing apparatus 1, if the formation of the Zr film on the wafer W is repeated, Cl2 gas may remain inside the Zr film forming chamber 2. This Cl2 gas reacts with the aluminum component 23 of the Zr film forming chamber 2 to generate AlCl x (aluminum chloride). And there is a risk of generating metal contamination in which AlCl x adheres to the Zr film of the wafer W as a metal foreign substance. Also, when repeatedly forming the Zr film on the wafer W, a Zr film or ZrCl x (zirconium chloride) film may be formed on the inner wall of the Zr film forming chamber 2. These films may be finely crushed and peeled off from the inner wall of the Zr film forming chamber 2 over time. And this peeled-off material may adhere to the Zr film of 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 the adhesion of particles to the Zr film on the wafer W by a post-film formation processing method for performing processing on the Zr film forming chamber 2 after film formation. Hereinafter, this configuration and operation will be described.

[0021] As shown in FIG. 1, the substrate processing apparatus 1 includes an NH3 gas supply unit (hydrogen nitride-based gas supply means) 8 and an N2 gas supply unit 9. In this substrate processing apparatus 1, when executing the post-film formation processing method, an NH3 gas supply step (hydrogen nitride-based gas supply step) and an N2 gas supply step (nitrogen gas supply step) are performed individually. The NH3 gas supply step is a step of supplying NH3 (ammonia) gas into the processing space U by the NH3 gas supply unit 8. The N2 gas supply step is a step of supplying N2 (nitrogen) gas into the processing space U by the N2 gas supply unit 9.

[0022] In the substrate processing apparatus 1, prior to the NH3 gas supply step, a wafer loading step, a film formation step, a ZrCl4 gas discharge step (processing gas discharge step), and an unloading step are performed in this order. The wafer loading step is a step of loading the wafer W before film formation into the processing space U. The film formation step is a step of supplying ZrCl4 gas, which is a processing gas, into the processing space U to form a Zr film on the wafer W. The ZrCl4 gas discharge step is a step of discharging ZrCl4 gas, which is a processing gas, from the processing space U. The unloading step is a step of unloading the wafer W after film formation from the processing space U.

[0023] In the wafer loading step, first, the gate valve 22 is opened. Next, the wafer W is carried into the processing space U by the arm for loading and unloading the wafer W and placed on the mounting table 3. Then, the arm retracts from the processing space U, and the gate valve 22 is closed. Thereby, the film formation in the film formation step of the next process becomes possible.

[0024] In the film formation step, as described above, ZrCl4 gas is supplied into the processing space U, plasma is generated from the ZrCl4 gas, and a Zr film is formed on the wafer W. Also, as described above, as the film formation conditions at this time, it is preferable to adjust the surface temperature of the mounting surface 31 to, for example, 400 degrees or more and 450 degrees or less. Further, it is preferable to reduce the pressure in the processing space U to, for example, several tens of mTorr. Furthermore, it is preferable to use, as the supply power to the shower head 4, high-frequency power for plasma generation at, for example, 450 kHz. After continuing the film formation process for a predetermined time, the supply of ZrCl4 gas is stopped, and the supply of high-frequency power, that is, the generation of plasma is also stopped. This stopped state is also maintained in the ZrCl4 gas discharge step and the N2 gas supply step.

[0025] In the ZrCl4 gas discharge step, by operating the exhaust system 7, the gas such as ZrCl4 gas remaining in the processing space U is discharged from the processing space U. Thus, in this embodiment, the exhaust system 7 functions not only as a pressure adjustment means for adjusting the pressure of the processing space U during plasma generation, but also as a processing gas discharge means for discharging the ZrCl4 gas from the processing space U. Then, in the ZrCl4 gas discharge step, it is preferable that the pressure of the processing space U is made approximately the same as the pressure outside the gate valve 22 by discharging the ZrCl4 gas. Thereby, when the gate valve 22 is opened in the subsequent carry-out step, an air flow is generated between the processing space U and the outside of the gate valve 22, and for example, it is possible to suppress or prevent dust and the like from scattering in the processing space U.

[0026] In the carry-out step, first, the gate valve 22 is opened. Next, the wafer W on the mounting table 3 is carried out from the processing space U by the arm. Next, the gate valve 22 is closed.

[0027] In the NH3 gas supply step, NH3 gas is supplied into the processing space U by the NH3 gas supply unit 8. The NH3 gas supply unit 8 is connected to the Zr film formation chamber 2 via a pipe 80. Also, a switching valve 81 for opening and closing the pipe 80 is disposed in the middle of the pipe 80. Then, by opening the switching valve 81 and closing the switching valve 91 described later, NH3 gas can be supplied from the NH3 gas supply unit 8 to the Zr film formation chamber 2 (processing space U) via the pipe 80. By switching the switching valve 81 to the closed state, the supply of NH3 gas from the NH3 gas supply unit 8 to the Zr film formation chamber 2 can be stopped.

[0028] In the N2 gas supply process, N2 gas is supplied into the processing space U by the N2 gas supply unit 9. The N2 gas supply unit 9 is connected via a pipe 90 to a portion downstream of the switching valve 81 of the pipe 80. A switching valve 91 for opening and closing the pipe 90 is disposed in the middle of the pipe 90. Then, by setting the aforementioned switching valve 81 to the closed state and the switching valve 91 to the open state, N2 gas can be supplied from the N2 gas supply unit 9 to the Zr film deposition chamber 2 through the pipe 90 and the pipe 80 in sequence. The supplied N2 gas entrains decomposition products described later generated in the NH3 gas supply process, and together with these, is discharged from the inside of the Zr film deposition chamber 2 by the exhaust system 7. Thus, in the present embodiment, N2 gas or Ar gas functions as a purge gas to prevent the decomposition products generated in the NH3 gas supply process from adhering to the wafer W and the structures of the Zr film deposition chamber 2. Note that by switching to the closed state of the switching valve 81, the supply of N2 gas from the N2 gas supply unit 9 to the Zr film deposition chamber 2 can be stopped.

[0029] Incidentally, as described above, when the formation of the Zr film on the wafer W is repeated, Cl2 gas may remain inside the Zr film deposition chamber 2, that is, in the processing space U. The remaining Cl2 gas reacts with the aluminum component 23 of the Zr film deposition chamber 2 to generate AlCl x on the surface of the aluminum component 23, for example, which causes metal contamination. In contrast, in the NH3 gas supply process, NH3 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. NH3 + AlCl x → AlN + NH y Cl z + H2 ··· (1) NH3 + AlCl x → Al + NH y Cl z + H2 ··· (2)

[0030] As a specific example of the chemical reaction formula (1), the following chemical reaction formula (3) can be cited. 4NH3 + AlCl3 → AlN + 3NH4Cl ··· (3)

[0031] As a specific example of the chemical reaction formula (2), the following chemical reaction formula (4) can be cited. 6NH3 + 2AlCl3 + 3H2 → 2Al + 6NH4Cl ··· (4)

[0032] As shown in these chemical reaction formulas (1) to (4), even if AlCl x is generated on the surface of the aluminum component 23, due to the supply of NH3 gas, the AlCl x is decomposed into aluminum (Al), aluminum nitride (AlN), ammonium chloride (NH4Cl), and hydrogen (H2) gas. That is, since AlCl x no longer exists inside the Zr film formation chamber 2, it is possible to suppress the peeling of AlCl x from the surface of the aluminum component 23 and its adhesion to the Zr film of the wafer W as a metallic foreign substance, thereby suppressing the occurrence of metal contamination. Although the "H2" corresponding to "H2" on the right side of the chemical reaction formula (1) is missing on the right side of the chemical reaction formula (3), there is no particular problem with this. Similarly, although the "H2" corresponding to "H2" on the right side of the chemical reaction formula (2) is missing on the right side of the chemical reaction formula (4), there is also no particular problem with this.

[0033] Also, since Al and AlN generated by the reaction of AlCl x and NH3 are chemically stable, they remain on the surface of the aluminum component 23 and do not peel off. Furthermore, NH4Cl generated by the above reaction has a high vapor pressure and easily vaporizes, and like the H2 gas, it is discharged from the inside of the Zr film formation chamber 2 by the exhaust system 7. Therefore, since the decomposition products generated by the reaction of AlCl x and NH3 do not adhere to the Zr film of the wafer W either, it is also possible to suppress the occurrence of contamination by these decomposition products.

[0034] Figure 3 is a graph showing an example of a comparison of the occurrence status of metal contamination in the substrate processing apparatus shown in Figure 1 and a conventional substrate processing apparatus. In this graph, AlCl xAs an index of the occurrence status of metal contamination caused by [reason], the "aluminum atom distribution", which is the number of Al atoms (aluminum atoms) attached per unit area of the wafer W, is used. Further, the aluminum atom distribution in the substrate processing apparatus 1 that performs the NH3 gas supply process is shown as "with NH3 post-treatment", and the aluminum atom distribution in a conventional substrate processing apparatus that does not perform the NH3 gas supply process is shown as "conventional".

[0035] As shown in the graph of FIG. 3, in both "with NH3 post-treatment" and "conventional", as the number of processed wafers W increases, the distribution density of Al atoms (aluminum atoms) tends to decrease. However, the aluminum atom distribution is significantly lower in "with NH3 post-treatment" than in "conventional". Thus, it can be said that in the substrate processing apparatus 1, the effect of suppressing the occurrence of Al metal contamination is exhibited by the NH3 gas supply process.

[0036] Also, although it is conceivable that unreacted Cl2 gas with the aluminum component 23 exists inside the Zr film formation chamber 2, in the NH3 gas supply process, the Cl2 gas reacts with the NH3 gas and is converted into NH4Cl gas and H2 gas. Since these NH4Cl gas and H2 gas are discharged from the inside of the Zr film formation chamber 2 by the exhaust system 7, the Cl2 gas can also be removed by supplying the NH3 gas.

[0037] Also, as described above, when the formation of the Zr film on the wafer W is repeated, a Zr film or ZrCl that can become particles may be formed on the inner wall of the Zr film formation chamber 2. x In contrast, by the NH3 gas supply process, NH3 gas is supplied into the processing space U. At this time, at least one of the following chemical reaction formulas (5) and (6) occurs in the processing space U. 2NH3 + 2Zr → 2ZrN + 3H2 ···(5) NH3 + ZrCl x → Zr + NH y Cl z + H2 ···(6)

[0038] Specific examples of the chemical reaction formula (5) include the following chemical reaction formulas (7) to (9). 2NH3 + ZrCl → ZrN + NH4Cl + H2 ··· (7) 6NH3 + 2ZrCl2 → 2ZrN + 4NH4Cl + H2 ··· (8) 6NH3 + 4ZrCl → 4ZrN + 2NH4Cl2 + 5H2 ··· (9)

[0039] As shown in these chemical reaction formulas (5) to (9), even if a Zr film or a ZrCl x film is formed on the inner wall of the Zr film formation chamber 2, due to the supply of NH3 gas, the AlCl x is decomposed into zirconium (Zr), zirconium nitride (ZrN), NH4Cl gas, and H2 gas. That is, since the Zr film or the ZrCl x film does not remain, it can be prevented from being finely crushed and peeled off and adhering to the Zr film of the wafer W as particles.

[0040] In addition, since Zr and ZrN generated by the reaction of Zr, ZrCl x and NH3 are chemically stable, they remain on the inner wall of the Zr film formation chamber 2 and do not peel off. Also, as described above, NH4Cl generated by the above reaction easily vaporizes and is discharged from the inside of the Zr film formation chamber 2 by the exhaust system 7, like the H2 gas. Therefore, since the decomposition products generated by the reaction of Zr, ZrCl x and NH3 do not peel off from the inner wall of the Zr film formation chamber 2 and adhere to the Zr film of the wafer W, the adhesion of particles caused by these decomposition products can also be suppressed. Note that since ZrN is a stable inorganic compound, it can also function as a protective film for protecting the aluminum component 23.

[0041] FIG. 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. In this graph, the number of particles per wafer W in the substrate processing apparatus 1 that performs the NH3 gas supply process is shown as "with NH3 post-treatment", and the number of particles per wafer W in a conventional substrate processing apparatus that does not perform the NH3 gas supply process is shown as "conventional".

[0042] As shown in the graph of FIG. 4, the number of particles per wafer W is significantly reduced in "with NH4 post-treatment" compared to "conventional". Specifically, the number of particles per wafer W in "with NH4 post-treatment" is suppressed to 5 or less. Thus, it can be said that in the substrate processing apparatus 1, the effect of suppressing particle adhesion is exhibited by the NH3 gas supply process.

[0043] In the NH3 gas supply process, it is preferable to adjust the partial pressure of the NH3 gas and the supply time of the NH3 gas. FIG. 5 is a graph showing an example of the relationship between the product of the partial pressure of the hydrogen nitride-based gas and the supply time of the hydrogen nitride-based gas in the substrate processing apparatus shown in FIG. 1 and the aluminum atom distribution which is an index of the occurrence state of metal contamination. As shown in the graph of FIG. 5, the aluminum atom distribution decreases as the product of the partial pressure of the NH3 gas and the supply time of the NH3 gas increases. However, when the product of the partial pressure of the NH3 gas and the supply time of the NH3 gas becomes 25 Torr·sec or more, the decrease in the aluminum atom distribution saturates. Therefore, from the viewpoint of suppressing the occurrence of Al metal contamination, it is preferable to set the product of the partial pressure of the NH3 gas and the supply time of the NH3 gas to 25 Torr·sec or more. Thereby, it becomes possible to suppress the occurrence of Al metal contamination. Note that from the viewpoints of reducing the usage amount of the NH3 gas and improving the throughput, it is preferable that the product of the partial pressure of the NH3 gas and the supply time of the NH3 gas is small. Therefore, it is preferable to set the product to 25 Torr·sec or more and 40 Torr·sec or less. Thereby, it is possible to achieve both reduction of the usage amount of the NH3 gas and improvement of the throughput and suppression of the occurrence of Al metal contamination.

[0044] Also, when obtaining the relationship shown in FIG. 5, in the NH3 gas supply step, the flow rate of NH3 gas was set to 800 sccm or more and 10,000 sccm or less, the supply time of NH3 gas was set to 10 sec or more and 60 sec or less, and the pressure in the processing space U was set to 1 Torr or more and 9 Torr or less. However, from the viewpoint of reducing the usage amount of NH3 gas, it is preferable that the flow rate of NH3 gas is 800 sccm or more and 4000 sccm or less. Also, from the viewpoint of improving throughput, it is preferable that the supply time of NH3 gas is 10 sec or more and 40 sec or less. Further, from the viewpoint of promoting the vaporization of NH4Cl, it is preferable that the pressure in the processing space U is 1 Torr or more and 9 Torr or less.

[0045] Also, in the NH3 gas supply step, the temperature of the aluminum component 23 of the Zr film forming chamber 2 may be set to be equal to or higher than the temperature of the aluminum component 23 during the film forming process. Thereby, when dust or dirt adheres to the aluminum component 23, for example, these can be thermally shrunk, peeled off from the aluminum component 23, and quickly removed from the inside of the Zr film forming chamber 2 together with NH4Cl gas and H2 gas. In this case as well, it is preferable that the temperature of the aluminum component 23 is 200 degrees or less in order to prevent softening.

[0046] In the NH3 gas supply step, in this embodiment, it is performed with the plasma generation stopped, but it is not limited thereto, and it may be performed with the plasma generated. The density of the plasma is high at the shower head 4 and its periphery, and since the NH3 plasma generated from the NH3 gas promotes the reactions of the above-described chemical reaction formulas (5) to (9), the Zr film and ZrCl x adhering to the shower head 4 and its periphery can be concentrated and removed.

[0047] Note that the gas supplied in the NH3 gas supply step is NH3 gas in this embodiment, but it is not limited thereto, and any hydrogen nitride-based gas may be used. Examples of other hydrogen nitride-based gases other than NH3 gas include N2H4 (hydrazine) gas and the like.

[0048] Next, a modified example of the order of steps executed in the substrate processing apparatus 1 will be described with reference to FIG. 6. FIG. 6 is a flowchart showing an example of steps executed in the substrate processing apparatus shown in FIG. 1. In the modified example shown in FIG. 6(a), the wafer loading step, the film forming step, the ZrCl4 gas discharging step, the unloading step, the NH3 gas supply step, and the N2 gas supply step are executed in order, and the NH3 gas supply step and the N2 gas supply step are repeated. Note that instead of N2 gas, Ar gas may be used. Here, as described above, since it is preferable that the product of the partial pressure of NH3 gas and the supply time of NH3 gas is 25 Torr·sec or more, when repeating the NH3 gas supply step, it is also preferable that the cumulative value of the partial pressure of NH3 gas and the total supply time during which NH3 gas has been supplied is 25 Torr·sec or more.

[0049] In the modified example shown in FIG. 6(b), the wafer loading step, the film forming step, the ZrCl4 gas discharging step, the unloading step, and the NH3 gas supply step are executed in order, but the N2 gas supply step (Ar gas supply step) is omitted. By omitting the N2 gas supply step, the throughput can be further improved.

[0050] The modified example shown in FIG. 6(c) corresponds to the case where a plurality of film forming steps are repeated. In this case, the NH3 gas supply step and the N2 gas supply step are not executed each time the unloading step is executed. That is, the wafer loading step, the film forming step, the ZrCl4 gas discharging step, and the unloading step are repeated, but after forming a Zr film on a predetermined number of wafers W, the NH3 gas supply step and the N2 gas supply step are repeatedly executed for the first time. Thereby, the number of executions of the NH3 gas supply step and the N2 gas supply step as a whole can be reduced, and the throughput can be further improved.

[0051] The modified example shown in FIG. 6(d) corresponds to the case where the execution of the NH3 gas supply step and the N2 gas supply step is not repeated and the N2 gas supply step is further omitted as compared with the modified example shown in FIG. 6(c). Thereby, the number of executions of the NH3 gas supply step and the N2 gas supply step as a whole can be further reduced, and the throughput can be significantly improved.

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

Description of Reference Numerals

[0053] 1 Substrate processing apparatus 2 Zr film deposition chamber 7 Exhaust system 8 NH3 gas supply unit 23 Aluminum component U Processing space W Wafer

Claims

1. There is a processing space where a film forming process is performed in which a processing gas containing zirconium chloride is supplied with the substrate housed, and a film made of zirconium is formed on the substrate. A post-film formation processing method for processing a chamber in which at least a part exposed to the processing space is made of a material containing aluminum, a processing gas discharge step of stopping the supply of the processing gas after the film forming process and discharging the processing gas from the processing space; a hydrogen nitride-based gas supply step of supplying a hydrogen nitride-based gas into the processing space after the processing gas discharge step. A post-film formation processing method having

2. 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. The post-film formation processing method according to Claim 1.

3. 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. The post-film formation processing method according to Claim 2.

4. In the hydrogen nitride-based gas supply step, the flow rate of the hydrogen nitride-based gas is set to 800 sccm or more and 10,000 sccm or less. The post-film formation processing method according to Claim 1.

5. In the hydrogen nitride-based gas supply step, a film made of zirconium that covers the portion of the chamber made of the material containing aluminum is formed on the portion. The post-film formation processing method according to Claim 1.

6. A mounting table having a mounting surface on which the substrate is mounted is provided in the processing space, The surface temperature of the mounting surface during the film forming process is 400 degrees or more and 450 degrees or less. The post-film formation processing method according to Claim 1.

7. The temperature of the portion of the chamber made of the material containing aluminum during the film forming process is 200 degrees or less. The post-film formation processing method according to Claim 1.

8. The hydrogen nitride-based gas is ammonia gas or hydrazine gas. The post-film formation processing method according to Claim 1.

9. A nitrogen gas supply step of supplying nitrogen gas into the processing space after the hydrogen nitride-based gas supply step. The post-film formation processing method according to Claim 1.

10. The hydrogen nitride-based gas supply step and the nitrogen gas supply step are repeated. The post-film formation processing method according to Claim 9.

11. 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, 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 an unloading step of unloading 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, generation of the plasma is stopped. The post-film formation treatment method according to claim 1.

14. The chamber has a treatment space with 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 composed 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. 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. A substrate processing apparatus comprising hydrogen-based gas supply means for supplying a hydrogen-based gas into the treatment space after discharging the treatment gas from the treatment space by the treatment gas discharge means.

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