JP2013122068A - Method for forming tungsten compound film and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a tungsten compound film which can shorten an incubation time on formation of a tungsten compound film, and to provide a semiconductor device having the tungsten compound film formed by the method.SOLUTION: The method for forming a tungsten compound film includes: a silane gas feeding step in which an SiHgas is fed to a substrate S; a source gas feeding step in which a WFgas is fed to the substrate S; and a reaction gas feeding step in which a reaction gas reacted with tungsten is fed to the substrate S. In the silane gas feeding step, the particles of a silane gas which are larger than the particles of the reaction gas arriving at the surface of the substrate S are made to arrive at the surface of the substrate S, and the respective source gas feeding step and reaction gas feeding step are repeated at a mutually different timing after the silane gas feeding step to form a tungsten compound film on the substrate S.

Description

  The technology of the present disclosure relates to a method of forming a tungsten compound film using an ALD method (Atomic Layer Deposition) and a semiconductor device having the tungsten compound film formed by the method.

  Conventionally, for example, as described in Patent Document 1, a tungsten nitride (WN) film, which is one of tungsten compound films, has been widely used for a barrier metal layer of a copper plug embedded in a via hole or a contact hole. . Of these WN film formation methods, the ALD method, in which several WN films are formed, can provide a WN film having a better step coverage than CVD or sputtering methods. Is attracting particular attention as a manufacturing technique of a semiconductor device that requires the above.

In the ALD method described above, first, supply and exhaust of tungsten hexafluoride (WF ₆ ) gas are sequentially performed on the substrate, and then supply and exhaust of monosilane (SiH ₄ ) gas are sequentially performed. Subsequently, the supply and exhaust of WF ₆ gas are sequentially performed, and then the supply and exhaust of ammonia (NH ₃ ) gas are sequentially performed. As a result, a WN film of several atomic layers is formed on the substrate, and a WN film having a desired film thickness is formed by repeating a film formation cycle in which the above four steps are performed as one cycle.

International Publication No. 2004/061154

  By the way, in recent years, many attempts have been made to increase the degree of integration of elements while reducing the mounting area of the element substrate by three-dimensionally mounting an element substrate, which is a silicon substrate on which elements are formed. . In such three-dimensional mounting, elements formed on different silicon substrates are connected by an electrode (Through Silicon Via: TSV) penetrating the silicon substrate. The WN film is also being used as a barrier metal layer of such TSV.

  On the other hand, among the TSV formation methods, the Via Last method in which TSV is formed after element formation includes the formation of the WN film in a state where the element substrate is bonded to a support substrate that supports the element substrate. Various processes are performed. And since an element substrate and a support substrate are adhere | attached with the adhesive agent whose heat-resistant temperature is 200 degrees C or less, 200 degrees C or less, More preferably 150 degrees C or less is calculated | required also for the formation temperature of a WN film | membrane.

  In this regard, when the above-described ALD method is performed in a state where the substrate temperature is maintained at 200 ° C. or lower, the WN film formation is not started on the substrate unless the film formation cycle is repeated a plurality of times. Recognized by the people. Incidentally, in the incubation time that is the time when the formation of the WN film is not started in this way, WN grown in an island shape is formed sparsely on the surface of the insulating film. Therefore, as a result of the initial film of the WN film growing as described above, the film density of the initial film of the WN film is lowered, and thereby the barrier property of the WN film is lowered.

  Such a problem is not limited to the case where the WN film is used as a barrier metal of TSV, but is generally common even when it is used as a barrier metal of wiring formed in an insulating film. The problem is not limited to the WN film, but is generally common to the formation of other tungsten compound films, such as a tungsten silicide (WSi) film and a tungsten nitride silicide (WSiN) film.

  The technology of the present disclosure has been made in view of the above circumstances, a tungsten compound film forming method capable of shortening an incubation time when forming a tungsten compound film, and a tungsten compound film formed by the method. It is an object to provide a semiconductor device having the following.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
One aspect of the technology of the present disclosure is a method of forming a tungsten compound film, in which a silane gas supply step in which a silane gas is supplied to the substrate, a source gas supply step in which a source gas containing tungsten is supplied to the substrate, A reaction gas supply step in which a reaction gas that reacts with tungsten is supplied to the substrate. In the silane gas supply step, the reaction gas supply step has more particles than the reaction gas particles that reach the surface of the substrate in one reaction gas supply step. The silane gas particles reach the surface of the substrate, and after the silane gas supply step, each of the source gas supply step and the reaction gas supply step is repeatedly performed at different timings, so that As a result, a tungsten compound film is formed.

  The inventors of the present application have found the following while intensively studying a method of forming a tungsten compound film. That is, when more silane gas particles than the reaction gas particles supplied in one reaction gas supply process are supplied to the substrate before the tungsten compound film is formed, the silane gas supply process is not performed. It was found that the incubation time was shortened compared to.

  In this regard, in one aspect of the technology of the present disclosure, the silane gas is supplied to the substrate before the tungsten compound film is formed on the substrate by supplying the source gas and the reaction gas, and the substrate is supplied to the substrate. There are more silane gas particles than reactive gas particles supplied to the substrate in one reactive gas supply step. As a result, the surface of the substrate after the silane gas supply step is more likely to contain a gas that can react with the source gas than the surface of the substrate after the reaction gas supply step. Therefore, as compared with the case where the silane gas supply process is not performed, the probability that the source gas is adsorbed to the entire substrate is increased, and as a result, the incubation time described above can be shortened. Therefore, when the silane gas supply step is not performed, it is possible to form the tungsten compound film without causing the incubation time even at the substrate temperature that causes the incubation time.

  According to another aspect of the method for forming a tungsten compound film in the present disclosure, in the aspect described above, a hydrogen plasma supply step in which plasma generated from hydrogen gas is supplied to the substrate is provided before the silane gas supply step.

  Inventors of the present application are eagerly studying a method of forming a tungsten compound film. Before the silane gas supply step, plasma generated from hydrogen gas is supplied to the surface of the substrate to further increase the incubation time. Was found to be shorter.

  In this regard, in another aspect of the method for forming a tungsten compound film according to the present disclosure, plasma generated from hydrogen gas is supplied to the substrate prior to supply of the silane gas. Thereby, the incubation time can be further shortened compared to the case where only the silane gas is supplied before the source gas and the reaction gas are supplied. As a result, a tungsten compound film can be formed at a lower substrate temperature without causing an incubation time.

  In another aspect of the method for forming a tungsten compound film in the present disclosure, in the above-described aspect, the inert gas plasma in which the plasma generated from the inert gas is supplied to the substrate before the hydrogen plasma supply step is completed. A supply process is provided.

  In the said aspect, an unevenness | corrugation is formed in the surface of a board | substrate by supplying the plasma produced | generated from the inert gas on a board | substrate. Such unevenness increases the probability that the particles supplied on the substrate will be adsorbed, so that the silane gas is more likely to be applied to the substrate than when only the plasma generated from the hydrogen gas is supplied prior to the supply of the silane gas. It becomes easy to adsorb. This shortens the incubation time.

  In another aspect of the method for forming a tungsten compound film in the present disclosure, in the above-described aspect, the supply of the silane gas in the silane gas supply step and the source gas in the source gas supply step performed following the silane gas supply step are the same. Is started simultaneously.

  In the above aspect, since the supply of the silane gas is stopped and the supply of the raw material gas is simultaneously performed, when the raw material gas is supplied, there is a high possibility that more silane is adsorbed on the substrate than after that. . Therefore, the tungsten compound film is easily formed on substantially the entire substrate from the start of the formation of the tungsten compound film.

  According to another aspect of the method for forming a tungsten compound film in the present disclosure, in the aspect described above, the source gas supply step includes a first source gas supply step and a second source gas supply step, and the reaction gas supply step. Comprises a reducing gas supply step in which a silane gas for reducing tungsten is supplied and a nitriding gas supply step in which a nitriding gas for nitriding tungsten is supplied to the substrate. The first source gas supply step, the reaction gas supply The tungsten nitride film, which is the tungsten compound film, is formed on the substrate by repeatedly performing the process, the reducing gas supply process, and the second source gas supply process in order at different timings.

  In the above aspect, when a tungsten nitride film, which is a tungsten compound film, is formed, a nitride having higher reactivity with tungsten than the nitriding gas is supplied to tungsten reduced by the silane gas. Therefore, tungsten is easily nitrided even at a low temperature as described above.

  Another aspect of the method for forming a tungsten compound film in the present disclosure is a method for forming a tungsten compound film, in which a silane gas supply step in which silane gas is supplied to the substrate and a source gas containing tungsten is supplied to the substrate. A source gas supply step; and a reaction gas supply step in which a reaction gas other than the silane gas that reacts with the tungsten is supplied to the substrate, and the source gas supply step and the reaction gas supply after the silane gas supply step. A tungsten compound film is formed on the substrate by repeatedly performing each of the steps with different timings.

  The inventors of the present application increase the probability that the source gas is adsorbed to the substrate by supplying the silane gas before the source gas of the tungsten compound film is supplied to the substrate. It was found that it is easy to form.

  In this regard, in the above aspect, the silane gas is supplied to the substrate before the tungsten compound film is formed by supplying the source gas and the reaction gas other than the silane gas. Thereby, compared with the case where supply of silane gas is not performed, the probability that source gas will adsorb | suck with respect to a board | substrate will become high, and by extension, the incubation time mentioned above will become short.

  One embodiment of the semiconductor device in the present disclosure is a semiconductor device having a tungsten compound film, in which the tungsten compound film is formed in the above-described manner.

  In the above aspect, since the incubation time is shortened when the tungsten compound film is formed, the tungsten compound film formation region in the semiconductor device is formed on the substantially entire region from the start of the formation of the tungsten compound film. A compound film is easily formed. Therefore, the semiconductor device has a tungsten compound film with improved film characteristics such as film density and barrier property.

The block diagram which shows the whole structure of a multi-chamber type film-forming apparatus. Schematic which shows schematic structure of the film-forming chamber which a multi-chamber type | mold film-forming apparatus has. 4 is a timing chart showing how various gases and high-frequency power are supplied in a pretreatment process included in the method for forming a tungsten compound film in the first embodiment of the present disclosure. The timing chart which shows the supply aspect of various gases at the time of forming a WN film as a tungsten compound film. The timing chart which shows the supply aspect of various gas at the time of forming a WSi film as a tungsten compound film. The timing chart which shows the supply aspect of various gas at the time of forming a WSiN film as a tungsten compound film. The timing chart which shows the supply aspect of various gas and the high frequency electric power in the pre-processing process included in the formation method of the tungsten compound film in 2nd Embodiment of this indication. The graph which shows the relationship between the number of film-forming cycles and the thickness of a WN film | membrane. The SEM image which shows the WN film | membrane formed in the hole of a silicon substrate.

[First Embodiment]
Hereinafter, a first embodiment that embodies a method of forming a tungsten compound film according to the present disclosure and a first embodiment that embodies a semiconductor device having the tungsten compound film will be described with reference to FIGS. To do. First, a multi-chamber type film forming apparatus used for forming the tungsten compound film will be described with reference to FIG. In FIG. 1, the direction in which the substrate to be processed is transported is indicated by an arrow.

[Configuration of multi-chamber deposition system]
As shown in FIG. 1, the transfer chamber 11 included in the multi-chamber film forming apparatus 10 includes a carry-in chamber 12, a carry-out chamber 13, a pretreatment chamber 14, a film formation chamber 15, and a seed layer forming chamber 16. It is connected. The transfer chamber 11 is equipped with a transfer robot 11a for transferring a substrate. The substrate is a target of processing in the multi-chamber type film forming apparatus 10, and the element substrate and the support substrate are bonded by an adhesive having a heat resistant temperature of 200 ° C. or less. The element substrate has a silicon substrate in which elements and through holes are formed, and an insulating layer formed on the element substrate, and the insulating layer of the element substrate and the support substrate are bonded to each other. An insulating film such as a silicon oxide film is formed on the upper surface of the silicon substrate constituting the element substrate and in the through hole. In the multi-chamber type film forming apparatus 10, various processes are performed on the surface of the silicon substrate and the inner wall surface of the through hole. The carry-in chamber 12 and the carry-out chamber 13 may be a single load lock chamber having both the carry-in / out functions.

  The transport robot 11a transports the unprocessed substrate carried into the carry-in chamber 12 to the pre-treatment chamber 14, the film formation chamber 15, and the seed layer formation chamber 16 in this order, and processes in these chambers 14-16. Then, the processed substrate is transferred to the carry-out chamber 13.

  The carry-in chamber 12 carries in a substrate before processing from the outside in a state where the inside is at atmospheric pressure, and puts the substrate before processing into the transfer chamber 11 in a state where the inside is reduced from atmospheric pressure by an exhaust unit (not shown). Take it out.

  The carry-out chamber 13 carries in the processed substrate from the transfer chamber 11 in a state where the inside is decompressed by an exhaust unit (not shown), and carries out the processed substrate outside in a state where the inside is at atmospheric pressure.

The pretreatment chamber 14 is a plasma treatment chamber that generates plasma from hydrogen (H ₂ ) gas. Pretreatment chamber 14, for example, a high-frequency power frequency is 13.56MHz to supply the _{H 2} gas to generate a plasma from the _{H 2} gas.

  The film forming chamber 15 is an ALD chamber for forming a tungsten compound film on a substrate by a monoatomic film. The film forming chamber 15 forms, for example, any one of a tungsten nitride film (WN film), a tungsten silicide film (WSi film), and a tungsten nitride silicide film (WSiN film) as the tungsten compound film.

  The seed layer forming chamber 16 is a sputtering chamber for forming a copper (Cu) film on the substrate. The Cu film formed on the substrate serves as a seed layer when copper wiring is formed in the through hole by electrolytic plating.

  The transfer chamber 11, the pretreatment chamber 14, the film formation chamber 15, and the seed layer formation chamber 16 have an exhaust unit (not shown), similar to the carry-in chamber 12 and the carry-out chamber 13, and atmospheric pressure is generated by the exhaust unit. The pressure is maintained under reduced pressure.

[Structure of deposition chamber]
The configuration of the film forming chamber 15 will be described in more detail with reference to FIG. As shown in FIG. 2, a substrate stage 22 that holds the substrate S is installed in a vacuum chamber 21 of the film forming chamber 15. A heater 23 for heating the substrate stage 22 is mounted inside the substrate stage 22. A heater power supply 24 that outputs a direct current is connected to the heater 23. The heater 23 generates heat by supplying current from the heater power supply 24, thereby heating the substrate S to a predetermined temperature via the substrate stage 22.

  Two exhaust ports P1 penetrating the bottom wall 21a are formed in the bottom wall 21a of the vacuum chamber 21. An exhaust unit 25 that exhausts the inside of the vacuum chamber 21 is connected to the two exhaust ports P1. The exhaust unit 25 includes, for example, various vacuum pumps and a valve that adjusts the exhaust flow rate of the vacuum pump.

  A shower plate 26 is attached to the upper wall 21 b of the vacuum chamber 21 at a position facing the substrate stage 22. The shower plate 26 is formed with a plurality of openings 26 a that open to the substrate stage 22 side. A gas supply port P <b> 2 that penetrates the upper wall 21 b of the vacuum chamber 21 and the attachment surface of the shower plate 26 to the upper wall 21 b is formed.

  Connected to the gas supply port P2 are a hydrogen-based gas pipe GL1 for supplying a gas containing hydrogen to the vacuum chamber 21 and a fluorine-based gas pipe GL2 for supplying a gas containing fluorine to the vacuum chamber 21.

The hydrogen-based gas pipe GL1 includes a silane gas pipe connected to a silane gas supply unit 31 that supplies a silane gas such as monosilane (SiH ₄ ) gas to the vacuum chamber 21, and a nitriding gas such as ammonia (NH ₃ ) gas in the vacuum chamber 21. It branches off to a nitriding gas pipe to which the nitriding gas supply section 32 to be supplied is connected. The silane gas pipe is connected to an inert gas supply unit 33 for supplying an inert gas such as nitrogen (N ₂ ) gas to the vacuum chamber 21 through the pipe, while the nitriding gas pipe is connected to the silane gas pipe through the pipe. An inert gas supply unit 34 for supplying N ₂ gas to the vacuum chamber 21 is connected.

The fluorine-based gas pipe GL2 is connected to a source gas supply unit 35 that supplies a source gas containing tungsten such as tungsten hexafluoride (WF ₆ ) gas to the vacuum chamber 21. From the fluorine-based gas pipe GL2, an inert gas pipe to which an inert gas supply unit 36 for supplying N ₂ gas to the vacuum chamber 21 is connected is branched.

[Tungsten compound film formation by multi-chamber type film forming system]
An operation when forming a tungsten compound film, which is one of the operations of the multi-chamber type film forming apparatus 10, will be described with reference to FIGS.
When a tungsten compound film is formed by the multi-chamber type film forming apparatus 10, first, the substrate S before processing is carried into the carry-in chamber 12 by an external transfer robot. When the substrate S is loaded into the loading chamber 12, the substrate S is loaded into the pretreatment chamber 14 by the transfer robot 11a.

Next, in the pretreatment chamber 14, as shown in FIG. 3, at timing T1, supply of H ₂ gas and supply of high-frequency power to the H ₂ gas are started. Accordingly, plasma generated from the H ₂ gas is supplied to the substrate S, and excited species including hydrogen are adsorbed on the surface of the substrate S. When such a hydrogen plasma supply process is continued for a predetermined time, for example, 60 seconds, the supply of H ₂ gas and high-frequency power is stopped at timing T2.
When the H ₂ plasma is supplied, the substrate S is transferred from the pretreatment chamber 14 to the film forming chamber 15 by the transfer robot 11a.

When the substrate S is carried into the film forming chamber 15, supply of SiH ₄ gas from the silane gas supply unit 31 to the vacuum chamber 21 is started at timing T3. At this time, the number of silane gas particles reaching the surface of the substrate S is supplied into the vacuum chamber 21 so that the number of particles of the reaction gas reaching the surface of the substrate S in each subsequent reaction gas supply step is larger. Each of the flow rate, pressure, and supply time of the silane gas is set. For example, the number of silane gas particles reaching the surface of the substrate S increases as the flow rate of the silane gas increases, as the partial pressure of the silane gas increases, and as the supply time of the silane gas increases.

Note that the gas supply mode performed in the film forming chamber 15 is larger in flow rate, pressure, and supply time than the SiH ₄ gas supply mode here, for convenience of forming several atomic layers of tungsten compound films. Limited. For example, in order to prevent the step coverage and barrier properties from being deteriorated due to excessive gas supply, the time during which the source gas or reaction gas is supplied is the time immediately after the source gas or reaction gas reaches the surface of the substrate S. It is short enough to reach the working gas. The flow rate and pressure of the raw material gas and the reactive gas are required to be stable to such an extent that the number of particles reaching the substrate S can be reproduced in a short supply time as described above. Therefore, as a supply mode of the newly added SiH ₄ gas, the pressure at the time of supply is substantially equal to the other steps following the supply, and the number of SiH ₄ gas particles reaching the surface of the substrate S is as follows. Is preferably secured by the flow rate or supply time of the SiH ₄ gas.

Then, SiH ₄ gas is supplied into the vacuum chamber 21 at a flow rate of, for example, 70 sccm. When the supply of SiH ₄ gas is continued for a predetermined time, for example, 60 seconds, the supply of SiH ₄ gas is performed at timing T4. Is stopped. Thereby, SiH ₄ is adsorbed to almost the entire surface of the substrate S through the excited species containing hydrogen.

Similarly, at timing T4, supply of a gas for forming the tungsten compound film is started. As described above, in the present embodiment, any one of a WN film, a WSi film, and a WSiN film is formed as a tungsten compound. Even when any of these tungsten compound films is formed, supply of WF ₆ gas is started at the timing T4. Thus, since the timing at which the supply of SiH ₄ gas is stopped and the timing at which the supply of WF ₆ gas is started are the same, when the WF ₆ gas is supplied, the timing is higher than the subsequent timing. There is a high possibility that SiH ₄ is adsorbed on the substrate S. Therefore, the tungsten compound film is easily formed on substantially the entire substrate S from the start of the formation of the tungsten compound film. In addition, before introducing WF ₆ at timing T4, an evacuation time or an N ₂ gas introduction time for introducing N ₂ gas into the vacuum chamber may be provided for uniformity in the film formation surface and particle countermeasures. In that case, for example, the exhaust time or N ₂ gas introduction time is 1 to 2 seconds.
Hereinafter, supply modes of various gases when forming each of the WN film, the WSi film, and the WSiN film as the tungsten compound film will be described in order.

[Formation of WN film]
When forming the WN film, as shown in FIG. 4, supply of WF ₆ gas as a source gas from the source gas supply unit 35 to the vacuum chamber 21 is started at a timing T11. The WF ₆ gas is supplied into the vacuum chamber 21 at a flow rate of 20 sccm, for example. Then, for example, at the timing T12 after 2 seconds, the supply of the WF ₆ gas is stopped. In such a first source gas supply process, WF ₆ supplied to the substrate S is adsorbed on the substrate S through the SiH ₄ .

When the WF ₆ gas is supplied to the substrate S, the supply of N ₂ gas from the inert gas supply unit 36 to the vacuum chamber 21 is started at the timing T12, and the timing T13 after 2 seconds, for example. Then, the supply of N ₂ gas is stopped. Through such an inert gas supply step, WF ₆ in the vacuum chamber 21 is exhausted together with the N ₂ gas.

When the N ₂ gas is exhausted, supply of SiH ₄ gas as a reducing gas from the silane gas supply unit 31 to the vacuum chamber 21 is started at timing T13. For example, at timing T14 4 seconds later, SiH ₄ Gas supply is stopped. SiH ₄ gas is supplied into the vacuum chamber 21 at a flow rate of, for example, 70 sccm. Through such a reducing gas supply process, WF ₆ and SiH ₄ react on the substrate S, and as a result, a W film of several atomic layers containing Si is formed on the substrate S.

When the W film is formed, supply of N ₂ gas from the inert gas supply unit 33 to the vacuum chamber 21 is started at timing T14. For example, supply of N ₂ gas is performed at timing T15 after 2 seconds. Is stopped. By such an inert gas supply process, the SiH ₄ gas in the vacuum chamber 21 is exhausted together with the N ₂ gas.

When the exhaust gas by the N ₂ gas is carried out, at the timing T15, supplied from the raw material gas supply unit 35 of the WF ₆ gas into the vacuum chamber 21 is started again, for example, at two seconds after the timing T16, the WF ₆ gas Supply is stopped. The WF ₆ gas is supplied into the vacuum chamber 21 at a flow rate of 10 sccm, for example. By such a second source gas supply step, WF ₆ is adsorbed on the substrate S on which the W film is formed.

When the WF ₆ gas is supplied, N ₂ gas is supplied from the inert gas supply unit 36 to the vacuum chamber 21 from timing T16 to timing T17. Through such an inert gas supply step, WF ₆ in the vacuum chamber 21 is exhausted together with the N ₂ gas.

When the N ₂ gas is exhausted, the supply of NH ₃ gas as the nitriding gas from the nitriding gas supply unit 32 to the vacuum chamber 21 is started at timing T17. For example, at timing T18 two seconds later, the NH ₃ gas is supplied. ₃ Gas supply is stopped. NH ₃ gas is supplied into the vacuum chamber 21 at a flow rate of 5 sccm, for example. By such a nitriding gas supply step, W (NH ₂ ) F ₅ having a higher reactivity with W than NH ₃ is generated by a reaction between WF ₆ adsorbed on the substrate S and NH ₃ . When this W (NH ₂ ) F ₅ reacts with W formed on the substrate S, a WN film of several atomic layers is formed.

When the WN film is formed, supply of N ₂ gas from the inert gas supply unit 34 to the vacuum chamber 21 is started at timing T18. For example, supply of N ₂ gas is performed at timing T19 after 2 seconds. Is stopped. Through such an inert gas supply process, NH ₃ in the vacuum chamber 21 is exhausted together with N ₂ gas.

Such a period from timing T11 to timing T19 is one cycle, and the film formation cycle is repeated a predetermined number of times, whereby a WN film having a predetermined film thickness is formed. Note that the timing T11 in the first cycle corresponds to the timing T4. Further, in the formation of the WN film, the SiH ₄ gas as the reducing gas and the NH ₃ gas as the nitriding gas constitute a reactive gas.

[Formation of WSi film]
When forming the WSi film, as shown in FIG. 5, various gases are supplied in the same manner as from the timing T11 to the timing T15 in the formation of the WN film. That is, the WF ₆ gas is supplied from the source gas supply unit 35 to the vacuum chamber 21 over, for example, 2 seconds from the timing T21 to the timing T22. The WF ₆ gas is supplied into the vacuum chamber 21 at a flow rate of 20 sccm, for example. Thereby, the WF ₆ is adsorbed to almost the entire substrate S via the SiH ₄ on the substrate S.

When the WF ₆ gas is supplied, N ₂ gas is supplied from the inert gas supply unit 36 to the vacuum chamber 21 over, for example, 2 seconds from the timing T22 to the timing T23. Thus, WF ₆ in the vacuum chamber 21 is evacuated with _{N 2} gas.

When the N ₂ gas is exhausted, SiH ₄ gas as a reaction gas is supplied from the silane gas supply unit 31 to the vacuum chamber 21 for 4 seconds from timing T23 to timing T24, for example. SiH ₄ gas is supplied into the vacuum chamber 21 at a flow rate of, for example, 70 sccm. As a result, WF ₆ adsorbed on the substrate S reacts with SiH ₄ to form a several atomic layer WSi film on the substrate S.

When the WSi film is formed, N ₂ gas is supplied from the inert gas supply unit 33 to the vacuum chamber 21 for 2 seconds from timing T24 to timing T25, for example. Thereby, SiH ₄ in the vacuum chamber 21 is exhausted together with the N ₂ gas.

  The cycle from the timing T21 to the timing T25 is one cycle, and the film formation cycle is repeated a predetermined number of times, whereby a WSi film having a predetermined film thickness is formed. Note that the timing T21 in the first cycle corresponds to the timing T4.

[Formation of WSiN film]
When the WSiN film is formed, as shown in FIG. 6, various gases are supplied from timing T31 to timing T35 in the same manner as from timing T11 to timing T15 in the formation of the WN film. That is, the WF ₆ gas is supplied from the source gas supply unit 35 to the vacuum chamber 21 over, for example, 2 seconds from the timing T31 to the timing T32. The WF ₆ gas is supplied into the vacuum chamber 21 at a flow rate of 20 sccm, for example. As a result, the WF ₆ is adsorbed to the substrate S via the SiH ₄ on the substrate S.

When the WF ₆ gas is supplied, N ₂ gas is supplied from the inert gas supply unit 36 to the vacuum chamber 21 over, for example, 2 seconds from timing T32 to timing T33. Thus, WF ₆ in the vacuum chamber 21 is evacuated with _{N 2} gas.

When the N ₂ gas is exhausted, SiH ₄ gas as a reaction gas is supplied from the silane gas supply unit 31 to the vacuum chamber over, for example, 4 seconds from timing T33 to timing T34. SiH ₄ gas is supplied into the vacuum chamber 21 at a flow rate of, for example, 70 sccm. As a result, WF ₆ adsorbed on the substrate S reacts with SiH ₄ to form a several atomic layer WSi film on the substrate S.

When the WSi film is formed, N ₂ gas is supplied from the inert gas supply unit 33 to the vacuum chamber 21 over, for example, 2 seconds from timing T34 to timing T35. Thereby, SiH ₄ in the vacuum chamber 21 is exhausted together with the N ₂ gas.

When evacuation with N ₂ gas is performed, supply of NH ₃ gas as a reaction gas from the nitriding gas supply unit 32 to the vacuum chamber 21 is started at timing T35. For example, at timing T36 two seconds later, NH ₃ gas is supplied. ₃ Gas supply is stopped. NH ₃ gas is supplied into the vacuum chamber 21 at a flow rate of 5 sccm, for example. Thereby, the WSi monoatomic film is nitrided to form a WSiN film of several atomic layers on the substrate S.

When WSiN film is formed, at the timing T36, the supply of _{N 2} gas into the vacuum chamber 21 is started from the inert gas supply unit 34, for example, at the timing T37 after 2 seconds, the supply of _{N 2} gas Stopped. Thereby, NH ₃ in the vacuum chamber 21 is exhausted together with the N ₂ gas.

  The cycle from timing T31 to timing T37 is one cycle, and the film formation cycle is repeated a predetermined number of times, thereby forming a WSiN film having a predetermined film thickness. Note that the timing T31 in the first cycle corresponds to the timing T4.

  As described above, even when any of the WN film, the WSi film, and the WSiN film is formed, the hydrogen plasma supply process and the silane gas supply process, which are pretreatment processes, are performed before forming these films. Yes.

Moreover, in the silane gas supply process, the supply time of the SiH ₄ gas is longer than the reaction gas supplied into the vacuum chamber 21 in each reaction gas supply process. Thereby, the number of particles of SiH ₄ reaching the surface of the substrate S in the silane gas supply step is larger than the number of particles reaching the surface of the substrate S in each reaction gas supply step. Therefore, the surface of the substrate S after the silane gas supply process is more likely to contain a gas that can react with WF _{6 than} the surface of the substrate S after the reaction gas supply process. Therefore, as compared with the case where the silane gas supply process is not performed, the probability that WF ₆ is adsorbed to the entire substrate S is increased, so that the incubation time can be shortened. Therefore, the WN film, the WSi film, and the WSiN film can be formed without causing the incubation time even at the substrate temperature that would cause the incubation time unless the pretreatment is performed.

  Thus, when the tungsten compound film is formed on the substrate S in the film forming chamber 15, the substrate S is transferred from the film forming chamber 15 to the seed layer forming chamber 16 by the transfer robot 11a. In the seed layer forming chamber 16, a Cu film is formed on the tungsten compound film.

  When the Cu film is formed on the substrate S in the seed layer forming chamber 16, the substrate S is transported from the seed layer forming chamber 16 to the unloading chamber 13 by the transport robot 11a, and the substrate S is transported to the unloading chamber. 13 to the outside.

[Semiconductor device]
The substrate S is unloaded from the multi-chamber type film forming apparatus 10 and then transferred to an apparatus for performing electroplating. In the apparatus, an electroplating process is performed on the substrate S, so that the substrate S is in a hole. Copper wiring is formed on the substrate.

  Then, after such electrolytic plating treatment, various treatments such as CMP treatment for copper wiring, formation of a protective film for protecting the surface of the substrate S, and adhesion to other element substrates are performed on the substrate S. Thus, a semiconductor device having the tungsten compound film is formed.

  When the tungsten compound film is formed, since the incubation time is shortened as described above, the semiconductor device has a tungsten compound film with improved film characteristics such as film density and barrier properties.

[Second Embodiment]
Hereinafter, a second embodiment that embodies the method for forming a tungsten compound film according to the present disclosure and a second embodiment that embodies the semiconductor device of the present invention will be described with reference to FIGS. 1 and 7. Note that the tungsten compound film forming method in the second embodiment is compared with the tungsten compound film forming method in the first embodiment, and the pre-processing performed before the tungsten compound film is formed and the processing are performed. The configuration of the pretreatment chamber 14 is different. Therefore, in the following, this difference will be mainly described.

[Configuration of multi-chamber deposition system]
As shown in FIG. 1, the pre-processing chamber 14 of the multi-chamber type film forming apparatus 10 is a plasma processing chamber that generates plasma from an inert gas such as argon (Ar) gas in addition to the H ₂ gas. It is. Pretreatment chamber 14, for example, a high-frequency power frequency is 13.56MHz to supply to each of the _{H 2} gas, and Ar gas, creating a plasma from each of the _{H 2} gas and Ar gas.

[Tungsten compound film formation by multi-chamber type film forming system]
The operation when forming the tungsten compound film, which is one of the operations of the multi-chamber type film forming apparatus 10, will be described with reference to FIG.
When a tungsten compound film is formed by the multi-chamber type film forming apparatus 10, first, the substrate S before processing is carried into the carry-in chamber 12 by an external transfer robot, as in the first embodiment. When the substrate S is loaded into the loading chamber 12, the substrate S is loaded into the pretreatment chamber 14 by the transfer robot 11a.

  Next, in the pretreatment chamber 14, as shown in FIG. 7, at timing T41, supply of Ar gas and supply of high-frequency power to the Ar gas are started. As a result, the plasma generated from the Ar gas is supplied to the surface of the substrate S, whereby irregularities are formed on the surface. When such an inert gas plasma supply process is continued for a predetermined time, for example, 60 seconds, the supply of Ar gas is stopped at timing T42.

Similarly, at timing T42, supply of H ₂ gas is started, and thereby plasma generated from H ₂ gas is supplied to the substrate S. Thereby, excited species containing hydrogen are adsorbed on the surface of the substrate S. When supply of plasma generated from H ₂ gas is continued for a predetermined time, for example, 60 seconds, supply of H ₂ gas and high-frequency power is stopped at timing T43.

When the supply of H ₂ plasma is completed, the substrate S is transferred from the pretreatment chamber 14 to the film forming chamber 15 by the transfer robot 11a.
When the substrate S is carried into the film forming chamber 15, the supply of SiH ₄ gas from the silane gas supply unit 31 to the vacuum chamber 21 is started at timing T 44, as in the first embodiment, for example, after 60 seconds. At timing T45, the supply of SiH ₄ gas is stopped.

After such a pretreatment process including supply of inert gas plasma, supply of H ₂ plasma, and supply of silane gas, any one of the WN film, the WSi film, and the WSiN film is performed in the same manner as in the first embodiment. Are formed on the substrate S.

Thus, in this embodiment, before supplying hydrogen plasma and silane gas to the substrate S, inert gas plasma is supplied. Therefore, when plasma of H ₂ gas or SiH ₄ gas is supplied to the substrate S, irregularities are formed on the surface of the substrate S. This makes it easier for the particles supplied to the surface of the substrate S to be adsorbed by supplying H ₂ plasma or silane gas. Moreover, since the surface area of the substrate S increases due to the irregularities, the contact area between the substrate S and the tungsten compound film also increases. Therefore, the substrate S and the tungsten compound film are more likely to be in close contact with each other.

[Test example]
[Incubation time]
While heating a silicon substrate having a diameter of 8 inches to 160 ° C., supply of plasma generated from H ₂ gas and supply of SiH ₄ gas were performed under the following conditions.
[Condition 1: Supply of H ₂ plasma]
・ H ₂ gas flow rate 200sccm
-Pressure in the pretreatment chamber 37 Pa
・ High frequency power 200W
Processing time 60 seconds [Condition 2: Supply of SiH ₄ gas]
・ SiH ₄ gas flow rate 70sccm
・ Pressure in the vacuum chamber 21Pa
・ Processing time 60 seconds

Thereafter, supply of WF ₆ gas (step 1), supply of N ₂ gas (step 2), supply of SiH ₄ gas (step 3), supply of N ₂ gas (step 4), supply of WF ₆ gas (step 5) ), N ₂ gas supply (step 6), NH ₃ gas supply (step 7), and N ₂ gas supply (step 8), thereby forming a WN film. Each step was performed under the conditions shown in Table 1 below.

  The relationship between the thickness of the WN film formed under these conditions and the number of cycles is shown by a solid line in FIG. As shown in FIG. 8, it was recognized that a WN film can be formed from one cycle, that is, a WN film can be formed without causing an incubation time. When forming the WN film under the above conditions, it was confirmed that the incubation time does not occur if the temperature of the silicon substrate is 150 ° C. or higher.

In addition, while a silicon substrate having a diameter of 8 inches was heated to 160 ° C. and plasma generated from NH ₃ gas was supplied, a WN film was formed by the cycle constituted by steps 1 to 8 above. The generation of plasma from NH ₃ gas was performed under the following conditions.
[Condition 3: Supply of NH ₃ plasma]
・ NH ₃ gas flow rate 200sccm
-Pressure in the pretreatment chamber 37 Pa
・ High frequency power 200W
・ Processing time 60 seconds

  The relationship between the thickness of the WN film formed under such conditions and the number of cycles is shown in FIG. As shown in FIG. 8, it was recognized that the WN film was formed only after 9 cycles. Under these conditions, if the temperature of the silicon substrate is 210 ° C. or higher, the incubation time does not occur. On the other hand, when the temperature is 200 ° C., the WN film is formed in three cycles and the temperature is 180 ° C. It was observed that sometimes a WN film was formed in 6 cycles.

In addition, in the case where only the SiH ₄ gas is supplied before the WN film is formed by the ALD method composed of the above 1 to 8 steps, the incubation is performed if the temperature of the silicon substrate is 190 ° C. or higher. It was observed that no time was generated. Note that before the supply of the SiH ₄ gas, even if the supply of the plasma generated from the NH ₃ gas, as in the case of performing only the supply of the SiH ₄ gas, if the temperature of the silicon substrate 190 ° C. or higher It was also observed that no incubation time occurred.

Further, even when the WSi film and the WSiN film are formed by the ALD method, when SiH ₄ gas is supplied as a pretreatment, silicon that does not cause incubation time is generated as compared with the case of supplying NH ₃ plasma. It was confirmed that the minimum temperature of the substrate was low. Further, even when the WSi film and the WSiN film are formed by the ALD method, when the supply of H ₂ plasma and the supply of SiH ₄ gas are performed as pretreatment, only the supply of SiH ₄ gas is performed. It was found that the lower limit temperature at which the incubation time does not occur is lower.

[Step coverage of WN film]
A plurality of holes having an opening diameter of 5.7 μm and a depth of 51 μm are formed on a silicon substrate having an 8 inch diameter, and an insulating film is formed on the surface of the silicon substrate and the inner wall surface of the hole. Formed. After supplying plasma generated from H ₂ gas and SiH ₄ gas to the silicon substrate, a WN film was formed using the ALD method. The supply of H ₂ plasma was performed under the above condition 1, and the supply of SiH ₄ gas was performed under the above condition 2. Further, the WN film was formed so that the thickness on the surface of the silicon substrate was 18 nm by repeating the cycle composed of Step 1 to Step 45 45 times.

  The WN film thus formed is shown in FIG. As shown in FIG. 9, the surface film thickness Th1 on the surface of the silicon substrate is 18 nm, the side film thickness Th2 on the side surface of the hole is 15 nm, and the bottom film thickness Th3 on the bottom surface of the hole is 13 nm. It was. That is, it was recognized that the side coverage as the side film thickness Th2 with respect to the surface film thickness Th1 was 83%, and the bottom coverage as the bottom film thickness Th3 with respect to the surface film thickness Th1 was 72%.

  Even when the WSi film and the WSiN film were formed by the ALD method, it was confirmed that both the side coverage and the bottom coverage were equivalent to the WN film.

Hereinafter, according to the first embodiment and the second embodiment of the present invention, the effects listed below can be obtained.
(1) In the first embodiment and the second embodiment, before the tungsten compound film is formed on the substrate S by supplying the WF ₆ gas, the NH ₃ gas, and the SiH ₄ gas, the SiH is applied to the substrate S. _Four gases are supplied. Moreover, the number of SiH ₄ gas particles supplied to the substrate S is larger than the number of reaction gas particles supplied to the substrate S in a single reaction gas supply step. Thus, the surface of the substrate S after the silane gas supply step has a higher probability that a gas capable of reacting with the WF ₆ gas exists as compared with the surface of the substrate S after the reaction gas supply step. Therefore, as compared with the case where the silane gas supply process is not performed, the probability that WF ₆ is adsorbed to the entire substrate S is increased, and as a result, the incubation time can be shortened. Therefore, when the silane gas supply step is not performed, it is possible to form the tungsten compound film without causing the incubation time even at the substrate temperature that causes the incubation time.

(2) In the first and second embodiments, the plasma generated from the H ₂ gas is supplied to the substrate S prior to the supply of the SiH ₄ gas. As a result, the incubation time can be made shorter than when only the SiH ₄ gas is supplied before the WF ₆ gas and the reactive gas are supplied.

(3) In the first embodiment and the second embodiment, the supply stop of SiH ₄ gas and the start of supply of WF ₆ gas in the silane gas supply step are performed at the same time. Therefore, when WF ₆ gas is supplied, There is a high possibility that more SiH ₄ is adsorbed on the substrate S than thereafter. Therefore, the tungsten compound film is easily formed on the entire substrate S from the start of the formation of the tungsten compound film.

(4) In the first embodiment and the second embodiment, when the WN film is formed, W (NH) having higher reactivity with W than NH ₃ gas with respect to W reduced by SiH ₄ gas. _{2) F 5} is supplied. Therefore, W is easily nitrided even at a low temperature as described above.

(5) In the second embodiment, the plasma generated from the Ar gas is supplied onto the substrate S, whereby irregularities are formed on the surface of the substrate. According to such unevenness, the probability of adsorption of excited species of hydrogen and SiH ₄ supplied on the substrate S is increased, so that only plasma generated from H ₂ gas is supplied prior to supply of SiH ₄ gas. However, the SiH ₄ gas is more easily adsorbed to the substrate S. This makes the incubation time shorter.

(6) In the first and second embodiments, the incubation time is shortened when the tungsten compound film is formed. Therefore, the tungsten compound film is easily formed in the entire region of the tungsten compound film in the semiconductor device from the start of the formation of the tungsten compound film. Therefore, the semiconductor device has a tungsten compound film with improved film characteristics such as film density and barrier property.
In addition, each said embodiment can also be suitably changed and implemented as follows.

The flow rate of SiH ₄ gas in the silane gas supply process is larger than the flow rate of reaction gas in the reaction gas supply process, and the supply time of SiH ₄ gas is longer than the supply time of reaction gas in the reaction gas supply process . Not limited to this, in the silane gas supply step, (a) increasing the flow rate of SiH ₄ gas, (b) increasing the supply time of SiH ₄ gas, or (c) SiH than in the reaction gas supply step. You may make it perform a silane gas supply process on the conditions which satisfy | fill either of making the pressure of ₄ gas high. Moreover, you may make it perform a silane gas supply process on the conditions which satisfy | fills any two of (a)-(c), and the conditions which satisfy | fill all (a)-(c). In short, the number of SiH ₄ particles reaching the surface of the substrate S in the silane gas supply step may be larger than the number of reaction gas particles reaching the surface of the substrate S in each reaction gas supply step. . Even if it is such a structure, the effect according to said (1)-(6) can be acquired.

The plasma generated from the H ₂ gas is supplied to the surface of the substrate S prior to the supply of the SiH ₄ gas, but the supply of the H ₂ plasma may be omitted. Even if it is such a structure, the effect according to said (1) and (3)-(6) can be acquired.

The supply stop of SiH ₄ gas and the start of supply of WF ₆ gas in the silane gas supply process are performed simultaneously. However, the supply of WF ₆ gas is stopped after a predetermined time after the supply of SiH ₄ gas is stopped. May be started. Even if it is such a structure, the effect according to said (1), (2), (4)-(6) can be acquired.

In the second embodiment, Ar plasma and H ₂ plasma may be supplied to the substrate S simultaneously. Even if it is such a structure, the effect according to said (1)-(6) can be acquired.

  The formation of the WN film may be formed by sequentially repeating the source gas supply process and the nitriding gas supply process, or the source gas supply process, the reducing gas supply process, and the nitriding gas supply process are sequentially repeated. It may be formed. Even with such a configuration, the incubation time can be shortened by the amount of the pretreatment, and as a result, the temperature of the substrate where the incubation time does not occur can be lowered.

  The conditions such as the gas supply flow rate, the pressure in the processing chamber, and the processing time in each of the above steps are within a range in which a tungsten compound film can be formed, and the particles supplied to the substrate S in the silane gas supplying step are once In the reactive gas supply step, the number can be arbitrarily changed within a range that is larger than the number of particles supplied to the substrate S.

When using a gas other than silane gas in the reaction gas supply step, the number of SiH ₄ particles supplied to the surface of the substrate S in the silane gas supply step is supplied to the surface of the substrate S in the reaction gas supply step. It may be smaller than the number of reaction gas particles to be produced. Even with such a configuration, since the probability that WF ₆ gas is adsorbed on the surface of the substrate S is increased by the amount of SiH ₄ adsorbed on the surface of the substrate S, the incubation time can be shortened.

The multi-chamber type film forming apparatus 10 may have a processing chamber other than the above, or may not have a seed layer forming chamber.
Although the pretreatment chamber 14 is provided separately from the film formation chamber 15, the film formation chamber 15 is provided with a high frequency power source, an H ₂ gas supply unit, or an Ar gas supply unit, so that Processing may be performed. In this case, the pretreatment chamber 14 can be omitted.

In the pretreatment chamber 14, H ₂ plasma or Ar plasma is formed using high frequency power having a frequency of 13.56 MHz, but if plasma is generated from these gases, the frequency of the high frequency power or The configuration of the processing chamber 14 can be arbitrarily changed.

In the seed layer forming chamber 16, the Cu film may be formed not only by the sputtering method but also by a film forming method such as a CVD method or a PVD method other than sputtering.
The silane gas supply unit 31 and the nitriding gas supply unit 32 of the film forming chamber 15 may be connected to different pipes.

The gas used in the silane gas supply step and the reducing gas supply step is not limited to SiH ₄ gas, but may be silane gas represented by Si _n H _{2n + 2} , such as disilane (Si ₂ H ₆ ) gas.
The gas used in the inert gas supply step is not limited to N ₂ gas, but may be other inert gas such as Ar gas or helium gas.

The gas used in the source gas supply process may be a gas containing W other than WF ₆ gas, for example, tungsten hexachloride, tungsten oxyhalides such as WOF ₂ , WOF ₄ , WOCl ₂ , and WOCl ₄ Good.

As the gas used in the nitriding gas supply step, a gas containing N other than NH ₃ gas, for example, hydrazine gas (N ₂ H ₄ ) or a hydrazine derivative gas in which hydrogen in hydrazine is substituted with a hydrocarbon group is used. You may do it. In short, any gas capable of nitriding W may be used.

When the WN film, WSi film, and WSiN film are formed, the inert gas supply process is performed after the WF ₆ gas, SiH ₄ gas, or NH ₃ gas is supplied to the substrate S. Exhaust in the vacuum chamber 21 by only the exhaust part 25 may be performed without supplying the active gas.

  The tungsten compound film formed on the substrate S is not limited to a single layer of a WN film, a WSiN film, and a WSiN film, and any two of these tungsten compound films or the above three kinds of films are laminated. It may be a thing. In this case, the pretreatment described above may be performed when the tungsten compound film immediately above the substrate S is formed.

In the second embodiment, Ar plasma is supplied to the substrate S. However, plasma generated from an inert gas other than Ar, such as N ₂ gas or He gas, is supplied to the substrate S. May be.

The inert gas supply unit 33 is N with respect to the vacuum chamber 21 when NH ₃ gas is supplied from the nitriding gas supply unit 32 and when WF ₆ gas is supplied from the source gas supply unit 35. _Two gases may be supplied. Thus, NH ₃ gas and WF ₆ gas is suppressed to flow back into silane gas pipe side.

The inert gas supply unit 34 is N _{2 with} respect to the vacuum chamber 21 when SiH ₄ gas is supplied from the silane gas supply unit 31 and when WF ₆ gas is supplied from the source gas supply unit 35. Gas may be supplied. Thus, SiH ₄ gas and WF ₆ gas is suppressed to flow back into the nitriding gas pipe side.

The inert gas supply unit 36 is N _{2 with} respect to the vacuum chamber 21 when SiH ₄ gas is supplied from the silane gas supply unit 31 and when NH ₃ gas is supplied from the nitriding gas supply unit 32. Gas may be supplied. Thus, SiH ₄ gas and NH ₃ gas is suppressed to flow back into the fluorine-based gas pipe GL2 side.
-The board | substrate S does not need to have a support substrate.

  The target for the above pretreatment and the formation of the tungsten compound film was a silicon substrate having a through hole, and an insulating film made of a silicon oxide film was formed on the surface of the silicon substrate and in the through hole. However, the material for forming the insulating film formed on the silicon substrate may be a silicon nitride film and a metal boron oxide. Examples of the metal boron oxide include ZrBO, TaBO, TiBO, and HfBO. Can be mentioned. In addition, the formation target of the tungsten compound may be an insulating film and a recess formed in the insulating film. As the material for forming the insulating film, any of the above materials can be used. And even if the insulating film is formed from any of these materials, according to the pretreatment, an effect equivalent to that when the formation target is a silicon substrate on which a silicon oxide film is formed can be obtained. The material for forming the tungsten compound film may be a silicon substrate on which the insulating film as described above is not formed, another semiconductor substrate, or the like.

Note that when H ₂ plasma and silane gas are supplied to the insulating film, the surface of the insulating film is terminated with hydrogen, and thus SiH ₄ is easily adsorbed to the insulating film. It is considered a thing.

  DESCRIPTION OF SYMBOLS 10 ... Multi chamber type film-forming apparatus, 11 ... Transfer chamber, 11a ... Transfer robot, 12 ... Carry-in chamber, 13 ... Unload chamber, 14 ... Pretreatment chamber, 15 ... Film-forming chamber, 16 ... Seed layer chamber, 21 ... Vacuum Tank, 21a ... Bottom wall, 21b ... Upper wall, 22 ... Substrate stage, 23 ... Heater, 24 ... Heater power supply, 25 ... Exhaust part, 26 ... Shower plate, 26a ... Opening part, 31 ... Silane gas supply part, 32 ... Nitriding Gas supply unit, 33, 34, 36 ... inert gas supply unit, 35 ... raw material gas supply unit, GL1 ... hydrogen gas pipe, GL2 ... fluorine gas pipe, P1 ... exhaust port, P2 ... gas supply port, S ... substrate.

Claims (7)

A silane gas supply step in which silane gas is supplied to the substrate;
A source gas supply step in which a source gas containing tungsten is supplied to the substrate;
A reaction gas supply step in which a reaction gas that reacts with tungsten is supplied to the substrate;
In the silane gas supply step, more silane gas particles than the reaction gas particles that reach the surface of the substrate in one reaction gas supply step reach the surface of the substrate,
After the silane gas supply step, the source gas supply step and the reaction gas supply step are repeatedly performed at different timings, whereby a tungsten compound film is formed on the substrate. Forming method. Before the silane gas supply step,
The method for forming a tungsten compound film according to claim 1, further comprising a hydrogen plasma supply step in which plasma generated from hydrogen gas is supplied to the substrate. By the end of the hydrogen plasma supply process,
The method for forming a tungsten compound film according to claim 2, further comprising an inert gas plasma supply step in which plasma generated from an inert gas is supplied to the substrate. Stopping supply of the silane gas in the silane gas supply step;
The method for forming a tungsten compound film according to any one of claims 1 to 3, wherein supply of the source gas in the source gas supply step performed following the silane gas supply step is simultaneously performed. The source gas supply step includes a first source gas supply step and a second source gas supply step,
The reaction gas supply step includes:
A reducing gas supply step in which a silane gas for reducing tungsten is supplied;
A nitriding gas supply step in which a nitriding gas for nitriding tungsten is supplied to the substrate;
Each of the first source gas supply step, the reaction gas supply step, the reducing gas supply step, and the second source gas supply step is sequentially performed at different timings, whereby the tungsten is formed on the substrate. The tungsten nitride film which is a compound film is formed. The formation method of the tungsten compound film as described in any one of Claims 1-4. A silane gas supply step in which silane gas is supplied to the substrate;
A source gas supply step in which a source gas containing tungsten is supplied to the substrate;
A reaction gas supply step in which a reaction gas other than the silane gas that reacts with the tungsten is supplied to the substrate,
After the silane gas supply step, the source gas supply step and the reaction gas supply step are repeatedly performed at different timings, whereby a tungsten compound film is formed on the substrate. Forming method. A semiconductor device having a tungsten compound film,
The said tungsten compound film is formed using the formation method of the tungsten compound film as described in any one of Claims 1-6.