Patent Application
20240105445
This application is based upon and claims the benefit of priority from Japanese Patent Application Nos. 2022-155501 and 2023-035971, filed on Sep. 28, 2022, and Mar. 8, 2023, respectively, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a film forming method and a substrate processing system.
For example, when embedding a ruthenium film in a recess formed in an insulating layer, in Patent Documents 1 and 2, if a natural oxide film is formed on the surface of a tungsten layer exposed from the recess, it is proposed to remove the natural oxide film and then to fill the recess with the ruthenium film.
For example, in Patent Document 3, it is proposed to form a Ti—Si layer on the top surface of a Borophosphosilicate glass (BPSG) layer formed on a silicon substrate surface, to laminate a TiN—Ti-based barrier metal layer on the Ti—Si layer, and to form an electrode wire on the barrier metal layer. It is described that the Ti film of the barrier metal layer, which adheres to the BPSG layer, absorbs O of SiO2, which is the main portion of the BPSG layer, thereby being turned into TiO2.
According to one embodiment of the present disclosure, there is provided a film forming method including: preparing, on a stage, a substrate having an insulating layer in which a recess defined by an upper portion, a side wall portion, and a bottom portion is formed, and a tungsten layer exposed from the bottom portion of the recess; removing a tungsten oxide film, which has been formed by oxidizing the tungsten layer at the bottom portion, by supplying TiCl4 gas to at least the bottom portion of the recess; and embedding a ruthenium film in the recess after removing the tungsten oxide film.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.
Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, systems, and components have not been described in detail so as not to unnecessarily obscure aspects of the various embodiments.
In each of the drawings, the same components may be denoted by the same reference numerals, and redundant descriptions thereof may be omitted.
In a film structure in which a tungsten layer is exposed at the bottom of a recess formed in an insulating layer such as a silicon nitride film (SiN) or silicon oxide film (SiO2), there is a process of embedding a ruthenium film in the recess.
Since the ruthenium film embedded in the recess functions as a metal wire, the material of the bottom of the recess to be in contact with the ruthenium film is preferably a material having as low a resistance as possible. On the other hand, the tungsten layer used as the material for the bottom of the recess is a material that is easily oxidized, and the surface of the tungsten layer is easily oxidized and is turned into a tungsten oxide film (WOx). When the ruthenium film is formed on the tungsten oxide film, since the tungsten oxide film is an insulator, the resistance becomes high at the contact portion with the ruthenium film. Therefore, it is preferable to remove the tungsten oxide film at the bottom of the recess and to use a low-resistance tungsten layer as the material for the bottom of the recess. Therefore, first and second embodiments provide a film forming method that is capable of effectively removing a tungsten oxide film before embedding a ruthenium film in a recess.
A film forming method according to the first embodiment will be described with reference to
In the film forming method according to the first embodiment illustrated in
Next, in step S2, TiCl4 gas is supplied into the first processing chamber. Then, the tungsten oxide film 101 is removed by the TiCl4 gas supplied to at least the bottom portion of the recess 120 in the substrate. As a result, the tungsten oxide film 101 exposed at the bottom portion of the recess 120 is removed, as illustrated in
An example of process conditions for step S2 is provided.
<Removal of WOx by TiCl4 Gas: Process Conditions>
Typical conditions may include 460 degrees C., 9 Torr (1,200 Pa), and TiCl4/Ar of 90/1,000 sccm. However, the present disclosure is not limited thereto.
Next, in step S3, the substrate from which the tungsten oxide film 101 has been removed is prepared by vacuum-transferring the substrate from the first processing chamber to a processing chamber (referred to as a “second processing chamber”) configured to embed a ruthenium film and placing the substrate on the stage within the second processing chamber. As will be described later, the first processing chamber and the second processing chamber are connected to a vacuum transfer chamber so that the substrate can be transferred between the first processing chamber and the second processing chamber without breaking the vacuum by a transfer device within the vacuum transfer chamber.
Next, in step S4, a ruthenium-containing raw material gas and CO gas are supplied to embed ruthenium (Ru) in the recess 120, and the processing is terminated. The ruthenium-containing raw material gas is simultaneously supplied with the CO gas as a carrier gas. As a result, as illustrated in
An example of process conditions for step S4 is provided.
<Film Formation of Ru Layer: Process Conditions>
Typical conditions may include 156 degrees C., 20 mTorr (2.666 Pa), and CO of 350 sccm. However, the present disclosure is not limited thereto.
The ruthenium-containing raw material gas is any of a gas containing Ru3(CO)12, (2,4-dimethylpentadienyl)(ethylcyclopentadienyl)ruthenium: (Ru(DMPD)(EtCp)), bis(2,4-dimethylpentadienyl)Ruthenium: (Ru(DMPD)2), 4-dimethylpentadienyl)(methylcyclopentadienyl)Ruthenium: (Ru(DMPD)(MeCp)), Bis(Cyclopentadienyl)Ruthenium: (Ru(C5H5)2), Cis-dicarbonylbis(5-methylhexane-2,4-dionate)ruthenium(II), bis(ethylcyclopentadienyl)Ruthenium(II): Ru(EtCp)2, or the like may be used.
As a result, the ruthenium film 130 is formed in a bottom-up manner from the bottom portion of the recess 120, as illustrated in
In a ruthenium embedding method of the related arts, the tungsten oxide film 101 at the bottom portion of the recess 120 may remain due to reoxidation or the like, and a ruthenium film 130 may be formed on the tungsten oxide film 101. Therefore, the tungsten oxide film, which is an insulator, increases the resistance at the contact portion of the ruthenium film 130 (a wiring layer).
In contrast, the film forming method according to the first embodiment includes: a process of preparing, on the stage of the first processing chamber, a substrate having an insulating layer 110 in which a recess 120 defined by an upper portion, a side wall portion, and a bottom portion is formed, and a tungsten layer 100 exposed from the bottom portion of the recess 120; a process of supplying TiCl4 gas to at least the bottom portion of the recess 120 to remove a tungsten oxide film 101 formed due to oxidation of the tungsten layer 100 from the bottom portion of the recess 120; and a process of embedding a ruthenium film 130 in the recess 120 after removing the tungsten oxide film 101.
With the film forming method according to the first embodiment, the ruthenium film 130 is formed on the tungsten layer 100 at the bottom portion of the recess 120 after effectively removing the tungsten oxide film 101 with TiCl4 gas. As a result, metal wiring by the ruthenium film 130 having low resistance to the tungsten layer 100 becomes possible.
The temperature condition for removing the tungsten oxide film 101 with TiCl4 gas in the first processing chamber (step S2) is 300 degrees C. to 600 degrees C. On the other hand, the temperature condition during the formation of the ruthenium film 130 in the second processing chamber (step S4) is 100 degrees C. to 300 degrees C. Therefore, since the temperature zones to be controlled in step S2 and step S4 are different from each other, the first processing chamber and the second processing chamber may be implemented as separate processing chambers.
Next, a film forming method according to the second embodiment will be described with reference to
In the film forming method according to the second embodiment illustrated in
Next, in step S12, TiCl4 gas is supplied into the first processing chamber. Then, the tungsten oxide film 101 is removed by the TiCl4 gas supplied to at least the bottom portion of the recess 120 in the substrate. As a result, the tungsten oxide film 101 exposed at the bottom portion of the recess 120 is removed. Since the process conditions of step S12 are the same as the process conditions of step S2 in
However, a case where the tungsten oxide film 101 cannot be completely removed or a case where the tungsten layer 100 is re-oxidized may occur. For example, even if the tungsten oxide film 101 were removable by supplying TiCl4 gas, there is a case where the tungsten layer 100 exposed from the bottom portion of the recess 120 is re-oxidized during the transfer from the first processing chamber to the second processing chamber and a tungsten oxide film 101 is formed.
In addition, in step S12, due to the use of TiCl4 gas, there is a case where titanium and/or titanium oxide is generated as a reaction by-product and remains as a residue on the surfaces of the tungsten oxide film 101 and the tungsten layer 100 exposed from the bottom portion of the recess 120. The reaction by-product of titanium and/or the titanium oxide remaining as the residue causes an increase in resistance at the contact portion between the ruthenium film 130 and the tungsten layer 100. Due to these multiple factors, the tungsten oxide film 101 may remain on the surface layer of the bottom portion of the recess 120, as illustrated in
Therefore, in the film forming method according to the second embodiment, the titanium film 102 is formed on the remaining tungsten oxide film 101 in the next step S13.
An example of process conditions for step S13 is provided.
<Film Formation of Ti Film: Process Conditions>
Typical conditions may include 460 degrees C., 5 Torr (666.6 Pa), TiCl4/Hz/NH3/Ar of 25/20/900/1,200 sccm, and RF power of 300 W. However, the present disclosure is not limited thereto.
As a result, a titanium film 102 is formed on the exposed tungsten oxide film 101 by plasma of gases of TiCl4, Hz, NH3 and Ar, as illustrated in
In addition, since the titanium film 102 adheres to the tungsten oxide film 101 (
Next, in step S14, the remaining titanium film 102 is modified into a titanium oxide film 103. The modification of the titanium film 102 into the titanium oxide film 103 effectively prevents the tungsten layer 100 from being re-oxidized during the transfer of the substrate to the second processing chamber for forming a ruthenium film.
An example of process conditions for step S14 is represented.
<Oxidation of Ti Film: Process Conditions>
However, the gas is not limited to 02 gas, and may be O3 gas), and RF power may be supplied to generate oxygen (O) plasma. That is, plasma may be either of being present or absent.
Typical conditions may include 460 degrees C., 5 Torr (666.6 Pa), and O2 of 1,000 sccm. However, the present disclosure is not limited thereto.
In addition, there is a possibility that in step S13, Ti absorbs O from the tungsten oxide (WOx) film 101, so that all of the titanium film 102 will be modified into the titanium oxide film 103. In addition, there is also a possibility that all of the titanium film 102 is modified into the titanium oxide film 103 during transfer from the first processing chamber to the second processing chamber. In that case, it may be considered to omit the processing of step S14.
However, there may also be a case where not all of the titanium film 102 is necessarily modified into the titanium oxide film 103. In some cases, the titanium oxide film 103 and the titanium film 102 may be alternately laminated in three or more stages. In this case, only the uppermost titanium oxide film 103 is removed in the step of removing the titanium oxide film 103 (S16), which will be described later, and the titanium oxide film 103 existing under the titanium film 102 cannot be removed. Therefore, in order to remove all of the titanium oxide film 103 on the tungsten layer 100 in the step of removing the titanium oxide film 103, which will be described later, and then embed a ruthenium film, it is preferable to execute the oxidation of the titanium film 102 in step S14. As a result, all of the titanium film 102 can be modified into the titanium oxide film 103.
In step S15, the substrate in the state in which the titanium film 102 in
Next, in step S16, the titanium oxide film 103 is removed by supplying Cl2 gas to at least the bottom portion of the recess 120 in the second processing chamber.
<Removal of TiOx Layer: Process Conditions>
Typical conditions may include 156 degrees C., 500 mTorr (66.66 Pa), and Cl2/Ar of 6/400 sccm. However, the present disclosure is not limited thereto.
In step S16, a chemical reaction represented by chemical reaction formula (1) is caused by plasma of Cl2 gas.
TiO(s)+Cl2(g)→TiOCl2(g) (1)
As a result, the titanium oxide film 103 reacts with chlorine is turned into TiOCl2 gas, which is volatilized, and the titanium oxide film 103 is removed as illustrated in
In the above, the titanium oxide film is removed by generating plasma from Cl2, but the same effect may be obtained by supplying Cl2 gas without generating plasma.
Next, in step S17, a ruthenium-containing raw material gas and a CO gas are supplied to the bottom portion of the recess 120 from which the titanium oxide film 103 has been removed, to embed ruthenium (Ru) in the recess 120, and the processing is terminated. A raw material gas for embedding ruthenium is simultaneously supplied with CO gas as a carrier gas. As a result, as illustrated in
Since the process conditions and the types of ruthenium-containing raw material gases in step S17 are the same as the process conditions and the exemplified types of ruthenium-containing material gases in step S4 of
The film forming method according to the second embodiment is a film forming method for embedding a ruthenium film 130 in a recess 120. The film method includes: a process of preparing a substrate having an insulating layer 110 having a recess 120 defined by an upper portion, a side wall portion, and a bottom portion, and a tungsten layer 100 exposed from the bottom portion of the recess 120 on a stage; and a process of forming a titanium film 102 on the tungsten layer 100 exposed from the bottom portion of the recess 120 before embedding the ruthenium film 130 in the recess 120. The titanium film 102 suppresses oxidation of the tungsten layer 100 exposed from the bottom portion of the recess 120.
This causes the titanium film 102 to act as an oxidation suppressing layer for the tungsten layer 100, and the substrate can be vacuum-transferred from the first processing chamber to the second processing chamber in the state in which the tungsten layer 100 is capped with the titanium film 102. As a result, the substrate can be transferred to the second processing chamber without forming a tungsten oxide film 101.
According to the film forming method of the second embodiment, after the substrate is transferred to the second processing chamber, the titanium oxide film 103 is removed and then the ruthenium film 130 is formed on the tungsten layer 100 at the bottom portion of the recess 120. As a result, the ruthenium film 130 can be formed on the tungsten layer 100 at the bottom portion of the recess 120 without any titanium oxide or titanium residue. Therefore, metal wiring by the ruthenium film 130 having low resistance to the tungsten layer 100 becomes possible.
The temperature conditions during the removal of the tungsten oxide film 101 by TiCl4 gas in the first processing chamber (step S12), during the formation of the titanium film 102 (step S13), and during the oxidation of the titanium film 102 (step S14) are 300 degrees C. to 600 degrees C. On the other hand, the temperature conditions during the removal of the titanium oxide film 103 (step S16) and during the formation of the ruthenium film 130 (step S17) in the second processing chamber are 100 degrees C. to 500 degrees C. and 100 degrees C. to 300 degrees C., respectively. Therefore, since the temperature zones to be controlled in steps S12 to S14, step S16, and step S17 are different from each other, the first processing chamber and the second processing chamber may be implemented as separate processing chambers.
Next, a film forming method according to a third embodiment will be described with reference to
In the film forming method of the third embodiment illustrated in
In the film forming method according to the second embodiment illustrated in
However, the tungsten oxide (WOx) film 101 may not be completely reduced by performing steps S12 to S14 only once. In this case, as illustrated in
Therefore, in the film forming method according to the third embodiment, when the tungsten oxide film 101 is not completely reduced after steps S12 to S14 are performed, the step of reducing WOx and the step of removing TiO 2 are repeated to completely remove the tungsten oxide film 101. Specifically, in step S20 of
When it is determined in step S20 that the set number of repetitions has not been performed, the process proceeds to step S21, in which Cl2 gas and Ar gas are supplied to at least the bottom portion of the recess 120 in the first processing chamber to remove the titanium oxide film 103 (see
When it is determined in step S20 that the set number of repetitions has been performed, the process proceeds to step S15 and the substrate is vacuum-transferred to the second processing chamber. The processing of steps S16 and S17 executed in the second processing chamber is the same as the processing of the same-numbered steps in film formation according to the second embodiment, and therefore the description thereof is omitted here.
In the film forming method according to the third embodiment, the processing of steps S12 to S14 is repeated a preset number of times (
In the film forming methods according to the second and third embodiments, the gas used for forming a Ti film in the processing of step S13 was a mixed gas of TiCl4, H2, NH3, and Ar (
In addition, in the film forming methods according to the second and third embodiments, O2 gas is used to oxidize the Ti film in the processing of step S14 (
A configuration example of a substrate processing system including two or more processing chambers will be described below with reference to
The substrate processing system 1 includes a plurality of processing chambers 11 to 14, a vacuum transfer chamber 20 connected to the plurality of processing chambers 11 to 14 and configured to vacuum-transfer a substrate W to the plurality of processing chambers 11 to 14, and a controller 70.
Although the example of the substrate processing system 1 illustrated in
The substrate processing system 1 further includes load-lock chambers 31 and 32, an atmospheric transfer chamber 40, load ports 51 to 53, gate valves 61 to 68, and a controller 70. The processing chamber 11 includes a stage 11a on which a substrate (hereinafter, referred to as “substrate W”) (e.g., a semiconductor wafer) is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 61. Similarly, the processing chamber 12 includes a stage 12a on which a substrate W is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 62. The processing chamber 13 includes a stage 13a on which a substrate W is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 63. The processing chamber 14 includes a stage 14a on which a substrate W is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 64. The interior of each of the processing chambers 11 to 14 is depressurized to a predetermined vacuum (depressurized) atmosphere, and a desired processing (e.g., etching, film formation, cleaning, or ashing) is performed on a substrate W in the interior. The operations of respective parts for executing the processes in the processing chambers 11 to 14 are controlled by the controller 70.
The interior of the vacuum transfer chamber 20 is depressurized to a predetermined vacuum (depressurized) atmosphere. In addition, a transfer mechanism 21 is provided in the vacuum transfer chamber 20. The transfer mechanism 21 transfers substrates W to the processing chambers 11 to 14 and the load-lock chambers 31 and 32. The operation of the transfer mechanism 21 is controlled by the controller 70.
The load-lock chamber 31 includes a stage 31a on which a substrate W is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 65 and to the atmospheric transfer chamber 40 through the gate valve 67. Similarly, the load-lock chamber 32 includes a stage 32a on which a substrate W is placed, and is connected to the vacuum transfer chamber 20 through the gate valve 66 and to the atmospheric transfer chamber 40 through the gate valve 68. The interior of each of the load-lock chambers 31 and 32 is configured to be switchable between an air atmosphere and a vacuum (depressurized) atmosphere. In addition, the switching between the vacuum (depressurized) atmosphere and the air atmosphere in the load-lock chambers 31 and 32 is controlled by the controller 70.
The interior of the atmospheric transfer chamber 40 is the air atmosphere, and, for example, a downflow of clean air is formed in the atmospheric transfer chamber 40. In addition, the atmospheric transfer chamber 40 is provided with a transfer mechanism 41. The transfer mechanism 41 transfers substrates W to the load-lock chambers 31 and 32 and carriers C in the load ports 51 to 53. The operation of the transfer mechanism 41 is controlled by the controller 70.
The load ports 51 to 53 are provided in the wall of a long side of the atmospheric transfer chamber 40. A carrier C, in which substrates W are accommodated, or an empty carrier C is mounted in each of the load ports 51 to 53. The carrier C is, for example, a front opening unified pod (FOUP).
The gate valves 61 to 68 are configured to be openable/closable. In addition, the opening/closing of the gate valves 61 to 68 are controlled by the controller 70.
The controller 70 controls the entire substrate processing system 1 by performing, for example, the operations of the processing chambers 11 to 14, the operations of the transfer mechanisms 21 and 41, the opening/closing of the gate valves 61 to 68, and the switching between the vacuum (depressurized) atmosphere and the air atmosphere in the load-lock chambers 31 and 32.
Next, examples of operations of the substrate processing system will be described. For example, the controller 70 opens the gate valve 67 and controls the transfer mechanism 41 to transfer, for example, a substrate W accommodated in the carrier C in the load port 51 to the stage 31a of the load-lock chamber 31. The controller 70 closes the gate valve 67 and creates a vacuum (depressurized) atmosphere in the load-lock chamber 31.
The controller 70 opens the gate valves 61 and 65, and controls the transfer mechanism 21 to transfer the substrate W in the load-lock chamber 31 to the stage 11a of the processing chamber 11. The controller 70 closes the gate valves 61 and 65 and operates the processing chamber 11. As a result, the processing chamber 11 executes a predetermined processing (e.g., processing executed in the first processing chamber) on the substrate W.
Subsequently, the controller 70 opens the gate valves 61 and 62, and controls the transfer mechanism 21 to transfer the substrate W processed in the processing chamber 11 to the stage 12a of the processing chamber 12. The controller 70 closes the gate valves 61 and 62 and operates the processing chamber 12. As a result, the processing chamber 12 executes predetermined processing (processing executed in the second processing chamber) on the substrate W.
The controller 70 may transfer the substrate W processed in the processing chamber 11 to the stage 13a or 14a of the processing chamber 13 or 14 capable of performing the same processing as in the processing chamber 12. The ruthenium film forming process performed in the second processing chamber takes more time than other processes. Accordingly, in an embodiment, the substrate W processed in the processing chamber 11 is transferred to one of the processing chambers 12, 13, and 14 depending on the operating states of the processing chambers 12, 13, and 14. As a result, the controller 70 may perform the ruthenium film forming process on a plurality of substrates W in parallel by using the processing chambers 12, 13, and 14. As a result, productivity can be improved.
The controller 70 controls the transfer mechanism 21 to transfer the substrates W processed in the processing chambers 12 to 14 to the stage 31a of the load-lock chamber 31 or the stage 32a of the load-lock chamber 32. The controller 70 creates an air atmosphere in the load-lock chamber 31 or the load-lock chamber 32. The controller 70 opens the gate valve 67 or the gate valve 68, and controls the transfer mechanism 41 to transfer the substrate W in the load-lock chamber 32 to, for example, the carrier C in the load port 53 so that the substrate W is accommodated in the carrier C.
As described above, with the substrate-processing system 1 illustrated in
A configuration example of the processing apparatus 400 that implements the first processing chamber in a film forming method of an embodiment will be described.
The processing apparatus 400 illustrated in
The processing apparatus 400 includes a processing container 410, a stage (placement table) 420, a shower head 430, an exhauster 440, a gas supplier 450, and a controller 460.
The processing container 410 is made of a metal such as aluminum, and has a substantially cylindrical shape. A carry-in/out port 411 is formed in the side wall of the processing container 410 for carry-in or carry-out of a substrate W. The carry-in/out port 411 is opened/closed by a gate valve 412. An annular exhaust duct 413 having a rectangular cross section is provided on the main body of the processing container 410. A slit 413a is formed along the inner peripheral surface of the exhaust duct 413. An exhaust port 413b is formed in the outer wall of the exhaust duct 413. On the top surface of the exhaust duct 413, a ceiling wall 414 is provided to close the upper opening in the processing container 410. The space between the exhaust duct 413 and the ceiling wall 414 is hermetically sealed with a seal ring 415.
The stage 420 is a member that horizontally supports a substrate W within the processing container 410, and is illustrated as a stage 11a in
A first radio-frequency power supply 444 is connected to the electrode 429 via a matcher 443. The matcher 443 matches the internal impedance of the first radio-frequency power supply 444 with a load impedance. The first radio-frequency power supply 444 applies power of a predetermined frequency to the stage 420 via the electrode 429. For example, the first radio-frequency power supply 444 applies radio-frequency power of 13.56 MHz to the stage 420 via the electrode 429. The radio-frequency power is not limited to 13.56 MHz, and, for example, 450 KHz, 2 MHz, 27 MHz, 60 MHz, 100 MHz, or the like may be appropriately used. In this way, the stage 420 also functions as a lower electrode.
The electrode 429 is connected to a power supply 449 via an ON/OFF switch 448 disposed outside the processing container 410, and also functions as an electrode that attracts a substrate W to the stage 420.
In addition, a second radio-frequency power supply 446 is connected to the shower head 430 via a matcher 445. The matcher 445 matches the internal impedance of the second radio-frequency power supply 446 with a load impedance. The second radio-frequency power supply 446 applies power of a predetermined frequency to the shower head 430. For example, the second radio-frequency power supply 446 applies radio-frequency power of 13.56 MHz to the shower head 430. The radio-frequency power is not limited to 13.56 MHz, and, for example, 450 KHz, 2 MHz, 27 MHz, 60 MHz, 100 MHz, or the like may be appropriately used. In this way, the shower head 430 also functions as an upper electrode.
The stage 420 is provided with a cover member 422 made of ceramic, such as alumina, to cover the outer peripheral region of the top surface and the side surface thereof. An adjustment mechanism 447 configured to adjust a gap G between the upper electrode and the lower electrode is provided on the bottom surface of the stage 420. The adjustment mechanism 447 includes a support member 423 and a lifting mechanism 424. The support member 423 supports the stage 420 from the center of the bottom surface of the stage 420. In addition, the support member 423 penetrates a hole formed in the bottom wall of the processing container 410 and extends to the lower side of the processing container 410, and the lower end thereof is connected to the lifting mechanism 424. The stage 420 is raised/lowered via the support member 423 by the lifting mechanism 424. The adjustment mechanism 447 raises/lowers the lifting mechanism 424 between a processing position, which is indicated by the solid line in
A flange 425 is provided on the support member 423 below the processing container 410, and a bellows 426, which partitions the atmosphere in the processing container 410 from the outside air, is provided between the bottom surface of the processing container 410 and the flange 425 to expand/contract in response to the raised/lowered movement of the stage 420.
Three lifting pins 427 (of which only two are illustrated) are provided in the vicinity of the bottom surface of the processing container 410 to protrude upward from a lifting plate 427a. The lifting pins 427 are raised and lowered via the lifting plate 427a by a lifting mechanism 428 provided below the processing container 410.
The lifting pins 427 are inserted through through-holes 420a provided in the stage 420 located at the delivery position and are configured to protrude and retract with respect to the top surface of the stage 420. The substrate W is delivered between the transfer mechanism (not illustrated) and the stage 420 by raising/lowering the lifting pins 427.
The shower head 430 supplies a processing gas into the processing container 410 in a shower form. The shower head 430 is made of a metal, is provided to face the stage 420, and has a diameter that is substantially the same as that of the stage 420. The shower head 430 includes a main body 431 fixed to the ceiling wall 414 of the processing container 410 and a shower plate 432 connected below the main body 431. A gas diffusion space 433 is formed between the main body 431 and the shower plate 432. In the gas diffusion space 433, a gas introduction hole 436 is provided through the centers of the main body 431 and the ceiling wall 414 of the processing container 410. An annular protrusion 434 protruding downward is formed on the peripheral edge of the shower plate 432. Gas ejection holes 435 are formed in the flat surface inside the annular protrusion 434. In the state in which the stage 420 is present at the processing position, the processing space 438 is formed between the stage 420 and the shower plate 432, and the top surface of the cover member 422 and the annular protrusion 434 are close to each other to form an annular gap 439 therebetween.
The exhauster 440 exhausts the interior of the processing container 410. The exhauster 440 includes an exhaust pipe 441 connected to the exhaust port 413b, and an exhaust mechanism 442 connected to the exhaust pipe 441 and including a vacuum pump, a pressure control valve, or the like. During the processing, the gas in the processing container 410 reaches the exhaust duct 413 via the slit 413a, and is exhausted from the exhaust duct 413 through the exhaust pipe 441 by the exhaust mechanism 442.
A gas supplier 450 is connected to the gas introduction hole 436 of the shower head 430 via a gas supply line 437. The gas supplier 450 supplies various gases used in the process of removing the tungsten oxide film 101 (steps S2 and S12), the process of forming the titanium film 102 (step S13), and the process of oxidizing the titanium film 102 (step S14). Various gases used in the process of removing the titanium oxide film 103 (step S21) may be supplied.
The gas supply line 437 is appropriately branched to correspond to each of the processes described above, and is provided with an opening/closing valve and a flow rate controller. The gas suppler 450 is configured to control the flow rates of various gases by controlling the opening/closing valve and the flow rate controller provided in each gas supply line.
The operation of the processing apparatus 400 configured as described above is comprehensively controlled by the controller 460. The controller 460 is, for example, a computer, and includes a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), an auxiliary memory, and the like. The CPU operates on the basis of a program stored in the ROM or the auxiliary storage device or a process condition, and controls the overall operation of the apparatus. For example, the controller 460 controls the operation of supplying various gases from the gas supplier 450, the raising/lowering operation of the lifting mechanism 424, the operation of exhausting the interior of the processing container 410 by the exhaust mechanism 442, and the power supplied from the first radio-frequency power supply 444 and the second radio-frequency power supply 446. A computer-readable program necessary for control by the controller 460 may be stored in a storage medium. The storage medium includes, for example, a flexible disk, a compact disk (CD), a CD-ROM, a hard disk, a flash memory, a DVD, or the like. In addition, the controller 460 may be provided independently of the controller 70 (see
An example of the operation of the substrate processing apparatus 400 will be described. At the start, the interior of the processing chamber 11 is in a vacuum (depressurized) atmosphere by the exhauster 440. In addition, the stage 420 is moved to the delivery position.
The controller 460 opens the gate valve 412. Here, a substrate W is placed on the lifting pins 427 by the external transfer mechanism 21 (see
The controller 460 controls the lifting mechanism 424 to move the stage 420 to the processing position. At this time, as the stage 420 is raised, the substrate W placed on the lifting pins 427 is placed on the placement surface of the stage 420.
At the processing position, the controller 460 operates the heater 421 to turn on the ON/OFF switch 448 to cause the substrate W to be attracted to the stage 420. In addition, the controller 460 also controls the gas supplier 450 to supply the gas for each process from the shower head 430 into the processing chamber 11. Thereby, the process of removing the tungsten oxide film 101 with TiCl4 gas (steps S2 and S12) is performed. In addition, the processing apparatus 400 performs the process of forming the titanium film 102 (step S13). The processing apparatus 400 also performs the process of oxidizing the titanium film 102 (step S14). In addition, the processing apparatus 400 performs the process of removing the titanium oxide film 103 (step S21). The gas after processing passes through a flow path on the top surface side of the cover member 422 and is exhausted by the exhaust mechanism 442 via the exhaust pipe 441.
In the process of removing the tungsten oxide film 101 (steps S2 and S12), the gas supplier 450 supplies TiCl4 gas and Ar gas. Radio-frequency power is not supplied from the first radio-frequency power supply 444 and the second radio-frequency power supply 446 (no plasma is generated). The heater 421 controls the temperature of the stage 420 (the substrate) to 300 degrees C. to 600 degrees C.
On the other hand, in the process of forming the titanium film 102 (step S13), the gas supplier 450 supplies TiCl4 gas, H2 gas, NH3 gas, and Ar gas. In addition, radio-frequency power is supplied from the first radio-frequency power supply 444 or from both the first radio-frequency power supply 444 and the second radio-frequency power supply 446 to generate plasma. The temperature of the stage 420 (the substrate) is continuously controlled between 300 degrees C. and 600 degrees C.
In the process of oxidizing the titanium film 102 (step S14), O2 gas is supplied from the gas supplier 450. Plasma may or may not be generated. In addition, the temperature of the stage 420 (the substrate) is continuously controlled between 300 degrees C. and 600 degrees C.
In the process of removing the titanium oxide film 103 (step S21), the gas supplier 450 supplies Cl2 gas and Ar gas. In addition, radio-frequency power is supplied from the first radio-frequency power supply 444 or from both the first radio-frequency power supply 444 and the second radio-frequency power supply 446 to generate plasma. The temperature of the stage 420 (the substrate) is controlled to 300 degrees C. to 500 degrees C.
After predetermined processing is completed, the controller 460 turns off the ON/OFF switch 448 to release the attraction of the substrate W to the stage 420, and controls the lifting mechanism 424 to move the stage 420 to the delivery position. At this time, the heads of the lifting pins 427 protrude from the placement surface of the stage 420 to raise the substrate W from the placement surface of the stage 420.
The controller 460 opens the gate valve 412. Here, the substrate W placed on the lifting pins 427 is carried out by the external transfer mechanism 21. When the transfer mechanism 21 comes out of the carry-in/out port 411, the controller 460 closes the gate valve 412.
In this way, with the processing apparatus 400 illustrated in
Next, a configuration example of a processing apparatus 500 that implements the second processing chamber in a film forming method of an embodiment will be described.
The processing apparatus 500 illustrated in
The processing apparatus 500 illustrated in
The processing apparatus 500 includes a main body container 501 and a support member 502. A main body container 501 is a bottomed container having an opening at the upper side thereof. The support member 502 supports a gas ejection mechanism 503. In addition, the support member 502 closes the upper opening of the main body container 501 to seal the main body container 501 and to form the processing chamber 13. A gas supplier 504 supplies a process gas such as a ruthenium-containing raw material gas or a carrier gas to the gas ejection mechanism 503 through a supply pipe 502a penetrating the support member 502. The ruthenium-containing raw material gas and the carrier gas supplied from the gas supplier 504 are supplied into the processing chamber 13 from the gas ejection mechanism 503.
A stage (placement table) 505 is a member on which a substrate W is placed, and is illustrated as a stage 13a in
The shaft of the temperature control jacket 508 penetrates the bottom portion of the main body container 501. The lower end portion of the temperature control jacket 508 is supported by the lifting mechanism 510 via the lifting plate 509 disposed below the main body container 501. A bellows 511 is provided between the bottom portion of the main body container 501 and the lifting plate 509, so that airtightness in the main body container 501 is also maintained by the vertical movement of the lifting plate 509.
When the lifting mechanism 510 raises/lowers the lifting plate 509, the stage 505 raised/lowered between a processing position (see
Lifting pins 512 support the substrate W from the bottom surface of the substrate W and raise the substrate W from the placement surface of the stage 505 when the substrate W is delivered between the stage 505 and the external transfer mechanism 21 (see
In the state in which the stage 505 is moved to the processing position of the substrate W (see
An annular member 514 is disposed above the stage 505. In the state in which the stage 505 is moved to the processing position (see
A chiller unit 515 circulates coolant (e.g., cooling water) through a flow path 508a formed in the plate of the temperature control jacket 508 through pipes 515a and 515b.
A heat transfer gas supplier 516 supplies a heat transfer gas (e.g., He gas) to the space between the rear surface of the substrate W placed on the stage 505 and the placement surface of the stage 505 through a pipe 516a.
The purge gas supplier 517 causes a purge gas to flow through a pipe 517a, the gap between the support 505a and the hole of the temperature control jacket 508, a flow path formed between the stage 505 and the heat insulating ring 507 and extending radially outward, and a vertical flow path formed in the outer peripheral portion of the stage 505. Then, through these flow paths, the purge gas, such as carbon monoxide (CO) gas, is supplied to the space between the bottom surface of the annular member 514 and the top surface of the stage 505. Thus, the process gas is prevented from flowing into the space between the bottom surface of the annular member 514 and the top surface of the stage 505, thereby preventing a film from being formed on the bottom surface of the annular member 514 or the top surface of the outer peripheral portion of the stage 505.
The side wall of the main body container 501 is provided with a carry-in/out port 501a for carry-in/out of a substrate W and a gate valve 518 for opening/closing the carry-in/out port 501a. The gate valve 518 is illustrated as the gate valve 63 in
An exhauster 519 including a vacuum pump or the like is connected to the lower side wall of the main body container 501 through an exhaust pipe 501b. The interior of the main body container 501 is exhausted by the exhauster 519, so that the interior of the processing chamber 13 is set to and maintained at a predetermined vacuum (depressurized) atmosphere (e.g., 1.33 Pa).
The controller 520 is, for example, a computer, and includes a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), an auxiliary memory, and the like. The CPU of the controller 520 controls the gas supplier 504, the heater 506, the lifting mechanism 510, the chiller unit 515, the heat transfer gas supplier 516, the purge gas supplier 517, the gate valve 518, the exhauster 519, and the like. As a result, the controller 520 controls the operation of the processing apparatus 500. A computer-readable program necessary for control by the controller 520 may be stored in a storage medium. The storage medium includes, for example, a flexible disk, a compact disk (CD), a CD-ROM, a hard disk, a flash memory, a DVD, or the like. In addition, the controller 520 may be provided independently of the controller 70 (see
An example of the operation of the substrate processing apparatus 500 will be described. At the start, the interior of the processing chamber 13 is in a vacuum (depressurized) atmosphere by the exhauster 519. In addition, the stage 505 is moved to the delivery position.
The controller 520 opens the gate valve 518. Here, a substrate W is placed on the lifting pins 512 by the external transfer mechanism 21. When the transfer mechanism 21 comes out of the carry-in/out port 501a, the controller 520 closes the gate valve 518.
The controller 520 controls the lifting mechanism 510 to move the stage 505 to the processing position. At this time, as the stage 505 is raised, the substrate W placed on the lifting pins 512 is placed on the placement surface of the stage 505. In addition, the annular member 514 comes into contact with the outer peripheral portion of the top surface of the substrate W, and presses the substrate W against the placement surface of the stage 505 by its own weight.
At the processing position, the controller 520 controls the gas supplier 504 to supply various gases in the process of forming the ruthenium film 130 (steps S4 and S17) and the process of removing the titanium oxide film 103 (step S16). In addition, the controller 520 operates the heater 506 to control the temperature of the stage 420 (the substrate) to 100 degrees C. to 300 degrees C. in the process of forming the ruthenium film 130 (steps S4 and S17). In the process of removing the titanium oxide film 103 (step S16), the temperature of the stage 420 (the substrate) is controlled to 100 degree C. to 500 degree. As a result, predetermined processing such as formation of a ruthenium film on the substrate W is performed. The gas after the processing passes through the flow path on the top surface side of the annular member 514 and is exhausted by the exhauster 519 through the exhaust pipe 501b.
At this time, the controller 520 controls the heat transfer gas supplier 516 to supply a heat transfer gas to the space between the rear surface of the wafer W placed on the stage 505 and the placement surface of the stage 505. In addition, the controller 520 controls the purge gas supplier 517 to supply a purge gas to the space between the bottom surface of the annular member 514 and the top surface of the stage 505. The purge gas passes through the flow path on the bottom surface side of the annular member 514 and is exhausted by the exhauster 519 through the exhaust pipe 501b.
When the predetermined processing is completed, the controller 520 controls the lifting mechanism 510 to move the stage 505 to the delivery position. At this time, by lowering the stage 505, the annular member 514 is engaged with an engagement portion (not illustrated). In addition, when the lower ends of the lifting pins 512 abut on the abutment member 513, the heads of the lifting pins 512 protrude from the placement surface of the stage 505 and raise the substrate W from the placement surface of the stage 505.
The controller 520 opens the gate valve 518. Here, the substrate W placed on the lifting pins 512 is carried out by the external transfer mechanism 21. When the transfer mechanism 21 comes out of the carry-in/out port 501a, the controller 520 closes the gate valve 518.
As described above, with the processing apparatus 500 illustrated in
The film forming methods and the substrate processing systems according to the embodiments disclosed herein should be considered as being exemplary in all respects and not restrictive. The embodiments may be modified and improved in various forms without departing from the scope and spirit of the appended claims. The matters described in the plurality of embodiments described above may take other configurations within the non-contradictory range and may be combined within the non-contradictory range. For example, it is also possible to perform the process of removing a titanium oxide film in the second processing chamber immediately after the process of forming a titanium film.
The processing apparatuses of the present disclosure are applicable to any of an atomic layer deposition (ALD) type apparatus, a capacitively coupled plasma (CCP) type apparatus, an inductively coupled plasma (ICP) type apparatus, a radial line slot antenna (RLSA) type apparatus, an electron cyclotron resonance plasma (ECR) type apparatus, and a helicon wave plasma (HWP) type apparatus.
According to an aspect, a tungsten oxide film can be effectively removed before embedding a ruthenium film in a recess.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosures. Indeed, the embodiments described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the disclosures. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosures.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-155501 | Sep 2022 | JP | national |
| 2023-035971 | Mar 2023 | JP | national |
