JP5632946B2 - Shielding member - Google Patents

Description

  The present invention relates to a shielding member used in a vacuum container when manufacturing a semiconductor device.

  A sputtering method for depositing a thin film on a substrate uses a vacuum container evacuated to a vacuum, and a target holder that holds a deposition source called a target made of a material to be deposited on the substrate in the vacuum container, and the substrate is placed. A substrate holder with a surface to be cut is installed, and an inert gas such as Ar, an inert gas such as nitrogen, or a process gas composed of a mixed gas thereof is introduced into the vacuum vessel, and a high voltage is applied to the target. This is a deposition method in which a target material is attached to a substrate supported by a substrate holder by utilizing the sputtering phenomenon of the target by charged particles in the discharge plasma by generating plasma.

  When positive ions in the plasma enter a target material having a negative potential, atoms and molecules of the target material are blown off from the target material. This is called sputtered particles. The sputtered particles adhere to the substrate to form a film containing the target material. In a sputtering apparatus, an openable / closable shielding plate called a shutter is usually provided between a target material and a substrate.

  The shutter is mainly used for three purposes. The first purpose is to perform pre-sputtering. In a normal sputtering apparatus, plasma is not generated simultaneously with the application of a high voltage, but is generated with a delay time of about 0.1 seconds from the voltage application. Alternatively, plasma is not generated even when a voltage is applied, or even if generated, a phenomenon such as plasma being unstable immediately after the start of discharge occurs. Due to these phenomena, there arises a problem that a film cannot be formed with a stable film thickness and film quality. In order to avoid this problem, the shutter is started to perform so-called pre-sputtering, in which the discharge is started with the shutter closed and the shutter is opened after the discharge is stabilized so that the sputter particles are deposited on the substrate. Is used.

  The second purpose is to perform conditioning. Conditioning is not the purpose of depositing sputtered particles on the substrate, but a discharge performed to stabilize the characteristics of the deposited film.

  For example, before the start of continuous film formation for production, discharge under the same conditions as the continuous film formation conditions is performed in order to stabilize the atmosphere inside the vacuum vessel. In particular, in the case of a reactive sputtering method in which the gas to be introduced is a reactive gas such as nitrogen or oxygen, or a mixed gas of a reactive gas and Ar, and an oxide or nitride of a target material is deposited, the deposition is stable. In addition, it is important to keep the inner surface of the vacuum container in the same state as when the film is formed by continuous film formation. The reason for this is that when a reactive gas is introduced into the vacuum vessel while the inner surface of the vacuum vessel is covered with a film made of a target material, a bonding reaction between the film and the reactive gas occurs, so the atmosphere inside the vacuum vessel This is because the film characteristics are not stable, and thus the film characteristics are not stable.

  However, the sputtered particles adhere not only to the inner surface of the vacuum vessel but also to the substrate placement surface of the substrate holder. To prevent this, the substrate mounting surface of the substrate holder is hidden from the sputtering surface of the target, and the shutter is provided near the substrate holder so that the inner surface of the vacuum vessel is not hidden. An inert gas and a reactive gas are introduced into the vacuum vessel to prevent discharge while preventing film formation. Thereby, nitrides and oxides adhere to the inner surface of the vacuum vessel. By sufficiently depositing nitride or oxide on the inner surface of the vacuum container in advance and starting deposition on the substrate, the film quality of the thin film deposited on the substrate can be stabilized.

  Conditioning may also discharge under conditions different from the production conditions during the continuous film formation for production. For example, when a highly stressed film is continuously deposited on the substrate by the reactive sputtering method, the film attached to the inside of the vacuum vessel is peeled off by the stress. The peeled film adheres to the substrate and deteriorates the characteristics of the electronic device. In order to prevent this, a metal film having a small stress may be periodically formed by a non-reactive sputtering method. For example, when TiN is continuously formed, the Ti film is periodically conditioned. If only TiN film is continuously formed, the TiN film attached to the deposition shield or the like inside the vacuum vessel is peeled off, but this can be prevented by conditioning Ti film formation periodically.

  The third purpose is to perform target cleaning. Target cleaning is performed using a shutter when a contaminated or oxidized target surface is previously sputtered to remove a contaminated or oxidized portion of the target before continuous film formation for production. When the target is manufactured, the target is formed by machining with a lathe or the like in the final process. At this time, contaminants generated from the grinding tool adhere to the target surface, or the target surface is moved during the transportation of the target. It will oxidize. Before the film formation, it is necessary to sufficiently sputter the target surface to expose the clean target surface. In such a case, sputtering is performed with the shutter closed so that contaminated or oxidized target particles do not adhere to the substrate mounting surface of the substrate holder.

  By the way, with the recent demand for higher performance of devices, in the semiconductor device manufacturing process, the target material adhering to the back surface of the semiconductor substrate is diffused into the semiconductor substrate by the heat treatment process, or the device characteristics are deteriorated. There have been problems such as contamination of substrate processing apparatuses in subsequent processes after being brought in after the process. Here, the contamination of other devices using the back surface of the substrate as a medium has a large effect even if the amount of the target material attached to the back surface of the substrate is very small, for example, about 1 × 10 11 atoms / cm 2, so strict management is required. ing.

  The above problem occurs because a very small amount of sputtered particles pass through the gap because there is a gap around the shutter even when the shutter is closed. That is, sputtered particles adhere to the substrate installation surface of the substrate holder during conditioning and target cleaning, which not only adheres to the back surface of the substrate and contaminates the substrate, but is transported to the next process, so other manufacturing equipment This is due to contamination.

  As a technique for avoiding the problem of sputtered particle wrapping at the time of target cleaning or pre-sputtering, for example, in Patent Document 1, a cylindrical cathode cover is installed around the target, and the shutter is connected to the end of the cathode cover. And a technique provided with a minimum gap is disclosed.

  Patent Documents 2 and 3 disclose apparatuses having two shutters between a substrate and a target or between a substrate and a vapor deposition source.

JP-A-8-269705 JP 2002-302763 A JP-A-8-78791

  However, in the apparatus in Patent Document 1, no specific shape is disclosed for the gap between the shutter and the cathode cover opening. On the other hand, as described above, there is a need to eliminate film adhesion on the substrate installation surface at the atomic number level as the performance of electronic devices increases, but in the structure in which a gap is provided between the shutter and the cathode cover opening surface, the atomic level is low. Spattering of sputtered particles could not be prevented.

  In Patent Documents 2 and 3, there is an advantage that film formation can be started in a stable state and generation of particles can be suppressed. However, it did not solve the problem of spattering particles.

  In view of the above-mentioned problems of the prior art, the present invention provides a method for producing a semiconductor device, wherein when sputtering is performed for conditioning and target cleaning in an apparatus for depositing a thin film on a substrate by sputtering, the sputtered particles are contained in a vacuum vessel. Is a shielding member that prevents the substrate holder from adhering to the substrate mounting surface of the substrate holder, and thus suppresses substrate contamination and contamination of other manufacturing equipment. It aims at providing the shielding member which suppressed generating.

  A shielding member according to the present invention is a shielding member used in a vacuum container including a target holder for holding a target and a substrate holder connected to a rotation mechanism for placing a substrate, To be in a closed state in which the space between the substrate holder and the target holder is closed by the first driving means, or an open state in which the space between the substrate holder and the target holder is opened by the first driving means. And at least one ring shape extending in the direction of the second member. The second member is disposed on the surface of the substrate holder and on the outer periphery of the substrate. A concentric first protrusion having the first member is formed on the first member, and the substrate holder is in contact with the first protrusion at a position close to the first member. Interdigitated with said second projecting portion concentric with at least one ring-shaped extending in the first member direction, characterized in that it is formed in the second member.

  According to the present invention, during the manufacture of an electronic device, when discharge for the purpose of conditioning and target cleaning is performed in an apparatus for depositing a thin film on a substrate by a sputtering method, sputtered particles are contained in a substrate holder provided in a vacuum vessel. It is possible to provide a shielding member that prevents the substrate from adhering to the substrate mounting surface and prevents substrate contamination and contamination of other manufacturing apparatuses.

  Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same or similar components are denoted by the same reference numerals.

The accompanying drawings are included in the specification, constitute a part thereof, show an embodiment of the present invention, and are used to explain the principle of the present invention together with the description.
It is the schematic of the film-forming apparatus concerning embodiment of this invention. It is a block diagram of the main control part for operating the film-forming apparatus shown in FIG. 1A. FIG. 3 is a diagram showing an outline of a substrate shutter 19 facing the substrate peripheral cover ring 21. FIG. 3 is a diagram showing an outline of a substrate peripheral cover ring 21 facing a substrate shutter 19. It is a figure explaining the positional relationship of the board | substrate shutter 19 and the board | substrate periphery cover ring 21. FIG. It is a figure explaining the positional relationship of the board | substrate shutter 19 and the board | substrate periphery cover ring 21. FIG. It is a figure explaining the positional relationship of the board | substrate shutter 19 and the board | substrate periphery cover ring 21. FIG. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining the operation | movement procedure of the film-forming apparatus in conditioning. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining operation | movement of the film-forming apparatus in the case of performing pre-sputtering operation | movement and film-forming on a board | substrate. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is a figure explaining the modification of the labyrinth seal formed of the board | substrate shutter 19 and the board | substrate periphery cover ring. It is the schematic which shows the modification of the film-forming apparatus concerning embodiment of this invention. It is a figure which shows schematic structure of the laminated film forming apparatus for flash memories which is an example of the vacuum thin film forming apparatus provided with the film-forming apparatus concerning embodiment of this invention. It is a figure which illustrates the flow which processes an electronic device product using the film-forming apparatus concerning embodiment of this invention. It is a figure which shows the procedure at the time of performing conditioning using the film-forming apparatus concerning embodiment of this invention. It is a figure explaining the starting condition of conditioning. It is a figure which shows the result of having measured the number of particles adhering on a board | substrate once a day when the process of FIG. 10 was implemented using the film-forming apparatus concerning embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  With reference to FIG. 1A, FIG. 1B, FIG. 2, and FIG. 3, the whole structure of the sputtering apparatus of this invention (henceforth "the film-forming apparatus") is demonstrated. FIG. 1A is a schematic diagram of a film forming apparatus 1 according to an embodiment of the present invention. The film forming apparatus 1 introduces an inert gas into the vacuum container 2, a vacuum exhaust apparatus having a vacuum container 2, a turbo molecular pump 48 that exhausts the inside of the vacuum container 2 through the exhaust port 8, and a dry pump 49. An inert gas introduction system 15 capable of introducing a reactive gas, and a reactive gas introduction system 17 capable of introducing a reactive gas.

  The exhaust port 8 is a conduit having a rectangular cross section, for example, and connects the vacuum vessel 2 and the turbo molecular pump 48. A main valve 47 is provided between the exhaust port 8 and the turbo molecular pump 48 to shut off the film forming apparatus 1 and the turbo molecular pump 48 when maintenance is performed.

  An inert gas supply device (gas cylinder) 16 for supplying an inert gas is connected to the inert gas introduction system 15. The inert gas introduction system 15 includes piping for introducing an inert gas, a mass flow controller for controlling the flow rate of the inert gas, valves for shutting off and starting the gas supply, and A pressure reducing valve, a filter, and the like are configured as necessary, and a gas flow rate designated by a control device (not shown) can be stably flowed. The inert gas is supplied from the inert gas supply device 16 and the flow rate of the inert gas is controlled by the inert gas introduction system 15 and then introduced into the vicinity of the target 4 described later.

  A reactive gas supply device 18 for supplying a reactive gas is connected to the reactive gas introduction system 17. The reactive gas introduction system 17 includes piping for introducing reactive gas, a mass flow controller for controlling the flow rate of the inert gas, valves for shutting off and starting the gas flow, and A pressure reducing valve, a filter, and the like are configured as necessary, and a gas flow rate designated by a control device (not shown) can be flowed stably.

  The reactive gas is supplied from the reactive gas supply device 18 and the flow rate of the reactive gas is controlled by the reactive gas introduction system 17, and then the reactive gas is introduced in the vicinity of a substrate holder 7 that holds a substrate 10 described later. The inert gas and the reactive gas are introduced into the vacuum vessel 2 and then sputtered particles are generated or used to form a film as will be described later. The air is exhausted by the pump 48 and the dry pump 49.

  In the vacuum vessel 2, the target 4 with the exposed surface to be sputtered is held by the back plate 5, and the substrate 10 is held at a predetermined position where the sputtered particles emitted from the target 4 reach. A substrate holder 7 is provided. The vacuum vessel 2 is provided with a pressure gauge 41 for measuring the pressure in the vacuum vessel 2. The inner surface of the vacuum vessel 2 is electrically grounded. A cylindrical shield 40 that is electrically grounded is provided on the inner surface of the vacuum vessel 2 between the target holder 6 and the substrate holder 7. The shield 40 prevents the sputtered particles from directly adhering to the inner surface of the vacuum vessel 2 and has a replaceable structure.

  A magnet 13 for realizing magnetron sputtering is disposed behind the target 4 as viewed from the sputtering surface. The magnet 13 is held by the magnet holder 3 and can be rotated by a magnet holder rotation mechanism (not shown). In order to make the erosion of the target uniform, the magnet holder 3 rotates during discharge.

  The target 4 is installed at a position (offset position) disposed obliquely above the substrate 10. That is, the center point of the sputtering surface of the target 4 is at a position that is shifted by a predetermined dimension with respect to the normal line of the center point of the substrate 10. The target holder 6 is connected to a power supply 12 for applying sputtering discharge power. The film forming apparatus 1 shown in FIG. 1A includes a DC power source, but is not limited thereto, and may include, for example, an RF power source. When the RF power source is used, a matching unit is installed between the power source 12 and the target holder 6.

  The target holder 6 is insulated from the vacuum vessel 2 by an insulator 34, and is made of a metal such as Cu, so that it becomes an electrode when DC or RF power is applied. The target holder 6 has a water channel (not shown) inside, and is configured to be cooled by cooling water supplied from a water pipe (not shown). The target 4 is composed of material components that are desired to be deposited on the substrate. Since it relates to the purity of the film, a high purity is desirable. The back plate 5 installed between the target 4 and the target holder 6 is made of a metal such as Cu and holds the target 4. Alternatively, the target 4 may be directly fixed to the target holder 6 without using the back plate 5. In this case, there is a problem that the shape of the target is complicated. On the other hand, there is no need to bond the back plate and the target.

  A target shutter 14 is installed near the target holder 6 so as to cover the target holder 6. The target shutter 14 is a shielding member (third shielding member) for closing the space between the substrate holder 7 and the target holder 6 or opening the space between the substrate holder 7 and the target holder 6. Function as. The target shutter 14 is provided with a target shutter drive mechanism 33.

  A second shielding member having a ring shape (hereinafter also referred to as “substrate peripheral cover ring 21”) is provided on the substrate installation surface side of the substrate holder 7 and on the outer edge side (outer peripheral portion) of the substrate 10. . The substrate peripheral cover ring 21 prevents the sputtered particles from adhering to a place other than the film formation surface of the substrate 10. Here, the place other than the film formation surface includes the side surface and the back surface of the substrate 10 in addition to the portion of the substrate holder 7 covered by the substrate peripheral cover ring 21. The substrate holder 7 is provided with a substrate holder drive mechanism 31 for moving the substrate holder 7 up and down or rotating at a predetermined speed. The substrate holder drive mechanism 31 raises the substrate holder 7 toward the closed substrate shutter 19 (first shielding member) or lowers the substrate holder 19 with respect to the substrate shutter 19 (first shielding member). The substrate holder 7 can be moved up and down.

  A substrate shutter 19 is disposed between the substrate holder 7 and the target holder 6 in the vicinity of the substrate 10. The substrate shutter 19 is supported by the substrate shutter support member 20 so as to cover the surface of the substrate 10. The substrate shutter drive mechanism 32 rotates the substrate shutter support member 20 to insert the substrate shutter 19 between the target 4 and the substrate 10 (closed state). At this time, the space between the target 4 and the substrate 10 is shielded. Similarly, when the substrate shutter 19 is retracted from between the target holder 6 (target 4) and the substrate holder 7 (substrate 10) by the operation of the substrate shutter drive mechanism 32, the target holder 6 (target 4) and the substrate holder 7 ( The substrate 10) is opened (open state). As described above, the substrate shutter drive mechanism 32 is configured so as to close the substrate shutter 7 and the target holder 6 or to open the space between the substrate holder 7 and the target holder 6. 19 is opened and closed.

  The substrate shutter 19 is configured to be retractable into the exhaust port 8. As shown in FIG. 1A, it is preferable that the retreat location of the substrate shutter 19 is accommodated in the conduit of the exhaust path to the turbo molecular pump 48 for high vacuum exhaust, because the device area of the device can be reduced.

  The substrate shutter 19 is made of stainless steel or aluminum alloy. Moreover, when heat resistance is calculated | required, it may be comprised with titanium or a titanium alloy. The surface of the substrate shutter 19 is blasted by sandblasting or the like, and minute irregularities are provided on the surface. Therefore, the film attached to the substrate shutter 19 becomes difficult to peel off, and particles generated by the peeling can be reduced. In addition to blasting, a metal thin film may be formed on the surface of the substrate shutter 19 by metal spraying or the like. In this case, the thermal spraying process is more expensive than blasting alone. However, when removing the substrate shutter 19 and removing the adhered film, it is only necessary to dissolve the sputtered film together with the sprayed film with a chemical solution, etc. There is an advantage of not giving. In addition, since the flexible Al film enhances the adhesion between the sputtered film and the sputtered film, it has an effect of preventing the sputtered film from being peeled off by its own stress.

  Next, the shapes of the substrate peripheral cover ring 21 and the substrate shutter 19 will be described with reference to FIGS. FIG. 3 is a diagram showing an outline of the substrate peripheral cover ring 21 facing the substrate shutter 19. The substrate peripheral cover ring 21 is formed with a protrusion having a ring shape extending in the direction of the substrate shutter 19. As described above, the substrate peripheral cover ring 21 has a ring shape, and concentric protrusions (protrusions 21 a and 21 b) are provided on the surface of the substrate peripheral cover ring 21 that faces the substrate shutter 19.

  FIG. 2 is a diagram showing an outline of the substrate shutter 19 facing the substrate peripheral cover ring 21. The substrate shutter 19 is formed with a protrusion having a ring shape extending in the direction of the substrate peripheral cover ring 21. A protrusion (protrusion 19 a) is provided on the surface of the substrate shutter 19 facing the substrate peripheral cover ring 21. Note that the circumference of the protrusion 21a, the protrusion 19a, and the protrusion 21b is formed larger in this order.

  At the position where the substrate holder is raised by the substrate holder driving mechanism 31, the protrusion 19a and the protrusions 21a and 21b are fitted in a non-contact state. Alternatively, at the position where the substrate shutter 19 is lowered by the substrate shutter driving mechanism 32, the protrusion 19a and the protrusions 21a and 21b are fitted in a non-contact state. In this case, the other protrusion 19a fits in the recess formed by the plurality of protrusions 21a and 21b in a non-contact state.

  FIG. 1B is a block diagram of the main control unit 100 for operating the film forming apparatus 1 shown in FIG. 1A. The main control unit 100 includes a power supply 12 for applying sputtering discharge power, an inert gas introduction system 15, a reactive gas introduction system 17, a substrate holder drive mechanism 31, a substrate shutter drive mechanism 32, a target shutter drive mechanism 33, and a pressure gauge 41. , And a gate valve, respectively, and configured to manage and control the operation of a film forming apparatus to be described later.

  Note that the storage device 63 provided in the main control unit 100 stores a control program for executing the conditioning according to the present invention, a film forming method on a substrate accompanied by pre-sputtering, and the like. For example, the control program is implemented as a mask ROM. Alternatively, the control program can be installed in a storage device 63 configured by a hard disk drive (HDD) or the like via an external recording medium or a network.

  Next, the positional relationship between the substrate shutter 19 and the substrate peripheral cover ring 21 will be described with reference to FIGS. 4A to 4C. In FIG. 4A, the substrate shutter 19 and the substrate peripheral cover ring 21 are close to each other and the protrusions on the opposite surfaces are combined to form a labyrinth seal (hereinafter referred to as “position A”). Is shown. The labyrinth seal referred to here is a kind of non-contact seal, in which the respective protrusions (the recesses formed by 21a and 21b and the protrusions formed by 19a) formed on the opposing surfaces are fitted. It is in a non-contact state, that is, a certain gap is formed between the concave and convex portions. Since the sputtered particles ejected from the target have a property of traveling straight in the sputter chamber, they cannot pass through the gap between the convex portion and the concave portion. Therefore, it is possible to prevent the sputtered particles from adhering to the surface of the substrate holder 7 or the like.

  4A, in the state where the labyrinth seal is formed (position A), the height of the protrusion with respect to the flat surface of the substrate shutter 19 is H1, the height of the protrusion with respect to the flat surface of the substrate peripheral cover ring 21 is H2, and the substrate shutter The distance between the flat surfaces of 19 and the substrate peripheral cover ring 21 is D1. At this time, in a state where the labyrinth seal is formed (position A), the relationship of D1 <H1 + H2 is satisfied.

  In the state where the labyrinth seal at position A is formed, the projection 19a of the substrate shutter 19 and the three projections of the substrate peripheral cover rings 21a and 21b are fitted to each other. As will be described later, since the conditioning process is performed in this state, it is possible to prevent sputter particles from adhering to the surface of the substrate holder 7.

  FIG. 4B shows a state (hereinafter referred to as “position B”) in which the minimum distance at which the substrate shutter 19 and the substrate peripheral cover ring 21 do not contact each other is maintained when the substrate shutter 19 is opened and closed. At the position B, the relationship of D1> H1 + H2 is satisfied.

  FIG. 4C shows a state where the distance between the substrate shutter 19 and the substrate holder 7 is maximized (hereinafter referred to as “position C”). At this time, the substrate can be transported to the substrate placement surface of the substrate holder 7 from the gap formed between the substrate shutter 19 in the state C and the substrate peripheral cover ring 21. In this embodiment, the position of the substrate peripheral cover ring 21 is moved by moving the substrate holder 7 up and down to adjust the distance between the substrate shutter 19 and the substrate peripheral cover ring 21. However, the present embodiment is limited to this example. For example, the substrate shutter drive mechanism 32 may be configured to move the substrate shutter 19 up and down. That is, the substrate shutter drive mechanism 32 lowers the closed substrate shutter 19 (first shielding member) toward the substrate holder 7 on which the substrate peripheral covering 21 (second shielding member) is installed, or In order to raise the substrate holder 7, the substrate shutter 19 (first shielding member) can be moved up and down.

  Alternatively, the substrate shutter drive mechanism 32 and the substrate holder drive mechanism 31 can move the substrate shutter 19 and the substrate holder 7 in the up and down directions to the position C.

  In the present embodiment, the substrate shutter support member 20 opens and closes the substrate shutter 19 by a rotating operation. However, if the space between the target 4 and the substrate 10 can be opened and closed, for example, a horizontal introduction mechanism or the like can be used. It is also possible to slide the substrate shutter 19 in the direction.

(Operation during conditioning)
Next, the operation of the film forming apparatus 1 during conditioning will be described with reference to FIGS. 5A to 5F. In this case, the conditioning treatment means that discharge is performed to stabilize the film formation characteristics with the substrate shutter 19 closed so that the film formation on the substrate is not affected, and the sputtered particles adhere to the inner wall of the chamber. This is the processing to be performed.

  First, the main control unit 100 instructs the substrate shutter drive mechanism 32 to close the substrate shutter 19. Next, the main control unit 100 instructs the target shutter drive mechanism 33 to close the target shutter 14. In response to an instruction from the main control unit 100, the target shutter 14 and the substrate shutter 19 are closed. In this state, the substrate holder 7 is placed at a position C which is a standby position.

  Subsequently, the main control unit 100 instructs the substrate holder drive mechanism 31 to perform the ascending operation, so that the substrate holder 7 is positioned at the position where the labyrinth seal is formed from the position C (FIG. 4C) which is the standby position (FIG. 4C). It moves upward to position A (FIG. 4A)) (FIG. 5A).

  Next, as shown in FIG. 5B, the main control unit 100 closes the target shutter 14 with the inert gas (Ne, Kr, Xe in addition to Ar) from the inert gas introduction system 15 near the target. A control device that controls the inert gas introduction system 15 is instructed to introduce it. At this time, as shown in FIG. 5B, by introducing an inert gas in the vicinity of the target, the pressure in the vicinity of the target becomes higher than that in the vicinity of the substrate, so that discharge is easily performed. In this state, electric power is applied from the power source 12 to the target to start discharging. At this time, since a labyrinth seal is formed between the substrate shutter 19 and the substrate peripheral cover ring 21, it is possible to prevent sputter particles from adhering to the substrate mounting surface of the substrate holder 7.

  Next, as shown in FIG. 5C, the main control unit 100 instructs the target shutter drive mechanism 33 to be driven and the target shutter 14 to be opened. Thereby, the conditioning to the inner wall of the chamber is started. The sputtered particles that have jumped out of the target 4 adhere to the inner wall of the chamber and deposit a film. When the shield 40 is provided on the inner wall, sputtered particles adhere to the surface of the shield 40 and a film is deposited. However, since a labyrinth seal is formed between the substrate shutter 19 and the substrate peripheral cover ring 21, it is possible to prevent sputter particles from entering the substrate placement surface of the substrate holder 7. In this state, conditioning is performed by forming a film on the inner wall of the chamber or a constituent member such as a shield. By performing the conditioning in this manner, the reaction between the sputtered particles and the reactive gas when the target shutter is opened can be stabilized. When conditioning by reactive sputter discharge is desired, reactive gas is introduced from the reactive gas introduction system 17 to the vicinity of the substrate at this time.

  After discharging for a predetermined time, the main control unit 100 stops the discharge by stopping the application of power to the power supply 12 (FIG. 5D). At this time, the deposited film 51 is deposited on the shield 40, the target shutter 14, the substrate shutter 19, and other surfaces facing the target.

  Next, as shown in FIG. 5E, the main control unit 100 instructs the control device that controls the inert gas introduction system 15 to stop the supply of the inert gas. The main control unit 100 instructs the reactive gas introduction system 17 to stop the supply of the reactive gas when the reactive gas is being supplied. Thereafter, the main control unit 100 instructs the target shutter drive mechanism 33 to close the target shutter 14.

  As shown in FIG. 5F, the main control unit 100 instructs the substrate holder drive mechanism 31 to move the substrate holder 7 from the position A to the position C, and the conditioning is completed.

  By the above procedure, it is possible to perform conditioning by preventing the sputter particles from entering the substrate placement surface of the substrate holder 7.

  Note that the operation at the time of target cleaning for removing impurities and oxides attached to the target before film formation can be realized by the same procedure as the operation at the time of conditioning described above.

(Pre-sputtering operation and film formation on the substrate)
Next, with reference to FIGS. 6A to 6I, the operation of the film forming apparatus 1 when performing the pre-sputtering operation and the film formation on the substrate will be described. Here, pre-sputtering refers to sputtering performed to stabilize the discharge with the shutter closed so as not to affect film formation on the substrate. Perform pre-sputtering.

  First, the main control unit 100 instructs the substrate shutter drive mechanism 32 to close the substrate shutter 19 (set to the position A state). Next, the main control unit 100 instructs the target shutter drive mechanism 33 to close the target shutter 14. As a result, the target shutter 14 and the substrate shutter 19 are closed (FIG. 6A). In this state, the substrate holder 7 is placed at a position C which is a standby position.

  Next, as shown in FIG. 6B, the main control unit 100 opens the gate valve 42 on the chamber wall, and carries the substrate 10 from the gate valve 42 by substrate transfer means (not shown) outside the chamber. Instruct. Then, the substrate 10 is carried in between the substrate shutter 19 and the substrate peripheral cover ring 21, and the substrate placement of the substrate holder 7 is performed in cooperation with the substrate transfer means outside the chamber and the lift mechanism (not shown) in the substrate holder. The substrate 10 is placed on the surface.

  As shown in FIG. 6C, the main controller 100 closes the gate valve 42 and moves the substrate holder 7 from the position C (FIG. 4C) to the position B (FIG. 4B) by the substrate holder driving mechanism 31. The position B is preferably a point where the positional relationship between the target 4 and the substrate 10 is optimal from the viewpoint of film formation distribution and the like.

  Subsequently, the main control unit 100 rotates the substrate holder 7 by driving the substrate holder driving mechanism 31 as shown in FIG. 6D. An inert gas (Ne, Kr, Xe in addition to Ar) is introduced from an inert gas introduction system 15 provided near the target. The main control unit 100 starts discharging by applying power from the power source 12 to the target. Thus, by starting sputtering with the substrate shutter 19 closed, it is possible to prevent sputtered particles from adhering to the substrate.

  After a discharge stabilization time of a predetermined time (3 to 15 seconds) for stabilizing the discharge, the main control unit 100 opens the target shutter 14 and starts pre-sputtering as shown in FIG. 6E. If an abnormality such as the discharge not starting occurs at this time, the main control unit 100 can detect the abnormality by monitoring the discharge voltage current and stop the film forming sequence. When there is no problem, the target shutter 14 is opened as described above, so that the sputtered particles adhere to the inner wall of the shield and deposit a film. In addition, when performing deposition by reactive sputtering, a reactive gas is introduced from the reactive gas introduction system 17. Sputtered particles adhere to the shield surface of the inner wall shield 40 to deposit a film.

  A labyrinth seal is not formed at position B of the substrate holder during pre-sputtering. However, since the operation of retracting the substrate holder is not necessary when the subsequent opening operation of the substrate shutter 19 is performed, the opening operation of the shutter can be performed quickly. In addition, since the substrate 10 is already placed on the substrate placement surface of the substrate holder 7, the sputter particles that slightly go around do not cause a problem in many cases. However, in order to secure the characteristics of the semiconductor element, if sputter particles that slightly go around become a problem, setting the substrate shutter 19 to position A during pre-sputtering prevents spatter of sputter particles during pre-sputtering, Further, a high quality film can be formed.

  After performing the pre-sputtering for a necessary time, the main control unit 100 opens the substrate shutter 19 by the substrate shutter drive mechanism 32 and starts film formation on the substrate 10 as shown in FIG. 6F.

  After discharging for a predetermined time, as shown in FIG. 6G, the main control unit 100 stops the discharge and stops the supply of the inert gas by stopping the application of power. Further, the main control unit 100 stops the supply of the reactive gas when the reactive gas is being supplied. The main control unit 100 closes the substrate shutter 19 and the target shutter 14. As shown in FIG. 6H, the main control unit 100 moves the substrate holder 7 from the position B to the position C.

  As shown in FIG. 6I, the gate valve 42 of the chamber is opened, the substrate is unloaded in the reverse order to the loading time, and the pre-sputtering and the film forming process on the substrate are completed.

  By operating the shutter mechanism according to the above procedure, it is possible to prevent the sputter particles from entering the substrate and form a high-quality film.

  According to the sputtering apparatus according to the present embodiment, a sputtering apparatus is provided that prevents sputtered particles from adhering to the substrate mounting surface of the substrate holder when performing discharge for conditioning, pre-sputtering, and target cleaning. Is possible.

(Modification 1)
A modified example of the labyrinth seal formed by the substrate shutter 19 and the substrate peripheral cover ring 21 will be described with reference to FIGS. 7A to 7G.

  FIG. 7A is an enlarged schematic view of the labyrinth seal formed by the substrate shutter 19 and the substrate peripheral cover ring 21 in the apparatus shown in FIG. 1A. Thus, the labyrinth seal can be formed between the substrate peripheral cover ring 21 and the substrate shutter 19 by the substrate shutter protrusion 19a provided opposite to the position between the substrate peripheral cover ring protrusions 21a and 21b. it can. When the substrate peripheral cover ring 21 has two protrusions (21a, 21b), the bending of the seal space formed in the labyrinth shutter between the protrusion 19a of the substrate shutter 19 and the protrusions 21a, 21b is a broken line region 71. It becomes four places shown by -74.

  The vertical spacing of the labyrinth seal (for example, D2 in FIG. 7A) can be changed by controlling the vertical movement of the substrate holder 7. In this case, the main controller 100 controls the vertical movement of the substrate holder 7 so that the substrate peripheral cover ring 21 and the substrate shutter 19 do not contact each other. When the substrate peripheral cover ring 21 and the substrate shutter 19 come into contact with each other, spatter particles do not wrap around the substrate mounting location of the substrate holder 7, but particles are generated at the contact portion between the substrate peripheral cover ring 21 and the substrate shutter 19. It is not preferable. This is because the particles deteriorate the film quality of film formation on the processing substrate that is subsequently transported and processed, thereby deteriorating the device yield and characteristics.

  When the substrate shutter 19 is opened and closed, the main control unit 100 operates the substrate holder driving mechanism 31 so that the protrusions (21a, 21b) of the substrate peripheral cover ring 21 do not contact the protrusions (19a) of the substrate shutter 19. The substrate holder 7 is lowered to a position (position B or position C). The control performed by the main control unit 100 so that the protrusions of the substrate shutter 19 and the protrusions of the substrate peripheral cover ring 21 do not collide (contact) is the same in the modified labyrinth seal described below.

  The labyrinth seal is formed by a combination of protrusions and protrusions or grooves provided on the substrate shutter 19 and the substrate peripheral cover ring 21. At least one of the substrate shutter 19 and the substrate peripheral cover ring 21 needs to be movable up and down. In the present embodiment, the position of the substrate peripheral cover ring 21 can be moved in the vertical direction by driving the substrate holder 7 in the vertical direction.

  The number of protrusions of the substrate shutter 19 and the substrate peripheral cover ring 21 needs to be one or more. Preferably, the number of either projection is two or more from the viewpoint of preventing the sputtered particles from entering. FIG. 7A corresponding to FIG. 1A illustrates a case where there is one protrusion of the substrate shutter 19 and two protrusions of the substrate peripheral cover ring 21.

  FIG. 7B illustrates a case where there is one protrusion on each of the substrate shutter 19 and the substrate peripheral cover ring 21. When the substrate peripheral cover ring 21 has one protrusion (21a), the bending of the seal space formed in the labyrinth shutter between the protrusion 19a of the substrate shutter 19 and the protrusion 21a is indicated by broken line areas 75 and 76. It will be two places.

  FIG. 7C illustrates a case where the substrate shutter 19 has two protrusions (19a, 19b) and the substrate peripheral cover ring 21 has one protrusion (21a). FIG. 7D illustrates a case where the substrate shutter 19 has two protrusions (19a, 19b) and the substrate peripheral cover ring 21 has two protrusions (21a, 21b).

  When there are a plurality of protrusions, for example, the heights of the protrusions may be different as shown in FIG. 7E. As long as the substrate shutter 19 and the substrate peripheral cover ring 21 do not contact each other, the height H1 or H2 of the protrusion may be longer than the distance D1 of the flat surface between the substrate shutter 19 and the substrate peripheral cover ring 21. FIG. 7E is an example in which H1 is larger than the distance D1.

  7E shows an example in which the projections provided on the substrate shutter 19 have different heights. However, the present invention is not limited to this example, and the substrate peripheral cover ring 21 may have a different projection height. Is possible.

  Further, the corners and bases of the protrusions of the substrate shutter 19 and the substrate peripheral cover ring 21 do not have to be at right angles, and may be round, for example, for ease of processing and maintenance.

  In addition, a groove dug in the substrate shutter 19 or the substrate peripheral cover ring 21 is provided on either the substrate shutter 19 or the substrate peripheral cover ring 21, and a protrusion is provided on the other to form a labyrinth seal relative to each other. The configuration as shown in FIG.

  Further, the substrate peripheral cover ring 21 has a function as a mask member (shadow ring) that prevents film formation on a portion other than the film formation surface of the substrate (end portion (outer peripheral portion) of the substrate) during film formation. Also good. In order to protect the end portion (outer peripheral portion) of the substrate from adhesion of sputtered particles, for example, as shown in FIG. 7G, the substrate peripheral cover ring 21 has a region overlapping with the end portion of the substrate. In order to mechanically fix the substrate, the overlap portion may be in contact with the substrate. Alternatively, when mechanical fixing is not required, the substrate peripheral cover ring 21 may be configured not to contact the substrate 10.

(Modification 2)
In the above-described embodiment, an example in which a single target is used has been described. However, a sputtering apparatus for a plurality of targets as shown in FIG. 8 may be used. In this case, it is necessary to provide a plurality of target shutters 14 for each target in order to prevent one target from being contaminated by adhesion of sputtered particles from the other target. By doing so, it is possible to operate so as to prevent contamination between targets.

  The following example illustrates a method for manufacturing an electronic device according to the present invention.

Example 1
A description will be given of a case where the present invention is applied to prevent TiN peeling from the chamber wall by periodically forming Ti on the chamber wall during TiN film formation. The apparatus uses the apparatus (FIG. 1A) described in the above embodiment. The target 4 uses Ti. The protrusions of the substrate shutter 19 and the substrate peripheral cover ring 21 are those shown in FIG. 7A. In the state of FIG. 7A used in this embodiment, the number of protrusions of the substrate shutter 19 is one, and the number of protrusions of the substrate peripheral cover ring 21 is two.

  Conditioning discharge (pre-sputtering) before TiN film formation is performed for 1200 seconds under the TiN film formation conditions described later, and then a laminated film of SiO2 (1.5 nm) / HfSiO (1.5 nm) on a 300 mm diameter Si substrate. The wafer on which was formed was transported to the deposition chamber 1 and placed on the substrate holder 7 to form a TiN film having a thickness of 7 nm.

  The TiN film formation conditions at that time are as follows.

  Ar gas 20 sccm as an inert gas (sccm: abbreviation of standard cc per minute, unit of gas flow rate supplied per minute converted to cm 3 at 0 ° C. and 1 atm, which is a standard state), and N 2 as a reactive gas Gas 20 sccm, pressure 0.04 Pa, power 700 W, time 240 seconds.

  The wafer was unloaded, and 300 films were formed in the same manner. The wafer was unloaded and the process was completed.

  Next, a conditioning process was performed. In the present embodiment, the height H1 of the projection of the substrate shutter 19 is one 10 mm, and the height H2 of the substrate peripheral cover ring 21 is two 10 mm. The height of the substrate shutter 19 and the substrate peripheral cover ring 21 is The distance D between the flat portions excluding the protrusions was 15 mm. The substrate holder 7 is arranged so as to be in the state of the position A shown in FIG. 4A described above, Ar gas is 50 sccm, pressure is 0.04 Pa, discharge is started at a power of 1000 W, the target shutter 14 is opened, and the substrate shutter 19 is opened. With the closed, a conditioning discharge was performed for 2400 seconds.

  Normally, the substrate is not placed on the substrate holder 7 during conditioning. However, for the purpose of this experiment, a 300 mm Si bare substrate was placed on the substrate placement surface of the substrate holder 7 for discharge.

  After the discharge is completed, the 300 mm Si bare substrate placed on the substrate holder 7 is taken out, and the substrate is subjected to a total reflection X-ray fluorescence spectrometer TXRF: total-reflection X-ray fluorescence (TREX630IIIx manufactured by Technos Co., Ltd.). When the portion of 26 to 34 mm from the end was analyzed, the amount of Ti detected was below the detection limit.

(Example 2)
In order to investigate the effect when the shape of the labyrinth path of the labyrinth seal is different from that in the first embodiment, the substrate peripheral cover ring 21 having a different number of protrusions as shown in FIG. The experiment was conducted. The substrate peripheral cover ring 21 (FIG. 7B) used in this example has one protrusion on the substrate shutter 19 and one protrusion on the substrate peripheral cover ring 21. When an experiment was performed under the same conditions as in Example 1, the detected amount of Ti was 2 × 10 10 atms / cm 2.

(Comparative Example 1)
For comparison, an experiment of conditioning discharge was performed under the same conditions except that the substrate peripheral cover ring 21 and the substrate shutter 19 of the substrate holder 7 had no protrusions and no labyrinth seal. At this time, the experiment was performed with the distance D between the substrate peripheral cover ring 21 and the flat portion of the substrate shutter 19 being the same as in the first and second embodiments. As a result, a Ti film of an extent that can be visually confirmed was formed on the outer periphery of the substrate. Since the formed Ti film was thick, it could not be measured by TXRF. When the film thickness was measured by observing the cross section with a TEM (Transmission Electron Microscope), the film thickness was about 5 nm. The thickness of the Ti film of 5 nm is approximately 3 × 10 16 atoms / cm 2 when calculated with a Ti density of 4.5. Therefore, it was confirmed that the number of sputtered particles traveling around the substrate mounting surface was much larger in the case of this comparative example having no labyrinth seal than in Examples 1 and 2 having the labyrinth seal.

  When Examples 1 and 2 and the comparative example are put together, the results shown in Table 1 are obtained. In addition, Ti amount (* mark) of the comparative example has shown the conversion value from a film thickness.

  In Examples 1 and 2 with the labyrinth seal, the amount of Ti was significantly smaller than in the comparative example without the labyrinth seal. Further, when there are two protrusions of the substrate peripheral cover ring 21 of the first embodiment (four seal space bends), the case of the second embodiment has only one protrusion (two seal space bends). Also, the amount of Ti detected was small. When there are two protrusions on one side, that is, when there are four bends in the space of the labyrinth seal, the wrap around the atomic number level is more remarkable than when there is only one protrusion, ie, only two bends in the space of the labyrinth seal. The effect which prevents was acquired. 7C, FIG. 7D, FIG. 7E, and FIG. 7F were confirmed in the same manner. As in Example 1, the Ti detection amount was below the detection limit. In these FIGS. 7C, 7D, 7E, and 7F, the labyrinth seal has four or more bends. That is, when the number of bends in the space of the labyrinth seal is four or more, it is estimated that the same effect as or more than that of the first embodiment can be obtained.

Example 3
FIG. 9 shows a schematic configuration of a laminated film forming apparatus for flash memory (hereinafter also simply referred to as “laminated film forming apparatus”), which is an example of a vacuum thin film forming apparatus including the film forming apparatus 1 according to the embodiment of the present invention. FIG. The laminated film forming apparatus shown in FIG. 9 includes a vacuum transfer chamber 910 having a vacuum transfer robot 912 therein. In the vacuum transfer chamber 910, a load lock chamber 911, a substrate heating chamber 913, a first PVD (sputtering) chamber 914, a second PVD (sputtering) chamber 915, and a substrate cooling chamber 917 are respectively connected via a gate valve 920. It is connected.

  Next, the operation of the laminated film forming apparatus shown in FIG. 9 will be described. First, a substrate to be processed (silicon wafer) is set in a load lock chamber 911 for carrying the substrate in and out of the vacuum transfer chamber 910 and evacuated until the pressure reaches 1 × 10 −4 Pa or less. Thereafter, using the vacuum transfer robot 912, the substrate to be processed is carried into the vacuum transfer chamber 910 in which the degree of vacuum is maintained at 1 × 10 −6 Pa or less, and further transferred to a desired vacuum processing chamber.

  In the present embodiment, the substrate to be processed is first transferred to the substrate heating chamber 913 and heated to 400 ° C., and then transferred to the first PVD (sputtering) chamber 914 to deposit an Al 2 O 3 thin film on the substrate to be processed by 15 nm. The film is formed to a thickness of. Next, the substrate to be processed is transferred to the second PVD (sputtering) chamber 915, and a TiN film is formed thereon to a thickness of 20 nm. Finally, the substrate to be processed is transferred into the substrate cooling chamber 917, and the substrate to be processed is cooled to room temperature. After all the processes are completed, the substrate to be processed is returned to the load lock chamber 911, and after introducing dry nitrogen gas to atmospheric pressure, the substrate to be processed is taken out from the load lock chamber 911.

  In the laminated film forming apparatus of this embodiment, the degree of vacuum in the vacuum processing chamber is set to 1 × 10 −6 Pa or less. In this embodiment, the magnetron sputtering method is used for forming the Al2O3 film and the TiN film.

  FIG. 10 is a diagram illustrating a processing flow of an electronic device product related to a method for manufacturing an electronic device using the film forming apparatus 1 according to the embodiment of the invention. Here, a case where Ti is used as the target 4 mounted on the film forming apparatus 1, argon is used as an inert gas, and nitrogen is used as a reactive gas will be described as an example.

  In step S1, after exchanging the target and the shield, the vacuum vessel 2 is evacuated and controlled to a predetermined pressure. When the predetermined pressure is reached, in step S2, target cleaning is started with the target shutter 14 and the substrate shutter 19 closed. Target cleaning refers to sputtering performed to remove impurities and oxides attached to the surface of the target. The target cleaning is performed by setting the height of the substrate holder so that the substrate shutter 19 and the substrate peripheral cover ring 21 form a labyrinth seal. By setting in this way, it is possible to prevent sputter particles from adhering to the substrate mounting surface of the substrate holder. Note that the target cleaning may be performed with the substrate placed on the substrate holder.

  Next, in step S <b> 3, the main control unit 100 starts a film forming operation in accordance with a film formation start instruction input to the main control unit 100 from an input device (not shown).

  When an instruction to start film formation is given in step 3, conditioning in step S4 is performed. Conditioning is a process in which discharge is performed to stabilize film formation characteristics, and a target is sputtered to adhere sputtered particles to the inner wall of the chamber.

  Here, the conditioning will be described in more detail. FIG. 11 is a diagram showing a procedure for performing conditioning using the sputter deposition apparatus 1. Specifically, step number, time in each process (set time), target shutter position (open, closed), substrate shutter position (open, closed), target applied power, Ar gas flow rate, and nitrogen gas flow rate, Is shown. These procedures are stored in the storage device 63 and are continuously executed by the main control unit 100.

  A film forming procedure will be described with reference to FIG. First, a gas spike is performed (S1101). By this step, the pressure in the chamber is increased, and a state in which discharge is easily started in the next plasma ignition step is created. In this condition, the target shutter 14 and the substrate shutter 19 are closed, the nitrogen gas flow rate is not introduced, and the argon gas flow rate is 400 sccm. The argon gas flow rate is preferably 100 sccm or more in order to facilitate ignition in the next plasma ignition step.

  Next, a plasma ignition process is performed (S1102). While maintaining the shutter position and gas conditions, 1000 W DC power is applied to the Ti target to generate plasma (plasma ignition). By using this gas condition, it is possible to prevent the generation failure of plasma that tends to occur at a low pressure.

  Next, pre-sputtering (S1103) is performed. In pre-sputtering, the gas condition is changed to 100 sccm of argon while maintaining the power applied to the target (target applied power). This procedure can maintain the discharge without losing the plasma.

  Next, conditioning 1 (S1104) is performed. In conditioning 1, the target shutter 14 is opened while the target applied power, the gas flow rate condition, and the position of the substrate shutter 19 are kept closed. By doing so, the shield inner wall can be covered with a low-stress film by adhering sputtered particles from the Ti target to the chamber inner wall including the shield inner wall. Therefore, it is possible to prevent the sputtered film from being peeled off from the shield, so that it is possible to prevent the peeled film from scattering into the chamber and falling onto the device, thereby deteriorating the characteristics of the product.

  Next, a gas spike (S1105) is performed again. In the gas spike process, the application of power to the target is stopped, the argon gas flow rate is 200 sccm, and the nitrogen gas flow rate is 10 sccm. The argon gas flow rate is preferably a flow rate larger than the conditioning 2 step (S1108) described later (for example, 100 sccm or more) in order to facilitate ignition in the next plasma ignition step. Further, in the conditioning 2 step (S1108) described later, since the nitride film is formed by the reactive sputtering method in which nitrogen gas is introduced, the introduction of nitrogen gas from the gas spike step also has an effect of preventing a rapid gas flow rate change. .

  Next, a plasma ignition process is performed (S1106). Plasma is generated by applying DC power of 750 W to the Ti target while maintaining the shutter position and gas flow rate conditions (plasma ignition). By using this gas condition, it is possible to prevent the generation of plasma that tends to occur at a low pressure.

  Next, pre-sputtering (S1107) is performed. In pre-sputtering, the gas flow rate condition is changed to 10 sccm of argon and 10 sccm of nitrogen gas while maintaining the target applied power. This procedure can maintain the discharge without losing the plasma.

  Next, conditioning 2 (S1108) is performed. In conditioning 2, the target shutter 14 is opened while the target applied power, the gas flow rate condition, and the position of the substrate shutter 19 are kept closed. By doing this, the sputtered particles from the Ti target react with nitrogen, which is a reactive gas, and a nitride film is deposited on the inner wall of the chamber including the inner wall of the shield. Rapid changes in state can be suppressed. By suppressing the rapid change of the gas state in the chamber, the film formation in the next substrate film formation process can be performed stably from the beginning, so that there is a great improvement effect on the improvement of manufacturing stability in the device manufacturing. .

  The time required for each of the above procedures is set to an optimum value. In this embodiment, the first gas spike (S1101) is 0.1 seconds, the plasma ignition (S1102) is 2 seconds, and the pre-sputtering (S1103) is 5 seconds. Seconds, conditioning 1 (S1104) for 240 seconds, second gas spike (S1105) for 5 seconds, second plasma ignition (S1106) for 2 seconds, second pre-sputtering for 5 seconds, conditioning 2 (S1108) 180 seconds.

  Note that the second gas spike step (S1105), the subsequent plasma ignition step (S1106), and the pre-sputtering step (S1107) can be omitted. If omitted, it is desirable in that the conditioning time can be shortened. However, when the conditioning 2 step (S1108) in which nitrogen gas is added following the conditioning 1 step (S1104), which is an argon gas discharge, is performed, the properties of the plasma change greatly while continuing the discharge. Therefore, particles may increase due to the transient state. In such a case, by inserting these steps (S1105, S1106, S1107) including temporarily stopping the discharge and replacing the gas between the conditioning 1 step (S1104) and the conditioning 2 step (S1108). Since the rapid fluctuation of the plasma characteristics during conditioning can be further suppressed, the risk of generating particles can be reduced.

  In addition, it is desirable that conditioning 2 (S1108), which is reactive sputtering, is substantially the same as a film formation condition on a substrate described later. By making the film forming conditions on the substrate in the product manufacturing process substantially the same as in Conditioning 2 (S1108), the film forming on the substrate in the product manufacturing process can be performed more stably and with good reproducibility.

  Returning to FIG. 10, after conditioning (S4), Step S5 including film formation on the substrate is performed. Here, with reference to FIG. 10, the procedure for the film-forming process which comprises step S5 is demonstrated.

  First, a substrate is carried in (S501). In the substrate loading step (S501), the gate valve 42 is opened, the substrate 10 is loaded into the vacuum chamber 2 by a substrate transfer robot (not shown) and a lift mechanism (not shown), and the substrate placement surface on the substrate holder 7 is loaded. Placed on. The substrate holder 7 moves upward to the film forming position with the substrate placed thereon.

  Next, a gas spike is performed (S502). In the gas spike step (S502), the target shutter 14 and the substrate shutter 19 are closed, and argon gas, for example, 200 sccm and nitrogen gas, 10 sccm are introduced. Here, it is desirable that the amount of argon gas is larger than the amount of argon gas introduced in the film forming step (S506) to be described later from the viewpoint of ease of starting discharge. The time required for the gas spike step (S502) is, for example, about 0.1 seconds, as long as the pressure required in the next ignition step (S503) can be secured.

  Next, plasma ignition is performed (S503). In the plasma ignition process (S503), the target shutter 14 and the substrate shutter 19 remain closed, and the flow rates of argon gas and nitrogen gas remain the same as the conditions in the gas spike process (S502), and the target 4 A direct current (DC) power of 750 W is applied to generate discharge plasma in the vicinity of the sputtering surface of the target. The time required for the plasma ignition step (S503) may be as long as the plasma is ignited, for example, 2 seconds.

  Next, pre-sputtering is performed (S504). In the pre-sputtering step (S504), the target shutter 14 and the substrate shutter 19 are kept closed, the flow rate of argon gas is reduced to, for example, 10 sccm, and the flow rate of nitrogen gas is set to 10 sccm. At this time, the direct current (DC) power to the target is, for example, 750 W, and the discharge is maintained. The time required for the pre-sputtering step (S504) may be a time required for preparation for the next short conditioning, for example, 5 seconds.

  Next, short conditioning is performed (S505). In the short conditioning process (S505), the target shutter 14 is opened and opened. The substrate shutter 19 is kept closed, and the flow rate of argon gas is maintained at 10 sccm, and the flow rate of nitrogen gas is maintained at 10 sccm. At this time, the direct current (DC) power to the target is, for example, 750 W, and the discharge is maintained. In this short conditioning, a titanium nitride film is formed on the inner wall of the shield and the like, and it is effective for forming the film in a stable atmosphere in the film formation process (S506) on the next substrate. In order to increase this effect, it is desirable that film formation is performed under substantially the same conditions as the discharge conditions in the film formation step (S506) on the substrate in the next step. Note that the time required for the short conditioning step (S505) is shorter than the previous conditioning 1 (S1104) and conditioning 2 (S1108) because the atmosphere is adjusted by the previous conditioning (S4). For example, It may be about 5 to 30 seconds.

  Next, the conditions of argon gas, nitrogen gas, and DC power are maintained the same as the conditions of the short conditioning step (S505) to maintain the discharge, and the substrate shutter 19 is maintained while the target shutter 14 is kept open. The film is opened and film formation on the substrate is started (S506). That is, the film forming conditions on the substrate 10 are an argon gas flow rate of 10 sccm, a nitrogen gas flow rate of 10 sccm, and a DC power applied to the target of 750 W.

  After the power to the target 4 is stopped and the film formation S506 on the substrate is completed, the substrate unloading 507 is performed. In the substrate unloading 507, the substrate holder 7 moves downward, the gate valve 42 is opened, and the substrate 10 is unloaded by a substrate transfer robot (not shown) and a lift mechanism (not shown).

  Next, the main control unit 100 determines whether or not conditioning is necessary (S6). In the conditioning necessity determination step (S6), the main control unit 100 determines the necessity of conditioning based on the determination conditions stored in the storage device 63. If it is determined that conditioning is necessary, the process returns to step S4, and conditioning is performed again (S4). On the other hand, if it is determined in step S6 that the conditioning is not necessary by the main control unit 100, the process proceeds to the next determination of S7. In step S7, a determination is made based on whether or not an end signal is input to the main control unit 100, whether or not there is a processing substrate supplied to the apparatus, and if it is determined not to end (S7-NO), the processing is performed. Is returned to step S501, and the process from the substrate loading (S501) to the substrate unloading (S507) through the film formation (S506) is performed again. In this way, the film forming process on the product substrate is continued for a predetermined number, for example, about several hundred films.

  An example in which it is determined that the conditioning should be started in the conditioning necessity determination step (S6) will be described. After continuous processing, waiting time may occur for reasons such as product waiting time. When a standby time that requires conditioning occurs from the determination condition stored in the storage device 63, the main control unit 100 determines that conditioning is necessary, and performs the conditioning in step S4 again. By this conditioning, the upper surface of a high stress film such as TiN attached to the inner surface of the shield can be covered with a low stress film such as Ti. When TiN continuously adheres to the shield, the stress of the TiN film is high and the adhesion with the shield is weak, so that film peeling occurs and becomes particles. For this purpose, Ti sputtering is performed for the purpose of preventing film peeling.

  The Ti film has high adhesion to the shield and TiN film, and has an effect of preventing peeling of the TiN film (wall coating effect). In this case, in order to sputter the entire shield, it is effective to use a substrate shutter. According to the sputter deposition apparatus 1 according to the embodiment of the present invention, the substrate shutter 19 and the substrate peripheral cover ring 21 form a labyrinth seal, and thus conditioning is performed without depositing a sputter film on the substrate installation surface of the substrate holder. I can do it. After this conditioning, the film forming process S5 (S501 to S507) is performed again.

  As described above, conditioning is performed, and then the product processing procedure is repeated until the target lifetime. Thereafter, maintenance is performed, and after the shield and target are replaced, the initial target cleaning is repeated.

  By the above procedure, it is possible to manufacture an electronic device without preventing the film attached to the shield from being peeled off and without attaching a sputtered film to the substrate mounting surface of the substrate holder. In the present embodiment, an example in which maintenance is performed with a target life is shown, but the same operation is performed for maintenance for shield replacement. In addition, here, an example of the conditioning start when the standby time occurs has been described, but the condition for starting the conditioning (condition for determining whether conditioning is necessary) is not limited to the above example.

  FIG. 12 is a diagram illustratively explaining the condition for starting conditioning (condition for determining whether conditioning is necessary). The judgment conditions for starting conditioning are the total number of processed substrates, the total number of processed lots, the total film thickness formed, the amount of power applied to the target, and the film formation on that shield after the shield replacement This is a change in the film forming conditions accompanying the change in the amount of power applied to the target, the standby time and the electronic device to be processed.

  The start timing of conditioning can be after the end of processing of a lot (a bundle of substrates set for convenience in managing the manufacturing process, and usually 25 substrates are set as one lot). When there are a plurality of lots to be processed (processing lots), the total number of processing lots becomes the determination condition, and the processing start timing after the processing of all the lots can be set (conditioning start conditions 1, 3, 5, 7, 9, 11). Alternatively, even during the lot processing, if any of the above-described determination conditions excluding the lot-related conditions is satisfied, the processing can be interrupted and used as the conditioning start timing (conditioning start conditions 2, 4). , 6, 8, 10, 12).

  The method (1201) of determining by the total number of processed substrates has an advantage that the conditioning interval is constant even if the number of substrates constituting the lot varies. The method (1202) for determining based on the sum of the processing lots has an advantage that the conditioning time can be predicted when the process management is performed by the number of lots.

  The determination method (1203) based on the film thickness formed by the film forming apparatus has an advantage that conditioning can be performed at an appropriate timing when film peeling from the shield depends on an increase in film thickness. The method (1204) for determining based on the integrated power of the target has an advantage that conditioning can be performed at an appropriate timing when the target surface changes due to the film formation process. The method (1205) for determining by the integrated power per shield has an advantage that conditioning can be performed at an appropriate timing even when the cycle of shield replacement and target replacement is shifted. The method (1206) for determining by the standby time is an effect of stabilizing the film formation characteristics in a good state when there is a concern that the residual gas concentration or temperature in the film formation chamber changes during the standby time and the film formation characteristics deteriorate. There is. The method (1207) using the change of the film formation condition (product manufacturing condition) on the substrate as the determination condition has an effect that the film can be stably formed on the substrate even when the film formation condition is changed. When the film forming conditions are changed, the state of the shield inner wall surface and the target surface changes. These changes lead to variations in gas composition and electrical properties due to the gettering performance of the shield inner wall surface and the target surface, and as a result, cause variations in deposition properties on the substrate within the lot. The method (1207) using the change of the film formation condition (product manufacturing condition) on the substrate as the determination condition has an effect of suppressing such a defect.

  The method of performing conditioning after lot processing has an effect of preventing the lot processing from being interrupted when the production process is managed in units of lots (conditioning start conditions 1, 3, 5, 7, 9, 11 ). The method of interrupting the conditioning during the lot processing has an advantage that it can be carried out at an accurate conditioning timing (conditioning start conditions 2, 4, 6, 8, 10, 12). When the change of the film forming condition becomes the determination condition, the conditioning is performed before the lot processing (conditioning start condition 13).

  FIG. 13 is a diagram showing a result of measuring the number of particles adhering on the substrate once a day when the process of FIG. 10 is performed using the sputter deposition apparatus 1 according to the embodiment of the present invention. The horizontal axis represents the measurement date, and the vertical axis represents the number of particles of 0.09 μm or more observed on a 300 mm diameter silicon substrate. The number of particles was measured using a surface inspection apparatus “SP2” (trade name) manufactured by KLA Tencor. This data shows that a very good number of particles of 10 or less per substrate could be maintained over a relatively long period of 16 days.

  The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to make the scope of the present invention public, the following claims are attached.

Claims (1)

A shielding member used in a vacuum vessel including a target holder for holding a target and a substrate holder connected to a rotation mechanism for placing a substrate,
It is arranged in the vicinity of the substrate holder, and is closed by the first driving means so as to shield between the substrate holder and the target holder or opened between the substrate holder and the target holder. A first member for,
And a second member installed on the surface of the substrate holder and on the outer periphery of the substrate,
Concentric first projections having at least one ring shape extending in the second member direction are formed on the first member,
At a position where the substrate holder is close to the first member, the concentric first shape has at least one ring shape that fits in a non-contact state with the first protrusion and extends in the direction of the first member. 2. A shielding member, wherein two protrusions are formed on the second member.