Plasma Processing Systems

Abstract

To provide a technique that can improve productivity.SOLUTION: A plasma processing system comprises: a process module; a first conveying module that is connected with the process module; a conveying device that is provided inside the first conveying module, and is used for conveyance of a focus ring from the first conveying module to the process module; and a position detection sensor that is provided at a position on a conveyance path of the focus ring conveyed by the conveying device, where the focus ring can be detected. The position detection sensor detects the position of the focus ring on the basis of output generated by the passage of the focus ring through the position detection sensor during the conveyance of the focus ring from the first conveying module to the process module.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a plasma processing system. [Background technology]

[0002] A plasma processing apparatus is known in which a substrate is placed on a mounting table provided inside a processing chamber and plasma processing is performed. Such a plasma processing apparatus has consumable parts that gradually wear out as the plasma processing is repeatedly performed (see, for example, Patent Document 1).

[0003] An example of a consumable part is a focus ring that is provided around the substrate on the upper surface of the mounting table. The focus ring is worn down by exposure to plasma and therefore needs to be replaced periodically.

[0004] Therefore, conventionally, the processing chamber is periodically opened to the atmosphere, and an operator manually replaces the focus ring. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-253541 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the method of opening the processing chamber to the atmosphere, it takes a long time to replace the focus ring, and substrates cannot be processed in the processing chamber during the focus ring replacement, resulting in reduced productivity.

[0007] The present disclosure provides a technique that can improve productivity. [Means for solving the problem]

[0008] A plasma processing system according to one aspect of the present disclosure includes a first transfer module, a first transfer device provided inside the first transfer module, a process module connected to the first transfer module, a first load lock module connected to the first transfer module, a second load lock module connected to the first transfer module, a second transfer module connected to the first load lock module and the second load lock module and to which a container for storing unused rings is connected, a second transfer device provided inside the second transfer module, and a controller, wherein the controller controls the first transfer device to (a) transfer used rings unloaded from the process module toward the first load lock module without opening the process module to the atmosphere, the controller controls the second transfer device to (b) load the unused rings stored in the container connected to the second transfer module into the second load lock module, and the controller controls the first transfer device to (c) load the unused rings unloaded from the second load lock module into the process module after (b) without opening the process module to the atmosphere. The control unit controls the first transfer device to (d) unload the substrate from the process module before (a). . [Effects of the Invention]

[0009] According to the present disclosure, productivity can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram illustrating a plasma processing system according to an embodiment; [Figure 2] 1 is a schematic cross-sectional view showing a plasma processing apparatus according to an embodiment; [Figure 3] 1 is a flowchart illustrating a focus ring replacement method according to an embodiment. [Figure 4] FIG. 2 is a diagram for explaining the processing unit side transfer device of FIG. 1. [Figure 5] FIG. 2 is a diagram showing a state in which the processing unit side transfer device of FIG. 1 holds a wafer. [Figure 6] FIG. 2 is a diagram showing a state in which the processing unit side transport device in FIG. 1 holds a focus ring. [Figure 7] FIG. 2 is a diagram for explaining the position detection sensor of FIG. 1; [Figure 8] FIG. 10 is a diagram for explaining a method for correcting the position of a wafer. [Figure 9] 5A and 5B are diagrams for explaining a method for correcting the position of a focus ring. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0012] In one embodiment of the focus ring replacement method, a transfer device is used to remove a focus ring from a processing chamber, clean the processing chamber, and then the transfer device is used to return the focus ring to the processing chamber, all without opening the processing chamber to the atmosphere. The focus ring is a component provided inside the processing chamber and placed on the upper surface of a mounting table on which a substrate is placed, surrounding the periphery of the substrate, for the purpose of improving etching uniformity.

[0013] A focus ring replacement method according to an embodiment of the present invention is applicable to various plasma processing apparatuses in which a focus ring is used.

[0014] (Plasma Processing System) First, a plasma processing system according to one embodiment of the present invention will be described below. Fig. 1 is a schematic diagram showing the configuration of a plasma processing system according to one embodiment.

[0015] As shown in FIG. 1, the plasma processing system is a cluster tool having a processing unit PU and a transfer unit TU.

[0016] The processing unit PU is a unit that performs predetermined processes such as film formation and etching on substrates such as semiconductor wafers (hereinafter referred to as "wafers W"). The processing unit PU has process modules PM1 to PM6, a transfer module TM, and load lock modules LL1 and LL2. Note that the number of process modules PM and load lock modules LL is not limited to the above.

[0017] The process modules PM1 to PM6 are connected to the periphery of the transfer module TM and perform predetermined processes such as film formation and etching on the wafers W. The process modules PM1 to PM6 may perform the same type of process or different types of processes.

[0018] Each of the process modules PM1 to PM6 is provided with a mounting table 3 for mounting a wafer W. Although not shown, each of the process modules PM1 to PM6 is also provided with a gas introduction system for introducing a purge gas, a gas introduction system for introducing a processing gas, and an exhaust system capable of vacuum drawing.

[0019] In the process modules PM1 to PM6, predetermined processing is performed on the wafer W based on a recipe indicating processing steps stored in advance in a memory unit or the like of the control unit CU. Also, in the process modules PM1 to PM6, the focus ring is replaced at a predetermined timing stored in advance in a memory unit or the like of the control unit CU. Details of the process modules PM and the focus ring replacement method will be described later.

[0020] The transfer module TM is shaped like a hexagon, with a pair of opposing sides longer than the other sides. The two shorter sides at the front end of the transfer module TM are connected to process modules PM3 and PM4 via gate valves G3 and G4, respectively. The two shorter sides at the base end of the transfer module TM are connected to load lock modules LL1 and LL2 via gate valves G7 and G8, respectively. The process modules PM1 and PM2 are connected to one long side of the transfer module TM via gate valves G1 and G2, respectively. The process modules PM5 and PM6 are connected to the other long side of the transfer module TM via gate valves G5 and G6, respectively.

[0021] The transfer module TM has the function of transporting (loading in and out) wafers W and focus rings between the process modules PM1 to PM6 and between the process modules PM1 to PM6 and the load lock modules LL1 and LL2. Although not shown, the transfer module TM is provided with, for example, a gas introduction system for introducing a purge gas and an exhaust system capable of vacuum drawing.

[0022] Inside the transfer module TM, a processing unit side transfer device TR1 is provided for transferring wafers W and focus rings between the process modules PM1 to PM6 and the load lock modules LL1 and LL2. Details of the processing unit side transfer device TR1 will be described later.

[0023] Position detection sensors S11 and S12 are provided near the gate valve G1 of the transfer module TM on the transfer path of the wafer W and focus ring transferred from the transfer module TM to the process module PM1. The position detection sensors S11 and S12 are positioned so that the distance between them is smaller than the outer diameter of the wafer W and smaller than the inner diameter of the focus ring. This allows the positions of the wafer W and focus ring transferred to the process module PM1 to be corrected. The position detection sensors S11 and S12 will be described in detail later.

[0024] Similarly, position detection sensors are provided near the gate valves G2 to G6 of the transfer module TM on the transfer paths of the wafers W and focus rings transferred from the transfer module TM to the process modules PM2 to PM6. That is, the transfer module TM is provided with position detection sensors S11, S12, S21, S22, S31, S32, S41, S42, S51, S52, S61, and S62.

[0025] The load lock modules LL1 and LL2 are connected to the transfer module LM via gate valves G9 and G10, respectively. The load lock modules LL1 and LL2 have the function of temporarily holding the wafer W transferred from the transfer module LM and transferring it to the transfer module TM after adjusting the pressure. The load lock modules LL1 and LL2 also have the function of temporarily holding the wafer W transferred from the transfer module TM and transferring it to the transfer module LM after adjusting the pressure.

[0026] Inside the load lock modules LL1 and LL2, there is provided a transfer table on which a wafer W can be placed. Furthermore, although not shown, each of the load lock modules LL1 and LL2 is provided with an exhaust system capable of purging and exhausting particles such as residues.

[0027] In such a processing unit PU, the spaces between the process modules PM1 to PM6 and the transfer module TM, and between the transfer module TM and the load lock modules LL1 and LL2 can be opened and closed airtightly, respectively.Furthermore, the spaces between the transfer module LM and the load lock modules LL1 and LL2 can also be opened and closed airtightly, respectively.

[0028] The transfer unit TU is a unit that transfers the wafer W between a FOUP (Front Opening Unified Pod) (to be described later) and the processing unit PU, and includes a transfer module LM.

[0029] The transfer module LM is formed in a rectangular shape. A plurality of load ports LP1 to LP3 are arranged side by side on one long side of the transfer module LM. Each of the load ports LP1 to LP3 is capable of mounting a FOUP. Note that FIG. 1 shows a case where a FOUP is mounted on all of the load ports LP1 to LP3. A FOUP is a container that can accommodate, for example, 25 wafers W mounted in multiple stages at equal intervals. The FOUP has an airtight structure, the interior of which is filled with, for example, N2 gas. The FOUP is connected to the transfer module LM via opening / closing doors D1 to D3. Note that the number of load ports LP is not limited to the above.

[0030] An aligner AU is provided on one short side of the transfer module LM. The aligner AU has a rotary stage on which the wafer W is placed and an optical sensor that optically detects the outer periphery of the wafer W. The aligner AU aligns the wafer W by detecting, for example, an orientation flat, a notch, etc. of the wafer W.

[0031] Inside the transfer module LM, a transfer unit-side transfer device TR2 is provided for transferring wafers W and focus rings between the load lock modules LL1 and LL2, the FOUP, and the aligner AU. The transfer unit-side transfer device TR2 has a transfer arm that is rotatably attached to a base 231 by a rotation mechanism, and is slidable along the longitudinal direction of the transfer module LM by a slide mechanism. The transfer arm of the transfer unit-side transfer device TR2 is, for example, a double-arm mechanism having a pair of articulated arms, as shown in FIG. 1. The transfer arm shown in FIG. 1 includes a first arm 211 and a second arm 221, which are extendable articulated arms arranged side by side above and below.

[0032] The slide mechanism of the transport unit-side transport device TR2 includes, for example, a linear motor. Specifically, a guide rail 232 is provided inside the transport module LM along the longitudinal direction, and a base 231 to which the transport arm is attached is provided slidably along the guide rail 232. The base 231 and the guide rail 232 are each provided with a mover and a stator of a linear motor, and a linear motor drive mechanism 233 for driving the linear motor is provided at the end of the guide rail 232. A control unit CU is connected to the linear motor drive mechanism 233. This drives the linear motor drive mechanism 233 based on a control signal from the control unit CU, and the transport unit-side transport device TR2 moves together with the base 231 along the guide rail 232 in the direction of the arrow. Note that the slide mechanism of the transport unit-side transport device TR2 is not limited to the above and may include other mechanisms.

[0033] The first arm 211 and the second arm 221, which are the transfer arms of the transfer unit side transfer device TR2, have picks 212 and 222 at their tips, respectively, and are capable of holding two wafers W or two focus rings at a time. This allows the wafers W and focus rings to be exchanged when transferring them to, for example, load lock modules LL1 and LL2, FOUP, or aligner AU. Note that the transfer device may hold and transfer one wafer W and one focus ring at a time. Furthermore, the number of transfer arms of the transfer unit side transfer device TR2 is not limited to the above, and may be, for example, a single-arm mechanism having only one arm.

[0034] The transport unit-side transport device TR2 also has a rotation motor, an extension motor, and an elevation motor (not shown) for rotating, extending, and elevating the transport arm. Each motor is connected to the control unit CU, and can control the transport arm of the transport unit-side transport device TR2 based on control signals from the control unit CU.

[0035] The plasma processing system includes a control unit CU that controls each part of the plasma processing system, such as the processing unit side transfer device TR1, the transfer unit side transfer device TR2, the gate valves G1 to G10, the opening / closing doors D1 to D3, and the aligner AU.

[0036] (Plasma processing equipment) Next, a plasma processing apparatus according to one embodiment of the present invention will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view showing the plasma processing apparatus according to one embodiment. The plasma processing apparatus shown in Fig. 2 is an apparatus that can be used as process modules PM1 to PM6 in the plasma processing system described above.

[0037] 2, the plasma processing apparatus has a substantially cylindrical processing chamber 10. The inner wall surface of the processing chamber 10 is formed of, for example, anodized aluminum. The processing chamber 10 is grounded.

[0038] A gas shower head 2 for introducing a processing gas is provided in the processing chamber 10. The gas shower head 2 functions as an upper electrode. A mounting table 3 is provided inside the processing chamber 10 so as to face the gas shower head 2. The mounting table 3 functions as a lower electrode.

[0039] A plurality of gas discharge ports 22 are formed on the lower surface of the gas shower head 2 (upper electrode), which communicate with each other via a gas supply path 21 and a buffer chamber 21a. A processing gas is discharged from the plurality of gas discharge ports 22 toward the wafer W placed on the mounting table 3. The base end of the gas supply path 21 is connected to a gas introduction system 23.

[0040] The gas introduction system 23 has a supply source of a process gas used in a film formation process on the wafer W, and a supply source of a process gas used in an etching process on the wafer W. The gas introduction system 23 also has a supply source of a process gas used in a cleaning process on the process chamber 10, and a supply source of a process gas used in a seasoning process on the process chamber 10. The gas introduction system 23 has supply control devices such as valves and flow rate adjusters, and can supply a process gas into the process chamber 10 at a predetermined flow rate.

[0041] A high frequency power supply unit 26 for supplying high frequency power is connected to the upper electrode via a matching box 25. The upper electrode is insulated from the sidewall of the processing chamber 10 by an insulating member 27.

[0042] The mounting table 3 includes a main body 30 and an electrostatic chuck 31 .

[0043] The main body 30 is formed of a conductive material such as aluminum. A coolant flow path (not shown) that functions as a temperature control mechanism is provided inside the main body 30. The temperature of the wafer W held by the electrostatic chuck 31 is controlled by adjusting the temperature of the coolant supplied to the coolant flow path.

[0044] An electrostatic chuck 31 capable of attracting both the wafer W and a focus ring FR disposed to surround the wafer W is provided on the top of the main body 30. A convex substrate mounting portion 32 is formed in the upper center of the electrostatic chuck 31, and the upper surface of the substrate mounting portion 32 forms a substrate mounting surface 33 on which the wafer W is mounted. The upper surface of a lower portion around the periphery of the substrate mounting surface 33 forms a focus ring mounting surface 34 on which the focus ring FR is mounted.

[0045] The electrostatic chuck 31 has an electrode 35 interposed between insulating materials. The electrode 35 extends not only below the substrate mounting surface 33 but also below the focus ring mounting surface 34 so as to be able to attract both the wafer W and the focus ring FR.

[0046] A predetermined DC voltage is applied to the electrostatic chuck 31 from a DC power supply 37 connected to the electrode 35 via a switch 36. As a result, the wafer W and the focus ring FR are electrostatically attracted to the electrostatic chuck 31. Note that, as shown in FIG. 2, for example, the substrate mounting portion 32 is formed to have a diameter smaller than the diameter of the wafer W so that the edge portion of the wafer W protrudes beyond the substrate mounting portion 32 when the wafer W is mounted thereon.

[0047] The mounting table 3 is provided with a heat transfer gas supply unit 38 that supplies a heat transfer gas (for example, helium (He) gas) to the rear surface of the wafer W and the rear surface of the focus ring FR separately.

[0048] The heat transfer gas supply unit 38 includes a first heat transfer gas supply unit 38a that supplies a first heat transfer gas to the back surface of the wafer W placed on the substrate mounting surface 33, and a second heat transfer gas supply unit 38b that supplies a second heat transfer gas to the back surface of the focus ring FR placed on the focus ring mounting surface 34.

[0049] The focus ring FR is placed on the electrostatic chuck 31. A step is formed on the upper surface of the focus ring FR, and the outer periphery is higher than the inner periphery. The inner periphery of the focus ring FR is formed to fit under the outer periphery of the wafer W, which protrudes outward beyond the mounting table 3. In other words, the inner diameter of the focus ring FR is smaller than the outer diameter of the wafer W. This protects the electrostatic chuck 31 from plasma when etching the wafer W.

[0050] A high-frequency power supply unit 40 that applies bias power via a matching box 39 is connected to the mounting table 3. Furthermore, inside the mounting table 3, there are provided lift pins (not shown) that can transfer the wafer W and focus ring FR to and from the processing unit side transfer device TR1 shown in FIG. 1. When the processing unit side transfer device TR1 transfers the focus ring FR, the lift pins are raised to separate the focus ring FR from the mounting table 3.

[0051] An opening 13 having a gate valve G1 that can be opened and closed is formed in the sidewall of the processing chamber 10. The wafer W and the focus ring FR are transferred through the opening 13.

[0052] A deposit shield 41 is detachably provided along the inner wall of the processing chamber 10. The deposit shield 41 is also provided on the outer periphery of the mounting table 3. The deposit shield 41 prevents reaction products generated by etching from adhering to the inner wall surface of the processing chamber 10, and is formed by coating aluminum with ceramics such as Y2O3, for example.

[0053] A baffle plate 42 with many exhaust holes is provided around the mounting table 3 to uniformly exhaust the inside of the processing chamber 10. The baffle plate 42 is formed, for example, by coating aluminum with ceramics such as Y2O3. A vacuum pump 12, such as a turbomolecular pump or a dry pump, is connected below the baffle plate 42 via an exhaust pipe 11.

[0054] The plasma processing apparatus has a control unit 50 that controls each unit. The control unit 50 is, for example, a computer having a CPU and a program. The program contains a group of steps (commands) for controlling, for example, the supply of gases from the gas introduction system 23 and the supply of power from the high-frequency power supply units 26 and 40 to perform film formation processing and etching processing on the wafer W by the plasma processing apparatus. The program is stored in a storage medium, for example, a hard disk, a compact disk, a memory card, or the like, and is installed into the computer from the storage medium.

[0055] (How to replace the focus ring) Next, a focus ring replacement method according to one embodiment of the present invention will be described with reference to Fig. 3. Fig. 3 is a flowchart illustrating the focus ring replacement method according to one embodiment.

[0056] The following describes an example of replacing the focus ring FR mounted on the mounting table 3 of the aforementioned process module PM1. Specifically, the description will be given of a case where a focus ring used in process module PM1 is stored in a FOUP and replaced with an unused focus ring previously stored in the FOUP. Note that the focus rings FR mounted on the mounting tables 3 of process modules PM2 to PM6 other than process module PM1 can also be replaced using a similar method. The focus ring replacement method of one embodiment of the present invention is performed by a control unit CU controlling various components of the plasma processing system.

[0057] 3, the focus ring replacement method according to one embodiment includes a wear level determination step S10, a replacement possibility determination step S20, a first cleaning step S30, a removal step S40, a second cleaning step S50, a loading step S60, and a seasoning step S70. Each step will be described below.

[0058] The wear level determination step S10 is a step for determining whether the focus ring FR mounted on the mounting table 3 of the process module PM1 needs to be replaced. In the wear level determination step S10, the control unit CU determines whether the focus ring FR mounted on the mounting table 3 of the process module PM1 needs to be replaced. Specifically, the control unit CU determines whether the focus ring FR needs to be replaced based on, for example, the RF integrated time, the RF integrated power, and the integrated value of a specific step of the recipe. The RF integrated time is the integrated value of the time over which high-frequency power is supplied to the process module PM1 during a specific plasma process. The RF integrated power is the integrated value of the high-frequency power supplied to the process module PM1 during a specific plasma process. The integrated value of a specific step of the recipe is the integrated value of the time over which high-frequency power is supplied or the integrated value of the high-frequency power in a step of the process performed in the process module PM1 in which the focus ring FR is removed. The RF cumulative time, RF cumulative power, and cumulative values ​​of a specific step of the recipe are values ​​calculated starting from the point when the focus ring FR was replaced, such as when the device was installed or when maintenance was performed.

[0059] When determining whether or not the focus ring FR needs to be replaced based on the RF integrated time, the control unit CU determines that the focus ring FR needs to be replaced if the RF integrated time reaches a threshold. Conversely, the control unit CU determines that the focus ring FR does not need to be replaced if the RF integrated time does not reach the threshold. The threshold is a value determined based on the type of material, etc., of the focus ring FR through preliminary experiments, etc.

[0060] When determining whether or not the focus ring FR needs to be replaced based on the RF integrated power, the control unit CU determines that the focus ring FR needs to be replaced if the RF integrated power reaches a threshold. In contrast, the control unit CU determines that the focus ring FR does not need to be replaced if the RF integrated power does not reach the threshold. The threshold is a value determined based on the type of material, etc., of the focus ring FR through preliminary experiments, etc.

[0061] When determining whether the focus ring FR needs to be replaced based on the integrated value of a specific step of the recipe, the control unit CU determines that the focus ring FR needs to be replaced if the RF integrated time or RF integrated power in the specific step reaches a threshold. In contrast, the control unit CU determines that the focus ring FR does not need to be replaced if the RF integrated time or RF integrated power in the specific step does not reach the threshold. When determining whether the focus ring FR needs to be replaced based on the integrated value of a specific step of the recipe, the timing to replace the focus ring FR can be calculated based on the step in which high-frequency power is applied and the focus ring FR is scraped. Therefore, the timing to replace the focus ring FR can be calculated with particularly high accuracy. The threshold is a value determined based on the type of material, etc., of the focus ring FR through preliminary experiments, etc.

[0062] If it is determined in wear level determination step S10 that the focus ring FR mounted on the mounting table 3 of the process module PM1 needs to be replaced, the control unit CU performs replacement determination step S20. If it is determined in wear level determination step S10 that the focus ring FR mounted on the mounting table 3 of the process module PM1 does not need to be replaced, the control unit CU repeats wear level determination step S10.

[0063] The replacement determination step S20 is a step for determining whether the state of the plasma processing system allows replacement of the focus ring FR. In the replacement determination step S20, the control unit CU determines whether the state of the plasma processing system allows replacement of the focus ring FR. Specifically, for example, when no wafer W is being processed in the process module PM1 in which the focus ring FR is to be replaced, the control unit CU determines that the focus ring FR is replaceable. In contrast, when a wafer W is being processed in the process module PM1, the control unit CU determines that the focus ring FR is not replaceable. Alternatively, the control unit CU may determine that the focus ring FR is replaceable when, for example, processing of a wafer W of the same lot as the wafer W being processed in the process module PM1 in which the focus ring FR is to be replaced has been completed. In this case, the control unit CU determines that the focus ring FR is not replaceable until processing of a wafer W of the same lot as the wafer W being processed in the process module PM1 has been completed.

[0064] If it is determined in replacement possibility determining step S20 that the state of the plasma processing system is such that replacement of the focus ring FR is possible, the control unit CU performs a first cleaning step S30. If it is determined in replacement possibility determining step S20 that the state of the plasma processing system is such that replacement of the focus ring FR is not possible, the control unit CU repeats replacement possibility determining step S20.

[0065] The first cleaning step S30 is a step for cleaning the process module PM1. In the first cleaning step S30, the controller CU controls the gas supply system, exhaust system, power supply system, etc. to perform the cleaning process of the process module PM1. The cleaning process is a process for removing deposits generated in the process module PM1 by using plasma of a processing gas or the like to stabilize the inside of the process module PM1 in a clean state. By performing the first cleaning step S30, it is possible to prevent deposits from being blown up in the processing chamber 10 when the focus ring FR is unloaded from the mounting table 3 in the unloading step S40. Examples of the processing gas that can be used include oxygen (O2) gas, fluorocarbon (CF2)-based gas, nitrogen (N2) gas, argon (Ar) gas, He gas, or a mixture of two or more of these gases. Depending on the processing conditions, the cleaning process of the process module PM1 may be performed with a wafer W, such as a dummy wafer, placed on the electrostatic chuck of the mounting table 3 to protect the electrostatic chuck. Note that the first cleaning step S30 does not need to be performed if there is no deposit in the processing chamber 10, or if there is no possibility of deposits being rolled up. Furthermore, if the focus ring FR is attached to the mounting table 3 by the electrostatic chuck, a charge removal process is performed before the next unloading step S40.

[0066] In the unloading step S40, the focus ring FR is unloaded from the process module PM1 without opening the process module PM1 to the atmosphere. In the unloading step S40, the controller CU controls the various components of the plasma processing system to unload the focus ring FR from the process module PM1 without opening the process module PM1 to the atmosphere. Specifically, the gate valve G1 is opened, and the processing unit-side transfer device TR1 unloads the focus ring FR mounted on the mounting table 3 inside the process module PM1 from the process module PM1. Next, the gate valve G8 is opened, and the processing unit-side transfer device TR1 places the focus ring FR unloaded from the process module PM1 on the transfer table of the load lock module LL2. Next, the gate valve G8 is closed, and after adjusting the pressure inside the load lock module LL2, the gate valve G10 is opened, and the transfer unit-side transfer device TR2 transfers the focus ring FR mounted on the transfer table to the transfer module TM. Subsequently, the door D3 is opened, and the transfer unit side transfer device TR2 places the focus ring FR into the FOUP placed on the load port LP3.

[0067] The second cleaning step S50 is a step of cleaning the surface (focus ring mounting surface 34) of the mounting table 3 of the process module PM1 on which the focus ring FR is mounted. In the second cleaning step S50, the controller CU controls the gas supply system, exhaust system, power supply system, etc. to clean the surface of the mounting table 3 of the process module PM1 on which the focus ring FR is mounted. The cleaning process in the second cleaning step S50 can be performed, for example, in the same manner as the first cleaning step S30. That is, the process gas can be, for example, O gas, CF-based gas, N gas, Ar gas, He gas, or a mixture of two or more of these gases. Depending on the processing conditions, the cleaning process of the process module PM1 may be performed with a wafer W, such as a dummy wafer, mounted on the electrostatic chuck of the mounting table 3 to protect the electrostatic chuck.

[0068] In the loading step S60, the focus ring FR is loaded into the process module PM1 without opening the process module PM1 to the atmosphere and placed on the mounting table 3. In the loading step S60, the controller CU controls the various components of the plasma processing system to load the focus ring FR into the process module PM1 without opening the process module PM1 to the atmosphere. Specifically, for example, the open / close door D3 is opened, and the transfer unit-side transfer device TR2 unloads the unused focus ring FR housed in the FOUP placed on the load port LP3. Next, the gate valve G9 is opened, and the transfer unit-side transfer device TR2 places the unused focus ring FR on the transfer table of the load lock module LL1. Next, the gate valves G7 and G1 are opened, and the processing unit-side transfer device TR1 unloads the unused focus ring FR from the transfer table of the load lock module LL1, loads it into the process module PM1, and places it on the mounting table 3.

[0069] The seasoning step S70 is a step in which the process module PM1 is seasoned. In the seasoning step S70, the control unit CU performs the seasoning process on the process module PM1 by controlling the gas introduction system, exhaust system, power introduction system, etc. The seasoning process is a process for stabilizing the temperature and the state of deposits in the process module PM1 by performing a predetermined plasma process. In the seasoning step S70, after the seasoning process on the process module PM1, a quality control wafer may be loaded into the process module PM1 and a predetermined process may be performed on the quality control wafer. This makes it possible to check whether the state of the process module PM1 is normal.

[0070] The focus ring FR can be replaced by following the steps above.

[0071] As described above, in the focus ring replacement method according to one embodiment of the present invention, the processing unit transfer device TR1 removes the focus ring FR from the processing chamber 10 without opening the processing chamber 10 to the atmosphere, cleans the processing chamber 10, and then the processing unit transfer device TR1 loads the focus ring FR back into the processing chamber 10. This eliminates the need for an operator to manually replace the focus ring FR. This reduces the time required for focus ring replacement and improves productivity. Furthermore, cleaning the focus ring mounting surface 34 before loading the focus ring FR reduces the presence of deposits between the focus ring FR and the focus ring mounting surface 34. This improves contact between the focus ring FR and the focus ring mounting surface 34, thereby maintaining good temperature controllability of the focus ring FR.

[0072] (Processing unit side transport device) Next, an example of the processing unit side transfer device TR1 will be described with reference to Fig. 4. Fig. 4 is a diagram for explaining the processing unit side transfer device of Fig. 1.

[0073] First, an example of the slide mechanism of the processing unit side transfer device TR1 will be described. The transfer arms (first arm 111, second arm 121) of the processing unit side transfer device TR1 are attached to a base 131, for example, as shown in FIG. 4(a). The base 131 is slidable on guide rails 132a and 132b in the direction of the Y-axis (the longitudinal direction of the transfer module TM), which is the slide axis. Then, for example, a ball screw 134 driven by a Y-axis motor 133 is screwed into the base 131, and the slide drive of the transfer arm of the processing unit side transfer device TR1 can be controlled by controlling the drive of the Y-axis motor 133.

[0074] Next, an example of a rotation mechanism of the processing unit side transfer device TR1 will be described. The transfer arms (first arm 111, second arm 121) of the processing unit side transfer device TR1 are attached to a base 131 via a rotating plate 135 that is rotatable in the direction of the θ-axis, which is a rotation axis, as shown in Fig. 4, for example. The rotating plate 135 is driven by a θ-axis motor 136 that is provided on the base 131, for example. Thus, by controlling the drive of the θ-axis motor 136, the rotation drive of the transfer arms of the processing unit side transfer device TR1 can be controlled.

[0075] The first arm 111 and the second arm 121, which are the transfer arms of the processing unit side transfer device TR1, are equipped with picks 112 and 122 at their tips, respectively, so that they can hold two wafers W or two focus rings FR at a time. This allows the wafers W or focus rings FR to be exchanged when being transferred to, for example, the process modules PM1 to PM6 or the load lock modules LL1 and LL2. The number of transfer arms of the processing unit side transfer device TR1 is not limited to the above, and may be, for example, a single-arm mechanism having only one arm.

[0076] The processing unit side transport device TR1 also has an extension motor (not shown) for extending and retracting the transport arm. The extension motor is attached, for example, below the θ-axis motor 136 and can be controlled independently of the θ-axis motor 136. In addition to the motors described above, an elevation motor (not shown) for raising and lowering the transport arm may also be provided as a motor for driving the processing unit side transport device TR1.

[0077] The θ-axis motor 136, the Y-axis motor 133, and the like for driving the processing unit side transport device TR1 are each connected to the control unit CU, and are controlled to be driven based on commands from the control unit CU.

[0078] 1, a flexible arm 137 is connected to the base 131 of the processing unit-side transport device TR1, for example, to pass wiring for the θ-axis motor 136 and the like. The flexible arm 137 is, for example, a cylindrical arm mechanism. The flexible arm 137 is connected airtight, and its interior communicates with the atmosphere via a hole formed in the bottom of the transfer module TM. As a result, even if the inside of the transfer module TM is in a vacuum state, the inside of the flexible arm 137 is at atmospheric pressure, preventing damage to the wiring, etc.

[0079] In this way, the processing unit side transfer device TR1 can slide along the guide rails 132a and 132b and extend and retract the transfer arm, thereby transferring the wafer W and focus ring FR between the process modules PM1 to PM6 and the load lock modules LL1 and LL2.

[0080] Next, an example of the pick 112 of the processing unit side transfer device TR1 will be described. FIG. 5 is a diagram showing a state in which the processing unit side transfer device of FIG. 1 holds a wafer. FIG. 5(a) is a side view of the pick 112 holding a wafer W, and FIG. 5(b) is a top view of the pick 112 holding a wafer W. FIG. 6 is a diagram showing a state in which the processing unit side transfer device of FIG. 1 holds a focus ring. FIG. 6(a) is a side view of the pick 112 holding a focus ring FR, and FIG. 6(b) is a top view of the pick 112 holding the focus ring FR. Note that although the pick 112 will be described as an example in FIGS. 5 and 6, the same can be said for the pick 122.

[0081] 5, the pick 112 is formed with a plurality of (e.g., three) protrusions 113 that hold the outer peripheral edge of the wafer W. The protrusions 113 are, for example, frustoconical in shape and are arranged along the outer peripheral edge of the wafer W. The protrusions 113 abut against the outer peripheral edge of the wafer W at tapered portions 114 of the truncated cone, thereby preventing the wafer W from shifting relative to the pick 112. The protrusions 113 are formed, for example, from an elastomer.

[0082] 6, the protrusion 113 can hold the focus ring FR by abutting the truncated cone-shaped upper surface 115 against the lower surface of the focus ring FR. This is because, as described above, the inner diameter of the focus ring FR is smaller than the outer diameter of the wafer W. In this way, the processing unit side transfer device TR1 can hold the wafer W and the focus ring FR with one pick 112.

[0083] As described above, pick 112 holds wafer W at tapered portion 114 of protrusion 113 and focus ring FR at upper surface 115 of protrusion 113, so that focus ring FR can be held without increasing the length of pick 112. This prevents the tip of pick 112 from contacting other portions (e.g., the inner wall surface of a FOUP) when transferring wafer W or focus ring FR with pick 112. Note that although an example in which there are three protrusions 113 has been described in FIGS. 5 and 6, the number of protrusions 113 is not limited to this.

[0084] Furthermore, when the processing unit side transfer device TR1 rotates while holding the focus ring FR, it is preferable that the rotation radius be minimized. This prevents the focus ring FR held by the pick 112 from contacting other parts. Furthermore, when the two picks 112 and 122 rotate on approximately the same plane, even if one pick 112 holds the wafer W and the other pick 122 holds the focus ring FR, the wafer W and the focus ring FR can be prevented from contacting each other.

[0085] (position detection sensor) Next, an example of a position detection sensor will be described with reference to Fig. 7. Fig. 7 is a diagram for explaining the position detection sensor of Fig. 1, showing a part of a cross section taken along dashed line 1A-1B in Fig. 1.

[0086] As shown in FIG. 7, the position detection sensor S11 has a light-projecting unit 310 and a light-receiving unit 320. The light-projecting unit 310 is provided on an upper wall 330 of the transfer module TM, and the light-receiving unit 320 is provided on a lower wall 340 of the transfer module TM. The light-projecting unit 310 irradiates laser light L toward the light-receiving unit 320. The light-receiving unit 320 detects whether the laser light L irradiated from the light-projecting unit 310 is received. Note that while FIG. 7 illustrates the light-projecting unit 310 and the light-receiving unit 320 of the position detection sensor S11, the position detection sensor S12 also has a light-projecting unit and a light-receiving unit, similar to the position detection sensor S11. As a result, the laser light L irradiated from the light-projecting unit 310 of the position detection sensor S11 to the light-receiving unit 320 is blocked for a predetermined period of time by the wafer W or the focus ring FR being transported from the transfer module TM to the process module PM1. Furthermore, the laser light L irradiated from the light projecting portion to the light receiving portion of the position detection sensor S12 is blocked for a predetermined time by the wafer W or focus ring FR being transferred from the transfer module TM to the process module PM1.

[0087] Next, a method for correcting the positions of the wafer W and the focus ring FR will be described.

[0088] In a method for correcting the positions of the wafer W and the focus ring FR according to one embodiment of the present invention, the control unit CU corrects the position of the wafer W and the position of the focus ring FR using the same position detection sensor. This will be described in detail below.

[0089] First, the case where a wafer W is transferred from a transfer module TM to a process module PM1 will be described with reference to FIG. 8. FIG. 8 is a diagram for explaining a method of correcting the wafer position. FIG. 8(a) shows the relationship between the position of the wafer W and the position of the position detection sensors. FIG. 8(b) shows changes in the sensor outputs of the position detection sensors S11 and S12 when the wafer W is transferred from position P11 in FIG. 8(a) as a starting point to position P14. In FIG. 8(b), the time at position P11 is indicated as t11, the time at position P12 as t12, the time at position P13 as t13, and the time at position P14 as t14.

[0090] The control unit CU calculates the amount of deviation of the wafer W held by the pick 112 from the reference position based on the position of the wafer W detected by the position detection sensors S11 and S12 and a predetermined reference position. Subsequently, the control unit CU controls the processing unit side transfer device TR1 to place the wafer W on the mounting table 3 of the process module PM1 so as to correct the calculated amount of deviation. As a result, even if the position of the wafer W held by the pick 112 is deviated from the reference position, the wafer W can be placed at a predetermined position on the mounting table 3 of the process module PM1.

[0091] The position of the wafer W held by the pick 112 can be calculated based on changes in the sensor outputs of the position detection sensors S11 and S12 that occur when the outer peripheral edge of the wafer W passes through the position detection sensors S11 and S12. For example, as shown in FIG. 8(a), when the wafer W is transported from position P11 to position P14, the position detection sensors S11 and S12 can be calculated based on the time T1 from position P12, where the position detection sensors S11 and S12 are shaded by the wafer W, to position P13. Specifically, as shown in FIG. 8(b), the time T1 can be calculated as T1=t13-t12, using the time t12 at position P12 and the time t13 at position P13. Note that FIG. 8 shows a case where the position when the position detection sensor S11 is shaded by the wafer W is the same as the position when the position detection sensor S12 is shaded by the wafer W, but these positions may be different.

[0092] The reference position can be calculated based on, for example, the encoder positions of the rotation motor and extension motor of the first arm 111 of the processing unit side transport device TR1. Note that the method for calculating the reference position is not limited to this, and various existing methods can be used.

[0093] Next, the case of transporting the focus ring FR from the transfer module TM to the process module PM1 will be described with reference to FIG. 9. FIG. 9 is a diagram illustrating a method of correcting the position of the focus ring. FIG. 9(a) shows the relationship between the position of the focus ring FR and the position of the position detection sensors. FIG. 9(b) shows changes in the sensor outputs of the position detection sensors S11 and S12 when the focus ring FR is transported from position P21 in FIG. 9(b) as a starting point to position P24. Note that in FIG. 9(b), the time at position P21 is indicated as t21, the time at position P22 as t22, the time at position P23 as t23, and the time at position P24 as t24.

[0094] The control unit CU calculates the amount of deviation of the focus ring FR from the reference position based on the position of the focus ring FR detected by the position detection sensors S11 and S12 and a predetermined reference position. Subsequently, the control unit CU controls the processing unit side transport device TR1 to place the focus ring FR on the mounting table 3 of the process module PM1 so as to correct the calculated amount of deviation. This allows the focus ring FR to be placed at a predetermined position on the mounting table 3 of the process module PM1 even if the position of the focus ring FR held by the pick 112 is deviated from the reference position.

[0095] The position of the focus ring FR held by the pick 112 can be calculated based on changes in the outputs of the position detection sensors S11 and S12 that occur when the inner peripheral edge of the focus ring FR passes through the position detection sensors S11 and S12. For example, as shown in FIG. 9A, when the focus ring FR is transported from position P21 to position P24, the position can be calculated based on the time T2 it takes for the focus ring FR to move from position P22 to position P23. Position P22 is the position where the sensor outputs of the position detection sensors S11 and S12 change from low (L) to high (H), and position P23 is the position where the sensor outputs of the position detection sensors S11 and S12 change from high (H) to low (L). Specifically, as shown in FIG. 9B, T2 can be calculated using time t22 at position P22 and time t23 at position P23 as T2 = t23 - t22. Although FIG. 9 shows a case where the position detection sensor S11 and the position detection sensor S12 are shielded from light by the focus ring FR at the same position, these positions may be different.

[0096] Furthermore, if the focus ring FR is damaged or dropped during transport, the waveform shown in Fig. 9 cannot be detected. In this case, it is determined that an abnormality has occurred in the transport of the focus ring, and the transport process is interrupted.

[0097] The reference position can be calculated based on, for example, the encoder positions of the rotation motor and extension motor of the first arm 111 of the processing unit side transport device TR1. Note that the method for calculating the reference position is not limited to this, and various existing methods can be used.

[0098] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and various modifications and variations are possible within the scope of the gist of the present invention as set forth in the claims.

[0099] In the above embodiment, the first cleaning step S30 and the second cleaning step S50 are described as being performed using plasma, but the present invention is not limited to this. For example, a non-plasma particle cleaning (NPPC) process may be used, which uses gas impact force, gas viscous force, and electromagnetic stress to remove particles from components inside the processing chamber and then discharge them from the processing chamber (see Japanese Patent Application Laid-Open No. 2005-101539). [Explanation of symbols]

[0100] 3. Mounting table 10 Processing Room 112 picks 113 Protrusion FR focus ring PM Process Module TM Transfer Module TR1 Processing unit side transport device TR2 transport unit side transport device W wafer

Claims

1. a first transfer module; a first transfer device provided inside the first transfer module; a process module connected to the first transfer module; a first load lock module connected to the first transfer module; a second load lock module connected to the first transfer module; a second transfer module connected to the first load lock module and the second load lock module, the second transfer module being connected to a container for storing unused rings; a second transfer device provided inside the second transfer module; A control unit; Equipped with The control unit controls the first conveying device, (a) transporting a used ring, which has been unloaded from the process module, toward the first load lock module without opening the process module to the atmosphere; The control unit controls the second conveying device, (b) carrying the unused ring housed in the container connected to the second transfer module into the second load lock module; The control unit controls the first conveying device, (c) after (b), carrying the unused ring carried out from the second load lock module into the process module without opening the process module to the atmosphere; The control unit controls the first conveying device, (d) before (a), unloading the substrate from the process module; Plasma treatment system.

2. The control unit controls the first conveying device, (e) after (c), loading the substrate into the process module; 10. The plasma processing system of claim 1.

3. a position detection sensor provided on a transport path of the unused ring transported by the first transport device at a position where the unused ring can be detected; the position detection sensor detects the position of the unused ring based on an output generated when the unused ring passes through the position detection sensor during transport of the unused ring from the first transport module to the process module.

3. The plasma processing system according to claim 1.

4. The used ring is stored in the container in which the unused ring is stored. The plasma processing system of claim 1 .

5. the first transport device and the second transport device are configured to be able to transport a substrate; The plasma processing system of claim 1 .

6. The container is a FOUP (Front Opening Unified Pod), The plasma processing system of claim 1 .

7. The second transport device is configured to be able to hold two substrates or two rings at a time. The plasma processing system of claim 1 .

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