JP2021061415A - Pick, transport device, and plasma processing system - Google Patents

Abstract

To provide a pick, a transport device, and a plasma processing system that can improve productivity.SOLUTION: In the plasma processing system, a pick 112 that holds a substrate and a focus ring FR has a plurality of protrusions 113 that contacts the focus ring at its upper surface to hold the outer edge of the substrate. The protrusions 113 are capable of holding the focus ring FR by contacting a lower surface of the focus ring FR at an upper surface 115 in the shape of a cone.SELECTED DRAWING: Figure 6

Description

The present invention relates to picks, transport devices and plasma processing systems.

A plasma processing apparatus is known in which a substrate is placed on a mounting table provided inside a processing chamber to perform plasma processing. In such a plasma processing apparatus, there are consumable parts that are gradually consumed by repeating the plasma processing (see, for example, Patent Document 1).

Examples of consumable parts include a focus ring provided around the substrate on the upper surface of the mounting table. The focus ring is scraped by exposure to plasma and needs to be replaced regularly.

Therefore, conventionally, the treatment chamber is opened to the atmosphere on a regular basis, and the operator manually replaces the focus ring.

Japanese Unexamined Patent Publication No. 2006-253541

However, in the method of opening the processing chamber to the atmosphere, it takes a long time to replace the focus ring, and the substrate cannot be processed in the processing chamber while the focus ring is being replaced, so that the productivity is lowered. ..

The present disclosure provides a technique capable of improving productivity.

The pick of one aspect of the present disclosure is a pick that holds the substrate and the focus ring, is a plurality of protrusions that hold the outer peripheral edge of the substrate, and has a plurality of protrusions that abut the focus ring on the upper surface.

According to the present disclosure, productivity can be improved.

Schematic configuration diagram showing a plasma processing system of one embodiment Schematic cross-sectional view showing the plasma processing apparatus of one embodiment Flow chart for explaining the focus ring replacement method of one embodiment The figure for demonstrating the processing unit side transfer apparatus of FIG. The figure which shows the state which the processing unit side transfer apparatus of FIG. 1 holds a wafer. The figure which shows the state which the processing unit side transfer device of FIG. 1 holds a focus ring. The figure for demonstrating the position detection sensor of FIG. The figure for demonstrating the method of correcting the position of a wafer. Diagram for explaining how to correct the position of the focus ring

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals to omit duplicate explanations.

In the focus ring replacement method of the embodiment of the present invention, the focus ring is carried out from the processing chamber by a transport device, the processing chamber is cleaned, and the focus ring is moved into the processing chamber by the transport device without opening the treatment chamber to the atmosphere. It is to be carried in. The focus ring is a member provided inside the processing chamber and placed so as to surround the periphery of the substrate on the upper surface of the mounting table on which the substrate is placed, and is for improving the uniformity of etching. is there.

The focus ring replacement method of the embodiment of the present invention can be applied to various plasma processing devices in which the focus ring is used.

(Plasma processing system)
First, the plasma processing system according to the embodiment of the present invention will be described. FIG. 1 is a schematic configuration diagram showing a plasma processing system of one embodiment.

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

The processing unit PU is a unit that performs predetermined processing such as film formation processing and etching processing on a substrate such as a semiconductor wafer (hereinafter referred to as “wafer W”). The processing unit PU includes process modules PM1 to PM6, a transfer module TM, and load lock modules LL1 and LL2. The number of process modules PM and load lock modules LL is not limited to the above.

The process modules PM1 to PM6 are connected to the periphery of the transfer module TM, and perform a predetermined process such as a film forming process and an etching process on the wafer W. The process modules PM1 to PM6 may perform the same type of processing or may perform different types of processing.

Inside the process modules PM1 to PM6, mounting tables 3 for mounting the wafer W are provided. Although not shown, the process modules PM1 to PM6 are provided with, for example, a gas introduction system for introducing purge gas, a gas introduction system for introducing processing gas, and an exhaust system capable of evacuating.

In the process modules PM1 to PM6, a predetermined process is performed on the wafer W based on a recipe or the like indicating a process step stored in advance in a storage unit or the like of the control unit CU. Further, in the process modules PM1 to PM6, the focus ring is replaced at a predetermined timing stored in the storage unit or the like of the control unit CU in advance. The details of the process module PM and the focus ring replacement method will be described later.

The transfer module TM is formed in a hexagonal shape in which a pair of opposite sides are longer than the other sides. Process modules PM3 and PM4 are connected to the two short sides on the tip side of the transfer module TM via gate valves G3 and G4, respectively. The load lock modules LL1 and LL2 are connected to the two short sides of the transfer module TM on the base end side via gate valves G7 and G8, respectively. Process modules PM1 and PM2 are connected to one long side of the transfer module TM via gate valves G1 and G2, respectively. Process modules PM5 and PM6 are connected to the other long side of the transfer module TM via gate valves G5 and G6, respectively.

The transfer module TM has a function of transporting (carrying out and carrying in) the wafer W and the focus ring 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 purge gas and an exhaust system capable of evacuating.

Inside the transfer module TM, a processing unit-side transfer device TR1 for transporting the wafer W and the focus ring between the process modules PM1 to PM6 and the load lock modules LL1 and LL2 is provided. The details of the processing unit side transfer device TR1 will be described later.

Position detection sensors S11 and S12 are provided on the transfer path of the wafer W and the focus ring that are transferred from the transfer module TM to the process module PM1 in the vicinity of the gate valve G1 of the transfer module TM. The position detection sensors S11 and S12 are arranged 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. As a result, the positions of the wafer W and the focus ring transported to the process module PM1 can be corrected. The details of the position detection sensors S11 and S12 will be described later.

Similarly, a position detection sensor is provided in the vicinity of the gate valves G2 to G6 of the transfer module TM on the transfer path of the wafer W and the focus ring transferred from the transfer module TM to the process modules PM2 to 6. ing. 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.

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 a function of temporarily holding the wafer W transported from the transport module LM and transporting the wafer W to the transfer module TM after adjusting the pressure. Further, the load lock modules LL1 and LL2 have a function of temporarily holding the wafer W transferred from the transfer module TM and transferring the wafer W to the transfer module LM after adjusting the pressure.

Inside the load lock modules LL1 and LL2, a delivery table on which the wafer W can be placed is provided. Further, although not shown, the load lock modules LL1 and LL2 are provided with an exhaust system capable of purging and exhausting particles such as residues.

In such a processing unit PU, the process modules PM1 to PM6 and the transfer module TM and the transfer module TM and the load lock modules LL1 and LL2 can be opened and closed airtightly, respectively. Further, the transfer module LM and the load lock modules LL1 and LL2 can be opened and closed airtightly, respectively.

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

The transport 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 transport module LM. FOUP can be mounted on each of the load ports LP1 to LP3. Note that FIG. 1 shows a case where the FOUP is mounted on all of the load ports LP1 to LP3. The FOUP is a container capable of accommodating, for example, 25 wafers W in multiple stages at equal pitches. The FOUP has a closed structure in which, for example, N _{2 gas is filled.} The FOUP is connected to the transport module LM via the opening / closing doors D1 to D3. The number of load port LPs is not limited to the above.

An aligner AU is provided on one short side of the transport module LM. The aligner AU has a rotary mounting table on which the wafer W is placed, and an optical sensor that optically detects the outer peripheral edge of the wafer W. The aligner AU detects, for example, the orientation flat, the notch, and the like of the wafer W to align the wafer W.

Inside the transport module LM, a transport unit-side transport device TR2 for transporting the wafer W and the focus ring between the load lock modules LL1, LL2, FOUP, and the aligner AU is provided. The transport unit-side transport device TR2 includes a transport arm that is rotatably attached to the base 231 by a swivel mechanism, and is slidable along the longitudinal direction of the transport module LM by a slide mechanism. The transport arm of the transport unit side transport device TR2 is, for example, as shown in FIG. 1, a double arm mechanism having a pair of articulated arms. The transport arm shown in FIG. 1 includes a first arm 211 and a second arm 221 which are vertically and contractably extendable articulated arms.

The slide mechanism of the transfer device TR2 on the transfer unit side includes, for example, a linear motor. Specifically, the guide rail 232 is provided inside the transport module LM along the longitudinal direction, and the base 231 to which the transport arm is attached is slidably provided along the guide rail 232. The base 231 and the guide rail 232 are provided with a linear motor mover and a stator, respectively, and a linear motor drive mechanism 233 for driving the linear motor is provided at the end of the guide rail 232. ing. A control unit CU is connected to the linear motor drive mechanism 233. As a result, the linear motor drive mechanism 233 is driven based on the control signal from the control unit CU, and the transfer unit side transfer device TR2 moves in the arrow direction along the guide rail 232 together with the base 231. The slide mechanism of the transport unit TR2 is not limited to the above, and may have other mechanisms.

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 hold two wafers W or two focus rings at a time. Can be done. Thereby, for example, when the wafer W and the focus ring are conveyed to the load lock modules LL1, LL2, FOUP, and the aligner AU, the wafer W and the focus ring can be conveyed so as to be exchanged. In addition, one wafer W and one focus ring may be held and conveyed at a time. Further, 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.

Further, the transport unit-side transport device TR2 includes a swing motor (not shown), a telescopic motor, and a lift motor for swinging, expanding / contracting, and raising / lowering the transport arm. Each motor is connected to the control unit CU and can control the transfer arm of the transfer unit side transfer device TR2 based on the control signal from the control unit CU.

The plasma processing system is provided with a control unit CU that controls each part of the plasma processing system, for example, 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. Has been done.

(Plasma processing equipment)
Next, the plasma processing apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view showing the plasma processing apparatus of 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 above-mentioned plasma processing system.

As shown in FIG. 2, the plasma processing apparatus has a processing chamber 10 having a substantially cylindrical shape. The inner wall surface of the treatment chamber 10 is formed of, for example, anodized aluminum. The processing chamber 10 is grounded.

The processing chamber 10 is provided with a gas shower head 2 for introducing the processing gas. The gas shower head 2 functions as an upper electrode. Inside the processing chamber 10, a mounting table 3 is provided so as to face the gas shower head 2. The mounting table 3 functions as a lower electrode.

On the lower surface side of the gas shower head 2 (upper electrode), a plurality of gas discharge ports 22 communicating with each other via the gas supply path 21 and the buffer chamber 21a are formed. The processing gas is discharged toward the wafer W mounted on the mounting table 3 by the plurality of gas discharge ports 22. The base end side of the gas supply path 21 is connected to the gas introduction system 23.

The gas introduction system 23 has a supply source of the processing gas used for the film forming process on the wafer W and a supply source of the processing gas used for the etching process on the wafer W. Further, the gas introduction system 23 has a processing chamber 10 as a supply source of the processing gas used for the cleaning treatment, and the treatment chamber 10 as a supply source of the processing gas used for the seasoning treatment. The gas introduction system 23 has a supply control device such as a valve and a flow rate adjusting unit, and can supply a processing gas having a predetermined flow rate into the processing chamber 10.

A high frequency power supply unit 26 for supplying high frequency power via the matching device 25 is connected to the upper electrode. The upper electrode is insulated from the side wall portion of the processing chamber 10 by the insulating member 27.

The mounting table 3 has a main body portion 30 and an electrostatic chuck 31.

The main body 30 is formed of a conductive member such as aluminum. Inside the main body 30, a refrigerant flow path (not shown) that functions as a temperature control mechanism is provided. By adjusting the temperature of the refrigerant supplied to the refrigerant flow path, the temperature of the wafer W held by the electrostatic chuck 31 is controlled.

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

The electrostatic chuck 31 has an electrode 35 interposed between the insulating materials. The electrode 35 is provided so as to extend not only to the lower side of the substrate mounting surface 33 but also to the lower side of the focus ring mounting surface 34 so that both the wafer W and the focus ring FR can be attracted to the electrode 35.

A predetermined DC voltage is applied to the electrostatic chuck 31 from the DC power supply 37 connected to the electrode 35 via the switch 36. As a result, the wafer W and the focus ring FR are electrostatically attracted to the electrostatic chuck 31. 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, and when the wafer W is mounted, the edge portion of the wafer W is stretched from the substrate mounting portion 32. Try to put it out.

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

The heat transfer gas supply unit 38 is placed on the first heat transfer gas supply unit 38a that supplies the first heat transfer gas to the back surface of the wafer W mounted on the substrate mounting surface 33 and on the focus ring mounting surface 34. A second heat transfer gas supply unit 38b for supplying the second heat transfer gas is provided on the back surface of the focus ring FR.

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 peripheral portion is formed higher than the inner peripheral portion. Further, the inner peripheral portion of the focus ring FR is formed so as to bite into the lower side of the outer peripheral portion of the wafer W protruding outward from the mounting table 3. That is, the inner diameter of the focus ring FR is formed to be smaller than the outer diameter of the wafer W. As a result, the electrostatic chuck 31 is protected from plasma when the wafer W is etched.

A high-frequency power supply unit 40 that applies power for bias is connected to the mounting table 3 via a matching unit 39. Further, inside the mounting table 3, an elevating pin (not shown) capable of delivering the wafer W and the focus ring FR to the processing unit side transport device TR1 shown in FIG. 1 is provided. When the focus ring FR is delivered by the processing unit side transfer device TR1, the elevating pin is raised to separate the focus ring FR from the mounting table 3.

An opening 13 having a gate valve G1 that can be opened and closed is formed on the side wall of the processing chamber 10. The wafer W and the focus ring FR are conveyed through the opening 13.

A depot shield 41 is detachably provided on the inner wall of the processing chamber 10 along the inner wall. The depot shield 41 is also provided on the outer periphery of the mounting table 3. Deposition shield 41 serves to prevent the reaction products produced by the etching is deposited on the inner wall surface of the processing chamber 10 is formed by coating a ceramic such as Y ₂ O _3, for example, aluminum.

A baffle plate 42 having a large number of exhaust holes is provided around the mounting table 3 in order to uniformly exhaust the inside of the processing chamber 10. The baffle plate 42 is formed, for example, by coating a ceramic such as Y ₂ O ₃ in aluminum. A vacuum pump 12 such as a turbo molecular pump or a dry pump is connected below the baffle plate 42 via an exhaust pipe 11.

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 includes steps for, for example, supplying each gas from the gas introduction system 23 and controlling the power supply from the high frequency power supply units 26 and 40 for performing the film forming process and the etching process on the wafer W by the plasma processing apparatus. (Order) A group is formed. The program is stored in a storage medium such as a hard disk, a compact disk, or a memory card, and is installed in the computer from the storage medium.

(Focus ring replacement method)
Next, the focus ring replacement method according to the embodiment of the present invention will be described with reference to FIG. FIG. 3 is a flowchart for explaining the focus ring replacement method of one embodiment.

In the following, a case where the focus ring FR mounted on the mounting table 3 of the process module PM1 described above is replaced will be described as an example. Specifically, a case where the focus ring used in the process module PM1 is housed in the FOUP and replaced with an unused focus ring previously housed in the FOUP will be described. The focus ring FR mounted on the mounting table 3 of the process modules PM2 to PM6 other than the process module PM1 can also be replaced by the same method. Further, the focus ring replacement method of the embodiment of the present invention is performed by controlling each part of the plasma processing system by the control unit CU.

As shown in FIG. 3, the focus ring replacement method of one embodiment includes a wear degree determination step S10, a replaceability determination step S20, a first cleaning step S30, a carry-out step S40, and a second cleaning step. It has S50, a carry-in step S60, and a seasoning step S70. Each step will be described below.

The wear degree determination step S10 is a step of determining whether or not the focus ring FR mounted on the mounting table 3 of the process module PM1 needs to be replaced. In the consumption degree determination step S10, the control unit CU determines whether or not 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 or not the focus ring FR needs to be replaced based on, for example, the RF integration time, the RF integration power, and the integration value of the specific step of the recipe. The RF integration time is an integrated value of the time during which high-frequency power is supplied in the process module PM1 during a predetermined plasma process. The RF integrated power is an integrated value of high-frequency power supplied in the process module PM1 during a predetermined plasma process. The integrated value of the specific step of the recipe is an integrated value of the time when high frequency power is supplied or an integrated value of high frequency power in the step of cutting the focus ring FR among the processing steps performed in the process module PM1. The integrated values of the RF integrated time, the RF integrated power, and the specific steps of the recipe are calculated starting from the time when the focus ring FR is replaced, such as when the device is introduced or when maintenance is performed. is there.

When determining whether or not the focus ring FR needs to be replaced based on the RF integration time, the control unit CU determines that the focus ring FR needs to be replaced when the RF integration time reaches the threshold value. .. On the other hand, the control unit CU determines that it is not necessary to replace the focus ring FR when the RF integration time has not reached the threshold value. The threshold value is a value determined by a preliminary experiment or the like according to the type of the material of the focus ring FR.

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 when the RF integrated power reaches the threshold value. .. On the other hand, the control unit CU determines that it is not necessary to replace the focus ring FR when the RF integrated power does not reach the threshold value. The threshold value is a value determined by a preliminary experiment or the like according to the type of the material of the focus ring FR.

When determining whether or not the focus ring FR needs to be replaced based on the integrated value of the specific step of the recipe, the control unit CU determines when the RF integrated time or the RF integrated power in the specific step reaches the threshold value. It is determined that the focus ring FR needs to be replaced. On the other hand, the control unit CU determines that it is not necessary to replace the focus ring FR when the RF integration time or the RF integration power in the specific step has not reached the threshold value. When determining whether or not the focus ring FR needs to be replaced based on the integrated value of a specific step of the recipe, the focus ring FR is replaced based on the step in which high frequency power is applied and the focus ring FR is scraped. The timing can be calculated. Therefore, it is possible to calculate the timing for exchanging the focus ring FR with particularly high accuracy. The threshold value is a value determined by a preliminary experiment or the like according to the type of the material of the focus ring FR.

When it is determined in the wear degree 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 the replaceability determination step S20. When it is determined in the wear degree 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 the wear degree determination step S10.

The exchangeability determination step S20 is a step of determining whether or not the state of the plasma processing system is a state in which the focus ring FR can be exchanged. In the exchangeability determination step S20, the control unit CU determines whether or not the state of the plasma processing system is a state in which the focus ring FR can be exchanged. Specifically, the control unit CU determines that the focus ring FR can be replaced, for example, when the wafer W is not processed in the process module PM1 that replaces the focus ring FR. On the other hand, the control unit CU determines that the focus ring FR cannot be replaced when the wafer W is processed in the process module PM1. Further, the control unit CU can replace the focus ring FR, for example, when the processing of the wafer W of the same lot as the wafer W being processed in the process module PM1 for replacing the focus ring FR is completed. May be determined. In this case, the control unit CU determines that the focus ring FR cannot be replaced until the processing of the wafer W of the same lot as the wafer W being processed in the process module PM1 is completed.

When it is determined in the replaceability determination step S20 that the state of the plasma processing system is a state in which the focus ring FR can be replaced, the control unit CU performs the first cleaning step S30. When it is determined in the replaceability determination step S20 that the state of the plasma processing system is a state in which the focus ring FR cannot be replaced, the control unit CU repeats the replaceability determination step S20.

The first cleaning step S30 is a step of performing a cleaning process of the process module PM1. In the first cleaning step S30, the control unit CU performs a cleaning process of the process module PM1 by controlling the gas introduction system, the exhaust system, the power introduction system, and the like. The cleaning process is a process of removing the deposits in the process module PM1 generated by the plasma process by plasma of the 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 the deposits in the processing chamber 10 from being rolled up when the focus ring FR is carried out from the mounting table 3 in the carry-out step S40. As the processing gas, for example, oxygen (O ₂ ) gas, fluorocarbon (CF) gas, nitrogen (N ₂ ) gas, argon (Ar) gas, He gas, or a mixed gas of two or more of these can be used. Can be used. Further, when cleaning the process module PM1, depending on the processing conditions, in order to protect the electrostatic chuck of the mounting table 3, the cleaning process is performed with the wafer W such as a dummy wafer mounted on the upper surface of the electrostatic chuck. You may. If the deposit does not roll up, such as when there is no deposit in the processing chamber 10, the first cleaning step S30 may not be performed. When the focus ring FR is attracted to the mounting table 3 by the electrostatic chuck, the static electricity elimination process is performed by the next carry-out step S40.

The carry-out step S40 is a step of carrying out the focus ring FR from the process module PM1 without opening the process module PM1 to the atmosphere. In the carry-out step S40, the control unit CU controls each part of the plasma processing system so as to carry out the focus ring FR from the inside of the process module PM1 without opening the process module PM1 to the atmosphere. Specifically, the gate valve G1 is opened, and the focus ring FR mounted on the mounting table 3 inside the process module PM1 is carried out from the process module PM1 by the processing unit side transfer device TR1. Subsequently, the gate valve G8 is opened, and the focus ring FR carried out from the process module PM1 is placed on the delivery table of the load lock module LL2 by the processing unit side transfer device TR1. Subsequently, the gate valve G8 is closed, the pressure in the load lock module LL2 is adjusted, the gate valve G10 is opened, and the focus ring FR mounted on the delivery table is conveyed to the transfer module TM by the transfer unit side transfer device TR2. .. Subsequently, the opening / closing door D3 is opened, and the focus ring FR is housed in the FOUP mounted on the load port LP3 by the transport unit side transport device TR2.

The second cleaning step S50 is a step of cleaning the surface (focus ring mounting surface 34) on which the focus ring FR of the mounting table 3 of the process module PM1 is mounted. In the second cleaning step S50, the control unit CU controls the gas introduction system, the exhaust system, the power introduction system, and the like to clean the surface on which the focus ring FR of the mounting table 3 of the process module PM1 is mounted. I do. The cleaning process in the second cleaning step S50 can be performed, for example, in the same manner as in the first cleaning step S30. That is, as the processing gas, for example, O ₂ gas, CF gas, N ₂ gas, Ar gas, He gas, or a mixed gas of two or more of these can be used. Further, when performing the cleaning process of the process module PM1, the cleaning process is performed with the wafer W such as a dummy wafer mounted on the upper surface of the electrostatic chuck in order to protect the electrostatic chuck of the mounting table 3 depending on the processing conditions. You may.

The carry-in step S60 is a step in which the focus ring FR is carried into the process module PM1 and placed on the mounting table 3 without opening the process module PM1 to the atmosphere. In the carry-in step S60, the control unit CU controls each part of the plasma processing system so as to carry 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 unused focus ring FR housed in the FOUP mounted on the load port LP3 is carried out by the transport unit side transport device TR2. Subsequently, the gate valve G9 is opened, and the unused focus ring FR is placed on the delivery table of the load lock module LL1 by the transfer unit side transfer device TR2. Subsequently, the gate valve G7 and the gate valve G1 are opened, and the unused focus ring FR mounted on the delivery table of the load lock module LL1 is carried out by the processing unit side transfer device TR1 and carried into the process module PM1. It is placed on the mounting table 3.

The seasoning step S70 is a step of performing the seasoning process of the process module PM1. In the seasoning step S70, the control unit CU performs the seasoning process of the process module PM1 by controlling the gas introduction system, the exhaust system, the power introduction system, and the like. The seasoning treatment is a treatment for stabilizing the temperature and the state of deposits in the process module PM1 by performing a predetermined plasma treatment. Further, in the seasoning step S70, after the seasoning process of the process module PM1, the quality control wafer may be carried into the process module PM1 and the quality control wafer may be subjected to a predetermined process. This makes it possible to confirm whether or not the state of the process module PM1 is normal.

By the above steps, the focus ring FR can be replaced.

As described above, in the focus ring replacement method of the embodiment of the present invention, the focus ring FR is carried out from the processing chamber 10 by the processing unit side transport device TR1 and processed without opening the processing chamber 10 to the atmosphere. The inside of the chamber 10 is cleaned, and the focus ring FR is carried into the processing chamber 10 by the processing unit side transfer device TR1. This eliminates the need for the operator to manually replace the focus ring FR. Therefore, the time required for replacing the focus ring FR can be shortened, and the productivity is improved. Further, by cleaning the focus ring mounting surface 34 before carrying in the focus ring FR, it is possible to suppress the presence of deposits between the focus ring FR and the focus ring mounting surface 34. As a result, the temperature controllability of the focus ring FR can be maintained well by improving the contact between the two.

(Transfer device on the processing unit side)
Next, an example of the processing unit side transport device TR1 will be described with reference to FIG. FIG. 4 is a diagram for explaining the processing unit side transfer device of FIG.

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

Next, an example of the swivel mechanism of the processing unit side transport device TR1 will be described. As shown in FIG. 4, for example, the transport arms (first arm 111, second arm 121) of the processing unit side transport device TR1 are provided on the base 131 so as to be swivelable in the direction of the θ axis which is the swivel axis. It is attached via the rotating plate 135. The rotating plate 135 is driven by, for example, a θ-axis motor 136 provided on the base 131. Thereby, by driving and controlling the θ-axis motor 136, it is possible to control the turning drive of the transport arm of the processing unit side transport device TR1.

The first arm 111 and the second arm 121, which are the transfer arms of the processing unit side transfer device TR1, are provided with picks 112 and 122 at their tips, respectively, and hold two wafers W or two focus ring FRs at a time. You can do it. Thereby, for example, when the wafer W or the focus ring FR is conveyed to the process modules PM1 to PM6 and the load lock modules LL1 and LL2, the wafer W or the focus ring FR can be conveyed so as to be exchanged. 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.

Further, the processing unit side transfer device TR1 has an expansion / contraction motor (not shown) for expanding / contracting the transfer arm. The expansion / contraction motor is attached to the lower side of the θ-axis motor 136, for example, and can be controlled independently of the θ-axis motor 136. In addition to the above, as the motor for driving the processing unit side transport device TR1, a lifting motor (not shown) for raising and lowering the transport arm may be provided.

The θ-axis motor 136, the Y-axis motor 133, etc. for driving the processing unit-side transfer device TR1 are connected to the control unit CU, respectively, and are driven and controlled based on a command from the control unit CU. It has become.

As shown in FIG. 1, for example, a flexible arm 137 for passing the wiring of the θ-axis motor 136 and the like is connected to the base 131 of the processing unit side transport device TR1. The flexible arm 137 is composed of, for example, an arm mechanism formed in a tubular shape. The flexible arm 137 is airtightly connected, and the inside thereof communicates with the atmosphere through 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 in an atmospheric pressure state, so that damage to the wiring can be prevented.

As described above, according to the processing unit side transfer device TR1, the transfer arm can be expanded and contracted while being slid-driven along the guide rails 132a and 132b. As a result, the wafer W and the focus ring FR can be conveyed between the process modules PM1 to PM6 and the load lock modules LL1 and LL2.

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. 5A is a side view of the pick 112 holding the wafer W, and FIG. 5B is a top view of the pick 112 holding the wafer W. FIG. 6 is a diagram showing a state in which the processing unit-side transport device of FIG. 1 holds the focus ring. FIG. 6A is a side view of the pick 112 holding the focus ring FR, and FIG. 6B is a top view of the pick 112 holding the focus ring FR. Although the pick 112 will be described as an example in FIGS. 5 and 6, the same can be applied to the pick 122.

As shown in FIG. 5, the pick 112 is formed with a plurality of (for example, three) protrusions 113 for holding the outer peripheral edge portion of the wafer W. The protrusion 113 has, for example, a truncated cone shape, is arranged along the outer peripheral edge of the wafer W, and the protrusion 113 abuts on the outer peripheral edge of the wafer W at the truncated cone-shaped tapered portion 114, thereby causing the pick 112. The position shift of the wafer W with respect to the above is prevented. The protrusion 113 is formed of, for example, an elastomer.

Further, as shown in FIG. 6, the protrusion 113 can hold the focus ring FR by contacting the lower surface of the focus ring FR on the truncated cone-shaped upper surface 115. This is because, as described above, the inner diameter of the focus ring FR is formed to be 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 by one pick 112.

As described above, the pick 112 holds the wafer W at the tapered portion 114 of the protruding portion 113 and holds the focus ring FR at the upper surface 115 of the protruding portion 113, so that the length of the pick 112 is not increased. , The focus ring FR can be held. This makes it possible to prevent the tip of the pick 112 from coming into contact with another portion (for example, the inner wall surface of the FOUP) when the wafer W or the focus ring FR is conveyed by the pick 112. In FIGS. 5 and 6, the case where the number of protrusions 113 is three has been described as an example, but the number of protrusions 113 is not limited to this.

Further, when the processing unit side transport device TR1 turns while holding the focus ring FR, it is preferable that the processing unit side transport device TR1 turns so that the turning radius is minimized. As a result, it is possible to prevent the focus ring FR held by the pick 112 from coming into contact with other parts. Further, when the two picks 112 and 122 rotate in substantially 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 are held. It is possible to prevent contact with the ring FR.

(Position detection sensor)
Next, an example of the position detection sensor will be described with reference to FIG. FIG. 7 is a diagram for explaining the position detection sensor of FIG. 1, and shows a part of a cross section cut along the alternate long and short dash line 1A-1B in FIG.

As shown in FIG. 7, the position detection sensor S11 has a light emitting unit 310 and a light receiving unit 320. The light emitting unit 310 is provided on the upper wall 330 of the transfer module TM, and the light receiving unit 320 is provided on the lower wall 340 of the transfer module TM. The light emitting unit 310 irradiates the laser beam L toward the light receiving unit 320. The light receiving unit 320 detects the presence or absence of light reception of the laser beam L emitted from the light projecting unit 310. Although the light emitting unit 310 and the light receiving unit 320 of the position detection sensor S11 are illustrated in FIG. 7, the position detection sensor S12 also has a light emitting unit and a light receiving unit like the position detection sensor S11. There is. As a result, the laser beam L emitted from the light emitting unit 310 to the light receiving unit 320 of the position detection sensor S11 is blocked by the wafer W or the focus ring FR conveyed from the transfer module TM to the process module PM1 for a predetermined time. Further, the laser beam L emitted from the light emitting portion to the light receiving portion of the position detection sensor S12 is blocked by the wafer W or the focus ring FR conveyed from the transfer module TM to the process module PM1 for a predetermined time.

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

In the method of correcting the positions of the wafer W and the focus ring FR according to the embodiment of the present invention, the control unit CU performs the position correction of the wafer W and the position correction of the focus ring FR by the same position detection sensor. Hereinafter, a specific description will be given.

First, a case where the wafer W is transferred from the transfer module TM to the process module PM1 will be described with reference to FIG. FIG. 8 is a diagram for explaining a method of correcting the position of the wafer. FIG. 8A shows the relationship between the position of the wafer W and the position of the position detection sensor. FIG. 8B shows changes in the sensor outputs of the position detection sensors S11 and S12 when the wafer W is conveyed from the position P11 in FIG. 8A to the position P14. In FIG. 8B, the time at the position P11 is shown by t11, the time at the position P12 is shown by t12, the time at the position P13 is shown by t13, and the time at the position P14 is shown by t14.

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 the predetermined reference position. Subsequently, the control unit CU mounts the wafer W on the mounting table 3 of the process module PM1 so as to correct the calculated deviation amount by the processing unit side transport device TR1. As a result, even if the position of the wafer W held by the pick 112 deviates from the reference position, the wafer W can be placed at a predetermined position on the mounting table 3 of the process module PM1.

The position of the wafer W held by the pick 112 can be calculated based on the change in the sensor output of the position detection sensors S11 and S12 caused by the outer peripheral edge of the wafer W passing through the position detection sensors S11 and S12. .. For example, as shown in FIG. 8A, when the wafer W is conveyed from the position P11 to the position P14, the position detection sensors S11 and S12 are shielded by the wafer W based on the time T1 from the position P12 to the position P13. Can be calculated. Specifically, as shown in FIG. 8B, it can be calculated by T1 = t13-t12 using the time t12 at the position P12 and the time t13 at the position P13. Note that FIG. 8 shows a case where the position when the position detection sensor S11 is shielded from light by the wafer W and the position when the position detection sensor S12 is shielded from light are the same, but these positions may be different. Good.

The reference position can be calculated based on, for example, the encoder positions of the swing motor and the expansion / contraction motor of the first arm 111 of the processing unit side transfer device TR1. The method for calculating the reference position is not limited to this, and various existing methods can be used.

Next, a case where the focus ring FR is conveyed from the transfer module TM to the process module PM1 will be described with reference to FIG. FIG. 9 is a diagram for explaining a method of correcting the position of the focus ring. FIG. 9A shows the relationship between the position of the focus ring FR and the position of the position detection sensor. FIG. 9B shows changes in the sensor outputs of the position detection sensors S11 and S12 when the focus ring FR conveys the focus ring FR from the position P21 in FIG. 9B to the position P24. In FIG. 9B, the time at the position P21 is shown by t21, the time at the position P22 is shown by t22, the time at the position P23 is shown by t23, and the time at the position P24 is shown by t24.

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 the predetermined reference position. Subsequently, the control unit CU mounts the focus ring FR on the mounting table 3 of the process module PM1 so as to correct the calculated deviation amount by the processing unit side transport device TR1. As a result, even if the position of the focus ring FR held by the pick 112 deviates from the reference position, the focus ring FR can be placed at a predetermined position on the mounting table 3 of the process module PM1.

The position of the focus ring FR held by the pick 112 can be calculated based on the change in the output of the position detection sensors S11 and S12 caused by the inner peripheral edge of the focus ring FR passing through the position detection sensors S11 and S12. it can. For example, as shown in FIG. 9A, when the focus ring FR is conveyed from the position P21 to the position P24, it can be calculated based on the time T2 at which the focus ring FR moves from the position P22 to the position P23. The position P22 is a position where the sensor outputs of the position detection sensors S11 and S12 change from a low (L) level to a high (H) level, and the position P23 is a position where the sensor outputs of the position detection sensors S11 and S12 are high (H). This is the position where the level changes from the low (L) level. Specifically, as shown in FIG. 9B, it can be calculated by T2 = t23-t22 using the time t22 at the position P22 and the time t23 at the position P23. Note that FIG. 9 shows a case where the position where the position detection sensor S11 is shielded from light by the focus ring FR and the position where the position detection sensor S12 is shielded from light are the same, but these positions may be different.

Further, if the focus ring FR is damaged or dropped during transportation, the waveform shown in FIG. 9 cannot be detected. In this case, it is determined that the focus ring transport is abnormal, and the transport process is interrupted.

The reference position can be calculated based on, for example, the encoder positions of the swing motor and the expansion / contraction motor of the first arm 111 of the processing unit side transfer device TR1. The method for calculating the reference position is not limited to this, and various existing methods can be used.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the specific embodiment, and various modifications are made within the scope of the gist of the present invention described in the claims.・ Can be changed.

In the above embodiment, the case where the cleaning process using plasma is performed in the first cleaning step S30 and the second cleaning step S50 has been described as an example, but the present invention is not limited to this. For example, in a process using NPPC (Non Plasma Particle Cleaning) that separates particles from the components inside the treatment chamber using gas impact force, gas viscous force, and electromagnetic stress without using plasma and discharges them from the inside of the treatment chamber. It may be present (Japanese Patent Laid-Open No. 2005-101039).

3 Mounting stand 10 Processing chamber 112 Pick 113 Protrusion FR Focus ring PM Process module TM Transfer module TR1 Processing unit side transfer device TR2 Transfer unit side transfer device W Wafer

Claims (11)

A pick that holds the board and focus ring
A plurality of protrusions that hold the outer peripheral edge of the substrate, and have a plurality of protrusions that come into contact with the focus ring on the upper surface.
pick. The protrusion has a truncated cone shape, the substrate is held by the tapered portion of the truncated cone shape, and the focus ring is abutted on the upper surface of the truncated cone shape.
The pick according to claim 1. The protrusion is made of an elastomer.
The pick according to claim 1 or 2. Provided inside a evacuable module,
The pick according to any one of claims 1 to 3. A transport device that transports a substrate and a focus ring.
A plurality of protrusions that hold the outer peripheral edge of the substrate, and have a plurality of protrusions that come into contact with the focus ring on the upper surface.
Transport device. The protrusion has a truncated cone shape, the substrate is held by the tapered portion of the truncated cone shape, and the focus ring is abutted on the upper surface of the truncated cone shape.
The transport device according to claim 5. The protrusion is made of an elastomer.
The transport device according to claim 5 or 6. Provided inside a evacuable module,
The transport device according to any one of claims 5 to 7. Process module and
The transfer module to which the process module is connected and
A first load lock module and a second load lock module connected to the transfer module,
A transport module connected to the first load lock module and the second load lock module, and
The load port connected to the transport module and
The transport device according to any one of claims 5 to 8.
With
The transfer device is provided inside the transfer module, and transfers the focus ring between the process module, the first load lock module, and the second load lock module.
Plasma processing system. The transport device transports the used focus ring from the process module to the second load lock module without opening the process module to the atmosphere, and then transports the used focus ring from the process module to the second load lock module, and then the first load without opening the process module to the atmosphere. Transporting an unused focus ring from the lock module to the process module,
The plasma processing system according to claim 9. A pick that holds the board and focus ring
It comprises a plurality of protrusions having a surface that comes into contact with the focus ring, the surface being arranged outside the outer edge of the substrate held by the pick.
pick.

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