JP2007266261A - Conveyance pick, conveyer device, substrate processing apparatus and cleaning method of the conveyance pick - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide such a method which prevents a misregistration from occurring on a board held by a conveyance pick of a conveyer device, and effectively cleans particles adhered to an abutment member of the conveyance pick. <P>SOLUTION: A pick 17 of a wafer conveyer device 16 is moved beneath an ion generator 19, and negative charged particles (minus ions) are supplied from the ion generator 19 to the pick 17 to charge an abutment member 17a of the pick 17 to a negative compulsorily. Since the particles adhered to a surface of the abutment member 17a of the pick 17 are charged to a negative, the particles are separated from the abutment member 17a by a repulsion force of static electricity. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a transport pick used for transporting a substrate such as a semiconductor substrate, a transport apparatus and a substrate processing apparatus provided with the transport pick, and a transport pick cleaning method.

  In a substrate processing apparatus that performs processing such as etching on a substrate such as a semiconductor wafer, the substrate is transferred to the processing chamber, and therefore the substrate is held at the tip of a transfer arm that can be expanded, contracted, swung, and raised and lowered in any direction. A transport device (a transport robot) having a pick is used. A contact member made of an elastomer or the like is provided at a plurality of locations on the wafer holding surface of the transfer pick, and the contact member supports the substrate by contacting the substrate.

  The reason why the elastomer is used as the material of the contact member of the transport pick is to prevent the positional deviation of the substrate held by the transport pick using its adhesive force. However, if particles or deposits from the processed substrate adhere to the contact member while the substrate is repeatedly transported, the adhesive strength of the elastomer gradually decreases. As a result, misalignment of the substrate is likely to occur on the transport pick, leading to a decrease in transport accuracy and causing product defects. In the worst case, the substrate may be dropped during transport. Concerned. Further, if the substrate is transported in a state where particles are attached to the contact member of the transport pick that contacts the back surface of the substrate, the particles move to the back surface of the substrate and cause particle contamination of the substrate.

  For this reason, conventionally, an operator regularly cleans the contact member of the transport pick. However, since the manual cleaning requires a corresponding work time, it is necessary to stop the operation of the substrate processing apparatus during that time. Therefore, the cleaning cannot be performed frequently, and if the adhesive force of the transport pick decreases during that time, the substrate is displaced and the above-described problems occur.

In order to avoid particle contamination on the semiconductor substrate, the particle charging device charges the particles in the room, while the electric field forming device is used to form an electric field having the same polarity as the charged polarity of the particles on a member such as a transfer arm. A method for preventing adhesion of particles to a semiconductor substrate has been proposed (for example, Patent Document 1).
Japanese Patent Laying-Open No. 2005-116823 (for example, paragraph 0057)

  The method described in Patent Document 1 is a technique for preventing the adhesion of particles to a semiconductor substrate by forming an electric field that gives a repulsive force to particles around a member such as a transfer arm. No consideration is given to preventing the displacement of the substrate on the transport pick by removing (cleaning) the particles adhering to the substrate.

  The present invention has been made in view of the above circumstances, and its purpose is to prevent particles adhering to the contact member of the transport pick in order to prevent displacement of the substrate held by the transport pick of the transport device. The object is to provide an effective cleaning method.

In order to solve the above problems, a first aspect of the present invention is a transport pick that is attached to the tip of a transport arm and holds a substrate on a substrate holding surface in a transport device that transports a substrate,
A plurality of abutting members that project from the substrate holding surface and abut against the substrate;
A voltage application device for charging the contact member;
And a transport pick having a self-cleaning function for removing particles adhering to the contact member by a repulsive force of electric charges.

In the first aspect, the transport pick has a conductive member and an insulating member covering the periphery thereof,
It is preferable that the voltage application device is electrically connected to the conductive member and applies a positive or negative voltage to the conductive member.

  According to a second aspect of the present invention, there is provided a transport apparatus including the transport pick according to the first aspect.

According to a third aspect of the present invention, there is provided a substrate processing apparatus comprising: a processing chamber that performs a predetermined process on a substrate; and a transfer chamber in which a transfer device that transfers the substrate to the processing chamber is provided.
The transfer apparatus provides a substrate processing apparatus including the transfer pick according to the first aspect.

According to a fourth aspect of the present invention, there is provided a vacuum processing chamber for performing a predetermined process on a substrate, a transfer chamber provided with a transfer device for transferring a substrate to the vacuum processing chamber, the vacuum processing chamber, and the transfer chamber. A substrate processing apparatus provided with a vacuum preliminary chamber disposed between
The transfer device includes a transfer arm, and a transfer pick attached to the tip of the transfer arm and having a plurality of abutting members protruding from a substrate holding surface that holds the substrate.
Provided is a substrate processing apparatus including a charging device that supplies charged particles to the contact member and forcibly charges the contact member.

In the fourth aspect, it is preferable that the charging device applies a voltage so that the contact member is charged with the same polarity as the particles attached thereto.
The charging device may be provided in the transfer chamber. In this case, the transfer chamber includes an airflow forming device that forms a forced airflow in the transfer chamber, and an exhaust that exhausts the transfer chamber. It is preferable that the charging device is provided at a position downstream of the substrate transfer position by the transfer device in the flow direction of the airflow.

In the fourth aspect, the charging device may be provided in a cleaning chamber provided adjacent to the transfer chamber. In this case, the cleaning chamber is forcibly provided in the cleaning chamber. It is preferable that an airflow forming device that forms an airflow and an exhaust device that exhausts the cleaning chamber are provided.
The charging device may be provided in the vacuum preliminary chamber.

  According to a fifth aspect of the present invention, there is provided a substrate holding surface for holding a substrate, a plurality of substrate holding surfaces which are attached to a tip of a transfer arm for transferring a substrate in a substrate processing apparatus, and a plurality of the substrate holding surfaces which protrude from the substrate holding surface and come into contact with the substrate. The positive and negative voltages are alternately applied by the voltage application device to the transport pick provided with the contact member and the voltage application device for charging the contact member, thereby charging the contact member. There is provided a cleaning method for a transport pick including a cleaning step of repeatedly and forcibly charging so that the polarity is alternately switched between positive and negative, and removing particles adhering to the contact member by a repulsive force of electric charges.

  According to a sixth aspect of the present invention, there are provided a substrate holding surface for holding a substrate, a plurality of substrate holding surfaces which are attached to a tip of a transfer arm for transferring a substrate in the substrate processing apparatus, and a plurality of the substrate holding surfaces projecting from the substrate holding surface. A charging pick that supplies charged particles to the abutting member is repeatedly and forcibly charged so that the charging polarity of the abutting member is alternately switched between positive and negative. There is provided a cleaning method for a transport pick, which includes a cleaning step of removing particles adhering to the contact member due to the repulsive force.

In the fifth aspect or the sixth aspect, it is preferable that the cleaning step is performed during an idle time of a transfer apparatus in the substrate processing apparatus.
Further, it is preferable that an air flow is generated by an air flow forming device in the room where the transport pick is arranged during the cleaning process.
The substrate processing apparatus further includes: a vacuum processing chamber that performs a predetermined process on the substrate; a transfer chamber in which the transfer device that transfers the substrate to the vacuum processing chamber is disposed; the vacuum processing chamber and the transfer chamber It is preferable that the cleaning step is performed in the transfer chamber or the vacuum reserve chamber.

  In the fifth aspect or the sixth aspect, it is preferable that the method further includes a step of adjusting a charged state of the contact member after the cleaning.

  According to a seventh aspect of the present invention, there is provided a control program that operates on a computer and controls the substrate processing apparatus so that, when executed, the transport pick cleaning method according to the fifth aspect or the sixth aspect is performed. provide.

An eighth aspect of the present invention is a computer-readable storage medium storing a control program that runs on a computer,
The control program provides a computer-readable storage medium that controls the substrate processing apparatus so that the transport pick cleaning method according to the fifth aspect or the sixth aspect is performed at the time of execution.

  According to the present invention, it is possible to easily and in a short time perform cleaning of a transport pick that has been conventionally performed manually. Accordingly, the contact member of the transport pick can be kept clean at all times, and it is possible to prevent a situation where particles adhere to the contact member and the position of the substrate shifts or the substrate falls during the transport. . As a result, it is possible to reduce product defects due to a decrease in conveyance accuracy and to provide a highly reliable semiconductor device.

Further, by cleaning the transport pick and using it in a clean state, it is possible to reduce particle contamination on the substrate.
Furthermore, since it is possible to clean the transport pick in a short time, for example, by performing cleaning while the transport device is in a standby state, the downtime of the substrate processing apparatus can be reduced, and the substrate processing efficiency can be improved. Can do.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a horizontal sectional view schematically showing a plasma processing apparatus which is an embodiment of a substrate processing apparatus according to the present invention. The plasma processing apparatus 1 performs processing such as etching on a semiconductor wafer (hereinafter simply referred to as “wafer”) W as a substrate to be processed under a predetermined vacuum.

  The plasma processing apparatus 1 includes two processing units 2 and 3, and each processing unit 2 and 3 is configured to be able to perform an etching process on the wafer W independently. Load lock chambers 6 and 7 are connected to the respective processing units 2 and 3 through gate valves G1. A wafer loading / unloading chamber 8 serving as a transfer chamber is provided on the opposite side of the load lock chambers 6 and 7 to the processing units 2 and 3. Are provided with three connection ports 9, 10, and 11 for attaching a FOUP F capable of accommodating the wafer W. The internal structure of the wafer carry-in / out chamber 8 is shown in FIG. In FIG. 2, the hoop F is not shown for convenience of explanation.

  The two processing units 2 and 3 communicate with the load lock chambers 6 and 7 by opening each gate valve G1, and are disconnected from the load lock chambers 6 and 7 by closing each gate valve G1. A gate valve G2 is also provided at a portion of the load lock chambers 6 and 7 connected to the wafer loading / unloading chamber 8, and the load lock chambers 6 and 7 open and close the wafer by loading the gate valve G2. By communicating with the chamber 8 and closing them, the wafer loading / unloading chamber 8 is shut off.

  In the load lock chambers 6, 7, wafer transfer apparatuses 4, 5 for loading / unloading the wafer W as the object to be processed are provided between the processing units 2, 3 and the wafer loading / unloading chamber 8, respectively. Yes.

  Shutters 9a, 10a, and 11a (see FIG. 2) are provided in the three connection ports 9, 10, and 11 for attaching the FOUP F of the wafer carry-in / out chamber 8, respectively. A hoop F containing the wafer W or an empty hoop F is directly attached. When the hoop F is attached, the shutter is released to communicate with the wafer loading / unloading chamber 8 while preventing the outside air from entering. An alignment chamber 14 is provided on one side surface of the wafer carry-in / out chamber 8 where the wafer W is aligned.

In the wafer loading / unloading chamber 8, a wafer transfer device 16 for loading / unloading the wafer W into / from the FOUP F and loading / unloading the wafer W into / from the load lock chambers 6, 7 is provided. The wafer transfer device 16 can travel on the rail 18 along the direction in which the FOUPs F are arranged. The wafer transfer device 16 has an articulated arm 16a and a pick 17 for holding the wafer W at the tip thereof, and the wafer W is placed on the pick 17 and transferred. The pick 17 is made of a ceramic material such as alumina (Al ₂ O ₃ ), for example, and a plurality of, for example, four contact members 17 a that contact the wafer W protrude from the holding surface that holds the wafer W. Has been. The contact member 17a is formed of an elastomer material such as silicone resin, for example, and holds the wafer W so that the wafer W is not displaced on the pick 17 or dropped from the pick 17 due to the adhesive force thereof. .

In the wafer loading / unloading chamber 8, an ion generator 19 is disposed as a charging device that forcibly charges the pick 17 by supplying charged particles (ions) to the pick 17. A general-purpose ionizer can be used as the ion generator.
A fan filter unit (FFU) 20 that is an airflow generator is provided at the ceiling of the wafer loading / unloading chamber 8, and an exhaust fan unit is provided near the floor of the wafer loading / unloading chamber 8 so as to face the FFU 20. 21 is provided. As indicated by arrows in FIG. 2, clean air is supplied into the wafer loading / unloading chamber 8 by the FFU 20 in a downflow state and exhausted from the exhaust fan unit 21, so that a clean pressure of atmospheric pressure +1.3 Pa or more is obtained. The wafer W is loaded and unloaded in an air atmosphere. The ion generator 19 is preferably installed between the FFU 20 and the exhaust fan unit 21 on the downstream side (downward position) in the flow direction of the downflow airflow from the transfer position of the wafer W.

  Further, the plasma processing apparatus 1 includes a user interface 502 disposed at one end in the longitudinal direction of the wafer carry-in / out chamber 8. The user interface 502 includes a display unit (monitor) including an input unit (keyboard) and, for example, an LCD (Liquid Crystal Display), and the display unit displays the operation status of each component of the plasma processing apparatus 1.

  The control unit 30 performs overall control in the plasma processing apparatus 1 and control of gas introduction and exhaustion in the processing units 2 and 3. A schematic configuration of the control unit 30 is shown in FIG. The control unit 30 includes an EC (Equipment Controller) 301 that is a general control unit, and a plurality of, for example, two module controllers (Module Controller; hereinafter abbreviated as “MC”) provided corresponding to the processing units 2 and 3, respectively. 305a and 305b, an MC 306 provided in the wafer loading / unloading chamber 8, and a switching hub 304 that connects the EC 301 and the MCs 305a, 305b, and 306.

  The MC 305a connected to the processing unit 2 controls a process condition such as supply of high-frequency power for exciting plasma, gas introduction, exhaust, etc. during the plasma etching process performed in the processing unit 2. It is. Similarly, the MC 305b connected to the processing unit 3 is also a control unit that controls process conditions such as power supply, gas introduction, and exhaust performed in the processing unit 3.

The MC 306 connected to the wafer loading / unloading chamber 8 controls, for example, operation of the wafer transfer device 16, generation of downflow airflow by the FFU 20 and the exhaust fan unit 21, control of exhaust, and control of charging by the ion generator 19. It is a control part which performs etc.
Note that the MC can also be provided in, for example, the load lock chambers 6 and 7, and these are also integrated under the EC 301, but illustration and description thereof are omitted here.

  The control unit 30 is connected to a host computer 501 as a MES (Manufacturing Execution System) that manages the manufacturing process of the entire factory where the plasma processing apparatus 1 is installed from the EC 301 via a LAN (Local Area Network). Yes. The host computer 501 cooperates with the control unit 30 to feed back real-time information related to processes in the factory to a basic business system (not shown) and make a determination related to processes in consideration of the load of the entire factory.

  The EC 301 is an overall control unit that controls each of the MCs (for example, MCs 305a, 305b, and 306) and controls the operation of the entire plasma processing apparatus 1. Further, the EC 301 includes a CPU (not shown) and a storage unit 303 such as a RAM and an HDD, and a processing method (that is, a processing gas flow rate and a pressure) of the wafer W designated by the user or the like on the user interface 502. The CPU reads out the program corresponding to the recipe including the condition from the storage unit 303 and transmits it to the MCs 305a and 305b, so that the processing in each of the processing units 2 and 3 can be controlled.

  Further, the CPU of the EC 301 is a program for controlling the operation of the wafer transfer device 16, that is, a series of transfer operations such as loading / unloading of the wafer W into / from the FOUP F and loading / unloading of the wafer W into / from the load lock chambers 6 and 7. A program related to the control of the apparatus 19 and a program related to the control of the FFU 20 and the exhaust fan unit 21 are read from the storage unit 303 and transmitted to the MC 306 so that the MC 306 can control the transfer of the wafer W, the charging process of the pick 17, and the like. It is configured.

  Each MC 305a, 305b, 306 is connected to each I / O (input / output) module 308 via a network 309 realized by an LSI called GHOST (General High-Speed Optimum Scalable Transceiver). In the GHOST network 309, the MCs 305a and 305b correspond to master nodes, and the I / O module 308 corresponds to a slave node.

  The I / O module 308 connected to the MCs 305a and 305b has a plurality of I / O units 310 (only four are shown) connected to components (end devices) in the chambers of the processing units 2 and 3. The control signal to each end device and the output signal from the end device are transmitted. FIG. 3 representatively shows, for example, a mass flow controller (MFC) 53, a valve (VAL) 54, an exhaust device (EXHT) 56, a switch box (SW BOX) 313, and the like as end devices related to gas supply and pressure control. ing.

  The I / O module 308 connected to the MC 306 has a plurality of I / O units 310 (only four are shown) connected to each component (end device) of the wafer loading / unloading chamber 8. Transmits control signals to and output signals from end devices. Here, examples of the end device of the wafer loading / unloading chamber 8 include a wafer transfer device (TR) 16, an FFU 20, an exhaust fan unit (EFU) 21, a switch box (SW BOX) 313, an ion generator 19, and the like. be able to. In FIG. 3, for convenience, only connections between some end devices and the I / O unit 310 are representatively illustrated.

Each of the MCs 305a, 305b, and 306 is configured to exchange various signals and alarms via the I / O module 308, respectively. Thus, for example, when a status signal or an alarm signal is supplied from each end device to the I / O module 308, it is converted into a serial signal by the I / O board 310, and the switch unit (SW) 312 is transmitted via the local GHOST line. To the switch box (SW BOX) 313.
The GHOST network 309 is also connected to an I / O boat (not shown) that controls input / output of digital signals, analog signals, and serial signals in the I / O unit 310.

  The switching hub 304 switches between MCs 305a, 305b, and 306 as connection destinations of the EC 301 according to a control signal from the EC 301.

  In the control unit 30 shown in FIG. 3, the I / O module 310 is configured by modularizing the I / O unit 310 connected to the plurality of end devices without directly connecting the plurality of end devices to the EC 301. Since the I / O module 308 is connected to the EC 301 via the MCs 305a, 305b, and 306 and the switching hub 304, the communication system can be simplified.

  The control signals transmitted by the CPUs of the MCs 305a, 305b, and 306 include the address of the I / O unit 310 connected to the desired end device and the address of the I / O module 308 including the I / O unit 310. The GHOST of each MC 305a, 305b, 306 refers to the address of the I / O unit 310 in the control signal, thereby eliminating the need for the switching hub 304 or the like to query the CPU for the destination of the control signal. Thus, smooth transmission of the control signal can be realized.

  Further, the control unit 30 may include a data collection server 314 as a data collection / recording unit that economically collects and records data output from any end device. In this case, the data signal output from the end device is extracted as an analog signal, input to the I / O unit 310, and input to the data collection server 314 via the GHOST network 309 or the LAN.

  According to the plasma processing apparatus 1 configured as described above, since the MCs 305a, 305b, and 306 that perform control under the control of the EC 301 that is the overall control unit are provided, the processing operation by each end device is highly reliable. Can be controlled.

  In such a plasma processing apparatus 1, first, one wafer W is transferred from any one of the hoops F by the wafer transfer device 16 in the wafer carry-in / out chamber 8 held in a clean air atmosphere of atmospheric pressure + 1.3 Pa or higher. The wafer W is taken out and loaded into the alignment chamber 14, and the wafer W is aligned. Next, after the wafer W is loaded into one of the load lock chambers 6 and 7 and the load lock chamber is evacuated, the wafer W is transferred to the processing unit 2 or 3 by the wafer transfer device 4 or 5. Then, an etching process is performed. Thereafter, the wafer W is loaded into one of the load lock chambers 6 and 7 by any one of the wafer transfer devices 4 and 5, the inside thereof is returned to atmospheric pressure, and then the wafer transfer device 16 in the wafer carry-in / out chamber 8 is used. The wafer W in the load lock chamber is taken out and accommodated in one of the FOUPs F. Such an operation is performed on one lot of wafers W, and one lot of processing is completed.

  At the stage where the processing of a predetermined number of wafers or a predetermined lot of wafers W is completed, the pick 17 of the wafer transfer device 16 is periodically cleaned. In cleaning, first, as shown in FIG. 4, the pick 17 of the wafer transfer device 16 is moved to just below the ion generator 19. Next, the ion generator 19 is powered on to supply charged particles toward the pick 17. In FIG. 4, negatively charged particles (negative ions) are supplied from the ion generator 19 to the pick 17, and the contact member 17 a of the pick 17 is forcibly negatively charged. At this time, the charged state of the contact member 17a of the pick 17 is detected by a sensor (not shown) provided in the ion generator 19 so that the contact member 17a of the pick 17 has a desired polarity and charge amount. While being charged.

  Since the particles adhering to the surface of the contact member 17a of the pick 17 are normally negatively charged, the particles are removed from the contact member 17a by the repulsive force of static electricity by forcibly negatively charging the contact member 17a. Can be withdrawn. Note that positively charged particles may be supplied from the ion generator 19 to the pick 17 to forcibly charge the abutting member 17a of the pick 17, or may be positively charged and negatively charged as described later. The state may be repeated alternately.

  During cleaning, the FFU 20 generates a downflow air flow in the wafer carry-in / out chamber 8 and exhausts air from the exhaust fan unit 21 to quickly remove particles removed from the pick 17 from the wafer carry-in / out chamber 8. It becomes possible to discharge. As shown in FIG. 2, the ion generator 19 is installed below the height of the transfer path for transferring the wafer W and above the exhaust fan unit 21, so that particles are discharged by the downflow airflow. Is promoted. Therefore, the particles removed from the pick 17 do not diffuse in the wafer carry-in / out chamber 8 and secondary contamination is prevented.

  FIG. 5 is a flowchart showing a preferred example of the cleaning process procedure of the pick 17 performed in the plasma processing apparatus 1. As described above, in the plasma processing apparatus 1 according to the present embodiment, cleaning can be performed by forcibly charging the contact member 17a of the pick 17 to either positive or negative polarity. However, when the particles are firmly attached to the contact member 17a, there are cases where the particles cannot be reliably removed by a single charge. In such a case, cleaning can be more reliably performed by the following procedure.

  In the plasma processing apparatus 1, when processing of a predetermined number of wafers or a predetermined lot of wafers W is completed and the processed wafers W are loaded into the FOUP F, the wafer transfer apparatus 16 is in a standby state (from the EC 301 to the MC 306 of the control unit 30 ( A control signal instructing (idle state) is transmitted. In response to this control signal, cleaning is started under the control of the MC 306.

  First, in step S1, the pick 17 of the wafer transfer device 16 is moved to a predetermined cleaning position, for example, a position directly below the ion generator 19 as shown in FIG. Next, in step S <b> 2, a downflow airflow is generated in the wafer carry-in / out chamber 8 by the FFU 20, and exhaust is performed from the exhaust fan unit 21. In step S <b> 3, the ion generator 19 is turned on (on) to supply charged particles (ions) toward the pick 17. At this time, based on the cleaning recipe program read from the storage unit 303 of the EC 301 and sent to the MC 306, the MC 306 alternately supplies positive / negative charged particles from the ion generator 19 to the pick 17 at predetermined intervals. To control. As a result, the contact member 17a of the pick 17 is forcibly repeatedly charged positively / negatively. At this time, charging is performed while detecting the charged state of the pick 17 by a sensor (not shown) provided in the ion generator 19 so that the contact member 17a of the pick 17 has a desired polarity and charge amount. . As described above, by repeating the positive / negative alternating charging state, it is possible to reliably remove particles adhering to the contact member 17a of the pick 17.

  When positive / negative charging is completed for a predetermined time (or a predetermined number of times), a neutralization process is performed to adjust the charged state by supplying charged particles having a polarity opposite to the polarity of the charged particles supplied last (step) S4). If cleaning is completed while the pick 17 is strongly charged to either positive / negative polarity, the wafer W may be attracted to the pick 17 during transfer. Further, if the pick 17 is strongly charged, particles having opposite polarity are likely to be attracted, and the pick 17 may be contaminated. For this reason, in step S4, an appropriate amount of charged particles (for example, positive ions) having a polarity opposite to that of the last charged state (for example, negative) in step S3 is supplied to neutralize the pick 17 including the contact member 17a, for example. In the neutralization process in step S4, the contact member 17a does not need to be completely neutralized. For example, when the wafer W is subsequently transported, it is weakly negatively charged so that particles are less likely to adhere. It is also possible.

  After the neutralization process is finished, the cleaning process is finished. After the cleaning is completed, the wafer transfer device 16 is placed in a standby state (idle state) until the next wafer W is instructed from the EC 301 of the control unit 30 via the MC 306. Thus, by performing the cleaning using the standby time of the wafer transfer device 16, the down time of the plasma processing apparatus 1 accompanying the cleaning can be reduced.

  In the plasma processing apparatus 1 according to the above embodiment, the ion generator 19 is arranged in the wafer carry-in / out chamber 8 and the pick 17 of the wafer transfer device 16 is cleaned in the wafer carry-in / out chamber 8. As in the plasma processing apparatus 100 shown in FIG. 6, the cleaning chamber 40 is provided adjacent to the wafer carry-in / out chamber 8, and the pick 17 can be cleaned there. In the plasma processing apparatus 100 shown in FIG. 6, a cleaning chamber 40 is provided on the side surface of the wafer carry-in / out chamber 8 facing the alignment chamber 14. The cleaning chamber 40 is provided with an ion generator 19. After the wafer transfer device 16 is moved to the vicinity of the cleaning chamber 40, the arm 16 a is extended and the pick 17 is inserted into the cleaning chamber 40. Thus, cleaning can be performed by charging the contact member 17a.

  In the cleaning chamber 40, an FFU and an exhaust fan unit (both not shown) are provided in the same manner as the wafer loading / unloading chamber 8, and the particles removed from the pick 17 are quickly discharged together with the downflow airflow. It is configured to be able to. 6 is the same as that of the plasma processing apparatus 1 shown in FIG. 1, the same components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 7 is an enlarged perspective view of the pick 101 in the wafer conveyance device of another embodiment, and FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. The pick 101 is provided at the tip of an arm 102 in a wafer transfer device (not shown). On the holding surface of the pick 101 for holding the wafer W, a plurality of, for example, four contact members 101 a that contact the wafer W are projected.

As shown in FIG. 8, the pick 101 has a multilayer structure in which the periphery of the conductive member 103 is covered with the insulating member 104. The conductive member 103 can be formed of a sprayed film of a conductive metal such as tungsten. The insulating member 104 can be formed of a ceramic sprayed film such as alumina (Al ₂ O ₃ ). The conductive member 103 is electrically connected to the DC power source 106 through a power supply line 105 disposed inside the arm 102.

  The pick 101 of this embodiment is a pick having a self-cleaning function for removing particles and deposits attached to the contact member 101a. The pick 101 is cleaned by applying a DC voltage having a predetermined polarity to the conductive member 103 from the DC power source 106 via the power supply line 105. By applying a voltage to the conductive member 103, the surface of the pick 101, that is, the surface of the insulating member 104 and the surface of the contact member 101a can be charged.

At the time of cleaning, a voltage is applied to the conductive member 103 so that the contact member 101a is charged with the same polarity as the particles attached thereto. FIG. 8 shows a state in which the surface of the contact member 101a and the insulating member 104 is negatively charged in the same manner as the particles by applying a positive polarity voltage from the DC power source 106 to the conductive member 103. . By charging the contact member 101a of the pick 101 in this way, particles adhering to the contact member 101a can be separated by the repulsive force of the charge and removed from the contact member 101a.
Note that a negative polarity voltage may be supplied from the DC power source 106 to the pick 101 to forcibly charge the abutting member 101a of the pick 101, or a positive charging state and a negative charging as described later. You may switch and apply a positive / negative voltage so that a state may be repeated alternately.

  The pick 101 having the above configuration can be used as it is in place of the pick 17 in the plasma processing apparatus 1 shown in FIG. Therefore, description and illustration of the plasma processing apparatus provided with the pick 101 are omitted. Since the pick 101 has a self-cleaning function, when the pick 101 is provided in the plasma processing apparatus 1, the ion generator 19 may not be provided. At the time of cleaning, the pick 101 is moved to a predetermined cleaning position, for example, below the height of the transfer path of the wafer W in the wafer carry-in / out chamber 8 and to a position above the exhaust fan unit 21, and from the DC power source 106. A DC voltage having a predetermined polarity may be applied to the conductive member 103 through the feeder line 105.

  During cleaning, the FFU 20 generates a downflow air flow in the wafer carry-in / out chamber 8 and exhausts air from the exhaust fan unit 21 to quickly remove particles removed from the pick 101 from the wafer carry-in / out chamber 8. It becomes possible to discharge. Cleaning is performed by moving the pick 101 to a position below the height of the transfer path for transferring the wafer W, so that particles removed from the pick 101 using the downflow airflow of the FFU 20 can be quickly transferred to the exhaust fan unit 21. Thus, the particles can be prevented from diffusing in the wafer loading / unloading chamber 8.

  Further, the pick 101 of this embodiment can be used as it is in place of the pick 17 in the plasma processing apparatus 100 of the embodiment shown in FIG. In this case, the pick 101 is moved to the cleaning chamber 40 disposed adjacent to the wafer carry-in / out chamber 8 for cleaning. In addition, since the pick 101 has a self-cleaning function, it is not necessary to provide the ion generator 19 in the cleaning chamber 40.

  Furthermore, the pick 101 can be moved to one of the load lock chambers 6 and 7 shown in FIGS. 1 and 6 and cleaning can be performed there. The load lock chambers 6 and 7 that repeat the vacuum state and the air release state are provided with a purge gas supply means (not shown) and an exhaust means such as a dry pump, so that the exhaust gas is introduced by introducing the purge gas from the purge gas supply means. By exhausting, particles detached from the pick 101 by cleaning can be quickly discharged from the load lock chambers 6 and 7. Therefore, the pick 101 can be cleaned while preventing secondary contamination in the load lock chambers 6 and 7.

  FIG. 9 is a flowchart showing a preferred example of the processing procedure for cleaning the pick 101. When the particles are firmly attached to the contact member 101a, there are cases where the particles cannot be reliably removed by a single charge. In such a case, cleaning can be more reliably performed by the following procedure. In the following description, cleaning is performed in the plasma processing apparatus 1 having the same configuration as that in FIG. 1 except that the ion generator 19 is not provided.

  In the plasma processing apparatus 1, when processing of a predetermined number of wafers or a predetermined lot of wafers W is completed and the processed wafers W are loaded into the FOUP F, the wafer transfer apparatus 16 is in a standby state (from the EC 301 to the MC 306 of the control unit 30 ( A control signal instructing (idle state) is transmitted. In response to this control signal, cleaning is started under the control of the MC 306.

  First, in step S11, the pick 101 of the wafer transfer device 16 is moved to a vicinity of the exhaust port of the exhaust fan unit 19 at a predetermined cleaning position, for example, a position below the height of the transfer path for transferring the wafer W. Next, in step S <b> 12, the FFU 20 generates a downflow airflow in the wafer carry-in / out chamber 8 and exhausts air from the exhaust fan unit 21.

  In step S <b> 13, the DC power source 106 is turned on (on), and a DC voltage is applied to the conductive member 103 of the pick 101 via the feeder line 105. At this time, based on the cleaning recipe program read from the storage unit 303 of the EC 301 and sent to the MC 306, the MC 306 alternately supplies positive / negative DC voltages from the DC power source 106 to the pick 101 at predetermined intervals. To control. As a result, the contact member 101a of the pick 101 is forcibly and repeatedly positively / negatively charged. As described above, by repeating the positive / negative alternating charging state, it is possible to reliably remove particles adhering to the contact member 101a of the pick 101.

  When positive / negative charging is completed for a predetermined time (or a predetermined number of times), neutralization is performed to adjust the charging state by supplying a voltage having a polarity opposite to the polarity of the DC voltage supplied last (step S14). ). If cleaning is completed while the pick 101 is strongly charged with either positive or negative polarity, the wafer W may be attracted to the pick 101 during transfer. Further, if the pick 101 is strongly charged, particles having opposite polarity are likely to be attracted, which may cause the pick 101 to be contaminated. For this reason, in step S14, a voltage (for example, a positive voltage) opposite in polarity to the last applied voltage (for example, a negative voltage) in step S13 is supplied to neutralize the pick 101 including the contact member 101a. In the neutralization process in step S14, it is not necessary to completely remove the charge from the contact member 101a. For example, when the wafer W is subsequently transported, it is weakly negatively charged so that particles are less likely to adhere. It is also possible.

  After the neutralization process is finished, the cleaning process is finished. After the cleaning is completed, the wafer transfer device 16 is placed in a standby state (idle state) until the next wafer W is instructed from the EC 301 of the control unit 30 via the MC 306. Thus, by performing the cleaning using the standby time of the wafer transfer device 16, the down time of the plasma processing apparatus 1 accompanying the cleaning can be reduced.

  The embodiments of the present invention have been described above with some examples, but the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in the above-described embodiment, a plasma processing apparatus that performs plasma etching has been described as an example. However, the present invention is not limited to this, and any etching apparatus can be used as long as the substrate processing apparatus includes a pick that holds a substrate such as a wafer W. The present invention can be applied not only to the apparatus.

Further, the number and arrangement of the processing units in the plasma processing apparatus are not limited to those shown in FIG. 1 (FIG. 6), and can be applied to a multi-chamber type plasma processing apparatus provided with more processing units. Further, the transfer device for transferring the substrate such as the wafer W is not limited to the one illustrated in FIG. 1 (FIG. 6), and other types of transfer devices such as a transfer device having two SCARA arm type transfer arms, for example. Can be applied to.
Further, the type of substrate held by the pick is not limited to a semiconductor wafer, and the idea of the present invention can be applied to a large pick used for transporting a large substrate such as a glass substrate for a flat panel display (FPD). .

  The present invention can be used in a substrate processing apparatus that transports a substrate using a pick such as a semiconductor device manufacturing process.

BRIEF DESCRIPTION OF THE DRAWINGS Drawing which shows schematic structure of the plasma processing apparatus of one Embodiment of this invention. Drawing which shows the internal structure of a wafer carrying in / out chamber. The figure which shows schematic structure of a control part. The figure which illustrates typically the state which is charging the contact member of a pick. The flowchart which shows an example of the process sequence of the cleaning method of this invention. The figure which shows schematic structure of the plasma processing apparatus of another embodiment. The perspective view which shows embodiment of a pick. Sectional drawing of the VIII-VIII line arrow in FIG. The flowchart which shows another example of the process sequence of the cleaning method of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Plasma processing apparatus 2; Processing unit 3; Processing unit 16; Wafer transfer apparatus 16a; Arm 17; Pick 17a; Abutting member 19; Ion generator 20: Fan filter unit (FFU)
21; exhaust filter unit 100; plasma processing apparatus 101; pick 102; arm W; wafer

Claims (19)

In a transfer device for transferring a substrate, a transfer pick attached to the tip of a transfer arm and holding a substrate on a substrate holding surface,
A plurality of abutting members that project from the substrate holding surface and abut against the substrate;
A voltage application device for charging the contact member;
A transport pick having a self-cleaning function for removing particles adhering to the contact member by a repulsive force of electric charge. The transport pick has a conductive member and an insulating member covering the periphery thereof,
The transport pick according to claim 1, wherein the voltage application device is electrically connected to the conductive member and applies a positive or negative voltage to the conductive member.   A transport apparatus comprising the transport pick according to claim 1. A substrate processing apparatus comprising: a processing chamber that performs a predetermined process on a substrate; and a transfer chamber in which a transfer device that transfers the substrate to the processing chamber is provided.
The said transfer apparatus is a substrate processing apparatus provided with the transfer pick of Claim 1 or Claim 2. A vacuum processing chamber for performing predetermined processing on the substrate, a transfer chamber in which a transfer device for transferring the substrate to the vacuum processing chamber is provided, and a vacuum preparatory chamber disposed between the vacuum processing chamber and the transfer chamber A substrate processing apparatus comprising:
The transfer device includes a transfer arm, and a transfer pick attached to the tip of the transfer arm and having a plurality of abutting members protruding from a substrate holding surface that holds the substrate.
A substrate processing apparatus comprising a charging device that supplies charged particles to the contact member and forcibly charges the contact member.   The substrate processing apparatus according to claim 5, wherein the charging device applies a voltage so that the contact member is charged with the same polarity as the particles attached thereto.   The substrate processing apparatus according to claim 5, wherein the charging device is disposed in the transfer chamber. In the transfer chamber, an airflow forming device that forms a forced airflow in the transfer chamber and an exhaust device that exhausts the transfer chamber are provided.
The substrate processing apparatus according to claim 7, wherein the charging device is disposed at a position downstream of the substrate transport position by the transport device in the airflow direction.   The substrate processing apparatus according to claim 5, wherein the charging device is provided in a cleaning chamber provided adjacent to the transfer chamber.   The substrate processing apparatus according to claim 9, wherein an airflow forming device that forms a forced airflow in the cleaning chamber and an exhaust device that exhausts the cleaning chamber are provided in the cleaning chamber.   The substrate processing apparatus according to claim 5, wherein the charging device is provided in the vacuum preliminary chamber.   A substrate holding surface that is attached to a tip of a transfer arm of a transfer device that transfers a substrate in the substrate processing apparatus, a plurality of contact members that protrude from the substrate holding surface and come into contact with the substrate, and the contact A voltage picking device for charging a member is repeatedly applied so that the charging polarity of the contact member is alternately switched between positive and negative by alternately applying positive and negative voltages by the voltage applying device. A transport pick cleaning method including a cleaning step of forcibly charging and removing particles adhering to the contact member by a repulsive force of electric charges.   The substrate processing apparatus includes a substrate holding surface that is attached to a tip of a transfer arm of a transfer device that transfers a substrate and holds the substrate, and a plurality of contact members that protrude from the substrate holding surface and come into contact with the substrate. A charging device that supplies charged particles to the abutting member with respect to the transport pick is repeatedly forcibly charged so that the charging polarity of the abutting member is alternately switched between positive and negative, and the repulsive force of the electric charge causes the abutting member to A transport pick cleaning method including a cleaning step of removing attached particles.   14. The method for cleaning a transfer pick according to claim 12, wherein the cleaning step is performed during an idle time of the transfer device in the substrate processing apparatus.   The method for cleaning a transport pick according to claim 12, wherein an airflow is generated by an airflow generator in a room in which the transport pick is disposed during the cleaning step.   The substrate processing apparatus includes: a vacuum processing chamber that performs a predetermined process on the substrate; a transfer chamber in which the transfer device that transfers the substrate to the vacuum processing chamber is disposed; and between the vacuum processing chamber and the transfer chamber The vacuum picking chamber according to claim 15, wherein the cleaning step is performed in the transfer chamber or the vacuum preparatory chamber.   The method of cleaning a transport pick according to any one of claims 12 to 16, further comprising a step of adjusting a charged state of the contact member after the cleaning.   A control program that operates on a computer and controls the substrate processing apparatus so that the transport pick cleaning method according to any one of claims 12 to 17 is performed at the time of execution. A computer-readable storage medium storing a control program that runs on a computer,
A computer-readable storage for controlling the substrate processing apparatus so that, when executed, the method for cleaning a transfer pick according to any one of claims 12 to 17 is performed. Medium.

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