JP6169891B2 - Substrate cleaning device - Google Patents

Description

  The present invention relates to a substrate cleaning apparatus for scrub cleaning the surface of a substrate by rotating both the substrate and the roll cleaning member while bringing the roll cleaning member into contact with the surface of the substrate such as a semiconductor wafer in the presence of a cleaning liquid. The substrate cleaning apparatus of the present invention is suitably used for cleaning a substrate surface when manufacturing a semiconductor manufacturing apparatus, an LCD (liquid crystal display) apparatus, a PDP (plasma display) apparatus, a CMOS image sensor, or the like.

  In the damascene wiring formation process, excess metal is removed from the substrate surface by chemical mechanical polishing (CMP) after the wiring is formed. On the substrate surface after CMP, there are slurry residues (slurry residues) used in CMP, metal scraps, and the like. For this reason, it is necessary to remove the residue remaining on the substrate surface.

  As an apparatus for cleaning the surface of a substrate after CMP, in the presence of a cleaning solution, a substrate and a roll cleaning member are rotated together while contacting a cylindrical roll cleaning member (roll sponge or roll brush) with the surface of the substrate. A substrate cleaning apparatus for cleaning the surface of the substrate is known (see Patent Document 1).

Japanese Patent Laid-Open No. 10-308374

  In the conventional substrate cleaning apparatus, the roll cleaning member is pressed against the surface of the substrate by the weight of the roll cleaning member and the motor that rotates the roll cleaning member. Therefore, the maximum load that the roll cleaning member applies to the substrate is the weight of the roll cleaning member and the motor. When a load smaller than the dead weight is applied to the substrate, the motor is pushed up by the air cylinder. However, with such a mechanism that cancels its own weight using the pressure of gas, it is difficult to accurately control the load on the substrate in the low load region.

  The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a substrate cleaning apparatus capable of pressing a roll cleaning member against a substrate with a stable low load.

In order to achieve the above-described object, one embodiment of the present invention includes a cleaning mechanism that includes a roll cleaning member that contacts a surface of a substrate and a rotation mechanism that rotates the roll cleaning member, and a variable downward load. and the weight mechanism for generating the weight of itself, the downward load is converted into upward load, and a load transmitting mechanism for transmitting the load of the upper direction to the cleaning mechanism, the weight mechanism, the liquid inside In the substrate cleaning apparatus, the downward load is generated by the dead weight of the tank and the liquid .

In a preferred aspect of the present invention, the weight mechanism further includes a supply line for supplying the liquid to the tank and a discharge line for discharging the liquid from the tank.
One aspect of the present invention includes a cleaning mechanism that includes a roll cleaning member that contacts a surface of a substrate and a rotation mechanism that rotates the roll cleaning member, and a weight that generates a variable downward load by its own weight. And a load transmission mechanism that converts the downward load into an upward load and transmits the upward load to the cleaning mechanism. The load transmission mechanism passes through the pulley from the weight mechanism and the pulley. a substrate cleaning apparatus; and a cord extending to the cleaning mechanism and.
In a preferred aspect of the present invention, the apparatus further includes a raising mechanism that raises the cleaning mechanism.
In a preferred aspect of the present invention, the raising mechanism is an air cylinder.

  According to the present invention, the load on the substrate of the roll cleaning member is determined by the weight of the weight mechanism. That is, the load applied to the substrate is a weight obtained by subtracting the weight of the weight mechanism from the weight of the cleaning mechanism. In this way, in the present invention, the load of the roll cleaning member is controlled not by the pressure of the gas but by the weight of the weight mechanism, so that the roll cleaning member can apply a stable load to the substrate even in a low load region. .

It is a top view which shows the whole structure of the substrate processing apparatus provided with the substrate cleaning apparatus which concerns on embodiment of this invention. 1 is a perspective view showing a substrate cleaning apparatus according to an embodiment of the present invention. It is a schematic diagram of a substrate cleaning apparatus.

  FIG. 1 is a plan view showing an overall configuration of a substrate processing apparatus including a substrate cleaning apparatus according to an embodiment of the present invention. As shown in FIG. 1, the substrate processing apparatus includes a substantially rectangular housing 10 and a load port 12 on which a substrate cassette for stocking substrates such as a number of semiconductor wafers is placed. The load port 12 is disposed adjacent to the housing 10. The load port 12 can be mounted with an open cassette, a SMIF (Standard Manufacturing Interface) pod, or a FOUP (Front Opening Unified Pod). SMIF and FOUP are sealed containers that can maintain an environment independent of the external space by accommodating a substrate cassette inside and covering with a partition wall.

  Inside the housing 10, a plurality of (four in this embodiment) polishing units 14a to 14d, a first cleaning unit 16 and a second cleaning unit 18 for cleaning the substrate after polishing, and a substrate after cleaning are dried. A drying unit 20 is accommodated. The polishing units 14a to 14d are arranged along the longitudinal direction of the substrate processing apparatus, and the cleaning units 16, 18 and the drying unit 20 are also arranged along the longitudinal direction of the substrate processing apparatus.

  In a region surrounded by the load port 12, the polishing unit 14a, and the drying unit 20, a first substrate transfer robot 22 is disposed, and a substrate transfer unit 24 is disposed in parallel with the polishing units 14a to 14d. The first substrate transfer robot 22 receives the substrate before polishing from the load port 12 and passes it to the substrate transfer unit 24, and receives the dried substrate from the drying unit 20 and returns it to the load port 12. The substrate transport unit 24 transports the substrate received from the first substrate transport robot 22 and delivers the substrate to and from each of the polishing units 14a to 14d. Each polishing unit polishes the surface of the substrate by bringing a substrate such as a wafer into sliding contact with the polishing surface while supplying a polishing liquid (slurry) to the polishing surface.

  A second substrate transport robot 26 is disposed between the first cleaning unit 16 and the second cleaning unit 18 and transports a substrate between these units 16, 18, and the second cleaning unit 18 and the drying unit. A third substrate transport robot 28 is disposed between the units 18 and 20 so as to be positioned between the units 18 and 20. Further, a control unit 30 that controls the movement of each unit of the substrate processing apparatus is disposed inside the housing 10.

  In this example, as the first cleaning unit 16, a substrate cleaning apparatus according to an embodiment of the present invention that cleans a substrate by rubbing a roll cleaning member on both the front and back surfaces of the substrate in the presence of a cleaning liquid is used. A pen sponge type substrate cleaning apparatus is used as the second cleaning unit 18. As the drying unit 20, a spin drying apparatus is used that holds a substrate, blows IPA vapor from a moving nozzle to dry the substrate, and further rotates the substrate at high speed to dry the substrate by centrifugal force.

  As shown in FIG. 2, the substrate cleaning apparatus used as the first cleaning unit 16 includes a plurality of (four in the figure) rollers 54 that support the peripheral edge of the substrate W and rotate the substrate W horizontally, and the rollers 54. The upper roll holder 42 is disposed above and below the substrate W supported by the roller 54 and the lower roll holder 44 is disposed below the substrate W supported by the roller 54 so as to be movable up and down. The roller 54 is configured to move horizontally in the direction of approaching and separating from the substrate W as indicated by arrows. The roller 54 is a substrate holder that holds and rotates the substrate W horizontally.

  A cylindrical upper roll cleaning member (roll sponge) 46 made of, for example, PVA is rotatably supported on the upper roll holder 42. A cylindrical lower roll cleaning member (roll sponge) 48 made of PVA, for example, is rotatably supported on the lower roll holder 44. As the roll cleaning members 46 and 48, roll brushes having brushes on the surface may be used instead of the roll sponge.

  The upper roll cleaning member 46 is connected to a motor 56 that rotates the upper roll cleaning member 46 as indicated by an arrow F1. The lower roll holder 44 is connected to a motor 57 that rotates the lower roll holder 44 as shown by an arrow F2.

  The substrate W is held by the roller 54 with the surface on which the device is formed facing upward. An upper cleaning liquid supply nozzle 50 that supplies a cleaning liquid to the front surface (upper surface) of the substrate W is disposed above the substrate W supported by the roller 54, and is positioned below the substrate W to be connected to the rear surface ( A lower cleaning liquid supply nozzle 52 for supplying the cleaning liquid is disposed on the lower surface. A chemical solution is used as the cleaning solution.

  The peripheral edge of the substrate W is supported by an annular groove 54 a formed on the outer peripheral surface of the roller 54. In this state, by rotating (spinning) the roller 54 while pressing the roller 54 against the substrate W, the substrate W is rotated horizontally as indicated by an arrow E around its central axis. In this example, two of the four rollers 54 give a rotational force to the substrate W, and the other two rollers 54 function as bearings that receive the rotation of the substrate W. Note that all the rollers 54 may be connected to a drive mechanism (not shown) to apply a rotational force to the substrate W.

  In this way, the cleaning liquid is supplied from the upper cleaning liquid supply nozzle 50 to the surface (upper surface) of the substrate W while rotating the substrate W horizontally. In this state, the upper roll cleaning member 46 is moved downward while being rotated by the motor 56 and brought into contact with the surface of the rotating substrate W, whereby the surface of the substrate W is scrubbed by the upper roll cleaning member 46 in the presence of the cleaning liquid. Wash. The length of the upper roll cleaning member 46 is slightly longer than the diameter of the substrate W, and the entire surface of the substrate W is cleaned by the upper roll cleaning member 46.

  At the same time, the cleaning liquid is supplied from the lower cleaning liquid supply nozzle 52 to the back surface (lower surface) of the substrate W. In this state, the lower roll cleaning member 48 is raised while being rotated by the motor 57 and brought into contact with the back surface of the rotating substrate W, whereby the back surface of the substrate W is brought into contact with the lower roll cleaning member 48 in the presence of the cleaning liquid. Scrub with. The length of the lower roll cleaning member 48 is slightly longer than the diameter of the substrate W, and the entire back surface of the substrate W is cleaned by the lower roll cleaning member 48.

  FIG. 3 is a schematic view showing an embodiment of the substrate cleaning apparatus of the present invention. As shown in FIG. 3, the upper roll cleaning member 46 is connected to a motor (rotating mechanism) 56. The upper roll cleaning member 46 is rotated by a motor 56 around its own axis extending in parallel with the surface of the substrate W while being in contact with the surface of the substrate W held by the roller 54. The upper roll cleaning member 46, the upper roll holder 42, and the motor 56 move up and down together. Hereinafter, the upper roll cleaning member 46, the upper roll holder 42, and the motor 56 may be collectively referred to as a cleaning mechanism 61 in the following description.

  An air cylinder 63 as a raising mechanism is connected to the cleaning mechanism 61, and the cleaning mechanism 61 is raised by the air cylinder 63. Further, the cleaning mechanism 61 is connected to a weight mechanism 81 via a load transmission mechanism 71. The weight mechanism 81 includes a tank 82 that can store liquid therein, and generates a downward load due to the weight of the tank 82 itself and the weight of the liquid in the tank 82. The weight mechanism 81 further includes a supply line 84 for supplying liquid to the tank 82, a discharge line 85 for discharging liquid from the tank 82, a first valve 86 provided in the supply line 84, and a discharge And a second valve 87 provided in the line 85.

  The supply line 84 is connected to a liquid supply source (not shown) so that a liquid (for example, pure water) is supplied into the tank 82 through the supply line 84. The amount of liquid held in the tank 82 can be adjusted by supplying and discharging liquid through the supply line 84 and the discharge line 85. More specifically, when the first valve 86 is opened, the liquid is supplied to the tank 82, and when the first valve 86 is closed, the supply of the liquid to the tank 82 is stopped. Furthermore, the liquid stored in the tank 82 can be discharged to the outside by opening the second valve 87.

  The tank 82 is supported by a linear guide mechanism 90 extending in the vertical direction so as to be movable up and down. The linear guide mechanism 90 is a device that guides the vertical movement of the tank 82. The weight mechanism 81 generates a downward load due to the weight of the tank 82 and the liquid existing therein. As shown in FIG. 3, the tank 82 may have a balance weight 82a as an additional weight.

  The load transmission mechanism 71 includes a pulley 72 configured to be freely rotatable and a string 75 hung on the pulley 72. Examples of the string 75 include a thread, a rope, a belt, and a wire. One end of the string 75 is connected to the tank 82 of the weight mechanism 81, and the other end of the string 75 is connected to the cleaning mechanism 61. The string 75 extends from the weight mechanism 81 to the cleaning mechanism 61 via the pulley 72. The downward load generated by the weight mechanism 81 is converted into an upward load by the load transmission mechanism 71 and transmitted to the cleaning mechanism 61.

  Next, the operation of the substrate cleaning apparatus shown in FIG. 3 will be described. The motor 56 is driven to rotate the upper roll cleaning member 46 around its central axis. In a state where air is not supplied to the air cylinder 63, the second valve 87 is opened to discharge the liquid from the tank 82 little by little. When the downward load generated by the weight mechanism 81 reaches a predetermined value, the second valve 87 is closed. When the total weight of the tank 82 and the liquid becomes smaller than the weight of the cleaning mechanism 61, the cleaning mechanism 61 is lowered and the upper roll cleaning member 46 comes into contact with the substrate W before long. The upper roll cleaning member 46 is in sliding contact with the surface of the substrate W, whereby the surface of the substrate W is scrubbed. During the cleaning of the substrate W, the cleaning liquid is supplied to the surface of the substrate W.

  The downward load generated by the weight mechanism 81 is determined in advance based on the weight of the cleaning mechanism 61. For example, the downward load generated by the weight mechanism 81 during the cleaning of the substrate W is set to be slightly smaller than the own weight of the cleaning mechanism 61. In this case, most of the weight of the cleaning mechanism 61 is offset by the upward load transmitted from the load transmission mechanism 71, and the remaining weight of the cleaning mechanism 61 is added to the surface of the substrate W. The downward load generated by the weight mechanism 81 can be determined from the liquid level of the liquid stored in the tank 82. That is, the downward load generated by the weight mechanism 81 can be determined from the liquid level in the tank 82 based on the relationship between the liquid level and the downward load acquired in advance.

  When the cleaning of the substrate W is completed, air is supplied to the air cylinder 63 and the entire cleaning mechanism 61 is lifted by the air cylinder 63. The upper roll cleaning member 46 is separated from the surface of the substrate W, and then the supply of the cleaning liquid to the substrate W is stopped.

  According to the above-described embodiment, the load on the substrate W of the upper roll cleaning member 46 is controlled by the weight of the weight mechanism 81, so that the upper roll cleaning member 46 stably applies a low load during the cleaning of the substrate W. Can be given to the surface.

  When the upper roll cleaning member 46 is made of a roll sponge or a roll brush, the weight of the upper roll cleaning member 46 is different between the dry state and the wet state. Therefore, the weight of the weight mechanism 81 may be changed depending on the state of the upper roll cleaning member 46. For example, when the upper roll cleaning member 46 in the dry state is lowered, the liquid is discharged from the tank 82 until the upper roll cleaning member 46 starts to descend, and the upper roll cleaning member 46 is in a wet state after the cleaning is started. At this time, the liquid is supplied to the tank 82 until the weight of the weight mechanism 81 reaches a predetermined value.

  As the load transmission mechanism 71, a link mechanism including a link and a joint (node) may be used instead of the combination of the pulley 72 and the string 75.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 10 Housing 12 Load port 14a-14d Polishing unit 16 1st washing | cleaning unit (board | substrate washing | cleaning apparatus)
18 Second cleaning unit 20 Drying unit 22 First substrate transfer robot 24 Substrate transfer unit 26 Second substrate transfer robot 28 Third substrate transfer robot 30 Control unit 42 Upper roll holder 44 Lower roll holder 46 Upper roll cleaning member 48 Lower side Roll cleaning member 50 Upper cleaning liquid supply nozzle 52 Lower cleaning liquid supply nozzle 54 Roller 56 Motor 57 Motor 61 Cleaning mechanism 63 Air cylinder (lifting mechanism)
71 Load transmission mechanism 72 pulley 75 string 81 weight mechanism 82 tank 84 supply line 85 discharge line 86 first valve 87 second valve 90 linear guide mechanism

Claims (5)

A vertically movable cleaning mechanism including a roll cleaning member that contacts the surface of the substrate and a rotation mechanism that rotates the roll cleaning member;
A weight mechanism that generates a variable downward load by its own weight;
A load transmission mechanism that converts the downward load into an upward load and transmits the upward load to the cleaning mechanism ;
The substrate cleaning apparatus , wherein the weight mechanism includes a tank capable of storing a liquid therein, and generates the downward load by the weight of the tank and the liquid . The substrate cleaning apparatus according to claim 1 , wherein the weight mechanism further includes a supply line for supplying a liquid to the tank and a discharge line for discharging the liquid from the tank. A vertically movable cleaning mechanism including a roll cleaning member that contacts the surface of the substrate and a rotation mechanism that rotates the roll cleaning member;
A weight mechanism that generates a variable downward load by its own weight;
A load transmission mechanism that converts the downward load into an upward load and transmits the upward load to the cleaning mechanism;
The load transmitting mechanism, pulleys and, board cleaning equipment you; and a cord extending from the weight mechanism to the cleaning mechanism via the pulley. The substrate cleaning apparatus according to any one of claims 1 to 3, further comprising a lifting mechanism for raising the cleaning mechanism. The substrate cleaning apparatus according to claim 4 , wherein the raising mechanism is an air cylinder.

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