JP2007287831A - Syringe pump and substrate treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology to remove a treatment liquid and particles attaching to the side face of a piston and to keep the lubricity between the piston and a seal member in a syringe pump and a substrate treatment apparatus using the same. <P>SOLUTION: The syringe pump 8 of the substrate treatment apparatus supplies a washing liquid to the side face of the piston 82 in a backward chamber 85 formed in the rear end side of a cylinder 81. Therefore, a resist liquid and particles attaching to the side face of the piston 82 are washed away by the washing liquid and removed from the side face of the piston 82. Part of the washing liquid supplied to the backward chamber 85 attaches to the surface of a first seal member, a second seal member, and the piston 82 and functions as a lubricant. Therefore, the lubricity between the first seal member, the second seal member, and the piston 82 can be maintained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a syringe pump for supplying a processing liquid such as a photoresist liquid, and a substrate processing apparatus for applying the processing liquid to the surface of the substrate while supplying the processing liquid by the syringe pump.

  Conventionally, in the manufacturing process of various substrates such as glass substrates for liquid crystal display devices, semiconductor wafers, film liquid crystal flexible substrates, photomask substrates, color filter substrates, etc., processing solutions such as photoresist solutions have been supplied to the surface of the substrate A substrate processing apparatus is known. Such a substrate processing apparatus includes a pump for feeding a processing liquid. Syringe pumps (piston pumps), bellows pumps, gear pumps, diaphragm pumps, tube pumps, etc. are used as pumps. Among them, syringe pumps are excellent in discharge response and constant flow rate, and are often used in substrate processing equipment. in use.

  A conventional substrate processing apparatus provided with a syringe pump is disclosed in Patent Document 1, for example.

JP-A-2005-246201

  As described in Patent Document 1, the syringe pump has a cylinder and a piston, and feeds the processing liquid in the cylinder downstream by moving the piston back and forth in the cylinder. However, in such a syringe pump, when the piston is retracted (pulled), the treatment liquid adhering to the side surface of the piston may be exposed to the outside of the cylinder together with the piston and hardened. When the piston is advanced (pushed) again, particles generated by the curing of the processing liquid may be mixed into the processing liquid in the cylinder. Although a seal member is provided at the sliding contact portion between the cylinder and the piston, it has been difficult to completely prevent the processing liquid adhering to the side surface of the piston from being exposed to the outside together with the piston.

  Further, in the syringe pump, in order to smoothly move the piston back and forth within the cylinder, and to prevent wear deterioration of the seal member provided between the cylinder and the piston, It is required to always maintain the lubricity between.

  The present invention has been made in view of such circumstances, and in a substrate processing apparatus using a syringe pump and a syringe pump, the processing liquid and particles adhering to the side surface of the piston are removed, and the piston, the seal member, It aims at providing the technique which can maintain the lubricity between.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a syringe pump for feeding a processing liquid, and has a hollow having a suction hole for sucking the processing liquid and a discharge hole for discharging the processing liquid. And the internal space of the cylinder are divided into a first chamber communicating with the suction hole and the discharge hole, and a second chamber formed on the rear side of the cylinder from the first chamber. A partition member having a first through-hole penetrating in the front-rear direction, and a part of the outer wall of the second chamber disposed at the rear end of the cylinder and penetrating in the front-rear direction of the cylinder; A rear end member having two through-holes, and the first through-hole and the second through-hole are inserted into the first chamber, and the rear end is disposed in the first chamber. Outside of the cylinder from the rear end A first seal member that slidably seals between a piston disposed, a drive unit that moves the piston back and forth in the longitudinal direction of the cylinder, and an inner side surface of the first through hole and a side surface of the piston; A second seal member that seals the inner side surface of the second through hole and the side surface of the piston in a slidable manner, and supplies a predetermined liquid to the side surface of the piston inside the second chamber And a liquid discharge means for discharging the predetermined liquid from the second chamber.

  The invention according to claim 2 is the syringe pump according to claim 1, wherein the piston advances and retreats in the front-rear direction of the cylinder without slidingly contacting the inner surface of the cylinder, and the volume of the first chamber is reduced. The treatment liquid is ejected from the ejection holes by changing.

  The invention according to claim 3 is the syringe pump according to claim 1 or 2, wherein the liquid supply means stores the predetermined liquid in the second chamber so that the side surface of the piston is provided. The predetermined liquid is supplied.

  The invention according to claim 4 is the syringe pump according to claim 1 or 2, wherein the liquid supply means directs the predetermined liquid toward a side surface of the piston disposed in the second chamber. It is characterized by discharging.

  The invention according to claim 5 is the syringe pump according to any one of claims 1 to 4, wherein the predetermined liquid is a solvent of the processing liquid or the processing liquid. .

  The invention according to claim 6 is the syringe pump according to any one of claims 1 to 5, wherein a predetermined gas is supplied to a side surface of the piston to which the predetermined liquid is supplied in the second chamber. It further comprises gas supply means for supplying and gas discharge means for discharging the predetermined gas from the second chamber.

  The invention according to claim 7 is the syringe pump according to any one of claims 1 to 6, wherein at least the first seal member and the second seal member among the side surfaces of the piston, The sliding contact portion is a plateau structure surface.

  The invention according to claim 8 is the syringe pump according to claim 7, wherein the load length ratio Rmr (c) defined in JISB0601 of the surface of the plateau structure is 50% of the maximum height roughness Rz. Rmr (c) ≧ 70% at the cutting level c.

  The invention according to claim 9 is the syringe pump according to claim 7 or claim 8, wherein the arithmetic average height Ra and the maximum peak height Rp defined in JISB0601 of the surface of the plateau structure are Ra ≦ 0. It is characterized by being 08 μm and Rp ≦ 0.3 μm.

  An invention according to claim 10 is a substrate processing apparatus for processing a substrate with a processing liquid, wherein the syringe pump according to any one of claims 1 to 9 and the processing liquid discharged from the syringe pump. Supply means for supplying the substrate to the surface of the substrate.

  According to an eleventh aspect of the present invention, there is provided the substrate processing apparatus according to the tenth aspect, wherein the liquid supply unit is configured to set operation timing of the liquid supply unit, and based on the timing set by the setting unit. And a control means for operating the supply means.

  According to the invention described in claims 1 to 11, the syringe pump includes a liquid supply means for supplying a predetermined liquid to the side surface of the piston in the second chamber formed on the rear side of the cylinder, and a second chamber. Liquid discharging means for discharging a predetermined liquid. For this reason, the processing liquid and particles adhering to the side surface of the piston are washed away by the predetermined liquid and removed. The predetermined liquid supplied to the second chamber adheres to the surfaces of the first seal member, the second seal member, and the piston, and functions as a lubricant. Therefore, the lubricity between the first seal member and the second seal member and the piston is maintained.

  In particular, according to the second aspect of the present invention, the piston advances and retreats in the front-rear direction of the cylinder without sliding contact with the inner surface of the cylinder, and the processing liquid is discharged from the discharge hole by changing the volume of the first chamber. Let For this reason, it is not necessary to maintain the inner surface of the cylinder and the outer surface of the piston with high machining accuracy over a long distance. Therefore, the syringe pump can be easily processed, and a syringe pump having a large capacity can be easily manufactured.

  In particular, according to the invention described in claim 3, the liquid supply means supplies the predetermined liquid to the side surface of the piston by storing the predetermined liquid in the second chamber. For this reason, the predetermined liquid is reliably supplied to the side surface of the piston, and the treatment liquid and particles adhering to the side surface of the piston are satisfactorily removed.

  In particular, according to the invention described in claim 4, the liquid supply means discharges the predetermined liquid toward the side surface of the piston disposed in the second chamber. For this reason, the predetermined liquid is directly supplied to the side surface of the piston, and the treatment liquid and particles adhering to the side surface of the piston are satisfactorily removed.

  In particular, according to the invention described in claim 5, the predetermined liquid is a solvent of the processing liquid or the processing liquid. For this reason, even if the predetermined liquid is mixed in the processing liquid in the first chamber, there is no possibility of adversely affecting the processing liquid in the first chamber.

  In particular, according to the invention described in claim 6, gas supply means for supplying a predetermined gas to the side surface of the piston supplied with the predetermined liquid in the second chamber, and gas for discharging the predetermined gas from the second chamber And a discharging means. For this reason, the excess liquid is forcibly discharged to the outside of the cylinder, and the possibility that the excess liquid enters the first chamber from the second chamber is reduced.

  Particularly, according to the seventh aspect of the invention, at least a portion of the side surface of the piston that is in sliding contact with the first seal member and the second seal member is a plateau structure surface. For this reason, the possibility that the side surface of the piston damages the first seal member and the second seal member is reduced, and wear deterioration of the first seal member and the second seal member is prevented. Further, since the predetermined liquid is favorably held on the side surface of the piston, the lubricity between the first seal member and the second seal member and the piston is further improved.

  In particular, according to the invention described in claim 8, the load length ratio Rmr (c) defined in JIS B0601 of the portion that becomes the plateau structure surface of the side surface of the piston is 50% of the maximum height roughness Rz. Rmr (c) ≧ 70% at the cutting level c. That is, the side surface of the piston has a plateau structure characteristic more remarkably. For this reason, wear deterioration of the first seal member and the second seal member is prevented more favorably, and the lubricity between the first seal member and the second seal member and the piston is further improved.

  In particular, according to the ninth aspect of the present invention, the arithmetic average height Ra and the maximum peak height Rp defined in JISB0601 of the portion of the side surface of the piston that becomes the plateau structure surface are Ra ≦ 0.08 μm and Rp ≦ 0.3 μm. For this reason, a peak part is further planarized in the side surface of a piston, and the wear deterioration of a 1st seal member or a 2nd seal member is prevented more favorably.

  In particular, according to the invention described in claim 10, the substrate processing apparatus supplies the syringe pump according to any one of claims 1 to 9 and the processing liquid discharged from the syringe pump to the surface of the substrate. Supply means. For this reason, generation | occurrence | production of a particle can be prevented in the syringe pump which plays an extremely important role in the processing liquid supply operation of the substrate processing apparatus, and the lubricity of the syringe pump can be maintained.

  In particular, according to the invention described in claim 11, the substrate processing apparatus sets the operation timing of the liquid supply means, and the control for operating the liquid supply means based on the timing set by the setting means. Means. For this reason, the liquid supply timing can be set to an optimum timing according to the processing state of the substrate, and a predetermined liquid can be automatically supplied based on the timing.

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

<1. Overall configuration of substrate processing apparatus>
FIG. 1 is a perspective view showing a configuration of a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate processing apparatus 1 uses a rectangular glass substrate (hereinafter simply referred to as “substrate”) 90 for manufacturing a screen panel of a liquid crystal display device as a substrate to be processed, and photolithography that selectively etches the surface of the substrate 90. In the process, it is an apparatus for applying a photoresist liquid (hereinafter simply referred to as “resist liquid”) as a processing liquid to the surface of the substrate 90. As shown in FIG. 1, the substrate processing apparatus 1 mainly includes a main body 2 and a controller 6.

  The main body 2 includes a stage 3 for placing and holding the substrate 90. The stage 3 is composed of an integral stone material having a rectangular parallelepiped shape, and a holding surface 30 processed flat and horizontally is formed on the upper surface thereof. A large number of vacuum suction ports (not shown) are distributed on the holding surface 30. The substrate 90 placed on the holding surface 30 is stably held on the holding surface 30 by being attracted by the suction force from the vacuum suction port.

  A plurality of lift pins LP that can be raised and lowered are disposed on the holding surface 30 at a predetermined interval. A drive unit is connected to the lift pin LP, and when the drive unit is operated, the lift pin LP moves up and down. As a result, the substrate 90 placed on the lift pins LP moves up and down while maintaining a horizontal posture. A pair of running rails 31 are laid in parallel and horizontally on both sides of the holding surface 30 across the area where the substrate 90 is held. The traveling rail 31 is connected to the following bridging portion 4 and plays a role of guiding the movement of the bridging portion 4 in the laying direction of the traveling rail 31.

  A bridging portion 4 is provided above the stage 3. The bridging portion 4 includes a nozzle support portion 40 and elevating mechanisms 43 and 44 that support both ends of the nozzle support portion 40. The nozzle support portion 40 is made of carbon fiber reinforced resin as an aggregate, and is stretched substantially horizontally in a direction perpendicular to the laying direction of the traveling rail 31. A slit nozzle 41 and a gap sensor 42 are attached to the nozzle support portion 40. The slit nozzle 41 discharges the resist solution downward while scanning the surface of the substrate 90, thereby removing the surface of the substrate 90 (more precisely, a region having a predetermined width around the surface of the substrate 90. (Region) has a function of applying a resist solution. The slit nozzle 41 is connected to a supply mechanism 7 (see FIG. 2) described later, and applies a resist solution supplied from the supply mechanism to the surface of the substrate 90. The applied resist solution forms a resist film on the surface of the substrate 90. The gap sensor 42 is attached in the vicinity of the slit nozzle 41. The gap sensor 42 has a function of measuring a distance from a lower entity (the surface of the substrate 90 or the surface of the resist film).

  The elevating mechanisms 43 and 44 are connected to both end portions of the nozzle support portion 40. The elevating mechanisms 43 and 44 have AC servomotors 43a and 44a and a drive unit including a ball screw (not shown). The elevating mechanisms 43 and 44 operate the drive unit to apply elevating driving force to both end portions of the nozzle support unit 44 to move the nozzle support unit 44 up and down while maintaining a horizontal posture. The left and right elevating mechanisms 43 and 44 can also adjust the horizontal posture of the slit nozzle 41 by operating independently. A pair of traveling portions corresponding to the traveling rail 31 is provided at the lower part of the elevating mechanisms 43 and 44. The traveling unit travels along the traveling rail 31 and moves the bridging unit 4 horizontally above the substrate 90.

  In addition, a pair of linear motors 50 and 51 and a pair of linear encoders 52 and 53 are provided outside the traveling rail 31 and the bridge portion 4. The linear motors 50 and 51 include stators 50 a and 51 a fixed to the side surface of the stage 3 and movers 50 b and 51 b fixed to the side of the bridging portion 4. The linear motors 50 and 51 move the bridge portion 4 in the direction along the traveling rail 31 by the driving force generated between the stators 50a and 51a and the movers 50b and 51b. On the other hand, the linear encoders 52 and 53 have a scale portion fixed along the stators 50a and 51a and a detector fixed further outside the movers 50b and 51b. The linear encoders 52 and 53 detect the position of the bridging portion 4 by measuring the relative position of the detector with respect to the scale portion.

  An opening 32 is formed in a part of the region sandwiched between the running rails 31 of the holding surface 30 on the stage 3. A standby pot, a nozzle cleaning mechanism, and a pre-coating mechanism are provided inside the main body 2 below the opening 32. These mechanisms are used in preliminary processes such as a resist liquid supply process, an air bleeding process, and a pre-dispensing process that are performed in advance prior to the resist liquid coating process on the substrate 90.

  The control unit 6 includes an arithmetic unit 60 for processing various data according to a program and a storage unit 61 for storing the program and various data. Specifically, the calculation unit 60 is configured by a CPU and an MPU, and the storage unit 61 is configured by a RAM, a ROM, a magnetic disk device, and the like. The storage unit 61 stores, for example, information related to the timing for supplying the cleaning liquid and the replacement gas into the syringe pump 8 described later. On the front surface of the control unit 6, an operation unit 62 for receiving an operation input from an operator and a display unit 63 for displaying various information are provided. Specifically, the operation unit 62 includes a plurality of switches (including a keyboard and a mouse), and the display unit 63 includes a liquid crystal display and a CRT. The operator can arbitrarily set the timing information stored in the storage unit 61 by operating the operation unit 62, for example. The display unit 63 may be configured by a touch panel display, and the display unit 63 may also be configured to have the function of the operation unit 62.

  FIG. 2 is a sectional side view of the stage 3 and the slit nozzle 41 described above. FIG. 2 also schematically shows an electrical or mechanical connection configuration of each part of the substrate processing apparatus 1. The control unit 6 is electrically connected to the gap sensor 42, the lifting mechanisms 43 and 44, the linear motors 50 and 51, the linear encoders 52 and 53, and the supply mechanism 7. The control unit 6 receives measurement values transmitted from the gap sensor 42 and the linear encoders 52 and 53, and controls operations of the lifting mechanisms 43 and 44, the linear motor 50, and the supply mechanism 7. For example, the control unit 6 adjusts the distance between the substrate 90 and the slit nozzle 41 by controlling the operation of the elevating mechanisms 43 and 44 based on the measurement value received from the gap sensor 42. The control unit 6 performs the scanning operation of the slit nozzle 41 on the stage 3 by controlling the operation of the linear motor 50 based on the measurement values received from the linear encoders 52 and 53. Further, the control unit 6 controls the operation of the supply mechanism 7 to discharge the resist solution from the slit nozzle 41 onto the surface of the substrate 90.

<2. Configuration of supply mechanism>
FIG. 3 is a diagram showing a specific configuration of the supply mechanism 7. As shown in FIG. 3, the supply mechanism 7 includes a trap tank 71, pipes 72 a to 72 h, on-off valves 73 a to 73 d, a pressure adjustment unit 74, a filter 75, and a syringe pump 8. The on-off valves 73a to 73d, the pressure adjusting unit 74, and the drive mechanism 86 of the syringe pump 8 are electrically connected to the control unit 6, and the control unit 6 controls these operations, whereby the slit nozzle 41 is controlled. The resist solution supply operation is realized.

  The trap tank 71 temporarily stores the resist solution supplied from the resist solution supply source 70 via the pipe 72a. When the resist solution is stored in the trap tank 71, bubbles in the resist solution rise to the liquid surface and escape to the upper part of the trap tank 71. And the gaseous component collected on the upper part of the trap tank 71 is discharged | emitted outside via the piping 72b. Thereby, bubbles in the resist solution are removed.

  The syringe pump 8 is a discharge pump for sucking the resist solution stored in the trap tank 71 and discharging the sucked resist solution toward the slit nozzle 41. The syringe pump 8 includes a hollow cylinder 81 and a piston (plunger) 82 that moves forward and backward within the cylinder 81. The inside of the cylinder 81 is partitioned into a front chamber 84 and a rear chamber 85 by a partition member 83, and the resist solution sucked from the trap tank 71 is filled in the front chamber 84. The piston 82 passes through the partition member 83 and is inserted in the front-rear direction of the cylinder 81. The rear end portion of the piston 82 is connected to the drive mechanism 86, and the piston 82 advances and retreats in the front-rear direction of the cylinder 81 by the driving force received from the drive mechanism 86.

  The front chamber 84 of the syringe pump 8 and the trap tank 71 are connected by a pipe 72c. An opening / closing valve 73a is inserted in the middle of the route of the pipe 72c. The front chamber 84 of the syringe pump 8 and the slit nozzle 41 are connected by a pipe 72d. An opening / closing valve 73b is inserted in the middle of the path of the pipe 72d. Therefore, when the on-off valve 73b is closed and the on-off valve 73a is opened and the piston 82 is retracted (pulled), the resist solution stored in the trap tank 71 is sucked into the front chamber 84 through the pipe 72c. The When the on-off valve 73a is closed and the on-off valve 73b is opened to advance (push) the piston 82, the resist solution filled in the front chamber 84 is fed to the slit nozzle 41 via the pipe 72d. The The slit nozzle 41 applies the fed resist solution to the surface of the substrate 90.

  On the other hand, a pipe 72 e is connected to the rear chamber 85 of the cylinder 81. The upstream side of the pipe 72e branches into a pipe 72f and a pipe 72g, and a cleaning liquid supply source 76 for supplying a cleaning liquid is connected to the upstream side of the pipe 72f. Therefore, when the on-off valve 73c provided on the pipe 72f is opened, the cleaning liquid is supplied from the cleaning liquid supply source 76 into the rear chamber 85 through the pipe 72f and the pipe 72e. A replacement gas supply source 77 for supplying replacement gas is connected to the upstream side of the pipe 72g. Therefore, when the on-off valve 73d provided on the pipe 72g is opened, the replacement gas is supplied from the replacement gas supply source 77 into the rear chamber 85 through the pipe 72g and the pipe 72e. The on-off valve 73c and the on-off valve 73d function as switching means for switching the supply of the cleaning liquid and the replacement gas.

  The cleaning liquid and replacement gas supplied into the rear chamber 85 are discharged to the outside of the cylinder via the pipe 72h. In addition, as said washing | cleaning liquid, organic solvents, such as acetone, PEGMEA, PEGME, etc. which are a solvent component of a resist liquid and also have a function as a lubricant are used, for example. Moreover, as said replacement gas, inert gas, such as nitrogen gas, and CDA (clean dry air) are used, for example.

  A pressure adjusting unit 74 is connected to a pipe 72 c that connects the trap tank 71 and the cylinder 81. The pressure adjusting unit 74 maintains the suction pressure of the resist solution sucked from the trap tank 71 to the cylinder 81 below a predetermined value, thereby preventing bubbles from being generated in the resist solution. A filter 75 is inserted in a pipe 72d that connects the syringe pump 8 and the slit nozzle 41. The filter 75 removes impurities (particles, bubbles, etc.) present in the resist solution discharged from the syringe pump 8 and cleans the resist solution.

  FIG. 4 is a diagram showing the configuration of the syringe pump 8 in more detail. The configuration of the syringe pump 8 will be further described with reference to FIG. The cylinder 81 of the syringe pump 8 is made of stainless steel such as SUS and has a substantially cylindrical outer shape. The internal space of the cylinder 81 is partitioned into a front chamber 84 and a rear chamber 85 by a partition member 83. A suction hole 81 a is formed on the side surface of the cylinder 81 facing the front chamber 84. The pipe 72c is connected to the suction hole 81a, and the resist solution sucked from the trap tank 71 (see FIG. 3) is introduced into the front chamber 84 from the suction hole 81a. A discharge hole 81b is formed in the front end portion of the cylinder 81 (the upper surface of the cylinder 81 in FIG. 4). The pipe 72d is connected to the discharge hole 81b, and the resist solution discharged from the cylinder 81 is sent to the pipe 72d through the discharge hole 81b. That is, the front chamber 84 is a space for filling a resist solution as a processing solution.

  A rear end member 87 for sealing the rear end portion of the cylinder 81 is attached to the rear end portion of the cylinder 81 (the bottom surface of the cylinder 81 in FIG. 4). The rear end member 87 forms an outer wall of the rear chamber 85 together with the partition member 83, and the space surrounded by the partition member 83, the rear end member 87, and the side surface of the cylinder 81 is the rear chamber 85. The partition member 83 and the rear end member 87 are formed with through holes 83a and 87a penetrating in the front-rear direction of the cylinder 81, and a piston 82 is inserted into the through holes 83a and 87a.

  The rear end portion of the piston 82 is connected to the drive mechanism 86. The drive mechanism 86 includes a motor 86a, a ball screw 86b, a nut portion 86c, a guide portion 86d, and a connecting member 86e. The drive mechanism 86 rotates the ball screw 86b by the driving force generated by the motor 86a, and moves the nut portion 86c screwed to the ball screw in the front-rear direction of the cylinder 81 along the guide portion 86d. The piston 82 connected to the nut portion 86c via the connecting member 86e moves forward and backward as the nut portion 86c moves.

  A first seal member 83 b is attached to the inner peripheral surface of the through hole 83 a of the partition member 83. The first seal member 83b is made of a resin material having excellent slidability and wear resistance, and slidably seals between the inner peripheral surface of the through hole 83a of the partition member 83 and the outer peripheral surface of the piston 82. . A second seal member 87 b is attached to the inner peripheral surface of the through hole 87 a of the rear end member 87. The second seal member 87b is also made of a resin material having excellent slidability and wear resistance, and slidably seals between the inner peripheral surface of the through hole 87a of the rear end member 87 and the outer peripheral surface of the piston 82. To do. Specifically, a resin material such as PEEK, Ny, POM, UHMW-HDPE, polyethylene terephthalate, or polyimide can be used as the material constituting the seal members 83b and 87b.

  An introduction hole 81 c is formed on the side surface of the cylinder 81 facing the rear chamber 85. The pipe 72e is connected to the introduction hole 81c, and the cleaning liquid supplied from the cleaning liquid supply source 76 and the replacement gas supplied from the replacement gas supply source 77 are introduced into the rear chamber 85 from the introduction hole 81c. The A discharge hole 81d is formed at a position lower than the introduction hole 81c on the opposite side of the side surface of the cylinder 81 facing the rear chamber 85 with the introduction hole 81c and the piston 82 interposed therebetween. The pipe 72h is connected to the discharge hole 81d, and the liquid or gas in the rear chamber 85 is discharged from the discharge hole 81d to the pipe 72h.

  When the cleaning liquid is supplied into the rear chamber 85, the cleaning liquid is stored in the rear chamber 85 and forms a liquid flow in the vicinity of the piston 82 disposed in the rear chamber 85. For this reason, the resist liquid and particles adhering to the side surface of the piston 82 are washed away by the cleaning liquid and removed from the side surface of the piston 82. Therefore, the resist solution adhering to the side surface of the piston 82 is prevented from being exposed and cured behind the rear end member 87. Further, it is possible to prevent particles adhering to the side surface of the piston 82 from entering the front side of the partition member 83 and mixing into the resist solution in the front chamber 84.

  A part of the cleaning liquid supplied into the rear chamber 85 adheres to the surfaces of the first seal member 83b, the second seal member 87b, and the piston 82, and functions as a lubricant. Therefore, the lubricity between the first seal member 83b and the second seal member 87b and the piston 82 is maintained, and the forward / backward movement of the piston 82 is performed smoothly.

  After the cleaning liquid is supplied to the rear chamber 85, when the on-off valve 73c (see FIG. 3) is closed and the on-off valve 73d (see FIG. 3) is opened, the supply of the cleaning liquid is stopped and the replacement gas enters the rear chamber 85. Supplied. When the replacement gas is supplied into the rear chamber 85, the replacement gas forcibly pushes and discharges excess liquid in the rear chamber 85 to the discharge hole 81d side. For this reason, it is possible to prevent excessive cleaning liquid from entering the front side of the partition member 83 and mixing into the resist liquid in the front chamber 84. The side surface of the piston 82 after supply of the replacement gas is in a state where only an appropriate amount of cleaning liquid as a lubricant is thinly attached.

  FIG. 5 is a diagram showing a simplified cross-sectional shape near the side surface of the piston 82. As shown in FIG. 5, the side surface of the piston 82 is a so-called “plateau structure surface” in which a high peak portion is cut to form a flat portion 82 a and a deep valley portion 82 b remains. For this reason, the possibility that the side surface of the piston 82 damages the first seal member 83b and the second seal member 87b is reduced, and wear deterioration of the first seal member 83b and the second seal member 87b is prevented. Further, the cleaning liquid enters the valley portion 82b, whereby the cleaning liquid is favorably held on the side surface of the piston 82. Therefore, the lubricity between the first seal member 83b and the second seal member 87b and the piston 82 is maintained well.

  Specifically, the side surface of the piston 82 has a load length ratio Rmr (c) defined in JISB0601 (corresponding international standard: ISO4287) at a cutting level c of 50% of the maximum height roughness Rz. ) It is desirable that it is processed so that ≧ 70%. Such a side surface of the piston 82 has a characteristic of a plateau structure more remarkably. Therefore, the wear deterioration of the first seal member 83b and the second seal member 87b is prevented better, and the lubricity between the first seal member 83b and the second seal member 87b and the piston 82 is better maintained. .

  The side surface of the piston 82 is processed so that the arithmetic average height Ra and the maximum peak height Rp specified in JISB0601 (corresponding international standard: ISO4287) are Ra ≦ 0.08 μm and Rp ≦ 0.3 μm. If it is, it is more desirable. The side surface of the piston 82 has a plateau structure surface in which a high peak portion is cut more flatly. Therefore, the wear deterioration of the first seal member 83b and the second seal member 87b can be further prevented. Further, if the properties of the side surface of the piston are further limited by using the maximum height roughness Rz and the maximum valley depth Rv specified in JISB0601 (corresponding international standard: ISO4287), the side surface of the piston 82 has Rz ≦ 1. It is desirable that the material is processed so as to satisfy 3 μm and Rv ≦ 1.0 μm.

  Returning to FIG. 4, the piston 82 is not in direct sliding contact with the inner surface of the cylinder 81, but in sliding contact with the inner surface of the through hole 83 a formed in the partition member 83 and the through hole 87 a formed in the rear end member 87. While moving forward and backward. Then, the resist liquid is discharged from the discharge hole 81b by changing the volume of the front chamber 84. For this reason, it is not necessary to maintain the inner surface of the cylinder 81 and the side surface of the piston 82 with high processing accuracy over a long distance. Therefore, the syringe pump 8 can be easily processed, and the syringe pump 8 having a large capacity can be easily manufactured.

<3. Operation of substrate processing apparatus>
Next, the operation when the substrate 90 is processed in the substrate processing apparatus 1 will be described with reference to the above drawings and the flowchart of FIG. In the processing operation described below, the control unit 6 controls the lift pin LP drive unit, gap sensor 42, elevating mechanisms 43 and 44, linear motors 50 and 51, linear encoders 52 and 53, on-off valves 73a to 73d, The process proceeds by controlling the pressure adjustment unit 74, the drive mechanism 86, and the like.

  When processing the substrate 90 in the substrate processing apparatus 1, first, the on-off valve 73d is closed and the on-off valve 73c is opened, and the cleaning liquid is supplied into the rear chamber 85 of the syringe pump 8 (step S1). The cleaning liquid forms a liquid flow in the vicinity of the piston 82 in the rear chamber 85, and the resist liquid and particles adhering to the side surface of the piston 82 are washed away. The resist liquid and particles removed from the side surface of the piston 82 are discharged from the discharge hole 81d together with the cleaning liquid. The supply of the cleaning liquid is continued for a predetermined time set in the storage unit 61 in advance.

  Subsequently, the on-off valve 73c is closed and the on-off valve 73d is opened, and the replacement gas is supplied into the rear chamber 85 of the syringe pump 8 (step S2). The replacement gas forcibly pushes out the liquid in the rear chamber 85 toward the discharge hole 81 d, and discharges excess cleaning liquid from the rear chamber 85. This prevents the cleaning liquid from entering the front side of the partition member 83 and mixing into the resist liquid in the front chamber 84. The side surface of the piston 82 is in a state where only an appropriate amount of cleaning liquid as a lubricant is attached. The supply of the replacement gas is continued for a predetermined time set in the storage unit 61 in advance.

  Thereafter, the substrate 90 is transported by an operator or a predetermined transport mechanism, and the substrate 90 is placed on a plurality of lift pins LP that protrude on the holding surface 30 of the stage 3 and stand by. Then, the plurality of lift pins LP are lowered to place the substrate 90 on the holding surface 30 (step S3). The substrate 90 is attracted to the holding surface 30 by the suction force of the vacuum suction port, and is stably held on the holding surface 30.

  When the substrate 90 is placed on the holding surface 30, the elevating mechanisms 43 and 44 adjust the posture and height of the slit nozzle 41 based on the measurement value of the gap sensor 42 (step S4). On the other hand, in the supply mechanism 7, the on-off valve 73b is closed and the on-off valve 73a is opened. Then, the syringe pump 8 operates the drive mechanism 86 to retract the piston 82, suck the resist solution in the trap tank 71, and fill the front chamber 84 (step S5). At this time, the rear portion of the piston 82 is pulled out to the rear side of the rear end member 87 and is exposed to the outside of the cylinder 81. However, the portion of the side surface of the piston 82 that is exposed to the outside is cleaned in the rear chamber 85, and the resist solution is not attached. Therefore, the resist solution is not exposed to the outside of the cylinder 81 and hardened.

  Thereafter, the linear motors 50 and 51 move the bridging unit 4 based on the measurement values of the linear encoders 52 and 53. In the supply mechanism 7, the on-off valve 73 a is closed and the on-off valve 73 b is opened, and the syringe pump 8 advances the piston 82 by the drive mechanism 86. As a result, the slit nozzle 41 applies a resist solution to the surface of the substrate 90 while scanning over the substrate 90 (step S6). At this time, the front portion of the piston 82 is pushed to the front side of the partition member 83 and enters the front chamber 84. However, the portion of the side surface of the piston 82 that enters the front chamber 84 is cleaned in the rear chamber 85, and no particles are attached. Therefore, particles are not mixed into the resist solution in the front chamber 84.

  When the application of the resist solution to the substrate 90 is completed, the linear motors 50 and 51 return the bridge portion 7 to the standby position. Then, the substrate 90 is pulled away from the holding surface 30 by raising the plurality of lift pins LP. Thereafter, the substrate 90 is removed from the lift pins LP by the operator or a predetermined transport mechanism, and is carried out of the substrate processing apparatus 1 (step S7). Thus, the processing of the substrate 90 in the substrate processing apparatus 1 is completed.

  As described above, the syringe pump 8 of the substrate processing apparatus 1 supplies the cleaning liquid to the side surface of the piston 82 in the rear chamber 85 formed on the rear side of the cylinder 81. For this reason, the resist solution and particles adhering to the side surface of the piston 82 are washed away by the cleaning solution and removed from the side surface of the piston 82. Therefore, the resist solution adhering to the side surface of the piston 82 is prevented from being exposed and cured behind the rear end member 87. Further, it is possible to prevent particles adhering to the side surface of the piston 82 from entering the front side of the partition member 83 and mixing into the resist solution in the front chamber 84.

  A part of the cleaning liquid supplied into the rear chamber 85 adheres to the surfaces of the first seal member 83b, the second seal member 87b, and the piston 82, and functions as a lubricant. Therefore, the lubricity between the first seal member 83b and the second seal member 87b and the piston 82 is maintained, and the forward / backward movement of the piston 82 is performed smoothly.

  The syringe pump 8 advances and retreats while sliding in contact with the inner surfaces of the through holes 83a and 87a formed in the partition member 83 and the rear end member 87 in the cylinder 81, and changes the volume of the front chamber 84 to change the resist solution. Is discharged from the discharge hole 81b. For this reason, the inner surface of the cylinder 81 and the piston 82 are not in direct sliding contact, and it is not necessary to maintain the inner surface of the cylinder 81 and the side surface of the piston 82 with high machining accuracy over a long distance. Therefore, the syringe pump 8 can be easily processed, and the syringe pump 8 having a large capacity can be easily manufactured.

  The syringe pump 8 forms a liquid flow in the vicinity of the piston 82 disposed in the rear chamber 85 while storing the cleaning liquid in the rear chamber 85. For this reason, the cleaning liquid is reliably supplied to the side surface of the piston 82, and the resist solution and particles adhering to the side surface of the piston 82 are removed well.

  The syringe pump 8 uses a liquid that is a solvent component of the resist liquid as a cleaning liquid. For this reason, even if the cleaning liquid is mixed into the resist solution in the front chamber 84, there is no possibility of adversely affecting the resist solution in the front chamber 84.

  In addition, the replacement gas is supplied into the rear chamber 85 of the syringe pump 8 after the cleaning liquid is supplied. For this reason, the excessive cleaning liquid is forcibly discharged to the outside of the cylinder 81, and the possibility that the excessive cleaning liquid enters the front of the partition member 83 is reduced.

  Further, the side surface of the piston 82 is processed so as to be a plateau structure surface. For this reason, the possibility that the side surface of the piston 82 damages the first seal member 83b and the second seal member 87b is reduced, and wear deterioration of the first seal member 83b and the second seal member 87b is prevented. Further, since the cleaning liquid is satisfactorily held on the side surface of the piston 82, the lubricity between the first seal member 83b and the second seal member 87b and the piston 82 is maintained well.

<4. Modification>
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to said example. For example, the syringe pump 8 may be configured as shown in FIG. In the syringe pump 8 of FIG. 7, a spray part 88 is attached to the introduction hole 81 c for introducing the cleaning liquid into the rear chamber 85. The spray part 88 is directed to the side surface of the piston 82 in the rear chamber 85. For this reason, the cleaning liquid supplied from the cleaning liquid supply source 76 is discharged in the form of a mist toward the side surface of the piston 82 in the rear chamber 85. As a result, the cleaning liquid is directly supplied to the side surface of the piston 82, and the resist solution and particles adhering to the side surface of the piston 82 are removed well.

  In the above example, the liquid that is the solvent component of the resist solution is used as the cleaning solution. However, the resist solution itself may be used as the cleaning solution. In this way, even if the cleaning liquid is mixed into the resist solution in the front chamber 84, the component composition ratio of the resist solution in the front chamber 84 does not change.

  In the above example, the cleaning liquid is supplied (Step S1) and the replacement gas is supplied (Step S2) when the processing of one substrate 90 is started. It can be changed according to. For example, the cleaning liquid and the replacement gas may be supplied every time one lot or a predetermined number of substrates 90 are processed. In this way, the consumption of the cleaning liquid and the replacement gas is saved by supplying the cleaning liquid and the replacement gas at a limited timing.

  In the above example, the entire side surface of the piston 82 is processed so as to have a plateau structure surface. However, at least a portion of the side surface of the piston 82 that is in sliding contact with the first seal member 83b and the second seal member 87b is plateau. What is necessary is just to be processed so that it may become a structure surface.

It is the perspective view which showed the structure of the substrate processing apparatus which concerns on one Embodiment of this invention. It is a sectional side view of a stage and a slit nozzle. It is the figure which showed the structure of the supply mechanism. It is the figure which showed the structure of the syringe pump in detail. It is the figure which simplified and showed the cross-sectional shape of the side surface vicinity of a piston. 3 is a flowchart showing a flow of substrate processing in the substrate processing apparatus 1. It is the figure which showed the structure of the syringe pump which concerns on a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 2 Main body part 3 Stage 4 Bridging part 6 Control part 7 Supply mechanism 8 Syringe pump 30 Holding surface 41 Slit nozzle 61 Memory | storage part 62 Operation part 71 Trap tank 73a-73d Open / close valve 76 Cleaning liquid supply source 77 Replacement gas supply source 81 Cylinder 81a Suction hole 81b Discharge hole 81c Inlet hole 81d Discharge hole 82 Piston 83 Partition member 83a, 87a Through hole 83b, 87b Seal member 84 Front chamber 85 Rear chamber 86 Drive mechanism 87 Rear end member 88 Spray part 90 Substrate

Claims (11)

A syringe pump for feeding the treatment liquid,
A hollow cylinder having a suction hole for sucking the processing liquid and a discharge hole for discharging the processing liquid;
The internal space of the cylinder is partitioned into a first chamber communicating with the suction hole and the discharge hole and a second chamber formed on the rear side of the cylinder from the first chamber, and penetrates in the front-rear direction of the cylinder. A partition member having a first through-hole,
A rear end member disposed at a rear end portion of the cylinder and constituting a part of the outer wall of the second chamber, and having a second through-hole penetrating in the front-rear direction of the cylinder;
The first through hole and the second through hole are inserted into the first chamber, and the rear end of the first through hole and the second through hole are arranged outside the cylinder from the rear end of the cylinder. A piston to be
A drive unit for moving the piston back and forth in the longitudinal direction of the cylinder;
A first seal member that seals between an inner surface of the first through-hole and a side surface of the piston in a slidable manner;
A second seal member that seals between an inner side surface of the second through hole and a side surface of the piston in a slidable manner;
Liquid supply means for supplying a predetermined liquid to the side surface of the piston inside the second chamber;
Liquid discharging means for discharging the predetermined liquid from the second chamber;
A syringe pump characterized by comprising: The syringe pump according to claim 1,
The piston moves forward and backward in the front-rear direction of the cylinder without sliding contact with the inner surface of the cylinder, and discharges the processing liquid from the discharge hole by changing the volume of the first chamber. pump. The syringe pump according to claim 1 or 2,
The syringe pump characterized in that the liquid supply means supplies the predetermined liquid to a side surface of the piston by storing the predetermined liquid in the second chamber. The syringe pump according to claim 1 or 2,
The syringe pump characterized in that the liquid supply means discharges the predetermined liquid toward a side surface of the piston disposed in the second chamber. A syringe pump according to any one of claims 1 to 4, wherein
The syringe pump, wherein the predetermined liquid is a solvent of the processing liquid or the processing liquid. A syringe pump according to any one of claims 1 to 5, wherein
Gas supply means for supplying a predetermined gas to a side surface of the piston to which the predetermined liquid is supplied in the second chamber;
Gas discharge means for discharging the predetermined gas from the second chamber;
A syringe pump characterized by further comprising: The syringe pump according to any one of claims 1 to 6,
Of the side surface of the piston, at least a portion in sliding contact with the first seal member and the second seal member is a plateau structure surface. The syringe pump according to claim 7,
A syringe pump characterized in that a load length ratio Rmr (c) defined in JISB0601 on the surface of the plateau structure is Rmr (c) ≧ 70% at a cutting level c of 50% of the maximum height roughness Rz . The syringe pump according to claim 7 or claim 8,
The syringe pump characterized in that the arithmetic average height Ra and the maximum peak height Rp defined in JISB0601 on the surface of the plateau structure are Ra ≦ 0.08 μm and Rp ≦ 0.3 μm. A substrate processing apparatus for processing a substrate with a processing liquid,
A syringe pump according to any one of claims 1 to 9,
Supply means for supplying the processing liquid discharged from the syringe pump to the surface of the substrate;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 10, comprising:
Setting means for setting the operation timing of the liquid supply means;
Control means for operating the liquid supply means based on the timing set by the setting means;
A substrate processing apparatus, further comprising:

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