JP2018143942A - Coating device and coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress generation of coating unevenness when a coating liquid is discharged to an upper surface of a substrate from above a coating stage to coat and then the substrate is conveyed to an outlet stage.SOLUTION: A coating device includes: a conveying part for holding and conveying a substrate; a nozzle which discharges a coating liquid and coats an upper surface of the conveyed substrate with the coating liquid; a coating stage which is arranged on a lower position of the nozzle, and floats the substrate in a horizontal posture by jetting first gas to a lower surface of the conveyed substrate; an outlet stage which is arranged apart from the coating stage on a downstream side of the coating stage in a conveying direction for conveying the substrate, and floats the substrate in the horizontal posture by jetting second gas to the lower surface of the substrate conveyed from the coating stage; and a temperature control mechanism which controls a temperature of an atmosphere interposed between a gap region interposed between the coating stage and the outlet stage and the lower surface of the substrate which is conveyed by passing above the gap region so that the temperature is brought close to temperatures of the first gas and the second gas.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a coating apparatus and a coating method for applying a coating liquid onto an upper surface of a substrate while being transported in a horizontal direction in a state of being floated from a stage. The above substrates include semiconductor substrates, photomask substrates, liquid crystal display substrates, organic EL display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, optical disks. Includes magnetic disk substrates.

  2. Description of the Related Art In manufacturing processes for electronic components such as semiconductor devices and liquid crystal display devices, a coating apparatus that discharges a coating liquid onto the upper surface of a substrate and applies it onto the upper surface of the substrate is used. For example, in the coating apparatus described in Patent Document 1, the gas is blown onto the lower surface of the substrate and the substrate is transported from the stage while the substrate is lifted from the stage. The coating liquid is applied to almost the entire surface of the substrate by discharging from the outlet onto the surface of the substrate.

Japanese Patent No. 5346663

  In the apparatus described in Patent Document 1, the coating process is performed by floating the substrate by a coating stage disposed below the slit nozzle. And the board | substrate with which the coating liquid was apply | coated and the coating film was formed is conveyed to the exit levitation | floating stage arrange | positioned in the downstream of the application | coating stage, floating. As described above, the substrate carrying the coating liquid is conveyed while being floated by the coating stage and the outlet floating stage.

  In the coating stage and the exit levitation stage, the compressed air is blown to the lower surface of the substrate to lift the substrate, and the compressed air atmosphere (hereinafter referred to as “coating atmosphere”) is sandwiched between the lower surface of the substrate and the coating stage. And an atmosphere of compressed air (hereinafter referred to as “exit atmosphere”) is also formed in a region sandwiched between the lower surface of the substrate and the exit levitation stage. On the other hand, it is difficult to bring the coating stage and the outlet floating stage into close contact with each other in the substrate transport direction, and a gap of about 1 mm is generated. For this reason, another atmosphere (hereinafter referred to as “boundary atmosphere”) is formed between the coating atmosphere and the outlet atmosphere.

  In the conventional apparatus, no special consideration is given to the boundary atmosphere, and temperature differences may occur between the coating atmosphere and the boundary atmosphere and between the boundary atmosphere and the outlet atmosphere. As a result, coating unevenness due to temperature may occur in the coating film on the substrate. In particular, when transport of the substrate is temporarily stopped in a state where a part of the lower surface of the substrate having the coating film is located above the gap, the temperature of the substrate in the part that contacts the boundary atmosphere during the stop Unlike this part, the coating unevenness in the part becomes remarkable.

  The present invention has been made in view of the above problems, and uneven coating occurs when the substrate is transported to the outlet stage after being applied by discharging the coating liquid from above the coating stage toward the upper surface of the substrate. An object of the present invention is to provide a coating technique capable of performing high-quality coating processing while suppressing the above-described problem.

  One aspect of the present invention is a coating apparatus, which is disposed at a position below a nozzle, a transport unit that holds and transports a substrate, a nozzle that discharges and coats a coating liquid on the top surface of the transported substrate, A coating stage that floats the substrate in a horizontal position by jetting the first gas toward the lower surface of the substrate to be transported, and a space away from the coating stage downstream of the coating stage in the transport direction in which the substrate is transported. An exit stage that floats the substrate in a horizontal position by ejecting the second gas toward the lower surface of the substrate transported from the coating stage, a gap region sandwiched between the coating stage and the outlet stage, and an upper portion of the gap region And a temperature control mechanism that controls the temperature of the atmosphere sandwiched between the lower surface of the substrate that is passed and conveyed so as to approach the temperatures of the first gas and the second gas.

  According to another aspect of the present invention, there is provided a coating stage that floats the substrate in a horizontal posture by ejecting a first gas toward the bottom surface of the substrate, and a second heading toward the bottom surface of the substrate at a position spaced from the coating stage. A coating method in which a coating liquid is ejected from above a coating stage toward an upper surface of a substrate while being transported in the order of an outlet stage that levitates the substrate in a horizontal posture by jetting a gas, and the coating liquid The temperature of the atmosphere sandwiched between the lower surface of the substrate that is transported over the gap area and the gap area when the substrate coated with is positioned above the gap area sandwiched between the coating stage and the exit stage. Control is performed so as to approach the temperatures of the first gas and the second gas.

  In the invention configured as described above, the first gas is ejected from the coating stage to form the first gas atmosphere, that is, the coating atmosphere, between the lower surface of the substrate and the second gas is ejected from the outlet stage. Thus, an atmosphere of the second gas, that is, an outlet atmosphere is formed between the lower surface of the substrate. Further, since the coating stage and the outlet stage are spaced apart from each other, a gap region is formed between them, and an atmosphere sandwiched between the gap region and the lower surface of the substrate is formed. This atmosphere is a boundary atmosphere that serves as a boundary between the coating atmosphere and the outlet atmosphere. When the temperature of the boundary atmosphere differs from the temperatures of the first gas and the second gas and a large temperature difference occurs, the coating is applied to the substrate. The above temperature difference adversely affects the quality of the coating solution. However, in the present invention, since the temperature of the boundary atmosphere is brought close to the temperatures of the first gas and the second gas, the occurrence of coating unevenness due to the temperature difference is suppressed.

  As described above, the temperature of the boundary atmosphere sandwiched between the gap region sandwiched between the coating stage and the outlet stage and the lower surface of the substrate transported through the gap region is the temperature of the first gas and the second gas. Therefore, the coating process can be performed satisfactorily while suppressing uneven coating.

It is a figure which shows typically the whole structure of 1st Embodiment of the coating device concerning this invention. It is the top view which looked at the coating device from the perpendicular upper direction. It is the top view which removed the application | coating mechanism from FIG. It is the sectional view on the AA line of FIG. It is a figure which shows the structure of a floating stage part and a floating control mechanism. It is a figure which shows typically the positional relationship of each part of the apparatus in the application | coating process. It is a figure which shows 2nd Embodiment of the coating device concerning this invention. It is a figure which shows 3rd Embodiment of the coating device concerning this invention. It is a figure which shows 4th Embodiment of the coating device concerning this invention.

  FIG. 1 is a diagram schematically showing an overall configuration of a first embodiment of a coating apparatus according to the present invention. The coating apparatus 1 is a slit coater that applies a coating solution to the upper surface Wf of the substrate W that is transported in a horizontal posture from the left hand side to the right hand side in FIG. In the following drawings, in order to clarify the arrangement relationship of each part of the apparatus, the transport direction of the substrate W is referred to as “X direction”, and the horizontal direction from the left hand side to the right hand side in FIG. 1 is referred to as “+ X direction”. The reverse direction is referred to as the “−X direction”. Further, among the horizontal direction Y orthogonal to the X direction, the front side of the apparatus is referred to as “−Y direction” and the back side of the apparatus is referred to as “+ Y direction”. Further, the upward direction and the downward direction in the vertical direction Z are referred to as “+ Z direction” and “−Z direction”, respectively.

  First, the outline of the configuration and operation of the coating apparatus 1 will be described with reference to FIG. 1, and then the detailed structure of each part will be described. Note that the basic configuration and operation principle of the coating apparatus 1 are the same as those described in Japanese Patent No. 5346663 (Patent Document 1) previously disclosed by the applicant of the present application. Therefore, in the present specification, among the configurations of the coating apparatus 1, configurations similar to those described in these known documents can be applied, and structures can be easily understood from the descriptions of these documents. Detailed description will be omitted, and the characteristic part of this embodiment will be mainly described.

  In the coating apparatus 1, the input conveyor 100, the input transfer unit 2, the floating stage unit 3, the output transfer unit 4, and the output conveyor 110 are arranged close to each other in this order along the transport direction Dt (+ X direction) of the substrate W. Thus, as will be described in detail below, a transport path for the substrate W extending in a substantially horizontal direction is formed. In the following description, when the positional relationship is shown in association with the transport direction Dt of the substrate W, “upstream side in the transport direction Dt of the substrate W” is simply referred to as “upstream side”, and “downstream in the transport direction Dt of the substrate W”. "Side" may be simply abbreviated as "Downstream". In this example, the (−X) side relatively corresponds to “upstream side” and the (+ X) side corresponds to “downstream side” when viewed from a certain reference position.

  The substrate W to be processed is carried into the input conveyor 100 from the left hand side of FIG. The input conveyor 100 includes a roller conveyor 101 and a rotation driving mechanism 102 that rotationally drives the roller conveyor 101, and the substrate W is transported in a horizontal posture downstream, that is, in the (+ X) direction by the rotation of the roller conveyor 101. The input transfer unit 2 includes a roller conveyor 21 and a rotation / elevation drive mechanism 22 having a function of rotationally driving the roller conveyor 21 and a function of elevating and lowering the roller conveyor 21. As the roller conveyor 21 rotates, the substrate W is further transported in the (+ X) direction. Moreover, the vertical direction position of the board | substrate W is changed because the roller conveyor 21 raises / lowers. The substrate W is transferred from the input conveyor 100 to the floating stage unit 3 by the input transfer unit 2 configured as described above.

  The levitation stage unit 3 includes a flat stage divided into three along the substrate transport direction Dt. That is, the levitation stage unit 3 includes an inlet levitation stage 31, a coating stage 32, and an outlet levitation stage 33, and the upper surfaces of these stages are part of the same plane. The upper surfaces of the inlet levitation stage 31 and the outlet levitation stage 33 are provided with a large number of ejection holes for ejecting compressed air supplied from the levitation control mechanism 35 in a matrix, and the buoyancy imparted from the ejected airflow The substrate W rises. Thus, the lower surface Wb of the substrate W is supported in a horizontal posture in a state of being separated from the upper surface of the stage. The distance between the lower surface Wb of the substrate W and the upper surface of the stage, that is, the flying height can be, for example, 10 micrometers to 500 micrometers.

  On the other hand, on the upper surface of the coating stage 32, ejection holes for ejecting compressed air and suction holes for sucking air between the lower surface Wb of the substrate W and the upper surface of the stage are alternately arranged. The distance between the lower surface Wb of the substrate W and the upper surface of the coating stage 32 is precisely controlled by the levitation control mechanism 35 controlling the amount of compressed air ejected from the ejection holes and the amount of suction from the suction holes. Thereby, the vertical position of the upper surface Wf of the substrate W passing over the coating stage 32 is controlled to a specified value. As a specific configuration of the levitation stage unit 3, for example, the one described in Japanese Patent No. 5346663 (Patent Document 1) can be applied.

  As shown in FIG. 1, the outlet floating stage 33 is arranged in parallel with the coating stage 32 so as to be separated from each other in the transport direction (+ X), and a gap region CL is formed between them. A gas supply pipe 6 is disposed vertically below the gap region CL, and receives compressed air supplied from the levitation control mechanism 35 and jets compressed air into the gap region CL. This suppresses the occurrence of coating unevenness. This point will be described in detail later together with the configuration description of the levitation control mechanism 35.

  The entrance levitation stage 31 is provided with lift pins not shown in the drawing, and the levitation stage portion 3 is provided with a lift pin drive mechanism 34 for raising and lowering the lift pins.

  The substrate W carried into the levitation stage unit 3 via the input transfer unit 2 is given a propulsive force in the (+ X) direction by the rotation of the roller conveyor 21 and is conveyed onto the inlet levitation stage 31. The inlet floating stage 31, the coating stage 32, and the outlet floating stage 33 support the substrate W in a floating state, but do not have a function of moving the substrate W in the horizontal direction. The transport of the substrate W in the levitation stage unit 3 is performed by the substrate transport unit 5 disposed below the entrance levitation stage 31, the coating stage 32, and the exit levitation stage 33.

  The substrate transport unit 5 includes a chuck mechanism 51 that supports the substrate W from below by partially abutting on the peripheral edge of the lower surface of the substrate W, and an adsorption member (see FIGS. 3, 4, and 6). A suction / running control mechanism 52 having a function of sucking and holding the substrate W by sucking a suction pad (not shown) provided in the reference numeral 513) and a function of reciprocating the chuck mechanism 51 in the X direction. I have. In a state where the chuck mechanism 51 holds the substrate W, the lower surface Wb of the substrate W is positioned higher than the upper surface of each stage of the levitation stage unit 3. Therefore, the substrate W maintains the horizontal posture as a whole by the buoyancy applied from the levitation stage unit 3 while the peripheral portion is sucked and held by the chuck mechanism 51.

  The chuck mechanism 51 holds the substrate W carried into the floating stage unit 3 from the input transfer unit 2, and the substrate W moves above the entrance floating stage 31 by moving the chuck mechanism 51 in the (+ X) direction in this state. From above the coating stage 32 and then conveyed above the outlet floating stage 33. The transported substrate W is transferred to the output transfer unit 4 disposed on the (+ X) side of the outlet floating stage 33.

  The output transfer unit 4 includes a roller conveyor 41, and a rotation / lift drive mechanism 42 having a function of rotating and driving the roller conveyor 41. By rotating the roller conveyor 41, a propulsive force in the (+ X) direction is applied to the substrate W, and the substrate W is further transported along the transport direction Dt. Further, the vertical position of the substrate W is changed by moving the roller conveyor 41 up and down. Then, the output transfer unit 4 transfers the substrate W to the output conveyor 110 from above the outlet floating stage 33.

  The output conveyor 110 includes a roller conveyor 111 and a rotation driving mechanism 112 that rotates and drives the substrate. The substrate W is further transported in the (+ X) direction by the rotation of the roller conveyor 111, and finally the outside of the coating apparatus 1. To be paid out. The input conveyor 100 and the output conveyor 110 may be provided as part of the configuration of the coating apparatus 1, but may be separate from the coating apparatus 1. Further, for example, a separate unit substrate dispensing mechanism provided on the upstream side of the coating apparatus 1 may be used as the input conveyor 100. Further, a substrate receiving mechanism of another unit provided on the downstream side of the coating apparatus 1 may be used as the output conveyor 110.

  A coating mechanism 7 for coating the coating liquid on the upper surface Wf of the substrate W is disposed on the transport path of the substrate W transported in this manner. The coating mechanism 7 includes a nozzle 71 that is a slit nozzle and a maintenance unit 75 for performing maintenance on the nozzle 71. A coating liquid is supplied to the nozzle 71 from a coating liquid supply unit (not shown), and the coating liquid is discharged from a discharge port that opens downward in the lower part of the nozzle.

  The nozzle 71 can be moved and positioned in the X direction and the Z direction by a positioning mechanism 73. The positioning mechanism 73 positions the nozzle 71 at a coating position (position indicated by a dotted line) above the coating stage 32. The coating liquid is discharged from the nozzle positioned at the coating position, and is applied to the substrate W transported between the coating stage 32. Thus, the coating liquid is applied to the substrate W.

  The maintenance unit 75 includes a bat 751 that stores cleaning liquid for cleaning the nozzle 71, a preliminary discharge roller 752, a nozzle cleaner 753, and a maintenance control mechanism 754 that controls operations of the preliminary discharge roller 752 and the nozzle cleaner 753. I have. As a specific configuration of the maintenance unit 75, for example, a configuration described in JP 2010-240550 A can be applied.

  At the position where the nozzle 71 is above the preliminary discharge roller 752 and the discharge port faces the upper surface of the preliminary discharge roller 752 (preliminary discharge position), the coating liquid is discharged from the discharge port of the nozzle 71 toward the upper surface of the preliminary discharge roller 752. The The nozzle 71 is positioned at the preliminary discharge position prior to being positioned at the application position, and performs a preliminary discharge process by discharging a predetermined amount of coating liquid from the discharge port. Thus, by causing the nozzle 71 before moving to the application position to perform the preliminary discharge process, the discharge of the coating liquid at the application position can be stabilized from the initial stage.

  The maintenance control mechanism 754 rotates the preliminary discharge roller 752 so that the discharged coating liquid is mixed with the cleaning liquid stored in the bat 751 and collected. Further, in a state where the nozzle 71 is located above the nozzle cleaner 753 (first cleaning position), the nozzle cleaner 753 moves in the Y direction while discharging the cleaning liquid, thereby adhering to the discharge port of the nozzle 71 and its surroundings. The coating solution is washed away.

  Further, the positioning mechanism 73 can position the nozzle 71 at a position (standby position) below the first cleaning position and where the lower end of the nozzle is accommodated in the bat 751. When the coating process using the nozzle 71 is not executed, the nozzle 71 is positioned at this standby position. Although illustration is omitted, a standby pod for preventing the coating liquid from drying at the discharge port may be arranged for the nozzle 71 positioned at the standby position.

  In addition, the coating apparatus 1 is provided with a control unit 9 for controlling the operation of each part of the apparatus. The control unit 9 is responsible for exchanging information with a storage means for storing a predetermined control program and various data, a calculation means such as a CPU for causing each part of the apparatus to execute a predetermined operation by executing this control program, and a user and an external device. Interface means are provided.

  FIG. 2 is a plan view of the coating apparatus as viewed from above. FIG. 3 is a plan view in which the coating mechanism is removed from FIG. 4 is a cross-sectional view taken along line AA in FIG. Hereinafter, a specific mechanical configuration of the coating apparatus 1 will be described with reference to these drawings. With regard to some mechanisms, a more detailed structure can be understood by referring to the description of Japanese Patent No. 5346663 (Patent Document 1). In FIGS. 2 and 3, the description of the rollers of the input conveyor 100 and the like is omitted.

  The nozzle unit 70 of the coating mechanism 7 has a bridging structure as shown in FIGS. Specifically, the nozzle unit 70 is composed of a pair of column members 732 and 733 erected upward from the base 10 at both ends in the Y direction of the beam member 731 extending in the Y direction above the floating stage unit 3. It has a supported structure. An elevating mechanism 734 configured by, for example, a ball screw mechanism is attached to the column member 732, and the (+ Y) side end portion of the beam member 731 is supported by the elevating mechanism 734 so as to be movable up and down. Further, an elevating mechanism 735 configured by, for example, a ball screw mechanism is attached to the column member 733, and the (−Y) side end portion of the beam member 731 is supported by the elevating mechanism 735 so as to be movable up and down. The elevating mechanisms 734 and 735 are interlocked according to a control command from the control unit 9, so that the beam member 731 moves in the vertical direction (Z direction) while maintaining a horizontal posture.

  A nozzle 71 is attached to the lower center of the beam member 731 with the discharge port 711 facing downward. Therefore, movement of the nozzle 71 in the Z direction is realized by operating the lifting mechanisms 734 and 735.

  The column members 732 and 733 are configured to be movable in the X direction on the base 10. Specifically, a pair of travel guides 81 </ b> L and 81 </ b> R extending in the X direction are attached to the upper surfaces of the (+ Y) side and (−Y) side end portions of the base 10, and the column member 732. Is engaged with the traveling guide 81L on the (+ Y) side through a slider 736 attached to the lower part thereof. The slider 736 is movable in the X direction along the traveling guide 81L. Similarly, the column member 733 is engaged with the travel guide 81R on the (−Y) side via a slider 737 attached to the lower portion thereof, and is movable in the X direction.

  The column members 732 and 733 are moved in the X direction by the linear motors 82L and 82R. Specifically, the magnet modules of the linear motors 82L and 82R are extended along the X direction on the base 10 as stators, and the coil modules are attached to the lower portions of the column members 732 and 733 as movers. When the linear motors 82L and 82R are operated in accordance with a control command from the control unit 9, the entire nozzle unit 70 moves along the X direction. Thereby, the movement of the nozzle 71 in the X direction is realized. The X-direction positions of the column members 732 and 733 can be detected by linear scales 83L and 83R provided in the vicinity of the sliders 736 and 737.

  Thus, the nozzle 71 moves in the Z direction by operating the elevating mechanisms 734 and 735, and the nozzle 71 moves in the X direction by operating the linear motors 82L and 82R. That is, when the control unit 9 controls these mechanisms, the nozzle 71 is positioned at each stop position (application position, preliminary discharge position, etc.). Accordingly, the elevating mechanisms 734 and 735, the linear motors 82L and 82R, the control unit 9 for controlling these, and the like function as the positioning mechanism 73 in FIG.

  The maintenance unit 75 has a structure in which a preliminary discharge roller 752 and a nozzle cleaner 753 are accommodated in a butt 751. Although not shown, the maintenance unit 75 is provided with a maintenance control mechanism 754 for driving the preliminary discharge roller 752 and the nozzle cleaner 753. The bat 751 is supported by a beam member 761 extending in the Y direction, and both ends of the beam member 761 are supported by a pair of column members 762 and 763. The pair of column members 762 and 763 are attached to both ends of the plate 764 extending in the Y direction in the Y direction.

  A pair of travel guides 84 </ b> L and 84 </ b> R extend in the X direction on the base 10 below both ends in the Y direction of the plate 764. Both ends of the plate 764 in the Y direction are engaged with the travel guides 84L and 84R via sliders 766 and 767, respectively. For this reason, the maintenance unit 75 is movable in the X direction along the travel guides 84L and 84R. A linear motor 85 is provided below the (−Y) direction end of the plate 764. The linear motor 85 may be provided below the (+ Y) direction end of the plate 764, or may be provided below the both ends of the Y direction.

  In the linear motor 85, a magnet module is extended as a stator on the base 10 along the X direction, and a coil module is attached to the maintenance unit 75 as a mover. By operating the linear motor 85 according to a control command from the control unit 9, the entire maintenance unit 75 moves along the X direction. The position of the maintenance unit 75 in the X direction can be detected by a linear scale 86 provided in the vicinity of the sliders 766 and 767.

  Next, the structure of the chuck mechanism 51 will be described with reference to FIGS. The chuck mechanism 51 includes a pair of chucks 51L and 51R that have a symmetrical shape with respect to the XZ plane and are spaced apart in the Y direction. Of these, the chuck 51L disposed on the (+ Y) side is supported by the traveling guide 87L extending in the X direction on the base 10 so as to be able to travel in the X direction. Specifically, the chuck 51L includes a base portion 512 having two horizontal plate portions provided at different positions in the X direction and a connection portion that connects these plate portions. Sliders 511 are respectively provided below the two plate portions of the base portion 512, and the base portion 512 can travel in the X direction along the travel guide 87L by engaging the slider 511 with the travel guide 87L. ing.

  At the upper part of the two plate parts of the base part 512, suction members 513 and 513 are provided that are provided with suction pads (not shown) extending upward and not shown. When the base portion 512 moves in the X direction along the travel guide 87L, the two adsorbing members 513 and 513 move in the X direction integrally therewith. The two plate portions of the base portion 512 may be separated from each other, and the plate portions may be structured to function as an integral base portion by moving while maintaining a certain distance in the X direction. If this distance is set according to the length of the substrate, it is possible to deal with substrates of various lengths.

  The chuck 51L is movable in the X direction by a linear motor 88L. That is, the magnet module of the linear motor 88L is extended as a stator on the base 10 in the X direction, and the coil module is attached as a mover to the lower part of the chuck 51L. The linear motor 88L is actuated in accordance with a control command from the control unit 9, whereby the chuck 51L moves along the X direction. The position of the chuck 51L in the X direction can be detected by the linear scale 89L.

  Similarly, the chuck 51 </ b> R provided on the (−Y) side includes a base portion 512 having two plate portions and a connection portion, and suction members 513 and 513. However, the shape is symmetrical to the chuck 51L with respect to the XZ plane. Each plate portion is engaged with the travel guide 87R by a slider 511. Further, the chuck 51R is movable in the X direction by a linear motor 88R. That is, the magnet module of the linear motor 88R is extended as a stator on the base 10 in the X direction, and the coil module is attached as a mover to the lower part of the chuck 51R. The linear motor 88R is actuated according to a control command from the control unit 9, whereby the chuck 51R moves along the X direction. The X-direction position of the chuck 51R can be detected by the linear scale 89R.

  The control unit 9 controls these positions so that the chucks 51L and 51R are always at the same position in the X direction. As a result, the pair of chucks 51L and 51R apparently move as an integrated chuck mechanism 51. Compared with the case where the chucks 51L and 51R are mechanically coupled, interference between the chuck mechanism 51 and the floating stage unit 3 can be easily avoided.

  As shown in FIG. 3, the four adsorption members 513 are arranged corresponding to the four corners of the substrate W to be held. That is, the two suction members 513 and 513 of the chuck 51L hold the upstream end and the downstream end in the transport direction Dt, respectively, on the (+ Y) side periphery of the substrate W. On the other hand, the two adsorbing members 513 and 513 of the chuck 51R respectively hold the upstream end and the downstream end in the transport direction Dt on the (−Y) side periphery of the substrate W. A negative pressure is supplied to the suction pads of each suction member 513 as necessary, whereby the four corners of the substrate W are sucked and held by the chuck mechanism 51 from below.

  The substrate W is transported by the chuck mechanism 51 moving in the X direction while holding the substrate W. Thus, the linear motors 88L and 88R, a mechanism (not shown) for supplying negative pressure to each suction member 513, the control unit 9 for controlling these, and the like are integrated into the suction / travel control mechanism 52 of FIG. Is functioning as

  As shown in FIGS. 1 and 4, the chuck mechanism 51 holds the lower surface Wb of the substrate W above the upper surfaces of the stages of the floating stage unit 3, that is, the inlet floating stage 31, the coating stage 32, and the outlet floating stage 33. In this state, the substrate W is transferred. Since the chuck mechanism 51 only holds a part of the outer peripheral edge in the Y direction with respect to the central portion of the substrate W facing the stages 31, 32, 33, the central portion of the substrate W is at the peripheral portion. On the other hand, it will bend downward. The levitation stage unit 3 has a function of controlling the vertical position of the substrate W to maintain a horizontal posture by applying buoyancy to the central portion of the substrate W.

  Among the stages of the levitation stage unit 3, the exit levitation stage 33 has a lower position where the upper surface position is lower than the upper surface position of the chuck mechanism 51, and an upper position where the upper surface position is higher than the upper surface position of the chuck mechanism 51. Can be moved up and down. For this purpose, the outlet levitation stage 33 is supported by a lift drive mechanism 36.

  Next, the configuration of the levitation control mechanism 35 will be described with reference to FIG. FIG. 5 is a diagram showing the configuration of the levitation stage unit and the levitation control mechanism. In FIG. 5, for the levitation stage unit 3, all of the coating stage 32 and a part of the inlet levitation stage 31 and the outlet levitation stage 33 are schematically shown. Show.

  The levitation control mechanism 35 includes a compression unit 351 such as a compressor and a temperature adjustment unit 352, and adjusts the air compressed by the compression unit 351 to a predetermined temperature by the temperature adjustment unit 352 to generate compressed air for levitation. The piping 353 for circulating the compressed air is branched into four and connected to the inlet levitation stage 31, the coating stage 32, the outlet levitation stage 33, and the gas supply pipe 6 via the pressure control unit 354, respectively. All of the four pressure controllers 354 have the same configuration, and perform pressure control of compressed air and supply / stop of compressed air according to a command from the control unit 9.

  Each pressure control unit 354 includes a filter 354a, a needle valve 354b, a flow meter 354c, a pressure meter 354d, and an air operation valve 354e. For example, in the pressure control unit 354 provided corresponding to the outlet levitation stage 33, when the air operation valve 354e is opened in accordance with a command from the control unit 9, the compressed air cleaned through the filter 354a is supplied to the needle valve. After the pressure is adjusted by 354b, it passes through the flow meter 354c, the pressure gauge 354d, and the air operation valve 354e, and is sent by pressure to the ejection hole 331 provided in the outlet levitation stage 33. As a result, the temperature-controlled compressed air is ejected from the ejection holes 331, and the substrate W is floated by the gas pressure. At this time, the temperature of the outlet atmosphere (reference numeral AM2 in FIG. 6 described later) formed between the lower surface Wb of the substrate W and the outlet floating stage 33 is substantially the temperature of the compressed air. This also applies to the pressure control unit 354 provided corresponding to the inlet levitation stage 31.

  Similarly to the above, the pressure controller 354 provided corresponding to the coating stage 32 also sends compressed air toward the coating stage 32 in response to the opening of the air operation valve 354e. In this coating stage 32, a plurality of holes are distributed in a matrix at a pitch narrower than that of the ejection holes 312, 331, and half of them are supplied with the compressed air as the ejection holes 321, and the substrate W It ejects toward the lower surface Wb. At this time, the substrate W is lifted by the gas pressure, and the temperature of the coating atmosphere (the symbol AM1 in FIG. 6 described later) formed between the lower surface Wb of the substrate W and the coating stage 32 is substantially compressed. It becomes air temperature.

  Further, in order to stabilize the pressure in the coating atmosphere, the other half is connected as a suction hole 322 to a suction part 356 through a suction pipe 355. This suction part 356 includes a blower 356a as a suction means, a pressure gauge 356b, and a relief valve 356c, and the pressure in the suction hole 322 connected via the suction pipe 355 rather than the suction pressure obtained by the blower 356a. When the pressure is high, fine adjustment for keeping the pressure in the coating atmosphere constant can be performed by releasing air from the relief valve 356c through the suction hole 322 and the suction pipe 355 to the outside.

  Further, the remaining pressure control unit 354 is connected to the gas supply pipe 6. In the pressure control unit 354, when the air operation valve 354e is opened in accordance with a command from the control unit 9, the compressed compressed air is pumped to the gas supply pipe 6 as in the other pressure control units 354. . At the top of the gas supply pipe 6, there are a plurality of jet outlets (see reference numeral 61 in FIG. 6 described later) along the longitudinal direction of the gas supply pipe 6 (direction Y perpendicular to the drawing sheet). It is provided in a row, and is discharged toward the gap region CL from each jet port, and the temperature of the boundary atmosphere (reference numeral AM3 in FIG. 6 described later) is the temperature of the coating atmosphere and the outlet atmosphere adjacent to the boundary atmosphere. Move closer to. As described above, in the present embodiment, the floating control mechanism 35 functions as a part of the “temperature control mechanism” of the present invention in addition to the function of floating the substrate W. Of course, in order to pressure-feed the temperature-controlled compressed air to the gas supply pipe 6, a compression unit 351, a temperature control unit 352, a pipe 353 and a pressure control unit 354 are provided exclusively, and these and the gas supply pipe 6 are used to You may comprise the "temperature control mechanism" of invention.

  Next, a coating process performed by the coating apparatus 1 configured as described above will be described with reference to FIG. In the present embodiment, the calculation means controls each part of the apparatus as follows according to a control program stored in advance in the storage means, thereby applying to the substrate W while suppressing the temperature difference between the boundary atmosphere, the application atmosphere, and the outlet atmosphere. Execute the process.

  In the present embodiment, the preliminary ejection process is executed by moving the nozzle 71 used for the coating process to the preliminary ejection position. In addition, the injection of compressed air in the levitation stage unit 3 is started to float the substrate W carried in, and the discharge of compressed air from the gas supply pipe 6 is started to reduce the above temperature difference. To be prepared. The nozzle 71 discharges a predetermined amount of the coating liquid toward the preliminary discharge roller 752 at the preliminary discharge position, so that the discharge amount of the coating liquid from the nozzle 71 can be stabilized. In addition, the cleaning process of the nozzle 71 may be performed prior to the preliminary discharge process.

  Next, loading of the substrate W into the coating apparatus 1 is started. A substrate W to be processed is placed on the input conveyor 100 by another upstream processing unit, a transport robot, and the like, and the roller conveyor 101 rotates to transport the substrate W in the (+ X) direction. At this time, the nozzle 71 performs the preliminary discharge process at the preliminary discharge position. Further, the chuck mechanism 51 is retracted and positioned downstream of the inlet levitation stage 31.

  When the input conveyor 100 and the input transfer unit 2 in which the upper surface of the roller conveyor 21 is positioned at the same height as the roller conveyor 101 of the input conveyor 100 cooperate with each other, the substrate W is ejected by compressed air. It is transported to the upper part of the entrance levitation stage 31 that gives buoyancy to the surface. At this time, the upper surface of the entrance levitation stage 31 is lower than the upper surface of the roller conveyor 21, and the substrate W is in a state where the upstream end (the rear end in the moving direction) rides on the roller conveyor 21. Therefore, the substrate W does not slide on the entrance levitation stage 31.

  When the substrate W is thus carried into the entrance levitation stage 31, the lift pins provided on the entrance levitation stage 31 are positioned by the lift pin drive mechanism 34 at an upper position where the upper end protrudes above the upper surface of the entrance levitation stage 31. . As a result, both ends in the Y direction of the substrate W, more specifically, the substrate W with which the lift pins abut are lifted.

  Then, the chuck mechanism 51 moves in the (−X) direction and moves to the transfer start position directly below the substrate W. Since both ends in the Y direction of the substrate W are lifted by the lift pins 311, it is possible to avoid the chuck mechanism 51 entering the lower side of the substrate W from coming into contact with the substrate W. From this state, the upper surface of the roller conveyor 21 and the lift pins descends below the upper surface of the chuck mechanism 51, so that the substrate W is transferred to the chuck mechanism 51. The chuck mechanism 51 holds the peripheral edge of the substrate W by suction.

  Thereafter, the substrate W is transported in a state where the peripheral portion is held by the chuck mechanism 51 and the central portion is maintained in a horizontal posture by the floating stage portion 3. Subsequently, the chuck mechanism 51 moves in the (+ X) direction, so that the substrate W is transported to the application start position. In parallel with this, the nozzle 71 is moved and positioned from the preliminary discharge position to the application position. The application start position is the position of the substrate W such that the downstream end (the leading side in the movement direction) of the substrate W comes to a position immediately below the nozzle 71 positioned at the application position. In many cases, the coating liquid is not applied to the end portion of the substrate W as a blank region. In such a case, the downstream end portion of the substrate W is advanced from the position directly below the nozzle 71 by the length of the blank region. Becomes the application start position.

  When the nozzle 71 is positioned at the application position, the application process is executed as follows. That is, the coating liquid discharged from the discharge port of the nozzle 71 is deposited on the upper surface Wf of the substrate W. Further, when the chuck mechanism 51 transports the substrate W at a constant speed, a coating operation is performed in which the nozzle 71 applies a coating solution to the upper surface Wf of the substrate W. As shown in FIG. A coating film CF having a certain thickness is formed by the liquid.

The coating operation is continued until the substrate W is transported to the end position where the coating should be terminated. When the substrate W reaches the end position, the transport of the substrate W is temporarily stopped as shown in FIG. Is removed from the application position and returned to the preliminary discharge position. Thereafter, the preliminary ejection process is executed again, and the transport of the substrate W is resumed. By such a substrate transport operation, the substrate W carrying the coating film CF passes from above the coating stage 32 above the gap region CL and is transported above the exit floating stage 33. At this time, the substrate W has the following three atmospheres:
A coating atmosphere AM1 formed between the lower surface Wb of the substrate W and the coating stage 32;
A boundary atmosphere AM3 sandwiched between the lower surface Wb of the substrate W and the gap region CL;
An exit atmosphere AM2 formed between the lower surface Wb of the substrate W and the exit levitation stage 33;
On the other hand, it is conveyed while contacting in this order. Therefore, if there are temperature differences among the coating atmosphere AM1, the boundary atmosphere AM3, and the outlet atmosphere AM2, coating unevenness may occur in the coating film CF. In particular, while the substrate conveyance is temporarily stopped, the coating unevenness may become remarkable due to the influence of the temperature difference.

  However, in this embodiment, an air flow is generated in the boundary atmosphere AM3 by the compressed air A3 ejected from the gas supply pipe 6, and mixed with the compressed air A1 and A2 supplied to the coating atmosphere AM1 and the outlet atmosphere AM2, respectively. The temperature of the atmosphere AM3 is brought close to the temperatures of the coating atmosphere AM1 and the outlet atmosphere AM2, and the temperature difference is reduced. Moreover, in the present embodiment, the compressed air A1, A3, A2 that is pumped through the pipe 353 branched from the temperature control unit 352 is ejected for any of the coating atmosphere AM1, the boundary atmosphere AM3, and the outlet atmosphere AM2. Therefore, the temperatures of the coating atmosphere AM1, the boundary atmosphere AM3, and the outlet atmosphere AM2 are almost the same value. Such temperature adjustment is performed while the substrate conveyance is continued and during the temporary stop, so that the occurrence of the coating unevenness can be effectively suppressed.

  Next, when the chuck mechanism 51 reaches the conveyance end position where the downstream end of the substrate W is positioned on the output transfer unit 4, the movement of the chuck mechanism 51 is stopped and the suction holding is released. And the raising of the roller conveyor 41 of the output transfer part 4 and the raising of the exit floating stage 33 are sequentially started.

  Then, the roller conveyor 41 and the outlet floating stage 33 rise above the upper surface of the chuck mechanism 51, so that the substrate W is separated from the chuck mechanism 51. When the roller conveyor 41 rotates in this state, a propulsive force in the (+ X) direction is applied to the substrate W. Accordingly, when the substrate W moves in the (+ X) direction, the substrate W is further carried out in the (+ X) direction by the cooperation of the roller conveyor 41 and the roller conveyor 111 of the output conveyor 110 (step S21), and finally downstream. It is paid out to the side unit. If there is a next substrate to be processed, the same processing as described above is repeated, and if not, the processing ends. At this time, the nozzle 71 is returned to the standby position.

  As described above, in the present embodiment, the gas supply pipe 6 is disposed vertically below the gap region CL, and the compressed air A3 is ejected into the gap region CL in response to the supply of compressed air from the levitation control mechanism 35. . For this reason, it is possible to effectively suppress the occurrence of coating unevenness in the coating film CF formed on the upper surface Wf of the substrate W, and the coating process can be performed satisfactorily.

  As described above, in this embodiment, the chuck mechanism 51 functions as the “conveying unit” of the present invention. Further, the exit levitation stage 33 corresponds to an example of the “exit stage” of the present invention. Further, the compressed air A1 to A3 correspond to the “first gas”, “second gas”, and “third gas” of the present invention, respectively. The boundary atmosphere AM3 corresponds to an example of the “atmosphere” of the present invention. Furthermore, the gas supply pipe 6 corresponds to an example of the “gas supply unit” of the present invention.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the combination of the gas supply pipe 6 and the levitation control mechanism 35 functions as the “temperature control mechanism” of the present invention, but another supply means is employed instead of the gas supply pipe 6. Also good. For example, as shown in FIG. 7, an ejection hole 332 provided with an opening so as to face the boundary atmosphere AM <b> 3 with respect to the (−X) direction end adjacent to the gap region CL in the outlet levitation stage 33. You may provide as a 1st ejection hole. And you may comprise so that a part of compressed air A2 pressure-fed from the temperature control part 352 to the exit levitation | floating stage 33 may be directly supplied to boundary atmosphere AM3 via the ejection hole 332. In this case, the combination of the ejection hole 332 and the levitation control mechanism 35 functions as the “temperature control mechanism” of the present invention.

  Moreover, the form of the ejection hole that functions as a part of the temperature control mechanism is not limited to the ejection hole 332, and for example, as shown in FIG. 8, the ejection hole provided with an opening so as to face the gap region CL. 333 may be used as the “second ejection hole” of the present invention. In this case, similarly to the embodiment shown in FIG. 6, the compressed air A2 is supplied to the boundary atmosphere AM3 through the gap region CL, and the temperature difference can be reduced. Further, the first ejection hole 332 and the second ejection hole 333 may be provided in parallel to the outlet levitation stage 33. Of course, you may provide in the application | coating stage 32 about the ejection hole which functions as a part of temperature control mechanism.

  Further, in the above embodiment, the compressed air A3 is positively supplied to the boundary atmosphere AM3 to bring the temperature of the boundary atmosphere AM3 close to the temperature of the coating atmosphere AM1 and the outlet atmosphere AM2. However, as shown in FIG. The sealing member 37 may be provided in the CL, and the gap region CL may be closed to mix the compressed air A1 and A2 in the boundary atmosphere AM3 so that the temperature can be made uniform. In the present embodiment, since the outlet levitation stage 33 can be moved up and down, it is preferable that the seal member 37 is made of a material having elasticity or flexibility, or adopts a stretchable structure. It is. Further, the seal member 37 may be applied to the embodiment shown in FIG.

  INDUSTRIAL APPLICABILITY The present invention can be applied to all coating apparatuses and coating methods that apply a coating liquid on the upper surface of a substrate while being transported in a horizontal direction in a state where the substrate is floated from a stage.

DESCRIPTION OF SYMBOLS 1 ... Coating apparatus 6 ... Gas supply pipe (gas supply part)
32 ... coating stage 33 ... exit levitation stage (exit stage)
332... (First) ejection hole 333... (Second) ejection hole 51... Chuck mechanism (conveyance unit)
71 ... Nozzle A1 ... Compressed air (first gas)
A2: Compressed air (second gas)
A3: Compressed air (third gas)
AM3 ... Boundary atmosphere W ... Substrate Wf ... Upper surface (of substrate) Wb ... Lower surface of (substrate) X ... Transfer direction

Claims (8)

A transport unit for holding and transporting the substrate;
A nozzle for discharging and applying a coating liquid onto the upper surface of the substrate to be conveyed;
An application stage which is arranged at a position below the nozzle and floats the substrate in a horizontal posture by ejecting a first gas toward the lower surface of the substrate to be conveyed;
The substrate is disposed by being separated from the coating stage on the downstream side of the coating stage in the transport direction in which the substrate is transported, and ejecting a second gas toward the lower surface of the substrate transported from the coating stage. An exit stage that floats in a horizontal position,
The temperature of the atmosphere sandwiched between the gap region sandwiched between the coating stage and the outlet stage and the lower surface of the substrate that is transported over the gap region is the temperature of the first gas and the second gas. And a temperature control mechanism that controls the coating device so as to approach the coating device. The coating apparatus according to claim 1,
The said temperature control mechanism is a coating device which has a gas supply part which supplies 3rd gas to the said atmosphere through the said clearance gap area | region. The coating apparatus according to claim 2,
The coating apparatus in which the first gas, the second gas, and the third gas are all at the same temperature. The coating apparatus according to claim 1,
The temperature control mechanism has a first ejection hole provided in the outlet stage to eject the second gas toward the atmosphere, and the second gas ejected from the first ejection hole is brought into the atmosphere. Application device to supply. The coating apparatus according to claim 1 or 4,
The temperature control mechanism has a second ejection hole that is provided in the outlet stage and ejects the second gas toward the gap region, and the second gas ejected from the second ejection hole is removed from the gap. A coating apparatus that supplies the atmosphere through the region. The coating apparatus according to claim 1 or 4,
The temperature control mechanism is a coating apparatus having a seal member that is provided in the gap region and prevents the first gas and the second gas from flowing out from the atmosphere into the gap region. The coating apparatus according to any one of claims 4 to 6,
A coating apparatus in which the first gas and the second gas are both at the same temperature. A coating stage that floats the substrate in a horizontal posture by ejecting a first gas toward the lower surface of the substrate, and a second gas that is ejected toward the lower surface of the substrate at a position separated from the coating stage. A coating method in which a coating liquid is ejected from the top of the coating stage toward the upper surface of the substrate while being transported in the order of an exit stage that floats the substrate in a horizontal posture,
When the substrate on which the coating liquid has been applied is positioned above a gap region sandwiched between the coating stage and the exit stage, the lower surface of the substrate and the gap that are transported over the gap region A coating method, wherein the temperature of the atmosphere sandwiched between the regions is controlled to be close to the temperatures of the first gas and the second gas.

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