JP6737649B2 - Coating device and coating method - Google Patents

Description

The present invention relates to a coating technique for coating a coating liquid on the other main surface of a substrate while transporting the substrate in a transporting direction while blowing gas onto one main surface of the substrate to float the substrate. The above-mentioned substrates include semiconductor substrates, photomask substrates, liquid crystal display substrates, organic EL display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disc substrates, magnetic disc substrates, and optical substrates. A magnetic disk substrate and the like are included.

In the manufacturing process of electronic components such as semiconductor devices and liquid crystal display devices, a coating device that coats a processing liquid on the surface of a substrate is used. As such a coating apparatus, a coating liquid is applied from a slit nozzle to the other main surface (front surface) of the substrate while the substrate is being transported while the gas is blown onto the one main surface (back surface) of the substrate. There is known a device that discharges the liquid and applies the coating liquid to almost the entire substrate (see Patent Document 1).

JP, 2010-227850, A

The coating apparatus is supposed to coat the entire other main surface of the substrate with the coating liquid, but of course, the so-called divided coating is performed by the apparatus to form a plurality of coating blocks on the other main surface of the substrate. Is also possible. For example, when forming two coating blocks, it is necessary to perform the following steps (A) to (D).

(A) The substrate is transported in a predetermined transport direction to a position (first coating start position) where the other main surface of the substrate faces the discharge port of the slit nozzle, and the substrate is temporarily transported at the first coating start position. The first transfer step of restarting the transfer of the substrate in the transfer direction after the first stop,
(B) In the first transfer step, the discharge of the coating liquid from the discharge port is started while the transfer of the substrate is temporarily stopped, and the transfer is performed during the transfer of the substrate in the transfer direction. A first block forming step of continuously discharging the coating liquid from a discharge port to form a first coating block on the other main surface of the substrate;
(C) The substrate is transported in the transport direction to a position (second coating start position) where a region different from the first coating block on the other main surface of the substrate faces the ejection port of the slit nozzle, and the second coating is started. A second transfer step of restarting the transfer of the substrate in the transfer direction after temporarily stopping the transfer of the substrate at the position;
(D) In the second transfer step, the discharge of the coating liquid from the discharge port is started while the transfer of the substrate is temporarily stopped, and the transfer is performed during the transfer of the substrate in the transfer direction. A second block forming step of continuing the discharge of the coating liquid from the discharge port to form a second coating block on the other main surface of the substrate.

Here, the problem is the step (C). That is, in the step (C), it is necessary to stop the transfer of the substrate while holding the undried first coating block, and the transfer mechanism becomes uneven in the first coating block while the transfer is stopped. This "conveyance mechanism unevenness" is caused by the floating conveyance. That is, since the gas is blown onto the one main surface of the substrate so as to float, the substrate temperature is different between the region where the gas is strongly blown and the other region. This non-uniformity of the substrate temperature is reflected in the first coating block, and the progress of drying in the first coating block is partially different while the substrate is temporarily stopped.

This invention has been made in view of the above problems, and is discharged from the discharge port of the nozzle while intermittently transporting the substrate in the transport direction in a state where the gas is blown to one main surface of the substrate to float the substrate. In a coating technique for forming a plurality of coating blocks by dividing the coating liquid on the other main surface of the substrate to form a plurality of coating blocks, an object is to form each coating block satisfactorily without being affected by floating transportation. ..

One aspect of the present invention is a coating apparatus, which is a levitation mechanism that blows gas onto one main surface of a substrate to levitate the substrate, and a transport mechanism that intermittently transports the substrate levitated by the levitation mechanism in a transport direction. And a plurality of nozzles having a discharge port for discharging the coating liquid to the other main surface of the substrate floated by the levitation mechanism, and the transfer mechanism is configured such that the other main surface of the substrate faces the plurality of discharge ports. After transferring the substrate to the start position and temporarily stopping the transfer of the substrate at the coating start position, restarting the transfer of the substrate in the transfer direction, the plurality of nozzles are arranged in the transfer direction to transfer the substrate. While the liquid is temporarily stopped, the discharge of the coating liquid from the discharge port is started, and the discharge of the coating liquid from the discharge port is continued while the substrate is being transported in the transport direction, so that a plurality of coating liquids are formed on the other main surface of the substrate. The feature is that a coating block is formed.

Further, according to another aspect of the present invention, the coating liquid ejected from the ejection port of the nozzle is intermittently transported in the transport direction in a state where the gas is blown to one main surface of the substrate to float the substrate. A coating method for coating on the other main surface of the substrate, arranging a plurality of nozzles in the transport direction, and transporting the substrate to a coating start position where the other main surface of the substrate faces discharge ports of the plurality of nozzles. The step of temporarily stopping the transfer of the substrate at the coating start position, and the discharge of the coating liquid from the discharge ports after starting the discharge of the coating liquid from the plurality of discharge ports while the transfer of the substrate is stopped. A step of restarting the transfer of the substrate in the transfer direction while continuing to form a plurality of coating blocks on the other main surface of the substrate.

In the invention thus configured, the plurality of nozzles are arranged in the substrate transport direction. Then, the ejection of the coating liquid from each nozzle is started while the transportation of the substrate is temporarily stopped, and the ejection is continued during the subsequent transportation of the substrate to form a plurality of coating blocks. Since the formation of a plurality of coating blocks is performed in parallel in this way, the occurrence of the above-described unevenness of the transport mechanism is effectively suppressed, as compared with the conventional technique of sequentially forming a plurality of coating blocks.

As described above, according to the present invention, the ejection of the coating liquid from the plurality of nozzles is started while the transfer of the substrate is temporarily stopped, and subsequently, the application is performed during the transfer of the substrate in the transfer direction. Since the plurality of coating blocks are formed on the other main surface of the substrate by continuing the discharge of the liquid, it is possible to suppress the unevenness of the transport mechanism and form each coating block satisfactorily.

It is drawing which shows one Embodiment of the coating device concerning this invention. It is the top view which removed the coating mechanism from FIG. 1A. It is a block diagram which shows the control mechanism which controls the coating device shown in FIG. 1A. It is a top view of a levitation mechanism. It is a side view which shows typically the relationship between a floating mechanism and a coating mechanism. It is a side view of the coating device shown in FIG. 1A. It is a figure which shows operation|movement of the coating device shown to FIG. 1A. It is a figure which shows operation|movement at the timing T2 in FIG. 5 typically. It is a figure which shows typically operation|movement at the timing T3 in FIG. It is a figure which shows operation|movement at the timing T4 in FIG. 5 typically. FIG. 6 is a diagram schematically showing an operation at timing T5 in FIG.

FIG. 1A is a drawing showing an embodiment of a coating apparatus according to the present invention, and is a plan view seen from vertically above, and FIG. 1B is a plan view with the coating mechanism removed from FIG. 1A. FIG. 2 is a block diagram showing a control mechanism for controlling the coating device shown in FIG. 1A. Note that in FIGS. 1A and 1B and in each of the drawings to be described later, in order to clarify the positional relationship of each part of the apparatus, the transport direction of the substrate W is set to the “X direction”, and the left-hand side to the right-hand side in FIGS. 1A and 1B. The horizontal direction toward the side is referred to as "+X direction", and the opposite direction is referred to as "-X direction". Further, in the horizontal direction Y orthogonal to the X direction, the front side of the device is referred to as "-Y direction" and the back side of the device 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.

The coating apparatus 1 is a slit coater that receives a horizontally oriented rectangular substrate W conveyed from a roller conveyor 100 and coats a coating liquid on a surface Wf of the substrate W to form two coating blocks. In this coating apparatus 1, a transfer mechanism 2 is provided adjacent to the roller conveyor 100. The transfer mechanism 2 receives the substrate W from the roller conveyor 100 and transfers it onto the levitation mechanism 3.

The levitation mechanism 3 has three levitation units 3A to 3C. These floating units 3A to 3C are arranged in the transport direction X of the substrate W, as shown in FIG. 1B. More specifically, the upstream levitation unit 3A is arranged adjacent to the transfer mechanism 2 on the most upstream side, that is, the (−X) direction side, and the downstream levitation unit 3C is arranged on the most downstream side, that is, the (+X) direction side. ing. Further, the central floating unit 3B is arranged between the upstream floating unit 3A and the downstream floating unit 3C.

FIG. 3A is a plan view of the levitation mechanism, and FIG. 3B is a side view schematically showing the relationship between the levitation mechanism and the coating mechanism. In addition, in these drawings, all of the central levitation unit 3B and a part of the upstream levitation unit 3A and the downstream levitation unit 3C are schematically shown.

Both the upstream levitation unit 3A and the downstream levitation unit 3C are formed with a large number of air ejection holes 31 dispersed in a matrix over the entire surface of a single plate-shaped stage surface 32. Then, the compressed air is applied to each of the ejection holes 31, so that the substrate W is levitated by the gas pressure generated by the ejection of the compressed air from each of the ejection holes 31. As a result, in the upstream levitation unit 3A and the downstream levitation unit 3C, the substrate W floats above the stage surface 32 by a predetermined levitation height, for example, 10 to 500 micrometers. In addition, in order to supply the compressed air to each ejection hole 31, for example, the configuration described in Patent Document 1 can be used.

Although not shown in FIGS. 3A and 3B, the downstream levitation unit 3C has a plurality of lift pins and lift pin lifting mechanisms other than the ejection holes 31. The plurality of lift pins are provided so as to face the entire back surface Wb of the substrate W at predetermined intervals by sewing the gaps between the ejection holes 31. Then, the lift pins are vertically moved (Z axis direction) by a lift pin lifting mechanism installed below the stage surface 32. That is, the tip of the lift pin descends to the (-Z) direction side of the stage surface 32 of the downstream levitation unit 3C when descending, and the tip of the lift pin transfers the substrate W to the transfer robot (not shown) when ascending. Rise to. Since the lower surface of the substrate W is supported and lifted by the lift pins thus lifted, the substrate W moves up from the stage surface 32 of the downstream floating unit 3C. As a result, the transfer robot can unload the substrate W from the coating apparatus 1.

On the other hand, the central levitation unit 3B is composed of three levitation units 3B1 to 3B3. These floating portions 3B1 to 3B3 are arranged in the transport direction X of the substrate W, as shown in FIGS. 3A and 3B. More specifically, the levitation unit 3B1 is arranged adjacent to the upstream levitation unit 3A on the most upstream side, that is, the (−X) direction side, and the levitation unit 3B3 is located on the most downstream side, that is, the (+X) direction side, the downstream levitation unit 3C. Is located adjacent to. Further, the floating portion 3B2 is arranged between the floating portions 3B1 and 3B3. Of the three levitation units, in the levitation unit 3B2, like the upstream levitation unit 3A and the downstream levitation unit 3C, a large number of air ejection holes 31 are dispersed in a matrix over the entire surface of one plate-shaped stage surface 32. Has been formed. Then, compressed air is applied to each of the ejection holes 31. On the other hand, as shown in FIG. 3B, the floating portions 3B1 and 3B3 are arranged to face the nozzle units 51 of the coating mechanisms 5A and 5B, respectively, and the height position of the substrate W in the vertical direction Z is set to be higher than that of the floating portions 3B2. It can be controlled with high precision. Since the flying heights 3B1 and 3B3 and the flying height 3B2 are different in this way, the flying heights 3B1 and 3B3 will be referred to as “precision flying heights” and the flying height 3B2 will be referred to as “normal flying heights” hereinafter. ..

The precision floating parts 3B1 and 3B3 have the same structure. Therefore, the configuration of the precision levitation unit 3B1 will be described, and with respect to the precision levitation unit 3B3, the same components will be denoted by the same reference numerals and description thereof will be omitted. The precision floating portion 3B1 has a rectangular plate-shaped stage surface 33. The stage surface 33 is provided with a plurality of holes dispersed in a matrix at a pitch narrower than that of the ejection holes 31 provided in the upstream levitation unit 3A, the downstream levitation unit 3C, and the normal levitation unit 3B2. Further, unlike the upstream levitation unit 3A, the downstream levitation unit 3C, and the normal levitation unit 3B2, in the precision levitation unit 3B1, half of the holes function as compressed air ejection holes 34a, and the other half function as suction holes 34b. .. That is, the compressed air is ejected from the ejection holes 34a toward the back surface Wb of the substrate W to send the compressed air into the space SP (FIG. 3B) between the stage surface 33 and the back surface Wb of the substrate W. On the other hand, the air is sucked from the space SP via the suction holes 34b. As the air is jetted and sucked into the space SP in this way, the air flow of the compressed air jetted from the jet holes 34a in the space SP spreads in the horizontal direction and then the jet hole 34a. Will be sucked from the suction hole 34b adjacent to the space SP, and the pressure balance in the air layer (pressure gas layer) spreading in the space SP will be more stable, and the flying height of the substrate W will be highly accurate and stable. Can be controlled. In addition, in order to supply the compressed air to the ejection holes 34a and suck the air from the suction holes 34b, for example, the configuration described in Patent Document 1 can be used.

The coating apparatus 1 is provided with a transport mechanism 4 for intermittently transporting the substrate W floated by the upstream levitation unit 3A in the transport direction X. Hereinafter, the configuration of the transport mechanism 4 will be described with reference to FIGS. 1A, 1B and 4.

FIG. 4 is a side view of the coating device shown in FIG. 1A. The transport mechanism 4 has a function of transporting the substrate W in the transport direction X while floating the substrate W by the levitation mechanism 3 while sucking and holding both end portions in the Y direction of the substrate W supported by the levitation mechanism 3 in a floating state. have. As shown in FIG. 4, the transport mechanism 4 includes a plurality of chuck portions 41 that suck and hold the substrate W. Here, two chuck members 41a are arranged in the X direction, and two chuck members 41 that are integrally movable in the X direction are provided, one each on the left and right, for a total of two chuck members 41a. It may be provided as 41. In the present embodiment, the above-described two chuck portions 41 have a bilaterally symmetrical structure (symmetrical on the +Y side and the −Y side), and hold the substrate W by suction on each of the left and right sides. Further, the transport mechanism 4 includes a transport chuck travel guide 42, a transport chuck linear motor 43, a transport chuck linear scale 44, and a chuck lifting cylinder 45. The chuck unit 41 can be moved up and down by the operation of the chuck lift cylinder 45. Therefore, the chuck elevating cylinder 45 operates in response to the holding command from the control unit 9 that controls the entire apparatus, and the chuck unit 41 moves up to both ends of the (+Y) side and (−Y) side substrates W. The lower surface of the part is supported and adsorbed and held. Further, the transport chuck travel guide 42 is extended in the X direction on the base 10 of the coating apparatus 1, and the transport chuck linear motor 43 is operated in response to a transport command from the control unit 9 to cause the chuck unit 41 to move. Is reciprocated in the transport direction X along the transport chuck travel guide 42. As a result, the substrate W held by the chuck portion 41 is transported in the transport direction X. In this embodiment, the position of the substrate W in the transfer direction X can be detected by the transfer chuck linear scale 44, and the control unit 9 controls the transfer chuck linear motor 43 based on the detection result of the transfer chuck linear scale 44. Drive control.

The substrate W is transported in the transport direction X in the so-called face-up state with the front surface Wf facing vertically upward by the transport mechanism 4 described above. In order to apply the coating liquid to the front surface Wf of the substrate W during the transport, The two coating mechanisms 5A and 5B are arranged along the transport direction X. Of these, the upstream coating mechanism 5A located on the upstream side has a nozzle unit 51 fixedly arranged with respect to the base 10 in the transport direction X, as shown in FIG. 1A. Further, a nozzle cleaning standby unit 52 is provided so as to be capable of reciprocating on the upstream side (the left-hand side in the figure) of the nozzle unit 51 in the transport direction X.

As shown in FIG. 4, the nozzle unit 51 includes a slit nozzle 511 extending in the Y direction so as to face the front surface Wf of the substrate W, a nozzle support member 512 that supports the slit nozzle 511, and a transport mechanism in the Y direction. The lifting unit 513 is provided on the outer side of 4 and has a bilaterally symmetrical structure (symmetrical on the +Y side and the −Y side). In this embodiment, the slit nozzle 511 is configured to move up and down in the vertical direction Z via the nozzle support member 512 by the pair of lifts 513. More specifically, each elevating part 513 has a columnar member 514 standing upright vertically (+Z) from the base 10, a ball screw 515 attached to the columnar member 514 in a state of extending in parallel to the vertical direction Z, A rotation motor 516 connected to the upper end of the ball screw 515 and a bracket 517 screwed to the ball screw 515 are provided. When the rotation motor 516 operates in response to the rotation command from the control unit 9, the ball screw 515 rotates, and the bracket 517 moves up and down in the vertical direction Z according to the rotation amount. Both ends of the nozzle support member 512 are attached to the brackets 517 on the (+Y) direction side and the (−Y) direction side configured in this way, respectively, and are supported so as to be able to move up and down through the nozzle support member 512. .. A slit nozzle 511 is attached to the lower end of the nozzle support member 512 with the discharge port 511a facing downward. Therefore, by controlling the rotary motor 516 by the control unit 9, it is possible to move the slit nozzle 511 up and down to bring the ejection port 511a closer to the front surface Wf of the substrate W transported by the transport mechanism 4, or conversely to separate it upward. Has become. Further, the control unit 9 controls the rotation motor 516 based on the output of a flying height detection sensor (reference numeral 53 in FIG. 3B), which will be described later, whereby the distance between the surface Wf of the substrate W and the ejection port 511a is controlled. It can be adjusted with high precision. Then, when the coating liquid is pressure-fed to the slit nozzle 511 from the coating liquid supply mechanism (not shown) with the ejection port 511a being close to the front surface Wf of the substrate W, the ejection liquid is ejected from the ejection port 511a toward the front surface Wf of the substrate W. To be done. On the other hand, when the application of the coating liquid is completed, as shown in FIG. 4, the slit nozzle 511 rises to a position (cleaning standby position) sufficiently distant from the substrate W upward (+Z), and the nozzle cleaning standby unit 52 causes the slit nozzle 511 to move. The discharge port 511a of 511 can be cleaned. The slit nozzle 511 has a protective member (reference numeral 6B1 in FIG. 3B) for protecting the tip of the nozzle, a flying height detection sensor (reference numeral 53 in FIG. 3B), and a vibration sensor (reference numeral 6B2 in FIG. 3B). Are attached, which will be described later.

The nozzle cleaning standby unit 52 is a device that cleans and removes the resist liquid from the tip of the slit nozzle 511 that has supplied the coating liquid to the front surface Wf of the substrate W, and the discharge port 511a of the slit nozzle 511 is Is prepared in a state suitable for the coating process. As shown in FIGS. 3B and 4, the nozzle cleaning standby unit 52 includes a cleaning standby unit 524 which mainly includes a roller 521, a cleaning unit 522, a roller butt 523, and the like, which performs nozzle cleaning and liquid pool formation. There is. In the cleaning standby unit 524, the ejection port 511a of the slit nozzle 511 after the coating process is performed is cleaned. Further, when a constant amount of resist liquid is discharged from the discharge port 511a in a state where the slit nozzle 511 is brought close to the outer peripheral surface of the roller 521, a pool of resist liquid is formed at the discharge port 511a. When the liquid pool is uniformly formed in the ejection port 511a in this way, the subsequent coating process can be performed with high accuracy. In this way, the discharge port 511a of the slit nozzle 511 is initialized and prepared for the next coating process. The roller 521 is rotated by driving a roller rotation motor (not shown) according to a rotation command from the control unit 9. Further, the resist liquid attached to the roller 521 is removed by immersing the lower end in the cleaning liquid stored in the roller butt 523 when the roller 521 rotates.

The cleaning standby unit 524 thus configured is reciprocally moved in the transport direction X by the moving mechanism 525 of the nozzle cleaning standby unit 52. As shown in FIG. 4, the moving mechanism 525 includes two holding portions 526. The holding portion 526 has a bilaterally symmetrical structure (symmetrical on the +Y side and the −Y side), and holds the Y-direction end portion of the cleaning standby portion 524 on each of the left and right sides. Further, the moving mechanism 525 includes a traveling guide 527 used also as the moving mechanism 525 of the other coating mechanism 5B, and a linear motor 528.

As shown in FIG. 1A and FIG. 1B, the traveling guide 527 is extended in the X direction on the base 10 of the coating apparatus 1, and the linear motor 528 is operated in response to a movement command from the control unit 9. The cleaning standby part 524 is reciprocally moved in the transport direction X along the traveling guide 527 to perform nozzle cleaning (a position sandwiched between the slit nozzle 511 positioned at the cleaning standby position and the precision floating portion 3B1). It can be positioned at a retreat position that is away from the cleaning position in the (-X) direction.

The other coating mechanism 5B is arranged downstream of the upstream coating mechanism 5A. The downstream coating mechanism 5B includes a nozzle unit 51 and a nozzle cleaning standby unit 52, like the upstream coating mechanism 5A. The downstream coating mechanism 5B is different from the upstream coating mechanism 5A in that the nozzle cleaning standby unit 52 is arranged on the downstream side of the nozzle unit 51 (on the right-hand side in the figure), and other configurations are basically the same. Since they are the same, the same reference numerals are given to the same components, and the configuration description of the downstream coating mechanism 5B is omitted.

The slit nozzle 511 of the upstream coating mechanism 5A and the slit nozzle 511 provided in the downstream coating mechanism 5B have two coating blocks (reference numeral CBa in FIG. 6D for the front surface Wf of the substrate W, as will be described later in detail. , CBb) are formed in parallel with each other in the transport direction X by a predetermined distance L. Specifically, the distance L is set to a value slightly larger than the size in the X direction of the coating block formed by discharging the coating liquid from each slit nozzle 511 to the front surface Wf of the substrate W, as shown in FIG. 3B. ing.

Further, since the slit nozzle 511 is brought close to the front surface Wf of the substrate W and the coating process is performed, if foreign matter is present on the front surface Wf, the slit nozzle 511 may be damaged by the collision between the foreign matter and the slit nozzle 511. Further, if an error occurs in the position of the slit nozzle 511 due to the collision, it becomes impossible to continue the coating process thereafter. Therefore, in this embodiment, two types of foreign matter detection mechanisms 6A and 6B are provided in order to detect foreign matter existing on the surface Wf of the substrate W.

The foreign matter detection mechanism 6A detects the foreign matter in a non-contact manner on the upstream side of the slit nozzle 511 provided in the upstream coating mechanism 5A in the transport direction X, and has a light projecting unit 6A1 and a light receiving unit 6A2. There is. As shown in FIG. 1B, the light projecting unit 6A1 and the light receiving unit 6A2 are arranged so as to sandwich the precision floating portion 3B1 from the outside in the Y direction. The light projecting section 6A1 and the light receiving section 6A2 are attached to the upper ends of support members (not shown) that are provided upright in the vertical direction Z from the upper surface of the base 10, and the height positions of the light projecting section 6A1 and the light receiving section 6A2 are set. Has been adjusted. More specifically, as shown in FIG. 3B, the light projecting unit 6A1 and the light receiving unit are arranged so that the laser light emitted from the light projecting unit 6A1 passes over the surface Wf of the substrate W and enters the light receiving unit 6A2. 6A2 is provided. Then, the light projecting unit 6A1 irradiates the light receiving unit 6A2 with laser light. On the other hand, the light receiving unit 6A2 receives the laser beam emitted from the light projecting unit 6A1, measures the amount of the received light, and outputs it to the control unit 9. Then, the control unit 9 detects the foreign matter based on the received light amount.

The other foreign matter detection mechanism 6B detects the foreign matter by a contact method, and in the present embodiment, it is attached to both the slit nozzle 511 of the upstream coating mechanism 5A and the slit nozzle 511 of the downstream coating mechanism 5B. The foreign matter detection mechanism 6B includes a protection member 6B1 attached to the slit nozzle 511 on the upstream side of the ejection port 511a in the transport direction X, and a vibration sensor 6B2 that detects vibration of the slit nozzle 511. The protection member 6B1 is a plate member that extends in the horizontal direction Y to protect the nozzle tip of the slit nozzle 511, and is arranged such that the plate surface is orthogonal to the front surface Wf of the substrate W. For this reason, when foreign matter is present on the substrate W when the substrate W is transported to a position directly below the nozzle unit 51, the protective member 6B1 causes the slit nozzle 511 to contact the nozzle tip and the foreign matter on the slit nozzle 511. Prevent damage. When a foreign substance is present, the protective member 6B1 comes into contact with the foreign substance, causing vibration to be generated in the protective member 6B1 and transmitted to the slit nozzle 511. The vibration sensor 6B2 detects this vibration and outputs it to the control unit 9. Then, the control unit 9 detects the foreign matter based on the vibration. In addition to the foreign matter detection mechanism 6B, the slit nozzle 511 has a flying height for detecting the flying height of the substrate W in a non-contact manner at a position where the slit nozzle 511 enters the upper region of the substrate W before the protection member 6B1. The detection sensor 53 is installed. The flying height detection sensor 53 can measure the distance between the levitated substrate W and the upper surface of the stage surface 33 of the precision levitation 3B1, and the control unit 9 is operated according to the detected value. Thus, the position where the slit nozzle 511 descends can be adjusted. As the flying height detection sensor 53, an optical sensor, an ultrasonic sensor, or the like can be used.

As described above, in the present embodiment, by providing the two types of foreign matter detection mechanisms 6A and 6B, the foreign matter can be reliably detected. Moreover, when detecting a foreign substance, the control unit 9 forcibly stops the conveyance of the substrate W to prevent damage to the slit nozzle 511, damage to the substrate W, and the like.

The controller 9 has a function of controlling each part of the coating apparatus 1 as described above. In the control unit 9, a CPU 91 that executes a predetermined processing program to control the operation of each unit, and a memory 92 that stores and stores the processing program executed by the CPU 91 and data generated during the processing. And a display unit 93 for notifying the user of the progress status of processing, detection of foreign matter, and the like as necessary.

Next, an operation of forming two coating blocks on the front surface Wf of the substrate W by the coating device 1 will be described with reference to FIGS. 3B, 5, and 6A to 6D. In the coating apparatus 1, the CPU 91 controls the respective parts of the apparatus according to the processing program as described below to execute the coating processing.

FIG. 5 is a diagram showing the operation of the coating apparatus shown in FIG. 1A. 6A to 6D are diagrams schematically showing the operation at timings T2 to T5 in FIG. 5, respectively. Note that the vertical axis in FIG. 5 is a time axis, and various operations executed for one substrate W are referred to as “substrate transfer/transport operation” and “upstream coating” in order to facilitate understanding of the description. The operation of the mechanism” and the “operation of the downstream coating mechanism” are illustrated separately.

In the coating apparatus 1, prior to receiving the substrate W from the roller conveyor 100, nozzle cleaning and liquid pool formation are performed by the upstream coating mechanism 5A and the downstream coating mechanism 5B at an appropriate timing T1 after the previous coating process is completed. Is performed (steps S21 and S31). That is, in the upstream coating mechanism 5A, as shown in FIG. 3B, the slit nozzle 511 is positioned at the cleaning standby position, and the nozzle cleaning standby unit 52 is located at the position sandwiched between the slit nozzle 511 and the precision floating portion 3B1. Be moved. Then, after the ejection port 511a of the slit nozzle 511 is cleaned by the cleaning unit 522, a certain resist liquid is ejected from the ejection port 511a with the ejection port 511a being close to the outer peripheral surface of the roller 521. A liquid pool is formed (step S21). Further, also in the downstream coating mechanism 5B, nozzle cleaning and liquid pool formation are executed in the same manner as in the upstream coating mechanism 5A (step S31).

When the substrate W is sent from the roller conveyor 100 to the transfer mechanism 2, the transfer mechanism 2 receives the substrate W from the roller conveyor 100 and transfers it to the levitation mechanism 3 (step S11). On the other hand, in the coating mechanisms 5A and 5B, the nozzle cleaning standby unit 52 moves in the (−X) direction and the (+X) direction, respectively, and retracts from the position directly below the slit nozzle 511 (steps S22 and S32). As a result, for example, as shown in FIG. 6A, the slit nozzle 511 can be lowered and the coating liquid can be discharged from the discharge port 511a.

Further, when the preparation for the coating process is completed in this way, the control unit 9 operates the levitation mechanism 3 to eject the compressed air upward. Of course, in the precision levitation units 3B1 and 3B3, air suction is performed in parallel with the jetting of compressed air, so that the substrate can be levitated. As a result, the substrate W transferred to the transfer mechanism 2 floats above the stage surface 32 of the upstream floating unit 3A by a predetermined floating height. Then, the chuck part 41 of the transport mechanism 4 holds the substrate W, and the transport of the substrate W in the transport direction X is started (step S12).

Then, at a timing T2 after a lapse of a certain time from then, as shown in FIG. 6A, the front end portion of the substrate W reaches between the light projecting portion 6A1 and the light receiving portion 6A2. Here, if a foreign matter is present on the front surface Wf of the substrate W, part or all of the light emitted from the light projecting unit 6A1 is blocked by the foreign matter, and the output from the light receiving unit 6A2 changes. The control unit 9 detects whether or not foreign matter is present on the front surface Wf of the substrate W based on the change. In this way, the foreign matter detection is started and continued until the rear end of the substrate W passes through the foreign matter detection mechanism 6A (step S23). As a result, foreign matter is detected in the horizontal direction on the entire surface Wf of the substrate W.

Here, when a foreign substance is detected, the control unit 9 forcibly stops the conveyance of the substrate W and interrupts the coating process. On the other hand, when no foreign matter is detected, the slit nozzle 511 of the upstream coating mechanism 5A starts descending movement before the tip of the substrate W reaches the position directly below the slit nozzle 511 of the upstream coating mechanism 5A, as shown in FIG. 6B, for example. As described above, the slit nozzle 511 is positioned directly above the precision floating portion 3B1 on the upstream side (step S24). Also in the downstream coating mechanism 5B, simultaneously with the upstream coating mechanism 5A or after the upstream coating mechanism 5A, the downward movement of the slit nozzle 511 of the downstream coating mechanism 5B is started, and the slit nozzle 511 is moved to the downstream side precision floating portion 3B3. It is positioned at the position directly above (step S33).

By positioning the slit nozzle 511, the protective member 6B1 is arranged close to the front surface Wf of the substrate W in the vertical direction Z. Here, when foreign matter is present on the conveyed substrate W, the protection member 6B1 vibrates due to contact with the protection member 6B1, and the vibration sensor 6B2 detects the vibration and outputs it to the control unit 9. The control unit 9 detects whether or not a foreign substance is present on the substrate W based on the vibration detected by the vibration sensor 6B2. The foreign matter detection mechanism 6B (=protection member 6B1+vibration sensor 6B2) continues the foreign matter detection until the rear end of the substrate W passes through the foreign matter detection mechanism 6B (step S25). Thus, the foreign matter is detected in the vertical direction on the entire surface Wf of the substrate W.

Even when a foreign substance is detected in the foreign substance detection from the vertical direction, the control unit 9 forcibly stops the conveyance of the substrate W and interrupts the coating process, as in the case of detecting the foreign substance from the horizontal direction. On the other hand, when no foreign matter is detected, the transport of the substrate W is continued until the substrate W reaches the coating start position, the substrate W is positioned at the coating start position, and the transport of the substrate W is stopped for a certain period of time (step S13). This "coating start position" is for supplying the coating liquid ejected from each slit nozzle 511 to the surface Wf of the substrate W first while the substrate W is stationary to form a bead (a liquid pool on the substrate W). Means the position of the substrate W in the transport direction X. Since the coating device 1 is a device that forms two coating blocks by the two coating mechanisms 5A and 5B, the position of the substrate W in the transport direction X when the front surface Wf of the substrate W faces the two ejection ports 511a. Corresponds to the “application start position”. Specifically, at the time when the front end of the substrate W is located directly below the slit nozzle 511 of the downstream coating mechanism 5B and the substantially central portion of the substrate W is located directly below the slit nozzle 511 of the upstream coating mechanism 5A. The position of the substrate W in the transport direction X is the “coating start position”.

While the substrate transfer is stopped, the upstream coating mechanism 5A and the downstream coating mechanism 5B respectively pump the coating liquid from a coating liquid supply mechanism (not shown), and as shown in FIG. 6C, discharge a small amount of the coating liquid. The beads B are formed by simultaneously supplying from the surface 511a to the front surface Wf of the substrate W (steps S26 and S34). Then, the conveyance of the substrate W is restarted after the formation of the beads B (step S14), and the ejection amount of the coating liquid from each ejection port 511a is increased to a predetermined amount (steps S27, S35), as shown in FIG. 6D. Coating blocks CBa and CBb formed by coating the coating liquid on the surface Wf of the substrate W are formed.

When the coating blocks CBa and CBb having a desired size are formed, the upstream coating mechanism 5A and the downstream coating mechanism 5B stop discharging the coating liquid (steps S28 and S36). Here, in the present embodiment, the ejection of the coating liquid is stopped at the same time to form the coating blocks CBa and CBb of the same size. However, when the lengths in the transport direction X are different from each other, the ejection of the coating liquid is stopped. The timing may be different from each other. When the coating process is completed in this way, in the upstream coating mechanism 5A and the downstream coating mechanism 5B, after the slit nozzle 511 is raised to the cleaning standby position, the process returns to steps S21 and S31 to execute nozzle cleaning and liquid pool formation, and Preparation for the coating process is performed.

In parallel with such nozzle cleaning and the like, the substrate W on which the coating blocks CBa and CBb are formed is transported to the downstream levitation unit 3C. Then, the conveyance of the substrate W is stopped by the downstream levitation unit 3C (step S15). Further, after releasing the suction of the substrate W by the chuck portion 41, the substrate W is lifted from the chuck portion 41 by lift pins (not shown). Further, the substrate W is carried out of the coating apparatus 1 by a transfer robot (not shown).

As described above, in the present embodiment, the two slit nozzles 511 are arranged in the transport direction X of the substrate W at a constant interval L, and each slit is provided while the transport of the substrate W is temporarily stopped. The bead B is formed by ejecting the coating liquid from the nozzle 511. Subsequently, the transfer of the substrate W is restarted, and the coating liquid is discharged during the transfer of the substrate. As a result, the two coating blocks CBa and CBb are formed in parallel in the transport direction X of the substrate W so as to be separated from each other. Therefore, it is possible to effectively suppress the occurrence of unevenness in the transport mechanism, which has been a problem in the conventional technique of sequentially forming a plurality of coating blocks. As a result, the two coating blocks CBa and CBb can be formed well. Further, it is possible to form the two coating blocks CBa and CBb with higher work efficiency than the conventional technique.

Many of the substrates W on which the two coating blocks CBa and CBb are formed are so-called multi-chambered substrates, and have coating blocks CBa in the non-coating regions formed between the coating blocks CBa and CBb. It is divided into a small substrate and a small substrate having a coating block CBb. On the other hand, by applying the entire surface Wf of the substrate W and then dividing the substrate W into two, it is possible to create two small substrates in the same manner as described above. It is also necessary to apply the coating liquid. Therefore, according to the present embodiment, there is also an effect that the usage amount of the coating liquid can be reduced.

Further, in the present embodiment, since two types of foreign matter detection mechanisms 6A and 6B different from each other are provided and the foreign matter detection is performed in a multifaceted manner, the foreign matter can be detected on the substrate W more reliably. Since the coating process is performed only on the substrate W for which no foreign matter is detected by any of the foreign matter detection mechanisms 6A and 6B, a high quality coating process can be performed. Here, the non-contact type foreign substance detection (detection by the foreign substance detection mechanism 6A) and the contact type foreign substance detection (detection by the foreign substance detection mechanism 6B) are combined, but these combinations are arbitrary. Further, as the contact type foreign matter detection, a sensor other than the vibration sensor, for example, a contact type sensor described in JP 2011-212544 A may be used.

As described above, in the present embodiment, the front surface Wf and the back surface Wb of the substrate W correspond to the “other main surface of the substrate” and the “one main surface of the substrate” of the present invention, respectively. The slit nozzle 511 corresponds to an example of the "nozzle" in the present invention. Further, the space SP corresponds to an example of the “floating space” 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, two slit nozzles 511 are provided and two coating blocks CBa and CBb are formed in parallel, but M (M≧3) slit nozzles are arranged in the transport direction X of the substrate W. However, M coating blocks may be formed in parallel.

Further, in the above-described embodiment, the present invention is applied to the coating device 1 including two types of foreign matter detection mechanisms, but the present invention is also applied to a coating device including only one of them. You can

Further, in the above-described embodiment, the present invention is applied to the coating device that performs the coating process using the slit nozzle 511 having the slit shape, but to the coating device that performs the coating process using the nozzle having an opening other than the slit shape. However, the present invention can be applied.

Further, in the above embodiment, the central levitation unit 3B is configured by providing the precision levitation units 3B1 and 3B3 facing each other for each ejection port 511a of the slit nozzle 511 and the normal levitation unit 3B2 independently of each other. However, the central levitation unit 3B is configured by a single precision levitation unit in which ejection holes and suction holes are provided on the entire surface of one plate-shaped stage surface extending from the upstream side slit nozzle 511 to the downstream side slit nozzle 511. You may.

INDUSTRIAL APPLICABILITY The present invention can be applied to all coating techniques in which a coating liquid is applied to the other main surface of a substrate while the substrate is being conveyed in the transfer direction while a gas is blown onto the one main surface of the substrate to float the substrate.

DESCRIPTION OF SYMBOLS 1... Coating device 3... Levitation mechanism 3A... Upstream levitation unit 3B... Central levitation unit 3C... Downstream levitation unit 3B1, 3B3... Precision levitation unit 4... Conveying mechanism 5A... Upstream coating mechanism 5B... Downstream coating mechanism 34a... Spout hole 34b... Suction hole 51... Nozzle unit 52... Nozzle cleaning standby unit 511... Slit nozzle 511a... (Slit nozzle) discharge ports CBa, CBb... Coating block SP... (Floating) space X... Transport direction W... Substrate Wb... Backside (of substrate) On the other hand)
Wf... front surface (other main surface of substrate)

Claims (6)

A levitation mechanism that blows gas onto one main surface of the substrate to levitate the substrate,
A transport mechanism that intermittently transports the substrate floated by the levitation mechanism in a transport direction,
A plurality of nozzles having a discharge port for discharging a coating liquid on the other main surface of the substrate floated by the levitation mechanism,
The transfer mechanism transfers the substrate to a coating start position where the other main surface of the substrate faces the plurality of ejection ports, and temporarily stops the transfer of the substrate at the coating start position, and then transfers the substrate. Restarting the transfer of the substrate in the direction,
The plurality of nozzles are arranged in the transfer direction, start discharging the coating liquid from the discharge port while temporarily stopping the transfer of the substrate, and transfer the substrate in the transfer direction. A coating device, wherein a plurality of coating blocks are formed on the other main surface of the substrate by continuing to discharge the coating liquid from the discharge port. The coating apparatus according to claim 1, wherein
The levitation mechanism includes a central levitation unit including a precision levitation unit provided facing each discharge port, an upstream levitation unit provided adjacent to the central levitation unit on the upstream side in the conveyance direction, and a levitation mechanism in the conveyance direction. A downstream levitation unit provided adjacent to the central levitation unit on the downstream side,
A coating apparatus in which the accuracy of floating the substrate by the upstream floating unit and the downstream floating unit is lower than the accuracy of floating the substrate by the precision floating unit. The coating device according to claim 2, wherein
The precision floating portion is provided independently for each of the discharge ports,
Each of the precision levitation units has a spraying hole for blasting gas into a levitation space formed between the levitation space and one main surface of the substrate, and a suction hole for sucking gas from the levitation space. The coating device according to any one of claims 1 to 3,
The plurality of nozzles are coating devices that simultaneously discharge the coating liquid from the discharge ports. The coating device according to any one of claims 1 to 4,
Each of the discharge ports has a slit shape extending in a direction orthogonal to the transport direction so as to face the other main surface of the substrate. A coating liquid ejected from the ejection port of the nozzle is applied to the other main surface of the substrate while intermittently conveying the substrate in the conveying direction in a state where the gas is blown to one main surface of the substrate to float the substrate. A coating method,
Arranging a plurality of the nozzles in the carrying direction,
A step of transporting the substrate to a coating start position where the other main surface of the substrate faces discharge ports of the plurality of nozzles, and temporarily stopping the transport of the substrate at the coating start position;
After the ejection of the coating liquid from the plurality of ejection ports is started while the conveyance of the substrate is stopped, the substrate is moved in the conveyance direction while continuing the ejection of the coating liquid from the ejection ports. A step of restarting the conveyance to form a plurality of coating blocks on the other main surface of the substrate,
A coating method comprising:

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