CN115739522B - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

The invention aims to prevent a nozzle guard integrally lowered with a slit nozzle from stepping on a protrusion to adversely affect the application of a processing liquid to a substrate. The invention provides a substrate processing apparatus and a substrate processing method. The invention comprises the following steps: a slit nozzle having a slit-shaped discharge port; a moving mechanism for relatively moving the slit nozzle with respect to the substrate; a nozzle guard disposed on a front side of the slit nozzle in a nozzle traveling direction in which the slit nozzle travels relatively to the substrate by the moving mechanism, and integrally moved with the slit nozzle; a lifting mechanism for lifting the slit nozzle and the nozzle guard integrally; and a collision detection unit for detecting that the tip of the nozzle guard lowered by the lifting mechanism protrudes upward on the surface side of the substrate and collides with a protrusion that blocks the application of the processing liquid.

Description

Substrate processing apparatus and substrate processing method

Technical Field

The present invention relates to a substrate processing technique for supplying a processing liquid from a slit nozzle to and coating a substrate for precision electronic devices such as a glass substrate for a flat panel display (FLAT PANEL DISPLAY, FPD) such as a liquid crystal display device or an organic EL display device, a semiconductor wafer, a glass substrate for a photomask, a substrate for a color filter, a substrate for a recording disk, a substrate for a solar cell, a substrate for electronic paper, and a substrate for a semiconductor package (hereinafter, simply referred to as "substrate"), and particularly relates to a substrate processing apparatus and a substrate processing method.

Background

There is known a substrate processing apparatus that applies a processing liquid to a substrate by relatively moving a slit nozzle having a slit-shaped discharge port with respect to the substrate and discharging the processing liquid from the slit nozzle. For example, in the apparatus described in patent document 1, a slit nozzle is moved above a stage surface of a stage in a state where a substrate is held on the stage surface, and a processing liquid is applied. On the other hand, in the apparatus described in patent document 2, the substrate is moved in a so-called floating manner in a state where the slit nozzle is positioned at a predetermined coating position above the stage surface of the stage. More specifically, the substrate is floated by a pressure gas layer formed on the platen surface by a gas flow passing through a gas hole provided in the platen surface, and the substrate is moved so as to pass through a coating region sandwiched between the slit nozzle and the platen surface, thereby coating the processing liquid. In this way, although the substrate is conveyed in different ways, a nozzle guard is provided in any device. This is considered to be that foreign matter, bumps, or the like may protrude upward on the surface side of the substrate. That is, if the coating of the treatment liquid is performed in a state where the protrusions are present, the slit nozzle collides with the protrusions, thereby impeding the coating of the treatment liquid. That is, the collision may adversely affect the applied treatment liquid or the slit nozzle. In the conventional device, therefore, the nozzle guard is disposed on the front side of the slit nozzle in the nozzle traveling direction in which the slit nozzle travels relative to the substrate.

[ Prior Art literature ]

[ Patent literature ]

Patent document 1 Japanese patent laid-open No. 2006-102609

Patent document 2 japanese patent laid-open publication No. 2011-212544

Disclosure of Invention

[ Problem to be solved by the invention ]

In the substrate processing apparatus, before the slit nozzle is moved relatively to the substrate to perform the coating process, the slit nozzle is lowered from a position away from the substrate upward to a coating position so that the discharge port is positioned near the surface of the substrate. At this time, the nozzle guard lifted integrally with the slit nozzle is also lifted integrally with the slit nozzle, and the tip (lower end) of the nozzle guard is located near the surface of the substrate. If a projection such as a foreign matter or a bump is present at a position immediately below the nozzle guard, the nozzle guard may collide with the projection from above and tread on the projection.

However, in the prior art, detection of the tread is not considered. That is, there is a case where the presence of the protrusion cannot be detected, and in a state where the protrusion is stepped on, the nozzle guard may be moved integrally with the slit nozzle with respect to the substrate. As a result, the substrate or the slit nozzle may be adversely affected.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a substrate processing apparatus and a substrate processing method, which can prevent a problem that a nozzle guard integrally lowered with a slit nozzle steps on a projection and adversely affects the application of a processing liquid to a substrate in advance.

[ Means of solving the problems ]

An embodiment of the present invention is a substrate processing apparatus that applies a processing liquid on a surface of a substrate, and includes: a slit nozzle (slit nozzle) having a slit-shaped discharge port; a moving mechanism for relatively moving the slit nozzle with respect to the substrate; a nozzle guard (nozzle guard) disposed on the front side of the slit nozzle in the nozzle traveling direction in which the slit nozzle travels relatively to the substrate by the moving mechanism, and moving integrally with the slit nozzle; a lifting mechanism for lifting the slit nozzle and the nozzle guard integrally; and a collision detection unit (collision detector) that detects (detect) that the tip of the nozzle guard that is lowered by the lifting mechanism protrudes upward on the front surface side of the substrate and collides with the protrusion that blocks the application of the processing liquid.

Another embodiment of the present invention is a substrate processing method of applying a processing liquid to a surface of a substrate by relatively moving a slit nozzle with respect to the substrate while discharging the processing liquid from the discharge port in a state where the discharge port of the slit nozzle is close to the surface of the substrate, the substrate processing method including: a lowering step of lowering the slit nozzle integrally with a nozzle guard disposed on a front side of the slit nozzle in a nozzle traveling direction in which the slit nozzle travels relatively to the substrate, so that the discharge port approaches the surface of the substrate; and a collision detection step of detecting whether or not the tip of the nozzle guard protrudes upward on the surface side of the substrate in the lowering step and collides with the protrusion that impedes the application of the processing liquid.

In the invention thus constituted, the nozzle guard is also integrally lowered during the lowering of the slit nozzle. Here, if there is a protrusion on the lower side of the nozzle guard, the front end of the nozzle guard collides with the protrusion and steps on. The term "protrusion" as used herein refers to a foreign substance attached to the surface of a substrate, a ridge formed by a part of the substrate protruding upward, or the like, and means an object that becomes a factor of obstructing the application of the treatment liquid when the application of the treatment liquid is continued in a state where the nozzle guard is stepped on. Therefore, in the present invention, the tip of the nozzle guard is configured to be able to detect collision with the projection projecting upward on the surface side of the substrate during the descent.

[ Effect of the invention ]

As described above, according to the present invention, it is possible to prevent the nozzle guard integrally lowered with the slit nozzle from stepping on the protrusion and adversely affecting the application of the processing liquid to the substrate.

Drawings

Fig. 1 is a diagram schematically showing the overall configuration of a coating apparatus as a first embodiment of a substrate processing apparatus according to the present invention.

Fig. 2A is a plan view of the floating portion.

Fig. 2B is a side view schematically showing the relationship between the floating portion and the coating mechanism.

Fig. 3 is a perspective view showing the overall structure of a slit nozzle and a nozzle guard used in the substrate processing apparatus shown in fig. 1.

Fig. 4 is a side view of the slit nozzle and nozzle guard viewed from the width direction.

Fig. 5 is a diagram showing an example of a conventional substrate processing apparatus.

Fig. 6 is a flowchart showing a coating operation performed by the coating apparatus shown in fig. 1.

Fig. 7 is a partially enlarged view of a second embodiment of the substrate processing apparatus of the present invention.

Fig. 8 is a partially enlarged view of a third embodiment of the substrate processing apparatus of the present invention.

Fig. 9A is a partially enlarged view of a fourth embodiment of the substrate processing apparatus of the present invention.

Fig. 9B is a partially enlarged view of a fourth embodiment of the substrate processing apparatus of the present invention.

Fig. 10 is a partially enlarged view of a fifth embodiment of the substrate processing apparatus of the present invention.

Fig. 11 is a partially enlarged view of a sixth embodiment of the substrate processing apparatus of the present invention.

[ Description of symbols ]

1: Coating device (substrate processing device)

2: Input transfer unit

3: Floating part

3A: upstream floating platform (floating platform)

3B: central floating platform (Floating platform)

3C: downstream floating platform (floating platform)

4: Output transfer unit

5: Substrate conveying part

7: Coating mechanism

8: Nozzle driving mechanism

9: Control unit

21. 41, 101, 111: Roller conveyor

22. 42: Rotation/lifting driving mechanism

31. 34A: spray hole (gas hole)

33: Flat table top

34: Lifting pin driving mechanism

34B: suction hole (gas hole)

35: Floating control mechanism

51: Chuck mechanism

52: Adsorption/travel control mechanism (moving mechanism)

61: Sensor for detecting a position of a body

71: Slit nozzle

72: Nozzle guard

73: Guard support

74: Supporting shaft

75: Spring

76: Stop piece

79: Nozzle cleaning standby unit

91: Calculation unit

92: Storage unit

93: Fixed disk

94: Display unit

95: Input unit

100: Input conveyor

102. 112: Rotary driving mechanism

110: Output conveyor

351: Compression mechanism

352: Temperature regulating unit

353A: air supply unit (upstream air supply unit)

353A: filter device

353B: air supply unit (Central air supply unit)

353B: needle valve

353C: air supply unit (downstream air supply unit)

353C: flowmeter for measuring flow rate

353D, 354b: pressure gauge (collision detecting part, pressure measuring part)

353E: pneumatic valve

354: Air suction part

354A: blower fan

354C: relief valve

701: Stress detecting sensor (Collision detecting part)

702: Vibration sensor (collision detecting part)

703: Position sensor (collision detecting part)

704: Angle detecting sensor (Collision detecting part)

705: Floating amount measuring unit (collision detecting unit)

705A, 705b: displacement meter (Collision detecting part)

711: Discharge port (of slit nozzle)

721: Long hole

791: Roller

792: Cleaning part

793: Roller bar

Dt: direction of conveyance

Pc: coating position (position)

PS1, PS2: projections

S: substrate board

S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S51, S52, S53, S54: step (a)

Sb: back surface

Sf: surface (of substrate)

SP: space of

X: direction of

Y: horizontal direction (direction)

Z: in the up-down direction

Θa, θb: angle of

Detailed Description

< First embodiment >, first embodiment

Fig. 1 is a diagram schematically showing the overall configuration of a coating apparatus as a first embodiment of a substrate processing apparatus according to the present invention. The coating apparatus 1 is a slit coater that applies a coating liquid on a surface Sf of a substrate S conveyed in a horizontal posture from the left-hand side to the right-hand side in fig. 1. For example, the coating apparatus 1 can be suitably used for the purpose of forming a uniform coating film by coating a coating liquid containing a material for a resist film, a coating liquid containing an electrode material, or other various processing liquids on the surface Sf of various substrates S such as a glass substrate or a semiconductor substrate.

In the following drawings, in order to clarify the arrangement relation of the respective units of the apparatus, right-handed XYZ orthogonal coordinates are set as shown in fig. 1. The conveyance direction of the substrate S is referred to as an "X direction", a horizontal direction from the left-hand side to the right-hand side in fig. 1 is referred to as a "+x direction", and the opposite direction is referred to as a "—x direction". Among the horizontal directions Y orthogonal to the X direction, the front side of the device (the near front side in the drawing) is referred to as the "-Y direction", and the back side of the device is referred to as the "+y direction". Further, the upper direction and the lower direction in the vertical direction Z are referred to as "+z direction" and "—z direction", respectively.

First, the outline of the structure and operation of the coating apparatus 1 will be described with reference to fig. 1, and thereafter, the structure and operation of the collision detecting section including the technical features of the present invention will be described. In the coating apparatus 1, the input conveyor 100, the input transfer unit 2, the floating unit 3, the output transfer unit 4, and the output conveyor 110 are arranged in this order along the conveyance direction Dt of the substrate S, that is, in the +x direction, and as described in detail below, a conveyance path of the substrate S extending in the substantially horizontal direction is formed by these members.

The substrate S to be processed is carried into the input conveyor 100 from the left-hand side in fig. 1. The input conveyor 100 includes a roller conveyor (roller conveyor) 101 and a rotation driving mechanism 102 that rotationally drives the roller conveyor 101, and conveys the substrate S in a horizontal posture toward the downstream side, 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 the roller conveyor 21. The substrate S is further conveyed in the (+ X) direction by rotating the roller conveyor 21. The vertical position of the substrate S is changed by lifting and lowering the substrate S by the roller conveyor 21. The substrate S is transferred from the input conveyor 100 to the floating unit 3 by the input transfer unit 2 configured as described above.

Fig. 2A is a plan view of the floating portion, and fig. 2B is a side view schematically showing a relationship between the floating portion and the coating mechanism. In these drawings, the entire central floating platform 3B and a part of the upstream floating platform 3A and the downstream floating platform 3C out of the three platforms constituting the floating portion 3 are schematically shown.

The upstream floating platform 3A and the downstream floating platform 3C are each formed with a plurality of air discharge holes 31 dispersed in a matrix on the entire surface of a single plate-like platform surface 33. Then, compressed air is supplied to each of the ejection holes 31, and the substrate S is lifted by the flow of gas generated by the ejection of the compressed air from each of the ejection holes 31. Thus, the substrate S floats from the stage surface 33 to a predetermined floating height, for example, 10 to 500 μm in the upstream floating stage 3A and the downstream floating stage 3C. In order to supply compressed air to each of the discharge holes 31, as shown in fig. 1 and 2B, a floating control mechanism 35 is provided. The floating control mechanism 35 will be described after three floating platforms 3A to 3C are described.

Although illustration of fig. 2A and 2B is omitted, the downstream floating platform 3C has a plurality of lift pins in addition to the discharge holes 31. In addition, as shown in fig. 2B, in order to raise and lower the lift pin, a lift pin driving mechanism 34 is provided. The plurality of lift pins are provided so as to be capable of facing the entire rear surface Sb of the substrate S with a predetermined interval therebetween by spacing the gap between the ejection holes 31. The lift pins are driven to move up and down in the vertical direction (Z-axis direction) by a lift pin driving mechanism 34 provided below the platform surface 33. That is, the tip of the lift pin is lowered in the (-Z) direction side of the platform surface 33 of the downstream floating platform 3C during lowering, and the tip of the lift pin is raised to a position where the substrate S is transferred to the transfer robot (not shown) during raising. The lower surface of the substrate S is supported and lifted by the lift pins thus lifted, and therefore the substrate S is lifted from the stage surface 33 of the downstream floating stage 3C. This enables the substrate S to be unloaded from the coating apparatus 1 by the transfer robot.

On the other hand, the center floating platform 3B is configured to have a higher floating accuracy than the upstream floating platform 3A and the downstream floating platform 3C. That is, the center floating platform 3B has a rectangular plate-like platform surface 33. The land surface 33 has a plurality of holes dispersed in a matrix at a pitch narrower than the discharge holes 31 provided in the upstream floating land 3A and the downstream floating land 3C. In addition, unlike the upstream floating platform 3A and the downstream floating platform 3C, in the center floating platform 3B, one half of the holes functions as the compressed air discharge holes 34a, and the other half functions as the suction holes 34B. That is, compressed air is discharged from the discharge holes 34a toward the rear surface Sb of the substrate S and is fed into the space SP (fig. 2B) between the mesa 33 and the rear surface Sb of the substrate S. On the other hand, the air is sucked from the space SP through the suction holes 34 b. By ejecting and sucking air from the space SP as described above, in the space SP, after the gas flow of the compressed air ejected from each ejection hole 34a expands in the horizontal direction, the air is sucked from the suction hole 34b adjacent to the ejection hole 34a, and the pressure balance in the air layer (pressure gas layer) expanded to the space SP becomes more stable, so that the floating height of the substrate S can be controlled with high accuracy and stability. The supply of compressed air to the discharge holes 34a and the suction of air from the suction holes 34b are controlled by a floating control means 35 described below.

The floating control means 35 has a supply passage and a suction passage for air in the three floating platforms 3A to 3C. As shown in fig. 2B, after the air compressed by the compressor compression mechanism 351 reaches a predetermined temperature by the temperature adjustment unit 352, the air supply passage branches into three and is supplied to each of the floating platforms 3A to 3C. The temperature adjustment means 352 sets the air to a predetermined temperature so as to maintain the air in a constant temperature state regardless of the outside air temperature. The branched air is pressure-fed to the floating platform 3A to the floating platform 3C via the upstream air supply unit 353A, the central air supply unit 353B, and the downstream air supply unit 353C, respectively. The three air supply portions 353A to 353C have the same configuration, but are individually controlled by the control unit 9. Specifically, the air supply units 353A to 353C are purged through the filter 353A, the pressure is adjusted by the needle valve 353b, and then the pressure is fed to the discharge hole 34a through the flowmeter 353C, the manometer 353d, and the air-operated valve (air operation valve) 353 e. The start and stop of the supply of air are performed by opening and closing the air-operated valve 353e by a command signal from the control unit 9 (fig. 1). In each of the air supply units 353A to 353C, the pressure in the supply passage can be measured by the pressure gauge 353 d. The control unit 9 performs pressure control of the compressed air based on the measurement result of the manometer 353 d.

In addition, in the floating control mechanism 35, an air suction portion 354 is provided for sucking air from the suction hole 34 b. In the air suction portion 354, a blower 354a is used as a suction means for air, and a driving motor (not shown) is inverter-controlled. A pressure gauge 354B is provided in a suction flow path from a suction hole 34B provided in the platform surface 33 of the center floating platform 3B, and the pressure in the suction flow path can be measured. In addition, a release valve 354c is provided in the suction flow path. Thus, when the pressure in the suction passage is higher than the suction pressure obtained by the rotation of the blower 354a, the air in the suction passage is discharged to the outside from the release valve 354c, and thus fine adjustment for maintaining the pressure in the suction passage at a constant level can be performed.

The description is continued with reference back to fig. 1. The substrate S carried into the floating unit 3 via the input transfer unit 2 is given a pushing force in the (+ X) direction by the rotation of the roller conveyor 21, and is carried onto the upstream floating platform 3A. The upstream floating platform 3A, the center floating platform 3B, and the downstream floating platform 3C support the substrate S in a floating state, but do not have a function of moving the substrate S in the horizontal direction. The substrate S in the floating unit 3 is transported by the substrate transport unit 5 disposed below the upstream floating platform 3A, the center floating platform 3B, and the downstream floating platform 3C.

The substrate conveying section 5 includes: a chuck mechanism 51 partially abutting on a lower surface edge portion of the substrate S, thereby supporting the substrate S from below; and a suction/travel control mechanism 52 having a function of applying negative pressure to a suction pad (not shown) of a suction member provided at an upper end of the chuck mechanism 51 to suction and hold the substrate S and a function of reciprocating the chuck mechanism 51 in the X direction. In a state where the chuck mechanism 51 holds the substrate S, the back surface Sb of the substrate S is located at a position higher than the surface of each stage of the floating portion 3. Therefore, the substrate S is held by the chuck mechanism 51 by suction at the edge portion, and the entire substrate S maintains a horizontal posture by the buoyancy given by the floating portion 3. Further, in order to detect the vertical position of the surface of the substrate S while the back surface Sb of the substrate S is partially held by the chuck mechanism 51, a sensor 61 for measuring the plate thickness is disposed in the vicinity of the roller conveyor 21. A chuck (not shown) that does not hold the substrate S is located at a position immediately below the sensor 61, and the sensor 61 can thereby detect the vertical position of the suction surface, which is the surface of the suction member.

The chuck mechanism 51 holds the substrate S carried in from the input transfer unit 2 to the floating unit 3, and in this state, the chuck mechanism 51 moves in the (+ X) direction, thereby carrying the substrate S from above the upstream floating platform 3A to above the downstream floating platform 3C via above the central floating platform 3B. The transported substrate S is delivered to the output transfer unit 4 disposed on the (+ X) side of the downstream floating platform 3C.

The output transfer unit 4 includes a roller conveyor 41 and a rotation/elevation drive mechanism 42 having a function of rotationally driving the roller conveyor 41 and a function of elevating the roller conveyor 41. The roller conveyor 41 rotates to apply a pushing force in the (+ X) direction to the substrate S, and further conveys the substrate S along the conveying direction Dt. The roller conveyor 41 is lifted and lowered to change the vertical position of the substrate S. The substrate S is transferred from the upper side of the downstream floating platform 3C to the output conveyor 110 by the output transfer unit 4.

The output conveyor 110 includes a roller conveyor 111 and a rotation driving mechanism 112 that rotationally drives the roller conveyor 111, and conveys the substrate S further in the (+ X) direction by the rotation of the roller conveyor 111 and finally discharges the substrate S to the outside of the coating apparatus 1. The input conveyor 100 and the output conveyor 110 may be provided as a part of the structure of the coating apparatus 1, but may be separate from the coating apparatus 1. In addition, for example, a substrate discharge mechanism of another unit provided on the upstream side of the coating apparatus 1 may be used as the input conveyor 100. In addition, a substrate receiving mechanism of another unit provided on the downstream side of the coating apparatus 1 may also be used as the output conveyor 110.

Fig. 3 is a perspective view showing the overall structure of a slit nozzle and a nozzle guard used in the substrate processing apparatus shown in fig. 1. Fig. 4 is a side view of the slit nozzle and nozzle guard viewed from the width direction. The coating mechanism 7 for coating the surface Sf of the substrate S with the coating liquid is disposed on the conveyance path of the substrate S conveyed as described above. The coating mechanism 7 has a slit nozzle 71. As shown in fig. 1, a nozzle driving mechanism 8 is connected to the slit nozzle 71, and the slit nozzle 71 is positioned at an application position (a position Pc shown by a solid line in fig. 1 and 4) above the center floating platform 3B, an upper position (a position shown by a one-dot chain line in fig. 4) away from the application position, or a maintenance position by the nozzle driving mechanism 8. Further, a coating liquid supply mechanism, not shown, is connected to the slit nozzle 71, and the coating liquid is supplied from the coating liquid supply mechanism and discharged as a treatment liquid from a discharge port 711 opening downward at the lower part of the nozzle.

The discharge port 711 of the slit nozzle 71 is provided so as to extend in the Y direction, and is supported by a nozzle support (not shown) so as to be capable of discharging the coating liquid downward (toward the (-Z side). The nozzle support is connected to a nozzle driving mechanism 8. In particular, when the coating liquid is supplied to the surface Sf of the substrate S by the slit nozzle 71, the slit nozzle 71 moves to a position above the coating position Pc as indicated by a one-dot chain line in fig. 4, and then descends until the interval (gap) between the discharge port 711 and the substrate S reaches a predetermined value. Thereby, the slit nozzle 71 is positioned at the coating position Pc. Thereafter, the coating liquid is discharged from the discharge port 711 toward the surface Sf of the substrate S in the aligned state, and the substrate S is conveyed in the (+ X) direction. That is, the slit nozzle 71 moves relatively in the (-X) direction with respect to the substrate S to perform the coating process. That is, in the present embodiment, the (-X) direction corresponds to the "nozzle traveling direction" of the present invention.

In order to perform predetermined maintenance on the slit nozzle 71 thus configured, as shown in fig. 1, a nozzle cleaning standby unit 79 is provided in the coating mechanism 7. The nozzle cleaning standby unit 79 mainly includes a roller 791, a cleaning portion 792, a roller bar 793, and the like. In a state where the slit nozzle 71 has been positioned at the maintenance position, the nozzle cleaning or preliminary discharge processing is suitably performed by these members, and the discharge opening of the slit nozzle 71 is adjusted to a state suitable for the next coating processing.

In the coating process, if the projections such as the foreign matters and the bumps present on the front surface side of the substrate S move to the coating position Pc and reach the slit nozzle 71 along with the substrate conveyance as described above, the coated coating liquid or the slit nozzle 71 may be adversely affected. Accordingly, a nozzle guard 72 is attached to the slit nozzle 71.

Here, as the nozzle guard 72, for example, as shown in fig. 5, a nozzle guard equipped in the apparatus described in patent document 1 may be used. That is, the nozzle guard 72 includes a long, non-transparent material having a non-flexibility and a length longer than the Y-direction dimension of the substrate S, and a relatively hard material member having a degree of not being broken even when it is in contact with a projection such as a metal or a ceramic. As shown in fig. 5, the nozzle guard 72 is supported by a guard support 73 extending from the slit nozzle 71 in the (-X) direction. More specifically, the nozzle guard 72 is supported on the guard support 73 via a support shaft 74 in the Y direction so as to be swingable on the XZ plane about the support shaft 74. That is, the position where the support shaft 74 is provided corresponds to the "shaft fulcrum" of the present invention.

The rear end portion of the nozzle guard 72, that is, the portion above the support shaft 74 is biased toward the (-X) direction by the spring 75, and the front end portion of the nozzle guard 72, that is, the portion below the support shaft 74 is restricted from rotating toward the (-X) direction by the stopper 76. Thus, the tip of the nozzle guard 72 is configured to be rotatable in the (+x) direction only on the (-X) direction side (the front side of the slit nozzle 71 in the nozzle traveling direction of the slit nozzle 71 in the coating process). Therefore, in the non-contact state of the nozzle guard 72 and the protrusion PS2, the nozzle guard 72 is held in a state along the vertical direction Z by the urging force generated by the spring 75. On the other hand, when the nozzle guard 72 is in contact with the protrusion PS2 in the coating process, the front end of the nozzle guard 72 is relatively rotationally moved to the (+x) direction side with respect to the slit nozzle 71 against the urging force generated by the spring 75. By detecting the rotational movement by a rotation detection sensor (not shown), the presence of the protrusion PS1 can be detected before the protrusion PS1 reaches the slit nozzle 71.

However, as shown by the broken line in fig. 5, if the projection PS2 exists at or near the coating position Pc, the above-described problem may occur. That is, when the slit nozzle 71 is lowered until the interval (gap) between the discharge port 711 and the substrate S reaches a predetermined value, the nozzle guard 72 is also lowered, and the tip thereof sometimes collides with the protrusion PS2 from above and steps on. However, in the conventional structure shown in fig. 5, the tread cannot be detected.

In the present embodiment, therefore, a stress detection sensor 701 such as a load cell is additionally mounted to the nozzle guard 72 as an example of the "collision detection portion" of the present invention, as compared with the conventional structure shown in fig. 5. In more detail, as shown in fig. 4, when the tip of the nozzle guard 72 collides with the protrusion PS2 during the descent integrally with the slit nozzle 71, the stress detection sensor 701 detects the stress applied to the nozzle guard 72, and outputs a signal to the control unit 9 that the protrusion PS2 is stepped on. In addition, regarding the protrusion PS1 (fig. 5) existing at a position distant from the application position Pc, a signal indicating that the protrusion PS1 is detected is output from the rotation detection sensor to the control unit 9 in the same manner as in the conventional art.

In order to control each part of the coating apparatus 1 configured as described above, a control unit 9 is provided. As shown in fig. 1, the control unit 9 is configured as a general computer system in which an arithmetic unit 91 (for example, a central processing unit (Central Processing Unit, CPU)) that performs various arithmetic processes, a storage unit 92 (for example, a Read Only Memory (ROM) or a random access Memory (Random Access Memory, RAM)) that stores a basic program and various information, and the like are connected to a bus. The bus is also connected to a fixed disk 93 (for example, a hard disk drive) for storing a coating program or the like, a display unit 94 (for example, a display or the like) for displaying various information, and an input unit 95 (for example, a keyboard, a mouse, or the like) for receiving an input from an operator. For example, a touch panel display or the like in which the functions of the display portion 94 and the input portion 95 are integrated may be used. Further, the operation unit 91 of the control unit 9 receives signals transmitted from the stress detection sensor 701, the rotation detection sensor, and the like via an interface, not shown, and controls the respective units according to a coating program, thereby executing a coating process described below.

Fig. 6 is a flowchart showing a coating operation performed by the coating apparatus shown in fig. 1. In the coating apparatus 1, the slit nozzle 71 used in the coating process is moved to the maintenance position to perform the preliminary discharge process. In addition, the ejection and suction of the compressed air in the floating section 3 are started, and the carried-in substrate S can be prepared to be floated (step S1). Further, the slit nozzle 71 may be cleaned before the preliminary discharge process.

Next, the substrate S starts to be carried into the coating apparatus 1 (step S2). The substrate S to be processed is placed on the input conveyor 100 by another processing unit, a transfer robot, or the like on the upstream side, and is transferred in the (+ X) direction by rotation of the roller conveyor 101. The substrate S is transported to the upper portion of the upstream floating platform 3A which gives buoyancy to the substrate S by the discharge of compressed air by cooperation of the input transfer unit 2 positioned at the same height position as the roller conveyor 101 of the input conveyor 100 on the upper surfaces of the input conveyor 100 and the roller conveyor 21. When the substrate S is carried into the upstream floating platform 3A, the lift pins provided on the upstream floating platform 3A are positioned at upper positions where the upper ends thereof protrude above the upper surface of the upstream floating platform 3A by the lift pin driving mechanism 34. Thereby, the substrate S, more specifically, both ends in the Y direction of the substrate S, which the lift pins are in contact with, are lifted.

Then, the chuck mechanism 51 moves in the (-X) direction and moves to the transport start position immediately below the substrate S (step S3). Immediately thereafter, the substrate S is transferred to the chuck mechanism 51. Immediately thereafter, the chuck mechanism 51 suctions and holds the edge portion of the substrate S, and moves in the (+ X) direction in this state. Thereby, the substrate S is conveyed to the coating position Pc (step S4). In parallel with this, the slit nozzle 71 is moved from the preliminary discharge position to the application position Pc (step S5). More specifically, as shown by the one-dot chain line in fig. 4, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the descent of the slit nozzle 71 is started (step S52). Then, in step S53, the stepping of the protrusion PS2 by the nozzle guard 72 which descends integrally with the slit nozzle 71 is monitored, and the slit nozzle 71 is returned to step S53 while it does not reach the coating position (NO in step S54), and the descent of the slit nozzle 71 is continued.

When the collision of the nozzle guard 72 with the protrusion PS2 during such lowering of the slit nozzle 71 is detected by the stress detection sensor 701, a signal associated therewith is sent to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (YES in step S53), and forcibly stops the coating process at that point in time (step S6). That is, the discharge of the coating liquid from the slit nozzle 71 and the floating conveyance of the substrate S are stopped. Further, as an alarm, a warning screen indicating that the protrusion PS2 is detected in the vicinity of the application position is displayed on the display portion 94 of the control unit 9 (step S7).

On the other hand, at the point in time when it is determined to be "yes" in step S54, the slit nozzle 71 is positioned at the coating position. Then, during the period before being positioned, a signal indicating a collision is not input from the stress detection sensor 701 (no in step S53), and it is confirmed that the stepping of the protrusion PS2 does not occur. That is, the slit nozzle 71 is properly positioned at the coating position without generating stepping of the nozzle guard 72 against the protrusion PS 2. Therefore, the coating operation is started (step S8). That is, the coating liquid discharged from the discharge port 711 of the slit nozzle 71 adheres to the surface Sf of the substrate S. The chuck mechanism 51 carries the substrate S at a constant speed so as to pass through the coating region sandwiched between the nozzle guard 72 and the slit nozzle 71 and the platen 33, thereby performing a coating operation in which the slit nozzle 71 applies the coating liquid onto the surface Sf of the substrate S, and forming a coating film of a constant thickness obtained from the coating liquid on the surface Sf of the substrate S. In addition, during the coating operation performed in this way, when the rotation detection sensor detects the protrusion PS1, the coating process is forcibly stopped as in the case when the stress detection sensor 701 detects the protrusion PS 2. Then, the discharge of the coating liquid from the slit nozzle 71 is stopped, the floating conveyance of the substrate S is stopped, and a warning screen is displayed.

The coating operation is continued until the substrate S is conveyed to the end position where the coating should be ended (step S9). When the substrate S reaches the end position (yes in step S8), the slit nozzle 71 is separated from the application position and returned to the maintenance position, and the preliminary discharge process is performed again. Further, at the point in time when the chuck mechanism 51 reaches the conveyance end position on the output transfer unit 4 at the downstream end of the substrate S, the movement of the chuck mechanism 51 is stopped, and the suction holding is released. Then, the substrate S is carried out in the (+ X) direction via the downstream floating stage 3C and the output transfer unit 4 (step S10), and finally sent out to the downstream unit. If there is a substrate to be processed next (yes in step S11), the same processing as described above is repeated, and if not (no in step S11), the processing is terminated.

As described above, according to the first embodiment, by providing the nozzle guard 72, not only the protrusion PS1 but also the protrusion PS2 existing at or near the coating position Pc can be reliably detected at the start time point of the coating action. Therefore, the protrusion PS2 is prevented from being stepped in advance, and the coating liquid (processing liquid) is prevented from being applied to the substrate S. That is, the coating process can be forcibly stopped at the detection timing of the protrusion PS2, and it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the protrusion PS2 because the coating operation is continued in a state where the protrusion PS2 is stepped on by dragging the nozzle guard 72.

Further, according to the first embodiment, both the protrusion PS2 existing at the descending destination of the nozzle guard 72 and the protrusion PS1 existing on the (-X) direction side of the descending destination can be reliably detected, and adverse effects of the protrusion on the coating process can be prevented in advance with higher accuracy than in the related art.

In the first embodiment, the suction/travel control mechanism 52 corresponds to an example of the "moving mechanism" of the present invention. The "(-X) direction side corresponds to an example of the" front side of the slit nozzle "of the present invention. The nozzle driving mechanism 8 corresponds to an example of the "elevating mechanism" of the present invention. The stress detection sensor 701 corresponds to an example of a "collision detection unit". Step S52 and step S53 correspond to an example of the "descent process" and the "collision detection process" of the present invention, respectively.

In the first embodiment, the stress acting on the nozzle guard 72 is directly detected by the stress detection sensor 701, but the mounting position of the stress detection sensor 701 is not limited thereto. That is, the stress generated when the nozzle guard 72 steps on the protrusion PS2 propagates toward the guard support 73 or the slit nozzle 71. Therefore, the stress detection sensor 701 may be mounted to the guard support 73 or the slit nozzle 71 to indirectly detect the stress.

< Second embodiment >

The nozzle guard 72, the guard support 73, and the slit nozzle 71 integrally vibrate in the up-down direction Z by the collision when the nozzle guard 72 steps on the protrusion PS 2. Accordingly, a vibration sensor that detects vertical vibrations may be attached to any one of the nozzle guard 72, the guard support 73, and the slit nozzle 71 instead of the stress detection sensor 701.

Fig. 7 is a partially enlarged view of a second embodiment of the substrate processing apparatus of the present invention. The second embodiment is greatly different from the first embodiment in that a vibration sensor 702 is mounted to the slit nozzle 71 instead of the stress detection sensor 701. The other structure is the same as the first embodiment.

In the second embodiment, as in the first embodiment, the movement and positioning of the slit nozzle 71 from the preliminary discharge position to the application position Pc are performed in two stages. That is, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the slit nozzle 71 descends integrally with the nozzle guard 72 (step S52). During the descent, it is assumed that if the nozzle guard 72 collides with the projection PS2, the slit nozzle 71 is thereby vibrated in the up-down direction Z. The vibration sensor 702 detects the vibration and sends a signal associated therewith to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (yes in step S53), and forcibly stops the coating process at the point in time (step S6).

As described above, in the second embodiment, the vibration sensor 702 corresponds to an example of the "collision detecting portion" of the present invention, and functions and effects similar to those of the first embodiment are obtained. That is, by detecting the vertical vibration of the vibration sensor 702, the protrusion PS2 is prevented from being stepped on in advance, and thus the coating liquid (processing liquid) is prevented from being applied to the substrate S. As a result, it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the projection PS2 because the coating operation is continued in a state where the projection PS2 stepped on by the nozzle guard 72 is dragged.

In the second embodiment, the vibration sensor 702 is provided instead of the stress detection sensor 701, but both sensors may be used in combination.

< Third embodiment >

Fig. 8 is a partially enlarged view of a third embodiment of the substrate processing apparatus of the present invention. The third embodiment is greatly different from the first embodiment in that it is configured to detect up-and-down movement of the nozzle guard 72 accompanying the impact instead of detecting the impact by the stress detection sensor 701. That is, in the third embodiment, the nozzle guard 72 is slidably attached to the guard support 73 along the long hole 721 extending in the up-down direction Z. In addition, a position sensor 703 that detects the displacement amount of the nozzle guard 72 in the up-down direction Z is provided. The other structure is the same as the first embodiment.

In the third embodiment, as in the first embodiment, the movement and positioning of the slit nozzle 71 from the preliminary discharge position to the application position Pc are performed in two stages. That is, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the slit nozzle 71 descends integrally with the nozzle guard 72 (step S52). During the descent, it is assumed that the nozzle guard 72 collides with the protrusion PS2 to limit the descent motion. Accordingly, the relative position of the nozzle guard 72 with respect to the slit nozzle 71 in the up-down direction Z is displaced, and a signal corresponding to the displacement amount is sent from the position sensor 703 to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (yes in step S53), and forcibly stops the coating process at the point in time (step S6).

As described above, in the third embodiment, the position sensor 703 corresponds to an example of the "collision detecting unit" of the present invention, and functions and effects similar to those of the first embodiment are obtained. That is, by detecting the displacement of the relative position of the nozzle guard 72 with respect to the slit nozzle 71 by the position sensor 703, it is possible to prevent the coating liquid (processing liquid) from being applied to the substrate S by stepping on the protrusion PS2 in advance. As a result, it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the projection PS2 because the coating operation is continued in a state where the projection PS2 stepped on by the nozzle guard 72 is dragged.

< Fourth embodiment >, a third embodiment

Fig. 9A and 9B are partial enlarged views of a fourth embodiment of the substrate processing apparatus according to the present invention. The fourth embodiment is greatly different from the first embodiment in that the nozzle guard 72 is mounted to the guard support 73 in a state of being inclined in advance, and in place of the stress detection sensor 701, there is provided a rotation encoder or the like detecting sensor 704 that detects the rotation amount of the nozzle guard 72. The other structure is the same as the first embodiment.

In the fourth embodiment, the front end of the nozzle guard 72 is located on the (+ X) direction side of the support shaft 74 (shaft fulcrum), and in the inclined posture inclined by the angle θa, the rear end portion of the nozzle guard 72, that is, the portion above the support shaft 74 is biased to the (+ Z) direction side by the spring 75, and the rotation to the (+ X) direction side is restricted by the stopper 76. Thus, as shown in fig. 9A, when the slit nozzle 71 is located at the position above the coating position Pc, the nozzle guard 72 maintains the inclined posture inclined by the angle θa. On the other hand, as shown in fig. 9B, when the nozzle guard 72 descends together with the slit nozzle 71, the nozzle guard 72 swings about the support shaft 74 as a swing center in accordance with contact between the tip end thereof and the protrusion PS2, and as a result, swings counterclockwise on the paper surface of fig. 9B, and the inclination angle expands to the angle θb. The angle detection sensor 704 is capable of detecting the angle change and transmitting a signal corresponding thereto to the control unit 9.

In the fourth embodiment, as in the first embodiment, the movement and positioning of the slit nozzle 71 from the preliminary discharge position to the application position Pc are performed in two stages. That is, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the slit nozzle 71 descends integrally with the nozzle guard 72 (step S52). During the descent, the nozzle guard 72 maintains the inclined posture of the angle θa. Here, when the descent of the slit nozzle 71 is further progressed after the collision of the nozzle guard 72 with the protrusion PS2, the nozzle guard 72 swings by the amount by which it is progressed, and the inclination angle of the nozzle guard 72 becomes the angle θb from the angle θa. The angle detection sensor 704 detects the angular displacement and sends a signal associated therewith to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (yes in step S53), and forcibly stops the coating process at the point in time (step S6).

In this way, in the fourth embodiment, the angle detection sensor 704 corresponds to an example of the "collision detection unit" of the present invention, and functions and effects similar to those of the first embodiment are obtained. That is, by detecting the swing of the nozzle guard 72 by the angle detection sensor 704, the protrusion PS2 is prevented from being stepped on in advance, and the application of the coating liquid (processing liquid) to the substrate S is prevented from being adversely affected. As a result, it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the projection PS2 because the coating operation is continued in a state where the projection PS2 stepped on by the nozzle guard 72 is dragged.

< Fifth embodiment >, a third embodiment

In the floating coating apparatus 1, the substrate S is conveyed in a state of being lifted from the stage surface 33 by a predetermined amount, and the processing liquid is supplied to the surface Sf of the substrate S to perform coating. Also, when the nozzle guard 72 steps on the protrusion PS2, the amount of floating in the coating area decreases. Therefore, the collision of the nozzle guard 72 with the protrusion PS2 can also be detected based on the change in the floating amount (fifth embodiment).

Fig. 10 is a partially enlarged view of a fifth embodiment of the substrate processing apparatus of the present invention. The fifth embodiment is greatly different from the first embodiment in that a floating amount measuring section 705 that measures the floating amount of the substrate S from the stage surface 33 in the coating region is provided instead of the stress detection sensor 701. The other structure is the same as the first embodiment.

In the fifth embodiment, the floating amount measuring unit 705 includes a displacement meter 705a attached to the slit nozzle 71 and measuring a distance to the front surface Sf of the substrate S, and a displacement meter 705B fixedly disposed below the center floating platform 3B and measuring a distance to the rear surface Sb of the substrate S. Signals associated with the distances measured with these displacement meters 705a, 705b are sent to the control unit 9.

In the fifth embodiment, as in the first embodiment, the movement and positioning of the slit nozzle 71 from the preliminary discharge position to the application position Pc are performed in two stages. That is, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the slit nozzle 71 descends integrally with the nozzle guard 72 (step S52). In the course of lowering of the slit nozzle 71, when the nozzle guard 72 collides with the projection PS2 and steps on, as shown in fig. 10, the amount of floating of the substrate S in a part of the coating area, more specifically, in the vicinity of the tip of the nozzle guard 72, is reduced, and a signal reflecting the measurement results obtained by the displacement meters 705a, 705b is sent to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (yes in step S53), and forcibly stops the coating process at the point in time (step S6).

As described above, in the fifth embodiment, the floating amount measuring unit 705 corresponds to an example of the "collision detecting unit" of the present invention, and functions and effects similar to those of the first embodiment are obtained. That is, by detecting the change in the floating amount by the floating amount measuring section 705, it is possible to prevent the protrusion PS2 from being stepped on in advance, thereby adversely affecting the application of the coating liquid (processing liquid) to the substrate S. As a result, it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the projection PS2 because the coating operation is continued in a state where the projection PS2 stepped on by the nozzle guard 72 is dragged.

In the fifth embodiment, the floating amount measuring unit 705 is composed of two types of displacement meters 705a for measuring the distance from the upper side and 705b for measuring the distance from the lower side, but other distance measurement, for example, a displacement meter for measuring the distance from the slit nozzle 71 to the land 33 may be further added. Conversely, the floating amount measuring unit 705 may be constituted by only the displacement meter 705 b.

In the fifth embodiment, the displacement meters 705a and 705b detect the change in the floating amount, but the change in the floating amount may be detected based on another method, for example, capturing an image of the coating region from the Y direction.

< Sixth embodiment >

In the floating coating apparatus 1, the substrate S is floated by a pressure gas layer formed on the platen surface 33 by a gas flow passing through gas holes (the discharge holes 34a and the suction holes 34 b) provided on the platen surface 33. Therefore, when the nozzle guard 72 steps on the protrusion PS2, the thickness of the pressure gas layer in the coating region decreases, and turbulence occurs in the gas flow, reflecting this, the pressure measured by the pressure gauge 353d, 354b changes. Therefore, the collision of the nozzle guard 72 with the protrusion PS2 can also be detected based on the output changes of the pressure gauge 353d, 354b (sixth embodiment).

Fig. 11 is a partially enlarged view of a sixth embodiment of the substrate processing apparatus of the present invention. The sixth embodiment is greatly different from the first embodiment in that signals associated with the pressures measured by the pressure gauges 353d, 354b are sent to the control unit 9 instead of the stress detection sensor 701. The other structure is the same as the first embodiment.

In the sixth embodiment, as in the first embodiment, the movement and positioning of the slit nozzle 71 from the preliminary discharge position to the application position Pc are performed in two stages. That is, the slit nozzle 71 is moved to a position above the coating position Pc by the nozzle driving mechanism 8 (step S51). Immediately thereafter, the slit nozzle 71 descends integrally with the nozzle guard 72 (step S52). In the process of lowering the slit nozzle 71, when the nozzle guard 72 collides with the projection PS2 and steps on, as shown in fig. 11, the substrate S is pushed downward in a part of the coating region, more specifically, in the vicinity of the tip of the nozzle guard 72, and the amount of floating changes. At this time, turbulence is generated in the gas flow constituting the pressure gas layer. Accordingly, a signal reflecting the measurement results obtained by the manometer 353d and the manometer 354b is transmitted to the control unit 9. The arithmetic unit 91 of the control unit 9 that received the signal determines that the stepping of the nozzle guard 72 on the protrusion PS2 has occurred (yes in step S53), and forcibly stops the coating process at the point in time (step S6).

As described above, in the sixth embodiment, the pressure gauge 353d and the pressure gauge 354b correspond to examples of the "collision detecting portion" and the "pressure measuring portion" of the present invention, and the same operational effects as those of the first embodiment are obtained. That is, by detecting the pressure change by the pressure gauge 353d and the pressure gauge 354b, the protrusion PS2 is prevented from being stepped on in advance, and adverse effects on the application of the coating liquid (processing liquid) to the substrate S can be prevented. As a result, it is possible to reliably prevent the coating liquid from being blocked from being applied to the substrate S by the projection PS2 because the coating operation is continued in a state where the projection PS2 stepped on by the nozzle guard 72 is dragged.

In the sixth embodiment, the pressure gauge 353d of the ejection system and the pressure gauge 354b of the suction system are used as the "collision detecting portion" of the present invention, but only one of them may be used as the "collision detecting portion".

The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the gist thereof. For example, in the first to fourth embodiments, the present invention is applied to a so-called floating substrate processing apparatus, but the application object of the present invention is not limited thereto, and the present invention may be applied to a substrate processing apparatus in which, for example, the slit nozzle is moved relative to the substrate and the processing liquid is discharged from the slit nozzle, as described in patent document 1.

In the above embodiment, the nozzle guard 72 is made of a long non-transparent material having a flexibility and a length longer than the Y-direction dimension of the substrate S, but a member in which a plurality of short members are arranged in the Y-direction may be used as described in patent document 1. In this case, it is desirable to provide a stress detection sensor 701, a position sensor 703, an angle detection sensor 704, and the like for each member.

[ Industrial applicability ]

The present invention can be applied to all substrate processing techniques in which a processing liquid is supplied from a slit nozzle to a substrate and applied.

Claims (11)

1. A substrate processing apparatus that applies a processing liquid onto a surface of a substrate, the substrate processing apparatus comprising:

a slit nozzle having a slit-shaped discharge port;

a moving mechanism that relatively moves the slit nozzle with respect to the substrate;

A nozzle guard that is disposed on a front side of the slit nozzle in a nozzle traveling direction in which the slit nozzle travels relatively to the substrate by the moving mechanism, and moves integrally with the slit nozzle;

a lifting mechanism for lifting and lowering the slit nozzle and the nozzle guard integrally; and

And a collision detecting unit configured to detect that a tip of the nozzle guard lowered by the elevating mechanism protrudes upward on the front surface side of the substrate and collides with and steps on a protrusion that blocks the application of the processing liquid when the slit nozzle is lowered to a position where the slit nozzle starts to apply the processing liquid, the position being located at a position where the slit nozzle starts to apply the processing liquid, in combination with the nozzle guard, before the slit nozzle starts to apply the processing liquid.

2. The substrate processing apparatus according to claim 1, wherein,

The collision detecting portion detects collision of the nozzle guard with the protrusion based on stress or vibration in an up-down direction applied to at least one of the nozzle guard and the slit nozzle when the front end of the nozzle guard collides with the protrusion.

3. The substrate processing apparatus according to claim 2, wherein,

The collision detecting section has a load cell that is attached to at least one of the nozzle guard and the slit nozzle and detects a stress applied upward.

4. The substrate processing apparatus according to claim 2, wherein,

The collision detecting portion has a vibration sensor that is mounted to at least one of the nozzle guard and the slit nozzle and detects vibration in the up-down direction.

5. The substrate processing apparatus of claim 1, further comprising a guard support,

The shield support portion supports a rear end portion of the nozzle shield with respect to the slit nozzle,

The nozzle guard is displaceably supported by the guard support portion in accordance with the front end of the nozzle guard colliding with the projection in the middle of the descent integrally with the slit nozzle,

The collision detecting portion detects a collision of the nozzle guard with the protrusion based on an upward displacement of the nozzle guard.

6. The substrate processing apparatus according to claim 5, wherein,

The nozzle guard is supported by the guard support portion so as to be slidable in the up-down direction,

The collision detecting section has a position sensor that detects upward displacement of the nozzle guard in accordance with collision of the front end of the nozzle guard with the projection.

7. The substrate processing apparatus according to claim 5, wherein,

The nozzle guard is supported by the guard support portion so as to swing freely about an axis fulcrum, the rear end portion of which is rotatably supported by the guard support portion,

The collision detecting portion has an angle detecting sensor that detects an angle at which the nozzle guard swings about the shaft fulcrum in accordance with the front end of the nozzle guard colliding with the protrusion.

8. A substrate processing apparatus that applies a processing liquid onto a surface of a substrate, the substrate processing apparatus comprising:

a slit nozzle having a slit-shaped discharge port;

a moving mechanism that relatively moves the slit nozzle with respect to the substrate;

A nozzle guard that is disposed on a front side of the slit nozzle in a nozzle traveling direction in which the slit nozzle travels relatively to the substrate by the moving mechanism, and moves integrally with the slit nozzle;

a lifting mechanism for lifting and lowering the slit nozzle and the nozzle guard integrally;

A collision detecting unit configured to detect that a tip of the nozzle guard lowered by the elevating mechanism protrudes upward on a surface side of the substrate and collides with a protrusion that blocks application of the processing liquid when the slit nozzle is lowered to a position where the slit nozzle starts to apply the processing liquid, the position being located at a position where the slit nozzle starts to apply the processing liquid, before the slit nozzle starts to apply the processing liquid; and

A floating portion that floats the substrate by a pressure gas layer formed on a stage surface by a gas flow passing through a gas hole provided on the stage surface,

The slit nozzle is arranged above the platform surface,

The moving mechanism moves the substrate lifted from the platen surface by the lifting portion so as to pass through a coating region sandwiched between the slit nozzle and the nozzle guard and the platen surface,

The collision detecting section detects a collision of the nozzle guard with the protrusion based on a change in the floating amount of the substrate in the coating region.

9. The substrate processing apparatus according to claim 8, wherein,

The collision detecting section has a floating amount measuring section that measures the floating amount, and detects a change in the floating amount measured by the floating amount measuring section in accordance with the collision of the front end of the nozzle guard with the protrusion.

10. The substrate processing apparatus according to claim 8, wherein,

The collision detecting section has a pressure measuring section that measures a pressure of the gas flow, and detects a change in the pressure measured by the pressure measuring section corresponding to a change in the floating amount accompanying a collision of the tip of the nozzle guard with the protrusion.

11. A substrate processing method of applying a processing liquid to a surface of a substrate by relatively moving a slit nozzle with respect to the substrate while discharging the processing liquid from a discharge port of the slit nozzle in a state where the discharge port is close to the surface of the substrate, the substrate processing method comprising:

A lowering step of lowering the slit nozzle and a nozzle guard disposed on a front side of the slit nozzle in a nozzle traveling direction in which the slit nozzle travels relative to the substrate, toward a position where the slit nozzle starts to apply the processing liquid, before the slit nozzle starts to apply the processing liquid, so that the discharge port approaches a surface of the substrate; and

And a collision detection step of detecting whether or not the tip of the nozzle guard protrudes upward on the front surface side of the substrate in the descent step, collides with a protrusion that blocks the application of the processing liquid from above, and steps on.