Photoresist smearing device for coating

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a photoresist smearing device for coating, which comprises a box body; the conveying assembly is used for conveying a substrate to be coated to a coating station and is arranged on the box body; the coating and cleaning integrated switching mechanism is arranged above the box body; the coating and cleaning integrated switching mechanism comprises a rotary switching assembly used for driving the two slit coating die heads to be switched between a coating station and a cleaning station; and the glue supply and waste discharge assembly is used for supplying glue to the coating position die head and extracting residual glue from the cleaning position die head. According to the device, through cooperation of the annular variable-diameter guide groove and the first elastic telescopic rod, automatic compensation of rotating avoiding and accurate positioning is achieved, the die head automatically avoids and resets during switching, and it is ensured that the distance between the nozzle and a base plate or a cleaning piece is constant; due to the design of the convex section, the working position is accurately butted with the cleaning position, and the thickness uniformity and the cleaning effect of a coating film are effectively guaranteed.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a photoresist coating apparatus. Background Technology

[0002] In semiconductor manufacturing, flat panel displays, and advanced packaging processes, uniform photoresist coating is a crucial step in determining the quality of pattern transfer. Slit coating technology, with its high material utilization, excellent film thickness consistency, and adaptability to large-area substrates, has become the mainstream solution. This process uses precision slit nozzles to continuously extrude photoresist, forming a nanoscale thin film on a high-speed moving substrate.

[0003] However, photoresist is susceptible to particulate contamination, solvent evaporation, or temperature fluctuations, which can easily lead to localized blockages at the nozzle outlet, causing coating interruptions, uneven film thickness, or even complete waste, severely restricting yield and production efficiency. Existing solutions have significant limitations: first, relying on pre-coating filtration and environmental control cannot completely eliminate blockages during long-term continuous production; second, blockages require manual disassembly, cleaning, or replacement, which not only reduces overall equipment efficiency but also introduces human error or damages precision structures, increasing maintenance costs. Even with online pressure monitoring in some equipment, alarms are only triggered, not automatic recovery. In recent years, while some research has attempted to introduce redundant main / backup multi-nozzle designs to address blockages by switching channels, these solutions have significant drawbacks: first, the switching mechanism is complex and space-consuming, making it difficult to integrate into compact modules; second, the original blocked nozzle is not cleaned after switching, posing a risk upon reactivation; and third, the lack of precise identification of blockage locations necessitates full-channel flushing, resulting in waste of expensive photoresist and low cleaning efficiency. Most importantly, existing technologies cannot achieve a closed-loop operation of "blockage detection - channel switching - in-situ cleaning - status reset" without stopping the machine or interrupting the coating process.

[0004] Therefore, developing a coating device that can automatically identify and clear nozzle blockages without interrupting production has become a pressing technical challenge in this field. Summary of the Invention

[0005] In order to overcome the shortcomings of existing technologies that make it difficult to achieve fully automatic closed-loop functions such as blockage detection, channel switching, in-situ cleaning, and state reset without stopping the machine, this invention provides a photoresist coating device.

[0006] A photoresist coating apparatus includes: a housing; a conveying assembly for transporting a substrate to be coated to a coating station, which is disposed on the housing; and an integrated coating and cleaning switching mechanism disposed above the housing. The integrated coating and cleaning switching mechanism includes: a rotary switching assembly for driving two slit coating dies to switch between a coating station and a cleaning station; a photoresist supply and waste removal assembly for supplying photoresist to the slit coating die located at the coating station and for suctioning residual photoresist from the slit coating die located at the cleaning station; a cleaning assembly for performing air jet cleaning on the slit coating die switched to the cleaning station; and a control system, which controls the rotary switching assembly to operate according to a pressure detection signal, and sequentially starts the waste removal and cleaning operations after switching, thereby achieving automatic nozzle clogging without stopping the machine.

[0007] Furthermore, the rotary switching assembly includes: a fixed frame fixed to the top of the housing, with guide supports symmetrically arranged on the front and rear side walls of the fixed frame; a dual-position switching drive motor mounted on the rear guide support; a blind tube rotating body coaxially fixed to the output shaft of the dual-position switching drive motor, the blind tube rotating body being a cylindrical shape with a closed rear end, with branch flow channels symmetrically arranged on its upper and lower sides communicating with its inner cavity; and a dual-channel static manifold fixed to the middle of the front guide support, the rear end of the dual-channel static manifold extending into the cavity of the blind tube rotating body to form a rotary sealing coupling structure, and its outer diameter precisely matching the inner diameter of the blind tube rotating body, allowing the blind tube rotating body to rotate freely around it.

[0008] Furthermore, the glue supply and waste discharge assembly includes a positive pressure glue supply channel and a negative pressure waste discharge channel arranged in parallel within the dual-channel static manifold; the positive pressure glue supply channel is used to connect to the glue supply system, and the outlet end of the negative pressure waste discharge channel is connected to an independent waste liquid recovery unit, which is physically isolated from the glue supply system; there are two branch flow channels, which are respectively connected to the upper and lower slit coating dies; when the blind tube rotator rotates to the first working position, the lower branch flow channel is connected to the positive pressure glue supply channel, and the upper branch flow channel is connected to the negative pressure waste discharge channel; when the blind tube rotator rotates 180° to the second working position, the upper and lower connections are reversed.

[0009] Furthermore, each slit coating die is mounted on the corresponding branch channel pipe and can slide along the axial direction of the branch channel pipe; each slit coating die is fixedly connected to a first elastic telescopic rod symmetrically distributed along the branch channel pipe on the side near the blind tube rotating body, and the telescopic end of each first elastic telescopic rod is fixedly connected to the blind tube rotating body to buffer radial displacement during rotation and assist in resetting.

[0010] Furthermore, each slot coating die head is equipped with positioning protrusions on both the front and rear sides, and each guide support has an annular variable diameter guide groove, with each positioning protrusion correspondingly embedded in the annular variable diameter guide groove. The annular variable diameter guide groove has radially outward protrusions on both the top and bottom sides, which are used to extend the slot coating die head outward during the coating and cleaning stations, maintaining a precise distance from the substrate and the cleaning components. Each annular variable diameter guide groove has a one-way anti-reverse right-angle surface at the right corner of the top outward protrusion, which is used to force the slot coating die head to rotate only counterclockwise, ensuring the certainty of the switching sequence.

[0011] Furthermore, the cleaning assembly is a pneumatic self-locking online cleaning module located on top of the fixed frame, comprising: four second elastic telescopic rods symmetrically fixed to the top wall of the fixed frame; flexible docking cleaning nozzles fixed to the telescopic ends of the four second elastic telescopic rods, wherein the second elastic telescopic rods integrate pre-tightening return springs to enable the flexible docking cleaning nozzles to float axially; a high-pressure air inlet is provided on the front wall of the flexible docking cleaning nozzles for connecting to a high-pressure air source; and a contoured sealing docking groove is provided at the bottom to match the slit nozzle of the slit coating die head.

[0012] Furthermore, the rear wall of the flexible docking cleaning nozzle is evenly distributed with independent exhaust micro-holes along the circumference. These independent exhaust micro-holes are connected to an external independent negative pressure dust collection pipeline to discharge waste gas containing impurities and solid particles generated during blowing. This sewage discharge path is independent of the negative pressure waste discharge channel.

[0013] Furthermore, it also includes a follow-up vent valve assembly for controlling the opening and closing of the high-pressure air path; the follow-up vent valve assembly includes: a three-way manifold fixed to the front wall of the fixed frame, the rear end of which is tightly fitted with the high-pressure air inlet; a push-type reversing valve core vertically slidably connected to the three-way manifold, which is connected to the top wall of the three-way manifold by a linear return spring; a vent hole is opened longitudinally in the push-type reversing valve core; and a cam guide block fixed to the front side of each slit coating die head. Initially, the vent hole is aligned with the main channel of the three-way manifold, the air path is open, and the linear return spring is in a compressed state. When the slit coating die head is in the cleaning station and fully reset, the cam guide block abuts against the push-type reversing valve core, keeping it in a high position. The linear return spring is compressed, and the vent hole is aligned with the main channel of the three-way manifold, thus opening the air path. When the slit coating die head leaves the cleaning station, the cam guide block disengages, the compressed linear return spring resets, causing the push-type reversing valve core to move downwards and reset, thus cutting off the air path.

[0014] Furthermore, each slit coating die head includes a left die body and a right die body that are connected to each other. A flow channel cavity for accommodating photoresist and a coating slit communicating with the outside are formed between the left die body and the right die body; the left die body and the right die body are fixedly connected by locking bolts.

[0015] Beneficial effects: Through the coordinated operation of the rotary switching component, glue supply and waste discharge component, and cleaning component, this device automatically starts the dual-position switching drive motor when nozzle blockage is detected, driving the blind tube rotator to rotate 180° and switching the spare die head to the working position, so that the coating operation can continue without interruption; at the same time, the blocked die head is rotated to the cleaning position to complete the residual glue suction and air jet cleaning in sequence; the entire process realizes a fully automatic closed loop of "blockage detection - automatic switching - step cleaning - status reset", without the need for machine shutdown and manual intervention, which significantly improves the overall efficiency of the equipment and the product yield.

[0016] This device features an annular variable-diameter guide groove within the guide support component, which, in conjunction with the elastic compensation of the first elastic telescopic rod, achieves an automatic compensation function of "rotation avoidance - precise positioning." During the switching process, the die head slides inward along the branch flow channel to avoid interference, and then resets outward after reaching its position, ensuring that the perpendicularity and spacing between the nozzle and the substrate or cleaning component remain constant. The outward convex section design of the annular variable-diameter guide groove ensures that the working die head and the substrate maintain the optimal coating spacing, and the cleaning die head and the cleaning nozzle are precisely aligned, effectively guaranteeing the uniformity of the coating thickness and the cleaning effect.

[0017] This device adopts a step-by-step cleaning strategy of "draining first, then purging, and independent waste discharge": After the blockage mold head is moved to the cleaning position, the residual liquid photoresist inside is first drawn into the independent waste liquid recovery unit through the negative pressure waste discharge channel to realize the recovery of liquid phase residual photoresist; then, the solidified particles are purged by high-pressure air jet through the flexible docking cleaning nozzle. The waste gas and solid particles generated by purging are discharged independently through the external negative pressure dust suction pipeline through the independent exhaust micro-holes on the rear wall of the cleaning nozzle. This waste discharge path is completely independent of the negative pressure waste discharge channel, which completely avoids solid phase contaminants from mixing into the liquid phase recovery system or flowing back to the glue supply circuit, effectively ensuring the cleanliness and long-term stability of the system. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0019] Figure 2 This is a three-dimensional structural diagram of the components of the present invention, including the fixed frame, the slit coating die head, and the flexible docking cleaning nozzle.

[0020] Figure 3 This is a three-dimensional structural diagram of the components of the present invention, including the dual-channel static manifold, the blind tube rotating body, and the guide support.

[0021] Figure 4 This is a three-dimensional structural diagram of the guide support component of the present invention.

[0022] Figure 5 This is a three-dimensional structural diagram of the components of the present invention, including the dual-channel static manifold, the slit coating die, and the first elastic telescopic rod.

[0023] Figure 6 This is a three-dimensional structural diagram of the components of the present invention, including the second elastic telescopic rod, the three-way manifold, and the flexible docking cleaning nozzle.

[0024] Figure 7 This is a three-dimensional structural diagram of the flexible docking cleaning nozzle of the present invention.

[0025] Figure 8 This is a three-dimensional structural diagram of the components of the present invention, including the three-way manifold, the flexible docking cleaning nozzle, and the cam guide block.

[0026] Figure 9 This is a three-dimensional structural diagram of the linear reset spring, push-type reversing valve core, and three-way manifold of the present invention.

[0027] Meaning of reference numerals in the diagram: 101-Box body, 102-Conveying assembly, 103-Fixed frame, 104-Guide support, 1041-Annular variable diameter guide groove, 105-Dual-channel static manifold, 106-Slot coating die head, 1061-Flow channel cavity, 1062-Coating slot, 107-Locking bolt, 108-Positive pressure glue supply channel, 109-Negative pressure waste discharge channel, 110-First elastic telescopic rod, 111-Dual-position switching Drive motor, 112-blind tube rotating body, 113-branch flow channel pipe, 200-pneumatic self-locking online cleaning module, 201-second elastic telescopic rod, 202-flexible docking cleaning nozzle, 203-contour sealing docking groove, 204-high pressure air inlet, 300-follow-up vent valve assembly, 301-cam guide block, 302-three-way manifold, 303-push-type reversing valve core, 304-vent hole, 305-linear return spring. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1: A photoresist coating apparatus, such as... Figures 1-5 As shown, the system includes a housing 101 that serves as the main support. A conveying assembly 102 is mounted on the housing 101, which precisely transports the substrate to be coated to a position directly below the coating station. The coating process is triggered once the substrate is in place, thanks to a control system. A fixing frame 103 is fixedly attached to the upper part of the housing 101, and guide supports 104 are symmetrically arranged on its front and rear side walls.

[0030] A dual-position switching drive motor 111 is mounted on the rear guide support 104. Its output shaft passes through the middle of the guide support 104 and is coaxially fixed to a blind tube rotating body 112 via a coupling, serving as the core execution component for mold head switching. The blind tube rotating body 112 is a cylindrical shape with a closed rear end, and branch flow channels 113 are symmetrically opened on its upper and lower sides, communicating with its inner cavity.

[0031] A dual-channel static manifold 105 is fixedly connected to the middle of the front guide support 104, with its rear end extending into the cavity of the blind tube rotating body 112, forming a rotary sealing coupling structure. The outer diameter of the dual-channel static manifold 105 is precisely matched with the inner diameter of the blind tube rotating body 112, allowing the blind tube rotating body 112 to rotate freely around it. A positive pressure glue supply channel 108 and a negative pressure waste discharge channel 109 are arranged in parallel inside the dual-channel static manifold 105.

[0032] The positive pressure photoresist supply channel 108 is used for the forward transport of photoresist during normal coating operations and is connected to the output end of the photoresist supply system. The negative pressure waste discharge channel 109 is dedicated to the negative pressure suction of residual photoresist after die head switching. Its outlet end is connected to an independent waste liquid recovery unit, which is physically isolated from the photoresist supply system to ensure that the suctioned residual photoresist does not mix with the fresh photoresist.

[0033] Each branch channel pipe 113 is equipped with a slit coating die 106. The lower slit coating die 106 is in the working position, and the upper slit coating die 106 is in the standby and cleaning position. Each slit coating die 106 has a first elastic telescopic rod 110 symmetrically distributed along the branch channel pipe 113 fixedly connected to the side near the blind tube rotating body 112. The telescopic end of the rod is fixedly connected to the blind tube rotating body 112 to buffer radial displacement during rotation.

[0034] The ends of each branch flow channel 113 extend into the internal flow channel of the corresponding slit coating die 106, and the slit coating die 106 can slide along the axial direction of the branch flow channel 113.

[0035] Each slot coating die 106 has positioning protrusions on both its front and rear sides, and each guide support 104 has an annular variable diameter guide groove 1041, into which the positioning protrusions are embedded. The annular variable diameter guide groove 1041 has radially outward protrusions on its top and bottom sides. These protrusions serve two functions: first, in the working position, they extend the slot coating die 106 outwards to ensure the lower slot coating die 106 maintains the optimal coating distance with the substrate; second, in the cleaning position, they extend the slot coating die 106 outwards to ensure precise alignment between the upper slot coating die 106 and the cleaning component. A one-way anti-reverse right-angle surface is provided at the right corner of the top protrusion, forcibly limiting the slot coating die 106 to only rotate counterclockwise, ensuring the certainty of the switching sequence.

[0036] Initially, both the upper and lower slot coating dies 106 are located on the outer convex section of the annular variable diameter guide groove 1041, ensuring that the slot coating die 106 in the lower working position maintains the optimal coating distance with the substrate. When the dual-position switching drive motor 111 drives the blind tube rotating body 112 to rotate 180° counterclockwise, the positioning protrusion slides from the outer convex section into the contraction section, forcing the two slot coating dies 106 to move inward. At this time, the slot coating dies 106 slide inward along the branch flow channel 113, and the first elastic telescopic rod 110 adaptively contracts to automatically compensate for the radial displacement during the rotation process, avoiding mechanical interference with the fixed frame 103.

[0037] After the swap is completed, the protruding column re-enters the outer protruding section, and the slit coating die head 106 resets outward along the branch flow channel 113 under the constraint of the annular variable diameter guide groove 1041. The first elastic telescopic rod 110 extends synchronously to ensure that the perpendicularity and spacing between the nozzle of the slit coating die head 106 and the substrate or cleaning part remain constant, realizing the automatic compensation function of "rotation avoidance - precise positioning".

[0038] The conveying assembly 102 consists of a conveyor belt, two conveyor rollers, and a conveyor motor. The two conveyor rollers are rotatably connected to the left and right sides of the housing 101, respectively, and the conveyor belt is wound around the two conveyor rollers. The housing 101 is equipped with a conveyor motor, the output shaft of which is fixedly connected to the adjacent conveyor roller via a coupling, for the purpose of continuous and stable conveying of the substrate.

[0039] Each slot coating die 106 includes a left die body and a right die body that are connected to each other. A flow channel cavity 1061 for containing photoresist and a coating slot 1062 communicating with the outside are formed between the left and right die bodies. The left and right die bodies are fixedly connected by eight locking bolts 107 to ensure that the slot coating die 106 maintains its sealing and structural stability under high pressure. When the left and right die bodies are assembled into the slot coating die 106, the coating slots 1062 on both sides form a precision slot nozzle, through which the device continuously extrudes photoresist to form a nanoscale thin film on a high-speed moving substrate.

[0040] The top of the fixed frame 103 is equipped with a pneumatic self-locking online cleaning module 200, which is used to perform non-destructive cleaning of the slit coating die head 106 in the cleaning position.

[0041] like Figure 6 and Figure 7 As shown, specifically, the pneumatic self-locking online cleaning module 200 includes four second elastic telescopic rods 201 symmetrically fixed to the top wall of the fixed frame 103, with flexible docking cleaning nozzles 202 fixedly connected to their telescopic ends. Each second elastic telescopic rod 201 integrates a pre-tightening return spring, giving the flexible docking cleaning nozzle 202 axial floating capability, allowing it to fit tightly against the nozzle of the slit coating die head 106.

[0042] The flexible docking cleaning nozzle 202 has a high-pressure air inlet 204 on its front wall for connection to a high-pressure jet pipe; a contoured sealing docking groove 203 is provided at the bottom, the shape of which matches the slit nozzle of the slit coating die head 106 to ensure that the high-pressure gas is concentrated on the blocked area; independent exhaust micropores are evenly distributed around the rear wall, which are connected to an external independent negative pressure dust collection pipeline, specifically for discharging waste gas containing impurities and blown-off solid particles generated during purging. This sewage discharge path is completely independent of the negative pressure waste discharge channel 109. The former is used for the discharge of solid phase pollutants after cleaning, while the latter is used for the recovery of liquid phase residual adhesive before switching. The two have a clear division of labor, completely avoiding solid phase pollutants from mixing into the liquid phase recovery system or flowing back to the adhesive supply circuit.

[0043] A three-way manifold 302 is fixedly connected to the front wall of the fixed frame 103, and its rear end is tightly fitted to the high-pressure air inlet 204. The three-way manifold 302 is equipped with a follow-up air valve assembly 300 to control its opening and closing.

[0044] like Figure 8 and Figure 9 As shown, the follow-up vent valve assembly 300 includes a push-type reversing valve core 303 that is vertically slidably connected to the three-way manifold 302, and is connected to the top wall of the three-way manifold 302 by a linear return spring 305. A vent hole 304 is longitudinally formed inside the push-type reversing valve core 303. A cam guide block 301 is fixedly connected to the front side of each slit coating die 106, which is used to touch the push-type reversing valve core 303 when the slit coating die 106 reaches the cleaning position, triggering the air passage to open.

[0045] When the slit coating die 106 is in the upper cleaning position and fully reset, the upper surface of its cam guide block 301 tightly abuts against the bottom end of the push-type reversing valve core 303, overcoming the elastic force of the linear return spring 305 and pushing the push-type reversing valve core 303 to the high position. At this time, the vent 304 in the push-type reversing valve core 303 is precisely aligned with the main channel of the three-way manifold 302, and the external high-pressure air source can enter the flexible docking cleaning nozzle 202 through the three-way manifold 302, and the air path is in a ready-to-operate state. This design ensures that the air path is only opened after the slit coating die 106 is accurately in place and the flexible docking cleaning nozzle 202 and the nozzle have completed airtight docking, avoiding gas leakage or accidental spraying.

[0046] When the dual-position switching drive motor 111 drives the slit coating die head 106 to rotate away from this position, the cam guide block 301 disengages from the push-type reversing valve core 303, and the linear return spring 305 releases its elastic potential energy, quickly pushing the push-type reversing valve core 303 back to the low position. At this time, the vent 304 and the three-way manifold 302 are misaligned, and the air path is forcibly cut off to ensure that there is no high-pressure gas leakage when not in operation.

[0047] In the initial state, the positive pressure adhesive supply channel 108 is connected to the lower branch flow channel 113, and the negative pressure waste discharge channel 109 is connected to the upper branch flow channel 113. After the substrate to be coated is accurately transported to the coating station by the conveying assembly 102, the photoresist flows sequentially through the positive pressure adhesive supply channel 108 and the lower branch flow channel 113 under positive pressure, and enters the flow channel cavity 1061 of the lower slit coating die 106. Finally, it is continuously extruded through the precisely synthesized coating slit 1062, forming a uniform nanofilm on the high-speed moving substrate. At this time, the upper slit coating die 106 is in standby mode, with the cam guide block 301 on its front side abutting against the push-type reversing valve core 303 to keep it in a high position, and the follow-up vent valve assembly 300 in an open and ready state.

[0048] During the coating process, the pressure sensor monitors the flow channel pressure in real time. Once nozzle blockage is detected, causing abnormal pressure, the control system immediately activates the dual-position switching drive motor 111. The dual-position switching drive motor 111 drives the blind tube rotator 112 to rotate 180° counterclockwise, realizing the position swapping of the upper and lower slit coating die heads 106.

[0049] The previously spare clean slot coating die 106 is rotated downwards, and its branch channel 113 is aligned and connected with the positive pressure adhesive supply channel 108, allowing the coating operation to continue uninterrupted. The previously blocked slot coating die 106 is rotated upwards, and its branch channel 113 is aligned and connected with the negative pressure waste discharge channel 109. During rotation, the positioning protrusions on both sides of the slot coating die 106 slide from the outer convex section into the contraction section along the annular variable diameter guide groove 1041, forcing the two slot coating dies 106 to move inwards. At this time, the slot coating die 106 slides inwards along the branch channel 113, and the first elastic telescopic rod 110 adaptively contracts to avoid interference. After rotation to the correct position, the protrusions re-enter the outer convex section, and the slot coating die 106 resets outwards along the branch channel 113 under the constraint of the annular variable diameter guide groove 1041, ensuring that the distance between the nozzle and the substrate (or the flexible butt-fit cleaning nozzle 202) is constant and perpendicular.

[0050] To clean the clogging slit coating die head 106, a step-by-step strategy of "draining first, then purging, and independent sewage discharge" is adopted to completely prevent impurities from flowing back and contaminating the glue supply system.

[0051] When the clogged slit coating die 106 rotates to the upper cleaning position, its corresponding branch flow channel 113 first aligns and connects with the negative pressure waste discharge channel 109. The control system prioritizes activating the negative pressure unit to quickly draw the residual liquid photoresist inside the slit coating die 106 into a dedicated waste photoresist recovery tank, achieving preliminary emptying of the cavity inside the slit coating die 106. During this stage, the high-pressure air source is not activated to prevent liquid atomization and contamination diffusion.

[0052] After the liquid residue is drained, the slot coating die 106 precisely resets outward along the branch channel pipe 113. Its front cam guide block 301 abuts against the push-type reversing valve core 303 and slides it upward until the vent 304 is fully aligned with the three-way manifold 302, instantly opening the high-pressure air path. Simultaneously, the nozzle of the slot coating die 106 presses upward against the flexible butt-fit cleaning nozzle 202, causing the second elastic telescopic rod 201 to adaptively contract. The spring preload ensures a tight, airtight seal between the flexible butt-fit cleaning nozzle 202 and the nozzle of the slot coating die 106. Subsequently, high-pressure gas is pulsed into the coating slot 1062 through the high-pressure air inlet 204, forcefully blowing off the adhered cured particles and dried adhesive.

[0053] The waste gas and solid particles containing impurities generated during purging no longer flow back through the negative pressure exhaust channel 109. Instead, they are directly drawn into the industrial waste gas treatment system by the externally integrated negative pressure dust collection pipeline through the independent exhaust micro-holes pre-set on the rear wall of the flexible docking cleaning nozzle 202. This step-by-step cleaning strategy of "liquid phase negative pressure recovery and solid phase independent discharge" completely cuts off the path of cleaning contaminants flowing back to the precision glue supply circuit, effectively ensuring the cleanliness and long-term stability of the system.

[0054] After cleaning, the high-pressure air source is shut off. If the slit coating die 106 needs to be used again, the system can perform a solvent rinsing procedure. Subsequently, the slit coating die 106 remains in the upper standby position, and the cam guide block 301 continues to maintain the air path in a standby state, waiting for the next switching command. The entire process realizes a fully automated closed loop of "blockage detection - automatic switching - step-by-step cleaning - independent sewage discharge", significantly improving the overall efficiency of the equipment and the product yield.

[0055] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A photoresist coating apparatus, characterized in that, Including: Box (101); A conveying assembly (102) for transporting the substrate to be coated to the coating station is disposed on the housing (101); And an integrated coating and cleaning switching mechanism located above the housing (101); The coating and cleaning integrated switching mechanism includes: a rotary switching component for driving two slit coating dies (106) to switch between the coating station and the cleaning station; The adhesive supply and waste removal assembly is used to supply photoresist to the slit coating die (106) located at the coating station and to remove residual adhesive from the slit coating die (106) located at the cleaning station. The cleaning component is used to perform air jet cleaning on the slit coating die head (106) that has been switched to the cleaning station; and the control system controls the rotation switching component to operate according to the pressure detection signal, and starts the waste discharge and cleaning operations in sequence after switching, so as to automatically handle nozzle blockage without stopping the machine.

2. A photoresist coating apparatus according to claim 1, characterized in that, The rotary switching component includes: A fixed frame (103) is fixed to the top of the box (101), and guide supports (104) are symmetrically provided on the front and rear side walls of the fixed frame (103). A dual-position switching drive motor (111) is mounted on the rear guide support (104). A blind tube rotating body (112) is coaxially fixed to the output shaft of the dual-position switching drive motor (111). The blind tube rotating body (112) is a cylindrical shape with a closed rear end, and branch flow channels (113) are symmetrically arranged on its upper and lower sides and communicate with its inner cavity. And a dual-channel static manifold (105) fixed to the middle of the front guide support (104), the rear end of the dual-channel static manifold (105) extends into the cavity of the blind tube rotator (112) to form a rotational sealing coupling structure, and its outer diameter is precisely matched with the inner diameter of the blind tube rotator (112), allowing the blind tube rotator (112) to rotate freely around it.

3. A photoresist coating apparatus according to claim 2, characterized in that, The glue supply and waste discharge assembly includes a positive pressure glue supply channel (108) and a negative pressure waste discharge channel (109) arranged in parallel within the dual-channel static manifold (105). The positive pressure glue supply channel (108) is used to connect to the glue supply system, and the outlet end of the negative pressure waste discharge channel (109) is connected to an independent waste liquid recovery unit, which is physically isolated from the glue supply system; Two branch flow channels (113) are provided, which are respectively connected to the upper and lower slit coating die heads (106). When the blind tube rotator (112) rotates to the first working position, the lower branch flow channel (113) is connected to the positive pressure glue supply channel (108), and the upper branch flow channel (113) is connected to the negative pressure waste discharge channel (109). When the blind tube rotator (112) rotates 180° to the second working position, the upper and lower connections are interchanged.

4. A photoresist coating apparatus according to claim 2, characterized in that, Each slit coating die (106) is mounted on the corresponding branch channel pipe (113) and can slide along the axial direction of the branch channel pipe (113); each slit coating die (106) has a first elastic telescopic rod (110) symmetrically distributed along the branch channel pipe (113) fixedly connected on the side near the blind tube rotating body (112). The telescopic end of each first elastic telescopic rod (110) is fixedly connected to the blind tube rotating body (112) to buffer the radial displacement during the rotation process and assist in the reset.

5. A photoresist coating apparatus according to claim 4, characterized in that, Each slit coating die head (106) has a positioning protrusion on both the front and rear sides, and each guide support (104) has an annular variable diameter guide groove (1041) inside, and each positioning protrusion is embedded in the annular variable diameter guide groove (1041). The annular variable diameter guide groove (1041) has radially protruding sections on both the top and bottom sides, which are used to extend the slit coating die head (106) outward during the coating and cleaning stations to maintain a precise distance from the substrate and the cleaning parts; each annular variable diameter guide groove (1041) has a one-way anti-reverse right angle surface at the right corner of the top protruding section, which is used to force the slit coating die head (106) to rotate only counterclockwise, ensuring the certainty of the switching sequence.

6. A photoresist coating apparatus according to claim 1, characterized in that, The cleaning assembly is a pneumatically self-locking online cleaning module (200) mounted on top of a fixed frame (103), comprising: Four second elastic telescopic rods (201) are symmetrically fixed to the top wall of the fixed frame (103). The flexible docking cleaning nozzle (202) is fixed to the telescopic ends of the four second elastic telescopic rods (201). The second elastic telescopic rods (201) have pre-tightening reset springs integrated inside, which enables the flexible docking cleaning nozzle (202) to have axial floating capability. The front wall of the flexible docking cleaning nozzle (202) is provided with a high-pressure air inlet (204) for connecting to a high-pressure air source; the bottom is provided with a contour sealing docking groove (203) that matches the slit nozzle of the slit coating die head (106).

7. A photoresist coating apparatus according to claim 6, characterized in that, The flexible docking cleaning nozzle (202) has independent exhaust micro-holes evenly distributed along the circumference of the rear wall. The independent exhaust micro-holes are connected to the external independent negative pressure dust suction pipe and are used to discharge the waste gas containing impurities and solid particles generated by blowing. This sewage discharge path is independent of the negative pressure waste discharge channel (109).

8. A photoresist coating apparatus according to claim 6, characterized in that, It also includes a follow-up vent valve assembly (300) for controlling the on / off of the high-pressure gas path; the follow-up vent valve assembly (300) includes: The three-way manifold (302) is fixed to the front wall of the fixed frame (103), and its rear end is tightly fitted to the high-pressure air inlet (204); A push-type directional valve core (303) is vertically slidably connected to the three-way manifold (302), and is connected to the top wall of the three-way manifold (302) by a linear return spring (305); a vent hole (304) is opened in the push-type directional valve core (303) along the longitudinal direction. And the cam guide block (301) fixed to the front side of each slit coating die head (106), initially, the vent (304) is aligned with the main channel of the three-way manifold (302), the air path is open, and the linear return spring (305) is in a compressed state.

9. A photoresist coating apparatus according to any one of claims 1 to 8, characterized in that, Each slit coating die head (106) includes a left die body and a right die body that are connected to each other. A flow channel cavity (1061) for accommodating photoresist and a coating slit (1062) communicating with the outside are formed between the left die body and the right die body. The left die body and the right die body are fixedly connected by locking bolts (107).

Images