Automatic blending and stirring system device for recycling photoresist

Abstract

The invention discloses an automatic blending and stirring system device for recycling photoresist. The automatic blending and stirring system device comprises a first stirring and mixing barrel, a second stirring and mixing barrel, a recycling and storing barrel, a new photoresist barrel and a control unit, wherein the first stirring and mixing barrel and the second stirring and mixing barrel are arranged in parallel. A liquid outlet of the recovery storage barrel is respectively connected with recovery liquid inlets of the first stirring and mixing barrel and the second stirring and mixing barrel through branch pipelines, and controlled liquid inlet valves are arranged on the two branch pipelines; the output end of the new photoresist barrel is connected to the new liquid inlets of the two stirring and mixing barrels through the pipelines with the valves respectively; liquid outlets of the two stirring and mixing barrels are connected into a main liquid supply pipeline in parallel, and a switching valve group is arranged on the pipeline to selectively communicate any stirring and mixing barrel to a downstream coating machine; and an online viscometer is mounted in each stirring and mixing barrel. The device has the advantages that automatic and continuous treatment and supply of the recovered photoresist liquid are realized through compact integrated layout in the cabinet and clear pipeline connection, and the device is compact in structure and convenient to transport, install and maintain.

Description

Technical Field

[0001] This invention relates to the field of semiconductor and flat panel display manufacturing equipment technology, and specifically to a system for the recovery, detection, automatic mixing and resupply of photoresist in the coating process. Background Technology

[0002] In the coating processes of semiconductors and panels, a large amount of expensive photoresist is wasted without being fully utilized. Existing recycling methods often employ a single stirred tank for simple processing, which has two major drawbacks: first, when the stirred tank is being adjusted for viscosity or undergoing maintenance, the system must stop supplying the coating machine, affecting production continuity; second, the mixing ratio of the recycled liquid to the new liquid relies on manual estimation or simple control, resulting in low precision and efficiency, making it difficult to ensure the recycled liquid's stable performance meets the requirements for recoating. Therefore, a recycling system capable of uninterrupted supply and automatic, precise mixing is needed. Summary of the Invention

[0003] The purpose of this invention is to provide a photoresist recycling and automatic mixing system device with a reasonable structural layout, continuous operation, and automatic and precise mixing.

[0004] To achieve the above objectives, the specific technical solution adopted by the present invention is as follows: The system is spatially divided into a storage area, a processing area, and a control area. The storage area houses new photoresist tanks (such as new liquid tanks) and diluent storage tanks; the processing area has a recycling storage tank, a first mixing tank, and a second mixing tank arranged side by side; the control area contains a control cabinet (control unit).

[0005] The positions and connections between the components are as follows: The core connection of the recycling storage tank: The recycling storage tank serves as the initial collection and mixing point for the recycled liquid. Its top has a main inlet for the recycled liquid, connecting to the recycling pipelines from each coating machine. At its bottom outlet, a transfer pump connects to the main outlet, which then branches upwards into two parallel branch pipes: the first branch extends horizontally to the left and then downwards to connect to the left inlet (first recycled liquid inlet) at the top of the first mixing tank; the second branch extends horizontally to the right and then downwards to connect to the left inlet (second recycled liquid inlet) at the top of the second mixing tank. A first inlet valve and a second inlet valve (such as a pneumatic ball valve) are installed in series on each branch.

[0006] The core connection of the new liquid supply unit is the output pump port of the new photoresist tank, which also branches into two parallel supply lines. One line connects to the right inlet (new liquid inlet) on the upper part of the first mixing tank, adjacent to the first recovered liquid inlet; the other line connects to the corresponding new liquid inlet on the upper part of the second mixing tank. A third inlet valve and a fourth inlet valve are installed on each line respectively.

[0007] The parallel output structure of the dual-stirring mixing tanks: The bottom outlets of the first and second stirring mixing tanks are each connected to an outlet pipe (the fifth and sixth pipes). These two outlet pipes extend vertically downwards for a short distance, then bend horizontally towards each other and merge, connecting to a common main supply pipe. A first outlet valve and a second outlet valve are installed on each outlet pipe before they merge. This structure ensures that the outputs of the two tanks are completely parallel in the fluid path, and the opening and closing of the valves determines which tank supplies the liquid.

[0008] Assembly of the detection components: A mounting hole is made in the upper part of the side wall of each mixing tank. The sensor probe of the online viscometer is fixed to this mounting hole by a flange or threaded sealing kit. Its probe extends horizontally into the inner cavity of the tank and is immersed below the working liquid surface to sense the liquid viscosity in real time.

[0009] Electrical connections of the control unit: The control unit (usually a PLC) is installed inside the control cabinet. Its analog input module is connected to the signal output terminals of two online viscometers via cables to read viscosity values. Its digital output module is connected to the electromagnetic control terminals of the first to fourth inlet valves, the first and second outlet valves, and the start / stop control terminals of each drive motor via cables, thereby driving these actuators to operate according to program instructions.

[0010] The entire system uses a closed or semi-closed cabinet as its load-bearing frame and external protection. The interior space of the cabinet is efficiently divided into two main functional areas, upper and lower.

[0011] The specific locations, connections, and mating relationships of each component within the cabinet are as follows: Lower processing area layout: Near the bottom of the cabinet, a horizontal mounting base (usually a steel frame or thick plate) is installed. On this base, five core tanks are arranged in a row from left to right according to the process flow, secured with bolts or special clamps: a new photoresist tank, a first mixing tank, a recovery storage tank, a second mixing tank, and a diluted cleaning solution storage tank. This layout ensures a clear flow of materials (new solution), processing units (dual mixing tanks), intermediate storage (recovery tank), and auxiliary units (diluted cleaning tank), minimizing pipeline connection paths.

[0012] Upper control area layout: The control components are installed in the upper space inside the cabinet, independent of the lower tank area. These components typically include electrical components such as PLC controllers, relays, power modules, and terminal blocks, all centrally mounted on an electrical mounting plate or standard rails at the top of the cabinet. This layered layout achieves relative separation between the dry area (electrical control) and the wet area (liquid handling), which is beneficial for safety and heat dissipation.

[0013] Internal piping layout: Valves, pumps, and pipes connecting the various tanks have been mostly connected and tested before leaving the factory. Piping is mainly laid and secured with clamps along pre-installed pipe grooves and supports on the inner walls of the cabinet's sides or rear wall, arranged neatly without occupying major maintenance space. All pipe connections are located in a visible and operable position on the front side of the cabinet.

[0014] Cabinet access structure: For ease of installation, commissioning, and maintenance, the entire front panel of the cabinet is designed as an openable access door. Preferably, a double-door structure is used, which, when opened, fully exposes all components inside the cabinet, providing a comprehensive, unobstructed operating passage. Observation windows, indicator lights, or touch screen human-machine interfaces can be installed on the doors.

[0015] Work process and beneficial effects: During system initialization, the control unit opens the first and third inlet valves, pumping a measured amount of recovered liquid and fresh liquid into the first mixing tank, and then starts its stirring motor for mixing. Simultaneously, the second mixing tank can be cleaned or kept in standby mode.

[0016] An online viscometer continuously monitors the viscosity inside the first mixing tank and feeds the data back to the control unit. The control unit determines whether fine-tuning or replenishment is needed based on a preset algorithm (such as PID control). When the photoresist liquid level in the first mixing tank reaches the required standard and the coating machine needs to supply liquid, the first outlet valve is opened, and the photoresist liquid is output through the main supply pipeline.

[0017] When the liquid level in the first mixing tank drops to a point where re-filling is required, the control unit, while maintaining its own liquid supply, opens the second and fourth inlet valves in advance to inject the next batch of slurry into the second mixing tank and begin mixing and testing. Once the mixture meets the required standards, the control unit first opens the second outlet valve and then closes the first outlet valve, achieving a seamless switch of the liquid supply source from the first tank to the second tank. Afterward, the first mixing tank can proceed to cleaning or the next round of material preparation.

[0018] This invention, through the aforementioned specific mechanical and pipeline structure of "dual tanks in parallel, independent inlet and outlet, and valve switching," coupled with automatic detection and control, achieves continuous online mixing and zero-interruption supply of recycled photoresist liquid, solving the inherent bottleneck of single-tank systems and significantly improving production efficiency and material utilization.

[0019] Modularity and portability: The entire system is a complete "equipment box". All internal assembly and testing are completed in the factory. After being transported to the site, it can be put into use simply by connecting an external power supply, a recovery input pipe and a liquid supply output pipe, which greatly reduces the amount of on-site installation work and time.

[0020] High space utilization: All components are compactly arranged in a cabinet, saving equipment floor space compared to scattered layouts, making it particularly suitable for cleanrooms or workshops with limited space. Easy maintenance: The front double door design allows operators to easily access all pumps, valves, tanks and electrical interfaces without moving equipment, enabling daily inspections, parts replacement or cleaning operations, making it highly maintainable.

[0021] Neat appearance and safety: All internal structures are enclosed in cabinets, resulting in a neat and aesthetically pleasing appearance. At the same time, it can effectively prevent external pollution and has a certain degree of safety protection. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the control and piping connections of the system of the present invention.

[0023] Figure 2 This is a schematic diagram of the overall structure of the system device of the present invention.

[0024] Figure 3 for Figure 2 A schematic diagram of the internal barrel assembly installation layout after a partial sectional view of the middle cabinet.

[0025] Figure 4 This is a vertical cross-sectional view of the second mixing tank in this invention.

[0026] (In the diagram: 1-New photoresist tank, 2-First mixing tank, 3-Recovery storage tank, 4-Second mixing tank, 5-Dilution cleaning solution storage tank, 6-Control components (PLC, etc.), 7-Online viscometer, 8-Drive motor, 9-Agitator blade, 10-Main liquid supply line, 11-Recovery liquid main inlet, 12-Recovery liquid branch line, 13-New liquid branch line, V1~V4-First to fourth inlet valves, V5, V6-First and second outlet valves, 100-Cabinet, 101-Bi-door maintenance door, 102-Observation window, 110-Mounting base plate, 120-Control component installation area.) Detailed Implementation

[0027] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein the same components are referred to by the same reference numerals.

[0028] like Figure 1-4 As shown, the recovery storage tank 3, the first mixing tank 2, and the second mixing tank 4 are arranged in a straight line. The recovery storage tank 3 is connected to a total recovery liquid inlet 11 at its upper end. A three-way pipe is connected to the outlet pump at the bottom of the recovery storage tank 3, forming two recovery liquid branches 12. The left branch, after passing through the first inlet valve V1, enters from the first recovery liquid interface at the upper left of the first mixing tank 2. The right branch, after passing through the second inlet valve V2, enters from the corresponding interface of the second mixing tank 4.

[0029] The new light-blocking tank 1 is located on one side of the system. Its pump outlet is also divided into two new liquid branches 13 through a three-way valve, which are connected to the new liquid inlets of the two mixing tanks via the third liquid inlet valve V3 and the fourth liquid inlet valve V4, respectively.

[0030] like Figure 4 As shown, taking the first mixing tank 2 as an example, a recovery liquid pipe joint and a new liquid pipe joint are welded to the upper side wall of the tank. The drive motor 8 is fixed to the center of the top of the tank via a frame, and the stirring shaft extends downward into the tank, with multiple layers of blades 9 installed at its end. The online viscometer 7 is horizontally inserted from the interface in the middle of the side wall of the tank.

[0031] The liquid outlets at the bottom of the first mixing tank 2 and the second mixing tank 4 are connected to the same main liquid supply pipeline 10 via pipes, after the first liquid outlet valve V5 and the second liquid outlet valve V6 are installed respectively.

[0032] The outlet of the diluent storage tank 5 is connected to the cleaning inlet of the first mixing tank 2 and the second mixing tank 4 via valved pipelines.

[0033] The integrated photoresist recycling and automatic mixing system consists of a vertical cabinet 100. The front of the cabinet 100 is equipped with a pair of double-leaf inspection doors 101 with observation windows 102.

[0034] After opening the access door 101, the entire interior of the cabinet can be seen (as shown in the image). Figure 2 , Figure 3 The lower part of the cabinet is a mounting base plate 110, on which, from left to right, are fixedly mounted a new photoresist tank 1, a first mixing tank 2, a recovery storage tank 3, a second mixing tank 4, and a diluted cleaning solution storage tank 5. The specifications of each tank can be selected according to capacity requirements, but the outer diameter should remain uniform or coordinated to ensure a neat layout.

[0035] The upper part of the cabinet is the control component installation area 120, which houses the control component 6, including a PLC and power supply. The control component 6 is electrically connected to the motors, sensors (such as viscometers), pumps, and valve groups on each tank in the lower layer via conduits or cable trays.

[0036] The piping system connecting each tank is mainly laid along the rear wall of the cabinet. For example, the pipe leading from the bottom of the recycling storage tank 3 splits into two branches at the rear, connecting forward to the first and second mixing tanks 2 and 4 respectively; the outlet pipe of the new photoresist tank 1 also branches at the rear and connects to the two mixing tanks. All manual or automatic valves are installed in positions that are easy to operate from the front.

[0037] During transport, closing and locking the access door 101 transforms the entire system into a robust transport unit. In field use, simply position the cabinet 100, connect the external piping and power supply, and the system can be started via the touchscreen or buttons on the cabinet door.

[0038] During operation, the control unit coordinates the opening and closing of various valves and the starting and stopping of the motor according to the preset program and viscosity feedback, driving the two mixing tanks 2 and 3 to work alternately according to the aforementioned process to achieve continuous liquid supply.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A photoresist recycling automatic blending and stirring system device, characterized in that, Comprise: Barrel assembly: including a recycling storage barrel, a first stirring mixing barrel and a second stirring mixing barrel; the first and second stirring mixing barrels are arranged side by side and have the same structure, each comprising a cylinder, a drive motor mounted on the top of the cylinder, a stirring shaft driven by the drive motor and a stirring paddle mounted on the lower part of the stirring shaft; the recycling storage barrel is also provided with a stirring mechanism; Pipeline and valve connection assembly: Recycling input pipeline: used to transport the recycled photoresist liquid of the external coating machine to the liquid inlet of the recycling storage barrel; First recycling branch: the liquid outlet of the recycling storage barrel is connected to the first recycling liquid inlet on the upper part of the first stirring mixing barrel cylinder through a first pipeline, and a first liquid inlet valve is installed on the first pipeline; Second recycling branch: the liquid outlet of the recycling storage barrel is connected to the second recycling liquid inlet on the upper part of the second stirring mixing barrel cylinder through a second pipeline, and a second liquid inlet valve is installed on the second pipeline; New liquid supply branch: a new photoresist barrel, whose output end is connected to the new liquid inlet of the first stirring mixing barrel through a third pipeline, and connected to the new liquid inlet of the second stirring mixing barrel through a fourth pipeline, and a third liquid inlet valve and a fourth liquid inlet valve are respectively installed on the third pipeline and the fourth pipeline; Liquid supply output pipeline: the liquid outlets at the bottom of the cylinder of the first and second stirring mixing barrels are connected in parallel to a main liquid supply pipeline through a fifth pipeline and a sixth pipeline, respectively, and a first liquid outlet valve and a second liquid outlet valve are respectively installed on the fifth pipeline and the sixth pipeline; the main liquid supply pipeline is used to supply photoresist liquid to the coating machine; Detection assembly: an online viscometer is installed inside the cylinder of the first and second stirring mixing barrels for real-time detection of the viscosity of the photoresist liquid in the barrel; Control assembly: a control unit, whose signal input end is electrically connected with the online viscometer, and whose control output end is electrically connected with the drive motor, the first to fourth liquid inlet valves, and the first and second liquid outlet valves.

2. The photoresist recycling and automatic dispensing and stirring system device according to claim 1, characterized in that: The liquid outlet at the bottom of the cylinder of the recycling storage barrel is divided into the first pipeline and the second pipeline through a main pipeline, forming a "one source and two supply" parallel branch structure.

3. The photoresist recycling and automatic dispensing and stirring system device according to claim 1 or 2, characterized in that: The first recycling liquid inlet and the new liquid inlet are respectively arranged on the upper part of the side wall of the cylinder of the first and second stirring mixing barrels, and are arranged adjacent to but independently of each other on the barrel body.

4. The photoresist recycling and recovery automated dispensing and stirring system of claim 1, wherein: The sensor probe of the online viscometer is vertically inserted into the side wall or the top of the cylinder of the stirring mixing barrel and extends below the liquid surface.

5. The photoresist recycling and automatic dispensing and stirring system of claim 1, wherein: The system further comprises a dilution liquid storage barrel, whose liquid outlet is connected to the cleaning inlet of the first and second stirring mixing barrels through a valve-equipped pipeline.

6. The photoresist recycling and recovery automated dispensing and stirring system of claim 1, wherein: The control unit is configured to control the opening and closing of the first liquid inlet valve, the third liquid inlet valve and the first liquid outlet valve, so that the first stirring mixing barrel is in an online working mode of "feeding-stirring-detecting-feeding"; at the same time, the second liquid inlet valve and the fourth liquid inlet valve are closed, and the second liquid outlet valve is opened, so that the second stirring mixing barrel is in a "preliminary emptying or cleaning" state, or vice versa; thereby realizing the alternating switching of the double-barrel working mode.

7. The photoresist recycling and automatic dispensing and stirring system of claim 1, wherein: Further comprising an integrated cabinet, and the following components are integrally installed in the cabinet: The new photoresist barrel, the first stirring and mixing barrel, the recovery and storage barrel, the second stirring and mixing barrel and the dilute cleaning solution storage barrel are sequentially arranged from left to right and fixedly installed on the same installation base plate below the inside of the cabinet body. The control assembly is installed above the inside of the cabinet body and is arranged in a spatially layered manner with the barrel assembly below. The cabinet body structure assembly is provided with an openable maintenance door on the front side, which provides an operation and maintenance channel for all the barrel assemblies, the pipeline and valve connection assemblies and the control assembly inside.

8. The integrated photoresist recycling and recovery automated dispensing and stirring system of claim 7, wherein: The maintenance door is a double-door structure.

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