A developing solution tank concentration balancing system for LED chip manufacturing

Abstract

The utility model relates to a kind of developing liquid tank concentration balancing system for LED chip manufacturing, including stock solution pool, ultrapure water pool and developing liquid tank;It further includes concentration monitoring module, control unit and execution module;Concentration monitoring module includes the conductivity sensor and PH sensor of being arranged in developing liquid tank;Execution module includes first precision metering pump and second precision metering pump;First precision metering pump, second precision metering pump, conductivity sensor and PH sensor are electrically connected with control unit, by setting concentration monitoring module and control unit and execution module that conductivity sensor and PH sensor are composed, after detecting error, by control unit to execution module input instruction, inject accurate measurement liquid into developing liquid tank to maintain balance, the purpose of double perception, accurate diagnosis, real-time online and active prevention is realized by the cooperative monitoring of conductivity sensor plus PH sensor.

Description

Technical Field

[0001] This utility model relates to a concentration balancing system for a developer bath used in LED chip manufacturing, belonging to the field of LED chip manufacturing technology. Background Technology

[0002] In the manufacturing process of LED chips, photolithography is the core process for defining the key dimensions of the chip (such as electrodes, appearance structure, etc.). As a key process after photolithography, the stability of its quality directly affects the accuracy of the photolithographic pattern, and thus affects the luminous efficiency, wavelength consistency and yield of the LED chip. At present, the industry generally uses tank-type developing equipment, which immerses the wafers that have been spin-coated with photoresist and exposed into the developing solution tank for development.

[0003] Our company uses a method of manually injecting 25% stock solution into ultrapure water to reduce the concentration to 2.385% before introducing the mixture into the drug tank. The concentration is controlled by the number of tablets processed or the processing time, whichever comes first: the number of tablets processed is capped at 5500 or the processing time is 12 hours. No concentration control is performed during the process. The main disadvantages of this method are as follows: the concentration is prone to fluctuation in the later stages, affecting product quality. Although manual intervention is performed in the early stages, it cannot detect concentration deviations in a timely manner, resulting in delayed intervention. Moreover, manual intervention is also prone to problems such as inaccurate replenishment and poor consistency. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a concentration balancing system for a developer bath in LED chip manufacturing.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a concentration balancing system for a developing solution tank in LED chip manufacturing, comprising a stock solution tank, an ultrapure water tank and a developing solution tank, wherein the stock solution tank is connected to the developing solution tank through a first pipe and the ultrapure water tank is connected to the developing solution tank through a second pipe. It also includes a concentration monitoring module, a control unit, and an execution module; The concentration monitoring module includes a conductivity sensor and a pH sensor installed in the developer tank; The execution module includes a first precision metering pump installed on the first pipeline and a second precision metering pump installed on the second pipeline. The first precision metering pump and the second precision metering pump respectively deliver the developer stock solution from the stock solution tank and the ultrapure water from the ultrapure water tank to the developer tank as needed. The first precision metering pump, the second precision metering pump, the conductivity sensor, and the pH sensor are all electrically connected to the control unit.

[0006] Furthermore, a one-way valve is provided at the connection between the first pipe and the developer tank.

[0007] Furthermore, a one-way valve is provided at the connection between the second pipe and the developer tank.

[0008] Furthermore, the developing tank is also equipped with a drain pipe, and the drain pipe is equipped with a waste liquid discharge valve, which is electrically connected to the control unit.

[0009] Furthermore, the developing solution tank is also equipped with a pulsating device.

[0010] Compared with the prior art, the advantages and positive effects of this utility model are as follows: By setting up a concentration monitoring module, a control unit, and an execution module, the conductivity and pH sensors in the concentration monitoring module detect errors and, through the control unit, input instructions to the execution module to inject precisely measured amounts of liquid into the developing solution tank to maintain balance. The synergistic monitoring of the conductivity and pH sensors achieves the goals of dual sensing, accurate diagnosis, real-time online monitoring, and proactive prevention. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of a further embodiment of the present invention; Figure 3 This is a control diagram of the present invention; Legend: 1-Stock solution tank, 2-Ultrapure water tank, 3-First precision metering pump, 3.1-First pipeline, 4-Second precision metering pump, 4.1-Second pipeline, 5-Control unit, 6-Conductivity sensor, 7-pH sensor, 8-Developer tank, 8.1-Agitator, 9-Waste liquid discharge valve, 9.1-Drain pipe, 10-Check valve. Detailed Implementation

[0012] Please see Figure 1 and Figure 2 And refer to Figure 3 This utility model provides a technical solution: a concentration balancing system for a developer tank in LED chip manufacturing, including a stock solution tank 1, an ultrapure water tank 2, and a developer tank 8. The stock solution tank 1 is connected to the developer tank 8 through a first pipe 3.1, and the ultrapure water tank 2 is connected to the developer tank 8 through a second pipe 4.1. In order to prevent backflow, a one-way valve 10 is provided at the connection between the first pipe 3.1 and the second pipe 4.1 and the developer tank 8. It also includes a concentration monitoring module, a control unit 5, and an execution module. This control unit 5 uses a standard PLC control system; please see the control diagram below. Figure 3 ; The concentration monitoring module includes a conductivity sensor 6 and a pH sensor 7 installed in the developer tank 8; the conductivity sensor 6 is used to detect the conductivity of the developer in the developer tank 8, and the pH sensor 7 is used to detect the pH value of the developer in the developer tank 8, so as to achieve the purpose of real-time online detection of the quality of the developer. The execution module includes a first precision metering pump 3 installed on the first pipeline 3.1 and a second precision metering pump 4 installed on the second pipeline 4.1. The first precision metering pump 3 and the second precision metering pump 4 respectively deliver the developer stock solution in the stock solution tank 1 and the ultrapure water in the ultrapure water tank 2 to the developer tank 8 as needed. The first precision metering pump 3, the second precision metering pump 4, the conductivity sensor 6, and the pH sensor 7 are all electrically connected to the control unit.

[0013] To agitate the developer stock solution and ultrapure water added to the developer tank 8, a stirring device 8.1 is also provided in the developer tank 8. The stirring device 8.1 is used to agitate the developer stock solution and ultrapure water to achieve uniformity. The stirring device 8.1 is an aerator with an air supply pipe. One end of the air supply pipe is connected to the aerator, and the other end extends into the developer tank 8. The airflow generated by the aerator drives the developer stock solution and ultrapure water added to the developer tank 8 to agitate. The aerator is existing technology and can be purchased on the market.

[0014] Table 1 As can be seen from Table 1, after implementing this solution, the developer concentration can be maintained at 2.385% and the pH value can be maintained at 14 during the operation, which significantly improves the quality of the developer.

[0015] This solution sets up a concentration monitoring module, a control unit, and an execution module. When the conductivity sensor 6 and pH sensor 7 of the concentration monitoring module detect an error, the control unit 5 inputs a command to the execution module to inject a precisely measured amount of liquid into the developer tank 8 to maintain balance. The coordinated monitoring of the conductivity sensor 6 and pH sensor 7 achieves the goals of dual sensing, accurate diagnosis, real-time online monitoring, and proactive prevention.

[0016] To facilitate wastewater discharge, the developer tank 8 is also equipped with a wastewater discharge pipe 9.1, which is equipped with a waste liquid discharge valve 9. The waste liquid discharge valve 9 is electrically connected to the control unit 5.

[0017] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Variations and modifications made without departing from the spirit and scope of this utility model fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A developer bath concentration balancing system for LED chip manufacturing, characterized in that: It includes a stock solution tank (1), an ultrapure water tank (2) and a developer tank (8). The stock solution tank (1) is connected to the developer tank (8) through a first pipe (3.1), and the ultrapure water tank (2) is connected to the developer tank (8) through a second pipe (4.1). It also includes a concentration monitoring module, a control unit (5), and an execution module; The concentration monitoring module includes a conductivity sensor (6) and a pH sensor (7) installed in the developer tank (8). The execution module includes a first precision metering pump (3) installed on the first pipeline (3.1) and a second precision metering pump (4) installed on the second pipeline (4.1). The first precision metering pump (3) and the second precision metering pump (4) respectively transport the developer stock solution in the stock solution tank (1) and the ultrapure water in the ultrapure water tank (2) to the developer tank (8) as needed. The first precision metering pump (3), the second precision metering pump (4), the conductivity sensor (6) and the pH sensor (7) are all electrically connected to the control unit (5).

2. The developer bath concentration balancing system for LED chip manufacturing according to claim 1, characterized in that: A one-way valve (10) is provided at the connection between the first pipe (3.1) and the developer tank (8).

3. The developer bath concentration balancing system for LED chip manufacturing according to claim 1, characterized in that: A one-way valve (10) is provided at the connection between the second pipe (4.1) and the developer tank (8).

4. The developer bath concentration balancing system for LED chip manufacturing according to claim 1, characterized in that: The developer tank (8) is also provided with a drain pipe (9.1), and a waste liquid discharge valve (9) is provided on the drain pipe (9.1). The waste liquid discharge valve (9) is electrically connected to the control unit (5).

5. A developer bath concentration balancing system for LED chip manufacturing according to claim 1, characterized in that: The developer tank (8) is also equipped with a pulsating device (8.1).

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