Chemical vapor deposition dry pump vacuum maintenance system

Abstract

The utility model provides a kind of chemical vapor deposition dry pump vacuum maintenance system, including vacuum pipe, first exhaust pipe and second exhaust pipe, vacuum pipe is connected with process cavity, pressure control butterfly valve is provided on vacuum pipe, the end of vacuum pipe away from process cavity has two flange surfaces, one flange surface is sealedly connected with a dry pump, first exhaust pipe is communicated with dry pump, another flange surface is sealedly connected with first blind plate, second exhaust pipe is sealedly connected with second blind plate;The opening of pressure control butterfly valve is at least 50 degrees.In the quantity of double dry pump reduces 50%, the utility model increases the opening of butterfly valve, so that the suction capacity of single pump can satisfy the suction capacity of original double pump.Compared with the double pump system in prior art, the utility model can directly reduce the cost of equipment procurement, reduce the floor area and daily maintenance amount and reduce 40% maintenance cost.At the same time, the energy consumption of dry pump is reduced by about 30%-40%, considerable electricity bill is saved annually, and carbon emission is effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of chemical vapor deposition equipment technology, and in particular to a chemical vapor deposition dry pump vacuum maintenance system. Background Technology

[0002] In the plasma-enhanced chemical vapor deposition process of display screen array factories Figure 1 This is a schematic diagram of the chemical vapor deposition (CVD) process. Figure 1 As shown, the existing chemical vapor deposition equipment includes a process chamber 20, inside which are an upper electrode 21 and a lower electrode 22. The process chamber is also connected to a pressure gauge 23. The dry pump vacuum maintenance system includes a vacuum tube 24 communicating with the process chamber. A pressure control butterfly valve 25 (with an opening degree of 45 degrees) is installed on the vacuum tube. The vacuum tube is also connected to two dry pumps 26.

[0003] The process requires the continuous removal of process gases 27 and byproducts 28 from the process chamber to maintain the optimal vacuum environment required by the process. This process is typically accomplished by a vacuum system consisting of multiple dry pumps. Due to the extremely high stability requirements of the process and the fact that the byproducts are mostly sticky dust, dry pump failures are common. Current designs generally adopt an "N+1" or "N+X" redundancy configuration scheme. N represents the number of dry pumps operating simultaneously in the process chamber, and X represents the number of redundant dry pumps.

[0004] In recent years, in particular, with the increasing consumer demand for large-size displays, larger-generation production equipment such as G8.5, G10, and G11 has become mainstream to meet the economic benefits of large-scale production. This development trend has placed more stringent requirements on vacuum systems.

[0005] To cope with the greater exhaust load resulting from larger process chambers, large-scale generation equipment typically equips each process chamber with a greater number of dry pumps, such as... Figure 2 The existing solutions shown have generally been upgraded from traditional single-pump systems to dual-pump systems or even more. That is, multiple dry pumps work simultaneously to meet the huge pumping speed requirements.

[0006] like Figure 2 The G6 generation chemical vapor deposition process chamber dry pump system, which includes one more dry pump than the G5 generation, has the following disadvantages: I. Initial investment and operating costs have risen sharply. Dry pumps are expensive and critical equipment. Upgrading equipment generations has led to an increase in the number of dry pumps required, which means that procurement costs and installation space costs are increasing linearly or even exponentially.

[0007] Second, the energy consumption is enormous, and the carbon emission problem is particularly prominent: dry pumps are major energy consumers in factories. For example, the energy consumption of a G6 generation array factory with a monthly production capacity of 30,000 units (e.g.) Figure 3As shown, the process chamber is equipped with dual dry pumps, with annual electricity costs of 3.65 million RMB, accounting for 9.6% of the total cost. As the number of dry pumps increases from 2 to 4 or more, the total power consumption becomes extremely high, and the long-term operation of multiple pumps makes electricity costs a heavy burden.

[0008] Third, system complexity and failure rate increase simultaneously. According to the "bathtub curve" law, the more equipment there is, the higher the statistical frequency of failures. The increase in the number of pumps directly leads to an increase in the number of system failure points. Maintenance personnel need to inspect, maintain, and repair more pumps more frequently, and spare parts inventory, maintenance, and management costs also increase significantly.

[0009] Fourth, and most seriously, it will exacerbate the damage caused by dust backflow pollution. For example... Figure 4 As shown, when one of the operating dry pumps suddenly fails and stops, the process chamber and vacuum pipeline remain under vacuum. At this time, the vacuum system will force the normally operating dry pump and vacuum valve to stop and close. This is to reduce the amount of dust (such as particulate matter) inside the failed dry pump 26B and its downstream exhaust pipe 29 that may be transferred by the other normally operating dry pump 26A. Figure 5 (As shown) Backflow contamination of the process chamber and even the transport chamber can lead to significant losses, rendering the entire machine unusable. However, because the other normally operating dry pump and vacuum valve take approximately 3-5 seconds to fully close from emergency stop, this momentary pressure imbalance is sufficient to cause dust 30 from the inside of the faulty dry pump and its downstream exhaust pipe to be backflowed into the clean process chamber by the normally operating dry pump, resulting in the substrate surface being covered with the reflowed dust 30, leading to product scrapping. For larger substrates with higher value (such as G8, 10.5, G11), once contamination occurs, the resulting scrapping of the entire chamber of substrates and the costly downtime for chamber cleaning will be even greater, with a more severe impact on yield and production efficiency. Utility Model Content

[0010] The technical problem to be solved by this utility model is to provide a chemical vapor deposition dry pump vacuum maintenance system, which reduces the number of dry pumps to achieve energy saving and consumption reduction, improve system reliability and eliminate the risk of dust backflow.

[0011] This utility model is implemented as follows: This utility model provides a chemical vapor deposition dry pump vacuum maintenance system, including a vacuum tube, a first exhaust pipe and a second exhaust pipe. The vacuum tube is connected to the process chamber. A pressure control butterfly valve is provided on the vacuum tube. The end of the vacuum tube away from the process chamber has two flange faces. One of the flange faces is sealed to a dry pump. The first exhaust pipe is connected to the dry pump. The other flange face is sealed to a first blind plate. The second exhaust pipe is sealed to a second blind plate. The opening degree of the pressure control butterfly valve is at least 50 degrees.

[0012] Furthermore, the first and second blind plates are made of SUS316.

[0013] Furthermore, a first bellows is provided between the vacuum tube and the dry pump. The two ends of the first bellows are respectively provided with a first sealing ring, and the two first sealing rings abut against the flange face of the vacuum tube and the flange face of the dry pump's air extraction port, respectively.

[0014] Furthermore, the exhaust port of the dry pump is connected to a second bellows, and the two ends of the second bellows are respectively provided with second sealing rings, and the two second sealing rings abut against the flange face of the first exhaust pipe and the flange face of the exhaust port of the dry pump.

[0015] Furthermore, a third sealing ring is provided between the first blind plate and the vacuum tube.

[0016] Furthermore, a fourth sealing ring is provided between the second blind flange and the second exhaust pipe.

[0017] The advantages of this utility model are: When the number of dual dry pumps is reduced by 50%, this invention increases the opening degree of the butterfly valve, enabling the suction capacity of a single pump to meet the original suction capacity of the dual pumps. Compared to existing dual-pump systems, this invention directly reduces equipment procurement costs, floor space, and daily maintenance and repair costs by 40%. Simultaneously, it reduces the energy consumption of the dry pumps by approximately 30%-40%, resulting in considerable annual electricity savings and effectively reducing carbon emissions.

[0018] Moreover, the single-pump system eliminates the risk of dust backflow contaminating the cavity, avoiding production losses of up to hundreds of thousands of yuan and improving product yield. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a schematic diagram of the cavity process in the existing chemical vapor deposition technology. Figure 2 Schematic diagram showing the number of dry pumps required for a chemical vapor deposition (CVD) system; Figure 3 This represents the percentage of electricity costs associated with the dual-pump vacuum maintenance system in the array manufacturing plant.

[0021] Figure 4 This is a schematic diagram of the structure in which dust backflow occurs when one of the dry pumps in the prior art fails.

[0022] Figure 5 This is a schematic diagram of the structure of this utility model.

[0023] Figure 6 This is a schematic diagram of the quality verification method after the dual-pump vacuum maintenance system is changed to a single-pump system according to this utility model.

[0024] Explanation of the labels in the diagram: 1. Vacuum tube; 2. First exhaust pipe; 3. Second exhaust pipe; 4. Pressure control butterfly valve; 5. Dry pump; 6. First blind flange; 7. Second blind flange; 8. First bellows; 9. First sealing ring; 10. Second bellows; 11. Second sealing ring; 12. Third sealing ring; 13. Fourth sealing ring; Detailed Implementation

[0025] Please see Figures 1 to 6 This utility model provides a chemical vapor deposition dry pump vacuum maintenance system, including a vacuum tube 1, a first exhaust pipe 2, and a second exhaust pipe 3. The vacuum tube 1 is connected to the process chamber. A pressure control butterfly valve 4 is provided on the vacuum tube 1. The maximum opening degree of the pressure control butterfly valve 4 is 100 degrees. The end of the vacuum tube 1 away from the process chamber has two flange faces. One of the flange faces is sealed to a dry pump 5. The first exhaust pipe 2 is connected to the dry pump 5. The other flange face is sealed to a first blind plate 6. The second exhaust pipe 3 is sealed to a second blind plate 7. The pressure control butterfly valve 4 has an opening of at least 50 degrees, and the increased opening of the pressure control butterfly valve 4 compensates for the pumping speed loss caused by the reduction of one pump.

[0026] Specifically, the first blind plate 6 and the second blind plate 7 are made of SUS316.

[0027] Specifically, a first bellows 8 is provided between the vacuum tube 1 and the dry pump 5. The two ends of the first bellows 8 are respectively provided with a first sealing ring 9, and the two first sealing rings 9 abut against the flange face of the vacuum tube 1 and the flange face of the air extraction port of the dry pump 5, respectively.

[0028] Specifically, the exhaust port of the dry pump 5 is connected to a second bellows 10, and the two ends of the second bellows 10 are respectively provided with second sealing rings 11. The two second sealing rings 11 abut against the flange face of the first exhaust pipe 2 and the flange face of the exhaust port of the dry pump 5.

[0029] Specifically, a third sealing ring 12 is also provided between the first blind plate 6 and the vacuum tube 1.

[0030] Specifically, a fourth sealing ring 13 is also provided between the second blind plate 7 and the second exhaust pipe 3.

[0031] Example 2: This utility model also provides a quality verification method for converting a dual-pump vacuum maintenance system into a single-pump system, including verification of vacuum degree and pressure control capability, verification of vacuum system sealing performance and ultimate vacuum degree, and verification of process quality and product performance.

[0032] 1. Verification of vacuum degree and pressure control capabilities Verification objective: To demonstrate that the pumping capacity and pressure control stability of the single-pump operation mode can fully meet the requirements of all predetermined processes.

[0033] Verification method: ① Under the same process recipe, record the pressure control curves of whether the process chamber reaches the set vacuum level and whether the required pressure is reached within the required time when running with dual pumps and single pumps respectively.

[0034] ② The pumping speed lost due to the reduction of one dry pump can be compensated by adjusting the pressure on the vacuum tube to control the opening of the butterfly valve.

[0035] Verification results: Experimental data show that for most processes, simply increasing the pressure control butterfly valve opening from 45 degrees to 50 degrees (the valve opening limit is 100 degrees) completely overlaps the pressure control curve and dynamic response speed in single-pump mode with the original dual-pump mode. This minor adjustment proves that the single pump has sufficient pumping capacity to cover all process pressure windows from the current pressure setting to high vacuum, fully meeting equipment requirements.

[0036] 2. Verification of vacuum system sealing performance and ultimate vacuum level Verification objective: To ensure that the vacuum sealing performance of the system is not affected after the modification, and to verify that its ultimate vacuum still meets the equipment standards. Verification method: Basic verification: During equipment maintenance, the ultimate vacuum of the modified system is measured using standard methods and compared with the data before the modification.

[0037] Advanced verification: ① Use a helium mass spectrometer leak detector to perform precise leak testing on all connections, including the modified vacuum pipeline and valve interfaces, to ensure that the leakage rate is still far below the equipment's specified safety threshold (e.g., less than 1×10⁻⁻⁴). 9 Pa・m³ / s ② Use an oxygen analyzer to perform precise leak detection at the blind flange interface of the exhaust pipe to ensure that the oxygen concentration is below the safety threshold specified by the equipment (e.g., less than 50 ppm). Verification results: The ultimate vacuum test results show that the values ​​before and after the modification are on the same order of magnitude, with no degradation.

[0038] The helium leak test confirmed that the seal was perfect and there was no leakage, proving the high standard and reliability of the hardware modification.

[0039] 3. Verification of process quality and product performance Verification objective: This is the most crucial verification, designed to prove that this technical solution will not have any negative impact on process results and product quality.

[0040] Verification method: All mass production process formulations were run in single-pump mode, and the following key parameters were intensively monitored and compared: Process stability parameters: plasma state (Vpp, Vdc), RF power stability, and pressure fluctuation range during the process.

[0041] Thin film characteristic parameters: film quality indicators such as refractive index and stress.

[0042] Product performance parameters: film thickness uniformity, key electrical parameters.

[0043] Final metrics: Product yield and results of passing reliability tests (such as high temperature and high humidity tests).

[0044] Verification results: ① All collected process stability parameters fluctuated within the same range before and after the modification, proving that the plasma environment is very stable.

[0045] ② Tests and analyses of the deposited thin film showed that its film quality, thickness uniformity, and various electrical parameters were not statistically significantly different from those before the modification.

[0046] ③Most importantly, the yield data of multiple batches of mass-produced products are completely on par with or even slightly improved from historical levels (due to the avoidance of defects caused by dust backflow); the product reliability test results are passed, which fully proves that the solution of this invention does not pose any risk to the long-term reliability of the product.

[0047] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A chemical vapor deposition dry pump vacuum maintenance system, comprising a vacuum tube, a first exhaust pipe, and a second exhaust pipe, wherein the vacuum tube is connected to a process chamber, a pressure control butterfly valve is provided on the vacuum tube, and the end of the vacuum tube away from the process chamber has two flange faces, characterized in that: One of the flanges is sealed to a dry pump, and the first exhaust pipe is connected to the dry pump; the other flange is sealed to a first blind flange, and the second exhaust pipe is sealed to a second blind flange. The opening degree of the pressure control butterfly valve is at least 50 degrees.

2. The chemical vapor deposition dry pump vacuum maintenance system as described in claim 1, characterized in that: The first and second blind plates are made of SUS316.

3. The chemical vapor deposition dry pump vacuum maintenance system as described in claim 1, characterized in that: A first bellows is also provided between the vacuum tube and the dry pump. The two ends of the first bellows are respectively provided with a first sealing ring, and the two first sealing rings abut against the flange face of the vacuum tube and the flange face of the dry pump's air extraction port, respectively.

4. The chemical vapor deposition dry pump vacuum maintenance system as described in claim 1, characterized in that: The exhaust port of the dry pump is connected to a second bellows, and the two ends of the second bellows are respectively provided with second sealing rings. The two second sealing rings abut against the flange face of the first exhaust pipe and the flange face of the exhaust port of the dry pump, respectively.

5. The chemical vapor deposition dry pump vacuum maintenance system as described in claim 1, characterized in that: A third sealing ring is also provided between the first blind plate and the vacuum tube.

6. The chemical vapor deposition dry pump vacuum maintenance system as described in claim 1, characterized in that: A fourth sealing ring is also provided between the second blind flange and the second exhaust pipe.

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