A photolithography machine proximal ultrapure water deep purification device and a photolithography machine water supply system

Abstract

The present invention relates to the field of ultrapure water purification technology, and discloses a photolithography machine proximal ultrapure water deep purification device and a photolithography machine water supply system, the photolithography machine proximal ultrapure water deep purification device comprising: a water supply line, a return line, a degassing component, a cross-flow microfilter and a photolithography machine liquid inlet line, the water outlet of the water supply line is connected to the water inlet of the first degassing component, the water outlet of the first degassing component is connected to the water inlet of the cross-flow microfilter, the return water port of the cross-flow microfilter is connected to the water inlet of the return line, the permeable water port of the cross-flow microfilter is connected to the photolithography machine liquid inlet line, and the second degassing component is on the return line and connected to the return water port of the cross-flow microfilter. Once the water flowing out of the return water port accidentally flows back or bacteria, particles, organic matter, dissolved oxygen, bubbles, etc. diffuse in reverse, they can still be separated and effectively prevented from entering the photolithography machine.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrapure water purification, and in particular to a device for deep purification of ultrapure water near the end of a photolithography machine and a water supply system for the photolithography machine. Background Art

[0002] With the development of the electronics and semiconductor industries, ultrapure water plays an increasingly important role in chip manufacturing, and the quality requirements for ultrapure water are becoming increasingly stringent.

[0003] Photolithography, which utilizes the photochemical reaction properties of photoresists to replicate designed circuit patterns onto silicon wafers, is a crucial technology in the integrated circuit manufacturing industry. Immersion lithography, also known as wet lithography, improves upon traditional dry lithography by placing a layer of immersion liquid between the lower surface of the final projection lens and the photoresist on the silicon wafer. This liquid increases the refractive index of the entire optical path. High-purity water is typically used as the immersion liquid. The immersion flow field formed by this high-purity water replaces the air at the center of traditional dry lithography. Because the refractive index of ultrapure water (1.44) is greater than that of air (1.00), this increases the numerical aperture of the lens assembly, resulting in smaller feature linewidths. In integrated circuit manufacturing, as chip feature sizes continue to shrink, immersion lithography places increasingly stringent requirements on the quality of the ultrapure water used in the production process. The presence of ions, dissolved oxygen, TOC, particulate matter, and bubbles in the immersion liquid can reduce the yield of integrated circuits. The introduction of liquid into the system is a fundamental characteristic of wet lithography. During the exposure process, the liquid between the projection lens and the silicon wafer becomes part of the optical path, effectively acting as the projection lens. Therefore, it requires extremely high cleanliness levels. The International Technology Roadmap for Semiconductors (ITRS) updated its ultrapure water quality requirements in its 2016 report, demonstrating that current ultrapure water quality requirements have reached their peak. Even with such extreme ultrapure water, even the slightest contamination can cause it to fail to meet wet lithography requirements.

[0004] According to the requirements of the 2012 edition of the International Technology Roadmap for Semiconductors (ITRS), the chapter "Improving Yield" includes two sub-chapters: "Wafer Environment and Contamination Control" (WECC) and "Qualification, Inspection, and Analysis" (CIA). Relevant content includes yield test structure methods, as well as data correlation, to determine the correlation between defects caused by the wafer production environment and processing output. This requires us to determine the cleanliness control limits of gases, chemicals, air, precursors, and substrate surfaces, including ultrapure water. With the continuous improvement of lithography technology and new manufacturing technologies, the corresponding effect of contamination control has become increasingly important in WECC, so the current new generation of lithography technology focuses more on extreme ultraviolet (EUV) technology and water contamination control.

[0005] When it comes to ultrapure water quality for VLSI (Very Large Scale Integrated Circuit) applications, priority water quality indicators include resistivity, particulates, TOC (total organic carbon), bacteria, soluble silicon, heavy metals, and dissolved oxygen (DO). These factors significantly impact semiconductor device production. During IC chip manufacturing, the more ions the medium in contact with the silicon wafer contains, the greater the impact on product yield. The ion concentration in ultrapure water can be characterized by resistivity. Particle count is also a measure of ultrapure water purity. If impurities or particulates are present in the cleaning water during the IC photolithography process, this can lead to uneven gate oxide film thickness and defects in the product pattern. Excessive particle content in the immersion liquid can also cause exposure defects. Trace amounts of organic matter in ultrapure water can affect the dielectric strength of the gate oxide film. The impact of bacteria in ultrapure water is similar to that of TOC and particulates, primarily because bacterial growth in the system creates a source of organic matter and particulates. Dissolved oxygen in ultrapure water accelerates oxidation reactions on the silicon wafer surface, leading to premature oxide film formation. The impact of bubbles is primarily due to the difference in refractive index between bubbles and ultrapure water. The refractive index of bubbles (1.00) is very different from that of ultrapure water (1.44). Bubbles in the ultrapure water inlet of the lithography machine can easily cause exposure defects in the lithography machine, which has a great impact on the chip manufacturing yield.

[0006] Existing ultrapure water for photolithography machines is typically produced by a remote ultrapure water system and then supplied through a co-located supply and return loop (hereinafter referred to as "LOOP"). Under current process methods, photolithography machines often share the same LOOP with other machines with different water quality requirements. These other machines often have lower ultrapure water quality requirements than the photolithography machines.

[0007] Currently, the ultrapure water feed for photolithography machines is typically produced in a remote ultrapure water system and then supplied through a co-flowing water supply and return loop (hereinafter referred to as "LOOP"). To maintain stringent ultrapure water quality standards, the LOOP uses an uninterrupted circulation state to simultaneously supply water to the photolithography machine and other equipment. Conventional technical means and process methods generally have the following three risks:

[0008] The first risk is secondary contamination from the loop. Loops can cause secondary contamination, and secondary contamination cannot be completely avoided. Appropriate technical measures can only be taken to delay and mitigate the extent of secondary contamination. Therefore, the actual quality of the ultrapure water inlet to the lithography machine is inferior to the quality of the water produced by the remote ultrapure water system, though the degree of degradation of various indicators varies. However, not all indicators present a significant risk of exceeding standards after degradation. LOOP pipelines, typically made of PVDF-HP material, exhibit low ion, silicon, and boron dissolution. Therefore, even with the presence of secondary contamination from the loop, when ultrapure water is transported from the remote system through the loop to the lithography machine inlet, its resistivity, silicon, and boron indicators generally still meet the requirements for the lithography machine inlet.

[0009] Generally, after LOOP secondary contamination, the main indicators that are likely to have adverse effects on the chip manufacturing yield of the lithography machine are bacteria, particles, TOC, dissolved oxygen and extremely small bubbles.

[0010] The first influencing indicator is bacteria. Conventional remote ultrapure water piping directly supplies the lithography machine through a loop (LOOP). This process can lead to secondary contamination through bacterial growth in the LOOP, posing a risk of excessive bacterial levels in the lithography machine's ultrapure water feed, which can negatively impact the chip manufacturing yield of the lithography machine. Typically, the bacterial content of the water produced by remote ultrapure water systems meets standards. However, bacterial growth in the LOOP cannot be completely avoided, and it will gradually increase with the age of the ultrapure water system and the LOOP. Bacterial growth in the LOOP can only be minimized through technical measures, such as using a co-flow design for the LOOP, controlling the ultrapure water flow rates in the main and branch lines of the LOOP, and minimizing dead water zones. Bacteria typically have a particle size exceeding 0.2 microns. Bacterial growth simultaneously generates new particles in the LOOP, so bacterial growth is often accompanied by an increase in particle size, or even exceeding standards. Furthermore, bacteria are organisms, and their metabolites and decomposition products are primarily organic matter. Bacterial growth can lead to an increase in TOC, or even the risk of exceeding standards. Conventional remote ultrapure water lines directly supply the lithography machine through a loop (LOOP). Bacteria can affect the chip manufacturing yield of the lithography machine. Although the water inlet requirements for other machines are less stringent than those for lithography machines, if the water inlet requirements of other machines still meet the standards but the water inlet requirements of the lithography machine exceed them, the loop must also be re-sterilized because it shares the same loop.

[0011] The second influencing indicator is particle size. Conventional processes, where ultrapure water is supplied directly to the photolithography machine through a loop (LOOP), introduce secondary particle contamination into the LOOP. This creates the risk of excessive particle levels in the lithography machine's ultrapure water feed, impacting the chip manufacturing yield of the machine. During the ultrapure water transfer process through the loop, some particles accumulate in the loop piping. Particle impact in the lithography machine's feed liquid comes from two sources: biological particles caused by bacterial growth and the re-emergence of particles deposited on the inner surface of the loop piping due to external vibrations and unexpected water hammer.

[0012] The third influencing indicator is TOC (Toxic Organic Compounds). Conventional remote ultrapure water lines directly supply the photolithography machine through a loop (LOOP). This process introduces secondary TOC contamination within the LOOP, putting the risk of TOC exceeding the standard in the photolithography machine's ultrapure water inlet, which in turn impacts the chip manufacturing yield of the photolithography machine. LOOP piping is typically constructed from Clean-PVC or PVDF-HP materials, which have low TOC dissolution rates. Therefore, the primary source of secondary TOC contamination is usually bacterial growth, not TOC dissolution from the LOOP piping.

[0013] A second risk associated with current conventional technologies and processes is the prolonged recovery time required for the ultrapure water inlet to the lithography machine after maintenance. During annual repairs and maintenance, the remote ultrapure water system's loop (LOOP) circulation is interrupted, leading to particle deposition and oxygen infiltration. Prolonged downtime can even lead to bacterial growth and TOC (Tocopherol) levels exceeding the lithography machine's ultrapure water inlet specification. If bacterial growth exceeds the lithography machine's ultrapure water inlet specification limit, the LOOP must be re-sterilized. After the ultrapure water system is restarted, it takes time for the lithography machine's ultrapure water inlet specification to recover. The ultrapure water in the loop needs to be fully replaced, and the deposited particles and dissolved oxygen must be circulated and replaced with fresh ultrapure water before the lithography machine's ultrapure water inlet specification can be met. Before the lithography machine's ultrapure water inlet specification reaches the standard, the ultrapure water inlet specifications of other machines have already met the standard.

[0014] The third risk of current conventional technical means and process methods is accidental backflow and reverse diffusion of pollutants. If there is accidental backflow or reverse diffusion of pollutants (dissolved oxygen, bubbles, bacteria, particles, organic matter) in the ultrapure water LOOP return line, the relatively poor water in the LOOP return line will enter the photolithography machine. Accidental backflow is often instantaneous. The reverse diffusion of pollutants can be either instantaneous or continuous. For example, bacteria have been found in practice to have the ability to grow against the water flow, and the phenomenon of them growing and spreading against the water flow from the return line to the water supply line does exist.

[0015] Current technology uses a traditional approach, installing a return line on the lithography machine's liquid supply line. This approach fails to address fault backflow and the reverse diffusion of secondary contamination indicators. When fault backflow or reverse diffusion occurs, contaminants such as bacteria, particles, and organic matter can enter the lithography machine. For example, related technologies employ a traditional approach, installing only a degassing membrane on the water supply line without addressing fault backflow and the reverse diffusion of secondary contamination indicators.

[0016] Based on the above analysis, theoretically, it is possible to consider placing the remote ultrapure water polishing system near the lithography machine. However, in practice, placing the remote ultrapure water polishing system near the lithography machine is difficult to achieve due to the following main practical factors:

[0017] a) The remote ultrapure water polishing system occupies a large area. It is economically unreasonable to occupy such a large polishing system in the clean space near the photolithography machine.

[0018] b) The vibrations generated by ultrapure water polishing systems significantly impact the normal operation of photolithography machines and other equipment within cleanrooms. To ensure a micro-vibration-free operating environment for these machines, it's not appropriate to locate the entire polishing system near them. Furthermore, vibration dampening the entire ultrapure water polishing system to meet micro-vibration requirements is prohibitively expensive and economically unjustifiable.

[0019] c) A single photolithography machine consumes very little water (e.g., 1-10 L / min), while the overall polishing system has a large production capacity. The difference in scale between the two can be thousands or even tens of thousands of times, creating a mismatch in scale. Using a separate, large-scale polishing system to process ultrapure water for the photolithography machine is illogical. Summary of the Invention

[0020] The invention discloses a device for deep purification of ultrapure water at the proximal end of a photolithography machine, which is used for alleviating secondary pollution caused by fault backflow and reverse diffusion of secondary pollution indicators.

[0021] To achieve the above object, the present invention provides the following technical solutions:

[0022] In the first aspect, a device for deep purification of ultrapure water proximal to a photolithography machine is provided, which comprises: a water supply pipeline, a return pipeline, a first degassing component, a cross-flow microfilter and a liquid inlet pipeline of the photolithography machine, the water outlet of the water supply pipeline is connected to the water inlet of the first degassing component, the water outlet of the first degassing component is connected to the water inlet of the cross-flow microfilter, the water return port of the cross-flow microfilter is connected to the water inlet of the return pipeline, and the permeate water port of the cross-flow microfilter is connected to the liquid inlet pipeline of the photolithography machine.

[0023] In the above-mentioned ultrapure water deep purification device near the photolithography machine, the first degassing component can effectively reduce the dissolved oxygen and bubbles in the ultrapure water supplied by the water supply pipeline; after the ultrapure water is degassed from the first degassing component, it enters the cross-flow microfilter. The water inlet and the return water outlet of the cross-flow microfilter are directly connected without a filter element, and the water between the two is in a flowing state. A filter element is provided between the permeate outlet and the path between the water inlet and the return water outlet. The water between the water inlet and the return water outlet enters the permeate outlet after passing through the filter element. The filter element filters out solid matter such as bacteria, particles and organic matter in the flowing ultrapure water. Moreover, regardless of whether the photolithography machine is in the ultrapure water inlet state, the ultrapure water from the water inlet to the return water outlet is in a flowing state, which reduces the risk of bacterial growth and is not easy to clog the filter element. At the same time, the intercepted bacteria, particles and some organic matter are re-processed with the return water. Once the water flowing out of the return water outlet accidentally backflows or bacteria, particles, organic matter, etc. diffuse in the reverse direction, the filter element can still retain them and effectively prevent them from entering the photolithography machine. The use of a cross-flow design instead of a dead-end filtration design can effectively reduce the accumulation of bacteria, particles, and organic matter on the filter surface, reduce the risk of exceeding the standard, and extend the service life of the filter.

[0024] Optionally, the photolithography machine proximal ultrapure water deep purification device further includes a second degassing component, which is connected between the water inlet of the reflux pipeline and the water return port of the cross-flow microfilter.

[0025] Optionally, the lithography machine proximal ultrapure water deep purification device further includes a shock absorbing device, and the first degassing component, the second degassing component and the cross-flow microfilter are arranged on the shock absorbing device.

[0026] Optionally, the lithography machine proximal ultrapure water deep purification device further includes a nitrogen supply pipeline, and the nitrogen supply pipeline is connected to the air inlet of the first degassing component and / or the air inlet of the second degassing component.

[0027] Optionally, the photolithography machine proximal ultrapure water deep purification device further includes a vacuum pump, and the air inlet of the vacuum pump is connected to the air exhaust port of the first degassing component and / or the air exhaust port of the second degassing component.

[0028] Optionally, the cross-flow microfilter is a cross-flow micro-ultrafiltration or a cross-flow micro-microfiltration.

[0029] Optionally, the filtration accuracy of the cross-flow microfiltration is 0.02 microns to 0.04 microns.

[0030] Optionally, a bypass valve is connected between the water outlet of the water supply pipeline and the water inlet of the return pipeline.

[0031] Optionally, the water supply pipeline, the pipeline between the water supply pipeline and the first degassing component, and the bypass valve are connected through a first tee; the return pipeline, the pipeline between the first degassing component and the water supply pipeline, and the bypass valve are connected through a second tee; wherein the bypass valve is directly in contact with the first tee and the second tee, respectively.

[0032] In a second aspect, a water supply system for a photolithography machine is provided, which includes: a remote ultrapure water pipeline and a proximal ultrapure water deep purification device for a photolithography machine as described in any of the above technical solutions, the remote ultrapure water pipeline includes a LOOP ultrapure water supply pipeline and a LOOP ultrapure water return pipeline, the LOOP ultrapure water supply pipeline is connected to the water supply pipeline, and the LOOP ultrapure water return pipeline is connected to the return pipeline.

[0033] The lithography machine near-end ultrapure water deep purification unit is a small deep purification device installed near the lithography machine. This deep purification utilizes the remote ultrapure water pipeline, rather than eliminating the remote ultrapure water system. This can address secondary contamination indicators in the loop that can adversely affect the lithography machine, thereby ensuring and improving the chip manufacturing yield of the lithography machine. For other effects, refer to the technical solution of the lithography machine near-end ultrapure water deep purification unit mentioned above. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the ultrapure water deep purification device near the lithography machine provided in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. A and / or B represent A, B, and A and B are three solutions in total.

[0036] refer to Figure 1, the photolithography machine proximal ultrapure water deep purification device provided in the embodiment of the present application includes: a water supply line L1, a return line L2, a first degassing component 1, a cross-flow microfilter 2 and a photolithography machine liquid inlet line L4, the water outlet of the water supply line L1 is connected to the water inlet of the first degassing component 1, the water outlet of the first degassing component 1 is connected to the water inlet of the cross-flow microfilter 2, the return water port of the cross-flow microfilter 2 is connected to the water inlet of the return line L2, and the water permeation port of the cross-flow microfilter 2 is connected to the photolithography machine liquid inlet line L4. The first degassing component 1 can adopt a micro degassing membrane. The first degassing component 1 is equipped with a degassing water inlet valve V1 upstream, and the first degassing component 1 is equipped with an air valve V7 and an air valve V8 respectively at its exhaust port, and a vacuum line L3 is used to connect the air valve V7 and the air valve V8 to evacuate the air, effectively reducing the dissolved oxygen and bubbles generated by the LOOP secondary pollution. The first degassing component 1 can be selected from molded products, such as 3M's MM1x5.5 and MM1.7x5.5 micro degassing membrane elements, and Cobetter's 1x3, 1x5.5, 2x6, 2x7, 2.5x8 and 4x13 micro degassing membrane elements.

[0037] In the above-mentioned ultrapure water deep purification device at the proximal end of the lithography machine, the first degassing component 1 can effectively reduce the dissolved oxygen and bubbles in the ultrapure water supplied by the water supply pipeline L1; the ultrapure water enters the cross-flow microfilter 2 after being degassed from the first degassing component 1, and the water inlet P1 and the return water port P2 of the cross-flow microfilter 2 are directly connected without a filter element. The water between the two is in a flowing state, and a filter element is provided between the water port P3 and the path between the water inlet P1 and the return water port P2. The water between the water inlet P1 and the return water port P2 enters the water port after passing through the filter element. At water inlet P3, the filter element removes solid matter such as bacteria, particles, and organic matter from the flowing ultrapure water. Furthermore, regardless of whether the lithography machine is receiving ultrapure water, the ultrapure water flowing from inlet P1 to return outlet P2 remains in a flowing state, reducing the risk of bacterial growth and preventing filter element clogging. Meanwhile, trapped bacteria, particles, and some organic matter are reprocessed with the return water. If the water flowing out of return outlet P2 unexpectedly backflows or reverses the diffusion of bacteria, particles, and organic matter, the filter element can still retain them, effectively preventing them from entering the lithography machine. The use of a cross-flow design, rather than a dead-end filtration design, effectively reduces the accumulation of bacteria, particles, and organic matter on the filter element surface, reduces the risk of exceeding standards, and extends the filter element's service life.

[0038] Secondary pollution also includes the following indicators, namely dissolved oxygen and bubbles.

[0039] Conventional remote ultrapure water lines supply the photolithography machine directly through a loop (LOOP). This process introduces secondary contamination with dissolved oxygen (DO) in the LOOP, posing a risk of excessive DO in the lithography machine's ultrapure water feed, which can negatively impact the chip manufacturing yield of the machine. In practice, we've found that even when the ultrapure water polishing system maintains a highly stringent DO standard of 1 ppb, and the LOOP is leak-free, the DO at the machine's water point can still rise significantly, even exceeding the standard. This demonstrates that the incorporation of DO into the LOOP is extremely difficult to control. Even if the LOOP is leak-free, oxygen from the air diffuses through the LOOP piping connections in minute amounts. While the resulting DO increase is only at trace levels (ppb) when the DO level is already extremely low, it's still significantly higher than the DO increase in the remote ultrapure water supply, potentially several times or even more severe.

[0040] Conventional remote ultrapure water lines supply the lithography machine directly through a loop (LOOP). This can introduce bubbles into the loop, impacting the chip manufacturing yield of the lithography machine. Some bubbles are initially attached to the loop and released into the water during vibration. Bubbles in ultrapure water can range from micrometers to millimeters in size. The refractive index of bubbles differs significantly from that of ultrapure water. Bubbles in the ultrapure water inlet of the lithography machine can easily cause exposure defects in the lithography machine, significantly impacting chip manufacturing yield.

[0041] To this end, in a specific embodiment, the ultrapure water deep purification device near the photolithography machine further includes a second degassing assembly 3, which is connected between the water inlet of the reflux line L2 and the return water outlet of the cross-flow microfilter 2. The second degassing assembly 3 can be a micro degassing membrane, and the details can be referred to the first degassing assembly 1. If there is unexpected backflow or reverse diffusion of dissolved oxygen, bubbles, etc. in the reflux line, the second degassing assembly 3 can effectively reduce the reverse flow of dissolved oxygen and bubbles, and effectively prevent them from entering the photolithography machine in the reverse direction. The downstream of the second degassing assembly 3 is equipped with a degassing reflux valve V4, equipped with air circuit valves V9, V10 and a vacuum pipeline for vacuuming. The air extraction port of the second degassing assembly 2 is respectively equipped with air circuit valves V9 and air circuit valves V10, and the vacuum pipeline L3 is connected to the air circuit valves V9 and air circuit valves V10 for vacuuming.

[0042] In one specific embodiment, the ultrapure water deep purification device near the photolithography machine also includes a vibration damping device. The first degassing assembly 1, the second degassing assembly 3, and the cross-flow microfilter 2 are mounted on the vibration damping device. This device can slow down the fluctuation of particles in the ultrapure water and reduce bubble formation, thereby minimizing the impact on the photolithography machine and meeting microseismic requirements.

[0043] When the water consumption changes, the number of the first degassing assembly 1, the second degassing assembly 3 and the cross-flow microfilter 2 can be increased or decreased accordingly.

[0044] In one specific embodiment, the apparatus for deep purification of ultrapure water near the photolithography machine further includes a nitrogen supply line connected to the air inlet of the first degassing assembly 1 (which can directly utilize its exhaust port as the air inlet) and / or the air inlet of the second degassing assembly 3 (which can directly utilize its exhaust port as the air inlet). This facilitates nitrogen replenishment to the ultrapure water, fully utilizing the exhaust ports of the first and second degassing assemblies 1 and 3 to supplement nitrogen, and thus simplifying the apparatus.

[0045] In a specific embodiment, the ultrapure water deep purification device near the photolithography machine further includes a vacuum pump, the air inlet of which is connected to the air extraction port of the first degassing component 1 and / or the air extraction port of the second degassing component 3. This allows for flexible vacuuming operations in situations where vacuuming conditions are unavailable.

[0046] In a specific embodiment, the cross-flow microfilter 2 is a cross-flow micro-ultrafiltration or a cross-flow micro-microfiltration. The cross-flow micro-ultrafiltration adopts a molecular weight of 10,000, which can effectively intercept bacteria and particles (bacterial particles are generally larger than 0.2 μm). The cross-flow micro-ultrafiltration can be a molded product, such as the FLT-1026 micro-ultrafiltration membrane element of ASAHI.

[0047] Cross-flow microfiltration can also intercept bacteria, particles and organic matter. When the filtration accuracy of cross-flow microfiltration is 0.02 microns to 0.04 microns, the interception effect is more obvious without increasing water resistance. The filtration accuracy of cross-flow microfiltration can be 0.02 microns, 0.03 microns or 0.04 microns.

[0048] A filter water inlet valve V2 is set between the first degassing component 1 and the water inlet P1 of the cross-flow microfilter 2, a filter return valve V3 is set between the return port P2 of the cross-flow microfilter 2 and the second degassing component 3, and a photolithography machine liquid inlet valve V6 is set on the photolithography machine liquid inlet pipeline L4.

[0049] In one specific embodiment, a bypass valve V5 is connected between the outlet of the water supply line L1 and the inlet of the return line L2. During normal operation of the device, bypass valve V5 is closed, and all valves V1 to V10, except bypass valve V5, are open to facilitate deep purification of ultrapure water. The purified ultrapure water then enters the photolithography machine via the photolithography machine inlet line L4. When maintenance of the device is required, bypass valve V5 is opened to at least close the degassing inlet valve V1 and the degassing return valve V4, short-circuiting the section between the degassing inlet valve V1 and the degassing return valve V4 to stop the device from purifying ultrapure water.

[0050] In one specific embodiment, the water supply line L1, the pipeline between the water supply line L1 and the first degassing assembly 1, and the bypass valve V5 are connected via a first tee. The return line L2, the pipeline between the first degassing assembly 1 and the water supply line L1, and the bypass valve V5 are connected via a second tee. The bypass valve V5 directly contacts the first and second tee, respectively. The bypass valve V5 features a design that minimizes dead angles on both sides of the tee. This ensures minimal dead water on both sides of the bypass valve when closed during normal operation, reducing bacterial contamination.

[0051] The above fully considers the effective response to fault backflow and reverse diffusion of major secondary pollution indicators, and improves the overall reliability of ultrapure water particles and organic matter indicators of the ultrapure water inlet of the lithography machine. The ultrapure water reflux is achieved by continuous flow of ultrapure water inside the cross-flow microfilter 2, and the ultrapure water is continuously refluxed through the water channel of the microfilter 2, instead of setting a reflux pipeline on the liquid supply pipeline of the lithography machine.

[0052] It mainly targets the indicators that are most likely to cause risks in LOOP secondary pollution (bacteria, particles, TOC, dissolved oxygen and bubbles), without considering ion indicators and other indicators that are less likely to cause risks, reducing the process complexity and equipment scale of the deep purification device and avoiding unnecessary cost waste.

[0053] The ultrapure water deep purification unit near the photolithography machine is tailored to the water volume requirements of the machine. Its size is appropriate, and its footprint is small, reducing the use of valuable space in the clean area where the machine is located. For example, using a 1L / min ultrapure water unit as an example, it only requires 0.6m*0.6m*0.8m of space.

[0054] The ultrapure water deep purification device near the photolithography machine uses a purely mechanical device, requiring no automatic control. This avoids complex operations and is simple to maintain, requiring minimal maintenance.

[0055] Based on the same inventive concept, an embodiment of the present application also provides a water supply system for a lithography machine, which includes: a remote ultrapure water pipeline and a proximal ultrapure water deep purification device for the lithography machine of the above embodiment, the remote ultrapure water pipeline includes a LOOP ultrapure water supply pipeline and a LOOP ultrapure water return pipeline, the LOOP ultrapure water supply pipeline is connected to the water supply pipeline L1, and the LOOP ultrapure water return pipeline is connected to the return pipeline L2.

[0056] The near-end ultrapure water purification unit for photolithography machines is a small-scale deep purification device installed near the photolithography machine. This deep purification utilizes the remote ultrapure water pipeline, rather than eliminating the remote ultrapure water system. It addresses secondary contamination in the loop that can adversely affect the photolithography machine, thereby ensuring and improving the chip manufacturing yield of the photolithography machine.

[0057] During the debugging and maintenance of the remote ultrapure water pipeline, the near-end ultrapure water deep purification device of the lithography machine can greatly reduce the waiting time for the ultrapure water inlet indicators of the lithography machine to quickly recover to the standard.

[0058] Based on the use of remote ultrapure water pipelines, a near-end ultrapure water deep purification device is installed near the lithography machine. This effectively reduces the main secondary contamination indicators in the loop that are likely to have adverse effects on the lithography machine, thereby ensuring and improving the lithography machine chip manufacturing yield.

[0059] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. A device for deep purification of ultrapure water near the end of a photolithography machine, characterized in that: The invention comprises: a water supply pipeline, a return pipeline, a first degassing component, a cross-flow microfilter and a liquid inlet pipeline of a photolithography machine, wherein the water outlet of the water supply pipeline is connected to the water inlet of the first degassing component, the water outlet of the first degassing component is connected to the water inlet of the cross-flow microfilter, the return water outlet of the cross-flow microfilter is connected to the water inlet of the return pipeline, and the permeate outlet of the cross-flow microfilter is connected to the liquid inlet pipeline of the photolithography machine; The photolithography machine proximal ultrapure water deep purification device further comprises a vacuum pipeline, and the vacuum pipeline is connected to the gas extraction port of the first degassing component; The photolithography machine proximal ultrapure water deep purification device further includes a second degassing component, which is connected between the water inlet of the reflux pipeline and the water return port of the cross-flow microfilter; No filter element is provided between the water inlet and the return water outlet of the cross-flow microfilter, and a filter element is provided between the water permeation outlet of the cross-flow microfilter and the path from the water inlet to the return water outlet; The device for deep purification of ultrapure water at the proximal end of a photolithography machine further includes a shock absorbing device, on which the first degassing component, the second degassing component and the cross-flow microfilter are arranged.

2. The device for deep purification of ultrapure water near the photolithography machine according to claim 1, characterized in that: The device for deep purification of ultrapure water at the proximal end of the lithography machine further includes a nitrogen supply pipeline, which is connected to the air inlet of the first degassing component and / or the air inlet of the second degassing component.

3. The device for deep purification of ultrapure water near the photolithography machine according to claim 1, characterized in that: The device for deep purification of ultrapure water near the photolithography machine further includes a vacuum pump, the air inlet of which is connected to the air exhaust port of the first degassing component and / or the air exhaust port of the second degassing component.

4. The device for deep purification of ultrapure water near the photolithography machine according to claim 1, characterized in that: The cross-flow micro filter is a cross-flow micro ultrafiltration or a cross-flow micro microfiltration.

5. The device for deep purification of ultrapure water near the photolithography machine according to claim 4, characterized in that: The filtration accuracy of cross-flow microfiltration is 0.02 micron to 0.04 micron.

6. The device for deep purification of ultrapure water near the photolithography machine according to claim 1, characterized in that: A bypass valve is connected between the water outlet of the water supply pipeline and the water inlet of the return pipeline.

7. The device for deep purification of ultrapure water near the photolithography machine according to claim 6, characterized in that: The water supply pipeline, the pipeline between the water supply pipeline and the first degassing component, and the bypass valve are connected through a first tee; The return line, the line between the second degassing assembly and the return line, and the bypass valve are connected via a second three-way connection; The bypass valve is directly in contact with the first three-way valve and the second three-way valve respectively.

8. A water supply system for a photolithography machine, characterized in that: include: The distal ultrapure water pipeline and the proximal ultrapure water deep purification device for a lithography machine according to any one of claims 1 to 7, wherein the distal ultrapure water pipeline comprises a LOOP ultrapure water supply pipeline and a LOOP ultrapure water return pipeline, the LOOP ultrapure water supply pipeline is connected to the water supply pipeline, and the LOOP ultrapure water return pipeline is connected to the return pipeline.

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