A method and system for hydrogen treatment using EUV process

Abstract

This application relates to a method and system for hydrogen treatment in an EUV process. The method is applied to the control device of an EUV process hydrogen treatment system, which includes a spray unit, a combustion unit, a combustion unit, and a tailpipe unit. The method includes: determining whether a trigger condition has been met based on real-time monitoring of the gas temperature in the spray unit and the gas concentration in the tailpipe unit; adjusting the external air supply from the combustion unit to the combustion unit based on the trigger condition; and simultaneously adjusting the amount of fuel gas supplied to the combustion unit based on the external air supply. This application can accurately track and respond to changes in the actual combustion state, ensuring uniform and stable combustion of hydrogen and combustion air within a wide flow range of 0-600 SLM. It effectively prevents safety risks such as unstable combustion, incomplete treatment, and even backfire and explosion, achieving a balance between treatment accuracy, safety, and economy.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and more specifically, to a method and system for hydrogen treatment in EUV process. Background Technology

[0002] EUV (Extreme Ultraviolet) lithography machines are used to manufacture chips with processes of 7nm, 5nm, 3nm and below. They use high-energy lasers to bombard tin droplets to generate extreme ultraviolet light with a wavelength of 13.5nm, which is then projected onto the wafer through a reflector to expose the circuit pattern.

[0003] The photolithography process requires a high-speed hydrogen gas flow (each machine can consume over 400 liters of hydrogen per minute) as a protective atmosphere and cleaning gas. This prevents the tin droplets used to generate EUV light from oxidizing. Simultaneously, the reactive free radicals generated by hydrogen continuously clean the reflective mirror surface, preventing carbon contamination and ensuring optical path stability. After completing its mission, the hydrogen gas is extracted by a vacuum pump. For safety reasons, it is typically mixed with approximately 50% nitrogen to form hydrogen-containing waste gas. Existing methods for treating hydrogen-containing waste gas mainly suffer from the following technical shortcomings: (1) It is flammable and explosive, with a wide explosive concentration range (4.0% - 75.6%). Within the explosive concentration range, a tiny electrostatic spark or a high-temperature surface is enough to trigger a catastrophic explosion. (2) The risk of backfire is high and it can easily lead to catastrophic accidents; (3) Due to the small size requirement of the equipment, the uniformity of hydrogen and air mixing, combustion stability and the ability to withstand sudden temperature drops are all huge challenges. (4) The process is complex. The hydrogen flow rate varies widely from 0 to 500 SLM, while the process N2 flow rate remains constant at 500 SLM. The waste gas concentration and flow rate change drastically in an instant, requiring the treatment system to have an ultra-fast response speed and extremely high control precision to prevent unstable combustion or incomplete treatment. Summary of the Invention

[0004] The purpose of this application is to provide a method and system for hydrogen treatment in EUV process, which can improve control accuracy and reduce equipment operating costs.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for hydrogen treatment in an EUV process and a control device for an EUV process hydrogen treatment system, wherein the EUV process hydrogen treatment system includes a spray unit, a combustion unit, a combustion unit, and an exhaust unit. The method includes: Based on the real-time monitoring of the gas temperature in the spray unit and the gas concentration in the exhaust unit, it is determined whether the triggering conditions have been met. Based on the triggering conditions, the external air supply from the combustion-supporting unit to the combustion unit is controlled and adjusted. At the same time, the amount of fuel gas supplied to the combustion unit is controlled and adjusted based on the external air supply.

[0006] In an optional embodiment, the spraying unit includes a spraying water tank, and a temperature sensor is installed inside the spraying water tank. The gas temperature monitored in real time includes the air temperature of the water tank detected by the temperature sensor. The tail exhaust unit includes a tail exhaust pipeline, and a hydrogen concentration sensor is installed inside the tail exhaust pipeline. The hydrogen concentration monitored in real time includes the tail exhaust hydrogen concentration detected by the hydrogen concentration sensor.

[0007] In an optional implementation, the triggering condition includes a comparison between the water tank temperature and / or the exhaust hydrogen concentration and a temperature threshold and / or an exhaust hydrogen concentration threshold. External air supply is introduced into the combustion unit through the combustion-supporting fan. Controlling and adjusting the external air supply from the combustion-supporting fan to the combustion unit includes controlling and adjusting the operating status of the combustion-supporting fan.

[0008] In an optional implementation, the temperature threshold includes a first temperature threshold, a second temperature threshold, and a third temperature threshold; The operating states of the combustion fan include high air volume operation, medium air volume operation and low air volume operation, and the first temperature threshold, the second temperature threshold and the third temperature threshold correspond to different operating states.

[0009] In an optional implementation, when the water tank temperature is lower than the first temperature threshold and the exhaust hydrogen concentration is lower than the exhaust hydrogen concentration threshold, the combustion fan is controlled and adjusted to operate in a low air volume state.

[0010] In an optional implementation, if the water tank temperature is higher than the first temperature threshold, or the exhaust hydrogen concentration is greater than the exhaust hydrogen concentration threshold and the water tank temperature is lower than the second temperature threshold, the combustion fan control switches to medium airflow operation.

[0011] In an optional implementation, if the water tank temperature is higher than the first temperature threshold, or the exhaust hydrogen concentration is higher than the exhaust hydrogen concentration threshold and the water tank temperature is higher than the second temperature threshold, the combustion fan control switches to high air volume operation. When the water tank temperature is lower than the third temperature threshold during high air volume operation, the combustion fan control switches to medium air volume operation.

[0012] In an optional embodiment, an air supply pipeline is provided between the combustion blower and the combustion unit, and an air supply regulating valve and an air supply flow meter are provided on the air supply pipeline. The combustion unit includes a fuel gas path, and a gas regulating valve and a gas flow meter are installed on the fuel gas path; The combustion-supporting fan, the temperature sensor, the hydrogen concentration sensor, the air-supporting regulating valve, the air-supporting flow meter, the gas regulating valve, and the gas flow meter are all electrically connected to the control device. The control device controls the operation of the combustion fan, the air supply regulating valve, and the gas regulating valve based on the received water tank temperature, exhaust hydrogen concentration, air supply flow rate, and gas flow rate.

[0013] Secondly, the present invention provides an EUV process hydrogen treatment system, employing the EUV process hydrogen treatment method described in any of the foregoing embodiments. The EUV process hydrogen treatment system further includes a molecular sieve unit, which is disposed between the combustion-supporting unit and the combustion unit.

[0014] In an optional embodiment, the combustion-supporting unit is located upstream of the molecular sieve unit, and the molecular sieve unit is connected to an air outlet duct. The combustion-supporting air passes through the molecular sieve unit and is then introduced into the combustion unit through the air outlet duct.

[0015] The EUV process hydrogen treatment method and system in this application can accurately track and respond to changes in the actual combustion state, ensuring uniform and stable combustion of hydrogen and combustion air within a wide flow range of 0-600 SLM. This effectively prevents safety risks such as unstable combustion, incomplete treatment, backfire, and explosion, achieving a balance between treatment accuracy, safety, and economy.

[0016] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an overall flow chart of the EUV process hydrogen treatment method in this application; Figure 2 This is the control logic diagram of the EUV process hydrogen treatment method in this application; Figure 3 This is a schematic diagram of the EUV process hydrogen treatment system in this application.

[0019] icon: 1-Spraying unit; 11-Spraying water tank; 12-Temperature sensor; 2-Combustion-supporting unit; 21-Combustion-supporting fan; 22-Air supply pipeline; 221-Air supply regulating valve; 222-Air supply flow meter; 3-Combustion unit; 31-Fuel gas passage; 311-Gas regulating valve; 312-Gas flow meter; 4- Tail exhaust unit; 41- Tail exhaust pipeline; 42- Hydrogen concentration sensor; 5-Molecular sieve unit; 51-Air outlet duct; 6-Control device. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0023] The EUV process hydrogen treatment method and system in this application specifically include a comprehensive treatment method for hydrogen-containing waste gas from the EUV process that is efficient, safe, and low-cost.

[0024] The EUV process hydrogen treatment method and system mainly abandons the traditional method of simply adjusting the air volume based solely on plant signals. Instead, it introduces process parameters such as gas temperature in the spray unit and gas concentration in the tail exhaust unit, which can comprehensively reflect the combustion state and treatment effect, as feedback parameters to adaptively and multi-stage adjust the combustion air volume.

[0025] This application enables stable, uniform, and safe combustion of hydrogen-containing waste gas over a wide flow range, and significantly reduces the equipment's own operating energy consumption and the generation of harmful byproducts such as nitrogen oxides.

[0026] Example 1 See Figure 1 This application provides a hydrogen treatment method for EUV process, and a control device 6 for EUV process hydrogen treatment system, wherein the EUV process hydrogen treatment system includes a spray unit 1, a combustion unit 2, a combustion unit 3 and an exhaust unit 4. The main steps of the EUV process hydrogen treatment method include: S1, real-time monitoring of the gas temperature in the spray unit 1 and the gas concentration in the tail exhaust unit 4.

[0027] S2 uses the monitored gas temperature and gas concentration as the basis for judgment to determine whether the preset triggering conditions have been met.

[0028] S3, based on the determined triggering conditions, adaptively controls and adjusts the external air supply from the combustion-supporting unit 2 to the combustion unit 3. At the same time, in order to ensure the completeness and stability of combustion, the amount of fuel gas introduced into the combustion unit 3 is controlled and adjusted in conjunction with the adjusted external air supply.

[0029] The EUV process hydrogen treatment method in this application uses the water tank temperature and the exhaust hydrogen concentration, two parameters that can directly reflect the internal heat load and treatment effect of the system, as control parameters to achieve closed-loop and graded regulation of the combustion air volume.

[0030] On the one hand, it solves the problem of control lag caused by drastic changes in hydrogen consumption and pipeline delays; on the other hand, it can dynamically match the minimum required air volume while ensuring safe handling.

[0031] The overall technical benefits are that it significantly reduces unnecessary plant air consumption and lowers the power consumption of the combustion fan 21. By precisely controlling the air / oxygen content required for combustion, the generation of thermal NOx is effectively suppressed; at the same time, it avoids excessive air entering the system, reduces the total gas flow and pressure in the system, improves hydrogen partial pressure and processing efficiency, and ultimately achieves a dual improvement in equipment stability and operational economy.

[0032] Example 2 Combination Figure 2, in one specific embodiment, in order to achieve high-precision and fast-response monitoring, the layout of key monitoring points is specifically set. Specifically, the spraying unit 1 includes a spraying water tank 11, and a temperature sensor 12 is arranged inside the spraying water tank 11. The gas temperature monitored in real time includes the water tank air temperature Tx detected by the temperature sensor 12, realizing the real-time monitoring of the water tank air temperature signal.

[0033] The tail gas exhaust unit 4 includes a tail gas exhaust pipeline 41, and a hydrogen concentration sensor 42 is arranged inside the tail gas exhaust pipeline 41. The hydrogen concentration monitored in real time includes the tail gas exhaust hydrogen concentration Hx detected by the hydrogen concentration sensor 42, realizing the real-time monitoring of the tail gas exhaust hydrogen concentration signal.

[0034] Based on the above two direct and reliable physical parameters as the control basis, it can accurately judge whether the combustion in the combustion unit 3 is sufficient, whether the system heat load is too high, and whether the treatment effect meets the standard.

[0035] Further, the triggering condition is specifically embodied as the comparison state between the monitored water tank air temperature Tx and / or the tail gas exhaust hydrogen concentration Hx and the pre-set air temperature threshold and / or the tail gas exhaust hydrogen concentration threshold. The external supplementary air volume is introduced into the combustion unit 3 through the combustion-supporting fan 21. Controlling and adjusting the external supplementary air volume of the combustion-supporting unit 2 to the combustion unit 3 includes controlling and adjusting the operating state of the combustion-supporting fan 21.

[0036] Based on the above, the external supplementary air volume is adjusted by controlling the operating state of the combustion-supporting fan 21. For example, when the air volume needs to be increased, the fan speed is increased, and vice versa, to adjust the external supplementary air volume of the combustion-supporting unit 2 to the combustion unit 3.

[0037] In this application, in order to be able to adapt to the drastic fluctuation of the hydrogen consumption of 0 - 600 SLM, this embodiment proposes a multi-stage air volume adjustment strategy.

[0038] In the specific adjustment process, multiple air temperature thresholds are pre-set, including the first air temperature threshold T1, the second air temperature threshold T2, and the third air temperature threshold T3, and the magnitude relationship among the three is T1 < T3 < T2. The first air temperature threshold, the second air temperature threshold, and the third air temperature threshold respectively correspond to different operating states. Correspondingly, the operating state of the combustion-supporting fan 21 is divided into three grades: high air volume, medium air volume, and low air volume.

[0039] In the specific control logic: Low air volume operating state: When it is monitored that the water tank air temperature Tx is lower than the first air temperature threshold T1 (i.e., Tx < T1), and the tail gas exhaust hydrogen concentration Hx is less than the pre-set tail gas exhaust hydrogen concentration threshold H1 (i.e., Hx < H1), it indicates that the system heat load is low and the combustion treatment is thorough, and there is no unburned hydrogen.

[0040] At this time, the control system determines that a large amount of air is not required, and switches or adjusts the combustion-supporting fan 21 to a low-air-volume operation state to maximize energy conservation and reduce NOx generation.

[0041] Medium-air-volume operation state: When any of the following conditions is met, that is, the water tank temperature Tx is higher than the first temperature threshold T1 (Tx > T1), or the hydrogen concentration Hx in the tail gas discharge is greater than the preset value H1 (Hx > H1), it indicates that the system heat load begins to increase or there is a tendency of incomplete hydrogen treatment.

[0042] On this premise, if the water tank temperature Tx has not exceeded the second temperature threshold T2 (i.e., Tx < T2), the system switches the combustion-supporting fan 21 to the medium-air-volume operation state to provide more oxygen to support combustion and prevent temperature runaway or hydrogen penetration.

[0043] High-air-volume operation state and hysteresis mode: When the water tank temperature Tx is higher than the first temperature threshold T1 (Tx > T1), or the hydrogen concentration Hx in the tail gas discharge is greater than the preset value H1 (Hx > H1), and the water tank temperature Tx further rises to exceed the second temperature threshold T2 (i.e., Tx > T2), it indicates that the system is in a high-load state and the air volume must be immediately increased to strengthen combustion and cooling.

[0044] At this time, the system switches the combustion-supporting fan 21 to the high-air-volume operation state. In the high-air-volume operation state, combustion will be strengthened, and the water tank temperature will decrease due to the increase in the externally supplemented air volume. To prevent the fan from frequently switching between high air volume and medium air volume (i.e., "oscillation"), this embodiment introduces a hysteresis logic: when in the high-air-volume operation state, when the water tank temperature Tx decreases and is lower than the third temperature threshold T3 (i.e., Tx < T3), the system switches the combustion-supporting fan 21 back to the high air volume from the medium air volume.

[0045] Since T3 is set to a value between T1 and T2 (T1 < T3 < T2), this hysteresis interval effectively ensures the stability of the control system.

[0046] Embodiment 3 Combined with Figure 3 , in this application, in order to achieve the precise control in Embodiment 2, a wind-assisting pipeline 22 is provided between the combustion-supporting fan 21 and the combustion unit 3 in this embodiment. A wind-assisting regulating valve 221 and a wind-assisting flowmeter 222 are installed on the wind-assisting pipeline 22. A gas regulating valve 311 and a gas flowmeter 312 are installed on the fuel gas pipeline 31 of the combustion unit 3. Methane for burning hydrogen in the waste gas is specifically introduced into the fuel gas pipeline 31, and the methane is introduced into the nozzle of the combustion unit 3 to burn the hydrogen in the waste gas through a high-temperature flame.

[0047] The combustion fan 21, temperature sensor 12, hydrogen concentration sensor 42, air supply regulating valve 221, air supply flow meter 222, gas regulating valve 311 and gas flow meter 312 are electrically connected to the control device 6 (such as PLC or DCS).

[0048] During operation, the control device 6 receives signals such as water tank temperature, exhaust hydrogen concentration, air supply flow rate, and gas flow rate in real time.

[0049] Its internal control logic (such as the multi-level judgment logic mentioned above) automatically calculates the target external air volume based on the received data and outputs commands to control the speed of the combustion fan 21 and / or the opening of the air regulating valve 221. At the same time, it precisely controls the opening of the gas regulating valve 311 through feedback from the gas flow meter 312 to ensure that the ratio of fuel gas to combustion air is always in the optimal combustion range under any air volume change, forming a complete and highly responsive closed-loop control system.

[0050] Example 4 Combination Figure 3 This application also provides an EUV process hydrogen treatment system, which adopts the above-mentioned EUV process hydrogen treatment method. The EUV process hydrogen treatment system specifically includes a spray unit 1, a combustion unit 2, a combustion unit 3, a tail exhaust unit 4, and a molecular sieve unit 5. The molecular sieve unit 5 is disposed between the combustion fan 21 and the combustion unit 3.

[0051] From the perspective of external combustion air and reducing nitrogen in the combustion air, the air supply pipe 22 is connected upstream of the molecular sieve unit 5. Ambient air is first blown into the molecular sieve unit 5 by the combustion air blower 21. After oxygen is separated by the molecular sieve, the oxygen-enriched air with significantly increased concentration is then introduced into the combustion unit 3 through the air outlet pipe 51.

[0052] Because the oxygen concentration in the combustion air is increased, more oxygen can be provided for hydrogen combustion without increasing or even decreasing the total air volume. This further reduces the total gas flow rate and pressure within the system, thereby more effectively improving the hydrogen concentration and processing efficiency within combustion unit 3.

[0053] At the same time, due to the reduction in the total amount of nitrogen, the generation of NOx under high-temperature combustion is also suppressed to a greater extent, achieving the technical effects of high efficiency, low consumption, and environmental protection.

[0054] The EUV process hydrogen treatment method and system in this application can effectively regulate the flow rate of the blower, methane fuel and combustion air according to the water tank temperature, thereby reducing equipment operating costs.

[0055] Molecular sieves are used to separate nitrogen from combustion air, reducing plant costs, increasing the partial pressure concentration of H2, and reducing NOx generation.

[0056] At the same time, it can improve control precision, reduce equipment operating costs, and adapt to the drastic fluctuations in hydrogen consumption from 0 to 600 SLM.

[0057] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.

[0058] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for hydrogen treatment using EUV process, characterized in that, A control device for an EUV process hydrogen treatment system, the EUV process hydrogen treatment system including a spray unit, a combustion unit, a combustion unit and an exhaust unit. The method includes: Based on the real-time monitoring of the gas temperature in the spray unit and the gas concentration in the exhaust unit, it is determined whether the triggering conditions have been met. Based on the triggering conditions, the external air supply from the combustion-supporting unit to the combustion unit is controlled and adjusted. At the same time, the amount of fuel gas supplied to the combustion unit is controlled and adjusted based on the external air supply.

2. The EUV process hydrogen treatment method according to claim 1, characterized in that, The spray unit includes a spray water tank, and a temperature sensor is installed inside the spray water tank. The gas temperature monitored in real time includes the air temperature of the water tank detected by the temperature sensor. The tail exhaust unit includes a tail exhaust pipeline, and a hydrogen concentration sensor is installed inside the tail exhaust pipeline. The hydrogen concentration monitored in real time includes the tail exhaust hydrogen concentration detected by the hydrogen concentration sensor.

3. The EUV process hydrogen treatment method according to claim 2, characterized in that, The triggering conditions include the comparison between the water tank temperature and / or the exhaust hydrogen concentration and the temperature threshold and / or the exhaust hydrogen concentration threshold. External air supply is introduced into the combustion unit through the combustion-supporting fan. Controlling and adjusting the external air supply from the combustion-supporting fan to the combustion unit includes controlling and adjusting the operating status of the combustion-supporting fan.

4. The EUV process hydrogen treatment method according to claim 3, characterized in that, The temperature thresholds include a first temperature threshold, a second temperature threshold, and a third temperature threshold; The operating states of the combustion fan include high air volume operation, medium air volume operation and low air volume operation, and the first temperature threshold, the second temperature threshold and the third temperature threshold correspond to different operating states.

5. The EUV process hydrogen treatment method according to claim 3, characterized in that, When the water tank temperature is lower than the first temperature threshold and the exhaust hydrogen concentration is lower than the exhaust hydrogen concentration threshold, the combustion fan control is adjusted to a low airflow operation state.

6. The EUV process hydrogen treatment method according to claim 3, characterized in that, If the water tank temperature is higher than the first temperature threshold, or the exhaust hydrogen concentration is greater than the exhaust hydrogen concentration threshold and the water tank temperature is lower than the second temperature threshold, the combustion fan control will switch to medium airflow operation.

7. The EUV process hydrogen treatment method according to claim 3, characterized in that, If the water tank temperature is higher than the first temperature threshold, or the exhaust hydrogen concentration is higher than the exhaust hydrogen concentration threshold, and the water tank temperature is higher than the second temperature threshold, the combustion fan control will switch to high air volume operation. When the water tank temperature is lower than the third temperature threshold during high air volume operation, the combustion fan control switches to medium air volume operation.

8. The EUV process hydrogen treatment method according to claim 3, characterized in that, An air supply pipeline is provided between the combustion blower and the combustion unit, and an air supply regulating valve and an air supply flow meter are provided on the air supply pipeline. The combustion unit includes a fuel gas path, and a gas regulating valve and a gas flow meter are installed on the fuel gas path; The combustion-supporting fan, the temperature sensor, the hydrogen concentration sensor, the air-supporting regulating valve, the air-supporting flow meter, the gas regulating valve, and the gas flow meter are all electrically connected to the control device. The control device controls the operation of the combustion fan, the air supply regulating valve, and the gas regulating valve based on the received water tank temperature, exhaust hydrogen concentration, air supply flow rate, and gas flow rate.

9. An EUV process hydrogen treatment system, employing the EUV process hydrogen treatment method according to any one of claims 1-8, characterized in that, The EUV process hydrogen treatment system also includes a molecular sieve unit, which is disposed between the combustion-supporting unit and the combustion unit.

10. The EUV process hydrogen processing system according to claim 9, characterized in that, The combustion-supporting unit is located upstream of the molecular sieve unit, and the molecular sieve unit is connected to an air outlet pipe. After passing through the molecular sieve unit, the combustion-supporting air is introduced into the combustion unit through the air outlet pipe.

Images