A vacuum pump system, a vacuum system, and a method for generating a vacuum

Abstract

The invention relates to a vacuum pump system (10), comprising a plurality of pump stages (12) arranged in parallel, wherein an inlet (14) of each pump stage (12) of the plurality of pump stages (12) is connectable to a recipient (102); and an exhaust pump (30), wherein an outlet (26) of each pump stage (12) of the plurality of pump stages (12) is connected via a manifold (28) to an inlet (32) of the exhaust pump (30). Furthermore, the invention relates to a vacuum system and a method for generating a vacuum.

Description

[0001] A VACUUM PUMP SYSTEM, A VACUUM SYSTEM, AND A METHOD FOR GENERATING A VACUUM

[0002] The present invention relates to a vacuum pump system, a vacuum system, and a method for generating a vacuum.

[0003] Vacuum applications such as extreme ultraviolet lithography (EUV) systems in semiconductor production or direct-air capture (DAC) systems often use vacuum pump systems comprising a plurality of serially connected pump stages arranged in parallel housed in a frame. The inlets of the plurality of pump stages can be connected to the vacuum chamber, for example the extreme ultraviolet lithography vacuum chamber or the desorption chamber of a direct-air capture system, via a manifold that merges the inlets together.

[0004] These vacuum pump systems ensure effective vacuum generation. However, the systems have disadvantages in terms of efficiency, particularly power consumption.

[0005] Thus, it is an object of the present invention to provide a vacuum pump system, a vacuum system, and a method for generating a vacuum with improved efficiency, in particular a reduced power consumption.

[0006] The object is solved by a vacuum pump system according to claim 1, a vacuum system according to claim 14, and a method for generating a vacuum according to claim 15.

[0007] The vacuum pump system according to the invention comprises a plurality of serially connected pump stages arranged in parallel. An inlet of each pump stage of the plurality of pump stages is connectable, preferably directly or indirectly, to a recipient, for example via an inlet manifold. The recipient is preferably a vacuum chamber, more preferably an EUV vacuum chamber or a desorption chamber in a DAC system. The vacuum pump system further comprises an exhaust pump, wherein an outlet of each pump stage of the plurality of pump stages is connected via a manifold to an inlet of the exhaust pump. Preferably, the vacuum pump system comprises a single exhaust pump. The manifold preferably corresponds to the outlet of each of the pump stages and thus preferably to the outlet of the plurality of pump stages.

[0008] Preferably, the exhaust pump comprises or is a dry pump, particularly a multistage roots pump. For example, the exhaust pump can have three stages. It is preferred that the exhaust pump has a flow rate of at least 500 Standard Liters per Minute (slm) at 500 or less mbar. For example, an exhaust pump providing 750 slm at 300 mbar is preferred. The exhauster pump can be a single stage pump. On the other hand, exhauster pump can comprise multiple stages, particularly in EUV applications, for example in the case of the EUV vacuum chamber, and / or if hydrogen is pumped. More preferably, the exhauster pump has 3 or more stages, for example 3 to 6 stages. The exhaust pump preferably has an inlet pressure of 300mbar and / or a total delta_P of approximately 700mbar. The exhaust pump can have a capacity of 700 to 1500 slm, particularly in EUV applications.

[0009] Preferably, particularly if the recipient is a desorption chamber in a DAC system, the exhaust pump comprises or is a condenser pump, particularly a liquid ring pump. For example, the condenser pump can be a pump adapted to condense vapor, such as water vapor. A preferred example of the condenser pump is EHR.2190 by Edwards.

[0010] Preferably, the vacuum pump system comprises a housing, wherein the pump stages and the exhaust pump are arranged inside the housing. Particularly all pump stages, for example all pumps of the pump stages, and the exhaust pump are arranged inside the housing. The housing is particularly a frame, for example a EUV vacuum system frame or a DAC vacuum system frame. It is preferred that the vacuum pump system comprises a single housing. Preferably, the housing comprises a facility space, particularly a facility slice. A pump control system is preferably arranged inside the facility space. The pump control system particularly comprises a controller to control the pumps of the pump stages and / or electronics for the vacuum pump system, preferably the pumps of the pump stages. Further, it is preferred that the exhaust pump is arranged inside the facility space.

[0011] Preferably, the vacuum pump system comprises a controller to control the flow of fluid through and / or past the exhaust pump. Controlling the flow of fluid through the exhaust pump preferably means controlling the way it flows through the exhaust pump. Past the exhaust pump preferably means controlling the fluid flow to bypass the exhaust pump. The controller is particularly arranged inside the housing, for example inside the facility space. It is preferred that the controller is part of the pump control system.

[0012] Preferably, the vacuum pump system comprises a bypass connected to the manifold to selectively bypass the exhaust pump controlled by the controller. The bypass is particularly arranged inside the housing. The bypass is preferably adapted to bypass the fluid flow partly, mostly or completely around the exhaust pump. Preferably, the bypass comprises a valve, particularly a blow off valve and / or a relief valve, to selectively bypass the exhaust pump. The bypass, preferably the valve, can be connected to the atmosphere and / or a further exhaust system, for example a customer exhaust system.

[0013] Preferably, the controller is adapted to control the exhaust pump, particularly a speed of the exhaust pump. For example, the controller can be adapted to control the exhaust pump to a max speed and / or an idle speed.

[0014] Preferably, the controller is adapted to control fluid flow through or past the exhaust pump based on at least one of the following parameters: a fluid flow rate of the pump stages, a pressure in the manifold, a pressure at the outlet of the exhaust pump, or an identification of the pumped fluid, particularly of H2. For example, the controller is adapted to control fluid flow through or past the exhaust pump if an inlet flow rate of the vacuum pump system exceeds a threshold, such as a flow rate when the system is pumping down, on test, or if there is a leak. Preferably, the vacuum pump system comprises one or more sensors. The one or more sensors are particularly adapted to identify a pumped fluid, particularly to identify the presence of H2. Furthermore, the one or more sensors can be adapted to measure at least one of the following: a pressure in the manifold, a pressure at the inlet of the pump stages, a pressure at the outlet of the pump stages, a pressure at the inlet of the exhaust pump, a pressure at the outlet of the exhaust pump, a fluid flow rate in the manifold, a fluid flow rate at the inlet of the pump stages, a fluid flow rate at the outlet of the pump stages, a fluid flow rate at the inlet of the exhaust pump, and a fluid flow rate at the outlet of the exhaust pump. Particularly the controller is connected to the one or more sensors to control the fluid flow via the exhaust pump based on the sensor data. Alternatively or additionally, the controller can be adapted to control the fluid flow via the exhaust pump based on external inputs and / or information from the pump control system.

[0015] It is preferred that the controller is adapted to bypass the fluid flow if a pressure and / or a flow rate exceeds an upper limit and / or falls below a lower limit. For example, the controller can be adapted to bypass the fluid flow if the flow rate at the inlet of the pump stages F_total exceeds 120% of the nominal design capacity and / or falls below 50% of the nominal design capacity. F_total preferably corresponds to the sum of the inlet flow rate of all pump stages. Alternatively or additionally, the controller can be adapted to bypass the fluid flow if the pressure in the manifold P_manifold is smaller or equal to the pressure P_outlet at the outlet of the exhaust pump. Alternatively or additionally, the controller can be adapted to bypass the fluid flow if the pumped fluid does not comprise H2 or is not H2. Preferably the system comprises two bypasses, for example two duplicated bypasses. For example, the system can comprise a duplicated bypass valve and / or a duplicated controller and / or an automatic passive type of valve, for example a relief valve. The two bypasses are preferably fitted in parallel to ensure the system is fail-safe.

[0016] Preferably, each pump stage of the plurality of pump stages is a multistage pump stage comprising a plurality of pumps arranged in series. Particularly in the fluid flow direction of the pumps arranged in series each following pump has a smaller size and / or a lower capacity and / or a lower differential pressure than the previous pump.

[0017] Preferably, each pump stage of the plurality of pump stages comprises a primary booster pump, particularly a mechanical booster pump. It is preferred that the primary booster pump, preferably its inlet, is directly connected to the inlet of the pump stages, for example to the inlet manifold. The primary booster is preferably a single stage roots-type high vacuum booster, particularly with capacity >10,000 m3 / hr.

[0018] Preferably, each pump stage of the plurality of pump stages comprises a secondary booster pump, particularly a small booster pump. The secondary booster pump is particularly an intermediate booster pump and / or a low booster pump. The second booster is preferably a single stage or a two-stage roots type, particularly with a capacity of Vi or less than Vi that of the primary booster pump, preferably so that a volume ratio exceeding 2 between the primary and secondary booster is achieved.

[0019] Preferably, each pump stage of the plurality of pump stages comprises a third, particularly a backing pump. The third pump is preferably a 'primary pump' or a 'fore pump'. The third pump can be a multistage dry pump. Particularly the third pump is a multistage roots-type, a multi-stage claw pump, a combination of roots and claw, or a screw-type vacuum pump. For example, the third pump can have a capacity of 500m3 / hr.

[0020] The following connection, preferably direct connection, of the pumps in each pump stage is preferred: the inlet of each pump stage is connected to the inlet of the primary booster pump, the outlet of the primary booster pump is connected to the inlet of the secondary booster pump, the outlet of the secondary booster pump is connected to the inlet of the backing pump, and / or the outlet of the backing pump is connected to the outlet of the plurality of pump stages and / or to the manifold. If one or more of these pumps are missing in a pump stage, the other pumps are connected correspondingly. The inlet of the exhaust pump is preferably connected to the manifold, particularly the outlet of the manifold and / or the outlet of the pump stages. Preferably each pump stage of the plurality of pump stages comprises a primary booster pump, a secondary booster pump and a backing pump arranged in series.

[0021] Preferably, an outlet of the exhaust pump is, particularly directly, connected to the atmosphere and / or a further exhaust system, for example a customer exhaust system.

[0022] The vacuum system according to the invention is particularly an EUV system or a DAC system. The system comprises a chamber. The chamber is preferably a vacuum chamber, more preferably an EUV vacuum chamber or a desorption chamber in a DAC system. The system further comprises a vacuum pump system according to the invention connected to the chamber, preferably to generate a vacuum in the chamber. If the system is a EUV system, the system comprises a EUV vacuum chamber, wherein optical components of the EUV and / or wafers of which patterns with the EUV are to be generated on are arranged inside the vacuum chamber. The optical components are, for example, a light source, a mirror, preferably a EUV collector mirror, more preferably a plurality of this mirror, and / or a mask. If the system is a DAC system, the system comprises one or more DAC chambers. The one or more DAC chambers can be, for example, a desorption chamber, a compression chamber for compressing the fluids pumped out of the desorption chamber, and / or a storage chamber for storing the fluids pumped out of the desorption chamber. The fluid in the DAC system is preferably CO2. Particularly the desorption chamber contains sorbents and / or solvents to capture CO2. It is preferred that the desorption chamber is, particularly selectively openable, connected to the atmosphere.

[0023] The method according to the invention is preferably a method for generating a vacuum. To generate the vacuum a vacuum pump system according to the invention or a vacuum system according to the invention is used. More preferably, the method is a method for producing semiconductors or a method for DAC, particularly for capturing CO2. The method for producing semiconductors uses EUV, preferably a EUV system is used to perform the method. The vacuum for the application of the EUV is preferably generated by a vacuum pump system according to the invention or a vacuum system according to the invention. The method for capturing CO2 preferably uses a vacuum pump system according to the invention or a vacuum system according to the invention. The vacuum pump system or the vacuum system is preferably used to regenerate sorbents and / or solvents which capture, particularly adsorb and / or absorb, CO2. Alternatively or in addition, the vacuum pump system or the vacuum system can be used to collect the captured CO2 for storage. Alternatively or in addition, the vacuum pump system or the vacuum system can be used to pass, particularly atmospheric, air through the desorption chamber, particularly through a capture unit containing the sorbents and / or the solvents in the desorption chamber.

[0024] In the following the present invention is described in more detail with reference to the accompanying drawings.

[0025] The figures show: Figure 1 a schematic view of an embodiment of a vacuum pump system according to the invention, and

[0026] Figure 2 a schematic view of an embodiment of a vacuum system according to the invention comprising a further embodiment of a vacuum pump system according to the invention.

[0027] Figure 1 shows a schematic view of an embodiment of a vacuum pump system 10.

[0028] The vacuum pump system 10 comprises a plurality of pump stages 12 arranged in parallel. The inlets 14 of each pump stage 12 are connected via an inlet manifold 16 to an inlet 18 of the vacuum pump system 10. A recipient 102 (not shown), such as a vacuum chamber, for example a EUV vacuum chamber or a desorption chamber of a DAC system, can be connected to the inlet 18, particularly to be evacuated by the vacuum pump system 10.

[0029] Each pump stage 12 preferably comprises a primary booster pump 20, a secondary booster pump 22 and a backing pump 24 arranged in series.

[0030] The outlets 26 of each pump stage 12 are connected to an inlet 32 of an exhaust pump 30 via a manifold 28. The exhaust pump 30 can comprise or be a dry pump, particularly a multistage roots pump. For example, the exhaust pump 30 can have three stages. It is preferred that the exhaust pump 30 has a flow rate of at least 500 Standard Liters per Minute (slm) at 500 or less mbar. For example, an exhaust pump 30 providing 750 slm at 300 mbar is preferred. Alternatively or additionally, the exhaust pump 30 can comprise or be a condenser pump, particularly a liquid ring pump. For example, the condenser pump can be a pump adapted to condense vapor, such as water vapor. A preferred example of the condenser pump is EHR.2190 by Edwards. A bypass 36 is connected to the manifold 28 to selectively bypass the exhaust pump 30. The bypass 36 is preferably adapted to bypass the fluid flow partly, mostly or completely around the exhaust pump 30. The bypass 36 comprises a valve 38, particularly a blow off valve, to selectively bypass the exhaust pump 30. The outlet 34 of the exhaust pump 30 and / or the bypass 36 are preferably connected to a further exhaust system (not shown) or can be open to the atmosphere 35. The further exhaust system can vent to the atmosphere downstream. For example, the further exhaust system can comprise an abatement system, or a recovery system to recover the gases for recycling.

[0031] A controller 40 is connected to the exhaust pump 30 and the bypass 36, preferably the valve 38, to control the exhaust pump 30 and the bypass 36. For example, the controller 40 can be adapted to control a speed of the exhaust pump 30, such as controlling the exhaust pump to a max speed and / or an idle speed. Furthermore, the controller can be adapted to control the valve, for example, partially open the valve 38, fully open the valve 38 and / or close the valve 38.

[0032] The controller 40 can be connected, wired or wirelessly, to one or more sensors 42, 44, 46 and / or to a (not shown) pump control system to control the pump stages 12 and / or to an external, for example manual, (not shown) input device.

[0033] In the shown embodiment, the controller 40 is connected to a flow rate sensor 44 adapted to measure the flow rate F_total in the manifold 16, particularly the inlet flow rate of the vacuum pump system 10. Furthermore, the controller is connected to a pressure sensor 42 measuring the pressure P_manifold at the inlet 32 of the exhaust pump 30 and / or in the manifold 28, and the controller 40 is connected to a pressure sensor 42 measuring the pressure P_outlet at the outlet 34 of the exhaust pump 30. Additionally, the controller 40 is connected to a sensor sensing the flowing fluid, particularly sensing if the flowing fluid does not contain or is not H2. It is preferred that the controller 40 is adapted to control the valve 38 and / or the exhaust pump 30 based on the detected results of the sensors 42, 44, 46. For example, controlling can be implemented if F_total exceeds a predetermined flow rate and / or falls below a predetermined flow rate; and / or if the pressure in P_manifold is smaller or equal to the pressure P_outlet at the outlet of the exhaust pump 30; and / or if the pumped fluid does not comprise H2 or is not H2.

[0034] With such inventive arrangement the efficiency, particularly the power consumption, of a vacuum pump system 10 can be improved.

[0035] For example, it was found that pump power at ultimate and low pressures is largely influenced by the pressure differential and capacity of the final stage of the pump exhausting to atmosphere. For example, making a pump with a very small stage in relation to the inlet stage, i.e. high-volume ratio, can give lower ultimate and low-pressure power.

[0036] With the embodiment, particularly the invention, it is possible to reduce the power consumed during processing at low inlet pressures by adding a single exhaust pump to the system exhaust. This lowers the primary-pump power considerably and adds the power of only a single, preferably small, exhaust pump, whereby a total net power saving can be achieved.

[0037] The following results were found in an experimental example based on the invention, particularly the embodiment.

[0038] For each pump stage 12 a primary booster pump 20, a secondary booster pump 22, and a backing pump 24 was used.

[0039] An exhaust pump 30 adapted for 750slm, at 300mbar, for example a dry-pump was used. For the backing pump 24 ('Pump'), on H2, with no purge, @120Hz with different exhaust pressures the following values (Table 1) were detected at 150slm per pump.

[0040]

[0041] Table 1: Power of Pump (backing pump) based on pressure

[0042] As can be seen in Table 1, the reduced exhaust pressure of 300mbar at the backing pump 24 ('Pump') due to the exhaust pump 30, compared to a standard pressure, i.e. atmospheric pressure, of 1000 mbar, led to a power saving of 2.75 kW (6.8 kW - 4.05) per backing pump 24. Since five backing pumps 24 were used, the total power saving for the backing pumps 24 is 13.75 kW (2.75 kW *5).

[0043] The following Table 2 shows the power consumption of the exhaust pump 30.

[0044]

[0045] Table 2: Power of exhaust pump

[0046] As can be seen in Table 2, the power consumption of the exhaust pump is approximately between 4914 W and 4875.5 W, i.e. around 4.9 kW. Thus, with this additional power usage, the total net saving for the vacuum pump system 10 based on the inventive approach is around 8.85 kW (13.75 kW - 4.9 kW).

[0047] Figure 2 shows a schematic view of an embodiment of a vacuum system 100 comprising a further embodiment of a vacuum pump system 10.

[0048] The vacuum pump system 10 comprises a housing 48, for example a frame, such as a EUV vacuum system frame or a DAC vacuum system frame, having six spaces 50a, 50b, particularly slices, to house components of the vacuum pump system 10. In the embodiment, the housing 48 comprises five slices 50a, each housing a pump stage 12, preferably the pump stage 12 as shown in Fig.

[0049] 1. Furthermore, the housing 48 has a facility space, particularly a facility slice 50b.

[0050] The facility slice 50b houses a pump control system 52, preferably comprising a controller to control the pump stages 12, particularly the pumps 20, 22, 24 of the pump stages 12, and / or electronics for the vacuum pump system 10.

[0051] Further, an exhaust pump 30 is arranged inside the facility slice 50b. The exhaust pump 30 is connected via a manifold 28 to the outlets 26 of the pump stages 12. A bypass comprising a valve 36 is also connected to manifold 28 to selectively bypass the fluid stream past the exhaust pump 30. The exhaust pump 30 and / or the bypass 36 is preferably implemented, particularly arranged and / or connected, like the exhaust pump of Fig. 1.

[0052] The inlets 14 of the pump stages 12 are connected to a recipient 102, particularly a vacuum chamber, for example a EUV vacuum chamber or a desorption chamber of a DAC system, preferably via a manifold 16 connected to the inlets 14 of all pump stages 12 and to the recipient 102. As shown in Figure 2, the components, preferably all components of the vacuum pump system 10 are arranged inside a housing 48, preferably a single housing 48 of the vacuum pump system 10. Particularly, at least the pump stages 12 and the exhaust pump 30 are arranged inside the housing 48. Furthermore, it is preferred that one or more of the following is arranged inside the housing: the bypass 36; the manifold 28; the inlet manifold 16; a control for the exhaust pump 30 and / or the bypass 36 (see Fig. 1); sensors 42, 44, 46 (see Fig. 1); and a pump control system 52.

Claims

CLAIMS1. A vacuum pump system (10), comprisinga plurality of serially connected pump stages (12) arranged in parallel, wherein an inlet (14) of each pump stage (12) of the plurality of pump stages (12) is connectable to a recipient (102); andan exhaust pump (30), wherein an outlet (26) of each pump stage (12) of the plurality of pump stages (12) is connected via a manifold (28) to an inlet (32) of the exhaust pump (30).

2. The vacuum pump system according to claim 1, wherein the exhaust pump (30) is a dry pump, particularly a multistage roots pump.

3. The vacuum pump system according to claim 1 or 2, wherein the exhaust pump (30) is a condenser pump, particularly a liquid ring pump.

4. The vacuum pump system according to any one of claims 1-3, wherein the vacuum pump system (10) comprises a housing (48), wherein the pump stages (12) and the exhaust pump (30) are arranged inside the housing (48).

5. The vacuum pump system according to claim 4, wherein the housing (48) comprises a facility space, wherein a pump control system (52), is arranged inside the facility space, and wherein the exhaust pump (30) is arranged inside the facility space.

6. The vacuum pump system according to any one of claims 1-5, wherein the vacuum pump system (10) comprises a controller (40) to control the fluid flow through and / or past the exhaust pump (30).

7. The vacuum pump system according to claim 6, wherein the vacuum pump system (10) comprises a bypass (36) connected to the manifold (28) to selectively bypass (36) the exhaust pump (30) controlled by the controller (40).

8. The vacuum pump system according to claim 6 or 7, wherein the controller (40) is adapted to control the exhaust pump (30), particularly a speed of the exhaust pump (30).

9. The vacuum pump system according to any one of claims 6-8, wherein the controller (40) is adapted to control fluid flow via the exhaust pump (30) based on at least one of the following parameters: a fluid flow rate of the pump stages (12), a pressure in the manifold (28), a pressure at an outlet (34) of the exhaust pump (30), or an identification of the pumped fluid, particularly of H2.

10. The vacuum pump system according to any one of claims 1-9, wherein each pump stage (12) of the plurality of pump stages (12) comprises a primary booster pump (20), particularly a mechanical booster pump.

11. The vacuum pump system according to any one of claims 1-10, wherein each pump stage (12) of the plurality of pump stages (12) is a multistage pump stage comprising a plurality of pumps arranged in series.

12. The vacuum pump system according to any one of claims 1-11, wherein each pump stage (12) of the plurality of pump stages (12) comprises a secondary booster pump (22).

13. The vacuum pump system according to any one of claims 1-12, wherein each pump stage (12) of the plurality of pump stages (12) comprises a backing pump (24), particularly a multistage dry pump.

14. A vacuum system (100), particularly an extreme ultraviolet lithography system or a direct-air capture system, comprisinga chamber, preferably an extreme ultraviolet lithography vacuum chamber or a desorption chamber of a direct-air capture system, anda vacuum pump system according to any one of claims 1-13 connected to the chamber.

15. A method for generating a vacuum using a vacuum pump system according to any one of claims 1-13 or a vacuum system (100) according to claim 14.

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