Lithography system and method thereof

Abstract

A method includes: forming a mask layer on a semiconductor wafer; generating light by tin droplets in a lithography system; exposing the mask layer by light; cleaning tin debris accumulated in the lithography system using hydrogen; delivering hydrogen from the lithography system to a fuel cell; and generating electricity by the fuel cell.

Description

Technical Field

[0001] This disclosure relates to lithography systems and methods. Prior Technology

[0002] The semiconductor integrated circuit industry has experienced exponential growth. Technological leadership in integrated circuit materials and design has led to the production of many generations of integrated circuits, each generation featuring smaller and more complex circuitry than the previous one. In the evolution of integrated circuits, functional density (the number of interconnecting elements on a given chip area) typically increases while geometry (the smallest component (or line) that can be created using manufacturing processes) decreases. This miniaturization usually benefits production efficiency and reduces associated costs. However, this miniaturization also increases the complexity of manufacturing processes and the overall manufacturing of integrated circuits. Summary of the Invention

[0003] According to at least one embodiment of the present disclosure, a method of a lithography system includes: forming a mask layer on a semiconductor wafer; generating light by means of a droplet of tin in a lithography exposure system; exposing the mask layer by means of the light; cleaning tin debris accumulated in the lithography exposure system by means of hydrogen gas; pumping the hydrogen gas from the lithography exposure system to a fuel cell; and generating electricity by means of the fuel cell.

[0004] According to at least one embodiment of the present disclosure, a method of a lithography system includes: processing a semiconductor wafer by an extreme ultraviolet (EUV) scanner; cleaning the EUV scanner by a hydrogen gas; generating electricity by passing the hydrogen gas through a fuel cell; and providing the electricity back to the EUV scanner.

[0005] According to at least one embodiment of the present disclosure, a lithography system includes: an extreme ultraviolet (EUV) scanner operable to generate EUV light by bombarding a plurality of tin droplets with at least one laser pulse; a cleaning system operable in the EUV scanner to guide hydrogen gas to clean the EUV scanner; a pump operable to remove the hydrogen gas from the EUV scanner; a fuel cell, in operation: receiving the hydrogen gas from the pump; generating electricity from the hydrogen gas; and forming water from a first portion of the hydrogen gas; a scrubber, in operation, burning a second portion of the hydrogen gas; and a power supply system, in operation: receiving the electricity from the fuel cell; and supplying the electricity to the EUV scanner. Simple Explanation of the Diagram

[0006] When read with reference to the accompanying drawings, the following detailed description is the best way to understand the nature of this disclosure. Note that, in accordance with standard industry practice, the various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of explanation. [] Figures 1A and 1B are schematic diagrams of a partial lithography scanner according to embodiments of the present disclosure. Figures 2 through 6 are diagrams of various embodiments of systems including lithography devices and fuel cells according to various forms disclosed herein. Figure 7 is a flowchart of a method for manufacturing components according to various forms disclosed herein. Implementation

[0007] The following disclosure provides numerous different embodiments or examples for implementing various features of the provided object. Specific examples of components and configurations are described below to simplify this disclosure. Of course, these are merely examples and are not intended to be limiting. For instance, in the following description, the formation of a first feature above or on a second feature may include embodiments where the first and second features are formed in direct contact, and may also include embodiments where additional features may be formed between the first and second features such that the first and second features are not in direct contact. Furthermore, in various instances, references to numbers and / or letters may be repeated. This repetition is for simplicity and clarity and does not, in itself, define the relationship between the various embodiments and / or configurations discussed.

[0008] Additionally, for ease of description, spatial relative terms such as "beneath," "below," "lower," "above," and "upper," and similar terms, may be used herein to describe the relationship between one element or feature as illustrated in the figures and another. Besides the orientations depicted in the figures, these spatial relative terms are intended to also cover different orientations of elements in use or operation. Devices may be oriented in other ways (rotated 90 degrees or otherwise), and the spatial relative descriptors used herein may be interpreted accordingly.

[0009] Terms such as “about,” “approximately,” “substantially,” and similar terms may be used here to simplify the description. Those with ordinary knowledge in the field are capable of understanding and inferring the meaning of this term.

[0010] This disclosure generally relates to lithography equipment used in the manufacture of semiconductor devices, and more particularly to systems and methods incorporating fuel cells. The fuel cell can convert waste hydrogen from the lithography equipment into electricity. The method relates to improving the power efficiency of using extreme ultraviolet (EUV) lithography equipment.

[0011] For decades, lithography techniques used in the production of semiconductor devices have been extended by increasing the numerical aperture of the optical projection of exposure equipment. This allows the exposure equipment to operate at the same wavelengths as previous generations of systems. This extension continues to be developed for advanced lithography techniques such as extreme ultraviolet (EUV) lithography. EUV lithography is being developed as the technology of choice for high-volume manufacturing (HVM) at the 5nm node (and beyond), and is expected to continue following Mohr's Law for the next few years. Even with the excellent imaging and stacking capabilities of existing EUV scanners, device output and yield can still be adversely affected by other factors, such as molecular or particle contamination on the imaging surface. Furthermore, maintaining high reflectivity of the light source and mirrors throughout the scanner's lifespan is beneficial. From this perspective, the use of hydrogen is beneficial in preventing these problems caused by reactions with tin plasma. Large amounts of hydrogen are used during exposure and directly burned in the scrubber. Hydrogen is a byproduct of fossil fuels used in industrial manufacturing.

[0012] The disclosed embodiments provide a method for reusing hydrogen by generating electricity during the operation of an extreme ultraviolet (EUV) lithography system using fuel cells. Under the concepts of environmental, social, and corporate governance (ESG), the reuse of hydrogen in manufacturing reduces waste, a responsibility of companies in a globalized value system. Fuel cells are placed between pumps and scrubbers to reuse waste hydrogen to generate electricity, thus achieving green manufacturing. The structure incorporates multiple fuel cells and offers the benefits of easy maintenance and repair. The use of fuel cells can reduce energy per wafer (EPW), a measure of the amount of electricity consumed per wafer processed by the EUV lithography system. Fuel cells become increasingly advantageous as hydrogen usage increases (as can be expected for each new manufacturing node).

[0013] Figure 1A is an illustration and schematic diagram of the lithography system 10 (or apparatus) according to some embodiments. The lithography system 10 is described in detail to provide context for understanding the power supply system 222 that utilizes hydrogen (which can clean the light collector of the lithography system 10).

[0014] In some embodiments, the lithography system 10 is an extreme ultraviolet (EUV) lithography system designed to expose a photoresist layer using EUV light rays, and can be considered as such. The EUV lithography system 10 can also be considered as an EUV scanner or a lithography scanner. According to some embodiments, the lithography system 10 includes a light source 120, an illuminator 140, a photomask stage 16, a projection optics module 180 (or a projection optics box, POB)), and a substrate stage 24. Components of the lithography system 10 may be added to or removed from the system, and the disclosure should not be limited to this embodiment.

[0015] Light source 120 is configured to generate light rays with wavelengths between about 1 nm and about 30 nm (in certain embodiments). In a particular example, light source 120 generates extreme ultraviolet (EUV) light rays with a center wavelength of about or substantially 13.5 nm. Alternatively, light source 120 may also be considered as an EUV light ray source. However, it is worth noting that light source 120 should not be limited to emitting EUV light rays. Light source 120 can be used to perform any high-intensity photon emission (from excited target material).

[0016] In various embodiments, the illuminator 140 includes various refractive optical elements, such as a single lens or a lens system with multiple reflectors 100, such as multiple lenses (zone plates), or reflective optical elements (for extreme ultraviolet lithography systems), such as a single mirror or a mirror system with multiple mirrors, for guiding light from the light source 120 to the photomask stage 16, particularly the photomask 18 mounted on the photomask stage 16. In embodiments where the light source 120 produces light in the extreme ultraviolet wavelength range, reflective optical elements are used. In some embodiments, the illuminator 140 includes at least two reflectors, at least three reflectors, or more.

[0017] A stage 16 is configured to mount a photomask 18. In some embodiments, the stage 16 includes an electrostatic chuck (e-chuck) for mounting the photomask 18. An electrostatic chuck is advantageous because gas molecules absorb extreme ultraviolet (EUV) light rays, and it is operable in lithography systems for EUV patterning that maintain a vacuum environment to avoid EUV light loss. In this embodiment, the photomask 18 is a reflective photomask. An exemplary structure of the photomask 18 includes a substrate of a suitable material, such as a material with a low thermal expansion coefficient (LTEM) or fused silica. Among various examples, materials with a low thermal expansion coefficient include titanium dioxide-doped silicon dioxide or other suitable materials with a low thermal expansion coefficient. The photomask 18 includes a reflective multilayer film deposited on the substrate. The stage 16 is operable to move in two horizontal directions (such as the X-axis and Y-axis) to expose multiple different areas of the semiconductor wafer 22 to light in the pattern produced by the photomask 18. The semiconductor wafer 22 may have a mask layer 26 on it, which may be a photoresist layer that is sensitive to light (with a pattern of photomask 18).

[0018] A projection optics module 180 (or projection optics box) is configured to pattern an imaging mask 18 onto a semiconductor wafer 22, wherein the semiconductor wafer 22 is mounted on a substrate stage 24 of the lithography system 10. In some embodiments, the projection optics module 180 has refractive optical elements (such as those used in ultraviolet lithography systems) or reflective optical elements (such as those used in extreme ultraviolet lithography systems) in various embodiments. Light rays (carrying an image patterned on the mask) guided from the mask 18 are collected by the projection optics module 180. The illuminator 140 and the projection optics module 180 can be collectively considered as the optical module of the lithography system 10. In some embodiments, the projection optics module 180 includes at least six reflective optical elements.

[0019] In some embodiments, the semiconductor wafer 22 may be made of silicon or other semiconductor materials. Alternatively, or even further, the semiconductor wafer 22 may contain other elemental semiconductor materials, such as germanium (Ge). In some embodiments, the semiconductor wafer 22 is made of compound semiconductors, such as silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP). In some embodiments, the semiconductor wafer 22 is made of semiconductor alloys, such as silicon germanium (SiGe), silicon germanium carbide (SiGeC), gallium arsenide phosphide (GaAsP), or gallium indium phosphide (GaInP). In some other embodiments, the semiconductor wafer 22 may be a silicon-on-insulator (SOI) substrate or a germanium-on-insulator (GOI) substrate.

[0020] In addition, semiconductor wafer 22 can have various device components. Examples of device components formed in semiconductor wafer 22 include transistors (e.g., MOSFETs, CMOS, BJTs, high-voltage transistors, high-frequency transistors, p-channel and / or n-channel field-effect transistors (PFETs / NFETs), etc.), capacitors, inductors, diodes, and / or other applicable components. Various processes can be implemented to form device components, such as deposition, etching, fabrication, lithography, annealing, and / or other suitable processes. In some embodiments, semiconductor wafer 22 is covered with a photoresist layer sensitive to extreme ultraviolet light. The various components include those described above and are integrated together and operable to perform lithography processes.

[0021] The lithography system 10 may include other modules or may be integrated (or coupled) to other modules, such as a cleaning module or device or system (e.g., cleaning system 62) designed to provide hydrogen to the light source 120 and a tin supply system (designed to provide liquid tin to the light source 120). Hydrogen helps reduce contamination on the light source 120. The cleaning system 62 can clean the light collector of the light source 120, but is not limited thereto. For example, tin debris 82A may be located on various components of the lithography system 10, and the cleaning system 62 can spray hydrogen onto these components to remove the tin debris 82A. Further details of the light source 120 and the cleaning system 62 will be provided and referenced in Figure 1B.

[0022] According to some embodiments, in Figure 1B, the light source 120 is shown as a schematic diagram. In some embodiments, the light source 120 uses a dual-pulse laser-produced plasma (LPP) mechanism to generate plasma 88 and additionally generate extreme ultraviolet rays from the plasma. The light source 120 includes a droplet generator 30, a droplet reservoir 35, a laser generator 50, a laser-produced plasma collector 60, a monitoring element 70, and a controller 90. Some or all of the light source 120 discussed above can operate under vacuum. It is worth noting that components of the light source 120 may be added or removed and should not be limited to the embodiments.

[0023] A droplet generator 30 is configured to generate a plurality of droplets 82 (which may be elongated) of target material 80 to an excitation region. The excitation region is the location where at least one laser pulse 51 from laser generator 50 bombards the droplets 82, as shown in Figure 1B. In one embodiment, the target material 80 comprises tin (Sn). In one embodiment, the droplets 82 may be formed and elliptical. In one embodiment, the droplets 82 are generated at a rate of about 50 kHz and introduced into the excitation region of the light source 120 at a rate of about 70 meters per second. Other materials may also be used for the target material 80, such as liquid materials containing tin, like a eutectic alloy of tin, lithium, and xenon. The target material 80 in the droplet generator 30 may be a liquid phase.

[0024] Laser generator 50 is configured to generate at least one laser pulse that converts droplet 82 into plasma 88. In some embodiments, laser generator 50 is configured to generate laser pulse 51 to bright spot 52 to convert droplet 82 into plasma 88, thereby generating extreme ultraviolet rays 84. Laser pulse 51 is guided through window 55 (or lens) and irradiates droplet 82 at bright spot 52. Window 55 is formed in a portion of light collector 60 and is made of a suitable material that is substantially transparent to laser pulse 51. Droplet reservoir 35 receives and collects unused droplet 82 and / or material scattered from droplet 82 (bombarded by laser pulse 51). Some of the scattered material may be located on various components of lithography system 10, such as light collector 60 of light source 120 (which is closest to tin droplet 82 when bombarded by laser pulse 51).

[0025] Plasma emits extreme ultraviolet (EUV) rays 84 (which are collected by a light collector 60). The light collector 60 further reflects and focuses the EUV rays 84 through an exposure apparatus for use in a lithography process. In some embodiments, the light collector 60 has an optical axis 61 that is parallel to the Z-axis and perpendicular to the X-axis. The light collector 60 may comprise a single portion (as shown) or at least two portions offset from each other in the Z-axis direction.

[0026] The concentrator 60 may also include a tube wall 65 connected to a cleaning system 62 and a first pump 66 and a second pump 68. The cleaning system 62 may include one or more nozzles that spray high-pressure hydrogen gas toward the lithography system 10 (such as the concentrator 60) to remove tin debris 82A from the surface of the concentrator 60. Cleaning by the cleaning system 62 is highly beneficial for maintaining the mirror surface of the concentrator 60, as it can increase the output power of the light from the light source 120 and improve wafer yield.

[0027] In some embodiments, the first pump 66 and the second pump 68 include a scrubber configured to remove particles and / or gases from the light collector 60. The first pump 66 and the second pump 68 (which may be referred to collectively as "pumps 66, 68") are described in more detail herein. In some embodiments, the first pump 66 and the second pump 68 do not include a scrubber, and the scrubber is external to the first pump 66 and the second pump 68 and is fluidly circulated with the first pump 66 and the second pump 68 through one or more fuel cells, as will be illustrated in more detail in Figure 2 of the schematic diagram. The first pump 66 and the second pump 68 are operable to discharge hydrogen (e.g., waste hydrogen) from the lithography system 10 to the fuel cell.

[0028] In one embodiment, the laser generator 50 is a carbon dioxide (CO2) laser source. In some embodiments, the laser generator 50 is used to generate laser pulses 51 with a single wavelength. The laser pulses 51 pass through optical components used for focusing and determining the incident angle of the laser pulses 51. In some embodiments, the laser pulses 51 have a spot size between about 200 micrometers and 300 micrometers (e.g., 225 micrometers). The laser pulses 51 are generated with a specific drive power to achieve a wafer production target, such as a yield of 125 wafers per hour (WPH). For example, the laser pulses 51 are configured with a drive power of about 23 kW. In various embodiments, the drive power of the laser pulses 51 is at least 20 kW, such as 27 kW.

[0029] Monitoring element 70 is configured to monitor one or more conditions in light source 120 to generate data for controlling adjustable parameters of light source 120. In some embodiments, monitoring element 70 includes a measuring device 71 and an analyzer 73. When measuring device 71 is configured to monitor the conditions of droplet 82 (provided by droplet generator 30), measuring device 71 may include an image sensor (such as a charge-coupled device (CCD)), complementary metal-oxide-semiconductor (CMOS) sensor, or similar. Measuring device 71 generates a monitoring image, including an image or video of droplet 82, and transmits the monitoring image to analyzer 73. When measuring device 71 is configured to detect the energy or intensity of extreme ultraviolet radiation 84 (generated by droplet 82 in light source 120), measuring device 71 may include some energy sensors. Energy sensors can be any suitable sensor (capable of observing and measuring the energy of electromagnetic radiation in the ultraviolet region).

[0030] Analyzer 73 is configured to analyze the signal generated by measurement device 71 and output the detected signal to controller 90 based on the analysis results. For example, analyzer 73 includes an image analyzer. Analyzer 73 receives image-related data transmitted from measurement device 71 and performs an image analysis process on the image of droplet 82 in the excitation region. Subsequently, analyzer 73 transmits analysis-related data to controller 90. This analysis may include errors in the flow path or position.

[0031] In some embodiments, two or more measuring devices 71 are used to monitor different conditions of the light source 120. One is configured to monitor the conditions of the droplet 82 (supply by the droplet generator 30), while others are configured to detect the energy or intensity of extreme ultraviolet rays 84 (generated by the droplet 82 in the light source 120). In some embodiments, the measuring device 71 is a final focus module (FFM) and is located in the laser generator 50 to detect light reflected from the droplet 82.

[0032] Controller 90 is configured to control one or more of the light sources 120. In some embodiments, controller 90 is configured to drive droplet generator 30 to generate droplets 82. Additionally, controller 90 is configured to drive laser generator 50 to generate laser pulses 51. The generation of laser pulses 51 can be controlled by controller 90 to be related to the generation of droplets 82, thus allowing laser pulses 51 to sequentially bombard each droplet 82. Controller 90 can be configured to control the delivery of hydrogen and the exhaust of waste hydrogen via a first pump 66 and a second pump 68.

[0033] In some embodiments, the droplet generator 30 includes a reservoir 31 and a nozzle assembly 32. The reservoir 31 is configured to contain target material 80. In some embodiments, a gas line 41 is connected to the reservoir 31 to introduce pump gas (such as argon) from a gas source 40 into the reservoir 31. The pressure in the reservoir 31 can be controlled by regulating the gas flow in the gas line 41. For example, when gas is continuously supplied to the reservoir 31 through the gas line, the pressure in the reservoir 31 increases. As a result, the target material 80 in the reservoir 31 is forced out of the reservoir 31 in the form of droplets 82. The reservoir 31 receives target material 80 (e.g., liquid tin) from a target material supply system (which may include one or more low-pressure reservoirs and one or more high-pressure reservoirs).

[0034] Figure 2 is a schematic diagram of a system 20 that uses waste hydrogen gas from a photolithography system 10 to generate electricity according to various embodiments.

[0035] Figure 7 is a flowchart of process 1000 according to various embodiments. In some embodiments, process 1000 for forming elements includes operations (operations 1010, 1020, 1030, 1040, 1050, and 1060). Process 1000 will be further described according to one or more embodiments. It is worth noting that the operations of process 1000 can be rearranged or changed, and are still included in the scope of various styles. More notably, additional processes can be provided before (or during or after) process 1000, and other processes will only be briefly described herein. In some embodiments, process 1000 is implemented by system 20 (described in Figures 2 through 6). Embodiments are described and structural components (described in Figures 1A through 6) are referenced thereto, but process 1000 can be implemented by a system having one or more structural components, which may differ from the structural components of system 20.

[0036] In Figure 2, system 20 includes facility system 220, lithography system 10, first pump 66, second pump 68, fuel cell 200, and scrubber 210. The operation of system 20 is described and referred to together with operations 1010 to 1060 of process 1000 depicted in Figure 7.

[0037] Facility system 220 may include various equipment and / or subsystems that facilitate the fabrication of semiconductor wafers and / or integrated circuit dies. To maintain the extreme ultraviolet (EUV) scanner (projecting EUV light onto semiconductor wafers to pattern very small features, such as lithography system 10), the facility system may include one or more cleanrooms, wafer handling and / or automation systems, photomask equipment, metrology and inspection equipment, vacuum systems, photoresist material and handling systems, gas and chemical delivery systems, cooling and / or heat dissipation systems, power supply systems, wafer cleanup systems, and waste disposal systems. Cleanrooms have contamination control. Cleanrooms have temperature, humidity, and particle level control, which is beneficial for achieving the quality and reliability of semiconductor manufacturing. Wafer handling and / or automation systems may include mechanical systems for wafer handling, which is beneficial for moving wafers between different equipment and process stations within the cleanroom. Automated wafer carrier and transport systems, such as overhead transport (OHT), reduce human contact to prevent contamination. Photomask equipment is operated to produce extreme ultraviolet (EUV) photomasks (used for patterning semiconductor wafers). Photomask equipment may include photomask fabrication equipment, inspection equipment, and maintenance systems. Measurement and inspection equipment is beneficial for measuring and verifying feature dimensions and assessing the quality of the manufactured semiconductor wafers. Vacuum systems provide a vacuum environment, which is beneficial for EUV lithography (e.g., efficiency). Photoresist material handling and processing systems may include processing and fabrication equipment, which are beneficial for photosensitive photoresist materials (sensitive to EUV light) and for precise control during coating, baking, and developing steps. Gas and chemical delivery systems deliver gases and chemicals to various equipment and processes. Cooling and temperature control systems cool and / or de-heat many devices in semiconductor manufacturing (generating heat during operation) and are beneficial for maintaining stable operating temperatures. Other systems in the facility may include power supply systems, water purification systems, gas supply systems, and waste treatment systems.

[0038] In Figure 2, the lithography system 10 generates extreme ultraviolet (EUV) rays 84 from tin droplets 82, corresponding to operation 1010 in Figure 7. The EUV rays 84 can be used to perform semiconductor processes on wafers, corresponding to operation 1060 in Figure 7. During the generation of the EUV rays 84, the tin droplets 82 are bombarded by laser light, generating tin debris 82A (accumulated on the surface of the light collector 60).

[0039] Tin debris 82A can be cleaned by guiding hydrogen gas to the surface of the collector 60, corresponding to operation 1020 in Figure 7. Hydrogen gas is delivered or supplied from facility system 220 to lithography system 10 through one or more delivery lines 230 connecting facility system 220 and lithography system 10. For example, facility system 220 may include a hydrogen supply system comprising one or more tanks (for storing hydrogen) and one or more pumps (for delivering hydrogen gas to lithography system 10 through delivery lines 230).

[0040] When hydrogen is sprayed onto the photolithography system 10, one or more pumps (e.g., first pump 66 and second pump 68) draw waste hydrogen from the photolithography system 10 and deliver it to the fuel cell 200 through one or more delivery lines 240, corresponding to operation 1030 in Figure 7. The delivery lines allow fluid flow between the first pump 66 and second pump 68 and the fuel cell 200. In some embodiments, the fuel cell 200 comprises a plurality of fuel cells interconnected (e.g., in a stacked configuration). Fuel cell 300 and fuel cell block 500 are embodiments of the fuel cell 200 and will be described in more detail with reference to Figures 3 through 6.

[0041] Fuel cell 200 takes waste hydrogen and air as input and outputs electricity and hydrogen as output. That is, fuel cell 200 uses hydrogen to generate electricity, corresponding to operation 1040 in Figure 7. Hydrogen is supplied from lithography system 10 to fuel cell via first pump 66 and second pump 68 and delivery line 240. Oxygen-containing air is supplied to fuel cell via facility system 220 and delivery line 270. In some embodiments, compressed air is supplied from air compressor of facility system 220. Electricity is supplied to facility system 220 via one or more wires 260. In some embodiments, facility system 220 is the load of fuel cell 200. In some embodiments, electricity is supplied to energy storage device of facility system 220, such as a battery. In some embodiments, electricity is supplied to power supply system 222 of facility system 220.

[0042] The power supply system 222 of facility system 220 can perform various operations to integrate power into system 20, for example, for use in lithography system 10. When power is generated, it is beneficial to fully connect the power to the facility system's power distribution system. This integration may include configuring fuel cell 200 to connect to the facility system's power supply system and load the distribution system of facility system 220. For the generated power, it is beneficial for it to flow smoothly and safely into the power grid of facility system 220 without causing interference or overload. The power generated by fuel cell 200 is typically synchronized with the main power grid. This synchronization involves ensuring that the frequency, voltage, and phase of the power are precisely matched to the main power grid parameters. Control systems and algorithms can be used to synchronize the two power sources to operate in a coordinated manner, preventing phase mismatches or frequency differences that could cause interference or damage to sensitive equipment. After power from fuel cell 200 is integrated into the power system and synchronized with the main power grid, the power distribution can be managed more effectively. Power electronic components (such as inverters or converters) can efficiently control the flow of power. Power distribution can be dynamically adjusted to direct power to the equipment in system 20, improve energy use, and prevent overload in various areas. Advanced power management algorithms and control systems can be used to generate a stable and reliable power supply throughout system 20.

[0043] Power from the power supply system integrated into facility system 220 is supplied to lithography system 10, corresponding to operation 1050 in Figure 7. Before the waste hydrogen is burned in scrubber 210, electricity can be generated and fed back to power supply system 222 of facility system 220 by guiding the waste hydrogen through fuel cell 200, which can reduce the energy consumption per wafer caused by lithography system 10.

[0044] Scrubber 210 can be an incineration scrubber or a "combustion scrubber". Scrubber 210 receives fuel and water from facility system 220 via delivery lines 280 and 290, respectively. Fuel can be used in the combustion section of the scrubber, while water can be used in the cleaning section. That is, scrubber 210 receives excess hydrogen from fuel cell 200 via delivery line 250. Hydrogen can be sprayed into the chamber of scrubber 210 (heated by the burning fuel) or can be directly burned into the flame of scrubber 210 (formed by the burning fuel). Here, the hydrogen and any pollutants are incinerated directly by the flame or indirectly by heating in the chamber, and the decomposed pollutants are cleaned by water in scrubber 210. The cleaned waste is then released into the atmosphere via delivery line 295 (or exhaust port). By using fuel cell 200 to utilize some or all of the hydrogen to generate electricity, the amount of hydrogen burned (or wasted) in scrubber 210 is reduced, which reduces the overall energy consumption of the lithography system 10 used to manufacture the body circuitry chips, and reduces the consumption of fossil fuels (because of the reduced load on the main grid).

[0045] Figures 3 through 7 are schematic perspective views and diagrams of the fuel cell 300 and fuel cell block 500 according to various embodiments. Figure 3 is a perspective view of the fuel cell 300. Figure 4 is a schematic diagram based on section line IV-IV in Figure 3. Figure 5 is a perspective view of the fuel cell block 500 in a connected configuration. Figure 6 is another perspective view of the fuel cell block 500, depicting the cover of each fuel cell.

[0046] In Figures 3 and 4, the fuel cell 300 includes a housing 380, an anode electrode 360 ​​(or positive electrode), a cathode electrode 350 (or negative electrode), a membrane 390, a first plate 320, and a second plate 310. The anode electrode 360, cathode electrode 350 (or negative electrode), membrane 390, first plate 320, and second plate 310 are disposed within the housing 380. The housing 380 may have a handle 382 mounted thereon. The side walls of the housing 380 are omitted in Figure 3 so as not to obstruct the view of the internal structure of the fuel cell 300.

[0047] The first plate 320 may be a first bipolar plate or a flow field plate and is operable to distribute a first reactant gas (e.g., hydrogen) to the electrochemically active region of the fuel cell 300. The first plate 320 may be a conduit for the gas (in the fuel cell 300). The first plate 320 is adjacent to the anode electrode 360. The first plate 320 may include one or more channels or grooves on both sides thereof. The channels provide gas distribution, that is, hydrogen can thus flow to contact the electrochemical reaction region of the anode electrode 360. The channels are advantageous for the even distribution of hydrogen on the active surface of the adjacent membrane electrode assembly (MEA), which includes the anode electrode 360, the cathode electrode 350, and the membrane 390 between them. The first plate 320 may also be advantageous for providing connectivity between adjacent fuel cells 300 in the stack (see fuel cell block 500 as shown in Figure 5), so that excess hydrogen 352 can flow to the fuel cell subsequently below the fuel cell 300. An airtight seal can be formed between the fuel cells 300, which allows the reactant gas (e.g., hydrogen) to flow efficiently between the individual fuel cells 300.

[0048] The second plate 310 is similar to the first plate 320 in most respects, but it is located adjacent to the cathode electrode 350. The second plate 310 performs and distributes oxygen-containing air through it.

[0049] The anode electrode 360 ​​is located between the channel of the first plate 320 and the membrane 390. Hydrogen gas 340 can enter the channel of the first plate 320 and is then separated into protons 342 and electrons 370 by the anode electrode 360. In some embodiments, the anode electrode 360 ​​comprises platinum or palladium, which is beneficial for separating hydrogen molecules into protons 342 and electrons 370.

[0050] Membrane 390 can be a polymer electrolyte membrane or a proton exchange membrane (PEM), which contains an ion-conducting polymer (allowing protons 342 to pass through while blocking electrons 370). Membrane 390 can be or contains perfluorosulfonic acid (PFSA), polybenzimidazole (PBI), sulfonated polyether ketone (SPEK), sulfonated polyether ether ketone (SPEEK), or similar substances. The combination of the first plate 320, membrane 390, and second plate 310 can be considered as a membrane electrode assembly (MEA).

[0051] In some embodiments, the membrane electrode assembly includes additional layers, such as gas diffusion layers (GDLs). Each gas diffusion layer may be made of a carbon-based or carbon-containing material and has hydrophobic properties, which is beneficial for efficient gas delivery and prevents water accumulation on the anode electrode 360 ​​and cathode electrode 350. The overall structure of the membrane electrode assembly including the gas diffusion layers may be stacked and arranged in the following order (from anode to cathode): anode gas diffusion layer, anode electrode 360, polymer electrolyte membrane 390, cathode electrode 350, and cathode gas diffusion layer. On both sides of the membrane electrode assembly, the gas diffusion layers may be in direct contact with the opposing bipolar plates (e.g., the first plate 320 and the second plate 310). The gas diffusion layers serve as interfaces between the anode electrode 360 ​​and the cathode electrode 350 of the membrane electrode assembly and the bipolar plates, providing electrical contact and uniform distribution of reactant gases (hydrogen and oxygen) on the anode electrode 360 ​​and the cathode electrode 350. The gas diffusion layers also allow byproducts of the electrochemical reaction (such as water vapor) to exit the fuel cell 300.

[0052] The cathode electrode 350 of the fuel cell 300 is similar to the anode electrode 360 ​​in most respects in terms of material composition. The cathode electrode 350 is disposed between the membrane 390 and the second plate 310.

[0053] As depicted in the fuel cell system 400 of Figure 4, the cathode electrode 350 and the anode electrode 360 ​​are connected to either end of the load 410. The load 410 may be the power supply system 222 of the facility system 220. In some embodiments, the load 410 is a battery that can be charged by the current (or power) generated by the fuel cell 300.

[0054] When proton 342 leaves the anode electrode 360 ​​and enters the membrane 390, a potential difference is generated between the anode electrode 360 ​​and the cathode electrode 350. As a result, electron 370 flows from the anode electrode 360 ​​to the load 410 and then to the cathode electrode 350.

[0055] When proton 342 passes through membrane 390 and contacts cathode electrode 350, proton 342 can recombine with electron 370 at cathode electrode 350 to form hydrogen atoms. Then, the hydrogen atoms react with oxygen in the air (flowing through second plate 310) to form water 335. Water 335 and excess oxygen 330 are sprayed out from fuel cell 300.

[0056] Figures 5 and 6 are schematic perspective views of a fuel cell block 500 according to various embodiments. The fuel cell block 500 includes at least two fuel cells (fuel cell 300A and fuel cell 300B) arranged in a vertically stacked configuration. Fuel cells 300A and 300B are largely similar to fuel cells 200 and 300 (as depicted in the reference drawings of Figures 2 through 4). A housing 380 may include sidewalls, and conduits 520 are formed therein. Water 510 can pass through the conduits 520 to cool fuel cells 300A and 300B. The conduits 520 of fuel cells 300A and 300B are aligned so that water 510 can flow from fuel cell 300B to the next fuel cell 300A. The respective anode electrodes 360 and cathode electrodes 350 of fuel cells 300A and 300B are aligned and can be in direct contact with each other. In this way, the fuel cell block 500 can have a higher current drive capability compared to a single fuel cell 300. The fuel cell block 500 can be more than two fuel cells (such as fuel cell 300A and fuel cell 300B depicted in Figure 5).

[0057] In Figure 6, when fuel cells 300A and 300B of fuel cell block 500 need to be removed (e.g., for maintenance or repair purposes), fuel cells 300A and / or 300B can be easily removed and replaced with replacement fuel cells, thus allowing operation to continue without interruption. This ease of removal and replacement is due to the presence of conduits 520 and aligned anode electrodes 360 and cathode electrodes 350 within the stacked fuel cells 300A and 300B.

[0058] In some embodiments, each fuel cell 300A and fuel cell 300B includes a cover 530. The cover 530 may be flip-topped, which is advantageous for the safe, quick, and easy removal and replacement of (damaged or soon-to-be-maintained) fuel cells 300A and 300B. The flip-topped cover 530 is mechanically connected to the housing 380 with a bolt, nut, or similar means and can be opened for internal maintenance. The anode electrode 360 ​​and cathode electrode 350 (protruding from the flip-topped cover 530) are accessible to confirm whether the fuel cells 300A and 300B are properly interconnected to transfer current and generate electricity.

[0059] The embodiments offer some advantages. Fuel cells 200, 300, and / or fuel cell blocks 500, positioned between the lithography system 10 and the scrubber 210, use hydrogen discharged from the lithography system 10 to generate electricity, which can be used to reduce the energy consumed per wafer by the lithography system 10. Fuel cell block 500 comprises two or more stacked fuel cells (e.g., fuel cell 300A and fuel cell 300B), which benefits from quick and easy repair and maintenance, reducing the downtime of fuel cell block 500.

[0060] According to at least one embodiment of the present disclosure, a method includes: forming a mask layer on a semiconductor wafer; generating light by means of a droplet of tin in a lithography system; exposing the mask layer by means of the light; cleaning tin debris accumulated in the lithography system by means of hydrogen gas; pumping the hydrogen gas from the lithography system to a fuel cell; and generating electricity by means of the fuel cell.

[0061] In some embodiments, the method further includes: burning the hydrogen leaving the fuel cell by a scrubber.

[0062] In some embodiments, burning the hydrogen involves burning less hydrogen by the scrubber than is pumped from the lithography system.

[0063] In some embodiments, generating the power via the fuel cell includes generating the power via a fuel cell block comprising the fuel cell and at least one additional fuel cell in contact with the fuel cell.

[0064] In some embodiments, the fuel cell is also cooled by water.

[0065] In some embodiments, cooling includes passing the water through a plurality of conduits through a plurality of casings of each individual fuel cell and the at least one additional fuel cell.

[0066] In some embodiments, it also includes: charging a battery with the power.

[0067] In some embodiments, the method further includes: providing the power to the lithography exposure system.

[0068] According to at least one embodiment of the present disclosure, the method includes: processing a semiconductor wafer by an extreme ultraviolet (EUV) scanner; cleaning the EUV scanner by a hydrogen gas; generating electricity by passing the hydrogen gas through a fuel cell; and providing the electricity back to the EUV scanner.

[0069] In some embodiments, generating the electricity involves passing hydrogen through a fuel cell block, the fuel cell block containing a plurality of fuel cells, and the fuel cells containing the fuel cells.

[0070] In some embodiments, the replacement of one of the fuel cells is also included.

[0071] In some embodiments, the method further includes: forming water from a first portion of the hydrogen using the fuel cell block; and burning a second portion of the hydrogen using a scrubber.

[0072] In some embodiments, the fuel cell block is further cooled with water through a plurality of conduits in a housing of each of the fuel cells.

[0073] In some embodiments, providing the power includes: integrating the power with a main power system via a power supply system; and delivering a second power, comprising at least a portion of the power, to the extreme ultraviolet scanner via the power supply system.

[0074] According to at least one embodiment of the present disclosure, a system includes: an extreme ultraviolet (EUV) scanner operable to generate EUV light by bombarding a plurality of tin droplets with at least one laser pulse; a cleaning system operable in the EUV scanner to guide hydrogen gas to clean the EUV scanner; a pump operable to remove the hydrogen gas from the EUV scanner; a fuel cell, in operation: receiving the hydrogen gas from the pump; generating electricity from the hydrogen gas; and forming water from a first portion of the hydrogen gas; a scrubber, in operation, burning a second portion of the hydrogen gas; and a power supply system, in operation: receiving the electricity from the fuel cell; and supplying the electricity to the EUV scanner.

[0075] In some embodiments, a fuel cell block is also included, which contains the fuel cell and a second fuel cell in contact with the fuel cell.

[0076] In some embodiments, the fuel cell includes a first housing through which a plurality of first conduits pass; and the second fuel cell includes a second housing through which a plurality of second conduits pass, the second conduits being aligned with the first conduits.

[0077] In some embodiments, each of the first fuel cell and the second fuel cell includes a flip-up cover mounted on the respective first housing and the second housing.

[0078] In some embodiments, the power supply system includes a battery, and the fuel cell is operable to charge the battery with the power.

[0079] In some embodiments, the system also includes a facility system of the power supply system, which, in operation, provides hydrogen to the cleaning system; provides air to the fuel cell; and provides fuel and a second water to the scrubber.

[0080] The foregoing summary outlines the features of several embodiments, enabling those skilled in the art to better understand the nature of this disclosure. Those skilled in the art should understand that this disclosure can be readily used as a basis for designing or modifying other processes and structures to achieve the same purpose and / or attain the same advantages of the embodiments described herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of this disclosure, and that various changes, substitutions, and modifications can be made without departing from the spirit and scope of this disclosure.

[0081] 10: Microfilm Exposure System 16: Light Mask Stage 18: Light Mask 20: System 22: Semiconductor wafers 24: Substrate carrier 26: Masking layer 30: Droplet generator 31: Storage warehouse 32: Nozzle assembly 35: Droplet Reservoir 40: Gas source 41: Gas pipeline 50: Laser Generator 51: Laser Pulse 52: Highlights 55: Window 60:Light collector 61: Optical axis 62: Clean up the system 65: Pipe wall 66: Pump 68: Pump 70: Monitoring components 71: Measurement equipment 73: Analyzer 80: Target Material 82: Droplets 82A: Debris 84: Extreme ultraviolet rays 88: Plasma 90: Controller 100: Reflector 120: Light source 140:Illuminator 180: Projection Optical Module 200: Fuel Cell 210: Washer 220: Facility System 222: Power Supply System 230: Delivery pipeline 240: Delivery pipeline 250: Delivery pipeline 260: Electric wire 270: Delivery pipeline 280: Delivery pipeline 290: Delivery pipeline 295: Delivery pipeline 300: Fuel Cell 300A: Fuel Cell 300B: Fuel Cell 310: Second board 320: First board 330: Oxygen 335: Water 340: Hydrogen 342: Proton 350: Cathode electrode 352: Excess hydrogen gas 360: Anode electrode 370: Electronics 380: Outer shell 382:Handle 390: Membrane 400: Fuel Cell System 410: Load 500: Fuel Cell Cube 510: Water 520: Catheter 530: Cover 1000: Process 1010: Operation 1020: Operation 1030: Operation 1040: Operation 1050: Operation 1060: Operation e -: electron IV-IV: Cross-sectional line segment H2: Hydrogen H+: Proton O2: Oxygen H₂O: water

[0082] Domestic storage information (please note in order of storage institution, date, and number) none. Overseas storage information (please note in the order of storage country, institution, date, and number) none.

Claims

1. A method of using a lithography system, comprising: forming a mask layer on a semiconductor wafer; generating light by means of a droplet of tin in a lithography exposure system; exposing the mask layer by means of the light; cleaning tin debris accumulated in the lithography exposure system by means of hydrogen gas; pumping the hydrogen gas from the lithography exposure system to a fuel cell; and generating electricity by means of the fuel cell, wherein generating electricity by means of the fuel cell includes generating electricity by means of a fuel cell block, the fuel cell block including the fuel cell and at least one additional fuel cell in contact with the fuel cell.

2. The method as described in claim 1 further comprises: burning the hydrogen leaving the fuel cell by means of a scrubber.

3. The method as described in claim 1 further includes cooling the fuel cell with water.

4. The method as described in claim 3, wherein cooling comprises passing the water through a plurality of conduits through a plurality of casings of each of the individual fuel cells and the at least one additional fuel cell.

5. The method as described in claim 1 further comprises: providing the power to the lithography exposure system.

6. A method for a lithography system, comprising: processing a semiconductor wafer by an extreme ultraviolet (EUV) scanner; cleaning the EUV scanner with hydrogen gas; generating electricity by passing the hydrogen gas through a fuel cell, wherein generating the electricity includes passing the hydrogen gas through a fuel cell block comprising a plurality of fuel cells, the fuel cells comprising the fuel cells; and providing the electricity back to the EUV scanner.

7. The method as described in claim 6 further includes replacing one of the fuel cells.

8. A lithography system comprising: an extreme ultraviolet (EUV) scanner operable to generate EUV light by bombarding a plurality of tin droplets with at least one laser pulse; a cleaning system operable in the EUV scanner to guide hydrogen gas to clean the EUV scanner; a pump operable to remove the hydrogen gas from the EUV scanner; a fuel cell, in operation: receiving the hydrogen gas from the pump; generating electricity from the hydrogen gas; and forming water from a first portion of the hydrogen gas; a scrubber, in operation, burning a second portion of the hydrogen gas; and a power supply system, in operation: receiving the electricity from the fuel cell; and supplying the electricity to the EUV scanner.

9. The system as described in claim 8 further includes a fuel cell block containing the fuel cell and a second fuel cell in contact with the fuel cell.

10. The system as claimed in claim 8 further includes a facility system of the power supply system, which, in operation: supplies hydrogen to the cleaning system; supplies air to the fuel cell; and supplies fuel and a second water to the scrubber.

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