Residue receiver, rotating target extreme ultraviolet radiation generation system, and method

Abstract

A residue receiver, a rotating target extreme ultraviolet radiation generating system, and a method of generating extreme ultraviolet radiation are provided. The residue receiver includes a concave surface configured to face a target material of the rotating target extreme ultraviolet radiation generating system. The rotating target extreme ultraviolet radiation generating system includes a chamber, a crucible, and a receiver. The method of generating extreme ultraviolet radiation includes rotating the crucible, irradiating the target material to generate a plasma that emits extreme ultraviolet radiation, and directing residue formed with the plasma using the receiver. A method of inspecting a photomask includes directing extreme ultraviolet radiation to the photomask, capturing one or more images of patterned radiation reflected from the photomask, and processing the one or more images. A method of manufacturing a semiconductor device includes directing extreme ultraviolet radiation to a photomask, exposing a photoresist layer to patterned radiation reflected from the photomask, developing the photoresist layer, and etching a substrate using the developed photoresist layer as a mask.

Description

Technical Field

[0001] This invention relates to a residue receiver, a rotating target ultraviolet radiation generation system, and a method. Background Technology

[0002] In semiconductor device manufacturing, extreme ultraviolet (EUV) radiation is used for photolithography and mask inspection processes. EUV radiation is generated by irradiating a target material (such as liquid tin) with a laser to form a plasma that emits EUV radiation. The structure and conditions of the EUV radiation generation system can affect the stability and integrity of the generated radiation. Degraded EUV radiation can adversely affect the photolithography and inspection processes that use it. Summary of the Invention

[0003] Embodiments of the present invention provide a residue receiver including a concave surface configured to face a target material of a rotating target extreme ultraviolet (EUV) laser generating system, wherein the concave surface exhibits a water contact angle (θ') greater than 85°.

[0004] Embodiments of the present invention provide a rotating target extreme ultraviolet (EUV) laser generating system, including a container forming a chamber; a crucible disposed in the chamber, the crucible including a cavity and an outer wall surrounding the cavity, and the crucible being configured to rotate about an axis about the center of the cavity; a receiver disposed above the cavity of the crucible, the receiver including a concave surface facing a portion of the inner surface of the outer wall of the crucible; a frame suspending the receiver above the crucible; a shield disposed above the frame; and a gasket including a thermally conductive material disposed in the gap between the frame and the shield.

[0005] Embodiments of the present invention provide a method for generating extreme ultraviolet (EUV) radiation, comprising rotating a crucible including an inner surface holding a target material, wherein the crucible is disposed inside a container; irradiating the target material with a laser to generate plasma emitting EUV radiation; and guiding residues formed during plasma generation with a receiver disposed above the crucible, wherein the receiver includes a concave surface facing the target material and the concave surface exhibits a water contact angle (θ') greater than 85°. Attached Figure Description

[0006] This disclosure is best understood from the detailed description below when read in conjunction with the accompanying drawings. It should be noted that, in accordance with industry standard practice, the various features are not drawn to scale and are for illustrative purposes only. In fact, the dimensions of the various features may be increased or decreased arbitrarily for clarity of discussion.

[0007] Figure 1A This is a schematic perspective view of a curtain detection tool conforming to some embodiments.

[0008] Figure 1B This is a schematic perspective view of a lithography system conforming to some embodiments.

[0009] Figure 2 This is a schematic cross-sectional view of components of a rotating target EUV radiation generation system conforming to some embodiments.

[0010] Figure 3 This is a schematic perspective view of a crucible conforming to some embodiments.

[0011] Figure 4 This is a schematic plan view of the receiver and crucible portions according to some embodiments.

[0012] Figure 5 This is a schematic cross-sectional view of the receiver and crucible portions according to some embodiments.

[0013] Figure 6 This is a schematic cross-sectional view of the receiver and crucible portions according to some embodiments.

[0014] Figure 7 This is a schematic cross-sectional view of the structural interface between the crucible, gasket, shield, and frame, conforming to some embodiments.

[0015] Figure 8 This is a schematic plan view of a gasket conforming to some embodiments.

[0016] Figure 9 This is a schematic cross-sectional view of a gasket portion conforming to some embodiments.

[0017] Figure 10 This is a schematic cross-sectional view of a gasket portion conforming to some embodiments.

[0018] Figure 11 This is a schematic cross-sectional view of the receiver portion according to some embodiments.

[0019] Figure 12 It conforms to some embodiments Figure 11 A schematic cross-sectional view of the receiver end shown.

[0020] Figure 13 This is a schematic cross-sectional view showing the water contact angle between a water droplet and a receiver material, according to some embodiments.

[0021] Figure 14 This is a schematic cross-sectional view of the receiver and crucible portions according to some embodiments.

[0022] Figure 15 This is a schematic diagram of a calculator system conforming to some embodiments.

[0023] Figure 16 This is a flowchart of a method for generating extreme ultraviolet radiation according to some embodiments.

[0024] Figure 17This is a flowchart of a photomask inspection method according to some embodiments.

[0025] Figure 18 This is a flowchart of a method for manufacturing a semiconductor device according to some embodiments. Detailed Implementation

[0026] The following disclosure provides numerous different embodiments or instances for implementing various features of the invention. Specific examples of components and configurations are described below to simplify the disclosure. These examples 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 in direct contact, and may also include embodiments where additional features may be formed between the first and second features so that the first and second features are not in direct contact. Furthermore, reference numerals and / or letters may be repeated throughout the disclosure. This repetition is for brevity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0027] Furthermore, for ease of explanation, spatially relative terms such as "beneath," "below," "lower," "above," "upper," and similar expressions may be used herein to describe the relationship between one component or feature shown in the figures and another component or feature. These spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to those shown in the figures. The device may have other orientations (rotated 90 degrees or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly. Furthermore, the term "made of" may mean "comprising" or "consisting of." In this disclosure, "one of A, B, C" refers to A, B, and / or C (A, B, C, A and B, A and C, B and C, or A, B, and C), and does not imply that one comes from A, one from B, and one from C, unless otherwise stated.

[0028] This disclosure relates to improving the stability and integrity of EUV radiation provided by rotating target extreme ultraviolet (EUV) radiation generation systems. Such EUV radiation generation systems can be used for mask inspection and lithography. The structure, materials, and operation of rotating target EUV radiation generation systems can play a role in ensuring optimal performance and lifespan of the rotating target EUV radiation generation system, as well as the optimal performance of associated inspection and lithography processes. Structural components, materials, and processes associated with rotating target EUV radiation generation systems can affect the stable generation of EUV radiation.

[0029] Inspection and lithography tools include optical components, which may include one or more components that reflect, transmit, and / or manipulate incident light. Examples of such optical components include one or more lenses, windows, filters, wedges, prisms, prism gratings, gratings, transmission fibers, etalons, diffusers, homogenizers, detectors, apertures, conical mirrors, mirrors, specular reflectors, and diffuse reflectors. One or more optical components may be used for one or more specific wavelength ranges, such as EUV output light wavelengths, radiation laser wavelengths, wavelengths suitable for measurement, or any other specific wavelength.

[0030] Here, the terms shielding, photomask, and photomask are used interchangeably. Shielding can be a reflective shielding used in connection with an EUV lithography system. Such reflective shielding can also be detected using EUV radiation. One embodiment of shielding includes a substrate formed of a suitable material, such as a low thermal expansion material or fused silica. In some embodiments, the substrate includes titanium dioxide (TiO2)-doped silicon dioxide (SiO2), or other suitable materials with low thermal expansion. In some embodiments, shielding includes multiple reflective layers (MLs) deposited on the substrate. In some embodiments, the multilayer includes multiple film pairs, such as molybdenum-silicon (Mo / Si) film pairs (e.g., a layer of molybdenum on or under a layer of silicon in each film pair). In some embodiments, alternatively, the multilayer includes a molybdenum-beryllium (Mo / Be) film pair, or other suitable materials configured to reflect EUV light. In some embodiments, shielding further includes a capping layer, such as ruthenium (Ru), disposed on the ML for protection. In some embodiments, shielding further includes an absorbing layer, such as a boron tantalum nitride (TaBN) layer, deposited on the multilayer. In some embodiments, the absorbing layer is patterned to define a layer of a semiconductor device. Alternatively, another reflective layer is deposited on a multilayer and patterned to define a layer of the semiconductor device, thereby forming an EUV phase-shift shield.

[0031] A lithography system or mask inspection system may include a light projection system configured to direct radiation to a mask. Depending on the nature of the mask and the lithography process, the radiation may pass through or be reflected from the mask to form patterned light. In the lithography process, the patterned radiation may be directed to a photoresist layer to form a pattern therein. In the inspection process, the patterned radiation may be directed to a sensor to collect an image of the radiation. One or more optical components may reduce and focus the patterned light onto the photoresist layer or the sensor.

[0032] In some embodiments, EUV lithography is used to form structures in a semiconductor substrate and / or one or more layers formed on the semiconductor substrate. In some embodiments, the semiconductor substrate includes a semiconductor wafer, such as a silicon wafer or other types of wafers. In some embodiments, the semiconductor substrate is coated with a photoresist layer sensitive to EUV light. The EUV lithography system focuses a pattern of EUV radiation onto the photoresist layer to cause a reaction in the irradiated portions of the layer. In some embodiments, the photoresist includes one or more photosensitive materials, which may be positive or negative photoresist. After irradiating the photoresist layer, an opening pattern can be formed in the layer by developing the layer using a developer. Developing a positive photoresist can form openings in the irradiated portions of the layer. Conversely, developing a negative photoresist can form openings in the unirradiated portions of the layer. Whether the photoresist functions as a negative or positive photoresist may depend on one or more of the composition of the photoresist and the composition of the developer. After patterning is formed on or in one or more layers of the semiconductor substrate, the lithography system may repeat the lithography process to form additional structures, thereby forming a semiconductor device.

[0033] Mask inspection can be performed on the mask used in lithography processes to determine whether the mask contains defects after initial production, or whether it has been damaged or contaminated during handling and use in the lithography process. Defects, damage, and contamination can adversely affect the performance of lithography processes using the mask. In some embodiments, mask inspection for EUV lithography processes is performed by irradiating the mask with EUV radiation, causing the mask to reflect a pattern of radiation onto a sensor (e.g., a charge-coupled device (CCD)). The sensor can capture images of one or more patterned radiations. A computer system can be used to process the images and determine whether the mask has any defects, damage, or contamination.

[0034] While the various embodiments disclosed herein are described with respect to EUV light generating apparatus for mask inspection and lithography, other applications of the disclosed embodiments may include, but are not limited to, other systems that require EUV light, such as precision metrology systems.

[0035] Figure 1A This is a schematic diagram of an EUV hood detection system 10, which includes a rotating target EUV radiation generation system 100 and is configured to generate EUV light. Figure 1BThis is a schematic diagram of an EUV lithography system 15 including a rotating target EUV radiation generation system 100, configured to generate EUV light. In some embodiments, the rotating target EUV radiation generation system 100 utilizes laser-produced plasma (LPP) to generate EUV radiation. In some embodiments, the system 100 generates EUV light with wavelengths ranging from about 1 nanometer (nm) to about 100 nm, or with wavelengths concentrated at about 13.5 nm. Figure 1A and Figure 1B The system 100 is coupled to the exposure tool 300 via a coupling mechanism 220. The coupling mechanism 220 may include optical components configured to transfer EUV radiation from the rotating target EUV radiation generating system 100 to the exposure tool 300.

[0036] exist Figure 1A In the illustrated embodiment, the exposure tool 300 includes a plurality of reflective optical components 305, a stage 310, and a detection sensor 315. Figure 1B In the illustrated embodiment, the exposure tool 300 includes a plurality of reflective optical components 305, a stage 310, and a wafer stage 320. EUV radiation from the rotating target EUV radiation generating system 100 is guided within the exposure tool 300 by the reflective optical components 305. The EUV radiation is also guided to a mask 314 fixed to the stage 310. Figure 1A In the illustrated embodiment, optical component 305 guides the patterned radiation reflected from the dome onto sensor 315. Sensor 315 collects images of one or more patterned radiations. In some embodiments, calculator system 710 controls the generation of EUV radiation in rotating target EUV radiation generation system 100 and processes the images collected by sensor 315 to detect any defects, damage, or contamination on the dome.

[0037] exist Figure 1B In the illustrated embodiment, the EUV light pattern reflected by the mask 314 is guided by the optical component 305 to a photoresist layer 318 disposed on a wafer 316 supported on a wafer stage 320. The computer system 710 controls the rotating target EUV radiation generation system 100 to generate EUV radiation and controls the wafer positioning by controlling the wafer stage 320. After exposure, as described above, the photoresist layer 318 is developed to form an opening pattern within the layer. The patterned photoresist layer can be used as a shield in subsequent processes, such as wet or dry etching, to extend the pattern to one or more underlying layers.

[0038] Figure 2This is a schematic diagram of the components of a rotating target EUV radiation generating system 100 according to some embodiments. The EUV source container 102 includes a chamber 104 housing a crucible 106. Target material 108 is disposed on the inner surface 110 of the outer wall 111 of the crucible 106. The crucible 106 may be made of a metal, such as stainless steel or a steel alloy. In some embodiments, the crucible 106 is made of a metal different from the target material. In some embodiments, the crucible 106 rotates about an axis 113 in direction R1 during EUV radiation generation. The direction of rotation may be clockwise or counterclockwise. In some embodiments, a motor (not shown) is provided to rotate the crucible to 25,000 revolutions per minute (rpm). In some embodiments, the outer wall 111 is substantially circular in plan view. In some embodiments, the rotation of the crucible 106 is controlled by a calculator system 710. Figure 3 This is a perspective view of a crucible 106 according to one embodiment.

[0039] In some embodiments, the target material 108 is deposited in a continuous strip on the inner surface 110 of the outer wall 111. A receiver 112 is disposed in the chamber 104 and suspended above the crucible 106 to allow the crucible to rotate freely while the receiver remains stationary. In some embodiments, the receiver 112 is configured to collect residue 114 produced by irradiation of the target material 108 by the laser beam 116.

[0040] Laser beam 116 is emitted by laser generator 118. In various embodiments, the laser generator may include a laser diode, a solid-state laser such as a carbon dioxide (CO2) laser source, or a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser source. Laser generator 118 may be a substantially stationary laser and emits laser beam 116 to superheat a target material 108 disposed in crucible 106 while the crucible rotates at high speed. As the crucible rotates, the target material passes through the excitation region of the laser. In various embodiments, laser beam 116 is substantially continuous or pulsed.

[0041] In some embodiments, the target material includes tin (Sn), tin alloys such as eutectic alloys containing Sn and lithium (Li), or any other useful metal. In some embodiments, the target material is liquefied on the inner surface 110 of the outer wall 111 during operation of the EUV hood detection system 10. In some embodiments, the rotating target EUV radiation generating system includes a heater near the crucible 106 to maintain the target material in a liquid state. As the target material 108 on the outer wall 111 of the crucible rotates into the excitation region of the laser beam 116, energy from the laser beam vaporizes the target material into a high-temperature plasma 122 that emits EUV radiation 120.

[0042] EUV source container 102 includes a first channel 105 configured to allow a laser beam 116 to enter a chamber 104, and a second channel 107 configured to allow EUV radiation 120 to exit from the chamber 104. In some embodiments, the first channel 105 and the second channel 107 are respectively coupled to container 102 and communicate with chamber 104. In some embodiments, the first channel 105 is connected to a first opening 124 via receiver 112, and the second channel 107 is connected to a second opening 126 via receiver 112. In some embodiments, the first opening 124 allows the laser beam 116 to enter to irradiate target material 108, and the second opening 126 allows EUV radiation 120 to exit from the plasma generation region. In some embodiments, the second opening 126 of the receiver is configured near the first opening 124. In some embodiments, the receiver includes a single opening (not shown) that simultaneously allows the laser beam to enter and EUV radiation to exit. In some embodiments, chamber 104 is maintained in a vacuum state, such as a high-vacuum chamber state. In some embodiments, chamber 104 is circular or elliptical in plan view.

[0043] Figure 4 This is a schematic plan view of a portion of a rotating target EUV radiation generation system 100, showing a crucible 106 and a portion of a receiver 112, consistent with some embodiments. Plasma is generated at position L by irradiating the target material 108 with a laser beam 116, causing the plasma to emit EUV radiation 120. The generation of plasma also produces residues 114, such as ions, gases, atoms, and particles of the target material. In some embodiments, residues 114 undesirably accumulate on various components of the rotating target EUV radiation generation system 100, such as the receiver 112 and the crucible 106. In some embodiments, residues 114 interfere with the irradiation of the target material 108 by the laser beam 116 and cause fluctuations in the intensity of the generated EUV radiation. Residue accumulation can cause the laser beam to become out of focus on the target material. For example, when the laser spot size on the target material is set to a diameter of about 30 micrometers (µm), the amount of defocusing caused by residues on the crucible 106 may be about 3 µm, resulting in a laser spot size of 33 µm. As a result, the laser spot size increases, and if the laser power is not adjusted to compensate, the intensity of the generated EUV radiation may decrease. This fluctuation in EUV radiation consistency can cause problems when using radiation inspection screens or performing photolithography processes.

[0044] In some embodiments, receiver 112 is configured to collect residue 114. In some embodiments, receiver 112 is positioned close to target material 108 and crucible 106. In some embodiments, target material 108 is positioned between receiver 112 and crucible 106. In some embodiments, a plasma 122 generation location L is positioned between target material 108 and receiver 112. In some embodiments, receiver 112 captures residue 114 generated at location L. In some embodiments, receiver 112 is spaced apart from target material 108. In some embodiments, residue 114 collected by receiver 112 circulates in the portion of crucible 106 facing the receiver. In some embodiments, in a plan view, receiver 112 is positioned above at least a portion of target material 108. The structure of receiver 112 and associated components of the rotating target EUV radiation generation system 100 may be adjusted according to the configuration of target material 108 and crucible 106.

[0045] Figure 5 This is a cross-sectional view of a portion of receiver 112 and crucible 106 according to some embodiments. Receiver 112 includes a first opening 124 allowing laser beam 116 to enter and a second opening 126 allowing EUV radiation 120 to exit. EUV radiation 120 and residue 114 are generated by irradiating liquefied target material 140 within a target area 117 using laser beam 116. Receiver 112 includes a residue collection surface 128 having an arcuate or concave cross-section facing the target material 140. An end 130 of the residue collection surface 128 of receiver 112 forms a residue recovery 132 between the receiver and crucible 106. Residue 114 can fall from the end 130 of receiver 112 into the residue recovery 132, down to the bottom of crucible 106. In some embodiments, the sidewall 136 of crucible 106 and the residue collection surface 128 of receiver 112 form a hollow internal region 134 in which residue can circulate (circulation is schematically illustrated by dashed arrows). In some embodiments, the centrifugal force generated by the rotation of crucible 106 causes residue 114 to move from residue recovery 132 in the direction of the dashed arrow, bypassing the hollow internal region 134, toward outlet 138. In some embodiments, the centrifugal force causes residue 114 to return to target region 117 on the inner surface of sidewall 136, and the returned residue is irradiated by laser beam 116 to generate plasma and EUV radiation 120.

[0046] In some embodiments, receiver 112 is supported above crucible 106 by frame 142. In some embodiments, receiver 112 is disposed in an opening formed by frame 142. In some embodiments, frame 142 is supported by one or more support structures (not shown) of a chamber 104 receiving crucible 106. In some embodiments, frame 142 extends from one edge of sidewall 136 to an opposite edge (not shown) across the cavity of crucible 112. Frame 142 supports receiver 112 such that crucible 106 can rotate while receiver remains stationary. In some embodiments, shield 144 is disposed above receiver 112 and a portion of frame 142. In some embodiments, one or more gaskets 146, 148 are disposed in the gap between frame 142 and shield 144. In some embodiments, gaskets 146, 148 contact frame 142, receiver 112, and shield 144. In some embodiments, frame 142 and / or shield 144 extend from one peripheral edge of crucible 106 to an opposite peripheral edge (not shown).

[0047] Figure 6 A cross-sectional view schematically illustrates another embodiment of the structural engagement between frame 150, receiver 152, and shield 154. A gasket 156 is located in the space between shield 154 and frame 150. One peripheral edge of crucible 106 is shown below receiver 152. Frame 150 and gasket 156 have annular structures surrounding crucible 106. Frame 150 is positioned on support 151 of container 102. Shield 154 covers the cavity of crucible 106, and receiver 152 is supported within an opening of shield 154. Shield 154 extends from one peripheral edge of crucible 106 over the opposite peripheral edge (not shown) of the crucible.

[0048] Figure 7 A partial cross-sectional view schematically illustrates another alternative embodiment of the structural engagement between a frame 158 portion, a receiver 160 portion, and a shield 162 portion for suspending the receiver above the crucible. In some embodiments, a gasket 164 is disposed near the receiver 160 and in the gap between the shield 162 and the frame 158. The gasket 164 contacts the receiver 160, the frame 158, and the shield 162.

[0049] Figure 8 It schematically illustrates what can be used Figure 5 , Figure 6 and Figure 7 A plan view of the gasket 166 in the illustrated embodiment. The gasket 166 has an annular shape and an outer diameter of R. d In some embodiments, the outer diameter R dThe range is from about 150 mm to about 300 mm, from about 180 mm to about 250 mm, or from about 200 mm to about 220 mm. The gasket is not limited to a ring-shaped structure in the plan view and may include any useful structure, such as elliptical, rectangular, or any irregular structure conforming to one or more other components, such as a chamber, frame, receiver, and shield. The gasket may have any useful dimensions suitable for interfacing with one or more of the chamber, frame, receiver, and shield. Furthermore, as... Figure 5 As shown in the embodiments of gaskets 146 and 148, two or more gaskets with different sizes (e.g., diameters) can be used to mate with the frame, receiver, and shield.

[0050] Figure 9 and Figure 10 The cross-sections of gaskets 168 and 170 with different structural configurations according to some embodiments are schematically illustrated. Gaskets 168 and 170 may be annular structures or have any other useful structures. Figure 9 The gasket 168 shown includes a flat surface, while Figure 10 The gasket 170 shown includes three flat surfaces and a grooved surface 171. In some embodiments, the height (H) of the gaskets 168, 170 may range from about 0.2 mm to about 10 mm, from about 1 mm to about 8 mm, or from about 3 mm to about 6 mm. In some embodiments, the width (W) of the gaskets 168, 170 may range from about 1 mm to about 30 mm, from about 5 mm to about 20 mm, or from about 10 mm to about 15 mm. In some embodiments, the perimeter (C) of the gaskets 168, 170 may be 2πR. d Where π represents pi, R d This represents the outer diameter of the gasket. In some embodiments, the outer diameter R of gaskets 168 and 170 is... d Corresponding to Figure 8 In the embodiment shown, R d The scope of the discussion. In some embodiments, the groove depth (D) of the gasket 170 is greater than about 0.1 mm or ranges from about 0.2 mm to about 8 mm, or from about 1 mm to about 5 mm. In some embodiments, the groove spacing (P) of the gasket 170 ranges from about 1 mm to about 10 mm, or from about 3 mm to about 7 mm. In some embodiments, the groove width (G) of the gasket 170 is... W The range is from greater than about 0 mm to about 2 mm, or from about 1 mm to about 1.5 mm. In some embodiments, the trench has the following characteristics: Figure 10 The cross-sectional view shows a rectangular cross-sectional structure. In some embodiments, the trench has a circular (U-shaped) bottom (not shown) in the cross-sectional view.

[0051] In some embodiments, one or more gaskets are provided to improve thermal conductivity between one or more components of a rotating-target EUV radiation generation system, such as a frame, shield, receiver, and chamber. In some embodiments, the gaskets comprise one or more materials exhibiting high thermal conductivity and stability at high operating temperatures. The gaskets can enhance heat dissipation and conductivity between any two or more components, such as the frame, shield, receiver, and chamber, thereby improving temperature control of the EUV generation process within the chamber. In some embodiments, one or more gaskets help maintain the receiver temperature below 350 degrees Celsius. By improving thermal conductivity, one or more gaskets can improve heat dissipation from the area generating EUV radiation and reduce the operating temperature of the rotating-target EUV radiation generation system. In some embodiments, the gaskets are formed of one or more copper, aluminum, aluminum alloys, graphite, tungsten, molybdenum, and silicon carbide.

[0052] Figure 11 A schematic cross-sectional view illustrating a portion of a receiver 172 including end 174 according to some embodiments. Figure 12 Schematic illustration Figure 11 An enlarged view of the inner end 174 of circle 176. In some embodiments, such as Figure 5 and Figure 6 As shown, ends 130 and 153 face the bottom of the cavity of crucible 106. In some embodiments, the structure of end 174 of receiver 172 facilitates the liquefaction of target material residue 114. Figure 5 and Figure 6 The liquefied residue 114 circulates within the hollow internal regions 134 and 155, returning to the target region 117. In some embodiments, the end faces C1 and C2 of the end 174 form a V-shaped structure to facilitate rapid dripping of the liquid residue 114 from the receiver 112 to the target region 117. Figure 5 The residue shown is recycled in 132.

[0053] Figure 12The length (L) of the non-bent wall segment of the receiver end 174 shown ranges from about 20 mm to about 50 mm, about 25 mm to about 45 mm, or about 30 mm to about 40 mm in some embodiments. End faces C1 and C2 each form an angle theta (θ) with the centerline 177 of the non-bent wall segment of end 174. The angle theta (θ) ranges from about 40 degrees to about 50 degrees, about 43 degrees to about 47 degrees, or about 45 degrees in some embodiments. According to some embodiments, the lengths of end faces C1 and C2 each range from about 2 mm to about 10 mm, about 3 mm to about 8 mm, or about 4 mm to about 6 mm. In some embodiments, end faces C1 and C2 are of the same length, such that end faces C1 and C2 of end 174 are symmetrical. In some embodiments, the lengths of end faces C1 and C2 are different. In some embodiments, the thickness (T) of the non-bent wall segment of end 174 is less than the length (L) of the non-bent wall segment but greater than the lengths of end faces C1 and C2. In some embodiments, the ratio (T / C) of the thickness (T) to either the length (C) of end faces C1 and C2 is approximately the square root of two (√2). The structure and dimensions of the end 174 and the non-bent wall section provide improved circulation of liquid residue within the crucible, particularly in the region between the outer wall of the crucible and the arcuate or concave surface of the receiver. The shape, angle, and dimensions of the end, including the non-bent wall section, can be adjusted such that the V-shaped structure provided by the end face helps prevent residue accumulation and promotes rapid dripping of residue from the end.

[0054] In some embodiments, the residue collection surface of the receiver may include a material exhibiting high water contact angle wettability (hydrophobicity), allowing liquefied residues (e.g., liquid tin residues) to flow easily across the residue collection surface to residue recovery without accumulating in large quantities on the residue collection surface. The high water contact angle facilitates rapid removal of liquid residues from the receiver surface, preventing significant accumulation of target material residues and improving the recycling efficiency of residues within the area defined by the receiver and crucible. High recycling efficiency promotes the return of liquefied residues to the target area and the outlet of the area defined by the receiver and crucible. In some embodiments, the residue collection surface includes a coating of a material exhibiting high water contact angle (hydrophobicity). In some embodiments, the receiver is formed of a material exhibiting high water contact angle (hydrophobicity).

[0055] Figure 13A portion of the material 178 forming the receiver residue collection surface coating or the receiver itself is schematically illustrated. A water droplet 179 rests on the material 178 and exhibits a contact angle theta (θ'). In some embodiments, a high water contact angle (hydrophobicity) corresponds to the receiver material or the coating formed on the residue collection surface exhibiting a water contact angle theta (θ') greater than or equal to about 80°, greater than or equal to about 85°, or greater than or equal to about 90°. In some embodiments, the contact angle of a clean sample of the receiver material or the coating formed on the residue collection surface can be measured using a goniometer (e.g., the Ossila L2004A contact angle goniometer). Instructions for use of the Ossila L2004A are provided in the Contact Angle Goniometer User Manual (Manual Version 1.2.E, Ossila Limited, 2023), the entire text of which is incorporated herein by reference.

[0056] Tungsten, tungsten alloys, and tungsten compounds are useful in forming coatings on receiver residue collection surfaces or in forming receivers themselves because these materials exhibit high water contact angles (hydrophobicity). Tungsten, tungsten alloys, and tungsten compounds also have properties that reduce the accumulation of residues (such as tin droplets) on receiver surfaces. The high melting point and corrosion resistance exhibited by tungsten, tungsten alloys, and tungsten compounds also make these materials resistant to deformation and degradation under the high temperatures and oxidizing conditions of rotating target EUV radiation generation systems. Receivers or coatings applied to them can be formed from pure tungsten, tungsten alloys, or tungsten compounds (such as one or more tungsten nitride, tungsten carbide, tungsten disulfide, and tungsten oxide). Other materials exhibiting high water contact angles (hydrophobicity) and suitable for forming coatings on receivers or residue collection surfaces include one or more tantalum, iridium, ruthenium, osmium, and rhenium. Tantalum, iridium, ruthenium, osmium, and rhenium can also be used in combination with one or more tungsten, tungsten alloys, or tungsten compounds. The high surface energy and wettability of tungsten, tantalum, iridium, ruthenium, osmium, and rhenium make these materials suitable for applications that require not only high surface energy and wettability, but also thermal stability, corrosion resistance, and mechanical strength.

[0057] Figure 14 A cross-section of a receiver 180 disposed on a portion of a crucible 182 according to some embodiments is schematically illustrated. The receiver is supported by a frame 184. A shield 186 is disposed on the receiver 180, and gaskets 188 and 190 are disposed in the gap between the shield 186 and the frame 184. Gas is present in a hollow interior region 192 defined by the receiver 180 and the crucible 182. Gas can be introduced through inlet 194 and extracted through outlet 196. The gas may consist solely of hydrogen (H2), or a combination of hydrogen with one or more inert gases such as nitrogen (N2), argon (Ar), and helium (He). Upon heating, hydrogen forms hydrogen radicals (H2). Hydrogen radicals can reduce oxidation on the inner surfaces of the chamber (such as the surfaces of receiver 180 and crucible 182). Hydrogen radicals can mitigate oxidation by reacting with oxygen already present in the chamber, thereby reducing the amount of oxygen available for oxidation. Hydrogen radicals can also be used to maintain the hydrophobicity of components (such as coatings formed on the receiver or materials forming the receiver).

[0058] In some embodiments, the calculator system 710 may be programmed to operate one or more components of the EUV mask inspection system 10 or the EUV lithography system 15 to perform any of the methods provided in this disclosure. The calculator system 710 may include any one or more local computing devices, one or more controllers connected to the EUV mask inspection system 10 or the EUV lithography system 15, or a network of computing devices. In one embodiment, the calculator system 710 is programmed to operate, including controlling one or more of the rotating target EUV laser generation system 100, exposure tool 300, inspection sensor 315, or wafer stage 320. The calculator system 710 may also process one or more images captured by the inspection sensor 315 to determine whether the mask contains any defects, damage, or contamination. Figure 15 One embodiment of the calculator system 710 is described, which communicates with one or more of the rotating target EUV laser generation system 100, exposure tool 300, detection sensor 315, or wafer stage 320 via a wireless or wired network 740 to allow data exchange between them. In some embodiments, the calculator system 710 is implemented using hardware or a combination of software and hardware, and may be a dedicated server, integrated into another entity, or distributed across multiple entities, such as via a cloud or wired network.

[0059] The calculator system 710 includes a display 711, a processor 712, memory 713, an input / output interface 714, a network interface 715, and storage 716. Storage 716 stores an operating system 717, programs, or application programs 718, such as applications for controlling one or more of the rotating target EUV laser generation system 100, exposure tool 300, detection sensor 315, or wafer stage 320. Processor 712 may be a general-purpose microprocessor, microcontroller, or similar device. Storage 716 may be random access memory (RAM), flash memory, read-only memory (ROM), hard disk or optical disk, or any other suitable storage device for storing information and instructions executed by processor 712. Processor 712 and storage 716 may be supplemented or integrated by special-purpose logic circuitry.

[0060] Network interface 715 may include network adapters, such as Ethernet cards and modems. In some embodiments, input / output interface 714 is configured to connect to multiple devices, such as input devices and / or output devices. Examples of input devices include keyboards and pointing devices, such as mice or trackballs, through which a user can provide input to the calculator system 710. Examples of output devices include display devices, such as light-emitting diode (LED) or liquid crystal display (LCD) screens, for displaying information to the user.

[0061] Application 718 may include instructions, when executed by computer system 710 (or its processor 712), to cause computer system 710 (or its processor 712) to control one or more of rotating target EUV laser generation system 100, exposure tool 300, detection sensor 315 or wafer stage 320, and to perform other operations, methods and / or processes explicitly or implicitly described in this disclosure.

[0062] Data 719 may include parameter data for controlling operation, data received from the rotating target EUV laser generation system 100, exposure tool 300, detection sensor 315 and / or wafer stage 320 via input / output interface 714 or network interface 715, data for display on display 711, data transmitted to or from the rotating target EUV laser generation system 100, exposure tool 300, detection sensor 315 and / or wafer stage 320 via network 740, or data generated during operation of the calculator system 710.

[0063] Figure 16 This describes a process flow diagram illustrating a method for generating extreme ultraviolet (EUV) radiation according to some embodiments. The method includes operation P100, rotating a crucible comprising an inner surface holding a target material, wherein the crucible is disposed within a chamber. The method further includes operation P101, irradiating the target material with a laser to generate plasma emitting EUV radiation. The method further includes operation P102, guiding residues formed during plasma generation with a receiver disposed above the crucible. In some embodiments, the method further includes operation P103, introducing hydrogen gas into the chamber between the target material and the receiver during plasma generation.

[0064] Figure 17 This describes a method flowchart for inspecting a photomask according to some embodiments. The method includes operation P200 to generate extreme ultraviolet (EUV) radiation. In some embodiments, operation P200 is based on... Figure 16 Perform as shown. Figure 17The method further includes operation P201, directing EUV radiation to a photomask to reflect patterned radiation from the photomask. The method further includes operation P202, capturing one or more images of the patterned radiation using a sensor. The method further includes operation P203, processing one or more images to detect one or more defects, damage, or contamination on the photomask.

[0065] Figure 18 This diagram illustrates a method flowchart for manufacturing a semiconductor device according to some embodiments. The method includes operating P300 to generate extreme ultraviolet (EUV) radiation. In some embodiments, operating P300 according to... Figure 16 Perform as shown. Figure 18 The method further includes operation P301, directing EUV radiation to a photomask to reflect patterned radiation from the photomask. The method further includes operation P302, exposing a photoresist layer to the patterned radiation, wherein the photoresist layer is disposed on a substrate. The method further includes operation P303, developing the photoresist layer to form a patterned photoresist layer including openings, and operation P304, etching the substrate through the openings in the patterned photoresist layer to extend the openings into the substrate. In some embodiments, the substrate comprises multiple layers, and the etching extends the openings into at least one of the multiple layers.

[0066] This disclosure provides structures, materials, and methods for maintaining the stability of EUV radiation generated by a rotating target EUV laser generation system. By maintaining the stability of EUV radiation, the stability and integrity of related lithography and inspection processes can also be maintained.

[0067] According to one embodiment, the residue receiver includes a concave surface configured to face the target material of a rotating target extreme ultraviolet (EUV) laser generating system, wherein the concave surface exhibits a water contact angle (θ') greater than 85°. In one embodiment, the concave surface is covered with a coating exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the coating comprises tungsten. In one embodiment, the coating comprises a tungsten compound. In one embodiment, the residue receiver is formed of a material exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the material comprises tungsten. In one embodiment, the material comprises a tungsten compound. In one embodiment, the residue receiver further includes an end portion configured near the bottom of the crucible of the rotating target EUV laser generating system, wherein the end portion has opposing end faces forming a symmetrical V-shaped structure configured to face the bottom of the crucible.

[0068] According to another embodiment, a rotating-target extreme ultraviolet (EUV) laser generating system includes a container forming a chamber; a crucible disposed within the chamber, the crucible including a cavity and an outer wall surrounding the cavity, and the crucible configured to rotate about an axis at the center of the cavity; a receiver disposed above the crucible cavity, the receiver including a concave surface facing a portion of the inner surface of the outer wall of the crucible; a frame suspending the receiver above the crucible; a shield disposed above the frame; and a gasket including a thermally conductive material disposed in a gap between the frame and the shield. In one embodiment, the thermally conductive material includes copper. In one embodiment, the receiver is configured through an opening in the frame, the shield covers the side of the receiver opposite the crucible, and the gasket is disposed between the shield edge and the frame. In one embodiment, the gasket contacts the frame, the shield, and the receiver. In one embodiment, the gasket fills the gap formed by the frame, the shield, and the receiver. In one embodiment, the receiver is configured through an opening in the shield, and the gasket is disposed between the shield edge and the frame. In one embodiment, the gasket includes a grooved surface.

[0069] According to another embodiment, a method for generating extreme ultraviolet (EUV) radiation includes rotating a crucible comprising retaining an inner surface of a target material, wherein the crucible is disposed inside a container; irradiating the target material with a laser to generate plasma emitting EUV radiation; and guiding residues formed during plasma generation with a receiver disposed above the crucible. In one embodiment, the receiver includes a concave surface facing the target material, and the concave surface exhibits a water contact angle (θ') greater than 85°. In one embodiment, the concave surface is covered with a coating exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the receiver is formed of a material exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the concave surface comprises tungsten. In one embodiment, the method further includes introducing hydrogen gas into the container at a location between the target material and the receiver during plasma generation.

[0070] According to another embodiment, a method for inspecting a photomask includes generating extreme ultraviolet (EUV) radiation by: rotating a crucible comprising holding an inner surface of a target material; irradiating the target material with a laser to generate plasma emitting EUV radiation; and guiding residues formed during plasma generation with a receiver disposed above the crucible. In one embodiment, the receiver includes a concave surface facing the target material, and the concave surface exhibits a water contact angle (θ') greater than 85°. The method further includes guiding EUV radiation to the photomask to reflect patterned radiation from the photomask; capturing one or more images of the patterned radiation with a sensor; and processing one or more images to detect one or more defects, damage, or contamination on the photomask. In one embodiment, the concave surface is covered with a coating exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the receiver comprises a material exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the concave surface comprises tungsten.

[0071] According to another embodiment, a method of manufacturing a semiconductor device includes generating extreme ultraviolet (EUV) radiation by: rotating a crucible comprising an inner surface holding a target material; irradiating the target material with a laser to generate plasma emitting EUV radiation; and guiding residue formed during plasma generation with a receiver disposed above the crucible, wherein the receiver comprises a concave surface facing the target material and exhibiting a water contact angle (θ') greater than 85°. The method further includes guiding EUV radiation to a photomask to reflect patterned radiation from the photomask; exposing a photoresist layer to the patterned radiation, wherein the photoresist layer is disposed on a substrate; developing the photoresist layer to form a patterned photoresist layer including openings; and etching the substrate through the openings in the patterned photoresist layer to extend the openings into the substrate. In one embodiment, the concave surface is covered with a coating exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the receiver is formed of a material exhibiting a water contact angle (θ') greater than 85°. In one embodiment, the concave surface comprises tungsten. In one embodiment, the substrate comprises multiple layers, and the etching extends the openings into at least one of the multiple layers.

[0072] The foregoing has outlined the features of several embodiments or examples to enable 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 purposes and / or advantages as the embodiments or examples introduced herein. Those skilled in the art should also recognize that such equivalent constructions should not depart from the spirit and scope of this disclosure, and that various changes, substitutions, and modifications can be made to this document without departing from the spirit and scope of this disclosure.

Claims

1. A residue receiver, characterized in that, include: A concave surface, configured to face the target material of a rotating target ultraviolet radiation generation system, wherein the concave surface exhibits a water contact angle greater than 85°.

2. The residue receiver according to claim 1, characterized in that, The concave surface is covered with a coating that exhibits a water contact angle greater than 85°.

3. The residue receiver according to claim 2, characterized in that, The coating comprises tungsten.

4. The residue receiver according to claim 3, characterized in that, The coating comprises a tungsten compound.

5. The residue receiver according to claim 1, characterized in that, It also includes an end portion, configured to be located near the bottom of the crucible of the rotating target ultraviolet radiation generating system. The ends have opposing end faces forming a symmetrical V-shaped structure, configured to face the bottom of the crucible.

6. A rotating target ultraviolet radiation generation system, characterized in that, include: A container that forms a cavity; A crucible, disposed in the chamber, the crucible including a cavity and an outer wall surrounding the cavity, and the crucible configured to rotate about an axis around the center of the cavity; A receiver is disposed above the cavity of the crucible, the receiver including a concave surface facing a portion of the inner surface of the outer wall of the crucible; A frame suspends the receiver above the crucible; A shield is configured above the frame; as well as The gasket includes a thermally conductive material disposed in the gap between the frame and the shield.

7. The rotating target ultraviolet radiation generating system according to claim 6, characterized in that, The receiver is configured through an opening in the frame, the shield covers the side of the receiver opposite the crucible, and the gasket is configured between the edge of the shield and the frame.

8. The rotating target ultraviolet radiation generating system according to claim 6, characterized in that, The receiver is configured through an opening in the shield, and the gasket is configured between the edge of the shield and the frame.

9. A method for generating extreme ultraviolet radiation, characterized in that, include: A rotating crucible, including maintaining the inner surface of the target material, wherein the crucible is configured inside a container; The target material is irradiated with a laser to generate plasma that emits the extreme ultraviolet radiation; as well as The residue formed during the generation of the plasma is guided by a receiver positioned above the crucible, wherein the receiver includes a concave surface facing the target material and the concave surface exhibits a water contact angle greater than 85°.

10. The method according to claim 9, characterized in that, It also includes introducing hydrogen into the container to a location between the target material and the receiver during plasma generation.

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