Efficient water-cooling EUV photoetching machine reflector

Abstract

The invention relates to the technical field of semiconductor photoetching, in particular to an efficient water-cooling EUV photoetching machine reflector which comprises a reflector body, a sealing plunger and a blocking plunger, a plurality of transverse hole channels and a plurality of longitudinal hole channels are formed in the reflector body, and the transverse hole channels and the longitudinal hole channels are communicated with each other and extend to the outside of the reflector body. The transverse hole channels and the longitudinal hole channels respectively form openings in the edges of the mirror body; the multiple sealing plungers are embedded in the openings, and at least two openings are reserved to serve as a water inlet and a water outlet; the multiple blocking plungers are embedded in the transverse hole channels and the longitudinal hole channels correspondingly so that continuous water cooling hole channels can be formed between the water inlet and the water outlet. Therefore, the high-efficiency and high-reliability cooling performance is achieved, the high-temperature influence of the high-power EUV light source on the photoetching machine reflector can be reduced, thermal deformation is avoided, and the working performance and long-term stability of the photoetching machine reflector are improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor lithography technology, and specifically provides a highly efficient water-cooled EUV lithography machine mirror. Background Art

[0002] In an EUV lithography machine, the mirror needs to achieve a high reflectivity (>90%) reflection near a wavelength of 13.5 nm, and the surface of the mirror is usually a Mo / Si multilayer film structure. Due to the extremely high power of the EUV light source, the mirror absorbs the residual heat of the EUV light source, resulting in the following problems: 1. Thermal deformation: The temperature gradient causes nanoscale deformation of the mirror surface, reducing the lithography resolution.

[0003] 2. Thermal stress: Uneven temperature distribution will generate thermal stress inside the mirror, which may cause damage to the mirror surface and affect the service life.

[0004] 3. Increased maintenance cost: Thermal deformation and thermal stress will accelerate the aging of the mirror, increase the replacement frequency, and higher maintenance requirements and shorter replacement cycles will drive up the operating cost. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a highly efficient water-cooled EUV lithography machine mirror, which has efficient and highly reliable cooling performance, can reduce the high-temperature influence of the high-power EUV light source on the lithography machine mirror, avoid thermal deformation, and improve the working performance and long-term stability of the lithography machine mirror.

[0006] A highly efficient water-cooled EUV lithography machine mirror provided by the present invention specifically includes a mirror body, a sealing plunger, and a blocking plunger. A plurality of transverse channels and a plurality of longitudinal channels are opened inside the mirror body. The transverse channels and the longitudinal channels communicate with each other and extend to the outside of the mirror body. The transverse channels and the longitudinal channels respectively form openings at the edge of the mirror body; a plurality of sealing plungers are embedded in the openings, and at least two openings are reserved as the water inlet and the water outlet; a plurality of blocking plungers are respectively embedded in the transverse channels and the longitudinal channels to form a continuous water-cooling channel between the water inlet and the water outlet.

[0007] Preferably, the main body of the sealing plunger is a cylinder; one end of the sealing plunger is provided with an intersecting first flow-stabilizing surface and a first inclined surface.

[0008] Preferably, the main body of the blocking plunger is a cylinder; both ends of the blocking plunger are provided with second flow-stabilizing surfaces, and both ends of the blocking plunger are also provided with second inclined surfaces, wherein the second flow-stabilizing surface and the second inclined surface at the same end intersect.

[0009] Preferably, the first inclined surfaces of adjacent sealing plungers are adapted to fit against each other so that the two first steady flow surfaces of adjacent sealing plungers are connected to form a continuous steady flow surface; the second inclined surface of the blocking plunger is adapted to fit against the first inclined surface of the sealing plunger so that the second steady flow surface of the blocking plunger is connected to the first steady flow surface of the sealing plunger to form a continuous steady flow surface.

[0010] Preferably, at least two lugs are further provided on the mirror body; the water inlet and the water outlet are respectively opened on the lugs.

[0011] Preferably, the cross-sections of the transverse channel and the longitudinal channel along the radial direction are circular; the centers of the transverse channel and the longitudinal channel along the axial direction are located within the neutral plane of the mirror body.

[0012] Preferably, the transverse channel and the longitudinal channel are formed by drilling.

[0013] Preferably, the sealing plunger is adhesively bonded to the transverse channel and the longitudinal channel; the blocking plunger is adhesively bonded to the transverse channel and the longitudinal channel.

[0014] Preferably, the material of the mirror body is microcrystalline glass; the linear expansion coefficient of the mirror body is ≤1×10 -6 / K.

[0015] Preferably, the sealing plunger and the blocking plunger are made of the same material.

[0016] Compared with the prior art, the present invention can achieve the following beneficial effects: (1) An efficient water-cooled EUV lithography machine mirror provided by the present invention has efficient and highly reliable cooling performance, can reduce the high-temperature influence of a high-power EUV light source on the lithography machine mirror, avoid thermal deformation, and improve the working performance and long-term stability of the lithography machine mirror.

[0017] (2) An efficient water-cooled EUV lithography machine mirror provided by the present invention can optimize and adjust the path of the water-cooling channel according to needs by setting the transverse channel, the longitudinal channel, the sealing plunger and the blocking plunger with adjustable positions and quantities, thereby improving the water-cooling and heat-dissipating efficiency of the efficient water-cooled EUV lithography machine mirror.

[0018] (3) An efficient water-cooled EUV lithography machine mirror provided by the present invention can effectively avoid the formation of fluid turbulence of the cooling water inside the water-cooling channel by setting the first steady flow surface and the second steady flow surface to be connected to form a continuous steady flow surface, and further avoid disturbing the mirror surface shape.

[0019] (4) An efficient water-cooled EUV lithography machine mirror provided by the present invention can reduce the influence of the temperature difference on the mirror surface shape by optimizing the shapes and materials of the transverse channel, the longitudinal channel, the sealing plunger and the blocking plunger. Brief Description of the Drawings

[0020] The accompanying drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a partial sectional structural schematic diagram of a highly efficient water-cooled EUV lithography machine mirror provided by an embodiment of the present invention; Figure 2 is a side view structural schematic diagram of a highly efficient water-cooled EUV lithography machine mirror provided by an embodiment of the present invention; Figure 3 is Figure 2 a schematic diagram of the A-A sectional structure of the highly efficient water-cooled EUV lithography machine mirror of the illustrated embodiment; Figure 4 is a schematic diagram of the working principle of a highly efficient water-cooled EUV lithography machine mirror provided by an embodiment of the present invention; Figure 5 is a side view structural schematic diagram of a mirror body provided by an embodiment of the present invention; Figure 6 is Figure 5 a schematic diagram of the B-B sectional structure of the mirror body of the illustrated embodiment; Figure 7 is a structural schematic diagram of a sealing plunger provided by an embodiment of the present invention; Figure 8 is a structural schematic diagram of a blocking plunger provided by an embodiment of the present invention; Figure 9 is Figure 8 a schematic diagram of the C-C sectional structure of the blocking plunger of the illustrated embodiment.

[0021] Among them, the reference numerals include: 1 mirror body, 11 transverse channels, 12 longitudinal channels, 13 openings, 14 lugs, 2 sealing plunger, 21 first steady flow surface, 22 first inclined surface, 3 blocking plunger, 31 second steady flow surface, 32 second inclined surface, 41 water inlet, 42 water outlet, 43 water-cooling channels. Detailed implementation manners

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention. Similar elements in different embodiments are labeled with related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present invention. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present invention are not shown or described in the specification, in order to avoid the core part of the present invention being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and the general technical knowledge in the art.

[0023] It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other to form various embodiments. At the same time, the steps or actions in the method description can also be adjusted in the order that is obvious to those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences, unless it is stated that a certain sequence must be followed.

[0024] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0025] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0026] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0027] As Figures 1 to 6 shown, an embodiment of the present invention provides a highly efficient water-cooled EUV lithography machine mirror, which is particularly suitable for a high-power laser plasma light source environment. Specifically, it includes a mirror body 1, a sealing plunger 2, and a blocking plunger 3. A plurality of transverse channels 11 and a plurality of longitudinal channels 12 are formed inside the mirror body 1. The transverse channels 11 and the longitudinal channels 12 communicate with each other and extend to the outside of the mirror body 1. The transverse channels 11 and the longitudinal channels 12 respectively form openings 13 at the edge of the mirror body 1. A plurality of sealing plungers 2 are embedded in the openings 13. Among them, at least two openings 13 are reserved as the water inlet 41 and the water outlet 42 for flowing in and out of the cooling water. A plurality of blocking plungers 3 are respectively embedded in the transverse channels 11 and the longitudinal channels 12 to form a continuous water-cooling channel 43 between the water inlet 41 and the water outlet 42. Thus, the highly efficient water-cooled EUV lithography machine mirror has highly efficient and highly reliable cooling performance, can reduce the high-temperature influence of the high-power EUV light source on the lithography machine mirror, avoid thermal deformation, and improve the working performance and long-term stability of the lithography machine mirror.

[0028] Specifically, the cooling water is driven by a cooling pump outside the mirror body 1 and flows into the inside of the mirror body 1 from the water inlet 41; then it passes through the water-cooling channel 43 formed by splicing a plurality of sealing plungers 2 and blocking plungers 3 respectively, turns and flows towards the water outlet 42; finally, it flows out of the mirror body 1 from the water outlet 42; thereby realizing the absorption and removal of the heat of the mirror by circulating the cooling water.

[0029] Among them, a plurality of transverse channels 11 and a plurality of longitudinal channels 12 are arranged inside the mirror body 1, and the positions and numbers of the plurality of sealing plungers 2 and the plurality of blocking plungers 3 can be set and adjusted arbitrarily, so as to realize the optimization and adjustment of the path of the water-cooling channel 43 according to needs, thereby improving the water-cooling and heat dissipation efficiency of the highly efficient water-cooled EUV lithography machine mirror.

[0030] Among them, there is no limitation on the specific installation positions and quantities of the transverse channels 11, longitudinal channels 12, sealing plungers 2, and blocking plungers 3 here. They can be arranged and combined arbitrarily according to needs, as long as a one-way continuous water-cooling channel 43 is formed between the water inlet 41 and the water outlet 42 for water-cooling the mirror body 1.

[0031] As Figure 7 shown, the main body of the sealing plunger 2 is a cylinder and can be matched with the transverse channel 11 and the longitudinal channel 12. After the sealing plunger 2 is installed on the mirror body 1, a first steady flow surface 21 and a first inclined surface 22 that intersect are provided at one end close to the water-cooling channel 43; the first steady flow surface 21 is used to form a continuous steady flow surface in the water-cooling channel 43.

[0032] As Figure 8 and Figure 9 shown, the main body of the blocking plunger 3 is a cylinder and can be matched with the transverse channel 11 and the longitudinal channel 12. Second steady flow surfaces 31 are provided at both ends of the blocking plunger 3, and second inclined surfaces 32 are also provided at both ends of the blocking plunger 3. Among them, the second steady flow surface 31 and the second inclined surface 32 located at the same end intersect; the second steady flow surface 31 is used to form a continuous steady flow surface in the water-cooling channel 43.

[0033] As Figure 3 and Figure 4 shown, when the sealing plunger 2 and the blocking plunger 3 are embedded inside the mirror body 1 to form the water-cooling channel 43, the following assembly methods may be adopted between the sealing plunger 2 and the blocking plunger 3: When two sealing plungers 2 are assembled adjacent to each other, the first inclined surfaces 22 of the adjacent sealing plungers 2 are adapted to fit each other so that the two first steady flow surfaces 21 of the adjacent sealing plungers are connected to form a continuous steady flow surface. When the sealing plunger 2 and the blocking plunger 3 are assembled adjacent to each other, the second inclined surface 32 of the blocking plunger 3 is adapted to fit the first inclined surface 22 of the sealing plunger 2 so that the second steady flow surface 31 of the blocking plunger is connected to the first steady flow surface 21 of the sealing plunger to form a continuous steady flow surface.

[0034] Specifically, by setting the first steady flow surface 21 and the second steady flow surface 31 to be connected at the turning point of the water-cooling channel 43 to form a continuous steady flow surface, when the cooling water passes through the first steady flow surface 21 and the second steady flow surface 31, the formation of fluid turbulence is effectively avoided, and further, the disturbance of the mirror surface shape caused by the flow of the cooling water inside the water-cooling channel 43 is avoided.

[0035] Preferably, the first steady flow surface 21 and the second steady flow surface 31 adopt the curved surface of an equal-diameter right-angle elbow pipe. Through curvature optimization, the flow velocity distribution is regulated, and further, fluid turbulence is suppressed to avoid disturbing the mirror surface shape.

[0036] As Figures 1 to 4As shown, at least two lugs 14 are further provided on the mirror body 1. The lugs 14 are used to mount the mirror body 1 to the mirror mounting bracket. Therefore, the lugs 14 usually form protrusions on the mirror body 1. The water inlet 41 and the water outlet 42 are respectively opened on the lugs 14, so that when the cooling water passes through the water cooling channel 43, the cooling water flows into the water cooling channel 43 from the water inlet 41 at the first lug 14 and flows out from the water outlet 42 at the second lug 14 through the water cooling channel 43. That is to say, the cooling water also participates in heat exchange at the lugs 14, thereby taking away part of the heat and reducing the influence of the mirror surface temperature difference on the mirror surface shape.

[0037] As Figure 1 , Figure 2 and Figure 5 shown, the cross-sections of the transverse channel 11 and the longitudinal channel 12 along the radial direction are circular, so that the transverse channel 11 can be matched with the sealing plunger 2 and the blocking plunger 3, and the longitudinal channel 12 can also be matched with the sealing plunger 2 and the blocking plunger 3. The centers of the transverse channel 11 and the longitudinal channel 12 along the axial direction are located in the neutral plane of the mirror body 1, avoiding the deformation of the mirror surface shape caused by inconsistent pressures on the front and back sides of the mirror.

[0038] In some possible embodiments, the transverse channel 11 and the longitudinal channel 12 are formed by drilling.

[0039] In some possible embodiments, the sealing plunger 2 is glued to the transverse channel 11 and the longitudinal channel 12, and the blocking plunger 3 is glued to the transverse channel 11 and the longitudinal channel 12, so as to ensure the sealing and blocking effects and avoid the leakage of cooling water.

[0040] In some possible embodiments, the material of the mirror body 1 is microcrystalline glass, and the linear expansion coefficient of the mirror body 1 ≤ 1×10 -6 / K, so that the mirror body 1 has high surface accuracy. Specifically, the surface accuracy (RMS) of the mirror is maintained at ≤ 0.1 nm.

[0041] In some possible embodiments, the materials of the sealing plunger 2 and the blocking plunger 3 are the same, and the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 match the linear expansion coefficient of the mirror body 1, thereby reducing the influence of the mirror surface temperature difference on the mirror surface shape.

[0042] Specifically, in actual applications, since the linear expansion coefficients of the sealing plunger 2, the blocking plunger 3 and the mirror body 1 cannot be exactly the same, when the difference between the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 and the linear expansion coefficient of the mirror body 1 is within the allowable range, it is considered that the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 match the linear expansion coefficient of the mirror body 1.

[0043] Preferably, the difference between the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 and the linear expansion coefficient of the mirror body 1 is less than 1×10E-7 At / K, it is considered that the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 match the linear expansion coefficient of the mirror body 1.

[0044] Embodiment: As Figures 1 to 6 shown, an embodiment of the present invention provides a highly efficient water-cooled EUV lithography machine mirror, specifically including a mirror body 1, 10 sealing plungers 2 and 3 blocking plungers 3. The material of the mirror body 1 is microcrystalline glass with a linear expansion coefficient ≤ 1×10 -6 / K, so that the surface shape accuracy of the mirror body 1 is maintained at ≤ 0.1 nm. Two horizontal channels 11 are drilled horizontally inside the mirror body 1, and four vertical channels 12 are drilled vertically. The horizontal channels 11 and the vertical channels 12 communicate with each other and extend to the outside of the mirror body 1 to form a total of 12 openings 13. The mirror body 1 is also provided with three protruding lugs 14, and the horizontal channel 11 at the bottom penetrates through the two lugs 14 at the bottom.

[0045] As Figures 3 to 4 shown, the openings 13 passing through the two lugs 14 at the bottom are reserved and used as the water inlet 41 and the water outlet 42 respectively. The 10 sealing plungers 2 are sequentially embedded in the remaining openings 13 and connected by gluing; the 3 blocking plungers 3 are sequentially embedded in the two horizontal channels 11 according to the Figure 3 shown positions, so that a continuous water-cooling channel 43 is formed between the water inlet 41 and the water outlet 42.

[0046] As Figures 1 to 6 shown, the cross-section of the horizontal channel 11 and the vertical channel 12 along the radial direction is circular, and the center along the axial direction is located in the neutral plane of the mirror body 1. The main bodies of the sealing plunger 2 and the blocking plunger 3 are cylinders. One end of the sealing plunger 2 is provided with an intersecting first flow-stabilizing surface 21 and a first inclined surface 22, and both ends of the blocking plunger 3 are provided with intersecting second flow-stabilizing surfaces 31 and second inclined surfaces 32.

[0047] Among them, the first inclined surfaces 22 of adjacent sealing plungers 2 are mutually attached, so that the two first flow-stabilizing surfaces 21 are connected to form a continuous flow-stabilizing surface; the second inclined surface 32 of the blocking plunger 3 is attached to the first inclined surface 22 of the adjacent sealing plunger 2, so that the second flow-stabilizing surface 31 is connected to the first flow-stabilizing surface 21 to form a continuous flow-stabilizing surface.

[0048] In addition, the sealing plunger 2 and the blocking plunger 3 are made of the same material, and the linear expansion coefficients of the sealing plunger 2 and the blocking plunger 3 match the linear expansion coefficient of the mirror body 1.

[0049] Through experimental verification, the mirror surface temperature gradient of the highly efficient water-cooled EUV lithography machine mirror of the present invention can be maintained at ≤ 0.01 °C / cm, thus meeting the high requirements of the EUV lithography machine for optical stability.

[0050] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0051] The above specific embodiments of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and deformations made according to the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An efficient water-cooled EUV lithography machine mirror, characterized in that, Comprising: A mirror body (1), inside which a plurality of transverse channels (11) and a plurality of longitudinal channels (12) are formed. The transverse channels (11) and the longitudinal channels (12) communicate with each other and extend to the outside of the mirror body (1). The transverse channels (11) and the longitudinal channels (12) respectively form openings (13) at the edge of the mirror body (1); Sealing plungers (2), a plurality of which are embedded in the openings (13). Among them, at least two of the openings (13) are reserved as a water inlet (41) and a water outlet (42); Blocking plungers (3), a plurality of which are respectively embedded in the transverse channels (11) and the longitudinal channels (12) to form a continuous water-cooling channel (43) between the water inlet (41) and the water outlet (42).

2. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, characterized in that: The main body of the sealing plunger (2) is a cylinder; One end of the sealing plunger (2) is provided with an intersecting first flow-stabilizing surface (21) and a first inclined surface (22).

3. The high-efficiency water-cooled EUV lithography machine mirror according to claim 2, characterized in that: The main body of the blocking plunger (3) is a cylinder; Both ends of the blocking plunger (3) are provided with second flow-stabilizing surfaces (31), and both ends of the blocking plunger (3) are also provided with second inclined surfaces (32). Among them, the second flow-stabilizing surface (31) and the second inclined surface (32) located at the same end intersect.

4. The high-efficiency water-cooled EUV lithography machine mirror according to claim 3, characterized in that: The first inclined surfaces (22) of adjacent sealing plungers (2) are adapted to fit together so that the two first flow-stabilizing surfaces (21) of adjacent sealing plungers (2) are joined to form a continuous flow-stabilizing surface; The second inclined surface (32) of the blocking plunger (3) is adapted to fit against the first inclined surface (22) of the sealing plunger (2) so that the second flow-stabilizing surface (31) of the blocking plunger (3) is joined to the first flow-stabilizing surface (21) of the sealing plunger (2) to form a continuous flow-stabilizing surface.

5. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, characterized in that: At least two lugs (14) are further provided on the mirror body (1); The water inlet (41) and the water outlet (42) are respectively formed on the lugs (14).

6. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, characterized in that: The cross-section of the transverse channels (11) and the longitudinal channels (12) in the radial direction is circular; The centers of the transverse channels (11) and the longitudinal channels (12) in the axial direction are located in the neutral plane of the mirror body (1).

7. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, characterized in that: The transverse channels (11) and the longitudinal channels (12) are formed by drilling.

8. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, characterized in that: The sealing plunger (2) is adhesively bonded to the transverse channel (11) and the longitudinal channel (12); The blocking plunger (3) is adhesively bonded to the transverse channel (11) and the longitudinal channel (12).

9. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, wherein: The material of the mirror body (1) is glass-ceramics; The linear expansion coefficient of the lens body (1) ≤ 1×10 -6 / K.

10. The high-efficiency water-cooled EUV lithography machine mirror according to claim 1, wherein: The sealing plunger (2) and the blocking plunger (3) are made of the same material.

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