A method for assembling a photolithography objective lens and a photolithography objective lens

Abstract

The present application provides an assembly method of a lithography objective lens and a lithography objective lens, comprising a lens, wherein the lens has a first light-transmitting surface and a second light-transmitting surface arranged opposite to each other, and an outer wall surface arranged circumferentially, and also comprises a lens frame carrying the lens, wherein the lens frame is arranged in an annular shape; the inner wall surface of the lens frame is provided with an annular protrusion for abutting against the first light-transmitting surface or the second light-transmitting surface of the lens, and a plurality of glue dispensing grooves; the assembling steps of the lens include: determining the number and specifications of the glue dispensing grooves, and the glue dispensing amount through simulation software; and fixing the lens to the glue dispensing grooves through an adhesive, thereby reducing the amount of adhesive used to reduce the shrinkage stress after the adhesive is cured; at the same time, the lens frame is prevented from directly generating circumferential stress on the lens, and while meeting the assembly stress requirements of the lithography objective lens, the assembly cost of the lithography objective lens can be greatly reduced, and the assembly efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of lithography equipment, and in particular to an assembly method of a lithography objective lens and a lithography objective lens. Background Art

[0002] Optical lens systems are widely used in video equipment, microscopes, telescopes, and various precision instruments. Their performance and stability directly affect the image quality and reliability of the equipment. Traditional optical lens assembly technology mainly relies on physical fixation methods such as mechanical fixtures, fasteners, and washers. Although these methods can stabilize the lens, they also bring some technical difficulties, such as lens deformation caused by mechanical stress, blocking of the light path by fixings, limited assembly accuracy, and complex assembly processes.

[0003] For photolithography objective lenses, the requirements for lens deformation caused by mechanical stress are more stringent, requiring almost zero external stress. There are many mechanical pressure ring designs for reducing stress in the world, which increases the design difficulty and manufacturing cost from a design perspective, and requires manual control of external stress, resulting in extremely stringent requirements for assembly personnel.

[0004] In another way, most lithography objective lenses are also installed and fixed with UV-curing glue based on acrylic. However, with the increase of lens NA (i.e., numerical aperture of the lens) and exposure power, the lens size and thickness are getting larger and larger, and the amount of glue used is also increasing significantly, resulting in stress on the lens when the glue cures and shrinks, which exceeds the design requirements.

[0005] Therefore, how to reduce the assembly cost of the lithography objective and improve the assembly efficiency while ensuring that the lithography objective meets the assembly stress requirements is a problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the present application is to solve the problem of how to reduce the assembly cost of the lithography objective lens and improve the assembly efficiency while ensuring that the lithography objective lens meets the assembly stress requirements in the prior art. Therefore, the present application provides an assembly method of the lithography objective lens and the lithography objective lens, wherein a first assembly gap is reserved between the outer wall surface of the lens and the inner wall surface of the frame to prevent the frame from directly generating circumferential stress on the lens, and a glue dispensing groove is provided so that the outer wall surface of the lens is bonded and fixed to the glue dispensing groove through an adhesive, so that the outer wall surface of the lens is only subjected to the shrinkage stress after the adhesive is cured in the circumferential direction, which can greatly reduce the assembly cost of the lithography objective lens and improve the assembly efficiency while meeting the assembly stress requirements of the lithography objective lens.

[0007] The embodiment of the present application provides an assembly method of a lithography objective lens, comprising a lens, wherein the lens has a first light-transmitting surface and a second light-transmitting surface arranged opposite to each other, and an outer wall surface arranged circumferentially, and also comprises a lens frame carrying the lens, wherein the lens frame is arranged in an annular shape; the inner wall surface of the lens frame is provided with an annular protrusion for abutting against the first light-transmitting surface or the second light-transmitting surface of the lens, and a plurality of glue dispensing grooves;

[0008] The assembly steps of the lens include:

[0009] Determining a first assembly gap between an inner wall surface of the frame and an outer wall surface of the lens according to the size of the lens;

[0010] Determine the number and specifications of the dispensing slots and the dispensing amount through simulation software;

[0011] Install the lens into the frame, and make the first light-transmitting surface or the second light-transmitting surface of the lens abut against the annular protrusion; at the same time, make the outer wall surface of the lens correspond to the inner wall surface of the frame, and leave the first assembly gap;

[0012] Adhesive is dripped into the dispensing groove, and after the adhesive is cured, the assembly of the lens is completed.

[0013] By adopting the above technical solution, a first assembly gap is firstly reserved between the outer wall surface of the lens and the inner wall surface of the frame to prevent the frame from directly generating rigid stress on the lens; further, a plurality of glue-dispensing grooves are arranged on the inner wall surface of the frame, and at this time, the plurality of glue-dispensing grooves can be interconnected through the first assembly gap; and the lens and the frame are fixed by dripping adhesive into the glue-dispensing groove; and when the adhesive in the glue-dispensing groove is cured, the degree of shrinkage in the circumferential direction is greater, thereby reducing the shrinkage stress of the adhesive in the radial direction, so as to reduce the stress generated on the lens when the adhesive is cured.

[0014] In some embodiments, the plurality of glue dispensing grooves are located on the same side of the annular protrusion and are connected to the annular protrusion; and the plurality of glue dispensing grooves on the inner wall surface of the lens frame are evenly distributed in the circumferential direction.

[0015] By adopting the above technical solution, it can be ensured that the stress of the shrinkage of multiple glue dispensing grooves is evenly distributed around the circumference of the lens, thereby ensuring that the force on the lens around the circumference is uniform, thereby ensuring the optical performance of the lens.

[0016] In some embodiments, the specifications of the glue dispensing groove include a first length of the glue dispensing groove in the circumferential direction, and a second length of the glue dispensing groove recessed relative to the inner wall surface;

[0017] Using simulation software, assembling the lens and the frame is simulated, and the simulated stress on the lens is calculated;

[0018] When the simulated stress is greater than a first threshold, the simulated stress is reduced by increasing the number of the glue dispensing slots, increasing the first length of the glue dispensing slots, and reducing the second length.

[0019] By adopting the above technical solution and reducing the second length, the thickness of the adhesive in the dispensing groove in the second length direction can be reduced as much as possible, thereby reducing the shrinkage amplitude of the adhesive in the second length direction to reduce the shrinkage stress of the adhesive.

[0020] At the same time, increasing the number of the glue dispensing grooves and increasing the first length of the glue dispensing grooves can increase the bonding area of ​​the adhesive, thereby reducing the amount of adhesive used to reduce the volume of the adhesive, thereby reducing the shrinkage stress of the adhesive.

[0021] In some embodiments, the frame is arranged in a circular ring shape and has a first thickness; the second length is less than 1 / 10 to 1 / 5 of the first thickness;

[0022] The sum of the first lengths of the plurality of glue dispensing grooves is less than 1 / 2 to 2 / 3 of the circumference of the inner wall of the mirror frame.

[0023] The above technical solution can be used to avoid the second length of the glue dispensing groove being too large, which would cause defects in the rigidity of the frame. At the same time, it can also avoid the adhesive in the glue dispensing groove being too thick in the second length direction, which would cause excessive shrinkage stress.

[0024] Furthermore, it is possible to prevent the second length of the dispensing groove from being too small, which may make it difficult to fully drip the adhesive, resulting in uneven bonding, poor fixing effect, uneven stress on the lens, and other problems.

[0025] Furthermore, it is to avoid that the sum of the first lengths of the plurality of dispensing grooves is too large, which would result in a significant increase in the amount of adhesive used, thereby failing to control the stress on the lens to meet the design requirements.

[0026] In some embodiments, the first thickness is set to 10-30 mm;

[0027] The upper limit of the second length is set to 2-6 mm.

[0028] In some embodiments, the diameter of the lens is 150-500 mm; and the first assembly gap is set to 3-8 mm.

[0029] In some embodiments, the adhesive is configured as a silicone-based glue;

[0030] The silicone-based adhesive has a viscosity of 30,000, a hardness of SHORE A 29.0, a shrinkage rate of 1%, and a breaking elongation of 13%.

[0031] By adopting the above technical solution, the adhesive has a higher viscosity, which can ensure that after the adhesive is dripped in, it will not flow to areas outside the dispensing groove, for example, within the first assembly gap; and the extremely low hardness can make the adhesive play a vibration isolation role to protect the lens; the extremely low shrinkage rate and elongation at break can greatly reduce the stress on the lens after the adhesive is cured.

[0032] In some embodiments, after the number and specifications of the dispensing slots and the dispensing amount are determined by simulation software, corresponding scale lines are marked in the dispensing slots according to the number and specifications of the dispensing slots and the dispensing amount.

[0033] The embodiment of the present application further provides a photolithography objective lens, comprising a lens and a lens frame, wherein the lens and the lens frame are assembled using the assembly method described in any one of the above embodiments;

[0034] The lens has a first light-transmitting surface and a second light-transmitting surface that are arranged opposite to each other, and an outer wall surface that is arranged in a circumferential direction;

[0035] The mirror frame is arranged in a ring shape, and the inner wall surface of the mirror frame is provided with a ring-shaped protrusion and a plurality of glue dispensing grooves;

[0036] The lens is fixed in the frame, and the first light-transmitting surface or the second light-transmitting surface of the lens abuts against the annular protrusion of the frame, and a first assembly gap is left between the outer wall surface of the lens and the inner wall surface of the frame;

[0037] The outer wall surface of the lens is bonded and fixed to the multiple glue dispensing grooves of the frame by using silicone-based glue.

[0038] By adopting the above technical scheme, a first assembly gap is retained between the outer wall surface of the lens and the inner wall surface of the frame to prevent the frame from directly generating rigid stress on the lens; further, a plurality of glue dispensing grooves are arranged on the inner wall surface of the frame, and at this time, the plurality of glue dispensing grooves can be interconnected through the first assembly gap; and the outer wall surface of the lens and the plurality of glue dispensing grooves of the frame are bonded and fixed by silicone-based glue; thereby, when the silicone-based glue is cured, the degree of shrinkage in the circumferential direction is greater, thereby reducing the radial shrinkage stress of the silicone-based glue, so as to reduce the stress generated on the lens when the silicone-based glue is cured.

[0039] Other features and corresponding beneficial effects of the present application are described in the latter part of the specification, and it should be understood that at least some of the beneficial effects become obvious from the records in the specification of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of the three-dimensional structure of a lithography objective lens according to an embodiment of the present application;

[0041] Figure 2A structural cross-sectional view of a photolithography objective lens according to an embodiment of the present application;

[0042] Figure 3 A top view of the structure of a lithography objective lens according to an embodiment of the present application;

[0043] Figure 4 A top view of a partial structure of a lens frame of a photolithography objective lens according to an embodiment of the present application;

[0044] Figure 5 A stress simulation result diagram of a photolithography objective lens provided with three dispensing grooves according to an embodiment of the present application;

[0045] Figure 6 A stress simulation result diagram of a lithography objective lens with six dispensing grooves in an embodiment of the present application.

[0046] Description of reference numerals:

[0047] 1. Lenses;

[0048] 2. Picture frame;

[0049] 21. Glue dispensing groove; 22. Ring-shaped protrusion; 23. Scale line;

[0050] 3. First assembly gap;

[0051] L, first length; H, second length. DETAILED DESCRIPTION

[0052] The following specific embodiments illustrate the implementation of the present application, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this application are limited to the implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide a deep understanding of the present application, the following description will include many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0053] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0054] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0055] In the description of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply 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 on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description created by the present application, unless otherwise specified, "multiple" means two or more.

[0056] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0058] See also Figure 1~Figure 4 , Figure 1 is a schematic diagram of the three-dimensional structure of the lithography objective lens of an embodiment of the present application, Figure 2 is a structural cross-sectional view of a lithography objective lens according to an embodiment of the present application, Figure 3 This is a top view of the structure of the lithography objective lens of an embodiment of the present application. Figure 4 It is a top view of the partial structure of the lens frame of the lithography objective lens according to an embodiment of the present application.

[0059] like Figures 1 to 4As shown, the embodiment of the present application provides an assembly method of a lithography objective lens, comprising a lens 1, wherein the lens 1 has a first light-transmitting surface and a second light-transmitting surface arranged opposite to each other, and an outer wall surface arranged circumferentially, and further comprises a lens frame 2 carrying the lens 1, wherein the lens frame 2 is arranged in an annular shape; the inner wall surface of the lens frame 2 is provided with an annular protrusion 22 for abutting against the first light-transmitting surface or the second light-transmitting surface of the lens 1, and a plurality of glue dispensing grooves 21;

[0060] The assembly steps of the lens 1 include:

[0061] According to the size of the lens 1, determine the first assembly gap 3 between the inner wall surface of the frame 2 and the outer wall surface of the lens 1;

[0062] Determine the number and specifications of the glue dispensing slots 21 and the glue dispensing amount through the simulation software;

[0063] The lens 1 is installed into the frame 2, and the first light-transmitting surface or the second light-transmitting surface of the lens 1 is in contact with the annular protrusion 22; at the same time, the outer wall surface of the lens 1 is made to correspond to the inner wall surface of the frame 2, and a first assembly gap 3 is left;

[0064] Adhesive is dripped into the dispensing groove 21 , and after the adhesive is cured, the assembly of the lens 1 is completed.

[0065] It should be noted that during the assembly process of the lithography objective lens, the stress generated by the assembly methods such as clamping or bonding will affect the surface accuracy of the lens 1, thereby affecting the resolution and imaging quality of the lithography. Specifically, the stress may cause a slight deformation or displacement of the lens 1, thereby changing the propagation path and focusing characteristics of the light, and ultimately affecting the accuracy and uniformity of the lithography.

[0066] Therefore, the first light-transmitting surface or the second light-transmitting surface of the lens 1 is abutted against the annular protrusion 22, so that the larger supporting force of the annular protrusion 22 can act evenly on the axial direction of the lens 1. On the one hand, the influence of the supporting force of the annular protrusion 22 on the lens 1 is greatly reduced. On the other hand, since the annular protrusion 22 is a rigid support, the influence of the supporting force of the annular protrusion 22 can be predicted and controlled.

[0067] Furthermore, it should be noted that in the field of lithography objective lens assembly, the main function of the adhesive is to limit the position of the lens 1 to prevent slight vibration from causing the lens 1 to shift or slide. Therefore, the adhesive only needs to be able to play a bonding role between the frame 2 and the lens 1, and the bonding strength requirement is relatively low; at the same time, since the shrinkage stress of the adhesive is difficult to control accurately, and the lens 1 is extremely sensitive to stress, when the adhesive is used to assemble the lens 1, it is necessary to greatly reduce the stress generated by the adhesive on the lens 1, and it is best not to generate stress, and only generate force when the lens 1 shifts to limit the displacement of the lens 1.

[0068] In the circumferential direction of the lens 1, a first assembly gap 3 is first reserved between the outer wall surface of the lens 1 and the inner wall surface of the frame 2 to prevent the frame 2 from directly generating rigid stress on the lens 1; further, a plurality of glue-dispensing grooves 21 are provided on the inner wall surface of the frame 2, and at this time, the plurality of glue-dispensing grooves 21 can be interconnected through the first assembly gap 3; and the lens 1 and the frame 2 are fixed by dripping adhesive into the glue-dispensing grooves 21; and when the adhesive in the glue-dispensing grooves 21 is cured, the degree of contraction in the circumferential direction is greater, thereby reducing the contraction stress of the adhesive in the radial direction, so as to reduce the stress generated on the lens 1 when the adhesive is cured.

[0069] Furthermore, the cured adhesive can play a role in shock absorption and buffering, thereby protecting the lens 1 .

[0070] In one embodiment, the plurality of glue-dispensing grooves 21 are located on the same side of the annular protrusion 22 and connected to the annular protrusion 22; and the plurality of glue-dispensing grooves 21 on the inner wall of the frame 2 are evenly distributed in the circumferential direction. Thus, it is ensured that the stress of the plurality of glue-dispensing grooves 21 contracting is evenly distributed in the circumferential direction of the lens 1, thereby ensuring that the force on the lens 1 in the circumferential direction is even, thereby ensuring the optical performance of the lens 1.

[0071] In one embodiment, eight dispensing grooves 21 are provided and are evenly distributed in the circumferential direction.

[0072] In one embodiment, the specifications of the glue dispensing groove 21 include a first length L of the glue dispensing groove 21 in the circumferential direction, and a second length H of the glue dispensing groove 21 recessed relative to the inner wall surface;

[0073] Using simulation software, the lens 1 and the frame 2 are assembled and simulated, and the simulated stress on the lens 1 is calculated;

[0074] When the simulated stress is greater than the first threshold, the simulated stress is reduced by increasing the number of the glue dispensing slots 21 , increasing the first length L of the glue dispensing slots 21 , and reducing the second length H.

[0075] By reducing the second length H, the thickness of the adhesive in the dispensing groove 21 in the direction of the second length H can be reduced as much as possible, thereby reducing the shrinkage amplitude of the adhesive in the direction of the second length H and reducing the shrinkage stress of the adhesive.

[0076] At the same time, increasing the number of the glue dispensing grooves 21 and increasing the first length L of the glue dispensing grooves 21 can increase the adhesive bonding area, thereby reducing the amount of adhesive used to reduce the adhesive volume, thereby reducing the shrinkage stress of the adhesive.

[0077] It should be noted that an increase in the number of the glue dispensing grooves 21 will lead to an increase in the glue dispensing process and the processing cost of the frame 2; an increase in the first length L of the glue dispensing grooves 21 will lead to a decrease in the rigid structure strength of the frame 2.

[0078] In one embodiment, the lower limit and upper limit of the number of the glue dispensing slots 21 are preset; the lower limit and upper limit of the first length L are preset; and the lower limit of the number of the glue dispensing slots 21 and the lower limit of the first length L are preset as preset values.

[0079] The preset value of the second length H is 5 mm; wherein, the preset value of the second length H is determined according to the accuracy of the dispensing process and the viscosity of the adhesive to ensure that the adhesive can be fully filled; at the same time, it is ensured that the preset value of the second length H will not cause strength defects of the frame 2.

[0080] In one embodiment, when the simulated stress is greater than the first threshold, the number of glue dispensing grooves 21 is preferentially increased, and after the upper limit of the number of glue dispensing grooves 21 is reached, the first length L is increased; at this time, while the glue dispensing amount remains unchanged, the bonding area of ​​the adhesive can be increased, and the height of the adhesive can be reduced, so that the shrinkage stress of the adhesive is more dispersed, thereby reducing the stress on the lens 1.

[0081] In one embodiment, while keeping the height of the glue dispensing amount unchanged, the second length H is reduced. On the one hand, the thickness of the adhesive in the glue dispensing groove 21 in the direction of the second length H is reduced, thereby reducing the shrinkage amplitude of the adhesive in the direction of the second length H to reduce the shrinkage stress of the adhesive; on the other hand, the glue dispensing amount can be reduced and the use of adhesive can be reduced.

[0082] In one embodiment, after the number and specifications of the dispensing slots 21 and the amount of dispensing are determined by simulation software, corresponding scale lines 23 are marked in the dispensing slots 21 according to the number and specifications of the dispensing slots 21 and the amount of dispensing, so as to facilitate accurate control of the amount of dispensing of the adhesive dripped into the dispensing slots 21.

[0083] See also Figure 5 and Figure 6 , Figure 5 The stress simulation result diagram of the lithography objective lens with three dispensing grooves in the embodiment of the present application is shown in FIG. Figure 6 A stress simulation result diagram of a lithography objective lens with six dispensing grooves in an embodiment of the present application.

[0084] In one example, Figure 5 and Figure 6 As shown, when the number of the dispensing grooves 21 is 3, the range of the surface deformation of the lens 1 after being subjected to stress is between +0.0249wave and -0.0310wave, and the distribution of the degree of deformation under stress is extremely uneven; when the number of the dispensing grooves 21 is 6, the range of the surface deformation of the lens 1 after being subjected to stress is between +0.00125wave and -0.00473wave, and the extreme value of the deformation is significantly reduced, indicating that the stress distribution of the lens 1 is more uniform at this time.

[0085] It should be noted that acrylic-based glue has a high viscosity, dries quickly, and cures quickly, and can cure within a few milliseconds. At the same time, it has good transparency and high adhesion, and can be used in occasions with high transparency requirements. In addition, it can firmly bond various materials and has a certain shear resistance.

[0086] Therefore, in another example, when the glue dispensing groove 21 is not provided, the prior art generally uses acrylic base glue to bond the lens 1; at this time, when the acrylic base glue is used for bonding and the glue dispensing groove 21 is not provided, after the lens 1 is directly bonded to the frame 2, the range of surface deformation caused by the stress on the lens 1 is: +0.0513wave~-0.0845wave, which is significantly higher than +0.0249wave~-0.0310wave;

[0087] In one embodiment, the frame 2 is arranged in a circular ring shape and has a first thickness; the second length H is less than 1 / 10 to 1 / 5 of the first thickness;

[0088] The sum of the first lengths L of the plurality of glue dispensing grooves 21 is smaller than 1 / 2 to 2 / 3 of the circumference of the inner wall surface of the lens frame 2 .

[0089] This can prevent the second length H of the glue dispensing groove 21 from being too large, causing defects in the rigidity of the frame 2. At the same time, it can prevent the thickness of the adhesive in the glue dispensing groove 21 in the direction of the second length H from being too large, causing excessive shrinkage stress.

[0090] Furthermore, it is possible to prevent the second length H of the glue dispensing groove 21 from being too small, which may make it difficult to fully drip the adhesive, resulting in uneven bonding, poor fixing effect, uneven stress on the lens 1, and other problems.

[0091] Furthermore, it is necessary to avoid the sum of the first lengths L of the plurality of adhesive dispensing grooves 21 being too large, which would result in a significant increase in the amount of adhesive used, thereby failing to control the stress on the lens 1 to meet the design requirements.

[0092] In one embodiment, the first thickness is set to 10-30 mm;

[0093] The upper limit of the second length H is set to 2-6 mm.

[0094] In one embodiment, the diameter of the lens 1 is 150-500 mm; the first assembly gap 3 is set to 3-8 mm.

[0095] In one embodiment, the diameter of the lens 1 is 150 mm; the first assembly gap 3 is set to 4 mm; the first thickness is set to 15 mm; and the second length H is set to 3 mm.

[0096] In one embodiment, the adhesive is configured as a silicone-based glue;

[0097] The viscosity of the silicone-based glue is 30,000; the hardness is SHORE A 29.0; the shrinkage rate is 1%; and the elongation at break is 13%.

[0098] By adopting the above technical solution, the adhesive has a greater viscosity, which can ensure that after the adhesive is dripped in, it will not flow to the area outside the dispensing groove 21, for example, within the first assembly gap 3; and the extremely low hardness can make the adhesive play a vibration isolation role to protect the lens 1; the extremely low shrinkage rate and elongation at break can greatly reduce the stress on the lens 1 after the adhesive is cured.

[0099] The embodiment of the present application further provides a lithography objective lens, comprising a lens 1 and a lens frame 2, wherein the lens 1 and the lens frame 2 are assembled using the assembly method in any of the above embodiments;

[0100] The lens 1 has a first light-transmitting surface and a second light-transmitting surface arranged opposite to each other, and an outer wall surface arranged in a circumferential direction;

[0101] The lens frame 2 is arranged in a ring shape, and the inner wall surface of the lens frame 2 is provided with a ring-shaped protrusion 22 and a plurality of glue dispensing grooves 21;

[0102] The lens 1 is fixed in the frame 2, and the first light-transmitting surface or the second light-transmitting surface of the lens 1 abuts against the annular protrusion 22 of the frame 2, and a first assembly gap 3 is left between the outer wall surface of the lens 1 and the inner wall surface of the frame 2;

[0103] The outer wall surface of the lens 1 is bonded and fixed to the plurality of glue dispensing grooves 21 of the frame 2 by using silicone-based glue.

[0104] In the lithography objective, a first assembly gap 3 is reserved between the outer wall surface of the lens 1 and the inner wall surface of the frame 2 to prevent the frame 2 from directly generating rigid stress on the lens 1; further, a plurality of glue dispensing grooves 21 are arranged on the inner wall surface of the frame 2, and at this time, the plurality of glue dispensing grooves 21 can be interconnected through the first assembly gap 3; and the outer wall surface of the lens 1 and the plurality of glue dispensing grooves 21 of the frame 2 are bonded and fixed by silicone-based glue; thereby, when the silicone-based glue is cured, the degree of shrinkage in the circumferential direction is greater, thereby reducing the radial shrinkage stress of the silicone-based glue, so as to reduce the stress generated on the lens 1 when the silicone-based glue is cured.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for assembling a photolithography objective lens, comprising a lens having a first light-transmitting surface and a second light-transmitting surface arranged opposite to each other, and an outer wall surface arranged circumferentially, characterized in that: It also includes a frame for carrying the lens, the frame is arranged in a ring shape; the inner wall surface of the frame is provided with a ring-shaped protrusion for abutting against the first light-transmitting surface or the second light-transmitting surface of the lens, and a plurality of glue dispensing grooves; The assembly steps of the lens include: Determining a first assembly gap between an inner wall surface of the frame and an outer wall surface of the lens according to the size of the lens; Determine the number and specifications of the dispensing slots and the dispensing amount through simulation software; Install the lens into the frame, and make the first light-transmitting surface or the second light-transmitting surface of the lens abut against the annular protrusion; at the same time, make the outer wall surface of the lens correspond to the inner wall surface of the frame, and leave the first assembly gap; Dropping adhesive into the dispensing groove, and completing the assembly of the lens after the adhesive is cured; The plurality of glue dispensing grooves are located on the same side of the annular protrusion and connected to the annular protrusion; and the plurality of glue dispensing grooves on the inner wall of the lens frame are evenly distributed in the circumferential direction; The specifications of the glue dispensing groove include a first length of the glue dispensing groove in the circumferential direction and a second length of the glue dispensing groove recessed relative to the inner wall surface; Using simulation software, assembling the lens and the frame is simulated, and the simulated stress on the lens is calculated; Preset the lower limit and upper limit of the number of dispensing slots; the lower limit and upper limit of the first length; and set the lower limit of the number of dispensing slots and the lower limit of the first length as preset values; When the simulation stress is greater than the first threshold, the number of the dispensing slots is increased first, and after the upper limit of the number of the dispensing slots is reached, the first length is increased; The adhesive is configured as silicone-based glue; The viscosity of the silicone-based glue is 30,000; the hardness is SHORE A 29.0; the shrinkage is 1%; and the elongation at break is 13%; After determining the number and specifications of the dispensing slots and the amount of glue dispensed by the simulation software, corresponding scale lines are marked in the dispensing slots according to the number and specifications of the dispensing slots and the amount of glue dispensed.

2. The method for assembling a lithography objective lens according to claim 1, characterized in that: The frame is arranged in a circular ring shape and has a first thickness; the second length is less than 1 / 10 to 1 / 5 of the first thickness; The sum of the first lengths of the plurality of glue dispensing grooves is less than 1 / 2 to 2 / 3 of the circumference of the inner wall of the mirror frame.

3. The method for assembling a lithography objective lens according to claim 2, characterized in that: The first thickness is set to 10-30 mm; The upper limit of the second length is set to 2-6 mm.

4. The method for assembling a lithography objective lens according to claim 1, characterized in that: The diameter of the lens is 150-500 mm; the first assembly gap is set to 3-8 mm.

5. A photolithography objective lens, characterized in that: It comprises a lens and a frame, and the lens and the frame are assembled by the assembly method according to any one of claims 1 to 4; The lens has a first light-transmitting surface and a second light-transmitting surface that are arranged opposite to each other, and an outer wall surface that is arranged in a circumferential direction; The mirror frame is arranged in a ring shape, and the inner wall surface of the mirror frame is provided with a ring-shaped protrusion and a plurality of glue dispensing grooves; The lens is fixed in the frame, and the first light-transmitting surface or the second light-transmitting surface of the lens abuts against the annular protrusion of the frame, and a first assembly gap is left between the outer wall surface of the lens and the inner wall surface of the frame; The outer wall surface of the lens is bonded and fixed to the multiple glue dispensing grooves of the frame by using silicone-based glue.

Images