Lithographic objective lens and lithographic apparatus

Abstract

The utility model discloses a photoetching objective lens and photoetching equipment, and relates to the technical field of optical systems, the photoetching objective lens is provided with an object side and an image side which are correspondingly arranged along the direction of an optical axis, and the photoetching objective lens comprises a first lens to a twentieth lens which are sequentially arranged from the object side to the image side; wherein the first lens and the twentieth lens are plane lenses, and the second lens, the third lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens, the eighteenth lens and the nineteenth lens have positive focal power; the fourth lens, the fifth lens, the eleventh lens, the twelfth lens, the sixteenth lens and the seventeenth lens have negative focal power; the exposure view field area of the photoetching objective lens is larger than or equal to 72 mm * 72 mm, and the resolution ratio is smaller than 780 nm. According to the technical scheme provided by the utility model, through the design and arrangement of twenty optical lenses, the photoetching objective lens simultaneously achieves the effects of high resolution and large field of view.

Description

Technical Field

[0001] The utility model relates to the technical field of optical systems, in particular to a photolithography objective lens and a photolithography device. Background Art

[0002] With the rapid development of microelectronics technology in recent years, there are more and more scenarios for the use of large-scale integrated circuits, so the demand for microelectronic devices and micro-processing technology is also increasing. With its wide application field and rapid technological updates, photolithography technology is driving the rapid development of fine processing technology. The photolithography machine uses a technology similar to photo printing to print the fine graphics on the mask onto the silicon wafer through light exposure, which is applied in chip manufacturing, LED manufacturing and packaging.

[0003] With the continuous updating of lithography technology, there is a requirement to expose more precise lines on larger chip areas (resolution requirements). Therefore, the demand for lithography lenses used in large exposure fields is also increasing. However, there are currently few such lens products that have both large target areas and high resolution. Utility Model Content

[0004] The main purpose of the utility model is to provide a photolithography objective lens and a photolithography device, and in particular to a photolithography objective lens which aims to achieve high resolution and a large field of view.

[0005] To achieve the above-mentioned purpose, the utility model provides a lithography objective lens, which has an object side and an image side correspondingly arranged along the optical axis direction, and comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, a thirteenth lens, a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens, an eighteenth lens, a nineteenth lens, and a twentieth lens arranged in sequence from the object side to the image side;

[0006] Among them, the first lens and the twentieth lens are set as plane lenses, the second lens, the third lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens, the eighteenth lens, and the nineteenth lens have positive optical power; the fourth lens, the fifth lens, the eleventh lens, the twelfth lens, the sixteenth lens, and the seventeenth lens have negative optical power; so that the exposure field area of ​​the lithography objective lens is greater than or equal to 72mm×72mm, and the resolution is less than 780nm.

[0007] In one embodiment, the object side surface and the image side surface of the first lens are both configured as planes;

[0008] The object side surface of the second lens is set to be a plane, and the image side surface has a curvature radius of R22, -135mm≤R22≤-125mm;

[0009] The object side radius of the third lens is R31, and the image side radius is R32, 80mm≤R31≤85mm, 380mm≤R32≤390mm;

[0010] The fourth lens has an object side radius of R41 and an image side radius of R42, wherein -3650mm≤R41≤-3600mm, and 45mm≤R42≤55mm;

[0011] The object side radius of the fifth lens is R51, the image side radius is R52, -76mm≤R51≤-60mm, 1950mm≤R52≤2050mm;

[0012] The radius of the object side surface of the sixth lens is R61, and the radius of the image side surface is R62, -105mm≤R61≤-95mm, -110mm≤R62≤-93mm;

[0013] The seventh lens has an object side radius of R71 and an image side radius of R72, 630 mm ≤ R71 ≤ 650 mm, and -400 mm ≤ R72 ≤ -380 mm;

[0014] The object side radius of the eighth lens is R81, the image side radius is R82, 555mm≤R81≤595mm, -270mm≤R82≤-255mm;

[0015] The radius of the object side surface of the ninth lens is R91, and the radius of the image side surface is R92, 190mm≤R91≤200mm, 600mm≤R92≤620mm;

[0016] The object side radius of the tenth lens is R101, the image side radius is R102, -390mm≤R101≤-370mm, -275mm≤R102≤-260mm;

[0017] The object side radius of the eleventh lens is R111, the image side radius is R112, -175mm≤R111≤-160mm, 115mm≤R112≤125mm;

[0018] The object side radius of the twelfth lens is R121, and the image side radius is R122, -130mm≤R121≤-115mm, -165mm≤R122≤-150mm;

[0019] The object side radius of the thirteenth lens is R131, the image side radius is R132, 285mm≤R131≤305mm, -285mm≤R132≤-265mm;

[0020] The object side radius of the fourteenth lens is R141, the image side radius is R142, 170mm≤R141≤185mm, -550mm≤R142≤-530mm;

[0021] The object side radius of the fifteenth lens is R151, and the image side radius is R152, 100mm≤R151≤110mm, -270mm≤R152≤-255mm;

[0022] The object side radius of the sixteenth lens is R161, the image side radius is R162, -200mm≤R161≤-185mm, 335mm≤R162≤355mm;

[0023] The object side radius of the seventeenth lens is R171, and the image side radius is R172, 100mm≤R171≤115mm, 55mm≤R172≤65mm;

[0024] The object side radius of the eighteenth lens is R181, the image side radius is R182, 65mm≤R181≤75mm, 220mm≤R182≤230mm;

[0025] The object side radius of the nineteenth lens is R191, and the image side radius is R192, 80mm≤R191≤90mm, 115mm≤R192≤125mm;

[0026] The object-side surface and the image-side surface of the 20th lens are both set to be planes.

[0027] In one embodiment, the thickness of the second lens is G2, 31 mm ≤ G2 ≤ ​​33 mm;

[0028] The thickness of the third lens is G3, 47mm≤G3≤51mm;

[0029] The thickness of the fourth lens is G4, 25mm≤G4≤30mm;

[0030] The thickness of the fifth lens is G5, 7mm≤G5≤10mm;

[0031] The thickness of the sixth lens is G6, 37 mm ≤ G6 ≤ 42 mm;

[0032] The thickness of the seventh lens is G7, 42mm≤G7≤50mm;

[0033] The thickness of the eighth lens is G8, 10mm≤G8≤13mm;

[0034] The thickness of the ninth lens is G9, 18 mm ≤ G9 ≤ 22 mm;

[0035] The thickness of the tenth lens is G10, 45mm≤G10≤50mm;

[0036] The thickness of the eleventh lens is G11, 20 mm ≤ G11 ≤ 23 mm;

[0037] The thickness of the twelfth lens is G12, 18mm≤G12≤23mm;

[0038] The thickness of the thirteenth lens is G13, 12mm≤G13≤15mm;

[0039] The thickness of the fourteenth lens is G14, 40 mm ≤ G14 ≤ 45 mm;

[0040] The thickness of the fifteenth lens is G15, 22mm≤G15≤25mm;

[0041] The thickness of the sixteenth lens is G16, 10 mm ≤ G16 ≤ 12 mm;

[0042] The thickness of the seventeenth lens is G17, 15 mm ≤ G17 ≤ 20 mm;

[0043] The thickness of the eighteenth lens is G18, 14 mm ≤ G18 ≤ 20 mm;

[0044] The thickness of the nineteenth lens is G19, 33mm≤G19≤36mm.

[0045] In one embodiment, the refractive index of the second lens is n2, 1.4≤n2≤1.5;

[0046] The refractive index of the third lens is n3, 1.45≤n3≤1.55;

[0047] The refractive index of the fourth lens is n4, 1.6≤n4≤1.65;

[0048] The refractive index of the fifth lens is n5, 1.4≤n5≤1.5;

[0049] The refractive index of the sixth lens is n6, 1.45≤n6≤1.55;

[0050] The refractive index of the seventh lens is n7, 1.6≤n7≤1.65;

[0051] The refractive index of the eighth lens is n8, 1.45≤n8≤1.55;

[0052] The refractive index of the ninth lens is n9, 1.45≤n9≤1.55;

[0053] The refractive index of the tenth lens is n10, 1.45≤n10≤1.55; the refractive index of the eleventh lens is n11, 1.55≤n11≤1.6; the refractive index of the twelfth lens is n12, 1.55≤n12≤1.6; the refractive index of the thirteenth lens is n13, 1.45≤n13≤1.55; the refractive index of the fourteenth lens is n14, 1.45≤n14≤1.55; the refractive index of the fifteenth lens is n15, 1.45≤n15≤1.55; the refractive index of the sixteenth lens is n16, 1.55≤n16≤1.6; the refractive index of the seventeenth lens is n17, 1.4≤n17≤1.5; the refractive index of the eighteenth lens is n18, 1.45≤n18≤1.55; and the refractive index of the nineteenth lens is n19, 1.6≤n19≤1.65. In one embodiment, the focal length of the lithography objective lens is f, the focal length of the second lens is f2, 0.2≤|f2 / f|≤0.4;

[0054] The focal length of the third lens is f3, 0.1≤|f3 / f|≤0.4;

[0055] The focal length of the fourth lens is f4, 0.1≤|f4 / f|≤0.3;

[0056] The focal length of the fifth lens is f5, 0.1≤|f5 / f|≤0.3;

[0057] The focal length of the sixth lens is f6, 2≤|f6 / f|≤4;

[0058] The focal length of the seventh lens is f7, 0.4≤|f7 / f|≤0.6;

[0059] The focal length of the eighth lens is f8, 0.4≤|f8 / f|≤0.6;

[0060] The focal length of the ninth lens is f9, 0.6≤|f9 / f|≤0.9;

[0061] The focal length of the tenth lens is f10, 2≤|f10 / f|≤4;

[0062] The focal length of the eleventh lens is f11, 0.1≤|f11 / f|≤0.5;

[0063] The focal length of the twelfth lens is f12, 1≤|f12 / f|≤3;

[0064] The focal length of the thirteenth lens is f13, 0.3≤|f13 / f|≤0.6; the focal length of the fourteenth lens is f14, 0.3≤|f14 / f|≤0.6;

[0065] The focal length of the fifteenth lens is f15, 0.1≤|f15 / f|≤0.4;

[0066] The focal length of the sixteenth lens is f16, 0.2≤|f16 / f|≤0.4;

[0067] The focal length of the seventeenth lens is f17, 0.3≤|f17 / f|≤0.6;

[0068] The focal length of the eighteenth lens is f18, 0.2≤|f18 / f|≤0.6;

[0069] The focal length of the nineteenth lens is f19, 0.3≤|f19 / f|≤0.6.

[0070] In one embodiment, the total length of the lithography objective lens is TTL, 1.2≤TTL / f≤1.5, 1000mm≤TTL≤1250mm.

[0071] In one embodiment, the image-side numerical aperture of the lithography objective is NA, and NA≥0.24.

[0072] In one embodiment, the aperture number of the lithography objective lens is F, 1.8≤F≤2.1.

[0073] In one embodiment, the zoom ratio of the lithography objective is A, 0.24≤A≤0.26.

[0074] The utility model also provides a lithography device, the lithography device includes a lithography objective lens, the lithography objective lens has an object side and an image side correspondingly arranged along an optical axis direction, the lithography objective lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, a thirteenth lens, a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens, an eighteenth lens, a nineteenth lens, and a twentieth lens arranged in sequence from the object side to the image side;

[0075] Among them, the first lens and the twentieth lens are set as plane lenses, the second lens, the third lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens, the eighteenth lens, and the nineteenth lens have positive optical power; the fourth lens, the fifth lens, the eleventh lens, the twelfth lens, the sixteenth lens, and the seventeenth lens have negative optical power; so that the exposure field area of ​​the lithography objective lens is greater than or equal to 72mm×72mm, and the resolution is less than 780nm.

[0076] The technical solution of the utility model forms a double telecentric structure by designing and arranging twenty optical lenses. The double telecentric system has the characteristic that the magnification is less affected by the change of object distance and image distance, which means that during the imaging process, the double telecentric system can maintain a stable magnification within the entire depth of field, so the imaging quality will not change due to the change of the distance between the object and the photolithography objective lens. It has a higher resolution. Compared with the traditional telecentric system, the double telecentric system usually has a larger depth of field, which means that it can cover a wider observation range, which is very beneficial for scenes that need to observe different depth levels. The photolithography objective lens can achieve high resolution and a large field of view at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0078] Figure 1 A schematic structural diagram of an embodiment of a photolithography objective lens provided by the utility model;

[0079] Figure 2 for Figure 1 MTF curve of the lithography objective lens at 640lp / mm;

[0080] Figure 3 for Figure 1 TFM curve of the medium lithography objective at 640lp / mm;

[0081] Figure 4 for Figure 1 Spot diagram of the medium lithography objective;

[0082] Figure 5 for Figure 1 Schematic diagram of the field curvature of the photolithography objective.

[0083] Description of Figure Numbers:

[0084] 100. photolithography objective lens; 1. first lens; 2. second lens; 3. third lens; 4. fourth lens; 5. fifth lens; 6. sixth lens; 7. seventh lens; 8. eighth lens; 9. ninth lens; 10. tenth lens; 11. eleventh lens; 12. twelfth lens; 13. thirteenth lens; 14. fourteenth lens; 15. fifteenth lens; 16. sixteenth lens; 17. seventeenth lens; 18. eighteenth lens; 19. nineteenth lens; 20. twentieth lens; 21. aperture.

[0085] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0086] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0087] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0088] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0089] With the continuous updating of lithography technology, there is a requirement to expose more precise lines on larger chip areas (resolution requirements). Therefore, the demand for lithography lenses used in large exposure fields is also increasing. However, there are currently few such lens products that have both large target areas and high resolution.

[0090] The utility model provides a photolithography objective lens.

[0091] See also Figure 1 In one embodiment of the utility model, the lithography objective lens 100 has an object side and an image side correspondingly arranged along the optical axis direction, and the lithography objective lens 100 includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, an eleventh lens 11, a twelfth lens 12, a thirteenth lens 13, a fourteenth lens 14, a fifteenth lens 15, a sixteenth lens 16, a seventeenth lens 17, an eighteenth lens 18, a nineteenth lens 19, and a twentieth lens 20 arranged in sequence from the object side to the image side;

[0092] Wherein, the first lens 1 and the 20th lens 20 are set as plane lenses, the second lens 2, the third lens 3, the sixth lens 6, the seventh lens 7, the eighth lens 8, the ninth lens 9, the tenth lens 10, the thirteenth lens 13, the fourteenth lens 14, the fifteenth lens 15, the eighteenth lens 18, and the nineteenth lens 19 have positive optical power; the fourth lens 4, the fifth lens 5, the eleventh lens 11, the twelfth lens 12, the sixteenth lens 16, and the seventeenth lens 17 have negative optical power; so that the exposure field area of ​​the lithography objective 100 is greater than or equal to 72 mm×72 mm, and the resolution is less than 780 nm.

[0093] The technical solution of the utility model adopts the design and arrangement of twenty optical lenses to make the lithography objective 100 achieve high resolution and large field of view at the same time. Among them, the first lens 1 is a protective glass, and the twentieth lens 20 is a protective glass. The second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 greatly correct the system distortion, the sixth lens 6 and the seventh lens 7 can correct chromatic aberration; the eighth lens 8 can optimize the system spherical aberration and correct the system distortion at the same time; the ninth lens 9 can correct the system spherical aberration and off-axis aberration; the tenth lens 10 can optimize the system spherical aberration and correct the system distortion at the same time; the eleventh lens 11, the twelfth lens 12, the thirteenth lens 13, the fourteenth lens 14, the fifteenth lens 15 and the sixteenth lens 16 optimize the system spherical aberration and coma through the combination of positive and negative lenses, and the seventeenth lens 17, the eighteenth lens 18 and the nineteenth lens 19 can correct the system chromatic aberration and spherical aberration and image curvature, thereby improving the imaging quality. In addition, the design and arrangement of the twenty optical lenses form a double telecentric structure. The double telecentric system has the characteristic that the magnification is less affected by the change of object distance and image distance, which means that during the imaging process, the double telecentric system can maintain a stable magnification within the entire depth of field, so the image quality will not change due to the change of the distance between the object and the camera, which makes it have excellent performance in precision measurement and detection. The double telecentric system usually has a higher resolution, which is very useful for application scenarios that need to capture subtle features. Compared with the traditional telecentric system, the double telecentric system usually has a larger depth of field, which means that it can cover a wider range of observation, which is very beneficial for scenes that need to observe different depth levels. The double telecentric system has a higher telecentricity. Telecentricity refers to the angle at which the main light deviates from the optical axis. The smaller the angle, the better the telecentricity and the smaller the magnification error of the lens. The performance in the measurement process is: within the depth of field, the magnification of the object is guaranteed to be the same at different working distances. It is an important factor to make up for the disadvantage of ordinary industrial lenses that "near is large and far is small".

[0094] The radius of curvature and thickness of the lens are very important parameters in the optical system, which directly affect the imaging quality and performance of the optical system. The radius of curvature refers to the curvature of the lens surface, which determines the refraction of light when passing through the lens. The smaller the radius of curvature, the greater the curvature of the lens, and vice versa. In the optical system, the size of the radius of curvature directly affects the focal length and focal length of the lens, thereby affecting the imaging effect of the entire system. The radius of curvature determines the degree of refraction of light by the lens. The smaller the radius of curvature, the stronger the refractive power of the lens, and vice versa. Therefore, the choice of the radius of curvature directly affects the focal length and magnification of the optical system. The thickness of the lens is also an important factor affecting the performance of the optical system. The lithography objective lens 100 designed in the present invention meets the following requirements: the object side surface and the image side surface of the first lens 1 are both set as planes; the object side surface of the second lens 2 is set as a plane, and the image side surface curvature radius is R22, -135mm≤R22≤-125mm; the object side surface radius of the third lens 3 is R31, and the image side surface radius is R32, 80mm≤R31≤85mm, 380mm≤R32≤390mm; the object side surface radius of the fourth lens 4 is R41, and the image side surface radius is R42, -3650mm ≤R41≤-3600mm, 45mm≤R42≤55mm; the object side radius of the fifth lens 5 is R51, and the image side radius is R52, -76mm≤R51≤-60mm, 1950mm≤R52≤2050mm; the object side radius of the sixth lens 6 is R61, and the image side radius is R62, -105mm≤R61≤-95mm, -110mm≤R62≤-93mm; the object side radius of the seventh lens 7 is R71, and the image side radius is R72, 63 0mm≤R71≤650mm, -400mm≤R72≤-380mm; the object side radius of the eighth lens 8 is R81, the image side radius is R82, 555mm≤R81≤595mm, -270mm≤R82≤-255mm; the object side radius of the ninth lens 9 is R91, the image side radius is R92, 190mm≤R91≤200mm, 600mm≤R92≤620mm; the object side radius of the tenth lens 10 is R101, the image side radius is R102, -390mm≤R101≤-370mm, -275mm≤R102≤-260mm; the object side radius of the eleventh lens 11 is R111, and the image side radius is R112, -175mm≤R111≤-160mm, 115mm≤R112≤125mm; the object side radius of the twelfth lens 12 is R121, and the image side radius is R122, -130mm≤R121≤-115mm, -165mm≤R122≤-150mm;The object side radius of the thirteenth lens 13 is R131, and the image side radius is R132, 285mm≤R131≤305mm, -285mm≤R132≤-265mm; the object side radius of the fourteenth lens 14 is R141, and the image side radius is R142, 170mm≤R141≤185mm, -550mm≤R142≤-530mm; the object side radius of the fifteenth lens 15 is R151, and the image side radius is R152, 100mm≤R151≤110mm, -270mm≤R152≤-255mm; the object side radius of the sixteenth lens 16 is R161, and the image side radius is R162, -200mm≤R 161≤-185mm, 335mm≤R162≤355mm; the object side radius of the seventeenth lens 17 is R171, the image side radius is R172, 100mm≤R171≤115mm, 55mm≤R172≤65mm; the object side radius of the eighteenth lens 18 is R181, the image side radius is R182, 65mm≤R181≤75mm, 220mm≤R182≤230mm; the object side radius of the nineteenth lens 19 is R191, the image side radius is R192, 80mm≤R191≤90mm, 115mm≤R192≤125mm; the object side and image side of the twentieth lens 20 are both set as planes. In addition, the zoom ratio of the lithography objective 100 is A, which satisfies: 0.24≤A≤0.26. ;

[0095] Generally speaking, the center thickness of a lens has little effect on its optical performance, but a lens that is too thin may result in insufficient mechanical strength of the lens and easy damage. The thickness of the lens will affect its mechanical strength and durability. At the same time, the thickness of the lens will also affect the weight and cost of the lens. The thickness of the lens will also affect its light transmission efficiency. A lens that is too thick may increase light loss, thereby reducing the imaging quality of the optical system. Considering the size, weight, and imaging effect of the lithography objective 100, the thickness of the second lens 2 is G2, 31mm≤G2≤33mm; the thickness of the third lens 3 is G3, 47mm≤G3≤51mm; the thickness of the fourth lens 4 is G4, 25mm≤G4≤30mm; the thickness of the fifth lens 5 is G5, 7mm≤G5≤10mm; the thickness of the sixth lens 6 is G6, 37mm≤G6≤42mm; the thickness of the seventh lens 7 is G7, 42mm≤G7≤50mm; the thickness of the eighth lens 8 is G8, 10mm≤G8≤13mm; the thickness of the ninth lens 9 is G9, 18mm≤G9≤22mm; the thickness of the tenth lens 10 is G10, 45mm≤G10≤50mm; the thickness of the eleventh lens 11 is G12, 45mm≤G12≤50mm; The thickness of the lens 11 is G11, 20mm≤G11≤23mm; the thickness of the twelfth lens 12 is G12, 18mm≤G12≤23mm; the thickness of the thirteenth lens 13 is G13, 12mm≤G13≤15mm; the thickness of the fourteenth lens 14 is G14, 40mm≤G14≤45mm; the thickness of the fifteenth lens 15 is G15, 22mm≤G15≤25mm; the thickness of the sixteenth lens 16 is G16, 10mm≤G16≤12mm; the thickness of the seventeenth lens 17 is G17, 15mm≤G17≤20mm; the thickness of the eighteenth lens 18 is G18, 14mm≤G18≤20mm; the thickness of the nineteenth lens 19 is G19, 33mm≤G19≤36mm.

[0096] The refractive index has a profound impact on the lithography objective 100, including but not limited to imaging quality, focal length, chromatic aberration, and the design and manufacture of optical components. The refractive index of each lens in the present lithography objective 100 is as follows: the refractive index of the second lens 2 is n2, 1.4≤n2≤1.5; the refractive index of the third lens 3 is n3, 1.45≤n3≤1.55; the refractive index of the fourth lens 4 is n4, 1.6≤n4≤1.65; the refractive index of the fifth lens 5 is n5, 1.4≤n5≤1.5; the refractive index of the sixth lens 6 is n6, 1.45≤n6≤1.55; the refractive index of the seventh lens 7 is n7, 1.6≤n7≤1.65; the refractive index of the eighth lens 8 is n8, 1.45≤n8≤1.55; the refractive index of the ninth lens 9 is n9, 1.45≤n9≤1.55; the refractive index of the tenth lens 10 is n10, 1.45≤n10≤1.55; the refractive index of the eleventh lens 1 The refractive index of the lens 1 is n11, 1.55≤n11≤1.6; the refractive index of the twelfth lens 12 is n12, 1.55≤n12≤1.6; the refractive index of the thirteenth lens 13 is n13, 1.45≤n13≤1.55; the refractive index of the fourteenth lens 14 is n14, 1.45≤n14≤1.55; the refractive index of the fifteenth lens 15 is n15, 1.45≤n15≤1.55; the refractive index of the sixteenth lens 16 is n16, 1.55≤n16≤1.6; the refractive index of the seventeenth lens 17 is n17, 1.4≤n17≤1.5; the refractive index of the eighteenth lens 18 is n18, 1.45≤n18≤1.55; the refractive index of the nineteenth lens 19 is n19, 1.6≤n19≤1.65. The refractive index can be used to selectively control the light of a specific wavelength band. A material with a specific refractive index can be selected so that the material has a higher transmittance for certain wavelengths of light and a higher reflectivity for other wavelengths of light. In this way, selective transmission of light of a specific wavelength band can be achieved. The design wavelength of the lithography objective 100 is set to 360nm to 370nm by setting the refractive index. In addition, the refractive index of the lens is one of the important factors that determine the size of its chromatic aberration. Chromatic aberration is caused by the different refractive indices of light of different wavelengths when passing through the lens, resulting in different colors of light being unable to converge at the same focus at the same time, thereby forming chromatic aberration. In order to improve chromatic aberration, a suitable refractive index is selected, and a lens material with lower dispersion is selected, because the refractive index of these materials varies less with wavelength, thereby reducing chromatic aberration.

[0097] The ratio of the focal length of a single lens to the overall focal length of the lithography objective 100 can reflect the role and importance of the lens in the entire lithography objective 100. If the ratio is large, it indicates that the lens plays a dominant role in the entire lithography objective 100; if the ratio is small, it indicates that the role of the lens in the entire lithography objective 100 is relatively small. In addition, this ratio can also help understand the design and performance of the lithography objective 100. For example, it can be used to predict the focal length, field of view, resolution and other parameters of the lithography objective 100. It should be noted that this ratio does not directly reflect the quality or performance of the lens, because the quality and performance of the lens are also affected by other factors, such as the material, shape, surface treatment, etc. of the lens. Therefore, although this ratio is a useful reference indicator, it should not be used as the only criterion for evaluating lens quality. The focal length of the lithography objective lens 100 is f, the focal length of the second lens 2 is f2, 0.2≤|f2 / f|≤0.4; the focal length of the third lens 3 is f3, 0.1≤|f3 / f|≤0.4; the focal length of the fourth lens 4 is f4, 0.1≤|f4 / f|≤0.3; the focal length of the fifth lens 5 is f5, 0.1≤|f5 / f|≤0.3; the focal length of the sixth lens 6 is The focal length of the seventh lens 7 is f7, 0.4≤|f7 / f|≤0.6; the focal length of the eighth lens 8 is f8, 0.4≤|f8 / f|≤0.6; the focal length of the ninth lens 9 is f9, 0.6≤|f9 / f|≤0.9; the focal length of the tenth lens 10 is f10, 2≤|f10 / f|≤4; the focal length of the eleventh lens 11 is f20, 2≤|f20 / f|≤4; the focal length of the eleventh lens 12 is f30, 0.4≤|f30 / f|≤0.6; the focal length of the eleventh lens 13 is f40, 0.6≤|f40 / f|≤0.9; the focal length of the eleventh lens 14 is f50, 0.6≤|f50 / f|≤0.9; the focal length of the eleventh lens 15 is f60, 2≤|f6 / f|≤4; the focal length of the eleventh lens 16 is f70, 0.4≤|f7 / f|≤0.6 The focal length of the twelfth lens 12 is f12, 1≤|f12 / f|≤3; the focal length of the thirteenth lens 13 is f13, 0.3≤|f13 / f|≤0.6; the focal length of the fourteenth lens 14 is f14, 0.3≤|f14 / f|≤0.6; the focal length of the fifteenth lens 15 is f15, 0.1≤|f1 5 / f|≤0.4; the focal length of the sixteenth lens 16 is f16, 0.2≤|f16 / f|≤0.4; the focal length of the seventeenth lens 17 is f17, 0.3≤|f17 / f|≤0.6; the focal length of the eighteenth lens 18 is f18, 0.2≤|f18 / f|≤0.6; the focal length of the nineteenth lens 19 is f19, 0.3≤|f19 / f|≤0.6.

[0098] The total optical length refers to the distance from the object side of the first lens 1 in the lithography objective 100 to the image plane, while the focal length is the distance from the center of the lithography objective 100 to the focus. In optical design, the ratio of the focal length to the total optical length is crucial to determining the performance of the lithography objective 100. The telephoto ratio is the ratio of the total optical length to the focal length. The longer the focal length of the lithography objective 100 or the shorter the total optical length, the smaller the telephoto ratio, indicating that the lithography objective 100 can achieve a longer focal length with a shorter length. In addition, the ratio of the focal length to the total optical length is also an important indicator for evaluating the performance of an optical system. For example, in some optical systems, the closer the ratio of the focal length to the total optical length is to 1, the better the performance of the optical system. This is because the closer the ratio of the focal length to the total optical length is to 1, the longer the focal length of the optical system, and the longer the focal length of the optical system, the better its imaging quality is usually. Considering the size, focal length and imaging quality of the lithography objective lens 100 , the total length of the lithography objective lens 100 is TTL, 1.2≤TTL / f≤1.5, 1000 mm≤TTL≤1250 mm.

[0099] Since the larger the numerical aperture, the larger the angle range of light that can be received by the lithography objective lens 100, this helps to improve the resolution of the lithography objective lens 100. According to the requirements, the numerical aperture of the lithography objective lens 100 is NA, and NA≥0.24.

[0100] The F number of an optical system, also known as the F number or aperture number, is an important parameter in an optical system, which represents the light-gathering ability and resolution of the optical system. Specifically, the F number is defined as the ratio of the equivalent focal length of the system to the optical aperture, and the reciprocal of the F number is the relative aperture. In practical applications, the smaller the F number, the faster the "speed" of the lens, that is, under the same lighting conditions, a shorter exposure time can be used to obtain an image of the same brightness. In addition, the F number is also closely related to the theoretical resolution and image plane illumination of the optical system. The smaller the F number, the higher the theoretical resolution of the optical system and the stronger the image plane illumination, but the relative aperture, which is the reciprocal of the F number, will increase, thereby increasing the design difficulty. In general, the F number is an important parameter for measuring the performance of an optical system. In order to meet the performance requirements, the aperture number of the lithography objective 100 is F, 1.8≤F≤2.1.

[0101] According to the above characteristics, the exposure field area of ​​the lithography objective lens 100 is greater than or equal to 72 mm×72 mm, and the resolution is less than 780 nm.

[0102] The data of one specific embodiment are given below:

[0103]

[0104]

[0105]

[0106]

[0107] The utility model also provides a lithography device, the lithography device includes a lithography objective lens 100, the lithography objective lens 100 has an object side and an image side correspondingly arranged along an optical axis direction, the lithography objective lens 100 includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, an eleventh lens 11, a twelfth lens 12, a thirteenth lens 13, a fourteenth lens 14, a fifteenth lens 15, a sixteenth lens 16, a seventeenth lens 17, an eighteenth lens 18, a nineteenth lens 19, and a twentieth lens 20 arranged in sequence from the object side to the image side;

[0108] Wherein, the first lens 1 and the 20th lens 20 are set as plane lenses, the second lens 2, the third lens 3, the sixth lens 6, the seventh lens 7, the eighth lens 8, the ninth lens 9, the tenth lens 10, the thirteenth lens 13, the fourteenth lens 14, the fifteenth lens 15, the eighteenth lens 18, and the nineteenth lens 19 have positive focal lengths; the fourth lens 4, the fifth lens 5, the eleventh lens 11, the twelfth lens 12, the sixteenth lens 16, and the seventeenth lens 17 have negative focal lengths; so that the exposure field area of ​​the lithography objective lens 100 is greater than or equal to 72mm×72mm, and the resolution is less than 780nm. The specific structure of the lithography objective lens 100 refers to the above embodiment. Since the lithography device adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0109] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A lithography objective lens, characterized in that: The photolithography objective lens has an object side and an image side correspondingly arranged along the optical axis direction, and the photolithography objective lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, a thirteenth lens, a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens, an eighteenth lens, a nineteenth lens, and a twentieth lens arranged in sequence from the object side to the image side; Among them, the first lens and the twentieth lens are set as plane lenses, the second lens, the third lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens, the eighteenth lens, and the nineteenth lens have positive optical power; the fourth lens, the fifth lens, the eleventh lens, the twelfth lens, the sixteenth lens, and the seventeenth lens have negative optical power; so that the exposure field area of ​​the lithography objective lens is greater than or equal to 72mm×72mm, and the resolution is less than 780nm.

2. The lithography objective lens according to claim 1, characterized in that: The object side surface and the image side surface of the first lens are both set to be planes; The object side surface of the second lens is set to be a plane, and the image side surface has a curvature radius of R22, -135mm≤R22≤-125mm; The object side radius of the third lens is R31, and the image side radius is R32, 80mm≤R31≤85mm, 380mm≤R32≤390mm; The fourth lens has an object side radius of R41 and an image side radius of R42, wherein -3650mm≤R41≤-3600mm, and 45mm≤R42≤55mm; The object side radius of the fifth lens is R51, the image side radius is R52, -76mm≤R51≤-60mm, 1950mm≤R52≤2050mm; The radius of the object side surface of the sixth lens is R61, and the radius of the image side surface is R62, -105mm≤R61≤-95mm, -110mm≤R62≤-93mm; The seventh lens has an object side radius of R71 and an image side radius of R72, 630 mm ≤ R71 ≤ 650 mm, and -400 mm ≤ R72 ≤ -380 mm; The object side radius of the eighth lens is R81, the image side radius is R82, 555mm≤R81≤595mm, -270mm≤R82≤-255mm; The radius of the object side surface of the ninth lens is R91, and the radius of the image side surface is R92, 190mm≤R91≤200mm, 600mm≤R92≤620mm; The object side radius of the tenth lens is R101, the image side radius is R102, -390mm≤R101≤-370mm, -275mm≤R102≤-260mm; The object side radius of the eleventh lens is R111, the image side radius is R112, -175mm≤R111≤-160mm, 115mm≤R112≤125mm; The object side radius of the twelfth lens is R121, and the image side radius is R122, -130mm≤R121≤-115mm, -165mm≤R122≤-150mm; The object side radius of the thirteenth lens is R131, the image side radius is R132, 285mm≤R131≤305mm, -285mm≤R132≤-265mm; The object side radius of the fourteenth lens is R141, the image side radius is R142, 170mm≤R141≤185mm, -550mm≤R142≤-530mm; The object side radius of the fifteenth lens is R151, and the image side radius is R152, 100mm≤R151≤110mm, -270mm≤R152≤-255mm; The object side radius of the sixteenth lens is R161, the image side radius is R162, -200mm≤R161≤-185mm, 335mm≤R162≤355mm; The object side radius of the seventeenth lens is R171, and the image side radius is R172, 100mm≤R171≤115mm, 55mm≤R172≤65mm; The object side radius of the eighteenth lens is R181, the image side radius is R182, 65mm≤R181≤75mm, 220mm≤R182≤230mm; The object side radius of the nineteenth lens is R191, and the image side radius is R192, 80mm≤R191≤90mm, 115mm≤R192≤125mm; The object-side surface and the image-side surface of the 20th lens are both set to be planes.

3. The lithography objective lens according to claim 1, characterized in that: The thickness of the second lens is G2, 31mm≤G2≤33mm; The thickness of the third lens is G3, 47mm≤G3≤51mm; The thickness of the fourth lens is G4, 25mm≤G4≤30mm; The thickness of the fifth lens is G5, 7mm≤G5≤10mm; The thickness of the sixth lens is G6, 37mm≤G6≤42mm; the thickness of the seventh lens is G7, 42mm≤G7≤50mm; the thickness of the eighth lens is G8, 10mm≤G8≤13mm; the thickness of the ninth lens is G9, 18mm≤G9≤22mm; the thickness of the tenth lens is G10, 45mm≤G10≤50mm; the thickness of the eleventh lens is G11, 20mm≤G11≤23mm; the thickness of the twelfth lens is G12, 18mm≤G12≤23mm; the thickness of the thirteenth lens is G13, 18mm≤G14≤23mm; The thickness of the mirror is G13, 12mm≤G13≤15mm; the thickness of the fourteenth lens is G14, 40mm≤G14≤45mm; the thickness of the fifteenth lens is G15, 22mm≤G15≤25mm; the thickness of the sixteenth lens is G16, 10mm≤G16≤12mm; the thickness of the seventeenth lens is G17, 15mm≤G17≤20mm; the thickness of the eighteenth lens is G18, 14mm≤G18≤20mm; the thickness of the nineteenth lens is G19, 33mm≤G19≤36mm.

4. The lithography objective lens according to claim 1, characterized in that: The refractive index of the second lens is n2, 1.4≤n2≤1.5; The refractive index of the third lens is n3, 1.45≤n3≤1.55; The refractive index of the fourth lens is n4, 1.6≤n4≤1.65; The refractive index of the fifth lens is n5, 1.4≤n5≤1.5; The refractive index of the sixth lens is n6, 1.45≤n6≤1.55; The refractive index of the seventh lens is n7, 1.6≤n7≤1.65; The refractive index of the eighth lens is n8, 1.45≤n8≤1.55; The refractive index of the ninth lens is n9, 1.45≤n9≤1.55; The refractive index of the tenth lens is n10, 1.45≤n10≤1.55; The refractive index of the eleventh lens is n11, 1.55≤n11≤1.6; The refractive index of the twelfth lens is n12, 1.55≤n12≤1.6; The refractive index of the thirteenth lens is n13, 1.45≤n13≤1.55; The refractive index of the fourteenth lens is n14, 1.45≤n14≤1.55; The refractive index of the fifteenth lens is n15, 1.45≤n15≤1.55; The refractive index of the sixteenth lens is n16, 1.55≤n16≤1.6; The refractive index of the seventeenth lens is n17, 1.4≤n17≤1.5; The refractive index of the eighteenth lens is n18, 1.45≤n18≤1.55; The refractive index of the nineteenth lens is n19, 1.6≤n19≤1.

65.

5. The lithography objective lens according to claim 1, characterized in that: The focal length of the lithography objective is f, The focal length of the second lens is f2, 0.2≤|f2 / f|≤0.4; The focal length of the third lens is f3, 0.1≤|f3 / f|≤0.4; The focal length of the fourth lens is f4, 0.1≤|f4 / f|≤0.3; The focal length of the fifth lens is f5, 0.1≤|f5 / f|≤0.3; The focal length of the sixth lens is f6, 2≤|f6 / f|≤4; The focal length of the seventh lens is f7, 0.4≤|f7 / f|≤0.6; The focal length of the eighth lens is f8, 0.4≤|f8 / f|≤0.6; The focal length of the ninth lens is f9, 0.6≤|f9 / f|≤0.9; The focal length of the tenth lens is f10, 2≤|f10 / f|≤4; The focal length of the eleventh lens is f11, 0.1≤|f11 / f|≤0.5; The focal length of the twelfth lens is f12, 1≤|f12 / f|≤3; The focal length of the thirteenth lens is f13, 0.3≤|f13 / f|≤0.6; The focal length of the fourteenth lens is f14, 0.3≤|f14 / f|≤0.6; The focal length of the fifteenth lens is f15, 0.1≤|f15 / f|≤0.4; The focal length of the sixteenth lens is f16, 0.2≤|f16 / f|≤0.4; The focal length of the seventeenth lens is f17, 0.3≤|f17 / f|≤0.6; The focal length of the eighteenth lens is f18, 0.2≤|f18 / f|≤0.6; The focal length of the nineteenth lens is f19, 0.3≤|f19 / f|≤0.

6.

6. The lithography objective lens according to claim 5, characterized in that: The total length of the photolithography objective lens is TTL, 1.2≤TTL / f≤1.5, 1000mm≤TTL≤1250mm.

7. The lithography objective lens according to claim 1, characterized in that: The image side numerical aperture of the photolithography objective is NA, and NA≥0.

24.

8. The lithography objective lens according to claim 1, characterized in that: The aperture number of the photolithography objective lens is F, 1.8≤F≤2.

1.

9. The lithography objective lens according to claim 1, characterized in that: The zoom ratio of the lithography objective lens is A, 0.24≤A≤0.

26.

10. A lithography apparatus, characterized in that: It comprises the lithography objective lens as claimed in any one of claims 1 to 9.

Images