Novel mixed hollow-core optical fiber applied to photoetching machine wavelength

Abstract

The invention discloses a novel mixed hollow-core optical fiber applied to photoetching machine wavelength. The novel mixed hollow-core optical fiber is sequentially provided with an outer cladding area, an inner cladding area and an air fiber core area from outside to inside. The outer cladding region is of a photonic band gap type and is formed by periodically arranging same circular air holes; the inner cladding region is of an anti-resonance type and is divided into a non-nested structure and a nested structure, and the non-nested structure comprises a scallop-shaped cladding tube and a first-class circular cladding tube; the nested structure is composed of a second-type circular cladding tube and a circular nested tube; nodes do not exist in all kinds of cladding pipes, the second kind of circular cladding pipes are distributed among the scallop-shaped cladding pipes at equal intervals, and the first kind of circular cladding pipes are distributed between the scallop-shaped cladding pipes and the second kind of circular cladding pipes; each type of cladding tube is internally tangent to and welded with the inner cladding of the optical fiber. The advantages of the photonic band gap type optical fiber and the anti-resonance type optical fiber are combined, the characteristics of ultra-low loss, near-zero dispersion and the like are achieved in the deep ultraviolet band, and the optical fiber can be used for a photoetching machine with the wavelength of 193 nm.

Description

Technical Field

[0001] The present invention relates to the field of deep ultraviolet optical fibers, and in particular to a novel hybrid structure hollow-core optical fiber with low loss and anti-bending properties for use at a wavelength (193 nm) of a photolithography machine. Background Art

[0002] With the rapid development of modern information technology, integrated circuits (ICs) have become the core of the information age. The famous Moore's Law predicts the continuous growth path of integrated circuit performance. However, the continued establishment of Moore's Law is based on the unremitting innovation and progress of integrated circuit manufacturing technology. In the entire integrated circuit manufacturing process, photolithography is the most core and complex process step. This technology uses optical principles to transfer circuit patterns on silicon wafers, which determines the minimum feature size and density of transistors. Therefore, photolithography technology is known as the "Mount Everest of ultra-precision cutting-edge equipment." In order to meet the requirements of advanced processes, it is necessary to continuously improve the resolution of photolithography machines. According to the Rayleigh criterion, the improvement of the resolution of photolithography machines depends on the use of shorter wavelength light sources to achieve smaller chip processes. Around 1999, many companies began to launch photolithography machines using ArF light sources with a wavelength of 193nm, and eventually made the process node reach 130∼65nm. After that, the immersion method based on 193nm wavelength photolithography machines gradually became the mainstream in the industry. In terms of the chip manufacturing technology system, it is necessary not only to support terminal engineering projects, but also to pay attention to details and key technologies, such as deep ultraviolet optical fiber for lithography machines.

[0003] In the ultraviolet band, quartz optical fiber has serious intrinsic defects - ultraviolet photodarkening effect under long-term irradiation, low conductible power and multimode transmission. Therefore, dispersion and nonlinearity are important reasons affecting its slow development, and hollow-core optical fiber is an ideal carrier for ultraviolet light transmission. As the name suggests, hollow-core optical fiber establishes a light-guiding path in the air core to solve the intrinsic material defect problem encountered in optical fiber technology. There are two options for its technical realization: photonic bandgap hollow-core optical fiber and antiresonant hollow-core optical fiber. The former is to arrange different dielectric materials periodically to realize and optimize the coherent decomposition of light fields similar to Bragg reflection. In terms of structure, photonic bandgap hollow-core optical fiber has non-continuous two-dimensional translational symmetry and one-dimensional radial translational symmetry in the cross section of the optical fiber. Antiresonant hollow-core optical fiber is another type of hollow-core light-guiding optical fiber that emphasizes the realization of coherent decomposition of light fields in a local area. It effectively reduces the spatial overlap of the mode field and the glass surface, becoming a high-performance hollow-core optical fiber.

[0004] When traditional UV optical fiber is used in the deep UV region (190-325nm), it is affected by the radiation of the UV light source, and the transmission efficiency is greatly reduced. At the same time, the transmission is extremely unstable, which may cause short-wave failure in a short time. However, there are few hollow-core optical fibers designed for the deep UV region. Generally speaking, the short-wave band restricts the flexibility of hollow-core optical fiber design, which is mainly manifested in the restriction of short-wave on the core size. According to relevant theories, a larger air ratio in hollow-core optical fiber is a favorable way to solve the damage of UV light source radiation to optical fiber materials. However, hollow-core optical fibers optimized for the deep UV band are rarely able to balance the air ratio and beam capacity, and thus cannot effectively solve the inherent optical damage and optical loss problems of UV optical fiber. Summary of the invention

[0005] Purpose of the invention: In view of the problems of optical loss and optical damage inside the core of existing ultraviolet optical fibers caused by ultraviolet radiation, the purpose of the present invention is to provide a new hybrid hollow-core optical fiber for use at the wavelength of a lithography machine, which has low-loss and anti-bending properties.

[0006] Technical solution: To achieve the above-mentioned invention object, the present invention adopts the following technical solution: A novel hybrid hollow-core optical fiber for use at the wavelength of a photolithography machine, wherein the optical fiber is sequentially arranged from the outside to the inside as an outer cladding region, an inner cladding region and an air core region; the outer cladding region is a photonic bandgap type, and is composed of circular air holes arranged periodically at equal intervals, and forms a polygon with the core as the center; the circular air holes in the outer cladding region are kept intact, and no circular air holes are arranged near the inner cladding region; the inner cladding region is an anti-resonance type, and is surrounded by the circular air holes in the outer cladding region, and includes an anti-resonance structure; the anti-resonance structure is divided into a single-layer non-nested structure and a double-layer structure. There are two types of layer nested structures; the single-layer non-nested structure includes a scallop-shaped cladding tube and a first-type circular cladding tube; the double-layer nested structure is composed of a second-type circular cladding tube and a circular nested tube; there are no nodes between the various types of cladding tubes, wherein the second-type circular cladding tubes are evenly distributed between the scallop-shaped cladding tubes, and the first-type circular cladding tubes are distributed between the scallop-shaped cladding tubes and the second-type circular cladding tubes; the scallop-shaped cladding tube and the first-type circular cladding tube are tangent to the inner cladding wall and are welded; the second-type circular cladding tube and the circular nested tube are inscribed, and the inscribed point is in contact and coincides with the inner cladding wall.

[0007] Preferably, the radius of the circular air holes periodically arranged in the outer cladding region is 2-4 μm, and the center distance between the air holes is 4.4-8.8 μm.

[0008] Preferably, the ratio of the radius of the circumscribed circle of the scallop-shaped cladding tube to the radius of the first type of circular cladding tube is 2-3, and the ratio of the radius of the circumscribed circle of the scallop-shaped cladding tube to the radius of the second type of circular cladding tube is 1; the ratio of the radius of the second type of circular cladding tube to the radius of the circular nested tube is 1.5-2.

[0009] Preferably, the anti-resonance structure comprises three scallop-shaped cladding tubes and six first-type circular cladding tubes, wherein the scallop-shaped cladding tubes are 120° apart from each other, and every two first-type circular cladding tubes are symmetrically located on both sides of the scallop-shaped cladding tube; the anti-resonance structure comprises three sets of double-layer nested structures composed of the second-type circular cladding tubes and circular nested tubes, which are 120° apart from each other, and each double-layer nested structure deviates from the scallop-shaped cladding tube by an angle of 60°.

[0010] Preferably, the first type of circular cladding tubes are symmetrically distributed around the scallop-shaped cladding tube, and the angle of deviation from the scallop-shaped cladding tube is 25° to 30°.

[0011] Preferably, the outer cladding region includes four layers of circular air holes, and the outermost layer of air holes forms a hexagon.

[0012] Preferably, the wall thickness of the scallop-shaped cladding tube, the first type circular cladding tube, the second type circular cladding tube and the circular nested tube of the anti-resonance structure is the same and is 0.34469-0.37977 μm.

[0013] Preferably, the base material of the outer cladding region except the periodically arranged circular air holes, and the base material of the scallop-shaped cladding tube, the first type circular cladding tube, the second type circular cladding tube, and the circular nested tube in the inner cladding region are the same, namely, silicon dioxide or high-hydroxyl pure silicon with a refractive index of 1.5729 to 1.5505.

[0014] Preferably, the circular air holes in the outer cladding region, the scallop-shaped cladding tube in the inner cladding region, the internal space surrounded by the first type circular cladding tube, the second type circular cladding tube and the circular nested tube, and the air core region are all filled with air with a refractive index of 1.

[0015] Preferably, the operating wavelength of the optical fiber is at 193 nm.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following advantages: 1. Compared with the existing common hollow-core optical fibers, the present invention combines the advantages of photonic bandgap and antiresonant hollow-core optical fibers, provides more possibilities for adjusting the optical fiber structure, can change the size and spacing of the air holes in the photonic bandgap region, and adjust the shape and size of various cladding tubes in the antiresonant region, optimize the optical fiber structure to achieve lower restrictive loss, near-zero flat dispersion and other characteristics. In addition, the present invention has no related air hole design in the region adjacent to the antiresonant inner cladding while keeping the circular air holes in the photonic bandgap outer cladding intact, which can increase the stability of the antiresonant region and reduce the difficulty of making the optical fiber.

[0017] 2. The present invention only uses common circular nested structures and simple non-nested single-layer structures in design. Therefore, the proposed optical fiber structure is simple and easy to produce and prepare. In addition, the present invention uses non-nested and nested structures in a certain angle arrangement combination in design, so that the core surrounded by the anti-resonance structure is a regular hexagon, which increases the stability of the optical fiber.

[0018] 3. When designing the present invention, the use of a scalloped cladding tube in a non-nested single-layer structure can effectively improve the anti-resonance effect. The top corners of the scalloped cladding tube are chamfered, so that the fusion of the scalloped cladding tube and the inner cladding is easy to achieve and can form a more stable connection.

[0019] 4. Compared with common glass core ultraviolet optical fibers, the present invention greatly reduces light loss and light damage caused by intrinsic material defects because it uses air as the main propagation medium.

[0020] 5. The present invention can use common silica glass without adding other dielectric materials, and the preparation cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the novel hybrid hollow-core optical fiber of the present invention.

[0022] Figure 2 Schematic diagram of the overall structure of the novel hybrid hollow-core optical fiber of the present invention (marked with dimensions).

[0023] Figure 3 It is a local detail enlarged view of the anti-resonant inner cladding region of the present invention.

[0024] Figure 4 The mode field distribution and height expression diagram of the fundamental mode at a wavelength of 193nm provided in an embodiment of the present invention.

[0025] Figure 5 FIG. 4 is a graph showing the relationship between the limiting loss of the fundamental mode and the wavelength according to an embodiment of the present invention.

[0026] Figure 6 FIG. 4 is a graph showing the relationship between the dispersion of the fundamental mode and the wavelength according to an embodiment of the present invention.

[0027] Figure 7 FIG. 4 is a graph showing the relationship between the nonlinear coefficient of the fundamental mode and the wavelength according to an embodiment of the present invention.

[0028] Figure 8 The diagram is a relationship diagram of bending loss versus bending radius when bending in the x-direction and the y-direction at a wavelength of 193 nm provided by an embodiment of the present invention. The two illustrations in the figure are respectively the electric field mode distribution diagrams when bending in the x-direction and the y-direction. DETAILED DESCRIPTION

[0029] The technical scheme in the embodiment of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiment of the present invention. The described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The present invention is described in detail below with reference to the accompanying drawings.

[0031] like Figure 1 and Figure 2 As shown, a new type of hybrid hollow core optical fiber applied to the wavelength of a lithography machine has low loss and anti-bending characteristics. The optical fiber is sequentially arranged from the outside to the inside as a photonic bandgap type outer cladding region, an anti-resonance type inner cladding region and an air core region; from the inside to the outside, it is sequentially arranged as an optical fiber air core 1, a second type of circular cladding tube 2 in the anti-resonance type inner cladding region, a circular nested tube 3, a first type of circular cladding tube 4, a scallop-shaped cladding tube 5, a circular air hole 6 in the photonic bandgap type outer cladding region and a substrate 7.

[0032] The photonic bandgap outer cladding region is composed of circular air holes 6 arranged periodically at equal intervals and forming a polygon with the core as the center; on the premise that the circular air holes 6 in the outer cladding region remain intact, no circular air holes 6 are set near the inner cladding region.

[0033] The air core 1 is an air area, which is surrounded by the antiresonance structure of the antiresonance type inner cladding area, and is the main light-guiding area of ​​the hollow core optical fiber. The antiresonance structure is divided into two types: a single-layer non-nested structure and a double-layer nested structure. The single-layer non-nested structure includes a scallop-shaped cladding tube 5 and a first-type circular cladding tube 4; the double-layer nested structure is composed of a second-type circular cladding tube 2 with a larger aperture and a circular nested tube 3 with a smaller aperture arranged inside it; there are no nodes between the various cladding tubes, the second-type circular cladding tubes 2 are distributed between the scallop-shaped cladding tubes 5 at equal intervals, and the first-type circular cladding tubes 4 are distributed between the scallop-shaped cladding tubes 5 and the second-type circular cladding tubes 2; wherein, the single-layer scallop-shaped cladding tube 5 and the first-type circular cladding tube 4 are inscribed in the antiresonance type inner cladding wall and fused therewith; the second-type circular cladding tube 2 and the circular nested tube 3 are inscribed in and the tangent point is in contact and coincides with the antiresonance type inner cladding wall.

[0034] The wall thickness and other parameters of the cladding tube in the anti-resonance structure need to meet the anti-resonance condition. When the anti-resonance condition is met, the glass wall has the maximum reflection and the minimum transmission, and most of the light can be reflected back into the fiber core, thereby forming an optical waveguide. The various types of cladding tubes in the anti-resonance structure include the first type of circular cladding tube 4, the second type of circular cladding tube 2, the circular nested tube 3, and the scallop-shaped cladding tube 5. The thickness t1 of each type of cladding tube is the same and meets: ; where t1 represents the thickness of the cladding tube, represents the operating wavelength, n1 and n0 are the refractive index of the cladding tube material and the refractive index of air respectively, and m is a positive integer. In some embodiments, m can be selected as 5.

[0035] In some embodiments, the thickness of the scallop-shaped cladding tube 5 , the first type of circular cladding tube 4 , the second type of circular cladding tube 2 and the circular nested tube 3 of the anti-resonance structure may be set to 0.34469-0.37977 μm.

[0036] In some embodiments, the anti-resonance structure includes three scallop-shaped cladding tubes 5 and six first-type circular cladding tubes 4, wherein each scallop-shaped cladding tube 5 is 120° apart from each other, and every two first-type circular cladding tubes 4 are symmetrically located on both sides of the scallop-shaped cladding tube 5; there are three sets of double-layer nested structures composed of the second-type circular cladding tube 2 and the circular nested tube 3, which are 120° apart from each other, and each double-layer nested structure deviates from the scallop-shaped cladding tube 5 by an angle of 60°. Preferably, the first-type circular cladding tubes 4 are symmetrically distributed with the scallop-shaped cladding tube 5 as the center, and are arranged biased toward the scallop-shaped cladding tube 5, and the angle of deviation from the scallop-shaped cladding tube 5 is 25° to 30° In some embodiments, the ratio of the radius of the circumscribed circle of the scallop-shaped cladding tube 5 to the radius of the first type of circular cladding tube 4 is 2 to 3, and the ratio of the radius of the circumscribed circle of the scallop-shaped cladding tube 5 to the radius of the second type of circular cladding tube 2 is 1. The ratio of the radius of the second type of circular cladding tube 2 to the radius of the circular nested tube 3 is 1.5 to 2. Preferably, the size of each cladding tube can be adjusted within the following range for the wavelength of the lithography machine: the radius of the circumscribed circle of the scallop-shaped cladding tube 5 is 9 to 10 μm, and the radius of the first type of circular cladding tube 4 is 3 to 4 μm. The radius of the second type of circular cladding tube 2 is 9 to 10 μm, and the radius of the circular nested tube 3 is 4 to 5 μm.

[0037] The air core 1 is essentially an air hole surrounded by cladding tubes, and the diameter of the circular air core is 20-22 μm.

[0038] In some embodiments, the radius of the circular air holes 6 arranged periodically in the outer cladding region is 2-4 μm, and the center distance between the air holes 6 is 4.4-8.8 μm. The outer cladding region includes four layers of circular air holes 6, and the outermost layer of air holes 6 forms a hexagon.

[0039] In some embodiments, the base material of the photonic bandgap outer cladding region except the circular air hole 6, the scallop-shaped cladding tube 5 of the antiresonance region, the first type of circular cladding tube 4, the second type of circular cladding tube 2, and the circular nested tube 3 are all made of silicon dioxide with a refractive index of 1.5729 to 1.5505. The material can also be high-hydroxyl pure silicon, etc.

[0040] In some embodiments, the circular air hole 6 in the photonic band gap region, the scallop-shaped cladding tube 5 in the antiresonance region, the first type circular cladding tube 4, the internal space between the second type circular cladding tube 2 and the circular nested tube 3, and the air core region are all filled with air with a refractive index of 1.

[0041] The present invention illustrates the design advantages of the present application through the following embodiments: This embodiment is exemplified by a new type of hybrid hollow core optical fiber applied to the wavelength of a lithography machine (193 nm). The overall structure diagram is shown in Figure 1 and Figure 2 , including an air core 1, a second type of circular cladding tube 2, a circular nested tube 3, a first type of circular cladding tube 4, a scallop-shaped cladding tube 5, a circular air hole 6 in a photon bandgap outer cladding region, and a substrate 7 in a photon bandgap outer cladding region. The photon bandgap outer cladding region substrate 7 is cylindrical, made of silicon dioxide, and has a radius R1 of 75 μm; the radius R2 of the antiresonance inner cladding region is 30 μm, and the radius R3 of the air core 1 is 11 μm; the radius c of the circular air hole 6 in the photon bandgap outer cladding region is 3 μm, and the center distance e between the circular air holes 6 is 6.6 μm.

[0042] like Figure 3 As shown, it is a local enlarged detail view of the anti-resonance inner cladding area. The non-nested structure is composed of the first type of circular cladding tube 4 and the scallop-shaped cladding tube 5, and is inscribed in the inner wall of the anti-resonance inner cladding; the nested structure is composed of the circular nested tube 3 tangent to the second type of circular cladding tube 2, and the inscribed point is fused with the inner wall of the anti-resonance cladding; the thickness t1 of the above-mentioned various types of cladding tubes is the same; the radius r1 of the circumscribed circle of the scallop-shaped cladding tube 5 is 9.5μm, the radius r2 of the rounded corner of the top of the scallop-shaped cladding tube 5 is 2μm, the radius r5 of the first type of circular cladding tube 4 is 3.42μm, the radius r3 of the second type of circular cladding tube 2 is 9.5μm, and the radius r4 of the circular nested tube 3 is 4.75μm. The vertex angle θ1 of the scalloped cladding tube 5 is 60°, the nested structure formed by the second type circular cladding tube 2 and the circular nested tube 3 deviates from the scalloped cladding tube 5 by an angle θ2 of 60°, and the angle θ3 of the first type circular cladding tube 4 deviates from the scalloped cladding tube 5 by 25°.

[0043] The base material of the photonic bandgap outer cladding region and the materials of various types of antiresonant inner cladding tubes are all selected as silicon dioxide; the circular air holes 6 in the photonic bandgap outer cladding region, the scallop-shaped cladding tubes 5 in the antiresonant region, the first type of circular cladding tubes 4, the area between the second type of circular cladding tubes 2 and the circular nested tubes 3, and the internal space of the air core region are all filled with air.

[0044] The present invention uses finite element simulation software COMSOL Multiphysics to simulate and test the present embodiment, and uses the finite element method and combines the perfect matching layer boundary absorption condition to perform theoretical calculations. The mode field distribution diagram, limiting loss, dispersion, and nonlinear coefficient of the present invention are calculated to obtain the relationship diagram of the change of wavelength, and the relationship diagram of the change of bending loss of the present invention with the bending radius is also obtained.

[0045] Figure 4 1 is a diagram showing the mode field distribution and height expression of the fundamental mode at a wavelength of 193 nm. Figure 4 As shown, the novel hybrid structure hollow core optical fiber of the embodiment can concentrate the energy of light waves in the core region when transmitting light, indicating that the present invention can well confine light in the air core region.

[0046] Figure 5 FIG. 4 is a graph showing the relationship between the limiting loss of the fundamental mode of the embodiment and the wavelength. Figure 5 As shown in FIG. 1 , the limiting loss of the embodiment is at a low level when the incident wavelength is 187 nm to 198 nm, and is approximately stable at 2×10 -7 ~1.4×10 -6 It can be seen that the present invention has a lower limiting loss at a wavelength of 193nm.

[0047] Figure 6 is the dispersion of the fundamental mode of the embodiment at the corresponding wavelength. Figure 6 As shown in FIG. 1 , the hybrid hollow-core optical fiber constructed in this embodiment exhibits near-zero dispersion characteristics in the deep ultraviolet band of 187 to 198 nm, and the value of its group velocity dispersion is stable at 2×10 -5 ~-1×10 -5 ps·nm -1 km -1 According to the fiber dispersion theory, dispersion will cause the optical signal to generate pulse broadening problems during fiber transmission due to different propagation speeds, which will affect the quality of fiber communication. Therefore, the closer the dispersion is to zero, the higher the transmission quality of the fiber.

[0048] Figure 7 : is a graph showing the relationship between the nonlinear coefficient of the base film of the embodiment and the wavelength, such as Figure 7 As shown, the nonlinear coefficient of the hybrid hollow-core optical fiber constructed in this embodiment is extremely low in the deep ultraviolet band of 187-198 nm, and the corresponding value is stable at 0.0048-0.00508 W. -1 km -1According to relevant theories, in a high-intensity electromagnetic field, the effect of any medium on light will become nonlinear. Since the core of the optical fiber is small, the field strength inside the core is very high. When the transmission distance is long, the nonlinear effect in the optical fiber will accumulate to a certain intensity and seriously interfere with the signal, while limiting the transmission performance of the system. Therefore, an extremely low nonlinear coefficient means that the optical fiber is less affected by nonlinear effects such as the four-wave mixing effect during the transmission of light.

[0049] Figure 8 FIG. 1 is a graph showing the relationship between the bending loss and the bending radius of an embodiment. Figure 8 As shown in FIG. 1 , the hollow-core antiresonant optical fiber constructed in this embodiment has low bending losses when bending in the x-direction and the y-direction under the condition of a transmission wavelength of 193 nm. When the bending radius is 4 cm, the bending losses of the optical fiber when bending in the x-direction and the y-direction reach 10 -7 dB / km level; when the bending radius is 6 cm, the bending loss of the optical fiber when bending in the x direction and in the y direction is 10 -8 dB / km level, and the bending loss is stable at 10 when the bending radius is 10cm -8 The dB / km level indicates that this embodiment has good anti-bending performance.

[0050] In summary, the hybrid structure hollow-core optical fiber provided by the present invention combines the advantages of photonic bandgap type and anti-resonant type optical fiber, combines the photonic bandgap optical fiber with anti-bending characteristics with the anti-resonant type hollow-core optical fiber with low loss characteristics, increases the proportion of air, and improves the design of optical fiber characteristics by adjusting the anti-resonant structure. The design is a new hybrid hollow-core optical fiber applied to the wavelength of the lithography machine, which can optimize the optical fiber performance in the deep ultraviolet light band, improve the transmission efficiency of light, and achieve ultra-low loss, near-zero dispersion, extremely low nonlinear coefficient and anti-bending characteristics in the deep ultraviolet band, and is easy to implement. The optical fiber designed by the present invention has a high damage threshold and good beam quality, and can play an important role in applications such as ultraviolet light sources, ion trap manipulation, phototherapy and photocatalysis.

[0051] The basic principle, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed for protection.

Claims

1. A new type of hybrid hollow core optical fiber for lithography wavelength, characterized by: The optical fiber is sequentially arranged from outside to inside as an outer cladding region, an inner cladding region and an air core region; The outer cladding region is of photon bandgap type, consisting of circular air holes arranged periodically at equal intervals, and forming a polygon with the core as the center; the circular air holes in the outer cladding region are kept intact, and no circular air holes are arranged near the inner cladding region; The inner cladding region is of antiresonant type, surrounded by circular air holes in the outer cladding region, and comprises an antiresonant structure; the antiresonant structure is divided into two types: a single-layer non-nested structure and a double-layer nested structure; the single-layer non-nested structure comprises a scallop-shaped cladding tube and a first type of circular cladding tube; the double-layer nested structure is composed of a second type of circular cladding tube and a circular nested tube; there are no nodes between the various types of cladding tubes, wherein the second type of circular cladding tubes are evenly spaced between the scallop-shaped cladding tubes, and the first type of circular cladding tubes are distributed between the scallop-shaped cladding tubes and the second type of circular cladding tubes; the scallop-shaped cladding tube and the first type of circular cladding tube are tangent to the inner cladding wall and are fused; the second type of circular cladding tube and the circular nested tube are inscribed, and the inscribed point is in contact and overlaps with the inner cladding wall.

2. The novel hybrid hollow-core optical fiber for lithography wavelength according to claim 1 is characterized in that: The radius of the circular air holes arranged periodically in the outer cladding region is 2-4 μm, and the center distance between the air holes is 4.4-8.8 μm.

3. The novel hybrid hollow-core optical fiber for lithography wavelength according to claim 1 is characterized in that: The ratio of the radius of the circumscribed circle of the scallop-shaped cladding tube to the radius of the first type of circular cladding tube is 2-3, and the ratio of the radius of the scallop-shaped cladding tube to the radius of the second type of circular cladding tube is 1; the ratio of the radius of the second type of circular cladding tube to the radius of the circular nested tube is 1.5-2.

4. The novel hybrid hollow-core optical fiber for lithography wavelength according to claim 1, characterized in that: The anti-resonance structure comprises three scallop-shaped cladding tubes and six first-type circular cladding tubes, wherein the scallop-shaped cladding tubes are 120° apart from each other, and every two first-type circular cladding tubes are symmetrically located on both sides of the scallop-shaped cladding tube; the anti-resonance structure comprises three sets of double-layer nested structures composed of the second-type circular cladding tubes and circular nested tubes, which are 120° apart from each other, and each double-layer nested structure deviates from the scallop-shaped cladding tube by an angle of 60°.

5. The novel hybrid hollow-core optical fiber for lithography wavelength according to claim 1, characterized in that: The first type of circular cladding tubes are symmetrically distributed around the scallop-shaped cladding tube, and the angle of deviation from the scallop-shaped cladding tube is 25° to 30°.

6. The novel hybrid hollow-core optical fiber for use with lithography machine wavelengths according to claim 1, characterized in that: The outer cladding region includes four layers of circular air holes, and the air holes in the outermost layer are surrounded by a hexagon.

7. The novel hybrid hollow-core optical fiber for use with lithography machine wavelengths according to claim 1, characterized in that: The wall thickness of the scallop-shaped cladding tube, the first type circular cladding tube, the second type circular cladding tube and the circular nested tube of the anti-resonance structure is the same and is 0.34469-0.37977 μm.

8. The novel hybrid hollow-core optical fiber for use with lithography machine wavelengths according to claim 1, characterized in that: The base material of the outer cladding region except the periodically arranged circular air holes, and the base material of the scallop-shaped cladding tube, the first type circular cladding tube, the second type circular cladding tube, and the circular nested tube in the inner cladding region are the same, namely, silicon dioxide or high-hydroxyl pure silicon with a refractive index of 1.5729 to 1.5505.

9. The novel hybrid hollow-core optical fiber for lithography wavelength according to claim 1, characterized in that: The circular air holes in the outer cladding region, the internal space surrounded by the scallop-shaped cladding tube in the inner cladding region, the first type of circular cladding tube, the second type of circular cladding tube and the circular nested tube, and the air core region are all filled with air with a refractive index of 1.

10. The novel hybrid hollow-core optical fiber for use with lithography wavelengths according to claim 1, characterized in that: The working wavelength of the optical fiber is at 193 nm.

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