Lithographic system and method of manufacturing a lithographic system

Abstract

The application provides a photolithography system and a manufacturing method thereof. The photolithography system comprises a light emitting structure, a holographic mask plate, and a focusing lens group. The focusing lens group is located in the light path from the light emitting structure to the holographic mask plate. The holographic mask plate comprises a holographic pattern. An exposure light beam passing through the holographic pattern is adapted to form a target pattern at the focal plane position of the focusing lens group. The photolithography system has a simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photolithography, in particular to a photolithography system and a manufacturing method thereof. BACKGROUND

[0002] In the field of integrated circuit processing, photolithography plays a crucial role. Photolithography exposure methods have undergone several stages of development in recent years, including contact photolithography, proximity photolithography, and projection photolithography. Projection photolithography exposure methods transfer target patterns to wafers through a projection objective lens. In the ultraviolet band, due to material limitations, the main materials that can be selected for ultraviolet lenses are ultraviolet fused quartz and calcium fluoride. However, calcium fluoride is difficult to process and expensive. Due to material limitations, the projection objective lens has weak chromatic aberration correction capabilities. The number of integrated circuit threads that can be processed by traditional projection exposure photolithography methods is limited by the projection objective lens. To avoid the dependence of conventional projection photolithography on the projection objective lens, existing technologies design complex imaging optical structures in photolithography systems. In particular, at 193 nm, the available deep ultraviolet optical materials are single, difficult to manufacture, and additional projection objective lenses are required to form a complex optical system. Therefore, there is a need to provide a photolithography system and a manufacturing method thereof. SUMMARY

[0003] Therefore, the technical problem to be solved by the present application is to overcome the structural complexity of the photolithography system in the prior art, thereby providing a photolithography system and a manufacturing method thereof.

[0004] The present application provides a photolithography system, comprising: a light emitting structure; a holographic mask plate; a focusing lens group located in the optical path from the light emitting structure to the holographic mask plate; the holographic mask plate contains a holographic pattern, and the exposure light beam passing through the holographic pattern is adapted to form a target pattern at the focal plane position of the focusing lens group.

[0005] Optionally, an expansion collimation unit located in the optical path from the light emitting structure to the focusing lens group; the expansion collimation unit comprises an expansion unit and a collimation unit, the expansion unit is located in the optical path between the light emitting structure and the collimation unit; the expansion unit comprises a first concave lens; the collimation unit comprises a second concave lens and a first convex lens, the second concave lens is located between the expansion unit and the first convex lens, and the focal length of the second concave lens is greater than the focal length of the first concave lens; the focal point of the expansion unit towards the light emitting structure side coincides with the focal point of the collimation unit towards the light emitting structure side.

[0006] Optionally, the focal length of the collimation unit is 290mm-350mm greater than the focal length of the expansion unit.

[0007] Optionally, the focal length of the first convex lens is 160-200 mm, the focal length of the first concave lens is (-5) mm-(-15) mm, and the focal length of the second concave lens is (-320) mm-(-350) mm.

[0008] Optionally, the focusing lens group comprises first to Nth sub-convex lenses arranged in the light path from the light-emitting structure to the holographic mask plate, and a third concave lens located in the light path from the light-emitting structure to the first sub-convex lens, N being an integer equal to or greater than 2; the distance from the holographic mask plate to the center of the side surface of the Nth sub-convex lens towards the holographic mask plate is less than the focal length of the focusing lens group.

[0009] Optionally, the distance from the holographic mask plate to the center of the side surface of the Nth sub-convex lens towards the holographic mask plate is 8-10 mm, and the focal length of the focusing lens group is 22-28 mm.

[0010] Optionally, the system further comprises a mirror adapted to reflect the light emitted from the beam-expanding collimating unit to the focusing lens group.

[0011] The application further provides a method for manufacturing a photolithography system, comprising: forming a holographic mask plate containing a holographic pattern; providing a light-emitting structure and a focusing lens group; placing the holographic mask plate in the light path between the light-emitting structure and the focusing lens group; and forming a target pattern at the focal plane position of the focusing lens group through an exposure light beam passing through the holographic pattern.

[0012] Optionally, the step of forming the holographic mask plate comprises: providing a temporary mask plate having a target pattern therein; arranging a reference light source, the line connecting the center of the reference light source and the geometric center of the temporary mask plate being perpendicular to the thickness direction of the temporary mask plate; and emitting a plane wave using a plane wave light source, the plane wave irradiating the temporary mask plate, the plane wave passing through the target pattern in the temporary mask plate to form transmitted light, the transmitted light and the reference light source interfering to form a holographic pattern at a first position, the distance between the first position and the temporary mask plate being z1. Optionally, the step of forming the holographic mask plate comprises: providing a temporary mask plate having a target pattern therein; arranging a reference light source, the line connecting the center of the reference light source and the geometric center of the temporary mask plate being perpendicular to the thickness direction of the temporary mask plate; and emitting a plane wave using a plane wave light source, the plane wave irradiating the temporary mask plate, the plane wave passing through the target pattern in the temporary mask plate to form transmitted light, the transmitted light and the reference light source interfering to form a holographic pattern at a first position, the distance between the first position and the temporary mask plate being z1. x l is the length dimension of the temporary mask plate in the direction parallel to the line connecting the center of the reference light source and the geometric center of the temporary mask plate, Δx is the distance between the center points of adjacent engraved openings when the holographic pattern is engraved in the initial mask plate, and λ1 is the wavelength of the laser used when the holographic pattern is engraved in the initial mask plate.

[0013] Optionally, the step of forming the holographic pattern comprises:

[0014] obtaining a light field distribution of the transmitted light as u2(x0, y0);

[0015] u2(x0, y0) = u1(x0, y0)t(x0, y0); u1(x0, y0) = A1exp(ikz);

[0016] wherein u1(x0, y0) is a complex amplitude distribution of the plane wave, t(x0, y0) is a transmittance function of the temporary mask, x0 is a horizontal coordinate of a spatial plane where the target pattern is located, the horizontal coordinate of the spatial plane where the target pattern is located is parallel to a line connecting a center of the reference light source and a geometric center of the temporary mask; y0 is a vertical coordinate of the spatial plane where the target pattern is located, A1 is an amplitude of a light beam of the plane wave, i is an imaginary unit, k is a wave number, k = 2π / λ, z is a distance between the plane wave light source and the temporary mask, and λ is a wavelength of the plane wave; and obtaining a light field distribution u3(x, y) of the transmitted light at the first position:

[0017] ; wherein a constant f x is a horizontal coordinate spatial frequency of a plane where the holographic pattern is located, f y is a vertical coordinate spatial frequency of the plane where the holographic pattern is located, z1 is a distance between the temporary mask and the holographic pattern; x is a horizontal coordinate of a spatial plane where the holographic pattern is located, the horizontal coordinate of the spatial plane where the holographic pattern is located is parallel to the line connecting the center of the reference light source and the geometric center of the temporary mask; and y is a vertical coordinate of the spatial plane where the holographic pattern is located, obtaining a complex amplitude distribution r1(x, y) = exp(ikr) of the reference light source at the first position; wherein, a is a distance from the center of the reference light source to the geometric center of the temporary mask; and obtaining a transmittance distribution function of the holographic mask

[0018]

[0019] obtaining a holographic pattern of the holographic mask according to the transmittance distribution function of the holographic mask.

[0020] Optionally, further comprising: disposing a beam expanding collimating unit in the light path from the light emitting structure to the focusing lens group; the beam expanding collimating unit comprises a beam expanding unit and a collimating unit, the beam expanding unit is located in the light path between the light emitting structure and the collimating unit; the beam expanding unit comprises a first concave lens; the collimating unit comprises a second concave lens and a first convex lens, the second concave lens is located between the beam expanding unit and the first convex lens, the focal length of the second concave lens is greater than the focal length of the first concave lens; the focal point of the side of the beam expanding unit towards the light emitting structure coincides with the focal point of the side of the collimating unit towards the light emitting structure.

[0021] Optionally, further comprising: disposing a mirror in the light path from the beam expanding collimating unit to the focusing lens group, the mirror is adapted to reflect the light emitted from the beam expanding collimating unit to the focusing lens group.

[0022] The technical scheme of the present application has the following advantages:

[0023] The light etching system provided by the present application, the holographic mask plate contains a holographic pattern, the exposure light beam of the focusing lens group passing through the holographic pattern is adapted to form a target pattern at the focal plane position of the focusing lens group, the light emitted by the light emitting structure forms a spherical wave through the focusing lens group, and the spherical wave is irradiated on the holographic mask plate to form a target pattern at the focal plane position of the focusing lens group through the holographic display principle, without the need of an additional projection objective lens, and therefore, the structure of the light etching system is simple.

[0024] Further, a beam expanding collimating unit is located in the light path from the light emitting structure to the focusing lens group; the beam expanding collimating unit comprises a beam expanding unit and a collimating unit, the beam expanding unit is located in the light path between the light emitting structure and the collimating unit; the beam expanding unit comprises a first concave lens; the collimating unit comprises a second concave lens and a first convex lens, the second concave lens is located between the beam expanding unit and the first convex lens, the focal length of the second concave lens is greater than the focal length of the first concave lens; the focal point of the side of the beam expanding unit towards the light emitting structure coincides with the focal point of the side of the collimating unit towards the light emitting structure. The beam expanding unit in the beam expanding collimating unit expands the light emitted by the light emitting structure, and the collimating unit in the beam expanding collimating unit collimates the light emitted by the light emitting structure, and therefore, the beam expanding collimating unit can make the light emitting structure irradiate the holographic mask plate in a large area, and improve the light etching efficiency of the light etching system. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without creative work based on these drawings also belong to the protection scope of the present application.

[0026] Figure 1 The structural schematic diagram of the photolithography system provided by an embodiment of the present application;

[0027] Figure 2 The target pattern formed by the exposure light beam passing through the holographic pattern in the photolithography system provided by the embodiment;

[0028] Figure 3 The wavefront aberration diagram of the focusing lens group provided by an embodiment of the present application;

[0029] Figure 4 The flow chart of the manufacturing method of the photolithography system provided by an embodiment of the present application;

[0030] Figure 5 The structural schematic diagram of the process of forming the holographic pattern provided by an embodiment of the present application;

[0031] Figure 6 The target pattern in the temporary mask provided by an embodiment of the present application;

[0032] Figure 7 The holographic pattern formed by the interference of the transmission light and the reference light source at the first position provided by an embodiment of the present application;

[0033] Figure 8 The structural schematic diagram of the reference light source in spherical wave used for forming the holographic pattern provided by an embodiment of the present application;

[0034] Figure 9 The structural schematic diagram of the reference light source in plane wave used for forming the holographic pattern provided by an embodiment of the present application;

[0035] Figure 10 The principle schematic diagram of the holographic pattern reproduction. Specific embodiments

[0036] The technical solutions of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work also belong to the protection scope of the present application.

[0037] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and 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 particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as there is no conflict between them.

[0040] Embodiment 1

[0041] The present embodiment provides a photolithography system, referring to Figure 1 , comprising:

[0042] a light emitting structure 1;

[0043] a holographic mask plate 2;

[0044] a focusing lens group 3 located in the light path from the light emitting structure 1 to the holographic mask plate 2;

[0045] The holographic mask plate 2 contains a holographic pattern, and the exposure light beam passing through the holographic pattern is adapted to form a target pattern at the focal plane position of the focusing lens group 3.

[0046] The photolithography system provided by the present embodiment contains a holographic pattern in the holographic mask plate, and the focusing lens group is adapted to form a target pattern at the focal plane position of the focusing lens group by the exposure light beam passing through the holographic pattern. The light emitted by the light emitting structure forms a spherical wave through the focusing lens group, and the spherical wave is irradiated on the holographic mask plate to form a target pattern at the focal plane position of the focusing lens group by holographic display principle. Therefore, the photolithography system has a simple structure without additional projection objective lens.

[0047] In one embodiment, referring to Figure 2 ,Figure 2 a target pattern formed by the exposure light beam passing through the holographic pattern at a focal plane position of the focusing lens group.

[0048] In one embodiment, the light emitting structure comprises a solid laser, and the light emitting wavelength of the light emitting structure is 180nm-200nm, for example, 193nm.

[0049] In one embodiment, the photolithography system further comprises a beam expanding and collimating unit 4 located in the light path from the light emitting structure 1 to the focusing lens group 3.

[0050] In one embodiment, the beam expanding and collimating unit 4 comprises a beam expanding unit 41 and a collimating unit 42, the beam expanding unit 41 is located in the light path between the light emitting structure 1 and the collimating unit 42; the beam expanding unit 41 comprises a first concave lens; the collimating unit 42 comprises a second concave lens 401 and a first convex lens 402, the second concave lens 401 is located between the beam expanding unit 41 and the first convex lens 402, and the focal length of the second concave lens 401 is greater than that of the first concave lens; the focal point of the beam expanding unit 41 towards the light emitting structure 1 coincides with the focal point of the collimating unit 42 towards the light emitting structure 1. The beam expanding unit 41 in the beam expanding and collimating unit 4 expands the light emitted by the light emitting structure, and the collimating unit 42 in the beam expanding and collimating unit 4 collimates the light emitted by the light emitting structure, so that the beam expanding and collimating unit can make the light emitting structure irradiate the holographic mask plate in a large area, and improve the photolithography efficiency of the photolithography system.

[0051] In one embodiment, the focal length of the collimating unit 42 is greater than the focal length of the beam expanding unit 41 by 290mm-350mm, for example, 300mm.

[0052] In one embodiment, the focal length of the first convex lens 402 is 160mm-200mm, for example, 180mm; the focal length of the first concave lens is (-5)mm-(-15)mm, for example, (-10)mm; and the focal length of the second concave lens 401 is (-320)mm-(-350)mm, for example, (-333)mm.

[0053] In one embodiment, the focusing lens group 3 comprises first to Nth sub-convex lenses arranged at intervals in the light path from the light emitting structure 1 to the holographic mask plate 2, and a third concave lens located in the light path from the light emitting structure to the first sub-convex lens, N is an integer equal to or greater than 2; the distance from the surface center of the holographic mask plate 2 to the Nth sub-convex lens towards the holographic mask plate is less than the focal length of the focusing lens group. Figure 3The focusing lens group comprises several sub-convex lenses, which is beneficial to converging spherical waves and making the wavefront aberration of the spherical waves smaller.

[0054] In one embodiment, the distance from the holographic mask plate to the Nth sub-convex lens to the center of the side surface of the holographic mask plate is 8mm-10mm, and the focal length of the focusing lens group is 22mm-28mm, for example, 25.44mm.

[0055] In one embodiment, the focal length of the third concave lens is (-60)mm-(-65m), for example, -60.14mm.

[0056] In this embodiment, N is taken as an example of five, and in other embodiments, N can also take other integers. In this embodiment, continuing to refer to Figure 1 The focusing lens group 3 comprises first to fifth sub-convex lenses arranged in the light path from the light emitting structure 1 to the holographic mask plate 2, and a third concave lens 31 located in the light path from the light emitting structure to the first sub-convex lens. The focal length of the first sub-convex lens 32 is 180mm-182mm, for example, 181.52mm, the focal length of the second sub-convex lens 33 is 200mm-210mm, for example, 205.01mm, the focal length of the third sub-convex lens 34 is 190mm-195mm, for example, 194.49mm, the focal length of the fourth sub-convex lens 35 is 180mm-185mm, for example, 182.15mm, and the focal length of the fifth sub-convex lens 36 is 125mm-130mm, for example, 128.18mm.

[0057] In one embodiment, the photolithography system further comprises a mirror 5 adapted to reflect the light emitted from the beam expander and collimator unit 4 to the focusing lens group 3.

[0058] In one embodiment, the focal plane of the focusing lens group is adapted to place a wafer 6, and the wafer 6 has a photoresist layer on the side surface facing the focusing lens group.

[0059] Embodiment 2

[0060] This embodiment provides a manufacturing method of a photolithography system, referring to Figure 4 , comprising the following steps:

[0061] Step S1: forming a holographic mask plate, the holographic mask plate comprising a holographic pattern;

[0062] Step S2: providing a light emitting structure and a focusing lens group, and placing the holographic mask plate in the light path between the light emitting structure and the focusing lens group; the exposure beam passing through the holographic pattern is adapted to form a target pattern at the focal plane position of the focusing lens group.

[0063] In one embodiment, the target pattern in the temporary mask 10 is a Figure 5 The step of forming the holographic mask includes:

[0064] A temporary mask 10 is provided, which has a target pattern therein;

[0065] A reference light source 20 is provided, the center line of which is perpendicular to the thickness direction of the temporary mask 10;

[0066] A plane wave light source 30 is used to emit a plane wave, which irradiates the temporary mask 10, and the plane wave transmits through the target pattern in the temporary mask 10 to form transmitted light, which interferes with the reference light source 20 to form a holographic pattern 40 at a first position, the distance between which and the temporary mask being z1;

[0067] An initial mask is provided, and the holographic pattern is inscribed in the initial mask to form a holographic mask;

[0068] Wherein, l x is the length dimension of the temporary mask in the direction parallel to the center line of the reference light source and the geometric center of the temporary mask, Δx is the distance between the center points of adjacent inscribed openings when the holographic pattern is inscribed in the initial mask, and λ1 is the wavelength of the laser used when the holographic pattern is inscribed in the initial mask.

[0069] In one embodiment, the target pattern in the temporary mask 10 is a Figure 6 In other embodiments, the target pattern in the temporary mask can also be other patterns, without limitation.

[0070] In one embodiment, the target pattern in the temporary mask 10 is a Figure 7 , Figure 7 is the holographic pattern formed by the interference of the transmitted light and the reference light source at the first position.

[0071] The step of forming the holographic pattern includes:

[0072] The light field distribution of the transmitted light is obtained as u2(x0, y0);

[0073] u2(x0, y0) = u1(x0, y0) t(x0, y0) (Equation 1)

[0074] u1(x0, y0) = A1exp(ikz) (Equation 2)

[0075] wherein u1(x0, y0) is a complex amplitude distribution of the plane wave, t(x0, y0) is a transmittance function of the temporary mask 10, x0 is a horizontal coordinate of a spatial plane where the target pattern is located, the horizontal coordinate of the spatial plane where the target pattern is located is parallel to a line connecting a center of the reference light source and a geometric center of the temporary mask, y0 is a vertical coordinate of the spatial plane where the target pattern is located, A1 is an amplitude of a light beam of the plane wave, i is an imaginary unit, k is a wave number, k = 2π / λ, z is a distance between the plane wave light source 30 and the temporary mask 10, and λ is a wavelength of the plane wave;

[0076] The light field distribution of the transmitted light at the first position is obtained as u3(x, y):

[0077]

[0078] wherein a constant is f x is a horizontal coordinate space frequency of a plane where the holographic pattern 40 is located, f y is a vertical coordinate space frequency of the plane where the holographic pattern 40 is located, and z1 is a distance between the temporary mask 10 and the holographic pattern 40;

[0079]

[0080] wherein x is a horizontal coordinate of a spatial plane where the holographic pattern 40 is located, the horizontal coordinate of the spatial plane where the holographic pattern is located is parallel to a line connecting the reference light source and the geometric center of the temporary mask, and y is a vertical coordinate of the spatial plane where the holographic pattern 40 is located,

[0081] The complex amplitude distribution of the reference light source 20 at the first position is obtained as r1(x, y),

[0082] r1(x, y) = exp(ikr) (Equation 5)

[0083] wherein a is a distance from a center of the reference light source 20 to a geometric center of the temporary mask 10;

[0084] The transmittance distribution function I(x, y) of the holographic mask is obtained according to the complex amplitude distribution r1(x, y) of the reference light source at the first position and the light field distribution u3(x, y) of the transmitted light at the first position,

[0085]

[0086] The holographic pattern of the holographic mask is obtained according to the transmittance distribution function of the holographic mask.

[0087] In one embodiment, referring to Figure 8 , the reference light source 201 is a spherical wave.

[0088] In another embodiment, referring to Figure 9 , the reference light source 202 is a plane wave.

[0089] Referring to Figure 10 , Figure 10 is a schematic diagram of the principle of holographic image reconstruction, a spherical wave r2(x, y) is used to irradiate a holographic mask plate L1, specifically, a spherical wave r2(x, y) is used to irradiate a holographic image with a transmittance distribution function I(x, y), and the transmission light field P1(x, y) of the spherical wave after passing through the holographic image is:

[0090] P1(x, y) = r2(x, y)I(x, y) (Equation 7)

[0091]

[0092] wherein z2 = z1, z2 is the distance between the target image L2 and the holographic mask plate L1, x is the horizontal coordinate of the space plane where the holographic mask plate L1 is located, and y is the vertical coordinate of the space plane where the holographic mask plate L1 is located; the light field distribution P2(ξ, η) of the transmission light field P1(x, y) after diffraction propagation at z2 is:

[0093]

[0094] wherein ξ is the horizontal coordinate of the space plane where the target image L2 is located; and η is the vertical coordinate of the space plane where the target image L2 is located.

[0095]

[0096] It can be seen from equation (10) that the light field distribution P2(ξ, η) is the Fourier transform of the holographic image, and thus the light field distribution u2(x0, y0) of the holographic image can be reproduced as:

[0097]

[0098] The process of writing the holographic image in the initial mask plate to form a holographic mask plate is discrete and discontinuous, and the imaging resolution of the target image formed by the exposure beam passing through the holographic image can generally be determined by the following equation:

[0099]

[0100] Wherein, λ1 is the wavelength of the laser used when the holographic pattern is engraved in the initial mask, z0 is the distance between the plane where the target pattern is located and the plane where the holographic mask is located, N is the number of engraved openings on the holographic mask, Δx is the distance between the center points of adjacent engraved openings when the holographic pattern is engraved in the initial mask.

[0101] The imaging resolution of the target pattern is related to the recording distance z0 and the number and distance between the center points of adjacent engraved openings used in the holographic mask manufacturing process when the wavelength of the laser is constant. According to the Nyquist sampling theorem, the recording process of the holographic pattern generally needs to satisfy:

[0102]

[0103] Meanwhile, in the holographic pattern reproduction process based on the holographic principle, 0th, ±1st order three parts will appear in the plane where the target pattern is located. In the spherical reference wave off-axis holographic recording method, the separation of 0th, ±1st order needs to satisfy:

[0104] a>1.5l x (Formula 14)

[0105] Wherein, a is the distance from the center of the reference light source to the geometric center of the temporary mask, l x is the size of the temporary mask in the x0 direction.

[0106] Reference Figure 5 , the x0 plane is the plane where the temporary mask is located, the x plane is the plane where the holographic pattern is located, and the distance between the plane where the temporary mask is located and the plane where the holographic pattern is located is z1, wherein l x is the length of the temporary mask in the direction parallel to the line connecting the center of the reference light source and the geometric center of the temporary mask, and the width of the holographic pattern is L x The width direction of the holographic pattern is parallel to the horizontal coordinate of the space plane where the holographic pattern is located, and then the minimum spatial frequency F xmin and the maximum spatial frequency F xmax in the holographic pattern can be calculated.

[0107]

[0108]

[0109] From formula (14), formula (15) and formula (16), it can be seen that the recording distance z1 should satisfy:

[0110]

[0111] The formula (12) and formula (17) reflect the resolution of the hologram under the condition that the number of sampling points, sampling interval and width of the temporary mask are determined. Generally, under the condition that the above values are determined, the spherical reference wave can take a shorter recording distance z1, so that a better resolution can be obtained.

[0112] In one embodiment, the method for manufacturing the photolithography system further comprises: disposing a beam expansion collimation unit in the light path from the light emitting structure to the focusing lens group.

[0113] In one embodiment, the beam expansion collimation unit comprises a concave lens and a convex lens, the focal length of the convex lens is greater than the focal length of the concave lens, the concave lens is located between the light emitting structure and the convex lens, and the focal point of the concave lens towards the light emitting structure side coincides with the focal point of the convex lens towards the light emitting structure side.

[0114] In one embodiment, the method for manufacturing the photolithography system further comprises: disposing a mirror in the light path from the beam expansion collimation unit to the focusing lens group, the mirror is adapted to reflect the light emitted from the beam expansion collimation unit to the focusing lens group.

[0115] Obviously, the above embodiments are only examples for clearly illustrating, but not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to enumerate all the embodiments. The changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A photolithography system, characterized in that, include: Light-emitting structure; Holographic mask template; A focusing lens group, wherein the focusing lens group is located in the optical path from the light-emitting structure to the holographic mask; The holographic mask contains a holographic pattern, and the exposure beam passing through the holographic pattern is adapted to form a spherical wave through the focusing lens group, which illuminates the focal plane position of the focusing lens group to form a target pattern; The focusing lens group includes a first sub-convex lens to an Nth sub-convex lens arranged at intervals in the optical path from the light-emitting structure to the holographic mask, and a third concave lens located in the optical path from the light-emitting structure to the first sub-convex lens, where N is an integer equal to or greater than 2; The distance from the holographic mask to the center of the surface of the Nth sub-convex lens facing the holographic mask is less than the focal length of the focusing lens group; The distance from the center of the surface of the holographic mask to the side of the Nth sub-convex lens facing the holographic mask is 8mm-10mm, and the focal length of the focusing lens group is 22mm-28mm.

2. The photolithography system according to claim 1, characterized in that, A beam-expanding and collimating unit located in the optical path from the light-emitting structure to the focusing lens group; The beam expanding and collimating unit includes a beam expanding unit and a collimating unit, wherein the beam expanding unit is located in the optical path between the light-emitting structure and the collimating unit; The beam expander unit includes a first concave lens; The collimation unit includes a second concave lens and a first convex lens. The second concave lens is located between the beam expanding unit and the first convex lens, and the focal length of the second concave lens is greater than the focal length of the first concave lens. The focal point of the beam expander unit facing the light-emitting structure coincides with the focal point of the collimator unit facing the light-emitting structure.

3. The photolithography system according to claim 2, characterized in that, The focal length of the collimating unit is 290mm-350mm longer than that of the beam expander unit. The focal length of the first convex lens is 160mm-200mm, the focal length of the first concave lens is (-5)mm-(-15)mm, and the focal length of the second concave lens is (-320)mm-(-350)mm.

4. The photolithography system according to claim 2, characterized in that, Also includes: A reflector adapted to reflect light emitted from the beam expanding and collimating unit to the focusing lens group.

Images