Exposure system and lithography machine

Abstract

The application discloses an exposure system and a photoetching machine. The exposure system comprises a light source, a micromirror array and a microlens array. The light source is used for emitting light. The micromirror array is used for receiving the light and converting the light into a first light spot array. The microlens array and the light source are respectively located on opposite sides of the micromirror array. The microlens array is used for receiving the first light spot array and performing focusing processing on the first light spot array to form a second light spot array. The microlens array projects the second light spot array onto a substrate. The photoetching machine comprises the exposure system. The micromirror array performs patterning processing on all the light and forms the first light spot array. The microlens array performs focusing processing on the first light spot array to form the second light spot array. Each microlens in the microlens array corresponds to each micromirror in the micromirror array. Compared with a traditional exposure system, the alignment accuracy problem between the microlens array and the DMD micromirror does not need to be considered.

Description

Technical Field

[0001] The present invention relates to the technical field of photolithography machines, and in particular to an exposure system and a photolithography machine. Background Art

[0002] Laser direct writing lithography machines are used for the manufacture of integrated circuits, etc. They have good adaptability and flexibility, and relatively lower processing costs. They occupy a very high market share in the circuit board industry, mask plate manufacturing industry, etc.

[0003] However, the laser spot is relatively large, resulting in poor exposure accuracy, which makes it difficult for laser direct writing lithography machines to play their advantages in industries with high precision requirements such as integrated circuit manufacturing. Summary of the Invention

[0004] Based on this, it is necessary to provide an exposure system and a photolithography machine; the exposure system further focuses and reduces the first light spot array formed by the micromirror array into a second light spot array through the setting of a microlens array, and each microlens in the microlens array corresponds one-to-one to each micromirror in the micromirror array. Compared with the traditional exposure system, not only does it not need to consider the alignment problem between the microlens array and the DMD micromirror, but it also avoids the distortion caused by the increase in light spot size due to insufficient alignment accuracy and the impact on the photolithography resolution. The photolithography machine adopts the aforementioned exposure system to ensure the photolithography resolution.

[0005] The technical solution is as follows:

[0006] One embodiment provides an exposure system, comprising:

[0007] a light source, the light source being configured to emit light;

[0008] a micromirror array, the micromirror array being configured to receive the light and convert the light into a first light spot array;

[0009] A microlens array, wherein the microlens array and the light source are respectively located on opposite sides of the micromirror array, the microlens array is used to receive the first light spot array and focus the first light spot array to form a second light spot array, and the microlens array projects the second light spot array onto the substrate.

[0010] In the above-mentioned exposure system, the light source emits light toward the micromirror array, which patterns all the light and forms a first light spot array. The microlens array can further focus the first light spot array into a second light spot array. Each microlens in the microlens array corresponds one-to-one to each micromirror in the micromirror array, eliminating the need to consider the alignment accuracy between the microlens array and the DMD micromirror. At the same time, the problem of reduced lithography resolution due to poor alignment accuracy is avoided.

[0011] The technical solutions are further described below.

[0012] In one of the embodiments, the microlens array comprises a light-transmitting piece and a light-sensitive piece arranged on the light-transmitting piece, the light-sensitive piece is made of a light-sensitive material; the light-sensitive piece forms the microlens array under the irradiation of the first light spot array.

[0013] In one of the embodiments, the light-transmitting piece is a light-transmitting lens, and the light-sensitive piece is a light-sensitive coating arranged on the light-transmitting lens.

[0014] In one of the embodiments, the light-transmitting piece is a light-transmitting lens, and two light-transmitting lenses are arranged, and the light-sensitive piece is arranged between the two light-transmitting lenses.

[0015] In one of the embodiments, the light-sensitive piece is a photopolymer monomer; or the material of the light-sensitive piece is a photorefractive material.

[0016] In one of the embodiments, the exposure system further comprises a first lens group, the first lens group is arranged between the micromirror array and the microlens array, and the first lens group is used for reducing the first light spot array.

[0017] In one of the embodiments, the exposure system further comprises a second lens group, the second lens group is arranged between the microlens array and the substrate.

[0018] In one of the embodiments, the micromirror array is a digital micromirror array; the exposure system further comprises a beam expander assembly, the beam expander assembly is arranged between the light source and the micromirror array.

[0019] In one of the embodiments, the exposure system further comprises a light homogenizing assembly, the light homogenizing assembly is arranged between the light source and the micromirror array.

[0020] Another embodiment provides a photolithography machine, which comprises the exposure system according to any one of the above technical solutions.

[0021] The photolithography machine adopts the exposure system as described above, avoids the problems of large spot size and distortion caused by insufficient alignment between the microlens array and the DMD micromirror, and thus ensures the photolithography resolution. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments of the application illustrated in the drawings are provided to explain the present application and are not meant to limit the present application.

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] In addition, the drawings are not drawn to a 1:1 scale, and the relative sizes of various elements are drawn only as examples in the drawings and are not necessarily drawn to true scale.

[0025] Figure 1 Schematic diagram of an exposure system according to a first embodiment of the present invention;

[0026] Figure 2 Schematic diagram of an exposure system according to a second embodiment of the present invention;

[0027] Figure 3 FIG. 1 is a schematic diagram of an exposure system according to a third embodiment of the present invention.

[0028] Description of the accompanying drawings:

[0029] 100, light source; 200, micromirror array; 300, microlens array; 400, substrate; 500, first lens group; 600, second lens group; 700, beam expansion component and light homogenization component. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below with reference to the accompanying drawings:

[0031] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Please refer to Figures 1 to 3 One embodiment provides an exposure system, including a light source 100 , a micromirror array 200 , and a microlens array 300 , wherein the micromirror array 200 is located between the light source 100 and the microlens array 300 .

[0033] in:

[0034] like Figures 1 to 3 As shown, the light source 100 is used to emit light.

[0035] like Figures 1 to 3In the illustrated embodiment, the light source 100 can emit light according to photolithography requirements, and the light is emitted toward the micromirror array 200 .

[0036] like Figures 1 to 3 As shown, the micromirror array 200 is used to receive the light and perform patterning on the light to form a first light spot array.

[0037] like Figures 1 to 3 In the illustrated embodiment, light emitted by the light source 100 reaches the micromirror array 200 , which then patterns the light and forms a first light spot array.

[0038] like Figures 1 to 3 As shown, the microlens array 300 and the light source 100 are respectively located on opposite sides of the micromirror array 200 . The microlens array 300 is used to receive the first light spot array and focus the first light spot array to form a second light spot array, and project it onto the substrate 400 .

[0039] like Figure 1 In the illustrated embodiment, a light source 100, a micromirror array 200, a microlens array 300, and a substrate 400 are sequentially arranged. The light source 100 emits light toward the micromirror array 200. The micromirror array 200 performs patterning on the incoming light to form a first light spot array. The first light spot array is then focused by the microlens array 300 to form a second light spot array with a smaller spot size. The second light spot array is then projected onto the substrate 400, thereby performing a photolithography operation.

[0040] It should be noted that:

[0041] The first light spot array and the second light spot array here can both be understood as pattern light. Pattern light is a popular name used by those skilled in the art to refer to the light spot array formed after the micromirror array 200 is converted. The meaning of pattern light is well known to those skilled in the art and will not be repeated here.

[0042] Optionally, photoresist is loaded on the substrate 400 to facilitate photolithography processing of the substrate 400 .

[0043] While traditional exposure systems can reduce the spot diameter to 1μm-5μm, this typically requires aligning each microlens array with each DMD micromirror. Misalignment can result in larger spot sizes and distortion, making it difficult to maintain photolithography resolution. Therefore, traditional exposure systems place extremely high demands on the alignment accuracy of the microlens array and DMD micromirrors. Maintaining this alignment accuracy is a significant challenge in traditional exposure systems.

[0044] The exposure system mentioned in the application, the light source 100 emits light towards the micromirror array 200, the micromirror array 200 performs graphical processing on the light and forms a first light spot array, and the microlens array 300 can further focus the first light spot array into a second light spot array. Each microlens in the microlens array 300 corresponds to each micromirror in the micromirror array 200. Compared with the traditional exposure system, the alignment accuracy problem between the microlens array and the DMD micromirror does not need to be considered, and the problem of reduced photolithography resolution caused by poor alignment accuracy is also avoided.

[0045] In one embodiment, the microlens array 300 comprises a light-transmitting piece and a photosensitive piece arranged on the light-transmitting piece, and the photosensitive piece is made of photosensitive material; and the photosensitive piece forms the microlens array under the irradiation of the first light spot array.

[0046] Through the arrangement of the light-transmitting piece and the photosensitive piece, the microlens array 300 can be generated in situ and focus the first light spot array.

[0047] It should be noted that:

[0048] The photosensitive piece generates the microlens array 300 under the first irradiation of the first light spot array, and this process only occurs once.

[0049] After the microlens array 300 is generated, when the first light spot array reaches the microlens array, the microlens array further focuses the first light spot array into a second light spot array with smaller light spot size, and each microlens in the microlens array 300 corresponds to each micromirror in the micromirror array 200, so that the alignment problem in the traditional exposure system does not need to be considered.

[0050] It should be noted that:

[0051] The photosensitive material is a material sensitive to light, including photochromic material, photopolymerization material, photolysis material, photorefractive material, etc.

[0052] In one embodiment, the light-transmitting piece is a light-transmitting lens, and the photosensitive piece is a photosensitive coating arranged on the light-transmitting lens.

[0053] In this embodiment, the light-transmitting piece is an optical light-transmitting lens, and the photosensitive piece is a photosensitive coating formed by coating the photosensitive material on the light-transmitting lens, so that the photosensitive coating generates the microlens array 300 when it is first irradiated by the first light spot array.

[0054] Optionally, the photosensitive material is spin-coated on the light-transmitting lens to form the photosensitive coating.

[0055] Optionally, the light-transmitting piece can be light-transmitting glass, and the photosensitive material is spin-coated on the light-transmitting glass.

[0056] It should be noted that:

[0057] Spin coating (or spin coating) is a coating process that relies on the centrifugal force and gravity generated by the rotation of the workpiece to spread the paint droplets that fall on the workpiece all over the surface of the workpiece.

[0058] In another embodiment, the light-transmitting element is a light-transmitting lens, two light-transmitting lenses are provided, and the photosensitive element is provided between the two light-transmitting lenses.

[0059] In this embodiment, the light-transmitting element is also a light-transmitting lens. However, unlike the previous embodiment, there are two light-transmitting lenses, which are stacked, and the photosensitive element is sandwiched between the two light-transmitting lenses.

[0060] Optionally, the photosensitive element is a photosensitive material encapsulated between two light-transmitting lenses.

[0061] In one embodiment, the photosensitive element is a photopolymerizable monomer.

[0062] Photopolymerization refers to the process of polymerizing monomers using a photochemical reaction. Monomers can be directly stimulated by light to polymerize, or they can be stimulated by photosensitizers or photoinitiators.

[0063] In another embodiment, the photosensitive element is made of a photorefractive material.

[0064] Photorefractive materials refer to materials that can undergo chemical reactions or physical changes under the action of light, resulting in changes in refractive index.

[0065] In one embodiment, please refer to Figure 2 and Figure 3 The exposure system further includes a first lens group 500, which is disposed between the micromirror array 200 and the microlens array 300. The first lens group 500 is used to reduce the size of the first light spot array.

[0066] Different from Figure 1 The embodiment shown, Figure 2 and Figure 3 The illustrated embodiment further includes a first lens group 500, which is located between the micromirror array 200 and the microlens array 300. After light forms a patterned light spot (i.e., a first light spot array) on the micromirror array 200, the first light spot array further reaches the first lens group 500, which further reduces the light spot of the first light spot array.

[0067] In a specific arrangement, the microlens array 300 is disposed at a position corresponding to the imaging position of the first lens group 500. For example, the microlens array 300 is placed at the imaging position of the first lens group 500.

[0068] After the light passes through the micromirror array 200 and the first lens group 500 , a micron-scale light spot array is formed on the microlens array 300 .

[0069] It is understandable that:

[0070] The light spots of the first light spot array obtained after the micromirror array 200 performs patterning processing on the light are also in the micron level. The first lens group 500 further reduces the light spots of the first light spot array to the micron level, which means that the size of the light spots is further reduced at the micron level, such as from 10 to 2, which will not be repeated here.

[0071] In one embodiment, please refer to Figure 3 The exposure system further includes a second lens group 600 , which is disposed between the microlens array 300 and the substrate 400 .

[0072] Different from Figure 1 and Figure 2 The embodiment shown, Figure 3 In the illustrated embodiment, the exposure system includes not only a first lens group 500 but also a second lens group 600, and the first lens group 500 and the second lens group 600 are respectively located on opposite sides of the microlens array 300, and the second lens group 600 is located between the substrate 400 and the microlens array 300.

[0073] The second lens group 600 is provided to enlarge the physical distance between the microlens array and the substrate 400 to prevent the substrate 400 and the microlens array 300 from being too close to each other, thereby causing friction between the substrate 400 and the microlens array 300 and causing wear of the microlens array 300.

[0074] In one embodiment, please refer to Figures 1 to 3 , the micromirror array 200 is a digital micromirror array.

[0075] like Figures 1 to 3 In the illustrated embodiment, the first microlens array is a digital lens array, also known as a DMD micromirror or digital micromirror device (DMD). A DMD is a device based on semiconductor manufacturing technology, consisting of an array of high-speed digital optical reflective switches. It determines the image pattern and its characteristics by controlling the rotation of micromirrors around a fixed axis (yoke) and the time-domain response (which determines the reflection angle and dwell time of light).

[0076] DMD is a new type of fully digital flat panel display device that uses MEMS (Micro Electromechanical System) technology to integrate a reflective micromirror array and CMOS SRAM on the same chip.

[0077] In one embodiment, the exposure system further includes a beam expansion component, which is disposed between the light source 100 and the micromirror array 200 .

[0078] It is understandable that:

[0079] The function of the beam expander is to expand the light spot formed by the light source 100 so as to further emit the light in the direction of the micromirror array 200 .

[0080] In one embodiment, the beam expansion assembly includes a beam expander for expanding the diameter of a parallel input beam to a larger parallel output beam.

[0081] In one embodiment, the exposure system further includes a light homogenization component, which is disposed between the light source 100 and the micromirror array 200 .

[0082] The light homogenizing component can be a light homogenizing sheet or a light homogenizing mirror.

[0083] It is understandable that:

[0084] The function of the light uniformity component is to make the brightness of the light spot formed by the light emitted by the light source 100 uniform. For example, one part of the light spot area is brighter and the other part of the light spot area is darker. The function of the light uniformity component is to adjust the brightness of the entire light spot to a roughly equal brightness, which will not be repeated here.

[0085] In one embodiment, please refer to Figure 2 and Figure 3 The beam expansion component and the light homogenizing component 700 are both arranged between the light source 100 and the micromirror array 200, and the beam expansion component and the light homogenizing component 700 can be integrated.

[0086] After the light source 100 emits light, the light first reaches the beam expander. After passing through the beam expander, the light spot is expanded. Then, the expanded light spot passes through the light homogenizer, which adjusts the brightness of the light spot so that the brightness of the entire light spot is roughly the same. Then, the light spots with roughly the same brightness reach the micromirror array 200, which patterns these light spots and forms a first light spot array, and emits them toward the first lens group 500. The first lens group 500 further reduces the size of the first light spot array to form a micron-level light spot array. The microlens array 300 receives the received light spot array and emits it toward the microlens array 300; the microlens array 300 further reduces the received light spot array to form a second light spot array, which is emitted toward the second lens group 600; due to the arrangement of the second lens group 600, the distance between the substrate 400 and the microlens array 300 is lengthened, that is, the working distance between the light spots of the second light spot array and the substrate 400 is lengthened, thereby solving the problem of wear of the microlens array 300 caused by the close distance between the substrate 400 and the microlens array 300.

[0087] Optionally, the beam expansion and light homogenization assembly 700 includes a lens and a reflector.

[0088] It is understandable that:

[0089] Those skilled in the art can match the beam expansion component and the light homogenization component 700 according to the spot size of the light emitted by the light source 100 to complete the specific configuration, which will not be described in detail here.

[0090] Another embodiment provides a lithography machine comprising the exposure system as described in any of the above embodiments.

[0091] The lithography machine adopts the aforementioned exposure system, which avoids problems such as large spot size and distortion caused by insufficient alignment between the microlens array and the DMD micromirror, thereby ensuring the lithography resolution.

[0092] The lithography machine can be a laser direct write lithography machine, which does not require a mask. Due to the arrangement of the microlens array 300 and the micromirror array 200, not only does it not need to consider the alignment problem of the traditional microlens array and DMD micromirrors, but it also solves the problem of poor lithography resolution caused by the poor alignment accuracy of traditional methods.

[0093] It is understandable that:

[0094] The lithography machine is provided with a box or frame to install and support various components of the exposure system, such as the light source 100, the beam expansion component and the uniform light component 700, the micromirror array 200, the first lens group 500, the microlens array 300 and the second lens group 600.

[0095] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0096] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0097] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0098] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0099] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0100] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. An exposure system, characterized in that: include: a light source, the light source being configured to emit light; a micromirror array, the micromirror array being configured to receive the light and convert the light into a first light spot array; A microlens array, wherein the microlens array and the light source are respectively located on opposite sides of the micromirror array, the microlens array is used to receive the first light spot array and focus the first light spot array to form a second light spot array, and the microlens array projects the second light spot array onto a substrate, the microlens array includes a light-transmitting member and a photosensitive member provided on the light-transmitting member, and the photosensitive member is made of a photosensitive material; the photosensitive member forms the microlens array under the initial irradiation of the first light spot array, so that each microlens in the microlens array corresponds one-to-one to each micromirror in the micromirror array.

2. The exposure system according to claim 1, wherein: The light-transmitting component is a light-transmitting lens, and the photosensitive component is a photosensitive coating provided on the light-transmitting lens.

3. The exposure system according to claim 2, wherein: The photosensitive coating is formed by spin-coating a photosensitive material on a light-transmitting lens.

4. The exposure system according to claim 1, wherein: The light-transmitting element is a light-transmitting lens, two of which are provided, and the photosensitive element is provided between the two light-transmitting lenses.

5. The exposure system according to claim 1, wherein: The photosensitive element is a photopolymerizable monomer; or the material of the photosensitive element is a photorefractive material.

6. The exposure system according to any one of claims 1 to 5, characterized in that: The exposure system further includes a first lens group, which is disposed between the micromirror array and the microlens array, and is used to perform a reduction process on the first light spot array.

7. The exposure system according to claim 6, wherein: The exposure system further includes a second lens group disposed between the microlens array and the substrate.

8. The exposure system according to claim 6, wherein: The micromirror array is a digital micromirror array; the exposure system further comprises a beam expansion component, which is arranged between the light source and the micromirror array.

9. The exposure system according to claim 6, wherein: The exposure system further includes a light uniformity component, which is arranged between the light source and the micromirror array.

10. A photolithography machine, characterized in that: Comprising the exposure system according to any one of claims 1 to 9.

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