A UV-LED mobile scanning photolithography device

Abstract

This utility model discloses a UV-LED moving scanning lithography apparatus, including an X-axis linear module disposed on the upper part of a frame; a wafer positioning device disposed on the lower part of the frame; a lamp source box disposed on the X-axis linear module; and multiple lamp groups arranged in an array at the lower end of the lamp source box. Each lamp group includes a lamp tube, a UV-LED disposed within the lamp tube, and two lenses. The lower ends of the lenses protrude downwards, with the upper lens protruding more than the lower lens. The number and range of lamp groups are rationally used according to the size of the lithographic product. Each lamp group has an independent lens, thus reducing processing difficulty and cost. Each lamp group has an independent current adjustment module, which, in conjunction with the irradiation intensity feedback from a linear illuminance meter, ensures uniform and sufficient reaction of the photoresist throughout, improving the accuracy and quality of the lithographic pattern.

Description

Technical Field

[0001] This utility model belongs to the field of exposure equipment technology, and in particular relates to a UV-LED moving scanning lithography device. Background Technology

[0002] Photolithography machines are key equipment in chip manufacturing, used in the photolithography process, which is the most critical step in the production process. Therefore, photolithography machines are indispensable in chip manufacturing. With the continuous improvement of photolithography technology, the use of high-power LED photolithography can obtain high-energy-density and focusable laser beams, enabling high-precision and high-resolution pattern creation to meet the needs of high-density integrated circuits and micro-nano fabrication. Current scanning photolithography methods involve keeping the light source module stationary while reciprocating the movement of a stage carrying the photolithography product to achieve the photolithography process.

[0003] Chinese patent document CN111796489A discloses a mask alignment lithography machine based on a UV-LED area array light source, comprising: a light source, using a UV-LED light source; a microlens array for collimating the emitted beam of the light source; and a mask alignment system for aligning mask marks with wafer marks. The mask alignment system includes: a mechanical system, a control system, and an image processing system. The mechanical system includes a mask stage, a wafer stage, a first driving mechanism, and a second driving mechanism. The mask and wafer are arranged in parallel. The control system controls the first and second driving mechanisms. The image processing system calibrates the overlap between the mask marks and the wafer marks. The emitted beam of the UV-LED light source forms a square exposure spot on the mask surface through the microlens array, and the mask pattern is transferred to the wafer through exposure.

[0004] In the aforementioned patented solution, the light source consists of multiple UV-LEDs sharing the same microlens array. This method is limited by the size of the product being lithographically processed; the larger the product, the larger the lens needs to be. Current lithography precision of 2μm can only achieve a maximum wafer size of 8 inches. The UV-LEDs used in lithography machines have extremely short wavelengths, which are absorbed by traditional glass materials. The lenses are made of special materials and are coated with special films made of molybdenum and silicon, making lens manufacturing difficult and costly. Furthermore, it presents a series of problems, including high precision requirements and complex daily maintenance. Utility Model Content

[0005] To overcome the technical challenges of existing technologies where multiple UV-LEDs share a single lens, requiring larger lenses for larger lithographic products, which demands high precision and complex processes, and where larger lenses increase random errors and defect rates, further complicating lens manufacturing and increasing costs, this invention aims to provide a UV-LED mobile scanning lithography device. This device utilizes a fixed wafer positioning device and a movable lamp source box. Multiple UV-LED lamp groups are arrayed on the lamp source box, each with an independent microlens. These microlenses reduce processing errors and defect rates. Simultaneously, an illuminance meter and multiple current adjustment modules are incorporated, allowing independent adjustment of the irradiance of each UV-LED lamp group, ensuring that all UV-LED lamp groups collectively create an exposure field with equal light intensity across all areas.

[0006] To achieve the above objectives, this utility model employs the following technical solution: a UV-LED moving scanning lithography apparatus, comprising a frame; an X-axis linear module horizontally disposed on the upper part of the frame; a wafer positioning device disposed on the lower part of the frame and directly below the X-axis linear module; a lamp source box disposed on the moving part of the X-axis linear module; and multiple lamp groups arrayed at the lower end of the lamp source box; wherein each lamp group includes a lamp tube disposed on the lamp source box and a UV-LED and two lenses coaxially disposed within the lamp tube from top to bottom; the lower end of each lens protrudes downward, and the protrusion height of the upper lens is greater than that of the lower lens.

[0007] The UV-LED, or ultraviolet light-emitting diode, is a type of light-emitting diode that emits ultraviolet light. The number and range of the lamp groups used are determined by the size of the photolithographic product, ensuring that the final precision is not affected by the size of the photolithographic product. Each lamp group uses two independent lenses. The smaller size of the lenses reduces processing errors and the defect rate, thereby reducing processing difficulty and cost. At the same time, the increased number of lenses enables mass production, facilitating process control and quality control. The reusability and replaceability of the lenses are also correspondingly increased.

[0008] Furthermore, it includes a Y-axis linear module disposed at the lower part of the frame, the movement direction of the Y-axis linear module being perpendicular to the movement direction of the X-axis linear module; an extension frame disposed on the moving part of the Y-axis linear module; and two alignment parts symmetrically disposed on one side of the extension frame facing the wafer positioning device, the two alignment parts being selectively movable to be directly above the wafer positioning device; wherein, the alignment part includes a slide table slidably connected to the extension frame, a multi-directional fine-tuning part disposed on the slide table, an alignment camera disposed on the multi-directional fine-tuning part, and a handwheel rotatably connected to the extension frame and drivenly connected to the slide table.

[0009] The alignment camera provides a dimensional reference for the alignment adjustment of the wafer and mask on the wafer positioning device. The multi-directional fine-tuning unit and the slide increase the compatibility of the alignment camera, allowing it to be applied to calibrate marks at different positions on the wafer / mask. The multi-directional fine-tuning unit also improves the dimensional accuracy of the alignment camera, further ensuring the alignment accuracy of the wafer and mask and improving the wafer lithography quality.

[0010] Furthermore, the lamp assembly has two array directions, one of which is perpendicular to the moving direction of the lamp source box, and the other array direction is at an angle to the moving direction of the lamp source box.

[0011] Specifically, the gap between two adjacent lamp groups in the array direction perpendicular to the moving direction of the lamp source box is completely blocked by the lamp group in the other array direction.

[0012] Specifically, the number of lamp groups in the array direction perpendicular to the moving direction of the lamp source box is greater than the number of lamp groups in the other array direction.

[0013] Specifically, the included angle is greater than or equal to 8° and less than or equal to 9°.

[0014] The light source box slides over the wafer positioning device, and each of the light groups along the movement direction synchronously performs photolithography on the wafer. The arrangement of the light groups ensures that the UV-LED light energy is evenly distributed in the movement direction, thereby improving the photolithography quality and efficiency.

[0015] Furthermore, an electrical box is provided at the upper end of the moving part of the X-direction linear module; two connecting plates are symmetrically arranged at the lower end of the electrical box, respectively located on both sides of the movement direction of the X-direction linear module; the light source box is located at the lower end of the two connecting plates; the light source box is located directly below the X-direction linear module.

[0016] Specifically, the electrical box is equipped with multiple current adjustment modules; each lamp group is electrically connected to one of the current adjustment modules; the illumination intensity of each lamp group can be adjusted independently.

[0017] Furthermore, a verification illuminance meter is disposed on the rack directly below the X-axis linear module; a linear illuminance meter is disposed on the rack directly below the X-axis linear module; the linear illuminance meter includes multiple measurement units arranged uniformly along a line; the arrangement direction of the measurement units is perpendicular to the movement direction of the lamp source box; the arrangement length of the measurement units is greater than or equal to the array length of the lamp group in the same direction; the lamp source box can be selectively moved to be directly above the wafer positioning device, the verification illuminance meter, and the linear illuminance meter.

[0018] Before photolithography, the linear illuminance meter measures the irradiation intensity on the lamp source box, and the current adjustment module adjusts the irradiation intensity of the corresponding lamp groups to ensure that the total irradiation intensity is equal and uniform throughout the lamp source box along its direction of movement, thus improving photolithography quality. The verification illuminance meter then performs a secondary verification of the linear illuminance meter's results, ensuring their accuracy and further improving the uniformity of the irradiation intensity in the lamp source box, thereby guaranteeing photolithography quality.

[0019] Specifically, the extension frame is rotatably connected to a lead screw that is driven by the slide table; the handwheel is located at one end of the lead screw; the multi-directional fine-tuning part includes a first slide plate that is horizontally slidably connected to the slide table, a second slide plate that is horizontally slidably connected to the first slide plate, and a turntable with a rotation shaft longitudinally arranged and rotatably connected to the second slide plate; the sliding direction of the first slide plate is perpendicular to the sliding direction of the second slide plate; the alignment camera is located on the turntable.

[0020] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0021] 1. This utility model rationally uses the number and range of lamp groups according to the size of the photolithography product, which has high compatibility with wafer size, and is more economical and energy-saving; and the size of the photolithography product will not affect the final accuracy.

[0022] 2. Each lamp assembly of this utility model has an independent lens. The small lens size reduces processing errors and defect rate, which reduces processing difficulty and cost. The increase in the number of lenses enables mass production, facilitates process control and quality control, and also improves the reusability and replaceability of the lenses.

[0023] 3. Each lamp group in this utility model has an independent current adjustment module. With the irradiation intensity fed back by the linear illuminance meter, the current of each lamp group, i.e. the irradiation intensity, is controlled and adjusted to make the irradiation intensity uniform along each exposure trajectory on the lamp source box along its movement path, ensuring that the photoresist reacts evenly and fully in all places, and improving the accuracy and quality of the photolithography pattern.

[0024] 4. This utility model also includes a positioning camera, which is used to adjust the position of the wafer and the mask on the wafer positioning device, thereby improving the positional accuracy of the wafer and ensuring the processing accuracy of the photolithography image. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of this utility model;

[0026] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0027] Figure 3 This is a structural schematic diagram of the X-direction linear module and the light source box of this utility model;

[0028] Figure 4 , Figure 5 This is a schematic diagram of the Y-axis linear module and the alignment part of this utility model;

[0029] Figure 6 This is a schematic diagram of the lamp assembly distribution structure of this utility model;

[0030] Figure 7 This is a schematic diagram of the structure of the lamp assembly of this utility model.

[0031] In the diagram: 1. Rack; 2. Wafer positioning device; 31. X-axis linear module; 32. Electrical box; 33. Lamp source box; 34. Lamp assembly; 341. UV-LED; 342. First lens; 343. Second lens; 344. Lamp tube; 35. Gap; 41. Linear illuminance meter; 42. Verification illuminance meter; 51. Y-axis linear module; 52. Alignment unit; 521. Slide table; 522. Handwheel; 523. Multi-directional fine-tuning unit; 524. Alignment camera; 525. Lead screw; 53. Extension frame. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0033] In the description of this utility model, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this utility model.

[0034] 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 technical features. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In this description of the utility model, "a number" means two or more, unless otherwise explicitly specified.

[0035] In this utility model, unless otherwise explicitly specified and limited, terms such as "set" and "install" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can also refer to a mechanical connection; they can refer to a direct connection or a connection through an intermediate medium; or they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0036] See Figures 1-7 A UV-LED moving scanning lithography apparatus includes a frame 1, a wafer positioning device 2 disposed at the lower part of the frame 1, an X-axis linear module 31 disposed at the upper part of the frame 1 directly above the wafer positioning device 2, an electrical box 32 disposed on the moving part of the X-axis linear module 31, and a lamp source box 33 disposed on the electrical box 32 and located below the X-axis linear module 31; the lower end of the electrical box 32 is symmetrically provided with two connecting plates located on both sides of the movement direction of the X-axis linear module 31; the lamp source box 33 is disposed at the lower end of the two connecting plates.

[0037] The lower end of the light source box 33 is arranged with multiple light groups 34. Each light group 34 has two array directions: one array direction is perpendicular to the moving direction of the light source box 33, and the other array direction forms an angle with the moving direction of the light source box 33; the angle is greater than or equal to 8° and less than or equal to 9°. The gap 35 between two adjacent light groups 34 in the array direction perpendicular to the moving direction of the light source box 33 is completely blocked by the light group 34 in the other array direction; the number of light groups 34 in the array direction perpendicular to the moving direction of the light source box 33 is greater than the number of light groups 34 in the other array direction.

[0038] The lamp assembly 34 includes a lamp tube 344 mounted on the lamp source box 33, and UV-LEDs 341 and two lenses coaxially arranged from top to bottom within the lamp tube 344; the lower ends of the lenses protrude downwards; as shown Figure 7 As shown, the two lenses are a first lens 342 located above and a second lens 343 located below; the protrusion height of the first lens 342 is greater than that of the second lens 343.

[0039] The electrical box 32 is equipped with multiple current adjustment modules; each lamp group 34 is electrically connected to one of the current adjustment modules; the illumination intensity of each lamp group 34 can be adjusted independently.

[0040] A verification illuminance meter 42 is disposed on the rack 1 directly below the X-direction linear module 31; a linear illuminance meter 41 is disposed on the rack 1 directly below the X-direction linear module 31; the linear illuminance meter 41 includes multiple measuring units arranged uniformly along a line; the arrangement direction of the measuring units is perpendicular to the movement direction of the lamp source box 33; the arrangement length of the measuring units is greater than or equal to the array length of the lamp group 34 in the same direction; the lamp source box 33 can be selectively moved to be directly above the wafer positioning device 2, the verification illuminance meter 42, and the linear illuminance meter 41.

[0041] A Y-axis linear module 51 is located in the middle of the rack 1, behind the wafer positioning device 2. The movement direction of the Y-axis linear module 51 is perpendicular to the movement direction of the X-axis linear module 31. An extension frame 53 is provided on the moving part of the Y-axis linear module 51. Two alignment parts 52 are symmetrically arranged at one end of the extension frame 53 facing the wafer positioning device 2. The alignment part 52 includes a slide table 521 slidably connected to the extension frame 53, a multi-directional fine-tuning part 523 provided on the slide table 521, an alignment camera 524 provided on the multi-directional fine-tuning part 523, a lead screw 525 rotatably connected to the extension frame 53 and drivenly connected to the slide table 521, and a handwheel 522 provided at one end of the lead screw 525. The sliding direction of the slide table 521 is perpendicular to the movement direction of the Y-axis linear module 51.

[0042] The multi-directional fine-tuning unit 523 includes a first slide plate horizontally slidably connected to the slide table 521, a second slide plate horizontally slidably connected to the first slide plate, and a turntable with a rotation shaft rotatably connected to the second slide plate and arranged longitudinally; the sliding direction of the first slide plate and the sliding direction of the second slide plate are perpendicular to each other; the alignment camera 524 is disposed on the turntable.

[0043] Working Process: Based on the required wafer size, a specified number of lamp groups 34 within a designated range are activated. The lamp source box 33 slides under the drive of the X-axis linear module 31, first passing over the linear illuminance meter 41. Each measuring unit of the linear illuminance meter 41 measures and calculates the cumulative irradiance above it, and compares the obtained cumulative irradiance values ​​(minimum cumulative irradiance to maximum cumulative irradiance). When the ratio is less than 95%, the current adjustment module calculates and adjusts the uniformity of the current values ​​of each lamp group recorded by the current adjustment module; simply put, large currents are reduced, and small currents are increased. Subsequently, the lamp source box 33 passes over the linear illuminance meter 41 again, and the above process is repeated until the ratio of minimum cumulative irradiance to maximum cumulative irradiance obtained by the measuring unit is greater than or equal to 95%. The lamp source box 33 then slides over the wafer positioning device 2, performing photolithography on the wafer on the wafer positioning device 2.

[0044] The above description is only a specific embodiment of the present utility model, but the technical features of the present utility model are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the patent scope of the present utility model.

Claims

1. A UV-LED mobile scanning photolithography device, characterized by: Includes racks; X-axis linear module, which is horizontally arranged on the upper part of the frame; A wafer positioning device is disposed at the lower part of the rack and located directly below the X-axis linear module; A light source box, wherein the light source box is disposed on the movable part of the X-direction linear module; The lamp assembly, comprising multiple lamp assemblies, is arranged in an array at the lower end of the lamp source box; The lamp assembly includes a lamp tube mounted on the lamp source box, and a UV-LED and two lenses coaxially arranged from top to bottom inside the lamp tube; the lower end of each lens protrudes downwards, and the protrusion height of the upper lens is greater than that of the lower lens.

2. The lithographic apparatus of claim 1, wherein: It includes a Y-axis linear module, which is disposed at the lower part of the frame, and the movement direction of the Y-axis linear module is perpendicular to the movement direction of the X-axis linear module. An extension frame is disposed on the movable part of the Y-direction linear module; The alignment section has two parts, which are symmetrically arranged on one side of the extension frame facing the wafer positioning device. The two alignment sections can be selectively moved to be directly above the wafer positioning device. Each alignment section includes a slide table slidably connected to the extension frame, a multi-directional fine-tuning part disposed on the slide table, an alignment camera disposed on the multi-directional fine-tuning part, and a handwheel rotatably connected to the extension frame and driven by the slide table.

3. The lithographic apparatus of any of claims 1-2, wherein: The lamp assembly has two array directions, one of which is perpendicular to the moving direction of the lamp source box, and the other array direction is at an angle to the moving direction of the lamp source box.

4. The lithographic apparatus of claim 3, wherein: The gap between two adjacent lamp groups in an array direction perpendicular to the moving direction of the lamp source box is completely blocked by the lamp group in another array direction.

5. The photolithography apparatus of claim 3, wherein: The number of lamp groups in the array direction perpendicular to the moving direction of the lamp source box is greater than the number of lamp groups in the other array direction.

6. The photolithography apparatus of claim 3, wherein: The included angle is greater than or equal to 8° and less than or equal to 9°.

7. The lithographic apparatus of any of claims 1-2, wherein: An electrical box is provided at the upper end of the moving part of the X-direction linear module; two connecting plates are symmetrically arranged at the lower end of the electrical box, respectively located on both sides of the movement direction of the X-direction linear module; the light source box is located at the lower end of the two connecting plates; the light source box is located directly below the X-direction linear module.

8. The lithographic apparatus of claim 7, wherein: The electrical box is equipped with multiple current adjustment modules; each lamp group is electrically connected to one of the current adjustment modules; the illumination intensity of each lamp group can be adjusted independently.

9. The lithographic apparatus of any of claims 1-2, wherein: A verification illuminance meter is installed on the frame directly below the X-axis linear module; a linear illuminance meter is installed on the frame directly below the X-axis linear module; the linear illuminance meter includes multiple measuring units arranged uniformly in a linear direction; the arrangement direction of the measuring units is perpendicular to the movement direction of the lamp source box; the arrangement length of the measuring units is greater than or equal to the array length of the lamp group in the same direction. The light source box can be selectively moved to be directly above the wafer positioning device, the verification illuminance meter, and the linear illuminance meter.

10. The photolithography apparatus of claim 2, wherein: The extension frame is rotatably connected to a lead screw that is driven by the slide table; the handwheel is located at one end of the lead screw; the multi-directional fine-tuning part includes a first slide plate that is horizontally slidably connected to the slide table, a second slide plate that is horizontally slidably connected to the first slide plate, and a turntable with a rotation shaft rotatably connected to the second slide plate and arranged longitudinally; the sliding direction of the first slide plate and the sliding direction of the second slide plate are perpendicular to each other; the alignment camera is located on the turntable.

Images