High-precision mask aligner for chip photolithography

Abstract

The utility model relates to chip photoetching technical field, concretely for chip photoetching is with high accuracy mask alignment device, including base and clamping mechanism, the base top is equipped with cross slide, is equipped with workstation on cross slide. The utility model discloses through screw rod drive both sides slide along the synchronous movement of the groove or opposite, can realize the big amplitude, fast " coarse adjustment " of the whole opening and closing range of clamping mechanism, the linear module of independent setting on each clamping unit, can drive two connecting blocks and L -shaped clamping plate carry out independent " fine adjustment ", make both sides clamping point can independently, the accurate adjustment position, not only can accurate adaptation mask plate's actual edge, still can after clamping exert even and controllable clamping force, ensure that mask plate is firmly positioned in the theoretical center position, no forced deviation, adapt to the quick replacement of different size mask plate, set up first protection board and T -shaped protection in the groove top, effectively block dust, particulate matter into the sliding part, reduce the failure rate.

Description

Technical Field

[0001] This utility model relates to the field of chip lithography technology, specifically a high-precision mask alignment device for chip lithography. Background Technology

[0002] As integrated circuit manufacturing technology continues to advance towards smaller nodes, the precision requirements for pattern transfer in chip photolithography have reached the nanometer level. In this process, the high-precision alignment between the mask and the silicon wafer coated with photoresist is one of the core links that determines the success or failure of pattern transfer and yield. As a key subsystem of photolithography equipment, the core function of the mask alignment device is to achieve rapid and precise alignment between the mask and the wafer.

[0003] Currently, mask alignment devices typically include a stage for carrying and precisely positioning wafers and a clamping mechanism for holding and positioning the mask. Traditional solutions often use simple mechanical grippers. The position adjustment flexibility of traditional clamping mechanisms is limited, making it difficult to adapt to mask plates of different sizes and specifications, which affects the versatility of the equipment and changeover efficiency. Therefore, high-precision mask alignment devices for chip lithography are needed to improve the above problems. Utility Model Content

[0004] To address the limitations of traditional clamping mechanisms in terms of position adjustment flexibility and adaptability to photomasks of different sizes and specifications, this invention provides a high-precision photomask alignment device for chip lithography to solve the aforementioned problems.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A high-precision mask alignment device for chip lithography includes a base and a clamping mechanism. The base has a cross slide on top, and a worktable on the cross slide. The clamping mechanism includes a threaded rod and a guide rod. Slots are provided on both sides of the top of the worktable, and the threaded rod and guide rod are respectively positioned in the two slots. Slider blocks are located at both ends of the threaded rod and guide rod. A linear module is located on top of the two sliders on the same side as the threaded rod and guide rod. Two connecting blocks are provided on the linear module. An L-shaped clamping plate is located on one side of each connecting block. Rectangular slots are formed on the inner sides of both ends of the L-shaped clamping plate. The groove is equipped with cylindrical rods, and auxiliary rollers are fitted on the two cylindrical rods. The bottom of the L-shaped clamping plate is equipped with a support plate. One straight module has a first protective plate at both ends on one side, and another straight module has a T-shaped protective plate at both ends on one side. The bottom of the first protective plate has a T-shaped groove, and one end of the T-shaped protective plate fits into the T-shaped groove. The first protective plate and the T-shaped protective plate on the same side cover the top of the slide groove. The slider at both ends of the threaded rod is equipped with an oil injection pipe. One end of the two oil injection pipes passes through the top of the first protective plate and the T-shaped protective plate and extends to the outside.

[0007] As a preferred embodiment of this utility model, an installation groove is provided on the worktable, a placement plate is provided inside the installation groove, and a wafer placement groove is provided on the top of the placement plate.

[0008] As a preferred embodiment of this utility model, a rectangular through slot is provided on the top of the workbench, which is connected to the mounting slot, and the wafer placement slot corresponds to the rectangular through slot.

[0009] As a preferred embodiment of this utility model, the linear module is a double-slider linear module structure.

[0010] As a preferred embodiment of this utility model, the threaded rod is a bidirectional threaded rod structure.

[0011] As a preferred embodiment of this utility model, a drive source is provided on one side of the workbench, and the output end of the drive source is connected to one end of the threaded rod.

[0012] As a preferred embodiment of this utility model, a light source platform is provided on one side of the top of the base, and a cross slide is located below the light source platform.

[0013] As a preferred embodiment of this utility model, a baffle is provided on the outer side of the base.

[0014] Compared with existing technologies,

[0015] 1. This utility model uses a threaded rod to drive the sliders on both sides to move synchronously towards or away from each other along the slide groove, which can adjust the overall opening and closing range of the clamping mechanism. The linear module independently set on each clamping unit can drive the two connecting blocks and L-shaped clamping plates to make independent adjustments, so that the clamping points on both sides can be adjusted independently and precisely. It can not only accurately fit the actual edge of the mask, but also apply a uniform and controllable clamping force after clamping, ensuring that the mask is firmly positioned in the theoretical center position without forced offset, so as to adapt to the rapid replacement of mask plates of different sizes. At the same time, a first protective plate and a T-shaped protective plate are set at the top of the slide groove to effectively prevent dust and particles from entering the sliding parts and reduce the failure rate.

[0016] 2. This utility model uses an L-shaped clamping plate with auxiliary rollers at both ends for clamping. The auxiliary rollers can form rolling contact with the side of the mask plate during clamping, which transforms the traditional sliding friction into rolling friction. This greatly reduces the risk of scratches or wear on the edge of the mask plate during clamping. At the same time, compared with point contact or rigid surface contact, the line contact method can distribute the clamping force more evenly, effectively avoiding large-area bending deformation of the mask plate caused by local stress concentration. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2This is a schematic diagram of the worktable and cross slide structure of this utility model;

[0019] Figure 3 This is a schematic diagram of the placement plate structure of this utility model;

[0020] Figure 4 This is a schematic diagram of the clamping mechanism of this utility model;

[0021] Figure 5 This is a schematic diagram of the oil injection pipe structure of this utility model;

[0022] Figure 6 This is a schematic diagram of the L-shaped clamping plate structure of this utility model.

[0023] In the diagram: 1. Base; 2. Light source platform; 3. Cross slide; 4. Worktable; 41. Mounting slot; 42. Slide; 5. Placement plate; 51. Wafer placement slot; 6. Clamping mechanism; 61. Threaded rod; 62. Drive source; 63. Guide rod; 64. Slider; 65. Linear module; 66. Connecting block; 67. L-shaped clamping plate; 68. Rectangular slot; 69. Cylindrical rod; 610. Auxiliary roller; 611. Support plate; 612. First protective plate; 613. T-shaped protective plate; 614. T-slot; 615. Oil injection pipe. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0025] Example: Please refer to Figure 1-6The high-precision mask alignment device for chip lithography shown includes a base 1 and a clamping mechanism 6. The base 1 serves as the foundation and mounting platform for the entire device, providing a stable and level foundation for all upper-level components. Its rigidity and stability directly determine the system's ability to resist external vibrations and maintain precision. A cross slide 3 is bolted to the top of the base 1. The cross slide 3 is composed of two sets of orthogonally superimposed precision linear guides, enabling independent, high-precision linear movement of the carrier in the X and Y axes. By controlling the movement of the cross slide 3, specific alignment marks on the wafer can be aligned with the mask. The position where the film plate mark overlaps is moved to below the exposure light source. The worktable 4 is bolted to the cross slide 3. The worktable 4 is the moving part of the cross slide 3, which directly supports the wafer and the clamping mechanism 6. The clamping mechanism 6 includes a threaded rod 61 and a guide rod 63. Slide grooves 42 are respectively opened on both sides of the top of the worktable 4. The slide grooves 42 provide precise track constraints for the lateral movement of the entire clamping mechanism 6. The threaded rod 61 is fixed in the slide groove 42 by bearings, and the guide rod 63 is welded in the slide groove 42. The threaded rod 61 and the guide rod 63 form a classic "lead screw and guide rod" transmission pair. The threaded rod 61 rotates under the drive of the drive source 62, converting rotational motion into linear motion. The guide rod 63 ensures that the motion direction is not deviated and bears bending moment. The two ends of the threaded rod 61 are threaded with sliders 64, and the two ends of the guide rod 63 are slidably fitted with sliders 64. The sliders 64 are transition pieces connecting the threaded rod 61 and the guide rod 63 to the upper linear module 65, transmitting rotational and linear motion to the clamping and actuating components. The linear module 65 is bolted to the top of the two sliders 64 located on the same side of the threaded rod 61 and the guide rod 63. The linear module 65 is mounted on the top of the sliders 64 and is another high-precision linear drive unit. Two connecting blocks 66 are bolted to the linear module 65. An L-shaped clamping plate 67 is welded to one side of the connecting block 66. The connecting block 66 is an extension of the slider of the linear module 65 and is used to install the L-shaped clamping plate.L-shaped clamping plates 67 can contact and clamp the mask from two adjacent edges, providing more stable constraints. Rectangular grooves 68 are respectively formed on the inner sides of both ends of the L-shaped clamping plates 67. Cylindrical rods 69 are welded inside the two rectangular grooves 68, and auxiliary rollers 610 are rotatably fitted on the two cylindrical rods 69. The auxiliary rollers 610 can form rolling contact with the side of the mask during clamping, transforming traditional sliding friction into rolling friction. A support plate 611 is welded to the bottom of the L-shaped clamping plates 67, supporting the mask. One linear module 65 has first protective plates 612 at both ends on one side, and another linear module 65 has T-shaped protective plates 613 at both ends on one side. The bottom of the first protective plate 612 has a T-shaped groove 614, and the bottom of the T-shaped protective plate 614... One end of the 3 is fitted into the T-groove 614. The first protective plate 612 and the T-shaped protective plate 613 on the same side cover the top of the slide groove 42. The first protective plate 612, the T-shaped protective plate 613 and the T-groove 614 form a dynamic, movable sealed protective structure that can move with the slider, effectively preventing dust, particles, liquid splashes and other contaminants from falling into the precision slide groove and screw mechanism. An oil injection pipe 615 is provided on one side of the slider 64 at both ends of the threaded rod 61. One end of the two oil injection pipes 615 extends to the outside through the top of the first protective plate 612 and the T-shaped protective plate 613 respectively. The oil injection pipes 615 provide a centralized lubrication channel without disassembling the protective plate. Maintenance personnel can add lubricating oil or grease to the threaded rod through the exposed oil injection pipe port without disassembling the protective plate.

[0026] In this embodiment, specific references Figure 1 , Figure 2 , Figure 3 , Figure 4 The worktable 4 has a mounting slot 41, and a placement plate 5 is placed inside the mounting slot 41. The mounting slot 41 and the placement plate 5 constitute a modular wafer carrier unit. The placement plate 5 can be easily put in or taken out, which is convenient for maintenance or replacement of carriers that are adapted to different specifications of wafers. The top of the placement plate 5 has a wafer placement groove 51, which is a shallow groove that matches the shape of the wafer. It is used to perform preliminary, coarse positioning and limiting of the wafer to prevent it from sliding in the horizontal direction.

[0027] In this embodiment, specific references Figure 1 , Figure 2 , Figure 3 , Figure 4 The top of the worktable 4 is provided with a rectangular through slot 43, which is connected to the mounting slot 41. The wafer placement slot 51 corresponds to the rectangular through slot 43. The rectangular through slot 43 serves as the optical path channel for the back-side light alignment system.

[0028] In this embodiment, specific references Figure 4The linear module 65 is a dual-slider linear module structure, which has two sliders that can be controlled independently or in conjunction, so that the two connecting blocks 66 and the L-shaped clamping plate 67 on them can move independently, achieve synchronous clamping, and can also make asymmetrical fine adjustments to the two clamping points according to the shape or position error of the mask plate.

[0029] In this embodiment, specific references Figure 4 The threaded rod 61 is a bidirectional threaded rod structure with opposite thread directions at both ends of the rod. When the threaded rod 61 rotates, the sliders 64 at both ends will move synchronously towards or away from the center, ensuring that the clamping components on both sides of the clamping mechanism 6 can synchronously approach or move away from the center, achieving fast and automatic centering clamping, and improving operating efficiency and clamping symmetry.

[0030] In this embodiment, specific references Figure 4 A drive source 62 is bolted to one side of the worktable 4. The output end of the drive source 62 is fixedly connected to one end of the threaded rod 61. The drive source 62 is a servo motor that provides power to the threaded rod 61, thereby realizing the motor-driven automation of the clamping action.

[0031] In this embodiment, specific references Figure 1 A light source stage 2 is welded to one side of the top of the base 1. The light source stage 2 fixes and positions the exposure light source and is located directly above the worktable 4. The cross slide 3 is located below the light source stage 2.

[0032] In this embodiment, specific references Figure 1 A baffle is welded to the outside of the base 1 to provide safety protection and prevent operators from accidentally contacting the moving parts.

[0033] In operation, the wafer to be exposed is placed in the wafer placement slot 51 on the placement plate 5. Then, the placement plate 5 is placed in the mounting slot 41 of the worktable 4. The mask plate with the target circuit is placed above the worktable 4, approximately in the center of the clamping mechanism 6. The drive source 62 is activated, which drives the bidirectional threaded rod 61 to rotate, causing the slider 64 and the double slider linear module 65 to move. This causes the L-shaped clamping plate 67 mounted on the module slider to move longitudinally from both sides of the mask plate to approach the edge of the mask plate. At the same time, the connecting block 66 controlled by the linear module 65 drives the L-shaped clamping plate 67 to move laterally, clamping the other two sides of the mask plate and keeping the mask plate in the center position.

[0034] When the L-shaped clamping plate contacts the edge of the mask plate, the pressure is first applied to the auxiliary roller 610, which transforms the traditional sliding friction into rolling friction.

[0035] During exposure, the cross slide 3 issues a command to drive the stage 4 to move, which moves the position where the specific alignment mark on the wafer coincides with the mark on the mask to below the exposure light source. Ultraviolet light for exposure is emitted through the light source stage 2 to perform pattern exposure.

[0036] The cross slide 3, drive source 62, and linear module 65 used in this utility model are all existing known electrical devices, and all can be purchased and used directly on the market. Their structure, circuit, and control principle are all existing known technologies. Therefore, the structure, circuit, and control principle of the cross slide 3, drive source 62, and linear module 65 will not be described in detail here.

[0037] All standard parts used in this application can be purchased from the market. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art and are also general components, which are common knowledge in this field.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision mask alignment device for chip photolithography, comprising a base (1), characterized in that: The base (1) is provided with a cross slide (3) on top, and a worktable (4) is provided on the cross slide (3); It also includes a clamping mechanism (6), which includes a threaded rod (61) and a guide rod (63). The top two sides of the worktable (4) are respectively provided with slide grooves (42), and the threaded rod (61) and the guide rod (63) are respectively arranged in the two slide grooves (42). The threaded rod (61) and the guide rod (63) are respectively provided with sliders (64) at both ends. The top of the two sliders (64) located on the same side of the threaded rod (61) and the guide rod (63) is provided with a linear module (65). The linear module (65) is provided with two connecting blocks (66). The connecting block (66) has an L-shaped clamp (67) on one side. The inner sides of the two ends of the L-shaped clamp (67) are respectively provided with rectangular grooves (68). The two rectangular grooves (68) are provided with cylindrical rods (69). The two cylindrical rods (69) are fitted with auxiliary rollers (610). The bottom of the L-shaped clamp (67) is provided with a support plate (611). One of the linear modules (65) has a first protective plate (612) at both ends on one side, and another linear module (65) has a T-shaped protective plate (613) at both ends on one side. The bottom of the first protective plate (612) has a T-shaped groove (614), and one end of the T-shaped protective plate (613) fits into the T-shaped groove (614). The first protective plate (612) and the T-shaped protective plate (613) on the same side cover the top of the slide groove (42). An oil injection pipe (615) is provided on one side of the slider (64) at both ends of the threaded rod (61). One end of the two oil injection pipes (615) extends to the outside through the top of the first protective plate (612) and the T-shaped protective plate (613), respectively.

2. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: The workbench (4) is provided with an installation slot (41), and a placement plate (5) is provided inside the installation slot (41). A wafer placement slot (51) is provided on the top of the placement plate (5).

3. The high-precision mask alignment device for chip lithography according to claim 2, characterized in that: The top of the workbench (4) is provided with a rectangular through slot (43), which is connected to the mounting slot (41), and the wafer placement slot (51) corresponds to the rectangular through slot (43).

4. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: The linear module (65) is a dual-slider linear module structure.

5. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: The threaded rod (61) is a bidirectional threaded rod structure.

6. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: A drive source (62) is provided on one side of the workbench (4), and the output end of the drive source (62) is connected to one end of the threaded rod (61).

7. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: The base (1) has a light source platform (2) on one side of its top, and the cross slide (3) is located below the light source platform (2).

8. The high-precision mask alignment device for chip lithography according to claim 1, characterized in that: The base (1) is provided with a baffle on its outer side.

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