A reticle inspection chuck

Abstract

The utility model relates to a mask detection chuck relates to mask detection device technical field, including the base plate and at least two clamping components for extruding mask, the one side of base plate is provided with the article groove, the article groove has four tank walls, and among them mutually perpendicular two tank walls are first clamping surface and second clamping surface respectively, the base plate still is provided with a plurality of adsorption hole that all links to each other article groove groove bottom, each adsorption hole all are used for the intercommunication negative pressure generator, each clamping component all are fixed in base plate, and distribute in with first clamping surface and second clamping surface opposite position. The utility model can realize the stable clamping to mask in the detection process, and will not cause the damage to mask simultaneously.

Description

Technical Field

[0001] This utility model relates to the technical field of mask detection devices, and in particular to a mask detection chuck. Background Technology

[0002] In semiconductor photolithography, the photomask is a core component, and its surface quality directly determines the chip manufacturing yield. If there are micro-defects such as scratches or particles on the photomask surface, these can transfer to the wafer surface during photolithography, leading to chip malfunction or performance degradation and causing significant product loss. Therefore, before being used, photomasks must be screened for defects using specialized photomask inspection equipment to ensure that their surface quality meets process requirements.

[0003] In the mask inspection process, ensuring the stable and precise fixation of the mask is a prerequisite for guaranteeing inspection accuracy. This task is undertaken by the clamping device (commonly known in the industry as a chuck). The clamping effect of the chuck directly affects the positioning accuracy of the mask. If the mask experiences positional shifts, level deviations, or surface deformation during clamping, it will lead to a decrease in the accuracy of the inspection equipment in identifying defects. Specifically, this manifests as misjudgment of defect locations and missed detection of minor defects, thereby affecting the reliability of the mask quality evaluation.

[0004] As semiconductor chips evolve towards higher integration and smaller manufacturing processes, the requirements for the dimensional accuracy and surface quality of photomasks continue to increase. Consequently, the accuracy requirements for photomask inspection equipment are also rising, further demanding higher standards for the performance of clamping chucks. Currently, clamping chucks must simultaneously meet multiple requirements, including high stability, high flatness, accurate positioning, and preventing excessive compression and contamination of the photomask during clamping.

[0005] However, existing mask clamping methods mostly employ single mechanical clamping, vacuum adsorption, or electrostatic chuck types, each with its own technical shortcomings, making it difficult to meet the needs of clamping and testing. Mechanical clamping type: The mask is directly clamped by the jaws. During the clamping process, uneven force applied by the jaws can cause the mask to lift up, which can damage the level of the mask to be tested and thus affect the optical imaging accuracy of the detection system. At the same time, the large clamping force required to ensure clamping stability may cause indentation or plastic deformation on the surface of the mask, damaging the functional areas of the mask.

[0006] Vacuum adsorption type: This method relies on negative pressure adsorption to fix the mask on the chuck surface, but it cannot actively position and correct the mask. The final position of the mask depends entirely on the placement accuracy of the external robotic arm. Since slight deviations are unavoidable during the placement process by the robotic arm, it is difficult to guarantee the positional accuracy of the mask during inspection, which can easily lead to defect location errors.

[0007] Electrostatic chuck type: It uses electrostatic adsorption force to fix the mask, but it also lacks an effective position correction function and cannot correct the initial placement deviation of the mask.

[0008] In summary, existing single clamping methods all have insurmountable technical bottlenecks and cannot meet the comprehensive performance requirements of the clamping device for mask detection. Therefore, it is urgent to develop a new mask clamping device to solve the problems of insufficient detection and positioning accuracy and easy damage to the mask in the existing technology. Utility Model Content

[0009] This invention provides a mask detection chuck that can stably clamp the mask during the detection process without damaging it.

[0010] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A mask inspection chuck includes a substrate and at least two clamping assemblies for pressing a mask. A storage groove is formed on one side of the substrate, and the storage groove has four groove walls, wherein two mutually perpendicular groove walls are respectively a first clamping surface and a second clamping surface. The substrate also has a plurality of adsorption holes that are all connected to the bottom of the storage groove. Each adsorption hole is used to connect to a negative pressure generator. Each clamping assembly is fixed to the substrate and distributed at a position opposite to the first clamping surface and the second clamping surface.

[0011] The beneficial effects of this utility model are as follows: During the testing process, the mask is placed in the storage slot, and the mask blocks the adsorption holes. Each clamping component simultaneously presses the mask against the first clamping surface and the second clamping surface. At the same time, the negative pressure generator is activated to generate negative pressure adsorption on the mask through the adsorption holes. Thus, the mask is positioned and fixed during the testing process by combining mechanical clamping and negative pressure adsorption, which can ensure the stability of the mask position and achieve stable clamping of the mask during the testing process without damaging the mask.

[0012] Based on the above technical solution, the present invention can be further improved as follows.

[0013] Furthermore, each of the clamping components includes a linear drive fixedly mounted on the substrate and a clamping push rod with one end connected to the linear drive, the other end of the clamping push rod being used to press the mask.

[0014] Furthermore, each of the clamping components also includes a jaw fixedly connected to the other end of the clamping push rod, and the clamping surface of each jaw is an arc surface structure.

[0015] Furthermore, each of the clamping components also includes an adapter rod, one end of which is detachably connected to the driving end of the corresponding linear drive, and the other end of which is detachably connected to one end of the corresponding clamping push rod. The linear drive and the clamping push rod of the same clamping component are arranged side by side, and each of the clamping push rods is slidably connected to the substrate.

[0016] Furthermore, the bottom of the storage tank is provided with multiple adsorption slots, and each adsorption hole is connected to the bottom of each adsorption slot.

[0017] Furthermore, the substrate is provided with a plurality of dust extraction holes for connecting to a dust collector, each of the dust extraction holes for connecting to the wall of the storage compartment, and the storage compartment is provided with a plurality of dust extraction slots for connecting to one side of the substrate.

[0018] Furthermore, the substrate is equipped with two detection photoelectric sensors, which are disposed opposite to each other on two opposite walls of the storage slot.

[0019] Furthermore, a detection port is formed through the center of the bottom of the storage compartment.

[0020] Furthermore, a plurality of clearance grooves are provided on one side of the substrate, and each of the clearance grooves is connected to the storage groove.

[0021] Furthermore, the substrate is coated with an antistatic plating layer. Attached Figure Description

[0022] Figure 1 This is the first axonometric view of the mask plate detection chuck of this utility model, which is generally shown from the frontal view. Figure 2 For the present utility model Figure 1 Enlarged view of section A; Figure 3 For the present utility model Figure 1 A structural diagram from another perspective; Figure 4 For the present utility model Figure 3 Enlarged view of section B; Figure 5 For the present utility model Figure 3 A structural diagram from another perspective; Figure 6 For the present utility model Figure 5 Enlarged view of section C; Figure 7 This is a second axonometric view of the mask plate detection chuck of this utility model, generally shown from the rear view direction; Figure 8 For the present utility model Figure 7 Enlarged view of section D in the middle; Figure 9 For the present utility model Figure 7 Enlarged view of section E in the middle.

[0023] The attached diagram lists the components represented by each number as follows: 1. Substrate; 11. Storage slot; 111. First clamping surface; 112. Second clamping surface; 113. Detection port; 114. Clearance slot; 12. Adsorption hole; 121. Adsorption slot; 13. Mounting slot; 14. Dust extraction hole; 141. Dust extraction slot; 2. Clamping assembly; 21. Linear drive component; 22. Clamping push rod; 23. Gripper; 24. Adapter rod; 3. Detect photoelectric sensors. Detailed Implementation

[0024] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0025] Example 1 like Figures 1-9 A mask detection chuck includes a substrate 1 and at least two clamping components 2 for pressing a mask. A storage groove 11 is provided on one side of the substrate 1. The storage groove 11 has four groove walls, and two mutually perpendicular groove walls are respectively a first clamping surface 111 and a second clamping surface 112. The substrate 1 also has a plurality of adsorption holes 12 that are all connected to the bottom of the storage groove 11. Each adsorption hole 12 is used to connect to a negative pressure generator. Each clamping component 2 is fixed to the substrate 1 and distributed at a position opposite to the first clamping surface 111 and the second clamping surface 112.

[0026] The beneficial effects of this embodiment are as follows: During the detection process, the mask is placed in the storage slot 11, and the mask blocks the adsorption hole 12. Each clamping component 2 simultaneously presses the mask against the first clamping surface 111 and the second clamping surface 112. At the same time, the negative pressure generator is activated to generate negative pressure adsorption on the mask through the adsorption hole 12. Thus, the mask is positioned and fixed during the detection process by combining mechanical clamping and negative pressure adsorption, which can ensure the stability of the mask position and achieve stable clamping of the mask during the detection process without damaging the mask.

[0027] Specifically, addressing the inherent shortcomings of existing single-clamping methods such as mechanical clamping, vacuum adsorption, and electrostatic chuck, this device employs a technical solution combining mechanical clamping and negative pressure adsorption. For mechanical clamping methods, uneven force at a single point can easily lead to mask warping, poor leveling, and surface damage due to excessive clamping force. This chuck places the mask within the storage slot 11, and multiple clamping components 2 simultaneously press it against the first clamping surface 111 and the second clamping surface 112. Combined with the limiting function of the storage slot, force balance is achieved. The auxiliary fixation provided by negative pressure adsorption reduces the mechanical clamping force, effectively preventing leveling deviations and surface damage. Surface deformation; for the shortcomings of vacuum adsorption type which cannot be positioned and aligned and relies on the placement accuracy of robotic arms, the reference surface of the placement slot and the active clamping action of the clamping components can achieve precise alignment of the mask plate. In addition, the negative pressure adsorption of the adsorption hole 12 forms a double fixation of "mechanical positioning + negative pressure bonding", which not only eliminates the influence of placement deviation, but also improves the stability against interference from equipment vibration, airflow disturbance and other disturbances. For the problems of electrostatic chuck type which has electrostatic interference detection signal and high cost, this device does not require electrostatic adsorption, eliminates electrostatic interference from the source, and has lower manufacturing and maintenance costs for mechanical and negative pressure structures, and higher structural reliability.

[0028] The number of clamping components 2 can be two, three, four, or five, etc., and correspondingly, the number of clamping components 2 opposite to the first clamping surface 111 or the second clamping surface 112 can be one, two, three, or four, etc. In the figure, two clamping components 2 are shown opposite to the first clamping surface 111 and the second clamping surface 112, respectively.

[0029] Generating negative pressure using a negative pressure generator is common practice and is considered a conventional method or common knowledge, so it will not be elaborated upon here. Those skilled in the art can select any negative pressure generator according to their needs or convenience. A negative pressure generator can specifically be a vacuum pump or a vacuum ejector, etc.

[0030] Example 2 like Figures 7-9 Based on Embodiment 1, each clamping assembly 2 includes a linear drive 21 fixedly mounted on the substrate 1 and a clamping push rod 22 with one end connected to the linear drive 21. The other end of the clamping push rod 22 is used to press the mask.

[0031] The beneficial effect of adopting the preferred solution in the above embodiments is that after the mask is placed in place, the linear drive 21 is activated to drive the clamping push rod 22 to move, so that the other end of the clamping push rod 22 squeezes the mask. Under the combined action of the corresponding first clamping surface 111 or second clamping surface 112, the mask can be stably clamped.

[0032] It is common practice to drive the clamping push rod 22 to move linearly by using the linear drive component 21. These are all conventional methods or common knowledge, and will not be elaborated here. Those skilled in the art can select any linear drive component 21 according to their needs or convenience.

[0033] The linear drive component 21 can specifically be a spring cylinder, ball screw transmission mechanism, synchronous belt drive, electric push rod, electric cylinder, cam mechanism, linear motor, or other linear drive mechanisms. The figure only shows a spring cylinder; controlling the air supply and de-supply of the spring cylinder controls the loosening and clamping.

[0034] Example 3 like Figures 7-9 Based on embodiments 1 and 2, each clamping component 2 also includes a jaw 23 fixedly connected to the other end of the clamping push rod 22, and the clamping surface of each jaw 23 is an arc surface structure.

[0035] The advantage of adopting the preferred solution in the above embodiments is that, during the clamping process, the arc-shaped structure of the gripper 23 can reduce the possibility of damage to the sidewall of the mask.

[0036] The gripper 23 can be made of materials such as rubber or silicone.

[0037] The linear drive component 21 employs a spring cylinder, which controls the opening and closing of the gripper 23 by controlling the air supply and de-air supply of the spring cylinder. During air supply, the gripper 23 retracts under the action of air pressure, releasing its grip. During de-air supply, the gripper 23 extends under the force of the internal spring to clamp. The clamping force of the spring gripper 23 during de-air supply can be adjusted within a certain range according to the different lengths of the gripper push rod. A linear guide mechanism is also provided to ensure that the clamping force is perpendicular to the side of the mask during clamping, ensuring uniform clamping force.

[0038] Example 4 like Figures 7-9 Based on embodiments 1-3, each clamping component 2 further includes an adapter rod 24. One end of each adapter rod 24 can be detachably connected to the driving end of the corresponding linear drive 21, and the other end can be detachably connected to one end of the corresponding clamping push rod 22. The linear drive 21 and clamping push rod 22 of the same clamping component 2 are arranged side by side, and each clamping push rod 22 is slidably connected to the substrate 1.

[0039] The beneficial effect of the preferred solution in the above embodiments is that, through the adapter rod 24, when the linear drive member 21 extends and retracts, the clamping push rod 22 extends and retracts, thereby achieving the clamping or releasing of the mask. Moreover, the linear drive member 21 and the clamping push rod 22 of the same clamping assembly 2 are arranged side by side. Compared with the method of arranging the linear drive member 21 and the clamping push rod 22 on the same straight line, the space occupied can be reduced, and the size of the substrate 1 can be reduced.

[0040] The clamping push rod 22 is slidably mounted on the base plate 1, which can relatively ensure the stability of the clamping push rod 22.

[0041] Furthermore, based on the above embodiments, the linear drive component 21 employs a spring cylinder, controlling the air supply and de-airing of the spring cylinder to control the opening and closing of the gripper 23. During the air supply process, the gripper 23 retracts under the action of air pressure, releasing its grip. During the de-airing process, the gripper 23 extends under the force of the internal spring to clamp. During the de-airing process, the clamping force of the gripper 23 can be adjusted within a certain range according to the different lengths of the clamping push rod 22; that is, the clamping push rod 22 can be removed and replaced with clamping push rods 22 of different lengths.

[0042] Meanwhile, the clamping push rod 22 can be slidably installed through a linear bearing to ensure that the clamping force is perpendicular to the side of the mask during the clamping process, thus ensuring uniform clamping force.

[0043] In this invention, a plurality of mounting slots 13, each connected to a storage slot 11, are provided on the substrate 1. The number of mounting slots 13 is equal to the number of clamping components 2, and each clamping component 2 is installed in each mounting slot 13.

[0044] Example 5 like Figures 1-6 Based on embodiments 1-4, the bottom of the storage tank 11 is provided with multiple adsorption tanks 121, and each adsorption hole 12 is connected to the bottom of each adsorption tank 121.

[0045] The beneficial effect of adopting the preferred solution in the above embodiments is that the adsorption groove 121 increases the contact area of ​​the negative pressure acting on the mask. Compared with the direct adsorption of a single adsorption hole 12, it can make the negative pressure adsorption force more evenly distributed at the bottom of the mask, avoid the local adsorption force concentration causing small deformation on the surface of the mask, and at the same time ensure the consistent fit between the mask and the bottom of the placement groove 11, thus improving the overall level stability.

[0046] In addition, the corresponding interconnected structure of multiple adsorption tanks 121 and adsorption holes 12 can form a multi-point, balanced adsorption system. Even if a certain adsorption hole or pipeline is slightly blocked, the remaining adsorption tanks 121 can still maintain a stable negative pressure adsorption effect, which enhances the fault tolerance and reliability of the adsorption system, ensures the continuity of the fixed state of the mask during the detection process, and avoids positional shift problems caused by local adsorption failure.

[0047] Example 6 like Figures 1-6 Based on embodiments 1-5, the substrate 1 is further provided with a plurality of dust extraction holes 14 for connecting to a dust collector. Each dust extraction hole 14 is used to connect to the wall of the storage compartment 11, and the storage compartment 11 is provided with a plurality of dust extraction compartments 141 that are connected to one side of the substrate 1.

[0048] The advantage of the preferred solution in the above embodiments is that, during the clamping and detection process, dust particles that may be generated in the surrounding area can be removed by a dust collector, ensuring the cleanliness of the surrounding environment.

[0049] During the extraction process, dust enters the dust extraction hole 14 from the dust extraction tank 141 and is then discharged into the waste gas pipeline specified by the plant.

[0050] Example 7 like Figure 7 and Figure 8 Based on embodiments 1-6, the substrate 1 is equipped with two detection photoelectric sensors 3, which are arranged opposite to each other on the two opposite walls of the storage slot 11.

[0051] The advantage of adopting the preferred solution in the above embodiments is that, during detection, the photoelectric sensor 3 can be used to detect whether the mask is accurately placed in the storage slot 11.

[0052] Among them, the photoelectric detection 3 can be a photoelectric sensor.

[0053] It should be noted that the working principle and wiring method of photoelectric sensors are commonplace and are all conventional methods or common knowledge, so they will not be elaborated here. Those skilled in the art can make any selections according to their needs or convenience.

[0054] Example 8 like Figure 1 and Figure 2 Based on Examples 1-7, a detection port 113 is formed through the middle of the bottom of the storage tank 11.

[0055] The beneficial effect of adopting the preferred solution in the above embodiments is that, during the detection process, the substrate 1 is fixedly installed, the mask is placed in the storage groove 11, and the detection probe can simultaneously detect both sides of the mask in the thickness direction through the opening direction of the storage groove 11 and the detection port 113, thereby improving the detection efficiency.

[0056] Based on the above embodiment, each adsorption hole 12 is distributed on each wall of the placement groove 11 to adsorb the circumferential edge of the placed mask, so as to ensure the adsorption stability of the mask.

[0057] Example 9 like Figure 1 and Figure 5 Based on embodiments 1-8, a plurality of clearance grooves 114 are provided on one side of the substrate 1, and each clearance groove 114 is connected to the storage groove 11.

[0058] The beneficial effect of adopting the preferred solution in the above embodiments is that by opening the avoidance groove 114, it is convenient to place the mask plate in the storage groove 11, so as to avoid mechanical grippers and other equipment.

[0059] The number of clearance slots 114 can be two, three, four or five, etc. The figure shows two, which are relatively distributed on the two opposite walls of the storage slot 11.

[0060] Example 10 Based on Examples 1-9, substrate 1 is coated with an antistatic plating layer.

[0061] The advantage of adopting the preferred solution in the above embodiments is that the antistatic coating ensures that the mask is free from electrostatic interference during the testing process.

[0062] In the prior art, the static electricity generated during the electrostatic adsorption process may interfere with the electronic signal acquisition of the detection equipment, affecting the sensitivity of defect detection. Moreover, its manufacturing and maintenance costs are relatively high, which is not conducive to large-scale promotion and application. Therefore, the present invention coats the substrate 1 with an antistatic coating to prevent electrostatic interference.

[0063] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0064] 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0065] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0066] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0068] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A mask plate detection chuck, characterized in that, The device includes a substrate (1) and at least two clamping assemblies (2) for extruding a mask. A storage groove (11) is provided on one side of the substrate (1). The storage groove (11) has four groove walls, and two mutually perpendicular groove walls are respectively a first clamping surface (111) and a second clamping surface (112). The substrate (1) also has a plurality of adsorption holes (12) that are all connected to the bottom of the storage groove (11). Each adsorption hole (12) is used to connect to a negative pressure generator. Each clamping assembly (2) is fixed to the substrate (1) and distributed at a position opposite to the first clamping surface (111) and the second clamping surface (112).

2. The mask plate detection chuck according to claim 1, characterized in that, Each of the clamping components (2) includes a linear drive (21) fixedly mounted on the substrate (1) and a clamping push rod (22) with one end connected to the linear drive (21). The other end of the clamping push rod (22) is used to press the mask.

3. The mask plate detection chuck according to claim 2, characterized in that, Each of the clamping components (2) further includes a jaw (23) fixedly connected to the other end of the clamping push rod (22), and the clamping surface of each jaw (23) is an arc surface structure.

4. The mask plate detection chuck according to claim 2, characterized in that, Each of the clamping components (2) further includes an adapter rod (24). One end of each adapter rod (24) can be detachably connected to the driving end of the corresponding linear drive (21), and the other end can be detachably connected to one end of the corresponding clamping push rod (22). The linear drive (21) and the clamping push rod (22) of the same clamping component (2) are arranged side by side, and each clamping push rod (22) is slidably connected to the substrate (1).

5. The mask plate detection chuck according to claim 1, characterized in that, The bottom of the storage tank (11) is provided with multiple adsorption tanks (121), and each adsorption hole (12) is connected to the bottom of each adsorption tank (121).

6. The mask plate detection chuck according to claim 1, characterized in that, The substrate (1) is also provided with a plurality of dust extraction holes (14) for connecting to a dust collector. Each of the dust extraction holes (14) is used to connect to the wall of the storage slot (11), and the storage slot (11) is provided with a plurality of dust extraction slots (141) for connecting to one side of the substrate (1).

7. A mask plate detection chuck according to any one of claims 1-6, characterized in that, The substrate (1) is equipped with two detection photoelectric sensors (3), which are disposed opposite to each other on the two opposite walls of the storage slot (11).

8. A mask plate detection chuck according to any one of claims 1-6, characterized in that, The bottom of the storage trough (11) is through to form a detection port (113).

9. A mask plate detection chuck according to any one of claims 1-6, characterized in that, The substrate (1) has a plurality of clearance grooves (114) on one side, and each clearance groove (114) is connected to the storage groove (11).

10. A mask plate detection chuck according to any one of claims 1-6, characterized in that, The substrate (1) is coated with an antistatic plating layer.

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