Mechanical arm

Abstract

The embodiment of the utility model provides a mechanical arm which comprises a fixing structure used for fixing the mechanical arm to a machine table. The first side arm and the second side arm are located on the same side of the fixing structure, the first side arm is provided with at least one adsorption structure, the second side arm is provided with at least one adsorption structure, and the adsorption structures are used for adsorbing wafers; wherein the adsorption structure comprises an adsorption column and a suction cup located on the adsorption column, and a plurality of through holes are formed in the suction cup; the height of the suction column is adjusted based on the warping condition of the wafer, so that the suction cup can be attached to the wafer. According to the embodiment of the invention, the grabbing effect of the mechanical arm on the wafer can be improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, specifically to a robotic arm. Background Technology

[0002] In the complex process of integrated circuit manufacturing, wafers need to move between multiple different processing devices. In the semiconductor manufacturing field, wafer transfer is a critical step in the manufacturing process, requiring the safe and efficient transfer of wafers between various production stages. Robotic arms, as an important component of automated equipment, play a vital role in wafer transfer.

[0003] However, the current robotic arm's ability to grasp wafers still needs improvement. Utility Model Content

[0004] In view of this, embodiments of this application provide a robotic arm to improve the gripping effect of the robotic arm on wafers.

[0005] To achieve the above objectives, the embodiments of this application provide the following technical solutions.

[0006] This application provides a robotic arm, including:

[0007] A fixing structure is used to fix the robotic arm to the machine platform;

[0008] A first side arm and a second side arm are located on the same side of the fixing structure. The first side arm is provided with at least one adsorption structure, and the second side arm is provided with at least one adsorption structure. The adsorption structure is used to adsorb wafers.

[0009] The adsorption structure includes a suction column and a suction cup located on the suction column, the suction cup having several through holes; the height of the suction column is adjusted based on the warpage of the wafer so that the suction cup can fit against the wafer.

[0010] Optional, also includes:

[0011] The multispectral imaging device located in the fixed structure is used to scan the wafer, generate scanning results, and transmit the scanning results to the control system of the robotic arm so that the control system of the robotic arm can adjust the height of the suction column based on the scanning results; wherein, the scanning results are used to indicate the warping of the wafer.

[0012] Optionally, the multispectral imaging device includes: a complementary metal-oxide-semiconductor camera, a coaxial polarization light source, and a laser triangulation rangefinder.

[0013] Optionally, the through hole includes: a first through hole and a second through hole; wherein the first through hole is used for evacuating a vacuum, the second through hole is used for breaking the vacuum, and the diameter of the first through hole is smaller than the diameter of the second through hole.

[0014] Optionally, the number of the first through holes is greater than the number of the second through holes.

[0015] Optionally, the suction cup and the suction column are connected and fixed by a universal ball joint.

[0016] Optionally, the suction column is made of ceramic, and the ceramic includes at least piezoelectric ceramic.

[0017] Optionally, the suction cup is made of rubber.

[0018] Optionally, the diameter of the suction column ranges from 3 mm to 4 mm.

[0019] Optionally, the diameter of the suction cup ranges from 5 mm to 7 mm.

[0020] Compared with the prior art, the technical solution of this application has the following advantages:

[0021] This application provides a robotic arm, comprising: a fixing structure for fixing the robotic arm to a machine platform; a first side arm and a second side arm located on the same side of the fixing structure, wherein the first side arm is provided with at least one adsorption structure and the second side arm is provided with at least one adsorption structure, the adsorption structure being used to adsorb wafers; wherein, the adsorption structure includes a suction column and a suction cup located on the suction column, the suction cup being provided with a plurality of through holes; the height of the suction column is adjusted based on the warpage of the wafer so that the suction cup can fit against the wafer.

[0022] As can be seen, the robotic arm provided in this application embodiment can compensate for local warping of the wafer caused by manufacturing process or thermal stress (such as edge lifting or center depression) by dynamically adjusting the height of the suction column, so that the suction cup can better fit with the wafer, thereby realizing active compensation for wafer warping and improving the gripping effect of the robotic arm on the wafer. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1This is a top view schematic diagram of a robotic arm provided in an embodiment of this application;

[0025] Figure 2 This is a side view schematic diagram of a robotic arm provided in an embodiment of this application;

[0026] Figure 3 This is a schematic diagram of an optional structure of the suction cup provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] As the background technology indicates, in the complex process of integrated circuit manufacturing, wafers need to move between multiple different processing devices. In the semiconductor manufacturing field, wafer transfer is a critical step in the manufacturing process, requiring the safe and efficient transfer of wafers between various production stages. Robotic arms, as an important component of automated equipment, play a vital role in wafer transfer. However, the wafer-grabbing performance of robotic arms still needs improvement.

[0029] The inventors' analysis revealed that with the continuous evolution of integrated circuit chip manufacturing processes, the density of circuits integrated on wafers has significantly increased, and the stacked layer structure has become increasingly taller, leading to a more prominent wafer warpage problem. This phenomenon places higher demands on the performance of robotic arms when handling warped wafers. However, currently, when using adsorption-type vacuum robotic arms to grasp warped wafers, the uneven wafer surface easily causes vacuum leakage during the vacuum adsorption process, resulting in the suction cup not being able to fully adhere to the back of the wafer, thus severely affecting the robotic arm's grasping effect.

[0030] In view of this, this application provides a robotic arm, comprising: a fixing structure for fixing the robotic arm to a machine platform; a first side arm and a second side arm located on the same side of the fixing structure, wherein the first side arm is provided with at least one adsorption structure and the second side arm is provided with at least one adsorption structure, the adsorption structure being used to adsorb a wafer; wherein the adsorption structure includes a suction column and a suction cup located on the suction column, the suction cup being provided with a plurality of through holes; the height of the suction column is adjusted based on the warpage of the wafer so that the suction cup can fit against the wafer.

[0031] As can be seen, the robotic arm provided in this application embodiment can compensate for local warping of the wafer caused by manufacturing process or thermal stress (such as edge lifting or center depression) by dynamically adjusting the height of the suction column, so that the suction cup can better fit with the wafer, thereby realizing active compensation for wafer warping and improving the gripping effect of the robotic arm on the wafer.

[0032] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0033] refer to Figures 1-2 , Figure 1 This is a top view schematic diagram of a robotic arm provided in an embodiment of this application. Figure 2 This is a side view schematic diagram of a robotic arm provided in an embodiment of this application. Combined with... Figure 1 ,refer to Figure 2 The robotic arm may include:

[0034] The fixing structure 11 is used to fix the robotic arm to the machine platform.

[0035] The fixed structure 11 is the basic support component of the robotic arm, providing a stable mounting platform for other parts of the robotic arm (such as the side arms and suction structures). The fixed structure 11 secures the robotic arm to the machine base, ensuring it maintains the correct position and posture for accurate grasping and placement operations. The connection between the fixed structure 11 and the machine base is not achieved through permanent methods such as welding or riveting, but can be disassembled and reinstalled through reversible operations (such as loosening screws, pulling out pins, or unlocking clips). This detachability makes maintenance, component replacement, or upgrades of the robotic arm more convenient, eliminating the need for large-scale disassembly or modification of the entire device. Furthermore, the detachable fixing design allows the robotic arm to be quickly adjusted and optimized according to different production needs or process changes.

[0036] In some embodiments, the fixing structure 11 can be connected to the machine base using mechanical fasteners such as screws, bolts, and nuts. In other embodiments, the fixing structure 11 and the machine base can be designed with buckles and slots respectively, and the two are fixed by embedding the buckles into the slots. The buckle connection is quick to install and does not require additional tools. Disassembly only requires pressing the buckle or applying a certain external force to disengage the buckle from the slot.

[0037] A first side arm 21 and a second side arm 22 are located on the same side of the fixed structure 11. At least one adsorption structure 30 is provided on the first side arm 21 and at least one adsorption structure 30 is provided on the second side arm 22. The adsorption structure 30 is used to adsorb wafers.

[0038] Figure 1 Taking an example where two adsorption structures 30 are provided on the first side arm 21 and one adsorption structure 30 is provided on the second side arm 22, this embodiment demonstrates how the two adsorption structures 30 on the first side arm 21 and one adsorption structure 30 on the second side arm 22 can form a triangular adsorption point layout. This triangular layout reduces the risk of wafer deformation, slippage, or even detachment caused by excessive or uneven local forces, thereby enabling the robotic arm to better maintain wafer stability.

[0039] Understandably, due to Figure 2 This is a side view of the robotic arm, so from this perspective, it appears that there are two adsorption structures 30 on the second side arm 22, but in reality, there is only one adsorption structure 30 on the second side arm 22.

[0040] It should be noted that the two adsorption structures on the first side arm and the one adsorption structure on the second side arm are merely optional examples. In other embodiments, the number of adsorption structures on the first side arm and the number of adsorption structures on the second side arm can be set according to actual needs, and this application does not impose any limitations on this.

[0041] In a specific implementation, the adsorption structure 30 includes a suction column 31 and a suction cup 32 located on the suction column 31. The suction cup 32 is provided with a plurality of through holes 33 (e.g., ...). Figure 3 (as shown); the height of the suction column 31 is adjusted based on the warpage of the wafer so that the suction cup 32 can fit against the wafer.

[0042] In this embodiment, by dynamically adjusting the height of the suction column, local warping of the wafer caused by manufacturing process or thermal stress (such as edge lifting or center depression) can be compensated, so that the suction cup can better fit with the wafer, thereby achieving active compensation for wafer warping and improving the gripping effect of the robotic arm on the wafer.

[0043] In an optional implementation, the suction cup 32 and the suction column 31 can be connected and fixed using a universal ball joint. The universal ball joint connection allows the suction cup to be finely adjusted in multiple directions to accommodate wafers of different shapes and sizes, improving the adaptability and flexibility of the robotic arm. Specifically, the universal ball joint connection is a special mechanical connection method that allows two components (e.g., the suction cup and the suction column) to rotate relative to each other at multiple angles in three-dimensional space while maintaining a certain connection strength and stability. A universal ball joint typically consists of a ball head and a mating ball socket. The ball head can rotate freely within the ball socket, thus achieving multiple degrees of freedom in multiple directions.

[0044] Because wafers may warp or become uneven during manufacturing, the suction cup and the suction column are connected and fixed using a universal ball joint. This allows the suction cup to automatically adjust its angle when adsorbing the wafer, better conforming to the wafer surface and thus improving the adsorption effect. At the same time, the universal ball joint connection allows the suction cup to adhere more tightly to the back of the wafer, reducing vacuum leakage caused by loose adsorption and ensuring stable gripping of the wafer by the robotic arm.

[0045] In a specific implementation, the suction column 31 is made of ceramic, which includes at least piezoelectric ceramics. Piezoelectric ceramics are functional ceramic materials exhibiting the piezoelectric effect. The piezoelectric effect refers to the phenomenon where certain dielectrics, when deformed by an external force along a certain direction, develop internal polarization, resulting in opposite charges appearing on their two opposing surfaces; when the external force is removed, they return to an uncharged state. Conversely, when an electric field is applied in the polarization direction of the dielectric, it also deforms, and the deformation disappears when the electric field is removed. Specifically, the deformation can be controlled by applying voltage through a piezoelectric ceramic actuator. When voltage is applied to the piezoelectric ceramic, the internal crystal structure changes, causing minute changes in the ceramic's dimensions.

[0046] In optional implementations, the material of the suction column 31 may include, for example, zirconia-toughened ceramic and piezoelectric ceramic. In this embodiment, by selecting piezoelectric ceramic as the material of the suction column, it can be deformed by applying a voltage, thereby adjusting the height of the suction column. Specifically, the voltage causes the electric domains (i.e., small regions in the crystal with consistent spontaneous polarization directions) in the piezoelectric ceramic to turn or rearrange, thereby changing the overall polarization state and lattice structure of the ceramic. This change in lattice structure leads to the deformation of the ceramic.

[0047] In an optional implementation, the diameter of the suction column 31 ranges from 3 mm to 4 mm, for example, 3.5 mm. In robotic arms, the diameter of the suction column is limited by spatial layout. A smaller diameter helps to achieve a more compact design within a limited space, improving the integration and flexibility of the device. At the same time, the diameter of the suction column should not be too small, as this would prevent it from providing sufficient support and stability. Therefore, in this embodiment, the diameter of the suction column 31 ranges from 3 mm to 4 mm.

[0048] In an optional implementation, the suction cup 32 is made of rubber. Rubber has high flexibility, low hardness, high elasticity, and good sealing properties. Using rubber as the suction cup material allows for better adhesion to the wafer surface. The elastic deformation capability of rubber can effectively compensate for the microscopic unevenness of the wafer surface, ensuring uniform adsorption and no air leakage.

[0049] For example, the suction cup 32 is made of perfluoroether rubber. Perfluoroether rubber exhibits excellent resistance to almost all chemical reagents (including strong acids, strong alkalis, and organic solvents), enabling it to operate stably for extended periods in corrosive chemical environments used in wafer manufacturing, avoiding adsorption failure or contamination risks caused by material degradation. Simultaneously, perfluoroether rubber maintains stable physical and chemical properties within a temperature range of -25°C to 300°C, meeting the requirements of high-temperature processes in wafer fabrication (such as photolithography and etching), ensuring that the suction cup does not deform or harden at high temperatures, thus maintaining adsorption accuracy.

[0050] In an optional implementation, the diameter of the suction cup 32 ranges from 5 mm to 7 mm, for example, 6 mm. The diameter of the suction cup determines its contact area with the wafer. A larger diameter provides a larger adsorption area, thereby enhancing the adsorption force and ensuring the stability of the wafer during transport and processing. At the same time, the diameter of the suction cup should not be too large, as this will make the edge area of ​​the suction cup more prone to poor contact and leakage, thus compromising the vacuum seal. Therefore, in this embodiment, the diameter of the suction cup 32 ranges from 5 mm to 7 mm.

[0051] refer to Figure 3 An exemplary schematic diagram of an optional suction cup structure is shown. The through hole 33 may include: a first through hole 331 and a second through hole 332; wherein, the first through hole 331 is used for vacuuming, and the second through hole 332 is used for breaking the vacuum, and the diameter of the first through hole 331 is smaller than the diameter of the second through hole 332. For example, the diameter of the first through hole 331 may be 0.4 mm, and the diameter of the second through hole 332 may be 0.8 mm.

[0052] The first through-hole 331 can be connected to a vacuum pump or vacuum system to extract air between the chuck and the wafer, creating a vacuum environment that allows the wafer to be firmly adhered to the surface of the chuck. The second through-hole 332 is used to quickly release the vacuum between the chuck and the wafer, allowing the wafer to smoothly detach from the chuck and proceed to the next process step.

[0053] Because a stable vacuum needs to be established quickly during vacuuming, the diameter of the first through-hole 331 needs to be small enough to limit airflow, prevent overloading of the vacuum system, and ensure uniform distribution of adsorption force. Conversely, during vacuum breaking, external air needs to be introduced quickly to disrupt the vacuum environment; therefore, the diameter of the second through-hole 332 needs to be large enough to allow a large amount of air to enter rapidly, shortening the vacuum breaking time and improving efficiency.

[0054] In an optional implementation, the number of first through holes 331 is greater than the number of second through holes 332. Figure 3 Taking an example where there are three first through holes 331 and one second through hole 332, the following illustration is provided. When three first through holes are provided on the chuck for vacuuming, these three points will jointly form an adsorption plane, and three stable adsorption points will be formed on the wafer surface through vacuum adsorption force. These three adsorption points form a mechanical triangle in space, providing uniform and stable support for the wafer.

[0055] In an optional implementation, the robotic arm may further include:

[0056] The multispectral imaging device 12 located in the fixed structure 11 is used to scan the wafer, generate scanning results, and transmit the scanning results to the control system of the robotic arm so that the control system of the robotic arm can adjust the height of the suction column 31 based on the scanning results; wherein, the scanning results are used to indicate the warping of the wafer.

[0057] In one alternative implementation, before the robotic arm reaches into the front-opening-unified-pod (FOUP) to retrieve the wafer, a multispectral imaging module is triggered to scan the wafer, generating a three-dimensional deformation surface of the wafer. This three-dimensional deformation surface, used to indicate the wafer's warpage, is then presented as the scan result. The scan result is transmitted to the robotic arm's control system, which adjusts the height of the suction column based on the scan results. When the robotic arm reaches into the FOUP to retrieve the wafer, it first performs initial fine-tuning of the suction column of the adsorption structure based on the pre-generated three-dimensional deformation surface data. This ensures that the suction cups of the adsorption structure are as close as possible to the actual morphology of the wafer surface before contacting it, thereby reducing impact and slippage during contact.

[0058] If a discrepancy is found between the three-dimensional deformation surface data and the actual warping of the wafer during the actual contact between the robotic arm and the wafer (which may be due to scanning errors, slight movements of the wafer within the FOUP, etc.), the adsorption column of the adsorption structure can be fine-tuned again.

[0059] Once the adsorption structures are fully in contact with the wafer, a vacuum process is initiated to firmly attach the wafer to the robotic arm. After the wafer is fully held, the robotic arm retracts, removing the wafer from the FOUP and sending it to the machine for further processing or inspection.

[0060] In a specific implementation, the multispectral imaging device 12 may include: a complementary metal-oxide-semiconductor camera, a coaxial polarization light source, and a laser triangulation rangefinder.

[0061] Among them, the Complementary Metal-Oxide-Semiconductor (CMOS) camera is used to capture visible light images of the wafer surface, providing overall morphological information of the wafer.

[0062] Coaxial polarized light source: A light source used to provide a specific polarization state to enhance the contrast of specific features on the wafer surface (such as surface defects, textures, etc.) and improve imaging quality.

[0063] Laser triangulation rangefinder: Used to emit a laser beam and measure the angle change between the reflected light and the incident light to accurately calculate the height information of various points on the wafer surface.

[0064] In this embodiment, by combining image data from a CMOS camera, the enhancement effect of a coaxial polarized light source, and height data from a laser triangulation rangefinder, an algorithm is used to generate a three-dimensional deformation surface of the wafer. This surface can accurately reflect the warping, bending, and other deformations of the wafer.

[0065] As can be seen, the robotic arm provided in this application embodiment can compensate for local warping of the wafer caused by manufacturing process or thermal stress (such as edge lifting or center depression) by dynamically adjusting the height of the suction column, so that the suction cup can better fit with the wafer, thereby realizing active compensation for wafer warping and improving the gripping effect of the robotic arm on the wafer.

[0066] The foregoing describes multiple embodiment schemes provided by the embodiments of this application. The optional methods described in each embodiment scheme can be combined and cross-referenced with each other without conflict, thereby extending to a variety of possible embodiment schemes. These can all be considered as the embodiment schemes disclosed and published by the embodiments of this application.

[0067] While the embodiments disclosed above are described in this application, this application is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A robotic arm, characterized in that, include: A fixing structure is used to fix the robotic arm to the machine platform; A first side arm and a second side arm are located on the same side of the fixing structure. The first side arm is provided with at least one adsorption structure, and the second side arm is provided with at least one adsorption structure. The adsorption structure is used to adsorb wafers. The adsorption structure includes a suction column and a suction cup located on the suction column, the suction cup having several through holes; the height of the suction column is adjusted based on the warpage of the wafer so that the suction cup can fit against the wafer.

2. The robotic arm according to claim 1, characterized in that, Also includes: The multispectral imaging device located in the fixed structure is used to scan the wafer, generate scanning results, and transmit the scanning results to the control system of the robotic arm so that the control system of the robotic arm can adjust the height of the suction column based on the scanning results; wherein, the scanning results are used to indicate the warping of the wafer.

3. The robotic arm according to claim 2, characterized in that, The multispectral imaging device includes: a complementary metal-oxide-semiconductor camera, a coaxial polarization light source, and a laser triangulation rangefinder.

4. The robotic arm according to claim 1, characterized in that, The through hole includes: a first through hole and a second through hole; wherein the first through hole is used for evacuating a vacuum, the second through hole is used for breaking the vacuum, and the diameter of the first through hole is smaller than the diameter of the second through hole.

5. The robotic arm according to claim 4, characterized in that, The number of the first through holes is greater than the number of the second through holes.

6. The robotic arm according to claim 1, characterized in that, The suction cup and the suction column are connected and fixed by a universal ball joint.

7. The robotic arm according to claim 1, characterized in that, The suction column is made of ceramic, and the ceramic includes at least piezoelectric ceramic.

8. The robotic arm according to claim 1, characterized in that, The suction cup is made of rubber.

9. The robotic arm according to claim 1, characterized in that, The diameter of the suction column ranges from 3 mm to 4 mm.

10. The robotic arm according to claim 1, characterized in that, The diameter of the suction cup ranges from 5 mm to 7 mm.

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