Vacuum chuck and manipulator

Abstract

A vacuum adsorption cavity and a pressure relief groove are formed in a chuck body of the vacuum chuck, an air hole communicated with the vacuum adsorption cavity is formed in one side of the chuck body, the other side of the chuck body is an adsorption face, and the pressure relief groove is located in the adsorption face and communicated with the vacuum adsorption cavity; the vacuum suction cup is further provided with an airtight structure, the airtight structure comprises an inflation state and a deflation state, the airtight structure protrudes towards the adsorption face side in the inflation state and cuts off communication between the pressure relief groove and the vacuum adsorption cavity, and the pressure relief groove is communicated with the vacuum adsorption cavity in the deflation state of the airtight structure. Through the arrangement of the pressure relief groove, the mirror surface effect caused by untimely vacuum release between the wafer and the adsorption surface is eliminated, the phenomena of wafer dragging and wafer jumping are reduced, and the wafer damage probability is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum adsorption, and in particular to a vacuum suction cup and a manipulator. Background Art

[0002] Wafers are generally transferred using a robot with a vacuum suction cup. However, after long-term use, the surface of the vacuum suction cup will become very smooth due to long-term friction with the wafer. After the vacuum pump connected to the vacuum suction cup is turned off, there is still a vacuum between the vacuum suction cup and the wafer, forming a mirror adsorption effect, causing the wafer to jump or be taken out of the wafer box, which may cause the wafer to be damaged or fall.

[0003] Currently, the common solution to this problem is to grind and replace the vacuum suction cup. Grinding eliminates the smooth mirror surface of the vacuum suction cup so that its surface smoothness can contact the wafer without damaging the wafer surface. However, long-term grinding will affect the service life of the vacuum suction cup and change the wafer picking position. After each grinding and replacement of the vacuum suction cup, a lot of time is required to re-correct the robotic arm's wafer picking / placing position, which is time-consuming and labor-intensive.

[0004] Therefore, it is necessary to develop a vacuum suction cup that does not require frequent grinding and replacement. Summary of the invention

[0005] The object of the present invention is to provide a vacuum suction cup and a robot arm, which are used to prevent the suction surface of the vacuum suction cup from being too smooth, resulting in a mirror suction effect between the vacuum suction cup and the wafer, and making it impossible to stably pick up and place the wafer.

[0006] The present invention provides a vacuum suction cup, wherein a vacuum suction chamber and a pressure relief groove are provided on the disc body of the vacuum suction cup, an air hole connected to the vacuum suction chamber is provided on one side of the disc body, and the other side of the disc body is a suction surface, the pressure relief groove penetrates the disc body in the radial direction of the vacuum suction chamber to connect the vacuum suction chamber with the outside of the disc body, and the pressure relief groove is provided with a notch on the suction surface; an airtight structure is also provided on the vacuum suction cup, and the airtight structure includes an inflated state and a deflated state, the airtight structure protrudes toward the suction surface side in the inflated state and is used for sealing contact with the object to be adsorbed to cut off the connection between the pressure relief groove and the vacuum suction chamber, and the airtight structure turns away from the suction surface in the deflated state and is used for moving away from the object to be adsorbed so that the pressure relief groove is connected to the vacuum suction chamber.

[0007] Preferably, a plurality of pressure relief grooves are arranged on the vacuum suction cup in an annular direction around the vacuum adsorption chamber.

[0008] Preferably, the width of the pressure relief groove on the adsorption surface gradually increases from the vacuum adsorption chamber side to the outer side of the disk body.

[0009] Preferably, the airtight structure includes an annular groove arranged around the vacuum adsorption chamber, and an air path placed in the annular groove and having an inflation and discharge port, the annular groove is communicated with the pressure relief groove, and the air path has a sealing portion protruding toward the adsorption surface side when in an inflated state, and the sealing portion is used to seal contact with the object to be adsorbed at the groove to isolate the pressure relief groove from being connected to the vacuum adsorption chamber.

[0010] Preferably, the sealing portion is an elastic member disposed in the annular groove, and the elastic member and the groove wall of the annular groove form the air path.

[0011] Preferably, the airtight structure includes an elastic member disposed in the pressure relief groove, and an inflation and deflation assembly for driving the elastic member to protrude.

[0012] Preferably, the inflation and deflation assembly comprises an air pipe with an inflation and deflation port, and the air pipe is sealed with the elastic member at the elastic member to form an inflation and deflation chamber.

[0013] Preferably, the body of the vacuum chuck is made of ceramic material.

[0014] The present invention also provides a robot arm, the end of which is provided with a vacuum suction cup as described in any one of the above items.

[0015] Preferably, the manipulator further comprises an air-charging and air-discharging device connected to the airtight structure, and the air-charging and air-discharging device is provided with a control mechanism for controlling the flow rate of the air-charging and air-discharging flow.

[0016] The vacuum suction cup and the manipulator of the present invention have the following beneficial effects: a pressure relief groove is provided on the suction surface of the vacuum suction cup, which penetrates the disc body along the radial direction of the vacuum suction chamber; the vacuum suction chamber is connected with the outside of the disc body through the pressure relief groove; an airtight structure is provided to achieve blocking and communication between the pressure relief groove and the vacuum suction chamber; thus, when sucking a wafer, the airtight structure is inflated to bulge toward the suction surface side so that the notch of the pressure relief groove can contact the object to be sucked, thereby cutting off the communication between the pressure relief groove and the vacuum suction chamber; as the vacuum suction chamber is evacuated, a vacuum is formed between the suction surface and the wafer. The vacuum suction cup is connected with the vacuum suction chamber, and the vacuum between the suction surface and the wafer is also broken as the vacuum suction chamber releases the vacuum. Thus, the setting of the pressure relief groove and the airtight structure eliminates the mirror effect caused by the untimely release of the vacuum between the wafer and the suction surface, reduces the occurrence of wafer dragging and wafer jumping, and reduces the probability of wafer damage. In addition, the vacuum suction cup does not need to be polished regularly, which reduces the maintenance time and improves the utilization efficiency of the robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a diagram of an embodiment of a vacuum chuck.

[0018] Figure 2 Shown is a cross-sectional view of a vacuum cup.

[0019] Figure 3 The diagram shows the vacuum chuck sucking the wafer.

[0020] Figure 4 Schematic diagram showing the state where the wafer is released from the vacuum chuck. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0022] like Figures 1 to 4 As shown, an embodiment of the present invention provides a vacuum suction cup, in which a vacuum suction chamber 102 and a pressure relief groove 101 are provided on the disc body 1 of the vacuum suction cup of this embodiment. In the thickness direction of the disc body, an air hole 104 connected to the vacuum suction chamber is provided on one side of the disc body 1, and the other side of the disc body 1 is a suction surface; the pressure relief groove 101 penetrates the disc body 1 in the radial direction of the vacuum suction chamber 102 to connect the vacuum suction chamber 102 with the outside of the disc body, and the pressure relief groove 101 is provided with a notch on the suction surface; an airtight structure 2 is also provided on the vacuum suction cup, and the airtight structure 2 can be switched between an inflated state and a deflated state. When in the inflated state, the airtight structure 2 protrudes toward the suction surface side and is used for sealing contact with the object to be adsorbed to cut off the connection between the pressure relief groove 101 and the vacuum suction chamber 102. When in the deflated state, the airtight structure 2 turns away from the suction surface and is used to stay away from the object to be adsorbed so that the pressure relief groove 101 is connected to the vacuum suction chamber 102. In this embodiment, the disk body 1 is provided with a pressure relief groove 101, which has a notch on the adsorption surface and radially penetrates the disk body along the vacuum adsorption chamber 102, that is, the vacuum adsorption chamber 102 and the space outside the disk body can be communicated through the pressure relief groove 101, the adsorption surface of the disk body 1 is separated by the notch, and the airtight structure can achieve the sealing and communication between the pressure relief groove 101 and the vacuum adsorption chamber 102 at the notch.

[0023] In this embodiment, the object to be adsorbed is a wafer, or a silicon chip. Figure 3As shown, when the vacuum suction cup sucks the wafer 3, air is inflated through the airtight structure until the airtight structure at the pressure relief groove 101 protrudes the suction surface from the notch, and as the vacuum suction chamber 102 is evacuated, the wafer 3 is pressed on the airtight structure at the notch, and then the airtight structure is in sealed contact with the wafer, so that a vacuum is formed between the suction surface of the plate body 1 and the wafer 3; see Figure 4 As shown, when releasing the wafer 3, it is only necessary to control the airtight structure to deflate, the vacuum adsorption chamber is stopped from being evacuated, and the airtight structure at the pressure relief groove 101 is lower than the adsorption surface, so that the atmosphere outside the disk body can flow to the vacuum adsorption chamber 102, breaking the vacuum between the adsorption surface of the disk body 1 and the wafer 3. Therefore, the setting of the pressure relief groove 101 and the airtight structure eliminates the mirror effect caused by the untimely vacuum release between the wafer 3 and the adsorption surface, reduces the occurrence of wafer dragging and wafer jumping, and reduces the probability of wafer damage; in addition, the vacuum suction cup does not need to be polished regularly, which reduces the maintenance time and improves the utilization efficiency of the robot.

[0024] For ease of explanation, in this embodiment, the groove depth direction of the pressure relief groove 101 is the thickness direction of the disc body 1, and its groove depth is the depth of the downward depression from the adsorption surface of the disc body 1; the groove length of the pressure relief groove 101 is the length penetrating the disc body along the radial direction of the vacuum adsorption cavity. In the groove length direction of the pressure relief groove, one end of the pressure relief groove 101 extends into the vacuum adsorption cavity 102, and the other end extends to the outside of the disc body. Specifically, the cavity wall of the vacuum adsorption cavity 102 may have a channel that constitutes a part of the pressure relief groove 101; the groove width of the pressure relief groove 101 is the circumferential dimension of the disc body. The arrangement of the above-mentioned airtight structure not only separates the vacuum adsorption chamber from the outside of the disc body in the groove length direction of the pressure relief groove when it is inflated, but also contacts with the object to be adsorbed so that the disc body and the object to be adsorbed form a closed space. The closed space forms a vacuum environment as the vacuum adsorption chamber is evacuated, thereby achieving the adsorption of the object to be adsorbed. When the airtight structure is deflated, it moves away from the object to be adsorbed and then connects the vacuum adsorption chamber with the outside of the disc body in the groove length direction of the pressure relief groove. The closed space formed by the disc body and the object to be adsorbed is destroyed, and the vacuum of the vacuum adsorption chamber is released to achieve the release of the object to be adsorbed.

[0025] In order to better facilitate the release of the wafer, in this embodiment, a plurality of pressure relief grooves 101 are arranged circumferentially around the vacuum adsorption chamber 102 on the vacuum suction cup. Specifically, at least four pressure relief grooves 101 are evenly distributed in the circumferential direction on the disc body 1. All the pressure relief grooves 101 can evenly divide the adsorption surface in the circumferential direction, which is further convenient for eliminating the vacuum adsorption between the adsorption surface and the wafer. The slot width of each pressure relief groove 101 on the adsorption surface gradually increases from the vacuum adsorption chamber side to the outside of the disc body, which is convenient for the atmosphere to enter the pressure relief groove 101 from the outside of the disc body. The reduced slot width can increase the gas flow rate and timely destroy the adsorption force between the airtight structure and the wafer. The atmosphere enters the vacuum adsorption chamber in time, which can further eliminate the mirror effect caused by the untimely release of the vacuum between the wafer 3 and the adsorption surface. The groove depth of the pressure relief groove 101 can be the same as the thickness of the disc body 1, that is, the thickness that passes through the disc body 1, or it can be half of the thickness of the disc body, or less than half of the thickness of the disc body. The pressure relief grooves 101 of this embodiment may be fan-shaped, strip-shaped, grid-shaped, or radial. The shape and size of the pressure relief grooves 101 are not limited thereto, and the size and shape of the pressure relief grooves can be designed through fluid mechanics testing and calculation of the adsorption force of the disk. The groove width of each pressure relief groove 101 may be consistent or inconsistent in the groove depth direction. For better pressure relief, in a preferred embodiment, the groove width of the pressure relief groove 101 may gradually decrease from the above-mentioned notch downward, so that the flow of the atmosphere is more concentrated on the side close to the adsorption surface, that is, flowing at the notch. A plurality of pressure relief grooves 101 are evenly arranged in an annular direction, and in the side view of the disk, each pressure relief groove 101 is arranged like a sawtooth, so that the adsorption surface is more evenly separated, which further facilitates breaking the vacuum environment between the adsorption surface and the wafer.

[0026] As an embodiment of the above-mentioned airtight structure, see Figure 1 and Figure 2 As shown, the airtight structure 2 in this embodiment includes an annular groove 22 arranged around the vacuum adsorption chamber 102 in the disc body, and an air path placed in the annular groove 22 and having an air filling and discharging port. The annular groove is connected to the pressure relief groove 101, and the air path has a sealing portion 21 that protrudes toward the adsorption surface side in the inflated state to cut off the communication between the pressure relief groove 101 and the vacuum adsorption chamber 102. The air path in this embodiment is arranged around the vacuum adsorption chamber 102 along with the annular groove. The sealing portion 21 can be arranged only at the pressure relief groove, or can be arranged along the air path for a circle. It is not limited here. It only needs to be possible to achieve that the sealing portion 21 protrudes toward the adsorption surface side and then protrudes out of the above-mentioned notch to make sealing contact with the wafer when the air path is in the inflated state, thereby cutting off the communication between the pressure relief groove 101 and the vacuum adsorption chamber 102; the sealing portion 21 is away from the adsorption surface when the air path is in the deflated state, and is recessed at the notch to break the contact with the wafer, so that the pressure relief groove is connected to the vacuum adsorption chamber. In this embodiment, the sealing portion 21 is raised and sunken by inflating and deflating the gas path, thereby achieving the sealed separation and communication between the pressure relief groove 101 and the vacuum adsorption chamber 102, and thus achieving the wafer absorption. Figure 3As shown, the air path inflated sealing portion 21 bulges toward the adsorption surface until it contacts the wafer, thereby blocking the pressure relief groove 101 from communicating with the vacuum adsorption chamber 102, so that a vacuum environment is formed between the wafer 3 and the adsorption surface to adsorb the wafer 3; see Figure 4 As shown, as the vacuum adsorption chamber 102 releases the vacuum, the gas path is deflated, and the sealing portion 21 is sunken in the pressure relief groove 101 below the adsorption surface. The atmosphere can enter the vacuum adsorption chamber 102 from the notch side of the pressure relief groove 101, dividing the adsorption surface circumferentially, eliminating the vacuum environment between the wafer and the adsorption surface, and avoiding the mirror adsorption effect. The gas path of this embodiment can be an independent pipeline or integrated with the annular groove.

[0027] As an embodiment, the sealing portion 21 is an elastic member arranged in the annular groove, and the elastic member 21 and the groove wall of the annular groove 22 form an air path. The elastic member can be an elastic rubber mold, or other materials with elastic and sealable cavities. The elastic member can be directly pasted and fixed in the annular groove 22, or it can be pressed in the annular groove 22 through a fixed structure such as a limit ring. The elastic member goes around the vacuum adsorption chamber with the annular groove 22. The fixing method of the elastic member is not limited. It only needs to be sealed and connected to the groove wall of the annular groove 2 to be used as an air path. Specifically, when the air path is inflated, the elastic member protrudes toward the adsorption surface side and protrudes out of the adsorption surface. The elastic members circumferentially around the vacuum adsorption chamber are in contact with the wafer, and then the disk and the wafer form a vacuum environment during the vacuum adsorption chamber being evacuated. The elastic member can also be directly composed of the tube wall constituting the gas path, such as placing a hose in the annular groove, the cross section of which can be a circle, an ellipse, or other shapes that adapt to the annular groove; in the length direction of the hose, the tube wall of the hose corresponding to the pressure relief groove is a convex elastic membrane, or the tube wall of the hose facing the adsorption surface is an elastic membrane; the end of the hose is the above-mentioned charging and discharging port, which can be connected to the gas source and the exhaust structure. When inflating, the elastic membrane bulges toward the adsorption surface side as the air pressure in the hose increases, until it contacts the wafer at the notch to seal and block the pressure relief groove 101 and the vacuum adsorption chamber 102, so that a vacuum environment is formed between the wafer and the disk body, that is, the wafer is adsorbed; when releasing the wafer, the hose is exhausted, and as the air pressure in the hose decreases, the elastic membrane recovers and is lower than the adsorption surface at the notch, the pressure relief groove 101 and the vacuum adsorption chamber 102 are restored to communicate, and the atmosphere enters between the wafer and the disk body to eliminate the vacuum, so as to achieve timely and stable release of the wafer.

[0028] As another embodiment of the airtight structure, the airtight structure includes an elastic member disposed in the pressure relief groove 101, and an air charging and discharging assembly (not shown) that drives the elastic member to protrude. Preferably, the air charging and discharging assembly includes an air pipe with an air charging and discharging port, and the air pipe is sealed with the elastic member at the elastic member to form an air charging and discharging chamber. If the elastic member is sealed and fixed in the pressure relief groove, the groove depth of the pressure relief groove is less than the thickness of the disk body, that is, the pressure relief groove does not penetrate the thickness direction of the disk body, and the elastic member can form an air charging and discharging chamber connected to the air pipe with the bottom of the pressure relief groove. Alternatively, the elastic member is directly connected to the air pipe in a sealed manner and then embedded in the pressure relief groove. When the air pipe is inflated, the elastic member expands to protrude the above-mentioned notch and contact the wafer to seal and block the communication between the pressure relief groove 101 and the vacuum adsorption chamber 102. In this embodiment, the air pipe can be one, or one can be set for each pressure relief groove. It is not limited here, as long as it can realize synchronous air charging and discharging. The elastic member of this embodiment can be an elastic rubber mold, or other materials with elastic and sealable cavities. The air pipe in this embodiment can be formed by punching holes directly on the disc body, or can be a hose fixed on the disc body, which is not limited here.

[0029] In order to better absorb and release the wafer, the plate body of the above-mentioned vacuum suction cup is made of ceramic material.

[0030] The present invention also provides a manipulator, the end of the manipulator is provided with a vacuum suction cup as described above, and the vacuum suction cup of this embodiment can be detachably arranged at the end of the manipulator, or can be integrated with the end of the manipulator. The vacuum suction cup of this embodiment prevents the problem of mirror suction effect with the wafer due to the too smooth suction surface caused by long-term use, and therefore does not need to be replaced and maintained regularly, thereby improving the use efficiency of the manipulator and saving production costs.

[0031] More preferably, the manipulator also includes an inflation and deflation device connected to the airtight structure, and the inflation and deflation device is provided with a control mechanism for controlling the inflation and deflation flow rate. The control mechanism can realize precise control of inflation and deflation, ensuring that sufficient air pressure is reached during inflation so that the elastic member is fully raised to cut off the connection between the pressure relief groove 101 and the vacuum adsorption chamber 102. In an embodiment where there are multiple pressure relief grooves, the control mechanism can ensure that the elastic members at the multiple pressure relief grooves are synchronously restored to the initial state, so that the pressure relief groove 101 is connected with the vacuum adsorption chamber 102.

[0032] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A vacuum suction cup, characterized in that: The disc body of the vacuum suction cup is provided with a vacuum adsorption chamber and a pressure relief groove, one side of the disc body is provided with an air hole connected with the vacuum adsorption chamber, and the other side of the disc body is a suction surface, the pressure relief groove penetrates the disc body in the radial direction of the vacuum adsorption chamber to connect the vacuum adsorption chamber with the outside of the disc body, and the pressure relief groove is provided with a notch on the adsorption surface; the vacuum suction cup is also provided with an airtight structure, and the airtight structure switches between an inflated state and a deflated state. When in the inflated state, the airtight structure protrudes toward the adsorption surface side and is used for sealing contact with the object to be adsorbed, thereby isolating the connection between the pressure relief groove and the vacuum adsorption chamber, and when in the deflated state, the airtight structure turns away from the adsorption surface and is used to stay away from the object to be adsorbed so that the pressure relief groove is connected with the vacuum adsorption chamber.

2. The vacuum suction cup according to claim 1, characterized in that: A plurality of pressure relief grooves are arranged on the vacuum suction cup in an annular direction around the vacuum adsorption chamber.

3. The vacuum suction cup according to claim 1 or claim 2, characterized in that: The width of the pressure relief groove on the adsorption surface gradually increases from the vacuum adsorption chamber side to the outside of the disk body.

4. The vacuum suction cup according to claim 1, characterized in that: The airtight structure includes an annular groove arranged around the vacuum adsorption chamber, and an air path placed in the annular groove and having an air charging and discharging port. The annular groove is connected to the pressure relief groove, and the air path has a sealing portion that protrudes toward the adsorption surface side when in an inflated state. The sealing portion is used to seal and contact with the object to be adsorbed at the groove to isolate the pressure relief groove from the vacuum adsorption chamber.

5. The vacuum suction cup according to claim 4, characterized in that: The sealing portion is an elastic member arranged in the annular groove, and the elastic member and the groove wall of the annular groove form the gas path.

6. The vacuum suction cup according to claim 1, characterized in that: The airtight structure includes an elastic member arranged in the pressure relief groove, and an inflation and deflation assembly driving the elastic member to bulge.

7. The vacuum suction cup according to claim 6, characterized in that: The inflation and deflation assembly comprises an air pipe with an inflation and deflation port, and the air pipe is sealed with the elastic member at the elastic member to form an inflation and deflation chamber.

8. The vacuum suction cup according to claim 1, characterized in that: The plate body of the vacuum suction cup is made of ceramic material.

9. A robot, characterized in that: The end of the robot is provided with a vacuum suction cup as described in any one of claims 1 to 8.

10. The robot according to claim 9, characterized in that: The manipulator also includes an air-filling and air-discharging device connected to the airtight structure, and the air-filling and air-discharging device is provided with a control mechanism for controlling the flow rate of the air-filling and air-discharging flow.

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