Grinding machine arm and vacuum adsorption control method

Abstract

The invention relates to the technical field of transmission devices, in particular to a grinding machine arm and a vacuum adsorption control method, the grinding machine arm comprises an arm body comprising a first cavity and a second cavity, and a flat plate is provided with a plurality of through hole sites and air guide pipes; the suction nozzle comprises a pipe body and a convex edge, the pipe body is arranged outside the air guide pipe in an attached and sleeving mode, and the convex edge is located in the second cavity; the reset structure provides elastic force for the suction nozzle so as to be attached to the flat plate; through holes are formed in the side wall and the suction nozzles in a one-to-one correspondence mode, in the attached state, the end of the pipe body extends to be flush with or higher than the set distance from the through holes relative to the outer surface of the side wall, and the end of the air guide pipe retracts inwards relative to the end of the pipe body. The invention provides the grinding machine arm which can replace a film pasting belt ring to convey the wafer in the back adhesive film pasting process flow, the top of the ground wafer can be effectively adsorbed to drive the wafer to move, and the space size can be changed through movement of the suction nozzle relative to the air guide pipe to complete vibration buffering.

Description

Technical Field

[0001] The present invention relates to the technical field of transmission devices, and particularly to a grinding machine arm and a vacuum adsorption control method. Background Art

[0002] Wafer-level packaging (WLP), also known as wafer-level chip scale packaging (WLCSP), takes a wafer as the processing object, packages and tests chips on the wafer, and finally cuts them into individual devices, so that they can be directly attached to a substrate or a printed circuit board, while traditional packaging technologies take individual devices as the objects for packaging and testing.

[0003] In the wafer-level packaging process, by adopting a back glue film process, protection and strengthening can be provided for the back of the chip, and at the same time, light can be blocked to reduce the adverse effects of rays on the circuit surface. Compared with the traditional liquid resin coating process, making it into a tape shape can simplify the process flow, keep the thickness of the back protective layer uniform, and also reduce the thermal damage to the circuit by performing lamination at a lower temperature.

[0004] In the current back glue film attachment process flow, first, a thinning film is attached to the front of the wafer, and the wafer is thinned by a grinding machine. After the wafer is thinned, it is transferred to the film attachment process by a table to attach a cutting film, and then flows to the back glue film attachment station through a film attachment tape loop. At this station, the cutting film needs to be removed before attaching the back glue film, and then marking is performed and the cutting film is attached again to facilitate subsequent dicing and sorting.

[0005] In the above transmission process, the method of attaching and then removing the cutting film increases the material cost and labor cost. In this application, an attempt is made to change this method and develop a new transmission structure for transmitting the thinned wafer after grinding. Summary of the Invention

[0006] The present invention provides a grinding machine arm and a vacuum adsorption control method, aiming to solve the problems in the background art.

[0007] To achieve the above object, the technical solution of the present invention is as follows: A grinding machine arm includes: An arm body, including a first cavity and a second cavity which are stacked and separated by a flat plate. A plurality of through holes are distributed on the flat plate. On one side of the second cavity, air guide pipes are vertically arranged around each hole on the flat plate to communicate the first cavity with the outside of the grinding machine arm; A suction nozzle, including a pipe body and a flange extending around one end of the pipe body. The pipe body is fitted and sleeved outside the air guide pipe, and the flange is located in the second cavity; A reset structure is disposed on the side of the convex edge facing the tube body, between the side and the side wall of the arm body facing the side, providing an elastic force for the nozzle to fit with the flat plate; the side wall is arranged parallel to the flat plate, and through holes are provided corresponding to the nozzles one by one. In the fitting state, the end of the tube body extends from the through hole to be flush with or higher than the outer surface of the side wall by a set distance, and the end of the air guide tube is indented inward relative to the end of the tube body.

[0008] Further, a plurality of through air holes are provided on the side wall to communicate the second cavity with the outside of the grinding machine arm, and the aperture of the air holes is smaller than the aperture of the air guide tube.

[0009] Further, the first cavity and the second cavity are connected to the same vacuum system.

[0010] Further, the air guide tube and the flat plate are separately provided, and the connection is realized by means of threading or welding; or, the air guide tube and the flat plate are integrally formed.

[0011] Further, the nozzle is made of a polytetrafluoroethylene structure.

[0012] Further, the nozzle is a combined structure of polytetrafluoroethylene and rubber, and the rubber part is a sheet body and serves as the end of the tube body.

[0013] Further, the arm body includes three parts that are laminated and sealed, and the first cavity is formed between the first part and the second part, and the second cavity is formed between the second part and the third part.

[0014] Further, the reset structure is made of a rubber structure, sleeved around the tube body in a ring shape, or in a plurality of dispersed column shapes and fixedly connected to the convex edge.

[0015] A vacuum adsorption control method for the grinding machine arm as described above. After the grinding machine arm fits the nozzle with the wafer from the top of the wafer, evacuate the first cavity. After the vacuum degree is stable within the set range, move the grinding machine arm to transfer the wafer.

[0016] A vacuum adsorption control method for the grinding machine arm as described above. After the grinding machine arm fits the nozzle with the wafer from the top of the wafer, evacuate the first cavity and the second cavity synchronously. After the vacuum degrees of the two cavities are respectively stable within the corresponding set ranges, move the grinding machine arm to transfer the wafer; Or, first evacuate the first cavity, and after the vacuum degree is stable within the set range, move the grinding machine arm to transfer the wafer, and during the transfer process, selectively evacuate the second cavity as needed.

[0017] Through the technical solution of the present invention, the following technical effects can be achieved: In the present invention, a grinding machine arm is provided that can replace the film transfer belt loop to transfer wafers in the process of attaching the back adhesive film. It can effectively adsorb the top of the ground wafer and drive the wafer to move by transferring its own position after adsorption. After the grinding machine arm completes the adsorption of the wafer, during the transportation bumps, due to the elastic force provided by the reset structure for the suction nozzle, the negative pressure space can change the space size through the movement of the suction nozzle relative to the air duct to complete buffering, and the changed behavior can be terminated and reciprocated through the elastic reset of the reset structure. During the buffering process, since the amplitude of the space change is small, the influence ratio on the required vacuum degree for adsorption is small, and the situation of insufficient adsorption force will not occur. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a schematic structural diagram of the grinding machine arm; Figure 2 is Figure 1 a partial enlarged view of part A in Figure 3 It is an exploded view of the grinding machine arm; Figure 4 It is a partial schematic diagram of the position where the flat plate is set in the grinding machine arm; Figure 5 It is an optimized schematic diagram (partial section) of the grinding machine arm after setting air holes; Figure 6 is Figure 5 a partial enlarged view of part B in Figure 7 It is a schematic diagram of the process of the grinding machine arm adsorbing the wafer; Reference Signs: Reference Signs: 01, arm body; 011, first cavity; 012, second cavity; 013, flat plate; 014, air duct; 015, air hole; 016, side wall; 02, suction nozzle; 021, pipe body; 022, convex edge; 03, reset structure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0022] Embodiment 1

[0023] As Figures 1-6 shown, a grinding machine arm includes: An arm body 01, including a first cavity 011 and a second cavity 012 which are stacked and separated by a flat plate 013. A number of through holes are distributed on the flat plate 013. On one side of the second cavity 012, air guide pipes 014 are vertically arranged around each hole on the flat plate 013 to communicate the first cavity 011 with the outside of the grinding machine arm. A suction nozzle 02, including a pipe body 021 and a flange 022 extending around one end of the pipe body 021. The pipe body 021 is fitted and sleeved outside the air guide pipe 014, and the flange 022 is located in the second cavity 012. A reset structure 03 is arranged between the side surface of the flange 022 facing the pipe body 021 and the side wall 016 of the arm body 01 facing the side surface, providing an elastic force for the suction nozzle 02 to fit with the flat plate 013. The side wall 016 is parallel to the flat plate 013, and through holes are provided corresponding to the suction nozzles 02 one by one. In the fitting state, the end of the pipe body 021 extends from the through hole relative to the outer surface of the side wall 016 to be flush or a set distance higher, and the end of the air guide pipe 014 is indented inward relative to the end of the pipe body 021.

[0024] In the present invention, a structure is provided that can replace the transfer of wafers through a film transfer belt loop in the process of attaching a back adhesive film. Specifically, a grinding machine arm is provided, which can effectively adsorb the top of the ground wafer, and drive the wafer to move through the transfer of its own position after adsorption.

[0025] As a first implementation mode, the end of the tube body 021 extends from the through hole to be flush with the outer surface of the side wall 016. In this case, by moving the arm of the grinding machine, the side wall 016 of the arm body 01 and the end of the tube body 021 can be simultaneously attached to the top of the wafer. When there is sufficient vacuum in the first cavity 011, the wafer can be adsorbed. As a second implementation mode, the end of the tube body 021 extends from the through hole to be higher than a set distance relative to the outer surface of the side wall 016. The set distance here should not be too high, preferably between 0.5 and 2 mm. In this case, by moving the arm of the grinding machine, only the end of the tube body 021 can be attached to the top of the wafer. When there is sufficient vacuum in the first cavity 011, the wafer can also be adsorbed.

[0026] In the above two implementation modes of the present invention, the following functions can be achieved: After the grinding machine arm completes the adsorption of the wafer, the buffer for the vibration and bump during transportation can be achieved by the movement of the suction nozzle 02 relative to the air duct 014. Such vibration and bump include those visible to the naked eye and those that cannot be recognized by the naked eye. Specifically, regardless of which of the above implementation modes, after the suction nozzle 02 is attached to the wafer and the adsorption is completed, due to the action of the gravity of the wafer, the tube body 021 of the suction nozzle 02 will extend beyond the outer surface of the side wall 016 of the arm body 01, so that a buffer space is obtained for the buffering behavior. After the adsorption is completed, a negative pressure space with the same vacuum degree is formed inside the first cavity 011, inside the air duct 014, and inside the part of the tube body 021 that extends beyond the end of the air duct 014. During the transportation bumps, since the reset structure 03 provides an elastic force for the suction nozzle 02, the above-mentioned negative pressure space can change the space size through the movement of the suction nozzle 02 relative to the air duct 014 to complete the buffering, and the changed behavior can be terminated and reciprocated through the elastic reset of the reset structure 03.

[0027] During the buffering process, since the amplitude of the space change is small, the influence ratio on the vacuum degree required for adsorption is small, and the situation of insufficient adsorption force will not occur. The buffering achieved by the movement of the suction nozzle 02 can ensure that the adsorption position of the suction nozzle 02 fits more stably with the wafer.

[0028] In the above embodiment, the second cavity 012 is used as the installation space for the suction nozzle 02 and the reset structure 03. Preferably, it can also have the function of auxiliary adsorption, such as Figure 5 As shown: A number of through holes 015 are also provided on the side wall 016 to communicate the second cavity 012 with the outside of the grinding machine arm. The aperture of the through holes 015 is smaller than the aperture of the air duct 014.

[0029] Figure 5The situation where four groups are set and each group includes a number of relatively concentrated air holes 015 is shown. The above quantity is only shown as a specific implementation manner and does not limit the protection scope of the present invention. By setting the air holes 015 here, the second cavity 012 can obtain selectable functions. The first function is used as an installation space as described in the above embodiment, and the second function is to cooperate with the suction nozzle 02 to perform the suction action as an auxiliary suction position when the second cavity 012 also has a vacuum degree.

[0030] In this preferred solution, the timing for obtaining the vacuum degree in the second cavity 012 can be selected according to actual working needs, specifically including: Achieving synchronization with the vacuum degree imparted in the first cavity 011; Or, selectively opening at the required timing, such as: opening for a specific wafer that needs to improve the suction force, or opening for a production environment with special large vibration.

[0031] In order to reduce the implementation cost and facilitate the control of the vacuum degree, as a preference of the above embodiment, the first cavity 011 and the second cavity 012 are connected to the same vacuum system. Of course, in this way, the connection relationship between the two cavities and the vacuum system can be established separately through an independent pipeline structure, or the connection relationship between the two cavities and the vacuum system can be established synchronously through the same pipeline structure, which can be selected according to the actual usage mode and usage requirements, and all are within the protection scope of the present invention.

[0032] As a preference of the above embodiment, see Figure 3 and Figure 4 , the air duct 014 is separately arranged from the flat plate 013, and the connection is realized by means of threading or welding; or, the air duct 014 and the flat plate 013 are integrally formed.

[0033] In the present invention, the air duct 014 needs to realize the guiding function and the gas conduction function of the suction nozzle 02, and the above various setting methods can all realize the required structural relationship. In specific implementation, the threaded connection can be realized by setting an external thread at the end of the air duct 014 and an internal thread on the inner wall of the through hole.

[0034] In the above embodiments, the movement of the suction nozzle 02 relative to the air duct 014 is the key to achieving transportation buffering. To better implement this function, as a preference of the above embodiments, the suction nozzle 02 is made of polytetrafluoroethylene structure, and this material is easy to process the structural shape of the suction nozzle 02. After installation, the gap between the two can be sealed by the fitting of the pipe body 021 and the outer wall of the air duct 014. In the present invention, even a certain degree of leakage is allowed; for the seal between the outer wall of the pipe body 021 of the suction nozzle 02 and the inner wall of the through hole on the side wall 016 of the arm body 01, it is also achieved by the above fitting method. Similarly, even a certain degree of leakage is allowed.

[0035] In addition to the use of a single material, as another embodiment, the suction nozzle 02 is a combined structure of polytetrafluoroethylene and rubber. The rubber part is a sheet and serves as the end of the pipe body 021. Compared with the previous embodiment, the self-lubricating effect and structural form remain unchanged, but only a rubber sheet is provided at the adsorption and fitting position with the wafer. This method enables the end of the suction nozzle 02 to better adapt to the wafer to complete the adsorption function. In actual application scenarios, the wafer may have different degrees of deformation. Through the better elastic deformation ability of the rubber part compared with polytetrafluoroethylene, more stable and effective fitting can be ensured.

[0036] From the perspective of processing, installation and maintenance, as an optimized way of the arm body 01, as Figure 3 shown, the arm body 01 includes three parts that are laminated and sealed. A first cavity 011 is formed between the first part and the second part, and a second cavity 012 is formed between the second part and the third part. In this preferred solution, the three-part lamination method reduces the processing difficulty of each part, and it is also more convenient to install the internal structure of the second cavity 012; as a further preferred embodiment, the same method can be used for the fixation of the first part and the second part, and the fixation of the second part and the third part; specifically, it can be fixed by means of interference fit for hard extrusion and buckling, or, after the structures to be connected are aligned, it can be fixed by a penetrating connecting piece, both of which are within the protection scope of the present invention; the former can reduce the number of parts used, while the latter can make disassembly more convenient. Both have their own advantages and can be selected according to the actual situation. Of course, the above connection methods are only two specific embodiments in this scenario, and other methods that can achieve the purpose of the present invention are also within the protection scope of the present invention.

[0037] As a preference of the above embodiments, for the selection of the reset structure 03, there is the following optimized way. The reset structure 03 is a rubber structure and is sleeved around the pipe body 021 in a ring shape, Figure 3 and Figure 6This situation is shown in [Figure 0], and this is a relatively simple implementation method; alternatively, it is in the form of several scattered columns and is fixedly connected to the convex edge 022. The function achieved by this method is similar to that of the above embodiment, and it can be achieved by inserting the columnar reset structure 03 into the hole positions provided on the convex edge 022. In this way, when using the same rubber material, better elastic deformation ability can be obtained compared with the ring structure. Of course, sufficient support and reset ability need to be ensured through reasonable selection of materials and cross-sectional dimensions.

[0038] Embodiment 2

[0039] A vacuum adsorption control method for the grinding machine arm as described in Embodiment 1 is executed after the suction nozzle 02 is attached to the wafer from the top of the wafer by the grinding machine arm. The execution specifically includes: Vacuumize the first cavity 011, and after the vacuum degree is stable within the set range, move the grinding machine arm to transfer the wafer.

[0040] In this embodiment, the fitting standard can be set artificially, and the control of the specific fitting state can be achieved by collecting the fitting pressure between the suction nozzle 02 and the wafer and controlling this pressure. The pressure acquisition unit required here can be installed in many places in the prior art. For example, it can be set between the grinding machine arm and the frame structure for fixing it, and the pressure is fed back to the pressure acquisition unit through the whole grinding machine arm, or installed inside the grinding machine arm, such as between the convex edge 022 of the suction nozzle 02 and the flat plate 013, and the pressure is fed back to the pressure acquisition unit through the suction nozzle 02. Alternatively, the determination of the fitting state can also be achieved by controlling the moving distance of the grinding machine arm relative to the wafer, and all are within the protection scope of the present invention.

[0041] The following provides a detailed adsorption process as an example, as Figure 7 shown, including: S1: Control the grinding machine arm to approach the wafer from top to bottom. During the approaching process, continuously collect the pressure between the suction nozzle 02 and the wafer until the pressure reaches the set pressure threshold, and judge that the required fitting state is reached; S2: Turn on the vacuum system to vacuumize the first cavity 011, and stop vacuumizing when the vacuum degree reaches the set vacuum degree threshold; S3: Monitor the vacuum degree in the first cavity 011. After a set time, confirm that the vacuum degree is still within the set range, and execute step S4; the set time here can be 2 - 5 s, one limit value at one end of the set range can be the above vacuum degree threshold, and the other limit value can be specifically determined according to the selection of the set time and the length of the transmission path, etc.; S4: Control the movement of the grinding machine arm to drive the wafer to the set position.

[0042] Embodiment 3

[0043] A vacuum adsorption control method for the grinding machine arm as described in Embodiment 1. In this embodiment, different from Embodiment 2, a plurality of through holes 015 are further provided on the side wall 016. The vacuum adsorption control is executed after the suction nozzle 02 is attached to the wafer from the top of the wafer by the grinding machine arm. The specific execution is as follows: The first cavity 011 and the second cavity 012 are simultaneously evacuated. After the vacuum degrees of the two cavities are respectively stabilized within the corresponding set ranges, the grinding machine arm is moved to transfer the wafer; Or, first evacuate the first cavity 011, and after the vacuum degree is stabilized within the set range, move the grinding machine arm to transfer the wafer, and during the transfer process, selectively evacuate the second cavity 012 as needed.

[0044] In this embodiment, the determination of the attachment state is the same as that in Embodiment 2. By simultaneous evacuation, the suction nozzle 02 that plays a main adsorption role and the air holes 015 that play an auxiliary adsorption role can respectively achieve the adsorption effect, thus ensuring a more effective and stable adsorption. The simultaneous evacuation referred to in this embodiment includes two situations: starting and stopping simultaneously and starting simultaneously but not stopping simultaneously, both of which are within the protection scope of the present invention.

[0045] In this embodiment, when selectively evacuating the second cavity 012, the optional evacuation timing includes but is not limited to: The change in the transportation path angle exceeds the set range, the change in the transportation speed exceeds the set range, and the vibration amount of the grinding machine arm exceeds the set value. By executing the evacuation action of the second cavity 012, the effective adsorption of the wafer in the above situations can be ensured through the auxiliary adsorption effect.

[0046] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A grinding machine arm, characterized in that: include: The arm body comprises a first cavity and a second cavity which are stacked and separated by a plate, the plate is provided with a plurality of through holes, and an air duct is vertically provided around each hole on the plate on one side of the second cavity to connect the first cavity and the outside of the grinder arm; A nozzle, comprising a tube body and a convex edge extending from one end of the tube body to the surroundings, wherein the tube body is fitted and sleeved on the outside of the air guide tube, and the convex edge is located in the second cavity; A reset structure is arranged between the side of the convex edge facing the tube body and the side wall of the arm body facing the side, providing elastic force for the suction nozzle to fit with the flat plate; the side wall is arranged parallel to the flat plate, and through holes are arranged one by one corresponding to the suction nozzles. In the fitted state, the end of the tube body extends from the through hole to be flush with or higher than a set distance relative to the outer surface of the side wall, and the end of the air guide tube is retracted inward relative to the end of the tube body.

2. The grinding machine arm according to claim 1, characterized in that: The side wall is also provided with a plurality of through air holes to connect the second cavity with the outside of the grinder arm, and the aperture of the air holes is smaller than the aperture of the air guide tube.

3. The grinding machine arm according to claim 2, characterized in that: The first cavity and the second cavity are connected to the same vacuum system.

4. The grinding machine arm according to claim 1, characterized in that: The air duct and the flat plate are separately provided, and the connection is achieved by screw thread or welding; or, the air duct and the flat plate are integrally formed.

5. The grinding machine arm according to claim 1, characterized in that: The suction nozzle is a polytetrafluoroethylene structure.

6. The grinding machine arm according to claim 1, characterized in that: The suction nozzle is a composite structure of polytetrafluoroethylene and rubber, the rubber part is a sheet and serves as the end of the tube body.

7. The grinding machine arm according to claim 1, characterized in that: The arm body comprises three parts which are stacked and sealed, the first cavity is formed between the first part and the second part, and the second cavity is formed between the second part and the third part.

8. The grinder arm according to claim 1, characterized in that: The reset structure is a rubber structure, which is annularly sleeved on the periphery of the tube body, or is in the form of a plurality of dispersed columns and fixedly connected to the convex edge.

9. A vacuum adsorption control method for a grinding machine arm as claimed in claim 1, characterized in that: After the grinder arm attaches the suction nozzle to the wafer from the top of the wafer, the first cavity is evacuated, and after the vacuum degree is stabilized within a set range, the grinder arm is moved to transfer the wafer.

10. A vacuum adsorption control method for a grinding machine arm as claimed in claim 2, characterized in that: After the grinder arm attaches the suction nozzle to the wafer from the top of the wafer, the first cavity and the second cavity are simultaneously evacuated, and after the vacuum degrees of the two cavities are respectively stabilized within the corresponding set ranges, the grinder arm is moved to transfer the wafer; Alternatively, the first chamber is first evacuated, and after the vacuum degree is stabilized within a set range, the grinder arm is moved to transfer the wafer, and during the transfer process, the second chamber is selectively evacuated as needed.

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