A grinding machine arm and a vacuum adsorption control method

Abstract

The present invention relates to the technical field of transmission devices, and particularly to a grinding machine arm and a vacuum adsorption control method. The grinding machine arm includes: an arm body, which includes a first cavity and a second cavity, and a flat plate is distributed with a plurality of through holes and air ducts; a suction nozzle, which includes a pipe body and a flange, the pipe body is fittingly sleeved outside the air duct, and the flange is located in the second cavity; a reset structure, which provides an elastic force for the suction nozzle to fit with the flat plate; through holes are provided on the side walls corresponding to the suction nozzles one by one. In the fitting state, the end of the pipe 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 duct is indented inward relative to the end of the pipe body. In the present invention, a grinding machine arm is provided, which can replace the transmission of wafers through a film sticking belt loop in the back glue film attaching process flow, can effectively adsorb the top of the ground wafers to drive the wafers to move, and can change the space size by the movement of the suction nozzle relative to the air duct 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 complete packaging and testing with individual devices as the object.

[0003] In the wafer-level packaging process, by adopting a back adhesive 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 adhesive 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 adhesive film attachment station through a film attachment tape loop. At this station, the cutting film needs to be removed before attaching the back adhesive 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 tearing off 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 ground and thinned wafer. 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:

[0008] A grinding machine arm, comprising:

[0009] 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;

[0010] 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;

[0011] A reset structure is provided on the side of the convex edge facing the tube body, between the side wall of the arm body facing the side, to provide an 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 provided corresponding to the suction nozzles one by one. In the fitting state, the end of the tube body extends from the through hole to be flush or a set distance higher than the outer surface of the side wall, and the end of the air guide tube is indented inward relative to the end of the tube body.

[0012] Furthermore, a number 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.

[0013] Furthermore, the first cavity and the second cavity are connected to the same vacuum system.

[0014] Furthermore, the air guide tube and the flat plate are separately arranged, and the connection is realized by means of threading or welding; alternatively, the air guide tube and the flat plate are integrally formed.

[0015] Furthermore, the suction nozzle is made of polytetrafluoroethylene structure.

[0016] Furthermore, the suction nozzle is a combined structure of polytetrafluoroethylene and rubber. The rubber part is a sheet and serves as the end of the tube body.

[0017] Furthermore, the arm body includes three parts that are laminated and hermetically connected. 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.

[0018] Furthermore, the reset structure is made of rubber, is sleeved around the tube body in a ring shape, or is in the form of several scattered columns and is fixedly connected to the convex edge.

[0019] A vacuum adsorption control method for the grinding machine arm as described above. After the grinding machine arm fits the suction 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.

[0020] A vacuum adsorption control method for the grinding machine arm as described above. After the grinding machine arm fits the suction nozzle with the wafer from the top of the wafer, evacuate the first cavity and the second cavity simultaneously. 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;

[0021] Alternatively, first evacuate the first cavity, and after the vacuum degree is stabilized within the set range, move the grinder arm to transfer the wafer, and during the transfer process, selectively evacuate the second cavity as needed.

[0022] Through the technical solution of the present invention, the following technical effects can be achieved:

[0023] In the present invention, a grinder arm is provided that can replace the transfer of wafers through a film sticking tape loop in the process of attaching a back glue film. It can effectively adsorb the top of the ground wafer, and drive the wafer to move through the transfer of its own position after adsorption. After the grinder 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. Description of the Drawings

[0024] 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 to be used 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.

[0025] Figure 1 It is a schematic structural diagram of the grinder arm;

[0026] Figure 2 It is Figure 1 The partial enlarged view of part A in

[0027] Figure 3 It is an exploded view of the grinder arm;

[0028] Figure 4 It is a partial schematic diagram of the position where the flat plate is set in the grinder arm;

[0029] Figure 5 It is an optimized schematic diagram (partial section) of the grinder arm after setting air holes;

[0030] Figure 6 It is Figure 5 The partial enlarged view of part B in

[0031] Figure 7 It is a schematic diagram of the process of the grinder arm adsorbing the wafer;

[0032] Reference Signs:

[0033] Reference numerals: 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, flange; 03, reset structure. Specific embodiments

[0034] 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.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description 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.

[0036] Embodiment 1

[0037] As Figures 1-6 shown, a grinding machine arm includes:

[0038] 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 plurality of through holes are distributed on the flat plate 013. On one side of the second cavity 012, an air duct 014 is vertically arranged around each hole on the flat plate 013 to communicate the first cavity 011 with the outside of the grinding machine arm;

[0039] 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 duct 014, and the flange 022 is located in the second cavity 012;

[0040] A reset structure 03 is arranged between the side of the flange 022 facing the pipe body 021 and the side wall 016 of the arm body 01 facing the side, providing an elastic force for the suction nozzle 02 to fit with the flat plate 013; the side wall 016 is arranged 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 to be flush with or higher than the outer surface of the side wall 016 by a set distance, and the end of the air duct 014 is indented inward relative to the end of the pipe body 021.

[0041] In the present invention, a structure is provided that can replace the transfer of wafers through a film - sticking 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.

[0042] As a first implementation mode, the end of the pipe body 021 extends from the through - hole to be flush with the outer surface of the side wall 016. In this case, through the movement of the grinding machine arm, the side wall 016 of the arm body 01 and the end of the pipe 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 pipe 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 should not be too high, preferably between 0.5 and 2 mm. In this case, through the movement of the grinding machine arm, only the end of the pipe 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.

[0043] In the above two implementation modes of the present invention, the following functions can be achieved:

[0044] After the grinding machine arm adsorbs the wafer, it can buffer the vibration and bumps during transportation through the movement of the suction nozzle 02 relative to the air duct 014. Such vibration and bumps include those visible to the naked eye and those that cannot be recognized by the naked eye. Specifically, in either 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 wafer's gravity, the pipe 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 adsorption, 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 pipe body 021 that extends beyond the end of the air duct 014. During the transportation bumps, due to the elastic force provided by the reset structure 03 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 buffering, and the changing behavior can be terminated and reciprocated through the elastic reset of the reset structure 03.

[0045] During the buffering process, since the amplitude of the space change is small, the proportion of the impact on the required vacuum degree 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 a more stable fit between the adsorption position of the suction nozzle 02 and the wafer.

[0046] In the above - mentioned 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 5As shown, a plurality of through air holes 015 are further provided on the side wall 016 to communicate the second cavity 012 with the outside of the grinding machine arm. The aperture of the air holes 015 is smaller than that of the air duct 014.

[0047] Figure 5 The situation of setting four groups, with each group including a plurality of relatively concentrated air holes 015, is shown in . The above quantity is only shown as a specific implementation manner and does not limit the protection scope of the present invention. Through the setting of the air holes 015 here, the second cavity 012 can obtain selectable functions. The first function is as described in the above embodiment, used as an installation space, while the second function is that when the second cavity 012 also has a vacuum degree, it serves as an auxiliary adsorption position to cooperate with the suction nozzle 02 to perform the adsorption action.

[0048] In this preferred solution, the timing of obtaining the vacuum degree in the second cavity 012 can be selected according to actual working needs, specifically including:

[0049] Achieving synchronization with the vacuum degree given in the first cavity 011;

[0050] Or, selectively opening at the required timing, such as: opening for a specific wafer that needs to improve the adsorption force, or opening for a production environment with special large vibration.

[0051] 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.

[0052] As a preference of the above embodiment, see Figure 3 and Figure 4 , the air duct 014 is separately provided from the flat plate 013, and the connection is achieved by means of threading or welding; or, the air duct 014 and the flat plate 013 are integrally formed.

[0053] In the present invention, the air duct 014 needs to realize the guiding function of the suction nozzle 02 and the gas conduction function, and the above various setting methods can all achieve the required structural relationship. In specific implementation, the threaded connection can be achieved 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 position.

[0054] In the above embodiments, the movement of the 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 nozzle 02 is made of polytetrafluoroethylene structure, and it is easy to process the structural shape of the nozzle 02 with this material. 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; and the sealing between the outer wall of the pipe body 021 of the nozzle 02 and the inner wall of the through hole on the side wall 016 of the arm body 01 is also achieved by the above fitting method. Similarly, even a certain degree of leakage is allowed.

[0055] In addition to the use of a single material, as another embodiment, the 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 do not change, but only a rubber sheet is provided at the adsorption and fitting position with the wafer. This method can make the end of the nozzle 02 better adapt to the wafer to complete the adsorption function. In the actual application scenario, 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.

[0056] 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, for the fixation of the first part and the second part, and the fixation of the second part and the third part, the same method can be adopted; specifically, it can be fixed by hard extrusion and buckling through interference fit, or after the structures to be connected are aligned, they 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.

[0057] 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 , 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 the same rubber material is used, a 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.

[0058] Embodiment 2

[0059] 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:

[0060] Vacuum the first cavity 011. After the vacuum degree is stabilized within the set range, move the grinding machine arm to transfer the wafer.

[0061] In this embodiment, the fitting standard can be set artificially. 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 multiple 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, all within the protection scope of the present invention.

[0062] The following provides a detailed adsorption process as an example, as Figure 7 shown, including:

[0063] 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;

[0064] S2: Turn on the vacuum system to vacuum the first cavity 011, and stop vacuuming when the vacuum degree reaches the set vacuum degree threshold;

[0065] 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 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, the length of the transmission path, etc.;

[0066] S4: Control the movement of the grinder arm to drive the wafer to the set position.

[0067] Embodiment 3

[0068] A method for controlling the vacuum adsorption of the grinder arm as described in Embodiment 1. In this embodiment, different from Embodiment 2, a number 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 grinder arm. The specific execution is as follows:

[0069] Simultaneously evacuate the first cavity 011 and the second cavity 012. After the vacuum degrees of the two cavities are respectively stabilized within the corresponding set ranges, move the grinder arm to transfer the wafer;

[0070] Or, first evacuate the first cavity 011, and after the vacuum degree is stabilized within the set range, move the grinder arm to transfer the wafer, and during the transfer process, selectively evacuate the second cavity 012 as needed.

[0071] 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 the main adsorption role and the air holes 015 that play the auxiliary adsorption role can respectively achieve the adsorption effect, so as to ensure 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.

[0072] In this embodiment, when selectively evacuating the second cavity 012, the optional evacuation timing includes but is not limited to:

[0073] 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 grinder 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.

[0074] 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 claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A vacuum adsorption control method for a grinding machine arm, characterized in that, The 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 number 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 connect the first cavity and 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 fittingly sleeved outside the air guide pipe, and the flange is located in the second cavity; A reset structure, arranged between the side of the flange facing the pipe body and the side wall of the arm body facing the side, providing an 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 provided corresponding to the suction nozzles one by one. In the fitting state, the end of the pipe 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 pipe is indented inward relative to the end of the pipe body; A number of through air holes are also arranged on the side wall to connect the second cavity and the outside of the grinding machine arm. The aperture of the air holes is smaller than that of the air guide pipe; the arm body includes three parts which are stacked and hermetically connected. 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; The control method includes: After the grinding machine arm fits the suction nozzle with the wafer from the top of the wafer, the first cavity and the second cavity 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, 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 as needed.

2. The vacuum adsorption control method of the grinding machine arm according to claim 1, characterized in that The first cavity and the second cavity are connected to the same vacuum system.

3. The vacuum adsorption control method for the grinding machine arm according to claim 1, characterized in that The air guide pipe is separately arranged from the flat plate, and the connection is realized by means of threading or welding; or, the air guide pipe is integrally formed with the flat plate.

4. The vacuum adsorption control method for the grinding machine arm according to claim 1, characterized in that, The suction nozzle is made of polytetrafluoroethylene structure.

5. The vacuum adsorption control method for the grinding machine arm according to claim 1, wherein The suction nozzle is a combined structure of polytetrafluoroethylene and rubber. The rubber part is a sheet and serves as the end of the pipe body.

6. The vacuum adsorption control method of the grinding machine arm according to claim 1, characterized in that, The reset structure is made of rubber, sleeved around the pipe body in a ring shape, or in a number of scattered columns and fixedly connected to the flange.

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