High-precision chip mounting device with double elastic pieces

Abstract

The invention discloses a high-precision chip mounting device with double elastic pieces. The high-precision chip mounting device comprises a movable platform capable of moving in the z-axis direction, a rotation driving mechanism and an adsorption mechanism arranged on one side of the movable platform. The rotary driving mechanism is used for driving the adsorption mechanism to rotate; the adsorption mechanism comprises an adsorption shaft, a nut and a suction nozzle arranged at the bottom end of the adsorption shaft in a sleeving mode, the nut is arranged on the outer side of the adsorption shaft and rotationally connected with the movable platform, and the adsorption shaft can move in the nut along the z axis. The force control mechanism is mounted on the outer side of the adsorption mechanism and used for supporting and balancing the weight of the adsorption mechanism; and the guide mechanism is used for supporting the adsorption shaft to rotate and move. According to the invention, the acting force applied to the force control mechanism can be reduced, so that the stiffness coefficient k of the spring can be relatively smaller, the deformation of the spring is larger on the premise of achieving the same mounting force, the control difficulty of the force control precision can be further reduced, the frictional resistance is smaller during mounting, the mounting force of a mounting chip can be more accurately controlled, and the mounting precision of the mounting chip is improved. And the mounting quality is improved.

Description

Technical Field

[0001] The present application relates to the technical field of chip mounting, and in particular to a high-precision chip mounting device with double elastic parts. Background Art

[0002] During the chip mounting process, the chip is often a very delicate and fragile component. Therefore, the mounting force needs to be strictly controlled during the mounting process to avoid damage to the chip and ensure that the solder joints at the bottom of the chip can fully contact the pads on the substrate. This is of great significance for improving the reliability and stability of chip mounting. Especially in some applications that require extremely high chip quality, such as the packaging of high-frequency and high-power devices, it is even more necessary to strictly control the mounting force to protect the chip.

[0003] Different packaging forms and chips of different sizes have different requirements for chip placement force. Generally, as the chip size decreases, the requirements for force control become more stringent. Because small chips are more fragile, more sophisticated force control technology is required to ensure that they are not damaged during the placement process. If the placement force is too large or too small, it may cause chip damage, warping, dicing and other problems, thereby affecting the placement yield.

[0004] The existing patented technology of high-precision mounting force control device and force control method based on double elastic parts with publication number CN117936421A uses double elastic parts to realize force control of chip mounting. The rotation angle of the motor is determined by the number of pulses to control the distance change between the adjustment plate and the mounting plate, so as to obtain the set mounting force. It is not affected by the gravity of the welding head and has high control accuracy. However, the welding head and the visual mechanism are both located on the mounting plate, which will undoubtedly greatly increase the gravity acting on the double elastic parts, and often requires the use of The spring constant is relatively large. When the value is large, only a small amount of deformation is required to achieve the required mounting force. However, when mounting chips, it is difficult to accurately control the mounting force through a small amount of deformation, so it is more difficult to control the accuracy of chip mounting force. Summary of the invention

[0005] In view of the above defects, the present application provides a high-precision chip mounting device with double elastic parts, which can more easily control the force control accuracy, improve the mounting accuracy and quality, and adopt the following technical solutions: A double elastic member high-precision chip mounting device, comprising a movable platform, a rotation drive mechanism and an adsorption mechanism, wherein the movable platform can move along the z-axis direction, and the adsorption mechanism is arranged on one side of the movable platform for absorbing and mounting chips; The rotary drive mechanism is used to drive the adsorption mechanism to rotate; The adsorption mechanism includes an adsorption shaft and a nut, and a suction nozzle sleeved at the bottom end of the adsorption shaft for adsorbing the chip, the nut is arranged outside the adsorption shaft and is rotatably connected to the movable platform, and the adsorption shaft can move along the z-axis in the nut; A force control mechanism, which is arranged outside the adsorption mechanism and is used to support and balance the weight of the adsorption mechanism; The guide mechanism is sleeved on the outer side of the adsorption shaft and is used to support the rotation and movement of the adsorption shaft.

[0006] Preferably, the adsorption shaft comprises a rotating shaft and a guide shaft, the suction nozzle and the guide shaft are detachably connected to two ends of the rotating shaft respectively, and the guide mechanism is sleeved on the outside of the rotating shaft.

[0007] Preferably, the guide mechanism is an air bearing.

[0008] Preferably, the force control mechanism comprises a limit component, an upper elastic component and a lower elastic component which are sequentially sleeved on the outside of the guide shaft from top to bottom, and the upper elastic component and the lower elastic component are respectively provided between the movable platform, the limit component and the rotating shaft.

[0009] Preferably, it also includes a displacement detection component, and the displacement detection component is used to detect the displacement of the movable platform after the chip contacts the substrate.

[0010] Preferably, a rotating component is provided in the movable platform, and connecting components abutting against the upper elastic component and the lower elastic component are respectively provided on both sides of the rotating component.

[0011] Preferably, the rotary drive mechanism comprises a power component and a synchronous transmission assembly, and the synchronous transmission assembly is respectively connected to the driving end of the power component and the adsorption shaft.

[0012] Preferably, the outer side wall of the adsorption shaft is provided with at least one guide groove, and the guide groove extends along the axial direction of the adsorption shaft; and a plurality of rolling bodies capable of cyclically rolling along the guide groove are provided in the nut.

[0013] Preferably, an air passage is provided in the adsorption shaft, and the air passage is communicated with the suction nozzle.

[0014] Compared with the prior art, the beneficial effects of this application are: The present invention sets the force control mechanism on the outside of the adsorption mechanism, and the overall structure is compact, and the space occupied is relatively small, which can save more space; only the gravity of the adsorption mechanism will act on the force control mechanism, so that the force control mechanism can adopt a stiffness coefficient For elastic parts with relatively small values, under the premise of obtaining the same mounting force, by increasing the deformation of the elastic parts, that is, increasing the distance that the elastic parts need to be compressed, the difficulty of controlling the force control accuracy can be greatly reduced, thereby improving the force control accuracy.

[0015] Secondly, by cooperating with the force control mechanism, the friction resistance of the adsorption axis during mounting can be greatly reduced, making the adsorption mechanism more flexible in mounting chips, reducing the impact of friction resistance on the force control accuracy, and further improving the force control accuracy of mounting. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional schematic diagram of the present application; Figure 2 This is a schematic diagram of the normal state of this application; Figure 3 It is a schematic diagram of the chip of the present application contacting the substrate; Figure 4 This is a schematic diagram of the chip of the present application after the mounting force is applied.

[0017] In the figure: 1. Activity platform; 2. adsorption mechanism, 21. adsorption axis, 211. guide axis, 212. rotation axis; 3. force control mechanism, 31. upper elastic member, 32. lower elastic member; 4. Guide mechanism, 5. Rotation drive mechanism, 6. Connecting component, 7. Limiting component, 8. Rotating component. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described in the present application are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0019] See also Figure 1 and Figure 4 , further details of this application: A double elastic member high-precision chip mounting device comprises a movable platform 1, a rotation drive mechanism 5 and an adsorption mechanism 2, wherein the adsorption mechanism 2 is arranged on one side of the movable platform 1; the movable platform 1 can move along the z-axis to drive the adsorption mechanism 2 to mount the chip; wherein the movable platform 1 is driven by a longitudinal moving mechanism to move up and down along the z-axis, and the longitudinal moving mechanism can be arranged on the movable platform 1 on the side opposite to the adsorption mechanism 2, that is, on the movable platform 1 on the side away from the adsorption mechanism 2; the longitudinal moving mechanism can be a servo motor cooperating with a screw mechanism to realize the movement of the movable platform 1, and no limitation is made here.

[0020] The adsorption mechanism 2 includes an adsorption shaft 21, a nut and a suction nozzle. The suction nozzle is arranged at the bottom end of the adsorption shaft 21 and is used to pick up the chip; the nut is sleeved on the outside of the adsorption shaft 21 and is rotatably connected to the movable platform 1. The adsorption shaft 21 can move along the z-axis direction inside the nut; an air channel connected to the suction nozzle is provided inside the adsorption shaft 21.

[0021] The rotation driving mechanism 5 is disposed on the movable platform 1 and is used to drive the adsorption mechanism 2 to rotate, thereby controlling the chip mounting angle and improving the chip mounting accuracy.

[0022] A force control mechanism 3 and a guide mechanism 4 are also sleeved on the outside of the adsorption mechanism 2. The guide mechanism 4 is arranged on the movable platform 1 and is used to guide the movement and rotation of the adsorption shaft 21. In this embodiment, the guide mechanism 4 can be an air bearing, which can form an air film on the surface of the adsorption shaft 21 to reduce the friction resistance when the adsorption shaft 21 moves or rotates. The force control mechanism 3 connects the movable platform 1 and the adsorption mechanism 2, and is used to support and balance the weight of the adsorption mechanism 2 to reduce the influence of the gravity of the adsorption mechanism 2 on the mounting accuracy.

[0023] Combination Figure 2 In this embodiment, the suction shaft 21 includes a rotating shaft 212 and a guide shaft 211, the suction nozzle and the guide shaft 211 are detachably connected to the two ends of the rotating shaft 212, and the guide mechanism 4 is sleeved on the outside of the rotating shaft 212. The circular runout of the rotating shaft 212 during rotation is controlled by the guide mechanism 4, thereby ensuring the placement accuracy of the suction nozzle.

[0024] The force control mechanism 3 includes a limiting component 7, an upper elastic component 31 and a lower elastic component 32 which are sequentially sleeved on the outer side of the guide shaft 211 from top to bottom, the two ends of the upper elastic component 31 respectively abut the movable platform 1 and the limiting component 7, and the two ends of the lower elastic component 32 respectively abut the movable platform 1 and the rotating shaft 212. The upper elastic component 31 and the lower elastic component 32 are both springs; the limiting component 7 can be a clamp.

[0025] It also includes a displacement detection component, which is used to detect the displacement of the movable platform 1 after the suction nozzle contacts the substrate. The displacement detection component can be a displacement sensor, which can be arranged on the longitudinal moving mechanism, and a baffle is horizontally installed on the side of the movable platform 1, and the end of the displacement sensor abuts the bottom of the baffle; the position of the movable platform 1 on the longitudinal moving mechanism when the suction nozzle contacts the substrate is taken as the zero position, and the position of the displacement sensor on the longitudinal moving mechanism is adjusted, and when the suction nozzle sucks the chip and abuts the substrate, the end of the displacement sensor abuts the bottom of the baffle on the side of the movable platform 1, and when the suction nozzle abuts the substrate, the end of the displacement detection component abuts the movable platform 1 at the same time, thereby detecting the displacement of the movable platform 1; of course, the photoelectric sensor in CN117936421A can also be used.

[0026] According to Hooke's law ,in, is the stiffness coefficient, is the spring deformation.

[0027] In the prior art, the force applied to the elastic member (such as the gravity of the welding head and the visual mechanism) is very large. In order to achieve a balancing effect, a stiffness coefficient is required. Spring with large value; when the mounting force to be applied is constant, the stiffness coefficient The larger the value, the greater the deformation The smaller the motor, the more difficult it is to improve the resolution of the motor (motor control accuracy). , it is difficult to achieve precise control of the placement force. Therefore, it will make it more difficult to control the force control accuracy and require higher resolution of the motor.

[0028] Combination Figure 4 , the upper elastic member 31 and the lower elastic member 32 are both in a compressed state; assuming that the initial compression amount of the upper elastic member 31 is , the initial compression amount of the lower elastic member 32 is After the chip contacts the substrate, the displacement of the movable platform 1 detected by the displacement detection component is .

[0029] Combination Figure 2 , in static state, the adsorption mechanism 2 and the limiting component 7 thereon are taken as the force analysis objects. Under the influence of gravity, the weight of each component acts on the force control mechanism 3. At this time, the chip sucked by the nozzle does not contact the substrate, and the side of the lower elastic member 32 is balanced with the side of the lower elastic member 32, that is, ; The force direction on the left side of the equation is upward, and the force direction on the right side of the equation is downward. It is only the sum of the weights of the adsorption mechanism 2 and the limiting component 7, so the gravity acting on the force control mechanism 3 is small.

[0030] Combination Figure 3 When the suction nozzle abuts against the surface of the substrate, at this time, the adsorption mechanism 2 is in a stationary state, and the end of the displacement sensor abuts against the movable platform 1 synchronously.

[0031] Combination Figure 4 In the working state, the movable platform 1 continues to move downward to apply a mounting force to the chip. During this process, the compression amount of the upper elastic member 31 continues to decrease, that is, the length of the upper elastic member 31 becomes longer; the compression amount of the lower elastic member 32 continues to increase, that is, the length of the lower elastic member 32 becomes shorter; the mounting force applied to the chip will also continue to increase. When the movable platform 1 moves When the downward mounting force applied to the chip reaches the preset mounting force The adsorption axis 21 will be subjected to a reaction force equal in magnitude and opposite in direction to the mounting force. At this time, the compression amount of the upper elastic member 31 is , the compression amount of the lower elastic member 32 is , that is, , we can finally deduce That is, the displacement amount of the movable platform 1 detected by the displacement detection component is linearly related to the mounting force.

[0032] In the process of applying mounting force to the chip, the displacement of the movable platform 1 is is always smaller than the initial compression amount of the upper elastic member 31 Under the same mounting force requirement, if the prior art uses a spring with a smaller K value, the spring is more easily compressed, and a larger gravity is likely to cause the upper spring to be compressed together in the initial state, making it difficult to balance the weight of the adsorption mechanism 2.

[0033] The force control mechanism 3 of the present application only needs to balance the gravity of the adsorption mechanism 2, so the stiffness coefficient can be used. The value of the spring is relatively small. In this case, the deformation of the spring The spring deformation will also increase accordingly. Under the premise of the same mounting force, compared with the prior art, the present application increases the spring deformation by , which can provide more precise placement force for the chip, and the overall structure is more compact, and the space occupied is relatively small. Under the premise of the same resolution motor, the placement force control is more precise.

[0034] In order to prevent the upper elastic member 31 and the lower elastic member 32 from twisting when the adsorption mechanism 2 rotates, thereby affecting the accuracy of the control; a rotating component 8 is provided in the movable platform 1, and connecting components 6 are provided on both sides of the rotating component 8 to abut against the upper elastic member 31 and the lower elastic member 32. The connecting component 6 can be a gasket; the rotating component 8 can be a bearing, the outer ring of the rotating component 8 is connected to the movable platform 1, the connecting component 6 abuts against the inner ring of the rotating component 8, and the upper elastic member 31 and the lower elastic member 32 both abut against the connecting component 6; when the adsorption mechanism 2 rotates, the upper elastic member 31 and the lower elastic member 32 can rotate with the adsorption mechanism 2, thereby avoiding twisting.

[0035] There is a gap between the adsorption shaft 21 and the rotating component 8 and the connecting component 6, that is, the adsorption shaft 21 will not contact the rotating component 8 and the connecting component 6 during the rotation or movement process, so as to reduce friction resistance.

[0036] The rotary drive mechanism 5 includes a power component and a synchronous transmission assembly. The power component can be a motor. The synchronous transmission assembly is respectively connected to the driving end of the power component and the guide shaft 211. The synchronous transmission assembly is a pulley drive; a pulley is provided on the driving end of the power component and the nut and connected through a transmission belt. The pulley is sleeved on the outside of the nut. A tensioning component is also provided on the movable platform 1, and the tensioning component can tension the synchronous drive assembly.

[0037] The outer wall of the guide shaft 211 is provided with at least one guide groove, and the guide groove extends along the axial direction of the guide shaft 211; the nut is provided with a plurality of rolling bodies that can circulate and roll along the guide groove. During the movement of the guide shaft 211, the guide shaft 211 is supported and guided to move in the nut by the rolling bodies. Compared with the surface-to-surface contact sliding between the guide rail and the slider in the prior art, the friction resistance of the present application is smaller, which can further reduce the influence of the friction resistance of the guide shaft 211 during the movement on the force control accuracy during mounting, and can further improve the mounting accuracy. In this embodiment, the guide shaft 211, the rolling body and the nut can be a ball guide shaft structure.

[0038] In some embodiments, a connecting component is provided on the end of the adsorption shaft away from the suction nozzle for connecting to a vacuum generating device.

Claims

1. Double elastic parts high-precision chip mounting device, characterized by: It includes a movable platform, a rotation driving mechanism and an adsorption mechanism, wherein the movable platform can move along the z-axis direction, and the adsorption mechanism is arranged on one side of the movable platform for absorbing and mounting chips; The rotary drive mechanism is used to drive the adsorption mechanism to rotate; The adsorption mechanism includes an adsorption shaft and a nut, and a suction nozzle sleeved at the bottom end of the adsorption shaft for adsorbing the chip, the nut is arranged outside the adsorption shaft and is rotatably connected to the movable platform, and the adsorption shaft can move along the z-axis in the nut; A force control mechanism, which is arranged outside the adsorption mechanism and is used to support and balance the weight of the adsorption mechanism; A guide mechanism, which is sleeved on the outside of the adsorption shaft and is used to support the rotation and movement of the adsorption shaft; The suction shaft comprises a rotating shaft and a guide shaft, the suction nozzle and the guide shaft are detachably connected to the two ends of the rotating shaft respectively, and the guide mechanism is sleeved on the outside of the rotating shaft; The force control mechanism comprises a limiting component, an upper elastic component and a lower elastic component which are sequentially sleeved on the outer side of the guide shaft from top to bottom, and the upper elastic component and the lower elastic component are respectively provided between the movable platform, the limiting component and the rotating shaft.

2. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: The guide mechanism is an air bearing.

3. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: It also includes a displacement detection component, which is used to detect the displacement of the movable platform after the chip contacts the substrate.

4. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: A rotating component is arranged in the movable platform, and connecting components abutting against the upper elastic component and the lower elastic component are respectively arranged on both sides of the rotating component.

5. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: The rotary drive mechanism comprises a power component and a synchronous transmission assembly, and the synchronous transmission assembly is respectively connected to the driving end of the power component and the adsorption shaft.

6. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: The outer side wall of the adsorption shaft is provided with at least one guide groove, and the guide groove extends along the axial direction of the adsorption shaft; and a plurality of rolling bodies capable of cyclically rolling along the guide groove are provided in the nut.

7. The high-precision chip mounting device with double elastic members according to claim 1, characterized in that: An air passage is arranged in the adsorption shaft, and the air passage is communicated with the suction nozzle.

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