Chip attitude adaptive bonding mechanism, method and system with precise force control

Abstract

The invention discloses a chip posture self-adaptive bonding mechanism with precise force control, a method and a system. The chip posture self-adaptive bonding mechanism with the precise force control function comprises a constant force mechanism, a rapid feeding driving device and a micro-motion device. The constant force mechanism comprises a positive stiffness mechanism, a negative stiffness mechanism, a first output piece and a second output piece, and the second output piece is movably arranged on the first output piece and has a relative displacement value; the positive rigidity mechanism and the negative rigidity mechanism are connected in parallel so that the output force of the second output piece within the preset relative displacement range can be constant. The fast feed driving device is used for driving the constant force mechanism to move in the first direction, and the micro-motion device is used for driving the first output piece to move in the first direction; and when the relative displacement value is within the preset relative displacement range, the micro-motion device is turned on, and the rapid feed driving device is turned off. The constant bonding force can be provided, the control precision of the bonding force and the stability of the bonding force are improved, the control process of chip bonding is simplified, and the efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and particularly to a chip attitude adaptive bonding mechanism, method, and system with precise force control. Background Art

[0002] In the chip bonding and packaging technology, low-precision bonding force control will reduce the reliability of chip interconnection, resulting in a decrease in the yield rate of chip products. Before flip-chip bonding, the linear motor is position-controlled to quickly move the chip near the substrate; when the solder balls on the chip contact the substrate, the linear motor is controlled to perform force / position switching, that is, the linear motor switches from the fast feed state to the low-speed output state and stably outputs the bonding force.

[0003] However, when the linear motor performs force / position switching, an inevitable force overshoot phenomenon will occur at the output end, reducing the control accuracy of the bonding force and resulting in unstable bonding force, thereby affecting the quality of chip bonding and even causing chip bonding failure. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, an object of the present invention is to provide a chip attitude adaptive bonding mechanism with precise force control, which can provide a constant bonding force, reduce the influence of force overshoot on chip packaging, improve the control accuracy of the bonding force and the stability of the bonding force, simplify the control process of chip bonding, and improve the efficiency of chip bonding and packaging.

[0005] The present invention also provides a chip attitude adaptive bonding method with precise force control.

[0006] The present invention also provides a chip attitude adaptive bonding system with precise force control.

[0007] An embodiment of the first aspect of the present invention provides a chip attitude adaptive bonding mechanism with precise force control, including a constant force mechanism, a rapid feed driving device, and a fine motion device. The constant force mechanism includes a positive stiffness mechanism, a negative stiffness mechanism, a first output member, and a second output member. The second output member is movably disposed on the first output member and is used to connect the bonding head. The second output member has a relative displacement value in a first direction relative to the first output member. The positive stiffness mechanism and the negative stiffness mechanism are installed in parallel between the first output member and the second output member to make the output force of the second output member constant within a preset relative displacement range. The rapid feed driving device is used to drive the constant force mechanism to move in the first direction, and the rapid feed driving device is configured to be turned off when the relative displacement value of the second output member is within the preset relative displacement range. The fine motion device is used to drive the first output member to move in the first direction, and the fine motion device is configured to be turned on when the relative displacement value of the second output member is within the preset relative displacement range.

[0008] In some embodiments, the chip attitude adaptive bonding mechanism with precise force control further includes a dynamic strain measurement component and a control device. The dynamic strain measurement component is used to obtain the strain signals of the positive stiffness mechanism and / or the negative stiffness mechanism. The control device is electrically connected to the rapid feed driving device, the fine motion device, and the dynamic strain measurement component respectively. The control device is used to convert the strain signals into the relative displacement value of the second output member. The control device is further used to control the operating states of the rapid feed driving device and the fine motion device.

[0009] In some embodiments, the control device further includes a comparison module. The comparison module is used to compare the relative displacement value with the preset relative displacement range. The preset relative displacement range has a minimum end value. When the relative displacement value is between zero and the minimum end value, the fine motion device is turned on. When the relative displacement value is the minimum end value, the rapid feed driving device is turned off.

[0010] In some embodiments, the dynamic strain measurement component includes strain gauges disposed on the positive stiffness mechanism and / or the negative stiffness mechanism.

[0011] In some embodiments, the positive stiffness mechanism is configured as a positive stiffness beam structure, and the negative stiffness beam is configured as a negative stiffness beam structure.

[0012] In some embodiments, an insertion slot extending in the first direction is formed on the first output member, and the second output member is disposed in the insertion slot.

[0013] In some embodiments, a positive stiffness mechanism installation cavity and a negative stiffness mechanism installation cavity are further formed on the first output member; the insertion slots are respectively communicated with the positive stiffness mechanism installation cavity and the negative stiffness mechanism installation cavity.

[0014] In some embodiments, the chip attitude adaptive bonding mechanism with precise force control further includes a mounting base, the output end of the rapid feed driving device is connected to the mounting base, and the fine motion device and the first output member are arranged on the mounting base.

[0015] In some embodiments, the chip attitude adaptive bonding mechanism with precise force control further includes a flexible guiding mechanism, one end of the flexible guiding mechanism is connected to the first output member, the other end of the flexible guiding mechanism is fixed on the mounting base, and the flexible guiding mechanism is used to guide the first output member to move in the first direction.

[0016] In some embodiments, the fine motion device is a piezoelectric ceramic actuator.

[0017] In some embodiments, a ball hinge for connecting a bonding head is arranged at the output end of the second output member; the constant force mechanism, the fine motion device and the dynamic strain measurement component are all multiple and are arranged in one-to-one correspondence.

[0018] An embodiment of the second aspect of the present invention provides a chip attitude adaptive bonding method with precise force control, which is applied to the chip attitude adaptive bonding mechanism with precise force control according to the embodiment of the first aspect of the present invention, and includes the following steps:

[0019] S1: The rapid feed driving device drives the constant force mechanism;

[0020] S2: Obtain the relative displacement value;

[0021] S3: When the relative displacement value is within the preset relative displacement range, turn off the rapid feed driving device and turn on the fine motion device.

[0022] An embodiment of the third aspect of the present invention provides a chip attitude adaptive bonding system with precise force control, including a vibration isolation table, a heating and constant temperature table, a gantry, the chip attitude adaptive bonding mechanism with precise force control according to the embodiment of the first aspect of the present invention and a bonding head; the heating and constant temperature table is arranged on the vibration isolation table, and the heating and constant temperature table is used for placing a substrate and heating the substrate; the gantry is movably arranged on the vibration isolation table; the chip attitude adaptive bonding mechanism with precise force control is movably arranged on the gantry; the bonding head is connected to the second output member of the chip attitude adaptive bonding mechanism with precise force control, and the bonding head is used for adsorbing a chip.

[0023] As can be seen from the technical solution, the embodiments provided by the present invention have the following advantages: (1) Before bonding, the fast feed driving device drives the constant force mechanism to move, driving the whole constant force mechanism and the chip on the bonding head to quickly approach the substrate; when the bonding is completed, the fast feed driving device drives the constant force mechanism to quickly return, so that the fast feed driving device can shorten the time to improve the production and packaging efficiency; (2) When the chip contacts the substrate, the chip acts on the second output member in the reverse direction, causing the second output member to move relative to the first output member, that is, a relative displacement starts to exist between the second output member and the first output member. When the relative displacement value is within the preset relative displacement range, the fast feed driving device is in the off state and the fine motion device is in the on state, and the output force applied by the second output member to the bonding head is constant, improving the stability of the bonding force and being beneficial to improving the bonding quality; (3) Within the preset relative displacement range, the fine motion device is used for driving, and the fine motion device can provide a small displacement, which is beneficial to improving the control accuracy; (4) Within the preset relative displacement range, the constant force mechanism has a buffering effect within the preset relative displacement range, which is beneficial to improving the force overshoot caused by turning off the fast feed device; (5) Since the bonding force of the constant force mechanism is constant within the preset relative displacement range, compared with the related art, the present application only involves simple displacement feedback control, that is, only the relative displacement value between the second output member and the first output member in the constant force mechanism needs to be concerned and the relative displacement value is made to be within the preset relative displacement value range, without involving the complex trajectory planning of the linear motor for acceleration and deceleration, thus simplifying the control process of chip bonding and improving the efficiency of chip bonding and packaging. 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 for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0025] Figure 1 is a schematic diagram of the overall structure of a bonding system according to an embodiment of the present invention;

[0026] Figure 2 is a simplified schematic diagram of the overall structure of a bonding system according to an embodiment of the present invention;

[0027] Figure 3 is a force-displacement relationship diagram of a chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention, where the thickened part of the line is a curve with a slope of zero;

[0028] Figure 4It is a structural diagram of the chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention during the bonding process. Among them, the first constant force mechanism, the second constant force mechanism, and the third constant force mechanism all undergo relative displacements;

[0029] Figure 5 It is according to Figure 4 The force-displacement relationship diagram drawn;

[0030] Figure 6 It is a structural diagram of the chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention during the bonding process. Among them, the first constant force mechanism, the second constant force mechanism, and the third constant force mechanism all undergo relative displacements, and the relative displacement values of the three are all within a preset relative displacement range;

[0031] Figure 7 It is according to Figure 6 The force-displacement relationship diagram drawn;

[0032] Figure 8 It is a structural diagram of the chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention during the bonding process. Among them, the first constant force mechanism, the second constant force mechanism, and the third constant force mechanism all undergo relative displacements and the relative displacement values of the three are all within a preset relative displacement range. At this time, the rapid feed driving device stops driving, and the fine motion device continues to drive to keep the bonding;

[0033] Figure 9 It is according to Figure 8 The force-displacement relationship diagram drawn;

[0034] Figure 10 It is a structural diagram of the chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention during the bonding process. Among them, after the bonding is completed, the rapid feed driving device drives the constant force mechanism back to the initial position;

[0035] Figure 11 It is according to Figure 10 The force-displacement relationship diagram drawn;

[0036] Figure 12 It is a structural schematic diagram of the chip attitude adaptive bonding mechanism with precise force control according to an embodiment of the present invention;

[0037] Figure 13 It is a structural schematic diagram of the constant force mechanism according to an embodiment of the present invention;

[0038] Figure 14 It is a structural schematic diagram of the mounting seat according to an embodiment of the present invention;

[0039] Figures 15 - 22It is a schematic diagram of the bonding process of a chip attitude adaptive bonding mechanism with precise force control and its corresponding force-displacement relationship diagram when the chip and the substrate are not parallel;

[0040] Figures 23 - 24 In the related art, it is a schematic diagram of false soldering caused by the non-parallelism between the substrate and the chip;

[0041] Figures 25 - 26 In the related art, it is a schematic diagram of false soldering caused by inconsistent solder ball sizes.

[0042] Reference numerals:

[0043] Chip attitude adaptive bonding system 1000 with precise force control;

[0044] Chip attitude adaptive bonding mechanism 100 with precise force control, vibration isolation table 200, heating and constant temperature table 300, gantry 400, bonding head 500, guide rail 600;

[0045] Constant force mechanism 1, first constant force mechanism 101, second constant force mechanism 102, third constant force mechanism 103, first output member 11, insertion groove 111, positive stiffness mechanism installation cavity 112, negative stiffness mechanism installation cavity 113, second output member 12, positive stiffness mechanism 13, negative stiffness mechanism 14;

[0046] Fast feed driving device 2, actuator 21;

[0047] Micro-motion device 3, first micro-motion device 301, second micro-motion device 302, third micro-motion device 303;

[0048] Dynamic strain measurement component 4, first dynamic strain measurement component 401, second dynamic strain measurement component 402, third dynamic strain measurement component 403;

[0049] Control device 5;

[0050] Mounting seat 6, fixing part 61, micro-motion device mounting groove 62;

[0051] Flexible guiding mechanism 7;

[0052] Ball hinge 8;

[0053] Chip 91, solder ball 92, copper substrate 93, base 94. Detailed implementation manners

[0054] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0055] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0056] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "mounted", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] The present invention belongs to the field of semiconductor packaging, including multiple fields such as CPU, GPU, and high-speed DRAM chip packaging, 3D packaging, system-level packaging, photon component packaging, and Micro / MiniLED mass transfer.

[0058] With the rapid development of electronic products towards miniaturization, flexibility, and 3D integration, the characteristics of high-density, thin and light chips are becoming more and more prominent. However, the existing semiconductor manufacturing methods that improve the integration degree by reducing the feature size are gradually approaching the physical limit. Therefore, advanced electronic packaging technologies represented by chip bonding packaging are becoming an effective method to solve this thorny problem.

[0059] During the chip bonding process, high-reliability chip interconnection must be ensured to improve the yield of chip products. However, low-precision bonding force control will reduce the reliability of chip interconnection.

[0060] Piezoelectric ceramic actuator: Abbreviated as PZT, the full English name is piezoelectric ceramics.

[0061] Therefore, the present invention proposes a chip attitude adaptive bonding mechanism 100, method, and system 1000 with precise force control.

[0062] Refer to the following Figures 1 - 22 to describe the chip attitude adaptive bonding mechanism 100 with precise force control according to an embodiment of the present invention.

[0063] Embodiment 1

[0064] As Figure 1 、 Figure 2 and Figure 12 shown, this embodiment provides a chip attitude adaptive bonding mechanism 100 with precise force control. The chip attitude adaptive bonding mechanism 100 with precise force control includes a constant force mechanism 1, a rapid feed driving device 2, and a fine motion device 3.

[0065] As Figure 12 described, the constant force mechanism 1 includes a first output member 11, a second output member 12, a positive stiffness mechanism 13, and a negative stiffness mechanism 14. The second output member 12 is movably arranged on the first output member 11, and the second output member 12 is connected to the bonding head 500.

[0066] As Figure 12 shown, the positive stiffness mechanism 13 is installed between the first output member 11 and the second output member 12, and the negative stiffness mechanism 14 is installed between the first output member 11 and the second output member 12. The positive stiffness mechanism 13 and the negative stiffness mechanism 14 are arranged in parallel so that the output force of the second output member 12 is constant within a preset relative displacement range.

[0067] Combined with Figure 23 , the rapid feed driving device 2 can drive the constant force mechanism 1 to move in the first direction, and the fine motion device 3 can drive the first output member 11 to move in the first direction.

[0068] It should be emphasized that the output displacement of the fine motion device 3 is in the range of micrometers to millimeters.

[0069] When the relative displacement value of the second output member 12 is within the preset relative displacement range, the control device 5 controls the rapid feed driving device 2 to close and controls the fine motion device 3 to open.

[0070] Please refer to Figure 3 , Figure 3The thick line segment in [Figure] is used to identify the curve with a slope of zero. Within the preset relative displacement range, the output force of the second output member 12 is constant, and its working principle is as follows: The positive stiffness mechanism 13 has a stiffness of K1 in the working direction of the second output member 12, and the negative stiffness mechanism 14 has a stiffness of K2 in the working direction of the second output member 12. The parallel connection of the positive stiffness mechanism 13 and the negative stiffness mechanism 14 means that the stiffnesses of the two are added together. That is to say, within the preset relative displacement range, K1 and K2 are opposite numbers to each other, and the stiffness of the positive stiffness mechanism 13 cancels out the stiffness of the negative stiffness mechanism 14, that is, K1 + K2 = 0. Therefore, within the preset relative displacement range, the second output member 12 will have a situation where the displacement increases but the output force remains unchanged.

[0071] It should be further noted that the preset relative displacement range can be understood from the following several dimensions: (1) The relative displacement in the preset relative displacement range refers to the relative displacement between the second output member 12 and the first output member 11; (2) The preset relative displacement range is determined based on the output force - displacement characteristic curve of the second output member 12, that is, the displacement interval corresponding to the zero slope (see the thick line segment in [Figure]) in this curve. Within this displacement interval, the displacement of the second output member 12 changes, but the magnitude of the output force of the second output member 12 is constant; (3) The determination of the preset relative displacement range is obtained through experimental tests. Figure 3 the thick line segment in [Figure]), within which the displacement of the second output member 12 changes, but the magnitude of the output force of the second output member 12 is constant; (3) The determination of the preset relative displacement range is obtained through experimental tests.

[0072] The micro - motion device 3 here has a displacement resolution of more than sub - micron level and a motion speed of millimeter per second. Within the preset relative displacement range, the micro - motion device 3 outputs displacement to the first output member 11, and the micro - motion device 3 controls the relative displacement of the second output member 12 relative to the second output member 12, which is beneficial to improving the control accuracy during the bonding process.

[0073] In the related art, it is necessary to perform position control on the linear motor to move the solder ball to near the substrate at a very high speed; during the bonding process, control the linear motor to perform force / position switching. At this time, the linear motor switches from high speed to low speed and outputs a stable bonding force, and at the same time, the bonding force is monitored and feedback - controlled in real time. It can be seen that during the bonding process, not only the position of the linear motor needs to be fed back, but also the bonding force applied by the linear motor needs to be fed back. In this application, since the bonding force of the constant - force mechanism 1 within the preset relative displacement range is constant, only the relative displacement between the second output member 12 and the first output member 11 needs to be concerned. Through simple displacement feedback control, the stability of the bonding force is improved, which is beneficial to maintaining the constancy of the bonding force during the bonding process, thereby ensuring the stability of the bonding force.

[0074] For the convenience of description below, Figures 2 - 11 the first constant - force mechanism 101 in [Figure] is used for illustration, and the corresponding relative displacement values of the first constant - force mechanism 101 are A1, A2, and A3 respectively.

[0075] As can be seen from the technical solution, the embodiments provided by the present invention have the following advantages:

[0076] (1) Please refer to Figure 2 and Figure 3 . Before bonding, the rapid feed driving device 2 drives the constant force mechanism 1 to move, driving the whole constant force mechanism 1 and the chip on the bonding head 500 to quickly approach the substrate; please refer to Figure 10 and Figure 11 . When the bonding is completed, the rapid feed driving device 2 drives the constant force mechanism 1 to quickly return. Thus, the rapid feed driving device 2 can shorten the time to improve the production and packaging efficiency;

[0077] (2) Please refer to Figure 4 and Figure 5 . After the chip contacts the substrate, the chip acts on the second output member 12 in the reverse direction, causing the second output member 12 to move relative to the first output member 11, that is, a relative displacement begins to exist between the second output member 12 and the first output member 11; please refer to Figure 6 and Figure 7 . When the relative displacement value is within the preset relative displacement range, the rapid feed driving device 2 is in the off state, the fine motion device 3 is in the on state, and the output force applied by the second output member 12 to the bonding head 500 is constant; please refer to Figure 8 and Figure 9 . The second output member 12 continuously outputs displacement, keeping the chip 91 and the copper substrate 93 bonded under the condition of constant bonding force, improving the stability of the bonding force and being beneficial to improving the bonding quality;

[0078] (3) Within the preset relative displacement range, driving by the fine motion device 3 is beneficial to improving the control accuracy;

[0079] (4) Within the preset relative displacement range, the constant force mechanism 1 has a buffering effect within the preset relative displacement range, which is beneficial to improving the force overshoot caused by turning off the rapid feed device;

[0080] (5) Please refer to Figure 3 . Since the bonding force of the constant force mechanism 1 is constant within the preset relative displacement range, compared with the related technology, the present application only involves simple displacement feedback control, that is, only the relative displacement value between the second output member 12 and the first output member 11 in the constant force mechanism 1 needs to be concerned and the relative displacement value is made to be within the preset relative displacement value range, without involving the complex trajectory planning of the linear motor acceleration and deceleration, thus simplifying the control process of chip bonding and improving the efficiency of chip bonding and packaging.

[0081] Embodiment Two

[0082] This embodiment is basically the same as Embodiment 1, except that: This embodiment provides a method for measuring the relative displacement between the first output member 11 and the second output member 12.

[0083] As Figure 2 and Figure 12 shown, further, the chip attitude adaptive bonding mechanism 100 with precise force control further includes a dynamic strain measurement component 4 and a control device 5. The dynamic strain measurement component 4 can obtain the strain signals of the positive stiffness mechanism 13 and / or the negative stiffness mechanism 14, that is, the dynamic strain measurement component 4 can obtain the strain signal of the positive stiffness mechanism 13, or the dynamic strain measurement component 4 can obtain the strain signal of the negative stiffness mechanism 14, or the dynamic strain measurement component 4 can obtain the strain signals of the positive stiffness mechanism 13 and the negative stiffness mechanism 14. The control device 5 is electrically connected to the fast feed driving device 2, the control component is electrically connected to the fine motion device, and the control device 5 is also electrically connected to the dynamic strain measurement component 4. The control device 5 can convert the strain signal into the displacement value of the second output member 12, the control device 5 can also control the operating state of the fast feed driving device 2, and the control device 5 can also control the operating state of the fine motion device 3.

[0084] As Figure 12 shown, in this embodiment, the relative displacement between the first output member 11 and the second output member 12 causes the positive stiffness mechanism 13 and the negative stiffness mechanism 14 to deform. The dynamic strain measurement component 4 obtains the strain signal of the positive stiffness mechanism 13 and transmits it to the control device 5. The control device 5 converts the strain signal into a displacement value. The relationship between the strain value of the positive stiffness mechanism 13 and the displacement value of the second output member 12 is uniquely determined after experimental measurement. Therefore, the control device 5 can inversely deduce the relative displacement value corresponding to a certain determined strain value according to the displacement-strain relationship.

[0085] It can be understood that the dynamic strain measurement component 4 obtains the strain signal of the negative stiffness mechanism 14 and transmits it to the control device 5. The control device 5 converts the strain signal into a displacement value. The relationship between the strain value of the negative stiffness mechanism 14 and the displacement value of the second output member 12 is uniquely determined after experimental measurement. Therefore, the control device 5 can inversely deduce the relative displacement value corresponding to a certain determined strain value according to the displacement-strain image.

[0086] Further, the control device 5 further includes a comparison module. The comparison module can compare the relative displacement value with a preset relative displacement range; the preset relative displacement range has a minimum endpoint value (the left endpoint corresponding to the thick line segment in the F-x relationship image). As Figure 5 shown, when the relative displacement value is between zero and the minimum endpoint value, the fine motion device 3 is opened; as Figure 7As shown, when the relative displacement value is the minimum end point value, the rapid feed driving device 2 is closed. That is to say, after the chip 91 contacts the substrate, the chip 91 reacts on the second output member 12. There is a tendency for relative displacement between the second output member 12 and the first output member 11. The dynamic strain measuring device detects the strain signal, and the relative displacement value may be zero. At the same time, the control device 5 turns on the fine motion device 3. The relative displacement of the second output member 12 is the sum of the displacements of the fine motion device 3 and the rapid feed driving device 2. When the relative displacement is the minimum end point value, the control device 5 closes the rapid feed driving device 2. At this time, the rapid feed driving device 2 inevitably has a force overshoot phenomenon. The constant force mechanism 1 has a constant bonding force within the preset relative displacement range. Within the preset relative displacement range, the constant force mechanism 1 has a buffering effect within the preset relative displacement range, which is beneficial to further improving the influence of the force overshoot caused by closing the rapid feed device.

[0087] Embodiment III

[0088] This embodiment is basically the same as Embodiment II, and specifically defines the specific components of the dynamic strain measurement assembly 4.

[0089] As Figure 12 shown, further, the dynamic strain measurement assembly 4 includes a strain gauge. The strain gauge can be disposed on the positive stiffness mechanism 13, or the strain gauge can be disposed on the negative stiffness mechanism 14.

[0090] Optionally, the dynamic strain measurement assembly 4 can adopt an optical strain sensor.

[0091] As Figure 12 shown, further, the positive stiffness mechanism 13 is configured as a positive stiffness beam structure, and the negative stiffness beam is configured as a negative stiffness beam structure. The negative stiffness beam here can adopt an inclined beam structure.

[0092] Embodiment IV

[0093] This embodiment is basically the same as Embodiment I, and specifically defines the structure of the first output member 11.

[0094] As Figure 12 and Figure 13 shown, further, the first output member 11 is provided with an insertion slot 111. The insertion slot 111 extends along the first direction. The second output member 12 is disposed in the insertion slot 111, and the second output member 12 can move along the first direction in the insertion slot 111.

[0095] As Figure 13 shown, further, the first output member 11 is further provided with a positive stiffness mechanism installation cavity 112 and a negative stiffness mechanism installation cavity 113. The insertion slot 111 is respectively communicated with the positive stiffness mechanism installation cavity 112 and the negative stiffness mechanism installation cavity 113.

[0096] As Figure 13 shown, in combination with the above embodiments, the positive stiffness mechanism 13 may adopt a positive stiffness beam structure, and the positive stiffness beam structure is disposed in the positive stiffness mechanism installation cavity 112 of the first output member 11. One end of the positive stiffness beam structure is fixed to the second output member 12, and the other end is fixed to the first output member 11.

[0097] As Figure 13 shown, the negative stiffness mechanism 14 may adopt a negative stiffness beam structure, and the negative stiffness beam structure is disposed in the negative stiffness mechanism installation cavity 113 of the first output member 11. One end of the negative stiffness beam structure is fixed to the second output member 12, and the other end is fixed to the first output member 11.

[0098] In a specific example, the negative stiffness beam structure and the positive stiffness beam structure are symmetrically arranged on both sides of the first output member 11.

[0099] Embodiment Five

[0100] This embodiment is basically the same as Embodiment One, and specifically defines the installation positions of the rapid feed device and the fine motion device 3.

[0101] As Figure 14 shown, further, the chip attitude adaptive bonding mechanism 100 with precise force control further includes a mounting base 6. The output end of the rapid feed driving device 2 is connected to the mounting base 6, and the fine motion device 3 and the first output member 11 are disposed on the mounting base 6. The fine motion device 3 is fixed on the mounting base 6, and the output end of the fine motion device 3 is connected to the first output member 11 and drives the first output member 11 to move relative to the mounting base 6.

[0102] Combined with Figures 12 - 14 shown, further, the chip attitude adaptive bonding mechanism 100 with precise force control further includes a flexible guiding mechanism 7. One end of the flexible guiding mechanism 7 is connected to the first output member 11, and the other end of the flexible guiding mechanism 7 is fixed to the mounting base 6. The flexible guiding mechanism 7 is used to guide the first output member 11 to move in the first direction. The flexible guiding mechanism 7 is used for linear motion guiding in the first direction, so as to cause the first output member 11 to generate a linear displacement.

[0103] Optionally, the flexible guiding mechanism 7 realizes linear motion guiding in the first direction through a plurality of distributed flexible branched chains symmetrically arranged with respect to the first direction.

[0104] Combined with Figures 12 - 14 shown, specifically, a fine motion device installation groove 62 is formed on the mounting base 6. The fine motion device 3 is fixed in the fine motion device installation groove 62 through a fastener. The flexible branched chains are four, and each flexible branched chain is integrally arranged on the mounting base 6. A fixing portion 61 is further provided on the mounting base 6, and the end of the flexible branched chain away from the mounting base 6 is fixedly connected to the fixing portion 61 of the mounting base 6.

[0105] Optionally, the flexible guiding mechanism 7 can also be driven by a voice coil motor.

[0106] Embodiment Six

[0107] This embodiment is basically the same as Embodiment One, and specifically defines that the fine motion device 3 is a piezoelectric ceramic actuator.

[0108] Embodiment Seven

[0109] As Figure 12 shown, this embodiment is basically the same as Embodiment Two, the difference being that: a ball hinge 8 is provided at the output end of the second output member 12, the second output member 12 is connected to the bonding head 500 through the ball hinge 8, and the constant force mechanism 1, the fine motion device 3, and the dynamic strain measurement component 4 are all multiple and are arranged in one-to-one correspondence.

[0110] In the related art, the warping of the chip causes phenomena such as non-parallelism between the solder balls and the substrate, which leads to false soldering of the chip. Taking the ball grid array package in chip bonding and packaging as an example, due to problems faced in the actual production process such as different sizes of solder balls and non-parallelism between the chip and the substrate, the phenomenon of false soldering of the chip, also known as HIP (Head-in-Pillow), reduces the yield of chip packaging.

[0111] As Figure 23 shown, a chip 91a is adsorbed on the bonding head 500a, solder balls 92a are connected to the chip 91a, the chip 91a and the substrate 94a are not parallel, and at the same time, it is not parallel to the copper substrate 93a connected to the substrate 94a. At this time, the false soldering phenomenon as shown in Figure 24 may occur.

[0112] As Figure 25 shown, a chip 91b is adsorbed on the bonding head 500b, solder balls 92b are connected to the chip 91b, the chip 91b and the substrate 94b are not parallel, and at the same time, it is not parallel to the copper substrate 93b connected to the substrate 94b. At this time, the false soldering phenomenon as shown in Figure 26 may occur.

[0113] By providing a ball hinge 8 at the output end of the second output member 12 in this application, the bonding head 500 can perform yaw rotation, changing from a single-degree-of-freedom bonding head to a multi-degree-of-freedom bonding head, enabling the chip to adaptively fit the substrate and providing a more solid foundation for realizing reliable bonding between the chip and the substrate.

[0114] The chip attitude adaptive bonding mechanism 100 with precise force control in this embodiment has more degrees of freedom, enabling the chip 91 to adaptively fit the substrate, thereby solving the problem of virtual soldering caused by non-parallelism between the solder balls 92 and the substrate during the bonding and packaging process of the chip 91, and greatly improving the high reliability of chip 91 interconnection.

[0115] As Figure 2 and Figure 12 shown, in combination with the above embodiments, there are multiple constant force mechanisms 1, multiple micro motion devices 3, and multiple dynamic strain measurement components 4, which are arranged in one-to-one correspondence. The multiple constant force mechanisms 1 are arranged on the mounting base 6, the multiple micro motion devices 3 are arranged on the mounting base 6, and each dynamic strain measurement component 4 is used to measure the strain signals of the corresponding positive stiffness mechanism 13 and / or negative stiffness mechanism 14 obtained.

[0116] First, obtain the relationship between the displacements and strains of the three constant force mechanisms.

[0117] Secondly, as Figures 2 - 11 shown, during the chip 91 bonding process, the rapid feed driving device 2 (i.e., the linear motor) drives the mounting base 6 and the three chip attitude adaptive bonding mechanisms 100 with precise force control on the mounting base 6 to move downward; when the chip 91 is initially in contact with the substrate, the strain gauges pasted on each constant force mechanism 1 generate corresponding strain signals, and the control device 5 converts the corresponding strain signals into displacement feedback signals (i.e., relative displacement values), and the control device 5 generates a driving signal to control the opening of the micro motion device 3. The displacements of the micro motion device 3 and the rapid feed driving device 2 are superimposed, so that each constant force mechanism 1 enters the corresponding preset relative displacement range, and the constant force mechanism 1 directly outputs a constant force to achieve high-precision bonding force control; then the linear motor stops moving and maintains the bonding. Due to the constant force characteristic of the multi-degree-of-freedom constant force mechanism 1 (the output force remains unchanged while the displacement increases within its preset relative displacement range), no force overshoot phenomenon will occur during this process; finally, when the bonding is completed, the linear motor quickly returns to the initial position, and a chip bonding and packaging process is completed. The core is the buffering effect of the chip attitude adaptive bonding mechanism 100 with precise force control within the preset relative displacement range. It can achieve rapid bonding under simple displacement feedback control, and maintain the constancy of the bonding force and eliminate the bonding force overshoot phenomenon during the bonding process, thereby ensuring the stability of the bonding force.

[0118] As Figure 2 shown, in a specific example, the first constant force mechanism 101, the second constant force mechanism 102, and the third constant force mechanism 103 are all centrally symmetrically arranged on the mounting base 6; the first micro motion device 301, the second micro motion device 302, and the third micro motion device 303 are all fixed on the mounting base 6.

[0119] Please continue to refer to Figure 2 , the first micro motion device 301, the first dynamic strain measurement component 401, and the first constant force mechanism 103 are correspondingly arranged, and the relative displacement values corresponding to the strain signals of the first dynamic strain measurement component 401 are A1, A2, A3 (as Figure 5 , Figure 7 and Figure 9as shown); the second micro-motion device 302, the second dynamic strain measurement component 402, and the second constant force mechanism 102 are correspondingly arranged, and the relative displacement values corresponding to the strain signals of the second dynamic strain measurement component 402 are B1, B2, B3 (as Figure 5 , Figure 7 and Figure 9 shown); the third micro-motion device 303, the third dynamic strain measurement component 403, and the third constant force mechanism 103 are correspondingly arranged, and the relative displacement values corresponding to the strain signals of the third dynamic strain measurement component 403 are C1, C2, C3 (as Figure 5 , Figure 7 and Figure 9 shown).

[0120] Please continue to refer to Figure 2 . The control device 5 compares the relative displacement values A1, A2, A3 with the preset relative displacement range of the first constant force mechanism 101; similarly, the control device 5 compares the relative displacement values B1, B2, B3 with the preset relative displacement range of the second constant force mechanism 102; similarly, the control device 5 compares the relative displacement values C1, C2, C3 with the preset relative displacement range of the third constant force mechanism 103.

[0121] Although the relative displacement values are different, the forces output by the first constant force mechanism 101, the second constant force mechanism 102, and the third constant force mechanism 103 are constant forces.

[0122] In addition, it should be further noted that the chip attitude self-adaptive process of the chip attitude self-adaptive bonding mechanism 100 with precise force control is as follows: as Figure 12 shown, the output ends of the second output members 12 of the three constant force mechanisms 1 are connected to three positions on the bonding head 500. The relative displacement value of the first constant force mechanism 101 is A, the relative displacement value of the second constant force mechanism 102 is B, and the relative displacement value of the third constant force mechanism 103 is C. Taking the non-parallelism between the chip 91 and the substrate 94 as an example, during the process of the solder ball on the chip 91 being bonded to the copper substrate 93 of the substrate 94, the following four steps can be carried out: (1) as Figures 15 - 16 shown, the bonding head 500 drives the chip 91 to approach the substrate 94. The chip 91 and the substrate 94 are not parallel, and at this time, none of the three constant force mechanisms 1 generates relative displacement; (2) as Figures 17 - 18 shown, when the bonding head 500 bonds downward, the solder ball 92 at the first constant force mechanism 101 first contacts the copper substrate 93, and the first constant force mechanism 101 first enters the preset relative displacement range, while the solder balls 92 at the second and third constant force mechanisms have not yet contacted the substrate, and the spherical pair rotates to adjust the positional relationship between the chip 91 and the substrate 94; (3) as Figures 19 - 20As shown, when the bonding head 500 continues to move downward for bonding, the solder balls 92 at the second and third constant-force mechanisms also come into contact with the substrate successively. After the second constant-force mechanism 102 enters the preset relative displacement range, the third constant-force bonding mechanism 103 has not yet entered the preset relative displacement range, while the first and second constant-force mechanisms continue to move within the preset relative displacement range; (4) As Figures 21 - 22 shown, different deformations are generated by the first constant-force mechanism 101, the second constant-force mechanism 102, and the third constant-force mechanism 103, enabling the bonding head 500 and the chip 91 thereon to adapt to the inclined substrate 94, ensuring the reliability of chip interconnection.

[0123] Embodiment Eight

[0124] This embodiment provides a chip attitude adaptive bonding method with precise force control, which can be applied to the above-mentioned chip attitude adaptive bonding mechanism 100 with precise force control, and includes the following steps:

[0125] S1: The rapid feed driving device 2 drives the constant-force mechanism 1.

[0126] S2: Obtain the relative displacement value.

[0127] S3: When the relative displacement value is within the preset relative displacement range, turn off the rapid feed driving device 2 and turn on the fine motion device 3 to maintain bonding.

[0128] S4: When the bonding is completed, the rapid feed driving device 2 quickly returns to the initial position, and a chip bonding and packaging process is completed.

[0129] In the method provided in this embodiment, since the bonding force of the constant-force mechanism 1 is constant within the preset relative displacement range, only the relative displacement between the second output member 12 and the first output member 11 in the constant-force mechanism 1 needs to be concerned. Through simple displacement feedback control, the stability of the bonding force is improved, which is beneficial to maintaining a constant bonding force during the bonding process, thereby ensuring the stability of the bonding force. At the same time, when the relative displacement value is within the preset relative displacement range, the rapid feed driving device 2 is in the off state and the fine motion device 3 is in the on state, and the output force applied by the second output member 12 to the bonding head 500 is constant, which is beneficial to improving the bonding quality.

[0130] Compared with the related technology, the bonding method only involves simple displacement feedback control, that is, only the relative displacement value between the second output member 12 and the first output member 11 in the constant-force mechanism 1 needs to be concerned and the relative displacement value is always within the preset relative displacement value range, without involving the complex trajectory planning of the linear motor for acceleration and deceleration, thereby simplifying the control process of chip 91 bonding and improving the efficiency of chip 91 bonding and packaging.

[0131] Embodiment Nine

[0132] As shown Figure 1 in FIG. 1, this embodiment provides a chip attitude adaptive bonding system 1000 with precise force control. The bonding system 1000 includes a vibration isolation table 200, a heating and constant temperature table 300, a bonding head 500, a gantry 400, and the chip attitude adaptive bonding mechanism 100 with precise force control in any of the above embodiments.

[0133] The heating and constant temperature table 300 is arranged on the vibration isolation table 200. The heating and constant temperature table 300 is used to place the substrate and heat the substrate. The gantry 400 is movably arranged on the vibration isolation table 200, and the gantry 400 can approach or move away from the heating and constant temperature table 300. The chip attitude adaptive bonding mechanism 100 with precise force control is movably arranged on the gantry 400. The bonding head 500 is connected to the second output member 12 of the chip attitude adaptive bonding mechanism 100 with precise force control, and the bonding head 500 is used to adsorb the chip 91.

[0134] In a specific example, a ball hinge is provided between the bonding head 500 and the second output member 12.

[0135] The vibration isolation table 200 here is a marble vibration isolation table 200, which is used to reduce the influence of external vibration on the bonding and packaging accuracy of the chip 91 in the whole system.

[0136] This system is mainly used in semiconductor packaging applications such as chip 91 bonding and packaging. Due to its high density, high performance, and high reliability, chip 91 bonding and packaging are widely used in many fields such as communication, computer, consumer electronics, and automotive electronics. Especially in the occasions where high-density connection and high-speed data transmission are required, chip 91 bonding and packaging have become the preferred packaging form.

[0137] When the chip 91 and the substrate 94 need to be packaged, the substrate 94 is placed on the heating and constant temperature table 300, the bonding head 500 adsorbs the chip 91, and the gantry 400 drives the chip attitude adaptive bonding mechanism 100 with precise force control to approach the heating and constant temperature table 300, so that the chip 91 and the substrate 94 are opposite to each other in the first direction.

[0138] Start the chip attitude adaptive bonding mechanism 100 with precise force control. The bonding head 500 drives the chip 91 to move, and the solder balls 92 on the chip 91 gradually approach the copper substrate 93. After the solder balls 92 contact the copper substrate 93, the heating and constant temperature table 300 enters the molten state to complete the chip 91 bonding and packaging process, heat the temperature to the target temperature, and keep this temperature all the time.

[0139] In some examples, a guide rail 600 for guiding the movement of the gantry is provided between the gantry 400 and the vibration isolation table 200.

[0140] The rapid feed driving device 2 (not shown in the figure) is fixed on the gantry 400. The rapid feed device 2 drives the chip attitude adaptive bonding mechanism 100 with precise force control to move through the actuator 21.

[0141] Other components and operations of the bonding system 1000 according to the embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail here. In the description of the present invention, "the first feature" and "the second feature" may include one or more of such features. Among them, the up-down direction, left-right direction, and front-back direction are based on the up-down direction, left-right direction, and front-back direction shown in the figure.

[0142] In the description of the present invention, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature.

[0143] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0144] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A chip attitude adaptive bonding mechanism with precise force control, characterized in that Comprising: A constant force mechanism (1), the constant force mechanism (1) includes a positive stiffness mechanism (13), a negative stiffness mechanism (14), a first output member (11) and a second output member (12), the second output member (12) is movably arranged on the first output member (11) and is used to connect the bonding head (500), and the second output member (12) has a relative displacement value in a first direction relative to the first output member (11); The positive stiffness mechanism (13) and the negative stiffness mechanism (14) are installed in parallel between the first output member (11) and the second output member (12) so that the output force of the second output member (12) is constant within a preset relative displacement range; A rapid feed driving device (2), the rapid feed driving device (2) is used to drive the constant force mechanism (1) to move in the first direction, and the rapid feed driving device (2) is configured to be turned off when the relative displacement value of the second output member (12) is within the preset relative displacement range; A fine motion device (3), used to drive the first output member (11) to move in the first direction, and the fine motion device (3) is configured to be turned on when the relative displacement value of the second output member (12) is within the preset relative displacement range.

2. The chip attitude adaptive bonding mechanism with precise force control according to claim 1, characterized in that, It further includes a dynamic strain measurement component (4) and a control device (5); The dynamic strain measurement component (4) is used to obtain the strain signals of the positive stiffness mechanism (13) and / or the negative stiffness mechanism (14); The control device (5) is electrically connected to the rapid feed driving device (2), the fine motion device (3) and the dynamic strain measurement component (4) respectively, and the control device (5) is used to convert the strain signal into the relative displacement value of the second output member (12); The control device (5) is further used to control the operating states of the rapid feed driving device (2) and the fine motion device (3).

3. The chip attitude adaptive bonding mechanism with precise force control according to claim 2, characterized in that, The control device (5) further includes a comparison module; The comparison module is used to compare the relative displacement value with the preset relative displacement range; The preset relative displacement range has a minimum endpoint value; When the relative displacement value is between zero and the minimum endpoint value, the fine motion device (3) is turned on; When the relative displacement value is the minimum endpoint value, the rapid feed driving device (2) is turned off.

4. The chip attitude adaptive bonding mechanism with precise force control according to claim 2, characterized in that, The dynamic strain measurement component (4) includes strain gauges arranged on the positive stiffness mechanism and / or the negative stiffness mechanism (14).

5. The chip attitude adaptive bonding mechanism with precise force control according to claim 4, characterized in that, The positive stiffness mechanism (13) is constructed as a positive stiffness beam structure, and the negative stiffness beam is constructed as a negative stiffness beam structure.

6. The chip attitude adaptive bonding mechanism with precise force control according to claim 1, characterized in that, An insertion slot (111) extending in the first direction is formed on the first output member (11), and the second output member (12) is arranged in the insertion slot (111).

7. The chip attitude adaptive bonding mechanism with precise force control according to claim 6, characterized in that, A positive stiffness mechanism installation cavity (112) and a negative stiffness mechanism installation cavity (113) are further formed on the first output member (11); The insertion slot (111) is respectively communicated with the positive stiffness mechanism installation cavity (112) and the negative stiffness mechanism installation cavity (113).

8. The chip attitude adaptive bonding mechanism with precise force control according to claim 1, characterized in that, It further includes a mounting base (6), the output end of the quick feed driving device (2) is connected to the mounting base (6), and the fine motion device (3) and the first output member (11) are arranged on the mounting base (6).

9. The chip attitude adaptive bonding mechanism with precise force control according to claim 8, characterized in that, It further includes a flexible guiding mechanism (7), one end of the flexible guiding mechanism (7) is connected to the first output member (11), the other end of the flexible guiding mechanism (7) is fixed on the mounting base (6), and the flexible guiding mechanism (7) is used to guide the first output member (11) to move in the first direction.

10. The chip attitude adaptive bonding mechanism with precise force control according to claim 1, characterized in that, The fine motion device (3) is a piezoelectric ceramic actuator.

11. The chip attitude adaptive bonding mechanism with precise force control according to claim 2, characterized in that, The output end of the second output member (12) is provided with a ball hinge (8) for connecting a bonding head (500); The constant force mechanism (1), the fine motion device (3), and the dynamic strain measurement component (4) are all multiple and are arranged in one-to-one correspondence.

12. A chip attitude adaptive bonding method with precise force control, characterized in that, Applied to the chip attitude adaptive bonding mechanism with precise force control according to any one of claims 1-11, it includes the following steps: S1: The quick feed driving device (2) drives the constant force mechanism (1); S2: Obtain the relative displacement value; S3: When the relative displacement value is within the preset relative displacement range, turn off the quick feed driving device (2) and turn on the fine motion device (3).

13. A chip attitude adaptive bonding system with precise force control, characterized in that It includes: A vibration isolation table (200); A heating and constant temperature table (300), arranged on the vibration isolation table (200), and the heating and constant temperature table (300) is used to place a substrate and heat the substrate; A gantry (400), the gantry (400) is movably arranged on the vibration isolation table (200); According to the chip attitude adaptive bonding mechanism (100) with precise force control according to any one of claims 1-11, it is movably arranged on the gantry (400); A bonding head (500), connected to the second output member (12) of the chip attitude adaptive bonding mechanism (100) with precise force control, and the bonding head (500) is used to adsorb a chip (91).

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