Crystal bonding device and control method thereof

Abstract

The present application discloses a die bonding device and a control method thereof, which relates to the field of chip mounting technology, and can provide a die bonding device with a simple structure and capable of detecting die bonding pressure in real time. The die bonding device includes a housing, a die bonding needle, an elastic connector, a displacement sensor, and a processor. The housing encloses a mounting cavity having a first opening. Part of the die bonding needle is located in the mounting cavity, and part of it extends out of the mounting cavity, and can move relative to the housing to change the length of the portion of the die bonding needle located in the mounting cavity. The elastic connector is located in the mounting cavity, and is configured to provide an elastic force to the die bonding needle to cause the die bonding needle to extend out of the mounting cavity; the elastic force is positively correlated with the length of the die bonding needle located in the mounting cavity. The displacement sensor is located in the mounting cavity, and is configured to detect the displacement of the die bonding needle relative to the housing. The processor is electrically connected to the displacement sensor and the housing, and is configured to control the movement of the housing according to the displacement of the die bonding needle. The present application is used in a die bonding process.

Description

Technical Field

[0001] The present disclosure relates to the technical field of chip mounting, and in particular to a die bonding device and a control method thereof. Background Art

[0002] The die bonding device is a key equipment in the display panel manufacturing production line. Its function is to press and fix the wafer (such as IC chip or LED chip) transferred to the substrate (such as LED panel, PCB board, Mini-LED light board or Micro-LED light board, etc.) on the substrate. Among them, the die bonding process refers to the process of pressing and fixing the wafer on the substrate. Before the wafer is bonded, it is necessary to measure the distance between the die bonding head (the part of the die bonding device used to press the wafer) and the substrate, and then accurately control the downward pressure distance from the die bonding head to the substrate during the die bonding process to prevent light or excessive pressure, resulting in loose wafer bonding or wafer damage; the die bonding process directly affects the packaging effect of the wafer.

[0003] In the prior art, the die bonding device usually uses a laser rangefinder, a visual imaging system or a contact position sensor (such as a tool setting instrument) to measure the distance between the die bonding head and the substrate. However, the above-mentioned distance measuring devices all have different disadvantages. For example, the laser rangefinder is expensive, has a bloated structure, is greatly affected by air disturbance, air temperature and air temperature, has low detection accuracy for transparent glass substrates, requires multiple laser heads for auxiliary testing, and is difficult to maintain and debug; the visual imaging system is expensive, is sensitive to system thermal effects, and has poor height measurement accuracy; the contact position sensor has a limited mechanical life and is not suitable for high-intensity working environments. Summary of the invention

[0004] The embodiment of the present invention provides a die bonding device and a control method thereof, which are used to provide a die bonding device with a simple structure and capable of detecting the die bonding pressure (the pressure applied by the die bonding device on the wafer) in real time.

[0005] To achieve the above objectives, the embodiments of the present disclosure adopt the following technical solutions:

[0006] On the one hand, an embodiment of the present disclosure provides a die-bonding device. The die-bonding device includes a housing, a die-bonding needle, an elastic connector, a displacement sensor, and a processor. The housing encloses an installation cavity having a first opening. Part of the die-bonding needle is located in the installation cavity, and part of the die-bonding needle extends out of the installation cavity through the first opening. And the die-bonding needle can move along a first direction relative to the housing to change the length of the portion of the die-bonding needle located in the installation cavity. The elastic connector is located in the installation cavity and is connected to the housing and the die-bonding needle. The elastic connector is configured to provide an elastic force to the die-bonding needle to cause the die-bonding needle to extend out of the installation cavity. The above elastic force is positively correlated with the length of the die-bonding needle located in the installation cavity. The displacement sensor is located in the installation cavity and is configured to detect the displacement of the die-bonding needle relative to the housing. The processor is electrically connected to the displacement sensor and the housing, and is configured to control the movement of the housing along the first direction according to the displacement of the die-bonding needle relative to the housing.

[0007] The crystal bonding device provided by the embodiment of the present disclosure moves along the first direction and in the direction close to the wafer until the crystal bonding needle contacts the wafer, and the processor controls the housing to continue to move in the direction close to the wafer, the crystal bonding pressure between the crystal bonding needle and the wafer increases, and pushes the crystal bonding needle to move in the first direction away from the wafer compared to the housing, that is, the crystal bonding needle shrinks into the installation cavity. The elastic force applied by the elastic connector to the crystal bonding needle is positively correlated with the length of the crystal bonding needle in the installation cavity, that is, it is positively correlated with the displacement of the crystal bonding needle shrinking into the installation cavity compared to the housing. In this way, in the process of the crystal bonding needle shrinking into the installation cavity compared to the housing, the elastic force applied by the elastic connector to the crystal bonding needle gradually increases, and the crystal bonding pressure between the crystal bonding needle and the wafer gradually increases. The displacement sensor detects the displacement of the crystal bonding needle compared to the housing until the displacement meets the preset condition, that is, it is considered that the crystal bonding pressure meets the preset condition, and then the housing is controlled by the processor to stop moving in the direction close to the wafer, and moves in the first direction away from the wafer, and then leaves the wafer, completing a crystal bonding process of the wafer. Based on the above-mentioned crystal bonding process, the crystal bonding device provided by the embodiment of the present disclosure can detect the length of the crystal bonding needle in the installation cavity in real time as the crystal bonding process progresses, that is, detect the displacement of the crystal bonding needle relative to the housing in real time, and then detect the crystal bonding pressure applied by the crystal bonding device on the wafer in real time. The detection efficiency and detection measurement accuracy are high, and the adaptability to the environment and substrate is strong. Different environments and substrates do not affect the crystal bonding accuracy of the crystal bonding device. In addition, the crystal bonding device has a simple structure, small size, and light weight, which is conducive to reducing the moving weight of the equipment and increasing the number of crystals to be bonded.

[0008] In some embodiments, the crystal fixing needle includes an extension portion and a first limiting portion, wherein the extension portion extends in a first direction, and is partially located in the mounting cavity, and partially extends out of the mounting cavity through the first opening; the first limiting portion is located in the mounting cavity, connected to the extension portion, and extends in a direction perpendicular to the extension portion. The housing includes a card plate, which is disposed in the mounting cavity and is located on a side of the first limiting portion away from the first opening. The elastic connector includes a spring, which is sleeved on the outside of the extension portion, one end of which is fixedly connected to the first limiting portion, and the other end of which is fixedly connected to the card plate.

[0009] In some embodiments, the spring is always in a compressed state, and one end of the spring abuts against the first limiting portion, and the other end abuts against the clamping plate.

[0010] In some embodiments, the housing further comprises a bottom plate, and the first opening is disposed on the bottom plate, wherein the boundary of the orthographic projection of the first limiting portion on the bottom plate is at least partially located outside the boundary of the first opening.

[0011] In some embodiments, the card plate includes a second opening, and a portion of the extension extends into a side of the card plate away from the first opening through the second opening. The solid crystal needle also includes a measuring target plate, which is located at the end of the portion of the extension located in the mounting cavity and is perpendicular to the first direction. The displacement sensor is disposed on a side of the measuring target plate away from the first opening, and has a first interval between the measuring target plate and the measuring target plate, and is configured to detect the size of the first interval along the first direction.

[0012] In some embodiments, the distance between the bottom plate and the clamping plate is smaller than the distance between the first limiting portion and the measurement target plate.

[0013] In some embodiments, the crystal bonding needle further includes a second limiting portion, the second limiting portion is located outside the mounting cavity, the second limiting portion is connected to the extending portion, and the second limiting portion extends in a direction perpendicular to the extending portion.

[0014] In some embodiments, the interval between the first limiting portion and the second limiting portion is smaller than the maximum interval between the measurement target plate and the displacement sensor.

[0015] In some embodiments, the displacement sensor includes one of an eddy current displacement sensor, a capacitive displacement sensor, and a laser displacement sensor.

[0016] In some embodiments, the housing includes a device support, a syringe, a floating bearing, and a sensor fixture. The device support includes a mounting hole extending along a first direction. The syringe includes a base plate, a card plate, and a side plate. Along the first direction, the base plate and the card plate are arranged opposite to each other, and the base plate is located on a side of the card plate away from the device support. A first opening is provided on the base plate, and a second opening is provided on the card plate at a position opposite to the first opening. The card plate covers the opening of the mounting hole and is fixedly connected to the device support. The side plate is arranged around the base plate and the card plate, and one end is connected to the base plate, and the other end is connected to the card plate. The floating bearing is arranged in the first opening; wherein the solid crystal needle passes through the floating bearing. The sensor fixture is arranged in the mounting cavity, and is configured to fix the displacement sensor to the inner wall of the mounting cavity.

[0017] On the other hand, some embodiments of the present disclosure further provide a control method for a crystal bonding device, which is used to control the crystal bonding device described in any of the above embodiments. The control method includes: the processor controls the housing to drive the crystal bonding needle to synchronously move along the first direction toward the side close to the wafer until the crystal bonding needle abuts against the wafer, and continues to control the housing to move along the first direction toward the side close to the wafer. The displacement sensor detects the displacement of the crystal bonding needle compared to the housing. The processor obtains the displacement, processes and determines whether the displacement is greater than a first threshold. If so, the processor controls the housing to move in the opposite direction; if not, the processor controls the housing to continue to move along the first direction toward the side close to the wafer.

[0018] The control method of the die bonding device provided in the embodiment of the present disclosure has the same functions and beneficial effects as those achieved by the above-mentioned die bonding device, and will not be described in detail here.

[0019] In some embodiments, when the displacement is less than the first threshold value, and before the processor controls the housing to continue to move along the first direction toward the side close to the wafer, the control method further includes: determining whether the displacement reaches a maximum displacement. If so, the processor reports an error and controls the die bonding device to shut down; if not, the processor controls the housing to continue to move along the first direction toward the side close to the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual sizes of the products involved in the embodiments of the present disclosure.

[0021] Figure 1 A schematic diagram of the structure of a die bonding device according to some embodiments of the present disclosure;

[0022] Figure 2 A schematic diagram of the structure of a die-bonding needle according to some embodiments of the present disclosure;

[0023] Figure 3 It is a schematic diagram of the structure when the first limiting part of some embodiments of the present disclosure abuts against the bottom plate;

[0024] Figure 4 It is a schematic diagram of the structure when the second limiting part of some embodiments of the present disclosure abuts against the bottom plate;

[0025] Figure 5 A schematic diagram of the structure of a die-bonding needle according to some embodiments of the present disclosure;

[0026] Figure 6 The present invention is a flow chart of a control method of a die bonding device according to some embodiments of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0028] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as an open, inclusive meaning, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary" or "such as" are intended to indicate that specific features, structures, materials or characteristics related to the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0029] In the description of the present disclosure, it is necessary to understand that the orientations or positional relationships indicated by terms such as "center", "up", "down", "left", "right", "vertical", and "horizontal" are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0030] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0031] In the description of the present disclosure, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0032] The use of "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0033] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within the acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0034] Some embodiments of the present disclosure provide a die bonding device 100. Figure 1 The die-bonding device 100 includes a housing 10 , a die-bonding needle 20 , an elastic connecting member 30 , a displacement sensor 40 and a processor 50 .

[0035] The housing 10 defines a mounting cavity 102 having a first opening 101 .

[0036] The crystal pin 20 is partially located in the mounting cavity 102, and partially extends out of the mounting cavity 102 from the first opening 101. The crystal pin 20 can be moved along the first direction Y ( Figure 1 The die-bonding needle 20 moves in the vertical direction (in the vertical direction) to change the length of the portion of the die-bonding needle 20 located in the mounting cavity 102.

[0037] That is, the crystal bonding needle 20 passes through the first opening 101, and is partially located in the installation cavity 102 and partially located outside the installation cavity 102. In some embodiments below, the portion of the crystal bonding needle 20 located in the installation cavity 102 is referred to as the first portion, and the portion of the crystal bonding needle 20 located outside the installation cavity 102 is referred to as the second portion.

[0038] For example, Figure 2 As shown, in the die bonding process, the substrate 300 is usually placed horizontally below the die bonding device 100 in the vertical direction. This is beneficial to the stability of the chip 200 during the die bonding process and reduces the risk of the chip 200 moving relative to the substrate 300.

[0039] During the crystal bonding process, after the crystal bonding needle 20 abuts against the wafer 200, the crystal bonding needle 20 can move in the first direction Y compared to the housing 10 during the movement of the housing 10 along the first direction Y. For example, in the process of the housing 10 moving downward along the first direction Y (in the direction close to the wafer 200) to further press the wafer 200, the crystal bonding needle 20 can move upward along the first direction Y (away from the wafer 200) compared to the housing 10, and the length of the crystal bonding needle 20 retracted into the installation cavity 102 increases. Conversely, after the crystal bonding is completed, in the process of the housing 10 moving upward along the first direction Y to leave the wafer 200, the crystal bonding needle 20 can move downward along the first direction Y compared to the housing 10, and the length of the crystal bonding needle 20 retracted into the installation cavity 102 decreases. That is, when the crystal bonding needle 20 moves upward along the first direction compared to the housing 10, the length of the first portion of the crystal bonding needle 2 increases. Conversely, when the crystal bonding needle 20 moves downward along the first direction compared to the housing 10, the length of the first portion of the crystal bonding needle 20 decreases.

[0040] The elastic connector 30 is located in the mounting cavity 102 and is connected to the housing 10 and the die-bonding pin 20. The elastic connector 30 is configured to provide an elastic force F to the die-bonding pin 20 so that the die-bonding pin 20 extends out of the mounting cavity 102. That is, the elastic connector 30 is used to provide an elastic force F in a vertical downward direction to the die-bonding pin 20. The elastic force F is positively correlated with the length of the die-bonding pin 20 in the mounting cavity 102, that is, the elastic force F increases as the length of the die-bonding pin 20 in the mounting cavity 102 increases, and decreases as the length of the die-bonding pin 20 in the mounting cavity 102 decreases.

[0041] The elastic connecting member 30 is configured to apply an elastic force F to the crystal bonding needle 20 to make the crystal bonding needle 20 move downward in a first direction (extend out of the mounting cavity 102 ), so that during the crystal bonding process of the crystal bonding needle 20 , the elastic force F can enable the crystal bonding needle 20 to apply a pressure to the wafer 200 .

[0042] During the crystal bonding process, the crystal bonding needle 20 abuts against the chip 200, and the housing 10 continues to move downward along the first direction. The crystal bonding needle 20 can produce an upward movement along the first direction compared to the housing 10. In this way, the length D of the crystal bonding needle 20 contracted into the installation cavity 102 gradually increases, the elastic force F applied by the elastic connecting part 30 to the crystal bonding needle 20 gradually increases, and the pressure applied by the crystal bonding needle 20 to the chip 200 gradually increases.

[0043] Exemplarily, the elastic connector 30 and the housing 10, and the elastic connector 30 and the crystal-bonding needle 20 can be detachably connected to facilitate the installation, removal and later maintenance of the elastic connector 30. For example, the elastic connector 30 and the housing 10 can be connected by a snap, or abutted (the two are in contact with each other and exert force on each other on the contact surface). The elastic connector 30 and the crystal-bonding needle 20 can be connected by a snap, or abutted. The connection method between the elastic connector 30 and the housing 10 can be the same as or different from the connection method between the elastic connector 30 and the crystal-bonding needle 20.

[0044] It should be understood that the elastic connector 30 is not limited to the above-mentioned connection with the housing 10 and the die-bonding pin 20. The above-mentioned connection methods are only some possible implementation methods, not limitations of the present application. For example, the elastic connector 30 and the housing 10 may also be connected in a non-detachable manner, such as by welding. The embodiments of the present disclosure do not impose restrictive requirements on this.

[0045] The displacement sensor 40 is located in the installation cavity 102 and is configured to detect the displacement of the die-bonding pin 20 relative to the housing 10. The processor 50 is electrically connected to the displacement sensor 40 and the housing 10 and is configured to control the housing 10 to move along a first direction according to the displacement of the die-bonding pin 20 relative to the housing 10.

[0046] Exemplarily, the displacement sensor 40 can detect the displacement of the die bonding needle 20 compared to the housing, and transmit the detected displacement to the processor 50. The processor 50 determines whether the displacement meets the displacement required for die bonding, and controls the housing 10 to move upward or downward in a first direction (see the embodiment of the control method of the die bonding device below for details).

[0047] In summary, the crystal bonding device 100 provided in the embodiment of the present disclosure moves in a first direction downward (towards the direction close to the wafer 200) until the crystal bonding needle 20 contacts the wafer 200, and the crystal bonding device 100 continues to move downward in the first direction, the crystal bonding pressure between the crystal bonding needle 20 and the wafer 200 increases, and pushes the crystal bonding needle 20 to move upward in the first direction compared to the housing 10, that is, the crystal bonding needle 20 shrinks into the installation cavity 102. The elastic force applied by the elastic connector 30 to the crystal bonding needle 20 is positively correlated with the displacement of the crystal bonding needle 20 shrinking into the installation cavity 102 compared to the housing 10. In this way, in the process of the crystal bonding needle 20 shrinking into the installation cavity 102 compared to the housing 10, the elastic force F applied by the elastic connector 30 to the crystal bonding needle 20 gradually increases, and the force of the crystal bonding device 100 pressing the wafer 200 gradually increases. The displacement sensor 40 detects the displacement of the bonding needle 20 compared to the housing 10 until the displacement meets the preset conditions, that is, it is considered that the bonding pressure meets the preset conditions. The processor 50 controls the housing 10 to stop moving in the direction approaching the chip, and move along the first direction Y in the direction away from the chip 200, and then leave the chip 200, completing a bonding process of the chip 200.

[0048] Based on the above-mentioned solid crystal process, the solid crystal device 100 provided by the embodiment of the present disclosure can detect the length of the solid crystal needle 20 in the installation cavity 102 in real time during the solid crystal process, that is, detect the displacement of the solid crystal needle 20 compared to the housing 10 in real time, and then detect the solid crystal pressure applied by the solid crystal device 100 on the wafer 200 in real time. The detection efficiency and detection measurement accuracy are high, and the adaptability to the environment and substrate is strong. Different environments and substrates do not affect the solid crystal accuracy of the solid crystal device. In addition, the solid crystal device has a simple structure, small size, and light weight, which is conducive to reducing the moving weight of the equipment and increasing the number of solid crystals.

[0049] In some embodiments, Figure 1 As shown, the housing 10 may include a device support 11, a syringe 12, a floating bearing 13 and a sensor fixing member 14. The device support 11, the syringe 12 and the floating bearing 13 together form a mounting cavity 102. The sensor fixing member 14 is disposed in the mounting cavity 102 and is used to fix the displacement sensor 40 to the side wall of the mounting cavity 102.

[0050] The device support 11 includes a mounting hole extending along the first direction Y. Exemplarily, the device support 11 may be a partial structure of a mechanical arm (used to drive the housing 10 to move) or a suction cup (eg, used to absorb, transfer and place the wafer 200) in a die bonder.

[0051] Along the first direction Y, the syringe 12 is disposed at one end of the device support 11 close to the wafer 200 during the crystal bonding process; illustratively, Figure 2As shown, along the first direction Y, the lower end of the device support 11 is close to the wafer 200 during the crystal bonding process, and the syringe 12 is arranged below the device support 11.

[0052] Exemplarily, the syringe 12 is detachably fixedly connected to the device support 11, so as to facilitate the disassembly, replacement and subsequent maintenance of the syringe 12 and the parts disposed in the installation cavity 102. For example, the syringe 12 and the device support 11 can be connected by screws or by a snap-fit ​​structure, which is not specifically limited in the embodiments of the present disclosure.

[0053] In some embodiments, see Figure 1 and Figure 3 The syringe 12 may include a bottom plate 121, a clamping plate 122 and a side plate 123. Along the first direction Y, the bottom plate 121 is arranged opposite to the clamping plate 122, and the bottom plate 121 is located on the side of the clamping plate 122 away from the device bracket 11. The bottom plate 121 is provided with a first opening 101, and the clamping plate 122 is provided with a second opening 103 at a position opposite to the first opening 101. The clamping plate 122 covers the opening of the mounting hole 131 and is fixedly connected to the device bracket 11; the side plate 123 is arranged around the bottom plate 121 and the clamping plate 122, and one end is connected to the bottom plate 121, and the other end is connected to the clamping plate 122.

[0054] The floating bearing 13 is disposed at the first opening 101 and is fixedly attached to the side wall of the first opening 101. The floating bearing 13 can reduce the sliding friction between the die-bonding pin 20 and the housing 10, improve the sensitivity of the die-bonding pin 20 moving along the first direction Y, and improve the die-bonding accuracy of the die-bonding device 100.

[0055] It is understandable that the floating bearing 13 may also be other components that can reduce the friction between the crystal bonding needle 20 and the housing. For example, the floating bearing 13 may also be an axial sliding bearing, a disc spring structure or an air bearing.

[0056] The sensor fixing member 14 is disposed in the installation cavity 102 and is configured to fix the displacement sensor 40 to the inner wall of the installation cavity 102 .

[0057] Exemplarily, the sensor fixing member 14 can be an annular structure, whose outer wall is fixedly connected to the inner wall of the mounting cavity 102 (for example, by screw connection, threaded connection, interference fit, snap connection, bonding or welding, etc.), and the inner wall is fixedly connected to the displacement sensor 40 (for example, by bonding, screw connection, snap connection, etc.).

[0058] In some embodiments, see Figure 3 and Figure 5The die-bonding needle 20 includes an extending portion 21 and a first limiting portion 22 . The extending portion 21 extends along the first direction Y, and is partially located in the mounting cavity 102 , and partially extends out of the mounting cavity 102 through the first opening 101 .

[0059] The first limiting portion 22 is located in the installation cavity 102, connected to the extension portion 21, and extends in a direction perpendicular to the extension portion 21. Exemplarily, the first limiting portion 22 can be arranged on at least one side of the extension portion 21, for example, the first limiting portion 22 can include a protrusion formed along the radial direction of the extension portion 21 and protruding toward a side away from the extension portion 21; or, the first limiting portion 22 includes a plurality of first sub-limiting portions (for example, two, three, four or more), each of which protrudes along the radial direction of the extension portion 21 and protrudes toward a side away from the extension portion 21, and the plurality of first sub-limiting portions are evenly arranged along the circumference of the extension portion 21; or, the first limiting portion 22 is an annular structure surrounding the extension portion 21. The embodiments of the present disclosure do not specifically limit this.

[0060] When the housing 10 includes the clamping plate 122 , the clamping plate 122 is disposed in the installation cavity 102 and is located at a side of the first limiting portion 22 away from the first opening 101 .

[0061] The elastic connecting member 30 includes a spring 31 . The spring 31 is sleeved on the outer side of the extending portion 21 , one end of the spring 31 is fixedly connected to the first limiting portion 22 , and the other end of the spring 31 is fixedly connected to the clamping plate 122 .

[0062] In some embodiments, the spring 31 is always in a compressed state, so that the spring 31 can apply a pre-tightening force to the die-bonding needle 20 , that is, before the die-bonding needle 20 contacts the wafer 200 , the spring 31 applies an initial elastic force to the die-bonding needle 20 .

[0063] One end of the spring 31 abuts against the first limit portion 22, and the other end abuts against the clamping plate 122. The spring 31 can be pressed against the first limit portion 22 and the clamping plate 122 under the action of the initial elastic force F0. The spring 31 abuts against the first limit portion 22 and the clamping plate 122, and the connection is reliable, and no additional connector is required. The structure is simple, which is conducive to reducing the installation difficulty and manufacturing cost of the die-bonding device 100.

[0064] It is understandable that the initial elastic force applied by the spring 31 to the crystal bonding needle 20 is less than the crystal bonding pressure required for the wafer to be bonded, so that the crystal bonding device 100 can be prevented from directly crushing the wafer. The spring 31 can also be always in a stretched state, so that the two ends of the spring 31 are fixedly connected to the clamping plate 122 and the first limit portion 22 through an additional connection structure.

[0065] In some embodiments, the boundary of the orthographic projection of the first limit portion 22 on the bottom plate 121 is at least partially located outside the boundary of the first opening 101. In this way, when the die-bonding pin 20 moves downward along the first direction relative to the housing 10, the first limit portion 22 can abut against the bottom plate 121, thereby preventing the die-bonding pin 20 from completely sliding out of the installation cavity 102 through the first opening 101.

[0066] In which, when the housing 10 includes a floating bearing 13 arranged in the first opening 101, the boundary of the positive projection of the first limiting portion 22 on the bottom plate 121 is at least partially located outside the boundary of the first opening 101, and the pressure of the first limiting portion 22 on the floating bearing 13 can also be reduced, thereby improving the stability of the floating bearing 13.

[0067] In some embodiments, see Figure 3 The card plate 122 includes a second opening 103 , and a portion of the extension portion 21 extends from the second opening 103 into a side of the card plate 122 away from the first opening 101 .

[0068] The solid crystal needle 20 further includes a measurement target plate 23, which is located at the end of the portion (first portion) of the extension portion 21 located in the installation cavity, that is, the measurement target plate 23 is arranged at the upper end of the first portion; and the measurement target plate 23 is perpendicular to the first direction Y.

[0069] The displacement sensor 40 is disposed on a side of the measurement target plate 23 away from the first opening 101 and has a first interval with the measurement target plate 23. The displacement sensor 40 is configured to detect a size of the first interval along the first direction Y. The displacement sensor 40 can detect the displacement of the die-bonding needle 20 along the first direction by detecting a change in the first interval.

[0070] Exemplarily, the orthographic projection of the displacement sensor 40 on the measurement target plate 23 is located inside the measurement target plate 23 , so that the influence of other structures on the die bonding device 100 on the measurement and detection results can be reduced, and the measurement accuracy of the displacement sensor 40 can be improved.

[0071] In some embodiments, Figure 3 As shown, the interval between the bottom plate 121 and the clamping plate 122 is smaller than the interval between the first limit portion 22 and the measuring target plate 23. In this way, when the solid crystal needle 20 moves downward along the first direction until the first limit portion 22 abuts against the bottom plate 121, there is a gap between the measuring target plate 23 and the clamping plate 122, thereby preventing the measuring target plate 23 from colliding with the clamping plate 122, thereby preventing the measuring target plate 23 from deforming, and improving the detection accuracy of the displacement sensor 40.

[0072] In some embodiments, see Figure 3 and Figure 4The crystal-bonding needle 20 also includes a second limit portion 24, which is located outside the installation cavity 102, connected to the extension portion 21, and extends in a direction perpendicular to the extension portion 21. The boundary of the orthographic projection of the second limit portion 24 on the bottom plate 121 is at least partially located outside the boundary of the first opening 101. In this way, during the crystal bonding process, the crystal-bonding needle 20 moves upward along the first direction, and the second limit portion 24 abuts against the bottom plate 121 to prevent the crystal-bonding needle 20 from completely shrinking into the installation cavity 102. The crystal-bonding device 100 can effectively press the wafer 200 through the crystal-bonding needle 20 to fix the wafer 200 on the substrate 300.

[0073] It should be understood that it can be set that when the second limit portion 24 abuts against the base plate 121, the elastic force applied by the elastic connecting member 30 to the crystal bonding needle 20 is greater than the maximum crystal bonding pressure required for the chip 200 during the crystal bonding process. In this way, the crystal bonding needle 20 can complete the crystal bonding before the second limit portion 24 abuts against the base plate 121, so that the crystal bonding pressure applied by the crystal bonding needle 20 on the chip 200 increases linearly.

[0074] In some embodiments, see Figure 4 , the interval between the first limiter 22 and the second limiter 24 is smaller than the maximum interval between the measuring target plate 23 and the displacement sensor 40. When the first limiter 22 abuts against the bottom plate 121, the interval between the measuring target plate 23 and the displacement sensor 40 reaches the maximum. In this way, the collision between the measuring target plate 23 and the displacement sensor 40 during the die bonding process can be avoided, the risk of damage to the displacement sensor 40 is reduced, and the reliability of the die bonding device 100 is improved.

[0075] In some embodiments, the displacement sensor 40 includes one of an eddy current displacement sensor, a capacitive displacement sensor, and a laser displacement sensor. Of course, the displacement sensor 40 can also be a 2-wire type, a 3-wire type, a 4-wire type, or other types. The above-mentioned types of sensors have higher measurement accuracy and higher measurement efficiency, which is conducive to improving the bonding reliability and bonding efficiency of the die bonding device 100.

[0076] It is understandable that the displacement sensor 40 may also be other types of sensors, such as a proximity sensor. The embodiments of the present disclosure are not listed one by one.

[0077] Exemplarily, the displacement sensor 40 may include a sensor pin 41, and the sensor pin 41 may be divided into a positive pin and a negative pin. The physical quantity detected by the displacement sensor 40 may be a voltage change or a current change.

[0078] For example, the displacement sensor 40 may sense the displacement of the target plate 23 as a current change, a voltage change, or other digital signals.

[0079] The processor 50 may include a signal converter 51 and a controller 52. The signal converter 51 is electrically connected to the sensor pin 41 through a signal line, and is configured to convert the voltage change or current change detected by the displacement sensor 40 into a digital signal or other signal. The controller 52 is electrically connected to the signal converter 51 through a wiring harness, and is configured to receive the signal converted by the signal converter 51, and judge whether the die bonding pressure meets the die bonding requirement through the signal, and then control the housing to move upward or downward in the first direction.

[0080] Exemplarily, the displacement sensor 40 and the signal converter 51 may be connected via a coaxial cable, a shielded cable, a soft or hard PCB board, or other connection structures, so as to achieve signal transmission between the two.

[0081] According to the crystal bonding device 100 provided in the above embodiment, the sensor 40 and the crystal bonding needle 20 are integrated in the design, the contact wafer 200 of the crystal bonding needle 20, and the measurement target plate 23 thereof move synchronously, and the sensor 40 is located in the installation cavity (closed environment) to implement the measurement of the displacement of the crystal bonding needle 20, which can provide real-time feedback on the height of the substrate 300 and the displacement of the crystal bonding needle 20 compared to the housing 10, which is beneficial to improving the measurement accuracy and efficiency. At the same time, the crystal bonding device has a simple structure, a small volume, and a reduced moving weight of the device, which is beneficial to improving the crystal bonding efficiency of the device. Moreover, it has better adaptability to different substrates (such as transparent substrates) and different application environments (environmental temperature and humidity, etc.), strong anti-interference ability, and low cost. Chips at different height positions on the substrate can be effectively bonded, and the height difference of different areas of the substrate 300 can be compensated.

[0082] Some embodiments of the present disclosure also provide a control method for a die-bonding device, which is used to control the die-bonding device 100 in any of the above embodiments. Figure 2 and Figure 6 , the control method includes S100~S700.

[0083] S100 , the processor 50 controls the housing 10 to move along the first direction Y toward the side close to the wafer (downward) until the die bonding needle 20 abuts against the wafer 200 and moves relative to the housing 10 along the first direction toward the side away from the wafer.

[0084] Exemplarily, after the die-bonding needle 20 contacts the wafer 200, the wafer 200 is pushed downward by the initial elastic force. When the wafer 200 contacts the substrate 300, the wafer 200 stops moving downward, and the die-bonding needle 20 stops moving. The initial elastic force applied by the spring 31 to the die-bonding needle 20 is less than the die-bonding pressure required for the wafer 200 to be bonded. Therefore, the housing 10 continues to move downward in the first direction, and the housing 10 and the die-bonding needle 20 generate relative movement. The spring 31 is compressed, and the elastic force applied by the spring 31 to the die-bonding needle 20 increases, and the die-bonding pressure applied by the die-bonding needle 20 to the wafer 200 gradually increases.

[0085] S200 , the displacement sensor 40 detects the displacement of the die-bonding pin 20 along the first direction Y relative to the housing 10 .

[0086] Exemplarily, after the housing 10 and the die-bonding needle 20 generate relative movement, the interval between the displacement sensor 40 and the measurement target plate 23 changes, and the displacement sensor 40 detects the above interval change, which is the displacement L of the die-bonding needle 20 relative to the housing 10 along the first direction Y.

[0087] The elastic force F applied by the spring 31 to the die-bonding pin 20 = the initial elastic force F0 applied by the spring to the die-bonding pin 20 + ML, where M is the elastic coefficient of the spring 31 and L is the relative displacement between the die-bonding pin 20 and the housing 10 .

[0088] Exemplarily, when the housing 10 and the die-bonding needle 20 produce relative movement, the current I or voltage U inside the displacement sensor 40 changes accordingly, and ΔI=KL, or ΔU=KL; wherein K is the transfer function between the displacement of the die-bonding needle 20 in the displacement sensor 40 and the current change ΔI or the voltage change ΔU, which can be determined experimentally.

[0089] S300, the processor 50 obtains the size of the displacement L, and determines whether the displacement L is greater than or equal to a first threshold L1.

[0090] It is understandable that the displacement L obtained by the processor 50 may be a physical quantity directly measured by the displacement sensor 40 and related to the displacement L; for example, it may be a current change ΔI or a voltage change ΔU inside the displacement sensor 40 .

[0091] Exemplarily, the displacement sensor 40 transmits the measured current change ΔI or voltage change ΔU to the signal converter 51 of the processor 50, which is then processed by the signal converter 51 (such as encoding, filtering, etc.) and sent to the controller 52. The controller 52 determines whether the obtained current change ΔI or voltage change ΔU meets the die bonding requirements.

[0092] S500: If yes, the processor 50 controls the housing 10 to move in the reverse direction.

[0093] Exemplarily, the current variation ΔI is greater than the minimum current variation ΔI required for die bonding. min , that is, the elastic force F is greater than the minimum bonding pressure required for bonding. This proves that the wafer 200 is firmly connected to the substrate 300. Therefore, the processor 50 controls the housing 10 to move in the reverse direction (upward along the first direction Y), and the elastic force applied by the bonding needle 20 on the wafer 200 gradually decreases until the bonding needle 20 is separated from the wafer 200. This completes a bonding process.

[0094] S600 , if not, the processor 50 controls the housing 10 to continue to move along the first direction Y toward the side close to the wafer 200 (downward).

[0095] Exemplarily, the current variation ΔI is less than the minimum current variation ΔI required for die bonding. min , that is, the elastic force F is less than the minimum bonding pressure required for bonding. This proves that the chip 200 is not yet firmly connected to the substrate 300. Therefore, the processor 50 controls the housing 10 to continue to move downward in the first direction, gradually increasing the elastic force applied by the bonding needle 20 on the chip 200.

[0096] In some embodiments, when the displacement is less than the first threshold, before the processor controls the housing to continue to move along the first direction toward the side close to the wafer, the control method further includes:

[0097] Exemplarily, the displacement being less than the first threshold value may be represented by the current change ΔI measured by the displacement sensor being less than the minimum current change ΔI min , or the voltage change ΔU is less than the minimum current change ΔU min .

[0098] S310, determining whether the displacement L reaches the maximum displacement Lmax.

[0099] Exemplarily, the maximum displacement Lmax refers to the maximum displacement that the die-bonding pin 20 can produce compared to the housing 10 , that is, the interval between the first limiting portion 22 and the second limiting portion 24 .

[0100] S700: If yes, the processor 50 reports an error and controls the die bonding device 100 to shut down.

[0101] After the displacement L reaches the maximum displacement that the die-bonding needle 20 can produce, the elastic force applied by the die-bonding needle 20 on the wafer 200 cannot be accurately detected, which may cause the die-bonding device to crush the wafer 200 and the substrate 300. Therefore, the interval between the first limit portion 22 and the second limit portion 24 can be greater than the minimum displacement requirement of the die-bonding needle 20 for the die-bonding.

[0102] S600 , if not, the processor 50 controls the housing 10 to continue moving along the first direction Y toward the side close to the wafer 200 .

[0103] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0104] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A die bonding device, characterized in that: include: A housing, which encloses a mounting cavity having a first opening, wherein the housing comprises a card plate, and the card plate is disposed in the mounting cavity; A crystal-fixing needle, comprising an extension portion and a first limiting portion, wherein the extension portion extends along a first direction, and is partially located in the installation cavity, and partially extends out of the installation cavity through the first opening; the first limiting portion is located in the installation cavity and is located on a side of the clamping plate close to the first opening, and the first limiting portion is connected to the extension portion and extends in a direction perpendicular to the extension portion; the crystal-fixing needle can move along the first direction relative to the housing to adjust the length of the portion of the crystal-fixing needle located in the installation cavity; An elastic connector is located in the installation cavity, the elastic connector includes a spring, the spring is sleeved on the outside of the extension portion, one end of the spring is fixedly connected to the first limiting portion, and the other end is fixedly connected to the clamping plate, and is configured to provide an elastic force to the crystal-bonding needle to make the crystal-bonding needle extend out of the installation cavity; wherein the elastic force is positively correlated with the length of the crystal-bonding needle in the installation cavity; a displacement sensor, located in the mounting cavity, configured to detect the displacement of the die-bonding pin relative to the housing; The processor is electrically connected to the displacement sensor and the housing, and is configured to control the housing to move along the first direction according to the displacement of the die-bonding pin compared to the housing.

2. The die bonding device according to claim 1, characterized in that: The spring is always in a compressed state; one end of the spring abuts against the first limiting portion, and the other end abuts against the clamping plate.

3. The die bonding device according to claim 2, characterized in that: The housing further comprises a bottom plate, and the first opening is arranged on the bottom plate; wherein, The boundary of the orthographic projection of the first limiting portion on the bottom plate is at least partially located outside the boundary of the first opening.

4. The die bonding device according to claim 3, characterized in that: The card plate comprises a second opening, and a portion of the extension portion extends into a side of the card plate away from the first opening through the second opening; The die-bonding needle further includes a measurement target plate, which is located at the end of the portion of the extension portion located in the installation cavity and is perpendicular to the first direction; The displacement sensor is disposed on a side of the measurement target plate away from the first opening, with a first interval between the measurement target plate and the measurement target plate, and is configured to detect a size change of the first interval along a first direction.

5. The die bonding device according to claim 4, characterized in that: The interval between the bottom plate and the clamping plate is smaller than the interval between the first limiting portion and the measurement target plate.

6. The die bonding device according to claim 4, characterized in that: The solid crystal needle also includes a second limiting portion, which is located outside the mounting cavity, connected to the extension portion, and extends in a direction perpendicular to the extension portion; the boundary of the positive projection of the second limiting portion on the base plate is at least partially located outside the boundary of the first opening.

7. The die bonding device according to claim 6, characterized in that: The interval between the first limiting portion and the second limiting portion is smaller than the maximum interval between the measuring target plate and the displacement sensor.

8. The die bonding device according to any one of claims 1 to 7, characterized in that: The displacement sensor includes one of an eddy current displacement sensor, a capacitive displacement sensor and a laser displacement sensor.

9. The die bonding device according to any one of claims 1 to 7, characterized in that: The housing comprises: An equipment bracket including a mounting hole extending along a first direction; The syringe comprises a bottom plate, a card plate and a side plate; along a first direction, the bottom plate is arranged opposite to the card plate, and the bottom plate is located on a side of the card plate away from the device bracket, the bottom plate is provided with the first opening, and the card plate is provided with a second opening at a position opposite to the first opening, the card plate covers the opening of the mounting hole, and is fixedly connected to the device bracket; the side plate is arranged around the bottom plate and the card plate, and one end is connected to the bottom plate, and the other end is connected to the card plate; A floating bearing is disposed in the first opening; wherein the crystal fixing needle passes through the floating bearing; The sensor fixing member is disposed in the installation cavity and is configured to fix the displacement sensor to the inner wall of the installation cavity.

10. A control method for a die bonding device, used for controlling the die bonding device according to any one of claims 1 to 9, characterized in that: The control method comprises: The processor controls the housing to drive the crystal-bonding needle to move synchronously along the first direction toward the side close to the wafer until the crystal-bonding needle abuts against the wafer, and continues to control the housing to move along the first direction toward the side close to the wafer; The displacement sensor detects the displacement of the die-bonding pin relative to the housing; The processor obtains the displacement, processes and determines whether the displacement is greater than a first threshold; If so, the processor controls the housing to move in the reverse direction; If not, the processor controls the housing to continue moving along the first direction toward the side close to the wafer.

11. The control method according to claim 10, characterized in that: In the case where the displacement is less than the first threshold value, and before the processor controls the housing to continue to move along the first direction toward the side close to the wafer, the control method further includes: The processor determines whether the displacement reaches a maximum displacement; If yes, the processor reports an error and controls the die bonding device to shut down; If not, the processor controls the housing to continue moving along the first direction toward the side close to the wafer.

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