Bonding apparatus, bonding method, and article manufacturing method

Abstract

The invention relates to a bonding apparatus, a bonding method, and an article manufacturing method. A joining apparatus that performs a joining operation of joining a joining object to a joining target object includes: a driving unit configured to perform driving such that the joining object is joined to the joining target object; and a control unit configured to control the joining operation such that a joining shape of the joining object achieves a predetermined twisted shape after the joining object is joined to the joining target object.

Description

Technical Field

[0001] This disclosure relates to joining equipment, joining methods, and methods for manufacturing articles. Background Technology

[0002] Japanese Patent Application Publication No. 2022-169798 discloses a technique in which a bare die (e.g., a chip or semiconductor chip) that is to be bonded to a substrate (bonding target) is bonded to the substrate while the bare die is bent into a downward convex shape.

[0003] In conventional techniques, bonding reliability can be improved by bending the die to the substrate. However, due to the bending of the die, shape errors occur when the die is bonded to a flat substrate, and the bonding accuracy between the die and the substrate is reduced. Summary of the Invention

[0004] This disclosure provides a technique that is advantageous in terms of joint reliability and joint accuracy.

[0005] According to a first aspect of this disclosure, a joining device is provided that performs a joining operation to join a joining object to a joining target object, the joining device comprising: a driving unit configured to drive such that the joining object is joined to the joining target object; and a control unit configured to control the joining operation such that, after the joining object is joined to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape.

[0006] According to a second aspect of this disclosure, a joining method is provided for joining a joining object to a joining target object, the joining method comprising: preparing the joining object and the joining target object; and joining the joining object to the joining target object such that, after joining the joining object to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape.

[0007] According to a third aspect of this disclosure, a joining method is provided, the joining method comprising: joining a first joining object to a joining target object such that, after joining the first joining object to the joining target object, the joining shape of the first joining object achieves a predetermined twisted shape; and joining a second joining object to the first joining object such that, after joining the second joining object to the first joining object on the joining target object, the joining shape of the second joining object achieves the predetermined twisted shape.

[0008] According to a fourth aspect of this disclosure, a bonding method is provided, the bonding method comprising: forming a semiconductor element on a substrate; and bonding a bonding object to the semiconductor element such that, after the bonding object is bonded to the semiconductor element on the substrate, the bonding shape of the bonding object achieves a predetermined twisted shape, wherein, during the formation process, the semiconductor element is formed on the substrate such that the shape of the semiconductor element formed on the substrate achieves the predetermined twisted shape.

[0009] According to a fifth aspect of this disclosure, a bonding method is provided, the bonding method comprising: bonding a first bonding object to a first substrate such that, after the first bonding object is bonded to the first substrate, the bonding shape of the first bonding object achieves a predetermined twisted shape; bonding a second bonding object to a second substrate such that, after the second bonding object is bonded to the second substrate, the bonding shape of the second bonding object achieves the predetermined twisted shape; and bonding the first substrate and the second substrate such that the first bonding object on the first substrate and the second bonding object on the second substrate are bonded together.

[0010] According to a sixth aspect of this disclosure, a method for manufacturing an article is provided, the method comprising: preparing a joining object and a joining target object; joining the joining object to the joining target object using a joining device, the joining device performing a joining operation to join the joining object to the joining target object, the joining device comprising: a driving unit configured to drive such that the joining object is joined to the joining target object; and a control unit configured to control the joining operation such that, after the joining object is joined to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape; and manufacturing an article by processing the joining target object to which the joining object is joined.

[0011] Other aspects of this disclosure will become clear from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0012] Figure 1 This is a schematic view illustrating the arrangement of the joining devices according to one or more aspects of this disclosure;

[0013] Figure 2A and Figure 2B This is a view used to explain the bonding distortion that occurs when the die is bonded to the wafer in the case of a bent die;

[0014] Figure 3 It is used for explanation Figure 1 A flowchart of the joining operation in the joining device shown;

[0015] Figure 4 This is a view showing an example of the sensitivity relating die information, bonding control conditions, and bonding distortion;

[0016] Figure 5 This is a view showing an example of the specific construction of the joint;

[0017] Figures 6A to 6C This is a view showing an example of the specific construction of the joint;

[0018] Figure 7A and Figure 7B This is a view used to explain the joining method according to one or more aspects of this disclosure;

[0019] Figure 8A and Figure 8B This is a view used to explain the joining method according to one or more aspects of this disclosure; and

[0020] Figures 9A to 9C This is a view used to explain the joining method according to one or more aspects of this disclosure. Detailed Implementation

[0021] The embodiments will now be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed disclosure. Multiple features are described in the embodiments, but the disclosure is not limited to requiring all of these features, and multiple features can be appropriately combined. Furthermore, in the drawings, the same or similar constructions are given the same reference numerals, and repeated descriptions thereof are omitted.

[0022] The following description assumes that the bonding object is a separate die including semiconductor elements and the bonding target is a die including semiconductor elements formed on a substrate (wafer), but the bonding object and the bonding target are not limited to this.

[0023] In addition to bare dies containing semiconductor elements formed on a substrate, bonding targets also include, for example, silicon interposers on which wiring is formed, silicon wafers, and glass interposers on which wiring is formed, glass wafers. Bonding targets also include organic interposers on which wiring is formed on organic panels (PCBs), wafers on which semiconductor elements are formed (on which some bare dies containing semiconductor devices have already been bonded), etc.

[0024] Besides separated bare dies, the bonding objects also include, for example, stacks of separated bare dies, small pieces of material, optical components, microelectromechanical systems (MEMS), structures, etc. The bonding methods between the bonding objects and the bonding targets are also unrestricted. Bonding methods include, for example, bonding using adhesives, temporary bonding using temporary adhesives, bonding using hybrid bonding, atomic diffusion bonding, vacuum bonding, bump bonding, etc. Thus, the bonding methods between the bonding objects and the bonding targets include various temporary bonding methods and permanent bonding methods. The bonding steps include various treatments required for each bonding method, such as cleaning, applying adhesives, activating surfaces, applying pressure, heating, etc.

[0025] Industrial application examples of the joining device as an aspect of this disclosure include the following application examples.

[0026] A first application example is the fabrication of stacked memory. When the bonding apparatus, which is an aspect of this disclosure, is applied to the fabrication of stacked memory, the bonding object is a separate memory die, and the bonding target is a memory die formed on a wafer as a semiconductor element. In the fabrication process of stacked memory, approximately eight layers are typically stacked. Therefore, in the bonding of the eighth layer, the bonding target is a substrate that is a wafer to which six layers of memory dies have already been bonded. Note that the last layer may be a driver die used to drive the memory.

[0027] A second application example is heterogeneous integration of processors. Traditional processors are typically System-on-a-Chip (SoC) obtained by forming logic circuitry and static random-access memory (SRAM) within a single semiconductor element. In contrast, in heterogeneous integration, individual components are fabricated on separate wafers, with each component undergoing optimized processing before being bonded together to manufacture the processor. This reduces processor costs and increases throughput. When the bonding apparatus, as an aspect of this disclosure, is applied to heterogeneous integration, the bonding objects are probed and separated dies, such as SRAM, antennas, or drivers. The bonding target is a logic die formed on the wafer as a semiconductor element. Typically, different dies are bonded sequentially. Therefore, the number of bonding objects on the bonding target increases sequentially. For example, in the case where bonding begins with SRAM, when bonding the next die with SRAM, the logic wafer with SRAM bonded to it serves as the bonding target.

[0028] A third application example is 2.5D bonding using a silicon interposer. A silicon interposer is a silicon wafer with wiring formed on it. 2.5D bonding is a method of electrically bonding dies by joining separate dies using a silicon interposer. When the bonding apparatus, as an aspect of this disclosure, is applied to bond dies to a silicon interposer, the bonding objects are separate dies, and the bonding target is the silicon interposer, which is a silicon wafer with wiring formed on it. Typically, multiple types of dies are bonded to the silicon interposer. Therefore, the bonding target also includes the silicon interposer to which several dies are bonded.

[0029] A fourth application example is 2.1D bonding using organic or glass interposers. An organic interposer is an organic panel (PCB substrate or CCL substrate) used as a packaging substrate, on which wiring is formed. A glass interposer is a glass panel with wiring formed. 2.1D bonding is a method of bonding separate dies to an organic or glass interposer to electrically bond the dies via wiring on the interposer. When the bonding apparatus, as an aspect of this disclosure, is applied to bonding dies to an organic interposer, the bonding object is a separate die, and the bonding target is an organic panel with wiring formed. When the bonding apparatus, as an aspect of this disclosure, is applied to bonding dies to a glass interposer, the bonding object is a separate die, and the bonding target is a glass panel with wiring formed. Typically, multiple types of dies are bonded to organic or glass interposers. Therefore, the bonding target also includes an organic or glass interposer to which several dies are bonded.

[0030] The fifth application example is heterogeneous substrate bonding. For example, in the field of infrared image sensors, InGaAs is a well-known high-sensitivity material. Therefore, if InGaAs is used for the sensor unit that receives light and silicon, which enables high-speed processing, is used for the logic circuit that extracts data, a high-sensitivity, high-speed infrared image sensor can be manufactured. However, only substrates (wafers) with diameters as small as 4 inches can be mass-produced from InGaAs crystals, which is smaller than the mainstream 300mm silicon wafer. Therefore, a technique for bonding separate InGaAs substrates to a 300mm silicon wafer with logic circuits has been proposed. The bonding apparatus, as an aspect of this disclosure, can also be applied to heterogeneous substrate bonding for bonding substrates made of different materials and having different sizes. When the bonding apparatus, as an aspect of this disclosure, is applied to heterogeneous substrate bonding, the bonding object is, for example, a small piece of InGaAs material, and the bonding target is, for example, a large-diameter silicon wafer substrate. Note that the small piece of material is a crystal slice. This slice is preferably cut into a rectangle.

[0031] <First Embodiment>

[0032] Figure 1This is a schematic view illustrating the arrangement of the bonding apparatus BD, which is one aspect of this disclosure. The bonding apparatus BD performs a bonding operation to bond a separate die 51 (bonding object) to any position (bonding target portion) on a wafer 6 (bonding target object), which serves as a substrate. The die 51 is provided in a state of being arranged (held) on a cutting tape placed on a cutting frame 5. In this specification, as shown in the figures, directions are represented in the XYZ coordinate system. Generally, the XY plane is a plane parallel to the horizontal plane, and the Z-axis is an axis parallel to the vertical direction. Examples of mutually orthogonal or intersecting directions of the X, Y, and Z axes are shown.

[0033] like Figure 1 As shown, the bonding device BD includes a pickup unit 3 and a bonding unit 4, which are arranged on a base 1 damped by a bracket 2. In this embodiment, the pickup unit 3 and the bonding unit 4 are arranged on a single base 1. However, the pickup unit 3 and the bonding unit 4 can be arranged on separate bases.

[0034] The bonding device BD also includes a control unit CNT, which controls the corresponding units of the bonding device BD. The control unit CNT is formed by, for example, a PLD (an abbreviation for programmable logic device, such as FPGA (an abbreviation for field-programmable gate array)), ASIC (an abbreviation for application-specific integrated circuit)), a general-purpose or special-purpose computer (information processing device) with a program installed, or a combination of all or some of them. The control unit CNT operates the bonding device BD by comprehensively controlling the corresponding units (e.g., pickup unit 3 and bonding unit 4) according to the program stored in the storage unit.

[0035] Pick-up unit 3 includes a pick-up head 31 and a release head 32. Pick-up unit 3 peels the bare die 51 to be bonded to wafer 6 from the dicing tape using the release head 32, and holds the bare die 51 peeled from the dicing tape using the pick-up head 31. Pick-up head 31 rotates the bare die 51, for example, 180°, and delivers it to the bonding head 423 of bonding unit 4.

[0036] The pickup head 31 contacts the bonding surface of the die 51. Therefore, in applications where bonding is performed by activating the surface (e.g., hybrid bonding), it is preferable to treat the surface of the pickup head 31 that contacts the bonding surface. For example, it is preferable to treat the surface as a highly stable surface with a diamond-like carbon (DLC) coating or a fluorine coating, or to reduce the contact area by treating the surface into a high-density small shape (e.g., needle-like). Alternatively, a non-contact holding method such as a Bernoulli chuck or a method that prevents contact with the bonding surface by holding the side surface or edge portion of the die 51 can also be used.

[0037] The bonding unit 4 serves as a bonding device configured to perform a bonding operation to bond the die 51 to the wafer 6. The bonding unit 4 includes a stage base 41 and an upper base 42. A wafer stage 43 is mounted on the stage base 41. The wafer stage 43 is driven by a drive mechanism 436 (e.g., a linear motor) along the X and Y directions. The drive mechanism 436 can also be configured to drive the wafer stage 43 to rotate about an axis parallel to the Z direction. Instead of the drive mechanism 436 driving the wafer stage 43 to rotate about an axis parallel to the Z direction, the bonding head 423 can drive the die 51 to rotate about an axis parallel to the Z direction. The drive mechanism 436 serves as a positioning mechanism that changes the relative position between the wafer chuck 433 (or the wafer 6) and the bonding head 423 (or the die 51).

[0038] A die viewing camera 431 is provided on the wafer stage 43. The die viewing camera 431 acquires images by photographing the die 51 held by the bonding head 423. The control unit CNT detects (designates) the position of characteristic portions of the die 51 held by the bonding head 423 based on the images acquired by the die viewing camera 431. A bar mirror 432 is provided on the wafer stage 43. The bar mirror 432 serves as a target for the interferometer 422.

[0039] In this embodiment, the bonding head 423 serves as a first holding unit for holding the bare die 51. The wafer stage 43 serves as a second holding unit for holding the wafer 6 via the wafer chuck 433.

[0040] In this embodiment, the wafer stage 43 serves as a support structure for the wafer chuck 433 and the die viewing camera 431. The wafer stage 43, serving as the support structure, includes a first end face on the side where the wafer 51 is transferred to the connector 423. Figure 1 The left end face; and the second end face on the opposite side of the first end face (in the middle); Figure 1 (Right end face of the die). The die viewing camera 431 is arranged between the first end face and a virtual plane passing through the center of the wafer stage 43 (support structure) and parallel to the first end face. From another perspective, the die viewing camera 431 is arranged between a predetermined position in the path that transports the die 51 to the bonding head 423 and the wafer chuck 433. The advantage of this configuration is that it reduces the amount of drive required for the wafer stage 43 to observe the die 51 held by the bonding head 423, thereby increasing productivity.

[0041] A wafer observation camera 421 is mounted on the upper base 42. The wafer observation camera 421 acquires images of the wafer 6 held by the wafer chuck 433 (wafer stage 43). The control unit CNT detects (designates) the position of feature portions of the wafer 6 held by the wafer chuck 433 based on the images acquired by the wafer observation camera 421. Based on the position of the feature portions of the wafer 6, the control unit CNT also acquires the positions of multiple bonding target portions on the wafer.

[0042] The upper base 42 is also provided with: an interferometer 422 for measuring the position of the wafer stage 43 using a bar mirror 432; and a bonding head 423 for holding the die 51 passed from the pick-up head 31 and bonding the die to the bonding target position on the wafer 6.

[0043] In this embodiment, the upper base 42 serves as a support structure for the bonding head 423 and the wafer observation camera 421. The upper base 42, serving as the support structure, includes a third end face located on the side where the die 51 is transferred to the bonding head 423. Figure 1 The left end face and the fourth end face located on the opposite side of the third end face. Figure 1 (Right end face of the middle). The wafer observation camera 421 is arranged between the third end face and a virtual plane that passes through the center of the upper base 42 (support structure) and is parallel to the third end face. This configuration helps to reduce the amount of drive required for the wafer stage 43 to observe the wafer 6 held by the wafer chuck 433, thereby increasing production capacity.

[0044] The coupling head 423 is driven along the Z direction by a drive mechanism 425, such as a linear motor. The drive mechanism 425 can also be configured to drive the coupling head 423 in the X and Y directions, or to drive the coupling head 423 to rotate about an axis parallel to the Z direction.

[0045] For example, when bonding the die 51 to a bonding target portion on the wafer 6, the drive mechanism 425 drives the bonding head 423 downward (in the -Z direction), thereby bonding the die 51 held by the bonding head 423 to the bonding target portion on the wafer 6. Alternatively, the drive mechanism 436 may drive the wafer stage 43 upward (in the +Z direction), thereby bonding the die 51 to the bonding target portion on the wafer 6 held by the wafer stage 43 (wafer chuck 433). Note that the drive mechanism (not shown) may drive the wafer chuck 433 upward, thereby bonding the die 51 to the bonding target portion on the wafer 6 held by the wafer chuck 433. Thus, the drive mechanisms 425 and 436 serve as drive units that drive at least one of the bonding head 423 (the die 51 held by the bonding head 423) and the wafer stage 43 (the wafer 6 held by the wafer stage 43) to bond the die 51 to the wafer 6.

[0046] In this embodiment, a pick-up head 31 is used to rotate the die 51 180° and transfer it to the bonding head 423. However, by providing one or more die holding units between the pick-up head 31 and the bonding head 423, the pick-up head 31 can transfer the die 51 to the die holding unit, and the die holding unit can transfer the die 51 to the bonding head 423. Alternatively, a drive mechanism can be provided to drive the bonding head 423, causing the bonding head 423 to receive the die 51 from the pick-up head 31. Note that to improve productivity, the bonding device BD may include multiple pick-up heads, multiple release heads, and multiple bonding heads.

[0047] In this embodiment, when the die 51 is bonded to the wafer 6, to improve bonding reliability, the bonding head 423 bonds the die 51 to the wafer 6, wherein the die 51 is bent into a convex shape toward the wafer 6, that is, the wafer 51 is bent into a downwardly convex shape. More specifically, as Figure 2A As shown, the die 51 is bent into a shape with a protruding central portion and contacts the wafer 6. Therefore, the die 51 gradually bonds to the wafer 6 while pushing air from the central portion to the peripheral portion. However, when the die 51 is bonded to the wafer 6 with the die 51 bent, as... Figure 2B As shown, the shape of the die 51 is distorted, and a shape error (hereinafter referred to as "bonding distortion") occurs in the die 51. The bonding distortion that occurs when bonding the die 51 to the wafer 6 with the die 51 bent causes a deviation in the bonding position of the die 51 relative to the wafer 6, thereby reducing the bonding accuracy between the die 51 and the wafer 6.

[0048] The bonding distortion that occurs when the die 51 is bonded to the wafer 6 is caused by die information about the die 51 and bonding control conditions for the bonding operation. The die information includes, for example, the thickness of the die 51, the dimensions of the die 51, the material of the die 51, and the stress of the semiconductor elements formed on the die 51. The bonding control conditions include, for example, the amount and shape of the bend of the die 51 (central portion relative to peripheral portion), and the relative speed between the die 51 and the wafer 6 when the die 51 is bonded to the wafer 6. The bonding control conditions also include the coefficient of friction of the bonding head 423 holding the die 51 and the holding force of the bonding head 423 holding the die 51.

[0049] Therefore, in this embodiment, the bonding distortion is controlled by adjusting the bonding control conditions related to the bonding operation of bonding the die 51 to the wafer 6 based on the die information. For example, the control unit CNT controls the bonding operation of bonding the die 51 to the wafer 6 such that after the die 51 is bonded to the wafer 6, the bonding shape of the die 51 achieves a predetermined distortion shape.

[0050] refer toFigure 3 The bonding operation (bonding method) in the bonding apparatus BD will be described. As described above, in this embodiment, the bonding operation includes bonding the die 51 to the wafer 6 while the die 51 is bent into a downwardly protruding shape (a protruding shape facing the wafer 6 side). As described above, this bonding operation is performed by the control unit CNT, which comprehensively controls the various units of the bonding apparatus BD. Note that the preparation steps of the die 51 and the wafer 6, as well as the loading steps of loading the prepared die 51 and the wafer 6 into the bonding apparatus BD, have been performed.

[0051] In step S101, the control unit CNT acquires die information related to the die 51 and the target amount of bonding twist of the die 51. As described above, the die information includes at least one of the following: the thickness of the die 51, the size of the die 51, the material of the die 51, and the stress of the semiconductor element formed on the die 51. The target amount of bonding twist of the die 51 includes the target shape of the bonding shape of the die 51 after bonding with the wafer 6, that is, a predetermined twist shape intentionally generated in the die 51. In this way, in this embodiment, the control unit CNT also functions as an acquisition unit that acquires the die information and the target amount of bonding twist (predetermined twist shape). Note that in addition to the die information and the target amount of bonding twist, the control unit CNT can further acquire wafer information related to the wafer 6 and the bonding environment (temperature, humidity, air pressure, equipment status, etc.).

[0052] The target amount of bonding distortion can be specified by, for example, the distortion of each component of the multiplier component, the third-order component, or the higher-order component, or by the distortion of the bonding target portion on wafer 6.

[0053] For example, the control unit CNT obtains the die information and the target amount of bonding twist input by the user via the input unit (user interface) of the bonding equipment BD. However, as die information, the control unit CNT can obtain the thickness and size of the die 51 measured by the die measurement unit of the bonding equipment BD. Similarly, as the target amount of bonding twist, the control unit CNT can obtain the shape (twist amount of the bonding target portion) of the bonding target portion on the wafer 6 measured by the wafer measurement unit of the bonding equipment BD.

[0054] In step S102, based on the die information and target amount of bonding twist obtained in step S101, the control unit CNT calculates the bonding control conditions related to the bonding operation of bonding the die 51 to the wafer 6. As described above, the bonding control conditions include at least one of the following: the amount and shape of bending of the die 51, the relative speed between the die 51 and the wafer 6, the coefficient of friction of the bonding head 423, and the holding force of the bonding head 423.

[0055] The control unit CNT calculates the bonding shape of die 51 after it is bonded to wafer 6 based on the die information, and the bonding control conditions (used as a calculation unit) that ensure the bonding twist occurring in die 51 achieves the target amount (making the bonding shape achieve a predetermined twist shape). The control unit CNT uses optimization methods such as linear programming or machine learning methods to calculate the bonding control conditions that make the bonding twist close to the target amount within the constraints achievable by the bonding device BD. Note that the bonding control conditions that make the bonding twist close to the target amount refer to the bonding control conditions that keep the bonding twist within a predetermined tolerance (margin) range relative to the target amount of the bonding twist.

[0056] Alternatively, such as Figure 4 As shown, the control unit CNT can use the sensitivity representing the relationship between die information, bonding control conditions, and bonding distortion (its magnitude) occurring in die 51 to calculate the bonding control conditions for bonding distortion occurring in die 51 in order to achieve the target amount. Figure 4 The sensitivity is shown to represent the relationship between the thickness of the bare die 51 as bare die information, the amount of bending of the bare die 51 as a bonding control condition, and the magnitude component (amount) of the bonding twist occurring in the bare die 51. Reference Figure 4 As shown in the sensitivity, the control unit CNT calculates the amount of bending of the die 51 corresponding to the target amount of the bonding twist magnification component based on the thickness of the die 51 obtained as die information, as the bonding control condition.

[0057] In step S103, the control unit CNT causes the wafer stage 43 (wafer chuck 433) to hold the wafer 6 loaded in the bonding apparatus BD. The step of the wafer stage 43 holding the wafer 6 includes a bonding preparation step of bonding the die 51 to the wafer 6. The bonding preparation step includes, for example, steps of measuring and positioning alignment marks formed in the wafer 6, and steps of measuring and leveling the surface position of the wafer 6.

[0058] In step S104, the control unit CNT causes the bonding head 423 to hold the die 51 loaded in the bonding apparatus BD. The step of the bonding head 423 holding the die 51 includes a bonding preparation step for bonding the die 51 to the wafer 6. The bonding preparation step includes, for example, steps of measuring and positioning alignment marks formed in the die 51, and steps of measuring and leveling the surface position of the die 51.

[0059] In step S105, the control unit CNT, based on the bonding control conditions calculated in step S102, bonds the die 51 held by the bonding head 423 in step S104 to the wafer 6 (its bonding target portion) held by the wafer stage 43 in step S103 (bonding step). In other words, the control unit CNT controls the bonding operation of bonding the die 51 to the wafer 6, such that after bonding the die 51 to the wafer 6, the bonding shape of the die 51 achieves a predetermined twisted shape.

[0060] In step S106, the control unit CNT determines whether all dies 51 to be bonded to wafer 6 have been bonded to wafer 6 (its bonding target portion). Typically, approximately 100 dies 51 are bonded to one wafer 6. If not all dies 51 have been bonded to wafer 6, the process returns to step S104, and steps S104 and S105 are repeated until all dies 51 are bonded to wafer 6. On the other hand, if all dies 51 have been bonded to wafer 6, the process proceeds to step S107.

[0061] In step S107, the control unit CNT unloads the wafer 6, on which all the bare dies 51 are attached, from the wafer stage 43 (wafer chuck 433).

[0062] In step S108, the control unit CNT determines whether the die 51 has been bonded to all the wafers 6 being processed in the batch. If the die 51 has not yet been bonded to all the wafers 6, the process returns to step S103, and steps S103, S104, and S105 are repeated until the die 51 is bonded to all the wafers 6. On the other hand, if the die 51 has been bonded to all the wafers 6, the bonding operation terminates. Note that processing is typically performed in batches of 25 wafers 6, but there are also cases where multiple batches are processed consecutively. In this case, the bonding operation of bonding the die 51 to the wafers 6 is repeated under the same bonding control conditions until the wafers 6 or the die 51 (its type) change.

[0063] As described above, according to this embodiment, when the die 51 is bent into a downwardly convex shape and then bonded to the wafer 6, the bonding operation can be controlled so that the bonding shape of the die 51 after bonding to the wafer 6 achieves a predetermined twisted shape. Therefore, in this embodiment, it is possible to improve the bonding reliability between the die 51 and the wafer 6 while suppressing deviations in the bonding position of the die 51 relative to the wafer 6. This is advantageous for the bonding accuracy between the die 51 and the wafer 6.

[0064] In this embodiment, an example of bending the die 51, which is the object of bonding, has been described. However, it is also possible to bend the wafer 6, which is the object of bonding, or to bend both the die 51 and the wafer 6.

[0065] Here, we will refer to Figure 5 The specific construction of the joint 423 used to bend the bare sheet 51 into a downwardly convex shape is described. For example... Figure 5 As shown, in the joint head 423, a cavity portion CA (cavity) is formed on the back side of the holding surface HS (chuck) for holding the die 51, and a pressure adjustment mechanism (not shown) is connected to the cavity portion CA. By adjusting the pressure in the cavity portion CA via the pressure adjustment mechanism, the die 51 held on the holding surface SH can be bent. More specifically, by increasing the pressure in the cavity portion CA, the die 51 can be bent into a shape where the central portion protrudes downward from the peripheral portion (on the wafer 6 side) (downward convex shape). By decreasing the pressure in the cavity portion CA, the die 51 can be bent into a shape where the central portion protrudes upward from the peripheral portion (on the opposite side of the wafer 6) (upward convex shape). Note that the shape of the holding surface SH (chuck) can be pre-deformed, and the bending shape of the die 51 can be adjusted by the pressure in the cavity portion CA. By adjusting the thickness between the holding surface SH and the cavity portion CA, the bending shape of the die 51 can also be changed to an R-shape, a quadratic square, or other shapes. Therefore, it is preferable to have a construction that allows the joint 423 to be selected (replaced) according to the shape of the bare sheet 51 or the target bending shape of the bare sheet 51.

[0066] Figures 6A to 6C Another example of the specific construction of the engagement head 423 for bending the bare sheet 51 into a downwardly convex shape is shown. (Reference) Figure 6A The connector 423 includes multiple vacuum suction sections 428 for clamping the bare die 51. For example... Figure 6B As shown, multiple vacuum adsorption sections 428 serve as multiple holding mechanisms, which respectively hold multiple different portions of the surface 512 of the bare die 51 located on the opposite side of the bonding surface 511 (the surface on the wafer 6 side). Figure 6C As shown, by driving each of the plurality of vacuum adsorption sections 428 in the horizontal direction (a first direction parallel to the mating surface 511 of the bare sheet 51) and the vertical direction (a second direction intersecting the first direction), the bare sheet 51 can be bent into a downwardly convex shape. In particular, in Figures 6A to 6C In the bonding head 423 shown, by driving the vacuum adsorption section 428 horizontally to twist the die 51, the twisted shape of the die 51 when bonding it to the wafer 6 can be reduced. In this embodiment, the case of holding the die 51 by vacuum adsorption in the bonding head 423 has been described. However, the die 51 can also be held by electrostatic force. The bending shape and bending amount of the die 51 can also be adjusted by controlling the driving direction and driving amount of the multiple vacuum adsorption sections 428 respectively. In this embodiment, the bonding head 423 is composed of three vacuum adsorption sections 428, such as... Figures 6A to 6CAs shown. However, in practice, the bare die 51 can be bent precisely by forming a joint 423 with a large number of vacuum adsorption parts 428 arranged in an array.

[0067] <Second Embodiment>

[0068] refer to Figure 7A and Figure 7B The second embodiment will be described below. More specifically, a bonding method will be described, the bonding method comprising a first bonding step of bonding a first bonding object 51a to a wafer 6 and a second bonding step of bonding a second bonding object 51b to the first bonding object 51a bonded to the wafer 6. Also in this embodiment, in order to improve bonding reliability, when bonding the first bonding object 51a or the second bonding object 51b, each of the first bonding object 51a and the second bonding object 51b is bent into a downwardly convex shape (a convex shape facing the wafer 6 side).

[0069] In this embodiment, firstly, as Figure 7A As shown, the bonding control conditions are controlled such that after the first bonding object 51a is bonded to the wafer 6, the bonding shape of the first bonding object 51a achieves a predetermined twisted shape, and the first bonding object 51a is bonded to the wafer 6. Note that in Figure 7A In this context, the predetermined twisted shape is pillow-shaped, but the predetermined twisted shape is not limited to this. It can also be barrel-shaped, a shape with a magnification component, an inclined shape, a shape with a magnification difference between the vertical and horizontal directions, etc.

[0070] Then, as Figure 7B As shown, a second bonding object 51b is bonded to a first bonding object 51a (i.e., the object to be bonded on the bonding target object) that is bonded to the wafer 6. More specifically, bonding control conditions are controlled such that after the second bonding object 51b is bonded to the first bonding object 51a on the wafer, the bonding shape of the second bonding object 51b matches a predetermined twist shape controlled when bonding the first bonding object 51a, and the second bonding object 51b is bonded to the first bonding object 51a. Typically, the first bonding object 51a and the second bonding object 51b differ in terms of die thickness, die size, die material, and stress on the semiconductor elements formed on the die. Therefore, the bonding control conditions for bonding the second bonding object 51b to the first bonding object 51a are different from the bonding control conditions for bonding the first bonding object 51a to the wafer 6.

[0071] According to this embodiment, while maintaining high bonding reliability, it is possible to bond the first bonding object 51a and the second bonding object 51b while reducing the deviation of the bonding position of the second bonding object 51b relative to the first bonding object 51a.

[0072] <Third Embodiment>

[0073] refer to Figure 8A and Figure 8B The third embodiment will be described. More specifically, a bonding method will be described, the method comprising a formation step of forming (manufacturing) a semiconductor element 601 on a wafer 6 and a bonding step of bonding a die 51 to the semiconductor element 601 formed on the wafer 6. Also in this embodiment, in order to improve bonding reliability, when bonding the die 51, the die 51 is bent into a downwardly convex shape (a convex shape facing the wafer 6 side).

[0074] In this embodiment, firstly, as Figure 8A As shown, a semiconductor element 601 is formed on wafer 6 according to the twisted shape of wafer 51 after bonding. Note that in Figure 8A In this process, the twisted shape is pillow-shaped, but it is not limited to this. It can also be barrel-shaped, a shape with a magnification component, a tilted shape, or a shape with a magnification difference between the vertical and horizontal directions. The semiconductor element 601 (its shape) can be twisted by a semiconductor exposure device during the patterning process.

[0075] Then, as Figure 8B As shown, a bare die 51 is bonded to a semiconductor element 601 formed on a wafer 6. More specifically, bonding control conditions are controlled such that after the bare die 51 is bonded to the semiconductor element 601 on the wafer, the bonding shape of the bare die 51 matches the twisted shape (predetermined twisted shape) of the semiconductor element 601, and the bare die 51 is bonded to the semiconductor element 601. In other words, in this embodiment, a semiconductor element 601 is formed on the wafer 6 such that the shape of the semiconductor element 601 formed on the wafer 6 achieves the bonding shape (predetermined twisted shape) of the bare die 51 bonded to the semiconductor element 601 on the wafer.

[0076] According to this embodiment, it is possible to bond the semiconductor element 601 and the die 51 while maintaining high bonding reliability and reducing the deviation of the bonding position of the die 51 relative to the semiconductor element 601 formed on the wafer 6.

[0077] <Fourth Embodiment>

[0078] refer to Figures 9A to 9CThe fourth embodiment will now be described. The bonding method described in this embodiment includes three bonding steps. More specifically, the bonding method according to this embodiment includes: a first bonding step of bonding a first bonding object 51a to a first substrate 6a; and a second bonding step of bonding a second bonding object 51b to a second substrate 6b. Furthermore, in addition to the first and second bonding steps, the bonding method according to this embodiment also includes a third bonding step of bonding the first substrate 6a to which the first bonding object 51a is bonded and the second substrate 6b to which the second bonding object 51b is bonded.

[0079] In this embodiment, firstly, as Figure 9A As shown, the bonding control conditions are controlled such that after the first bonding object 51a is bonded to the first substrate 6a, the bonding shape of the first bonding object 51a achieves a predetermined twisted shape, and the first bonding object 51a is bonded to the first substrate 6a. Thus, a first reconstructed substrate RCS1 is manufactured, which is the first substrate 6a on which the first bonding objects 51a are arranged. Note that... Figure 9A The predetermined twist shape is pillow-shaped, but it is not limited to this. It can also be barrel-shaped, a shape with a magnification component, an inclined shape, or a shape with a magnification difference between the vertical and horizontal directions. However, since the first reconstruction substrate RCS1 is ultimately inverted in an axisymmetric manner and bonded to the second reconstruction substrate RCS2 (described later), the predetermined twist shape is preferably an axisymmetric shape about the inversion axis. Note that the reconstruction substrate can be a form in which the bonding object is bonded to the substrate, sealed with a mold material, and then the substrate is removed. In this case, a step is required to remove the mold material deposited on the surface of the bonding object to expose the surface of the bonding object (the surface of the semiconductor element), etc.

[0080] Then, as Figure 9B As shown, the bonding control conditions are controlled such that after the second bonding object 51b is bonded to the second substrate 6b, the bonding shape of the second bonding object 51b achieves a predetermined twisted shape, and the second bonding object 51b is bonded to the second substrate 6b. Here, the predetermined twisted shape is a twisted shape that matches the twisted shape controlled when the first bonding object 51a is bonded to the first substrate 6a. In this way, a second reconstructed substrate RCS2 is manufactured, which is a second substrate 6b on which the second bonding objects 51b are arranged. Typically, the first bonding object 51a and the second bonding object 51b differ in terms of die thickness, die size, die material, and stress on the semiconductor elements formed on the die. Therefore, the bonding control conditions for bonding the second bonding object 51b to the second substrate 6b are different from the bonding control conditions for bonding the first bonding object 51a to the first substrate 6a.

[0081] Then, as Figure 9CAs shown, the first reconstructed substrate RCS1 and the second reconstructed substrate RCS2 are axially symmetrically reversed and joined together. More specifically, the first substrate 6a and the second substrate 6b are aligned and joined together, such that the first joining object 51a on the first substrate and the second joining object 51b on the second substrate are joined together.

[0082] According to this embodiment, it is possible to join the first joining object 51a and the second joining object 51b while maintaining high joining reliability and reducing the joining position deviation of each of the first joining object 51a and the second joining object 51b.

[0083] <Fifth Embodiment>

[0084] A method for manufacturing articles (semiconductor integrated circuit elements, liquid crystal display elements, microelectromechanical systems (MEMS), etc.) using bonding equipment BD in the above embodiments will be described. The article is manufactured through the following steps: a preparation step of preparing a bonding object and a bonding target object; a bonding step (bonding method (bonding operation)) of bonding the bonding object to the bonding target object using bonding equipment BD; and a manufacturing step of manufacturing the article by processing the bonding target object to which the bonding object is bonded in another known process. Other known processes include probing, cutting, bonding, and packaging. Compared with conventional methods, the article manufacturing method according to this embodiment has advantages in at least one of the following: article performance, quality, productivity, and production cost.

[0085] While this disclosure has been described with reference to exemplary embodiments, it should be understood that this disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims should be given the broadest interpretation to cover all such modifications and equivalent structures and functions.

Claims

1. A joining device, the joining device performing a joining operation to join a joining object to a joining target object, comprising: A driving unit configured to implement a driving action that causes the joining object to join the joining target object; and A control unit configured to control the joining operation such that, after the joining object is joined to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape.

2. The device according to claim 1, wherein The control unit includes: Acquisition unit, the acquisition unit being configured to acquire the predetermined twisted shape; and A calculation unit configured to calculate control conditions related to the joining operation, so that the joining shape of the joining object achieves the predetermined twisted shape acquired by the acquisition unit.

3. The device according to claim 2, wherein, The joining operation includes joining the joining object to the joining target object while the joining object is bent into a convex shape on the side facing the joining target object.

4. The device according to claim 3, wherein, The control conditions include at least one of the following: the amount of bending of the joining object when joining the joining object to the joining target object; the bending shape of the joining object when joining the joining object to the joining target object; the relative velocity between the joining object and the joining target object when joining the joining object to the joining target object; and the holding force of the joining object when joining the joining object to the joining target object.

5. The device according to claim 2, wherein, The calculation unit calculates the control conditions based on at least one of the thickness of the bonding object, the size of the bonding object, the material of the bonding object, and the stress of the semiconductor element formed on the bonding object.

6. The device according to claim 1, further comprising: A first holding unit, configured to hold the mating object; and A second holding unit, configured to hold the engagement target object. The driving unit drives at least one of the first holding unit and the second holding unit.

7. The device according to claim 6, wherein, When the joining object is joined to the joining target object, the first retaining unit causes the joining object to bend into a convex shape toward the side of the joining target object.

8. The device according to claim 7, wherein, The first retaining unit includes a plurality of retaining mechanisms, which respectively retain a plurality of different portions of the surface of the joining object located on the opposite side of the joining surface on one side of the joining target object, and by driving each of the plurality of retaining mechanisms along a first direction parallel to the joining surface and a second direction intersecting the first direction, the joining object is bent into a convex shape toward the side of the joining target object.

9. The device according to claim 1, wherein, The bonding object is a bare die including semiconductor elements, and The target object for bonding is a substrate.

10. The device according to claim 1, wherein, The bonding object is a bare die including semiconductor elements, and The bonding target is a semiconductor element formed on a substrate.

11. The device according to claim 1, wherein, The bonding object is a first bonding object bonded to the first reconstructed substrate, and The bonding target is a second bonding object that is bonded to a second reconstruction substrate that is different from the first reconstruction substrate.

12. A joining method for joining a joining object to a joining target object, the joining method comprising: Prepare the joining object and the joining target object; as well as The joining object is joined to the joining target object such that, after the joining object is joined to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape.

13. A joining method, the joining method comprising: The first joining object is joined to the joining target object such that after the first joining object is joined to the joining target object, the joining shape of the first joining object achieves a predetermined twisted shape; as well as The second joining object is joined to the first joining object such that, after the second joining object is joined to the first joining object on the joining target object, the joining shape of the second joining object achieves the predetermined twisted shape.

14. A joining method, the joining method comprising: Semiconductor elements are formed on a substrate; and The bonding object is bonded to the semiconductor element such that, after the bonding object is bonded to the semiconductor element on the substrate, the bonding shape of the bonding object achieves a predetermined twisted shape. During the formation process, the semiconductor element is formed on the substrate such that the shape of the semiconductor element formed on the substrate achieves the predetermined twisted shape.

15. A joining method, the joining method comprising: The first bonding object is bonded to the first substrate such that after the first bonding object is bonded to the first substrate, the bonding shape of the first bonding object achieves a predetermined twisted shape; The second bonding object is bonded to the second substrate such that, after the second bonding object is bonded to the second substrate, the bonding shape of the second bonding object achieves the predetermined twisted shape; as well as The first substrate and the second substrate are joined such that the first bonding object on the first substrate and the second bonding object on the second substrate are joined.

16. A method for manufacturing an article of manufacture, the method comprising: Prepare the joining object and the joining target object; A joining device is used to join the joining object to the joining target object, the joining device performing the joining operation of joining the joining object to the joining target object, the joining device comprising: A driving unit, configured to implement a drive such that the joining object joins the joining target object; and A control unit, configured to control the joining operation such that, after the joining object is joined to the joining target object, the joining shape of the joining object achieves a predetermined twisted shape; and Articles are manufactured by processing the joining target object to which the joining objects are joined.

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