Bonding device and object manufacturing method

Abstract

To provide a technique advantageous for reducing positional displacement of a first object with respect to a second object due to poor bonding between the first object and the second object, and preventing the first object from falling.SOLUTION: A bonding device that bonds a first object and a second object, includes: a first holding part that holds the first object by suction; a second holding part that holds the second object; a driving mechanism that performs an approaching operation of bringing the first holding part and the second holding part close to each other so as to bring the first object and the second object into contact with each other, and a separating operation of moving the first holding part and the second holding part away from each other after the approaching operation; and a control part that controls an operation of the driving mechanism and a holding force of the first holding part for holding the first object. The control part causes the drive mechanism to perform the separation operation while causing the first holding part to apply the holding force to the first object.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a bonding device and an article manufacturing method.

Background Art

[0002] In a bonding device for bonding a die to a substrate, bonding failure between the die and the substrate may occur. When bonding failure occurs, the positions of the die and the substrate shift when the die contacts the substrate or when the stage holding the substrate moves. Such misalignment can cause product defects, die drop, device stoppage or failure, and may lead to a decrease in productivity.

[0003] Patent Document 1 describes determining the quality of a bonding operation from the difference between the position where a bump of a semiconductor device contacts a substrate and the position at the completion of the pressing operation of the semiconductor device against the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, Patent Document 1 does not assume the case where the die (first object) is separated from the substrate (second object) during the bonding operation. The present invention provides an advantageous technique for reducing the misalignment of the first object with respect to the second object and preventing the fall of the first object due to bonding failure between the first object and the second object.

Means for Solving the Problems

[0006] According to one aspect of the present invention, there is provided a bonding device for bonding a first object and a second object, comprising: a first holding portion for sucking and holding the first object; a second holding portion for holding the second object; a driving mechanism for performing an approaching operation of bringing the first holding portion and the second holding portion closer to each other so that the first object and the second object are brought into contact with each other, and a separating operation of separating the first holding portion and the second holding portion from each other after the approaching operation; and a control unit for controlling the operation of the driving mechanism and the holding force of the first object by the first holding portion, wherein the control unit causes the driving mechanism to perform the separating operation while applying the holding force of the first object by the first holding portion.

Effects of the Invention

[0007] According to the present invention, it is possible to provide an advantageous technique for reducing the displacement of the first object with respect to the second object and preventing the first object from falling due to poor bonding between the first object and the second object.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] FIG. 1 is a diagram showing the configuration of a bonding apparatus for bonding a first object and a second object in an embodiment. In this specification and the drawings, directions are indicated in an XYZ coordinate system with the horizontal plane as the XY plane. Generally, the substrate 6 is placed on the substrate stage 43 so that its surface is parallel to the horizontal plane (XY plane). Therefore, hereinafter, in the plane along the surface of the substrate 6 placed on the substrate stage 43, the directions orthogonal to each other are defined as the X-axis and the Y-axis, and the direction perpendicular to the X-axis and the Y-axis is defined as the Z-axis. Further, hereinafter, the directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are referred to as the X-direction, Y-direction, and Z-direction, respectively.

[0011] Also, in this specification and the drawings, the suffix added to the reference numeral is used when referring to a specific one among the things indicated by the reference numeral. For example, as will be described later, the bonding apparatus shown in FIG. 1 includes a vermirror 432, and the vermirror 432 may include vermirrors 432a and 432b for different directions (see FIG. 2). When it is necessary to specify the vermirror for each direction, a reference sign with a suffix such as vermirror 432a or vermirror 432b is used. On the other hand, when it is not necessary to specify which vermirror it is, a reference sign without a suffix such as vermirror 432 is used.

[0012] The first object may be a die on which a semiconductor device is manufactured and diced, and the second object may be a substrate (wafer) on which a semiconductor device is manufactured, but the first and second objects are not limited thereto. For example, the first object may be a silicon interposer with wiring formed on a silicon substrate, a glass interposer with wiring formed on a glass substrate, or an organic interposer with wiring formed on an organic panel (PCB). Alternatively, the first object may be, for example, a substrate on which a semiconductor device is manufactured and to which several dice on which semiconductor devices have been manufactured are already bonded. Alternatively, the first object may be, for example, a stack of several already diced dice, a small piece of material, an optical element, MEMS, a structure, etc.

[0013] Further, the present invention does not limit the bonding method between the first object and the second object to a specific bonding method. For example, any bonding method such as bonding with an adhesive, temporary bonding with a temporary adhesive, bonding by hybrid bonding, atomic diffusion bonding, vacuum bonding, bump bonding, etc. may be adopted, and various temporary bonding and permanent bonding methods can be used.

[0014] Hereinafter, industrial application examples of the bonding device in the present disclosure will be described.

[0015] The first application example is the manufacture of a stacked memory. When the bonding device is applied to the manufacture of a stacked memory, the first object may be a diced memory die, and the second object may be a substrate on which a semiconductor device, which is a memory, is manufactured. For example, when 8-layer stacking is performed, in the bonding of the 8th layer, the second object will be a substrate on which 6-layer memory dice are already bonded on the substrate. Note that the top layer may also be a driver die for driving the memory.

[0016] The second application example is the heterogeneous integration of a processor. This is a method of manufacturing a processor by applying a process optimal for each element to manufacture each element on a separate substrate and then bonding them together, as opposed to the conventional mainstream of integrating a logic circuit and SRAM in one semiconductor element to form a SoC. This can achieve cost reduction and yield improvement of the processor. When a bonding apparatus is applied to heterogeneous integration, the first object can be SRAM that has been singulated after probing, or dies such as antennas and drivers, and the second object can be a substrate on which a memory, which is a semiconductor device, has been manufactured. Usually, different dies are sequentially bonded to the substrate. For example, when bonding starts from SRAM, when bonding the next die after the SRAM, the one with the SRAM die bonded to the logic substrate becomes the second object.

[0017] The third application example is 2.5D bonding using a silicon interposer. A silicon interposer is one in which wirings are formed on a silicon wafer. 2.5D bonding is a method of bonding singulated dies using this silicon interposer to achieve electrical bonding between the dies. When a bonding apparatus is applied to die bonding of a silicon interposer, the first object can be a singulated die, and the second object can be a silicon interposer with wirings formed on a silicon wafer. Usually, since multiple types of dies are bonded to the silicon interposer, the second object includes those with some dies already bonded to the silicon interposer.

[0018] The fourth application example is 2.1D bonding using an organic interposer or a glass interposer. An organic interposer is one in which wirings are formed on an organic panel (PCB substrate, CCL substrate) used as a package substrate, and a glass interposer is one in which wirings are formed on a glass panel. 2.1D bonding is to bond dies separated into individual pieces to this organic interposer or glass interposer, and perform electrical bonding between the dies with the wirings on the interposer. When the bonding apparatus is applied to die bonding to an organic interposer, the first object can be a separated die, and the second object can be an organic panel on which wirings are formed. When the bonding apparatus is applied to die bonding of a glass interposer, the first object can be a separated die, and the second object can be a glass panel on which wirings are formed. Usually, since a plurality of types of dies are bonded to an organic interposer or a glass interposer, the second object includes those to which several dies have already been bonded to the organic interposer or the glass interposer.

[0019] The fifth application example is heterogeneous substrate bonding. For example, in an infrared image sensor, InGaAs is known as a high-sensitivity material. It has been proposed to manufacture a high-sensitivity and high-speed infrared image sensor by using InGaAs for a sensor unit that receives light and using silicon on which a high-speed processing die can be formed for a logic circuit unit that extracts data. However, for InGaAs crystals, only small-diameter substrates such as 4 inches have been mass-produced, and they are smaller than the 300 mm that is mainstream for silicon wafers. Therefore, a method has been proposed to bond a separated InGaAs substrate onto a 300 mm silicon wafer on which a logic circuit is formed. Bonding substrates that are different from each other in material and size in this way is called heterogeneous substrate bonding. When the bonding apparatus is applied to heterogeneous substrate bonding, the first object can be a small piece of a material such as InGaAs, and the second object can be a large-diameter substrate such as a silicon wafer. Note that the small piece of material is a sliced crystal, but it is desirable to cut it out into a square shape.

[0020] In the following description, for the purpose of providing specific examples, the first object is described as a die on which a semiconductor device is manufactured and singulated, and the second object is described as a substrate (wafer) on which a semiconductor device is manufactured.

[0021] <First Embodiment> FIG. 1 is a diagram showing the configuration of a bonding apparatus in an embodiment. In FIG. 1, the direction perpendicular to the paper surface is the X direction, the right direction on the paper surface is the Y direction, and the upward direction on the paper surface is the Z direction. The bonding apparatus may include a pickup unit 3 and a bonding unit 4 mounted on a base 1 vibrationally isolated by a mount 2. The bonding apparatus bonds die 51, which is a singulated first object, arranged in parallel on a dicing tape adhered to a dicing frame 5, at an arbitrary position on a substrate 6, which is a second object. In the example of FIG. 1, the pickup unit 3 and the bonding unit 4 are mounted on the same base, but the pickup unit 3 and the bonding unit 4 may be mounted on separate bases.

[0022] The pickup unit 3 includes a pickup head 31 and a release head 32. The release head 32 peels the dicing tape from the die 51, and the pickup head 31 adsorbs the die 51 from which the dicing tape has been peeled by the release head 32. The pickup head 31 rotates around the Y axis so that the adsorbed die 51 faces upward, and delivers the die 51 to a bonding head 423 (first holding unit). A suction mechanism 424 for sucking and holding the die 51 is configured in the bonding head 423.

[0023] The bonding unit 4 includes a stage base plate 41 and an upper base 42, and a substrate stage 43 is mounted on the stage base plate 41. The substrate stage 43 can be driven in the XY direction and rotated around the Z axis by a drive unit such as a linear motor (not shown). Note that it is not essential to perform the rotation operation on the substrate stage 43, and it may be performed on the bonding head 423 side.

[0024] The substrate stage 43 is equipped with a die observation camera 431. The die observation camera 431 is configured to measure the positions of the feature points of the die, which is the first object, the outer dimensions of the die, and the distances in the height direction of a plurality of points on the measurement surface. Therefore, it is possible to measure the position, outer dimensions, and flatness of the die held by the bonding head 423 using the die observation camera 431.

[0025] A bar mirror 432 is arranged on the side surface of the substrate stage 43. The bar mirror 432 serves as the target of the interferometer 422.

[0026] Further, the substrate stage 43 is equipped with a substrate chuck 433 (second holding portion) for chucking (holding) the substrate 6, which is the second object. The chucking method of the substrate by the substrate chuck 433 may be a vacuum suction method or an electrostatic adsorption method.

[0027] The upper base 42 supports a substrate observation camera 421 for measuring flatness by measuring the positions of the feature points on the substrate 6 and the Z-direction distances of a plurality of points. The upper base 42 also supports an interferometer 422 for measuring the position of the substrate stage 43 and a bonding head 423 for holding the die 51, which is the first object transferred from the pickup head 31. The substrate observation camera 421 can be a camera that uses infrared light as the measurement light source. The substrate observation camera 421 is configured to be able to measure, for example, the element patterns or marks formed on or inside the substrate 6.

[0028] The drive mechanism 450 is configured to drive the substrate chuck 433 in the Z direction (Z drive) in order to perform the bonding operation between the die 51 and the substrate 6. The drive mechanism 450 may be configured to Z drive the substrate stage 43. In the present embodiment, the bonding operation may include a proximity operation of bringing the bonding head 423 and the substrate chuck 433 closer to each other so that the die 51 and the substrate 6 are in contact with each other, and a separation operation of moving the bonding head 423 and the substrate chuck 433 away from each other after the proximity operation. By driving the substrate chuck 433 in the +Z direction by the drive mechanism 450, the proximity operation can be performed, and by driving the substrate chuck 433 in the -Z direction, the separation operation can be performed. Alternatively, the proximity operation may be performed by driving the bonding head 423 in the +Z direction, and the separation operation may be performed by driving the bonding head 423 in the -Z direction. Alternatively, the bonding operation may be performed by Z driving both the bonding head 423 and the substrate chuck 433. That is, the drive mechanism 450 may be a relative drive mechanism that relatively drives the bonding head 423 and the substrate chuck 433 so that the distance between the die 51 and the substrate 6 changes. When driving the substrate chuck 433 by such a relative drive mechanism, the position of the substrate chuck 433 in the Z direction is feedback-controlled in real time while being measured by the interferometer 422.

[0029] Also, in the above description, it is assumed that the pickup head 31 is configured to rotate and transfer the die to the bonding head 423. However, by providing two or more die holding portions and relaying the die between the die holding portions, the die may be transferred to the bonding head 423, or the bonding head 423 may be configured to receive the die by the drive mechanism of the bonding head 423.

[0030] Also, for improving productivity, a plurality of pickup portions, a plurality of pickup heads, a plurality of release heads, and a plurality of bonding heads may be arranged.

[0031] The control unit 441 comprehensively controls each part of the bonding apparatus. In particular, the control unit 441 can control the operation of the drive mechanism 450 and the suction force (holding force) applied to the die by the bonding head 423 (suction mechanism 424). The control unit 441 is composed of a computer (information processing apparatus) having a processor such as a CPU (Central Processing Unit) and a storage unit such as a memory. Note that the control unit 441 may be arranged inside the housing of the bonding apparatus or outside the housing. The control unit 441 arranged outside the housing of the bonding apparatus may be realized by a computer that functions as a control server network-connected to the bonding apparatus, for example.

[0032] FIG. 2 is a view of the substrate stage 43 as seen from the positive Z-axis direction. The substrate 6 is held by the substrate chuck 433. The bar mirror 432 may include at least two bar mirrors so as to be able to measure the positions of the substrate 6 in the X direction, Y direction, and the rotational directions about the Z-axis respectively. The bar mirror 432a serves as a target for the interferometer 422a that measures the position in the X direction and the interferometer 422c that measures the amount of rotation about the Z-axis by the difference from the interferometer 422a. The bar mirror 432b serves as a target for the interferometer 422b that measures the position in the Y direction. The interferometer 422 measures the position of the substrate stage 43 in the X direction, Y direction, and the amount of rotation about the Z-axis in real time. The control unit 441 performs feedback control on the stage drive unit in real time based on the measurement results by the interferometer 422, and positions the substrate stage 43 with high precision. Thus, the positioning in this embodiment is performed by highly accurate position measurement by an interferometer and feedback control based on the result.

[0033] Next to the substrate chuck 433, a reference plate 434 with a plurality of marks (including marks 434a, 434b, and 434c) drawn thereon is arranged. The reference plate 434 desirably has a low coefficient of thermal expansion and the marks are drawn with high positional accuracy. In one example, the reference plate 434 may be one on which marks are drawn using a drawing method of a semiconductor lithography process on a quartz substrate. The reference plate 434 is desirably configured to be at the same height as the surface of the substrate 6 and be observable by the substrate observation camera 421, but this is not the case when a separate camera for observing the reference plate is configured. The substrate stage 43 may include a coarse movement stage capable of driving a large range and a fine movement stage arranged on the coarse movement stage and capable of driving with high precision in a small range. In that case, the die observation camera 431, the bar mirror 432, the substrate chuck 433, and the reference plate 434 need to be fixed on the fine movement stage for high-precision positioning.

[0034] A method for guaranteeing the origin position, magnification, directions (rotation) of the X-axis and Y-axis, and orthogonality of the substrate stage 43 using the reference plate 434 will be described. The mark 434a is observed with the substrate observation camera 421, and the measured value of the interferometer when the mark 434a comes to the center of the acquired image of the camera is set as the origin of the substrate stage 43. Next, the mark 434b is observed with the substrate observation camera 421, and the direction of the Y-axis and the Y magnification of the substrate stage 43 are determined from the measured value of the interferometer when the mark 434b comes to the center of the acquired image of the camera. Next, the mark 434c is observed with the substrate observation camera 421, and the direction of the X-axis and the X magnification of the substrate stage 43 are determined from the measured value of the interferometer when the mark 434c comes to the center of the acquired image of the camera. That is, calibration of the axis direction and orthogonality is performed with the direction from the mark 434b to the mark 434a of the reference plate 434 as the Y direction and the direction from the mark 434c to the mark 434a as the X direction. Also, calibration is performed with the interval between the mark 434b and the mark 434a as the scale reference in the Y direction and the interval between the mark 434c and the mark 434a as the scale reference in the X direction. Since the measured value of the interferometer fluctuates due to changes in the refractive index of the interferometer optical path caused by air pressure fluctuations and temperature fluctuations, it is desirable to perform calibration at an arbitrary timing to guarantee the origin position, magnification, rotation, and orthogonality of the substrate stage. In addition, in order to reduce the fluctuation of the measured value of the interferometer, it is desirable that the temperature of the substrate stage space is controlled by a temperature control chamber.

[0035] In the above example, the configuration is such that the reference plate 434 on the substrate stage 43 is observed with the substrate observation camera 421. Instead of this form, the reference plate 434 may be attached to the upper base 42 and observed with the die observation camera 431. With that configuration as well, the origin position, magnification, rotation, and orthogonality of the substrate stage 43 can be guaranteed.

[0036] In addition, in the above example, calibration is performed by observing the reference plate 434. Instead, for example, calibration may be performed by a butting operation against a reference surface, or highly accurate positioning may be performed using a position measurement unit such as a white interferometer whose absolute value is guaranteed.

[0037] With reference to FIGS. 3 and 4, the bonding method in the first embodiment will be described. FIG. 3 is a diagram illustrating the measurement surface of the die 51, and FIG. 4 is a flowchart of the bonding method. In FIG. 3, the direction perpendicular to the paper surface is the X direction, the right direction of the paper surface is the Y direction, and the upward direction of the paper surface is the Z direction. The die 51 has a bonding surface 51a and a non-bonding surface 51b on the opposite side thereof. The bonding surface 51a has a bonding surface element pattern 501 and a bonding surface alignment mark 502. The non-bonding surface 51b has an array pattern 503 of through vias.

[0038] In S1001, the control unit 441 controls a substrate transfer device (not shown) to transfer the substrate 6 into the bonding device. Since foreign matter adhering to the bonding surface of the die may cause a bonding failure, the inside of the bonding device has a clean space of about class 1. In order to keep the substrate 6 clean as well, the substrate 6 is contained in a container with high sealing and high cleanliness such as a FOUP, and is transferred into the device from the container. Further, in order to increase the cleanliness, the substrate 6 may be washed in the bonding device after the substrate is transferred. Also, a pretreatment for bonding is performed. For example, when bonding is performed using an adhesive, the adhesive is applied to the substrate 6. When bonding is performed by hybrid bonding, a process of activating the substrate surface is performed. In a pre-alignment unit (not shown), the rotational direction of the substrate 6 is adjusted based on a notch or an orientation flat formed on the substrate 6, and a rough positioning of the substrate 6 is performed based on the outer shape of the substrate. Thereafter, the substrate 6 is held by a substrate chuck 433 on a substrate stage 43.

[0039] In S1002, the control unit 441 measures the mounting position of the substrate 6 using the substrate observation camera 421. The focus adjustment of the substrate observation camera 421 may be performed by a focus adjustment mechanism provided in the substrate observation camera 421, or may be performed by Z-driving the substrate 6 by the Z-driving mechanism of the substrate stage 43. The alignment measurement can be performed by measuring alignment marks previously formed on the substrate 6. When no alignment marks are formed on the substrate 6, alignment measurement is performed by measuring feature points whose positions can be specified. The control unit 441 measures the position of the feature points by measuring the image position of the projected feature points with respect to the center of the image acquired by imaging with the substrate observation camera 421. In order to measure with high precision with respect to the reference point of the bonding apparatus, the substrate stage 43 is driven in advance so that the mark formed on the reference plate 434 enters the field of view of the substrate observation camera 421, and the substrate observation camera 421 measures the position of the mark on the reference plate 434. By determining the offset amount with respect to the measurement position measured by the substrate observation camera 421 from the driving position of the substrate stage 43 at that time and the mark position measured by the substrate observation camera 421, the position can be measured with high precision with respect to the reference point of the bonding apparatus. Here, the reference point of the apparatus generally refers to the specific mark position on the reference plate, but it may be another location as long as it is a reference position. Since the measurement range in the rotation direction of the interferometer is narrow, the amount of rotation that can be corrected by the substrate stage is small. Therefore, when the amount of rotation of the substrate is large, it is desirable to correct the rotation and re-hold the substrate. When the substrate is re-held, it is necessary to measure the mounting position of the substrate again. Also, it is desirable to measure the surface position of the substrate using a height measurement unit (not shown) that measures the surface position of the bonding surface of the substrate during this process. This is because there is variation in the thickness of the substrate, and the position of the substrate surface is important in order to accurately control the gap between the die (first object) and the substrate (second object) during the bonding operation.

[0040] Since the origin position, magnification, directions (rotation) of the X-axis and Y-axis, and orthogonality of the substrate stage 43 are guaranteed using the reference plate 434, the position of the mounted substrate 6 is measured with respect to the origin position, X-axis, and Y-axis of the substrate stage 43. On the substrate 6, semiconductor devices having functions as bonding targets are repeatedly manufactured in a certain period within the substrate. Since multiple layers are manufactured with high precision positioning in a semiconductor manufacturing apparatus, these semiconductor devices are generally repeatedly arranged at a cycle with nano-level accuracy. Therefore, in the substrate alignment here, it is not necessary to measure all the bonding target positions where semiconductor devices are formed. For example, input the arrangement information of the semiconductor devices in advance, measure the positions of the feature points of the semiconductor devices at three or more locations less than the bonding targets, and execute statistical processing. Based on the results of the statistical processing, the origin position of the repeated arrangement of the bonding targets, the rotation amounts in the directions of the X-axis and Y-axis, the orthogonality, and the magnification error of the repetition period are calculated.

[0041] Also, it is desirable that the substrate chuck 433 has a mechanism for temperature control of the substrate. This is because the thermal expansion coefficient of the silicon substrate is 3 ppm / °C. In the case of a 300 mm substrate, when the temperature rises by 1°C, the position moves by 150 mm × 0.000003 = 0.00045 mm = 450 nm at the outermost periphery. If the bonding position moves after the substrate alignment, bonding cannot be performed with high positional accuracy. Therefore, it is desirable to control the temperature of the substrate and stabilize it at 0.1°C or less.

[0042] In addition, when the second object is an interposer on which wirings are formed, instead of the arrangement of the semiconductor devices, the arrangement of the repeatedly formed wirings is measured. In the case of a substrate or panel without a pattern, substrate alignment is not performed.

[0043] Above, the movement of the substrate as the second object has been described. Next, the movement of the die as the first object that is carried out in parallel will be described.

[0044] In S2001, a dicing frame on which dice diced by a dicing machine are arranged is carried into the dicing tape. Conventionally, the dicing frame was transported in an unsealed magazine. However, as described above, if foreign matter adheres to the bonding surface, bonding failure occurs, so it is necessary to transport it in a container with high sealing and high cleanliness. In order to increase the cleanliness, the dice on the dicing frame may be cleaned in the bonding apparatus. The dicing frame is roughly positioned in the rotational direction and the shift position based on the outer shape of the dicing frame by a pre-alignment unit (not shown).

[0045] In S2002, the die 51 is picked up. The control unit 441 moves the pickup head 31 and the release head 32 to the position of the die 51 to be picked up. While adsorbing the die 51 with the pickup head 31, the release head 32 peels the die 51 from the dicing tape, and the pickup head 31 holds the die 51.

[0046] In S2003, the control unit 441 controls the pickup head 31 to transfer the die 51 to the bonding head 423. The bonding head 423 sucks and holds the die 51 by the suction mechanism 424. When the die 51 is picked up in S2002, the semiconductor device surface is on the pickup head side, but on the bonding head 423, it is held so that the semiconductor device surface is on the side opposite to the bonding head 423. The transfer can be performed by moving the pickup head 31 to the position of the bonding head 423. Alternatively, the transfer may be performed by relaying the die 51 at one or more holding parts between the pickup head 31 and the bonding head 423. Also, pre-treatment for bonding can be performed during the transfer. Examples of the pre-treatment include cleaning the die. In the case of bonding with an adhesive, application of the adhesive can be performed as the pre-treatment. In the case of hybrid bonding, a treatment for activating the surface can be performed as the pre-treatment.

[0047] As described above, the substrate 6, which is the second object, and the die 51, which is the first object, are each held by the holding portion.

[0048] Subsequently, in S1003, the position of the die 51 on the bonding head 423 is measured. Specifically, the control unit 441 drives the substrate stage 43 so that the feature points of the die 51 enter the field of view of the die observation camera 431. The feature points can be element patterns or alignment marks within the die bonding surface 51a. Alternatively, all or part of the measured outer dimension shape of the die 51 may be treated as the feature points. Focus adjustment can be performed, for example, by the focus adjustment mechanism of the die observation camera 431. Alternatively, the focus adjustment may be performed by Z-driving the die 51 by the Z-driving mechanism of the bonding head 423. Alternatively, the focus adjustment may be performed by Z-driving the die observation camera 431 by the Z-driving mechanism of the substrate stage 43 on which the die observation camera 431 is mounted. Since the scribe line on which the alignment marks used for alignment in the semiconductor manufacturing process are formed by dicing has been removed from the die, there are many cases where no alignment marks for alignment are arranged on the die. Therefore, the end portions of the arrangement of pads or bumps arranged on the die bonding surface 51a, regions with an irregular arrangement where the position can be specified, or the outer shape of the die 51 are measured as feature points. The die observation camera 431 measures the position of the feature points by measuring the image position of the projected feature points with respect to the center of the acquired image. For the position measurement of the die, it is desirable to measure a plurality of feature points within the die and also measure the rotation amount of the die. To measure a plurality of feature points, measurement may be performed while driving the substrate stage 43, or the positions of a plurality of feature points within the field of view may be measured with a wider field of view of the die observation camera 431. The rotation of the die can be corrected by the rotation of the substrate stage 43 during bonding. However, since the measurement range in the rotation direction of the interferometer is narrow, when the rotation amount of the die is large, it is desirable to correct the rotation and re-hold the die. When the die is re-held, it is necessary to measure the position of the die again. Also, it is desirable to measure the surface position of the die 51 using a height measurement unit (not shown) that measures the surface position of the bonding surface 51a of the die 51 during this process. This is because there is variation in the thickness of the die, and the position of the die surface is important for precisely controlling the gap between the die and the substrate during the bonding operation.Further, it is desirable to measure the heights of a plurality of positions in the die 51 and adjust the posture of the die or the substrate with a tilt mechanism (not shown) during bonding. The tilt mechanism can be provided in any of the substrate stage 43, the substrate chuck 433, and the bonding head 423. In this process, the relationship between the measured position of the feature point of the die 51 and the outer dimension information of the die itself is established. Establishing the relationship means establishing the position relationship between the outer shape of the die 51 and the element pattern or alignment mark in the die bonding surface 51a. The control unit 441 stores the established information in a predetermined storage device inside or outside the apparatus.

[0049] Thus, in S1003, the element pattern or alignment mark in the die bonding surface 51a, which is a feature point of the die 51, and all or part of the outer shape of the die 51 are measured. Then, the relationship between the position of the feature point of the die 51 and the outer dimension information of the die itself is established, and the information is stored. Alternatively, in this process, instead of performing such measurement, these information regarding the die to be inserted may be input from outside the bonding apparatus and stored in the bonding apparatus.

[0050] In S1004, the control unit 441 drives the substrate stage 43 so that the die 51 is positioned above the bonding position on the substrate. The control unit 441 measures the position of the substrate stage 43 with the interferometer 422 and performs feedback control on the substrate stage 43 in real time to position the substrate stage 43 with high precision.

[0051] Next, in S1005, the bonding operation between the die 51 and the substrate 6 is performed. With reference to FIG. 5, the details of the bonding operation will be described.

[0052] In S3001, the control unit 441 controls the drive mechanism 450, which is a relative drive mechanism, to perform an approaching operation of bringing the bonding head 423 and the substrate stage 43 closer to each other so that the die 51 and the substrate 6 are in contact with each other.

[0053] In S3002, in order to eliminate the deformation of the bonding head 423 due to the suction and holding of the die 51 after the die 51 contacts the substrate 6, the suction force of the die by the suction mechanism 424 is set to zero. That is, the suction and holding of the die by the suction mechanism 424 is released once.

[0054] In S3003, the control unit 441 sets the suction force (holding force) of the suction mechanism 424 when the die 51 is re-held in the next S3004. The set holding force is greater than zero and less than a value such that the die can be separated from the normally bonded die and substrate. Specifically, a holding force is set such that a die normally bonded to the substrate by the approaching operation cannot be separated from the substrate, and a die not normally bonded to the substrate by the approaching operation can be separated from the substrate and held.

[0055] In S3004, the control unit 441 causes the suction mechanism 424 to suck the die 51 with the suction force set in S3003, thereby re-holding the die 51 by the bonding head 423. Then, in S3005, the control unit 441 controls the drive mechanism 450, which is a relative drive mechanism, to perform a separation operation of moving the bonding head 423 and the substrate stage 43 away from each other. Since the die 51 is held by the bonding head 423 in S3004, the separation operation is performed while applying a suction force (holding force) to the die 51. When the die 51 and the substrate 6 are normally bonded, the die 51 will not be separated from the substrate 6 with the set holding force. In this case, the die 51 is separated from the bonding head 423 as usual. However, since the set value of the holding force is greater than zero, if the die 51 is detached from the substrate 6 due to a bonding defect, the bonding head 423 can hold the die 51. This can prevent the displacement and dropping of the die in case of a bonding defect.

[0056] As described above, the bonding operation in S1005 was performed. Referring to FIG. 4 again, in S1006, the control unit 441 checks whether the bonding operation has been performed for all the dies to be bonded to the substrate 6. Usually, several tens to several hundreds of semiconductor devices are formed on one substrate, and since dies are bonded to each of them, the die bonding is repeated multiple times. If the bonding operation has not been performed for all the dies, the process returns to S2002.

[0057] Here, it is assumed that the determination process in S1006 is performed after the bonding operation in S1005. However, the determination process in S1006 may be performed in advance (for example, at a timing before S2002), and the die pickup operation in S2002 may be performed in parallel between the die alignment in S1003 and the bonding operation in S1005. Also, when multiple types of dies are bonded to one semiconductor device, after the bonding of one type of die is completed for all the semiconductor devices in one substrate, the bonding of the next type of die is started. In this case, in S2002, the next type of die is picked up. At this time, necessary processes such as the carrying-in operation of the dicing frame on which the next type of die is mounted are performed.

[0058] When the bonding operation is completed for all the dies, in S1007, the control unit 441 controls a substrate transfer device (not shown) to carry out the substrate 6 from the bonding device. The carried-out substrate may be returned to the original container such as a FOUP or to another container. Generally, since the thickness of the substrate has changed, it is necessary to widen the gap between the substrates compared to the substrate before bonding, so it is returned to another container.

[0059] The bonding flow for one substrate has been described above, and this operation is repeated for each of the required number of substrates.

[0060] Note that since the number of dies on the dicing frame and the number of semiconductor devices on the substrate to which the dies are bonded are generally different, the loading of the substrate and the loading of the dicing frame are not synchronized. During the bonding of one substrate, if the dies on the dicing frame are used up, the next dicing frame is loaded. If there are still dies remaining on the dicing frame even after the bonding of one substrate is completed, they are used for the bonding of the next substrate.

[0061] According to the above processing, even when there is a bonding defect between the die and the substrate, it is possible to suppress the displacement and dropping of the die.

[0062] <Second Embodiment> The relative drive mechanism (for example, drive mechanism 450) may include one or more actuators. When a voice coil motor (VCM) is used as each actuator, the command value for driving the VCM may be a current value. The control unit 441 determines the target drive amount of each actuator and gives the current value as the command value for realizing the target drive amount to each actuator. Each actuator is driven by a force corresponding to the given current value. Since an error occurs between the target drive amount and the actual drive amount, feedback control is performed to reduce this error. The control unit 441 adjusts the current value of the actuator based on the difference between the target drive amount and the actual drive amount. For example, when the drive amount measured using the interferometer is smaller than the target drive amount, the control unit 441 increases the current value to increase the drive amount. Conversely, when the measured drive amount is larger than the target drive amount, the control unit 441 decreases the current value to decrease the drive amount. By performing such feedback control, the drive amount is made closer to the target drive amount.

[0063] In the second embodiment, the suction force (holding force) by the bonding head 423 in the separation operation is set based on the current value which is the command value for the actuator of the relative drive mechanism.

[0064] As described above, in S3005, a separation operation is performed to move the bonding head 423 away from the substrate stage 43. With reference to FIG. 6, the separation operation of S3005 in the second embodiment will be described in detail.

[0065] In S6001, for example, the separation operation is performed by lowering the substrate chuck 433 by the drive mechanism 450. As described above, since this separation operation is performed while applying an attractive force (holding force) by the bonding head 423 to the die 51, resistance is generated against the downward drive of the substrate chuck 433. It is necessary to increase the driving force of the substrate chuck 433 to counteract the resistance, and thus a large amount of current is required.

[0066] In S6002, the control unit 441 monitors (acquires) its current value during the separation operation. In S6003, the control unit 441 determines whether the acquired current value exceeds a predetermined threshold value. If the acquired current value exceeds the threshold value, it is determined that the die 51 is normally bonded to the substrate 6. In this case, the process proceeds to S6004, and the control unit 441 reduces (for example, sets to zero) the suction force (holding force) of the die 51 by the bonding head 423 (suction mechanism 424). That is, when the bonding is normal, the bonding head 423 releases the die 51, and the operation proceeds to the next operation with the die 51 bonded to the substrate 6. On the other hand, if the current value does not exceed the threshold value even after a predetermined time has elapsed since the start of the separation operation, it indicates that there is no resistance to the downward drive of the substrate chuck 433. In this case, it is determined that the die 51 is not normally bonded to the substrate 6. For example, it is assumed that the die 51 has been peeled off from the substrate 6. When the bonding between the die 51 and the substrate 6 is defective, the die 51 and the substrate 6 separate from each other during the downward movement of the substrate chuck 433. However, since the suction force is set for the bonding head 423, the bonding head 423 can hold the die 51 and prevent the die 51 from shifting or falling. Note that the threshold value determination of the current value in S6003 may be performed by a suction force determination unit (not shown). If it is determined in S6003 that the current value does not exceed the threshold value, the process proceeds to S6005, and the control unit 441 outputs an error regarding the bonding defect.

[0067] The threshold value of the current value can be determined, for example, from the results of the die - substrate bonding test. Alternatively, during the operation of the bonding apparatus, the suction force (holding force) by the bonding head 423 and the history (log) of the current value output by the control unit 441 as a command value are recorded, and the threshold value may be determined based on the record when the die and the substrate are detached during the separation operation due to a bonding defect. Alternatively, the threshold value may be determined as follows. First, a minimum suction force (holding force) (for example, - 10 kPa) predetermined as being capable of holding the die 51 by the bonding head 423 is set. Next, in that state, as a separation operation, the substrate chuck 433 is driven downward. Then, the current value (command value) at the time when the bonding head 423 and the die 51 are separated is acquired. The control unit 441 determines this acquired current value as the threshold value.

[0068] Next, the separation operation when the relative drive mechanism is a drive mechanism that Z - drives the bonding head 423 will be described. The drive mechanism that Z - drives the bonding head 423 may also include, for example, a voice coil motor (VCM). The magnitude of the current supplied to the VCM is correlated with the driving force of the bonding head 423, and the driving force can be detected based on the magnitude of the current.

[0069] During the separation operation, since the bonding head 423 is sucking the die 51 bonded to the substrate 6, resistance is generated against the upward driving of the bonding head 423. In order to counteract that resistance, it is necessary to increase the driving force of the bonding head 423, and thus a large amount of current is required.

[0070] In S6002, the control unit 441 acquires the current value. In S6003, the control unit 441 determines whether the acquired current value exceeds a predetermined threshold value. If the acquired current value exceeds the threshold value, it is determined that the die 51 is normally bonded to the substrate 6. In this case, the process proceeds to S6004, and the control unit 441 sets the suction force of the die 51 by the bonding head 423 (suction mechanism 424) to zero. That is, when the bonding is normal, the bonding head 423 releases the die 51, and the operation proceeds to the next operation with the die 51 bonded to the substrate 6. On the other hand, if the current value does not exceed the threshold value, it indicates that there is no resistance to the upward drive of the bonding head 423. In this case, it is determined that the die 51 is not normally bonded to the substrate 6. When the bonding between the die 51 and the substrate 6 is defective, the die 51 and the substrate 6 separate during the upward movement of the bonding head 423. However, since the suction force is set on the bonding head 423, the bonding head 423 can hold the die 51 and prevent the die 51 from shifting or falling. In S6003, when it is determined that the current value does not exceed the threshold value, the process proceeds to S6005, and the control unit 441 outputs an error regarding the bonding defect.

[0071] According to the present embodiment, even when there is a bonding defect between the die and the substrate, it is possible to prevent the die from shifting or falling.

[0072] <Third Embodiment> In the second embodiment, the suction force (holding force) in the separation operation is set based on the current value, which is the command value for the actuator of the relative drive mechanism. In the third embodiment, the suction force (holding force) in the separation operation is set based on the suction air flow rate in the bonding head 423 (suction mechanism 424).

[0073] As described above, in S3005, a separation operation is performed to move the bonding head 423 away from the substrate stage 43. For example, the separation operation is performed by lowering the substrate chuck 433 by the drive mechanism 450. When the die 51 is normally bonded to the substrate 6, the die 51 is detached from the bonding head 423 by the lowering of the substrate chuck 433. When the die 51 is detached from the bonding head 423, the suction air leaks, and the suction air flow rate in the bonding head 423 (suction mechanism 424) changes.

[0074] The control unit 441 monitors (acquires) the suction air flow rate in the bonding head 423 (suction mechanism 424), and determines whether the acquired suction air flow rate exceeds a predetermined threshold value. When the acquired suction air flow rate exceeds the threshold value, it is determined that the die 51 is normally bonded to the substrate 6. In this case, the control unit 441 reduces (for example, sets to zero) the holding force for sucking the die 51 by the bonding head 423 (suction mechanism 424). That is, when the bonding is normal, the bonding head 423 releases the die 51, and the operation proceeds to the next operation with the die 51 bonded to the substrate 6. On the other hand, when the suction air flow rate does not exceed the threshold value, it is assumed that the die 51 and the substrate 6 are separated during the lowering of the substrate chuck 433. However, in that case, since a suction force is set in the bonding head 423, the bonding head 423 can hold the die 51 and prevent the die 51 from shifting or falling. Note that the threshold determination of the air flow rate may be performed by a flow rate determination unit (not shown).

[0075] Next, the separation operation in the case where the relative drive mechanism is a drive mechanism that Z-drives the bonding head 423 will be described. In this case, during the separation operation, the bonding head 423 is driven to rise. At this time, if the die 51 and the substrate 6 are bonded, the die 51 is detached from the bonding head 423 by the rising of the bonding head 423. When the die 51 is detached from the bonding head 423, the suction air leaks, and the suction air flow rate changes.

[0076] The control unit 441 monitors (acquires) the suction air flow rate and determines whether the acquired suction air flow rate exceeds a predetermined threshold value. If the acquired suction air flow rate exceeds the threshold value, it is determined that the die 51 is normally bonded to the substrate 6. In this case, the control unit 441 sets the suction force of the die 51 by the bonding head 423 (suction mechanism 424) to zero. That is, when the bonding is normal, the bonding head 423 releases the die 51 and proceeds to the next operation in the state where the die 51 is bonded to the substrate 6. On the other hand, if the suction air flow rate does not exceed the threshold value, it is assumed that the die 51 and the substrate 6 have separated during the upward movement of the bonding head 423. However, in that case, since the suction force is set on the bonding head 423, the bonding head 423 can hold the die 51 and prevent the die 51 from shifting or falling. If the suction air flow rate does not exceed the threshold value even after a predetermined time has elapsed since the start of the separation operation, the control unit 441 outputs an error related to poor bonding, for example.

[0077] According to the present embodiment, even when there is a poor bond between the die and the substrate, it is possible to prevent the die from shifting or falling.

[0078] <Embodiment of an article manufacturing method> A method for manufacturing an article (such as a semiconductor IC element, a liquid crystal display element, MEMS, etc.) using the above-described bonding apparatus will be described. The article manufacturing method according to the embodiment of the present disclosure is suitable for manufacturing articles such as microdevices such as semiconductor devices and elements having a fine structure. The article manufacturing method of the present embodiment includes a bonding step of bonding a first object to a second object using the above-described bonding apparatus, a processing step of processing the second object to which the first object has been bonded by the bonding step, and a manufacturing step of manufacturing an article from the second object processed in the processing step. Further, the manufacturing method includes other well-known steps (such as probing, dicing, bonding, packaging, etc.). The article manufacturing method of the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

[0079] The disclosure of this specification includes at least the following technical ideas. (Item 1) A bonding device for bonding a first object and a second object, a first holding part that sucks and holds the first object, a second holding part that holds the second object, a drive mechanism that performs an approaching operation of bringing the first holding part and the second holding part closer to each other so that the first object and the second object come into contact, and after the approaching operation, a separating operation of moving the first holding part and the second holding part away from each other, a control part that controls the operation of the drive mechanism and the holding force of the first object by the first holding part, and having, the control part causes the drive mechanism to perform the separating operation while applying a holding force to the first object by the first holding part. The bonding device is characterized by this. (Item 2) The holding force is a holding force that cannot pull the first object normally bonded to the second object by the approaching operation away from the second object, and can pull and hold the first object not normally bonded to the second object by the approaching operation away from the second object. The bonding device according to Item 1 is characterized by this. (Item 3) After the first object and the second object come into contact by the approaching operation, the control part releases the suction holding of the first object by the first holding part, and before the separating operation, causes the first holding part to suck and hold the first object again. The bonding device according to Item 1 is characterized by this. (Item 4) The drive mechanism includes an actuator that drives based on a given command value, the control part performs feedback control to adjust the command value given to the actuator based on the difference between the target drive amount and the actual drive amount of the actuator, when the command value exceeds a predetermined threshold during the separating operation, the control part reduces the holding force, The bonding device according to any one of Items 1 to 3 is characterized by this. (Item 5) If the command value does not exceed the threshold value even after a predetermined time has elapsed since the start of the separation operation, the control unit outputs an error related to a poor joint, and the bonding apparatus according to item 4, wherein the bonding apparatus is characterized in that. (Item 6) The bonding apparatus further includes a storage unit that stores the history of the holding force and the command value during the operation of the bonding apparatus. The control unit determines the threshold value based on the history when the first object and the second object are detached during the separation operation due to a poor joint. The bonding apparatus according to item 4 or 5, characterized in that. (Item 7) The control unit Performs the separation operation by setting a minimum holding force predetermined as a value that allows the first holding unit to hold the first object, Obtains the command value at the time when the first object leaves the first holding unit, Determines the obtained command value as the threshold value. The bonding apparatus according to item 4 or 5, characterized in that. (Item 8) The control unit monitors the suction air flow rate in the first holding unit during the separation operation, and reduces the holding force when the suction air flow rate exceeds a predetermined threshold value. The bonding apparatus according to any one of items 1 to 3, characterized in that. (Item 9) If the suction air flow rate does not exceed the threshold value even after a predetermined time has elapsed since the start of the separation operation, the control unit outputs an error related to a poor joint. The bonding apparatus according to item 8, characterized in that. (Item 10) A step of bonding a first object to a second object using the bonding apparatus according to item 1, A step of processing the second object to which the first object is bonded, And manufacturing an article from the processed substrate, and an article manufacturing method characterized in that.

[0080] The invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the claims are appended to disclose the scope of the invention.

Explanation of Signs

[0081] 3: Pickup unit, 4: Bonding unit, 6: Substrate, 31: Pickup head, 32: Release head, 43: Substrate stage, 51: Die, 421: Substrate observation camera, 422: Interferometer, 423: Bonding head, 424: Adsorption mechanism, 431: Die observation camera

Claims

1. A bonding device for bonding a first object and a second object, comprising: a first holding part that sucks and holds the first object; a second holding part that holds the second object; a drive mechanism that performs an approaching operation of bringing the first holding part and the second holding part closer to each other so that the first object and the second object come into contact with each other, and a separating operation of moving the first holding part and the second holding part away from each other after the approaching operation; a control part that controls the operation of the drive mechanism and the holding force of the first object by the first holding part; The control part causes the drive mechanism to perform the separating operation while applying a holding force to the first object by the first holding part. A bonding device characterized by this.

2. The holding force is a holding force that cannot pull the first object normally bonded to the second object away from the second object by the approaching operation, and can pull away and hold the first object that was not normally bonded to the second object by the approaching operation from the second object. The bonding device according to claim 1, characterized by this.

3. After the first object and the second object come into contact with each other by the approaching operation, the control part releases the suction holding of the first object by the first holding part, and before the separating operation, causes the first holding part to suck and hold the first object again. The bonding device according to claim 1, characterized by this.

4. The drive mechanism includes an actuator that drives based on a given command value. The control part performs feedback control to adjust the command value given to the actuator based on the difference between the target drive amount and the actual drive amount of the actuator. When the command value exceeds a predetermined threshold value during the separating operation, the control part reduces the holding force. The bonding device according to claim 1, characterized by this.

5. When the command value does not exceed the threshold value even after a predetermined time has elapsed since the start of the separating operation, the control part outputs an error related to a bonding failure. The bonding device according to claim 4, characterized by this.

6. The bonding device further includes a storage part that stores the history of the holding force and the command value during the operation of the bonding device. The control part determines the threshold value based on the history when the first object and the second object become detached during the separating operation due to a bonding failure. The bonding device according to claim 4, characterized by this.

7. The control part ​ ​ ​ ​ ​ ​ The separation operation is performed by setting a minimum holding force predetermined such that the first holding unit can hold the first object. The command value at the time when the first object separates from the first holding unit is acquired. The acquired command value is determined as the threshold value. The bonding device according to claim 4, characterized in that.

8. The control unit monitors the suction air flow rate in the first holding unit during the separation operation, and reduces the holding force when the suction air flow rate exceeds a predetermined threshold value. The bonding device according to claim 1, characterized in that.

9. When the suction air flow rate does not exceed the threshold value even after a predetermined time has elapsed since the start of the separation operation, the control unit outputs an error regarding a bonding defect. The bonding device according to claim 8, characterized in that.

10. A step of bonding a first object to a second object using the bonding device according to any one of claims 1 to 9; A step of processing the second object to which the first object is bonded; An article manufacturing method, comprising manufacturing an article from the processed substrate, characterized in that.

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