Hybrid bonding apparatus and hybrid bonding method based on visual alignment

Abstract

The application discloses a kind of hybrid bonding equipment and hybrid bonding method based on visual alignment, belong to bonding processing equipment field, it includes bonding assembly, first displacement mechanism, second displacement mechanism, first vision component, optical calibration component, second vision component and bearing table, through the mutual cooperation of two vision components and two displacement mechanisms, and the corresponding setting of optical calibration component, and then the position coordinates of calibration point, chip to be bonded and mark point on target chip can be accurately obtained, so that the compensation position information between two chips is accurately obtained, visual alignment before hybrid bonding of two chips is realized.The hybrid bonding equipment in the application has compact structure, is convenient to use, can accurately complete the bonding of chip to be bonded and target chip on wafer, and accurately realizes the visual alignment between chip to be bonded and target chip before hybrid bonding, effectively guarantees the alignment accuracy when chip hybrid bonding, reduces the error in bonding process, and improves the quality of chip product.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of bonding processing equipment, and particularly relates to a hybrid bonding device based on visual alignment and a hybrid bonding method. BACKGROUND

[0002] The hybrid bonding technology is a new type of semiconductor packaging technology, which can integrate homogeneous and heterogeneous materials and realize vertical stacking to improve the performance of chips. Compared with the traditional thermal compression bonding technology, the hybrid bonding technology can realize higher density interconnection without solder bumps and reduce chip power consumption.

[0003] Generally, the hybrid bonding process can be divided into three process stages of surface treatment, alignment bonding and post-treatment. Among them, the surface treatment process is to clean and activate the surfaces of chips and wafers by plasma or acid-base to enhance adhesion. The alignment bonding is to bond directly through van der Waals force, molecular and atomic force under the action of a certain pressure after the high-precision alignment of the chip and the wafer is completed to ensure one-to-one correspondence of the pads. The post-treatment process is to strengthen the bonding by annealing, and the annealing temperature is usually 200-300℃. In the whole process, the alignment accuracy is a key indicator affecting the electrical connection and reliability of the chip. Once the alignment accuracy is problematic, it will greatly affect the yield and cause huge losses. Therefore, how to accurately and effectively realize the alignment operation in the bonding process has become the focus of researchers and the first problem to be solved when improving the hybrid bonding processing efficiency and yield. SUMMARY

[0004] In view of one or more of the above defects or improvement needs of the prior art, the present application provides a hybrid bonding device based on visual alignment and a hybrid bonding method, which can accurately realize visual alignment in the hybrid bonding operation process, ensure the alignment accuracy of two objects before hybrid bonding, and improve the quality of hybrid bonding.

[0005] To achieve the above-mentioned purpose, in one aspect of the present application, a hybrid bonding device based on visual alignment is provided, which comprises a bonding assembly, a first displacement mechanism, a second displacement mechanism, a first visual assembly, an optical calibration assembly, a second visual assembly and a carrying table.

[0006] The carrying table is used for carrying a target chip, and is spaced apart from the second visual assembly in a first direction.

[0007] The bonding assembly comprises a bonding head connected with a pressure motor, which is used for taking a chip to be bonded and completing hybrid bonding of the chip to be bonded and the target chip.

[0008] The first displacement mechanism comprises a horizontal displacement assembly, the second displacement mechanism comprises a vertical lifting assembly and a plane adjustment assembly; the first visual assembly and the vertical lifting assembly are respectively assembled with the horizontal displacement assembly, so that the horizontal displacement assembly can drive the bonding assembly and the first visual assembly to synchronously displace in a first direction; the bonding assembly is assembled with the vertical lifting assembly through the plane adjustment assembly, the vertical lifting assembly can be used for lifting adjustment of the bonding assembly, and the plane adjustment assembly can be used for XYθ adjustment of the bonding assembly relative to the first visual assembly in a plane;

[0009] The first visual assembly is arranged on one side of the bonding assembly, and comprises a camera module and a semi-transmissive semi-reflective mirror and a reflective mirror arranged in sequence on a light path of the camera module, so that a shooting light path of the camera module can obtain first detection light and second detection light which are parallel to each other and vertically downward after passing through the two mirrors; the second visual assembly comprises a camera module, and is used for generating third detection light which is vertically upward;

[0010] The optical calibration assembly is arranged on a side of the bonding assembly close to the first visual assembly, and comprises a black film layer and a light transmission layer arranged in sequence in a first direction, and a calibration point is arranged at a bottom of the light transmission layer; position information of the calibration point and first mark points on the chip to be bonded is respectively acquired by the second visual assembly, position information of the calibration point and second mark points on a target chip is respectively acquired by the first visual assembly, compensation position information between the first mark points and the second mark points is acquired by coordinate conversion, and finally the alignment of the chip to be bonded and the target chip is adjusted according to the compensation position information by the plane adjustment assembly, so that visual alignment before hybrid bonding is completed.

[0011] As a further improvement of the present application, the bottom of the optical calibration assembly protrudes from the bottom of the bonding head, and the protruding distance of the optical calibration assembly is equal to the thickness of the chip to be bonded, so that the first mark points and the calibration point are located in the same horizontal plane.

[0012] As a further improvement of the present application, the bottom of the optical calibration assembly is flush with the bottom of the bonding head, and the depth of field range of the camera module in the second visual assembly is not less than the thickness of the chip to be bonded.

[0013] As a further improvement of the present application, the thickness of the black film layer is equal to the thickness of the light transmission layer.

[0014] And / or

[0015] The optical calibration assembly is movably connected with the sidewall surface of the bonding head through a displacement adjusting mechanism, and the displacement adjusting mechanism is used for adjusting the vertical position of the optical calibration assembly relative to the bonding head.

[0016] and / or

[0017] The thickness of the optical calibration assembly in the first direction is 0.5-3 times the first visual assembly lens barrel opening width.

[0018] As a further improvement of the present application, the optical calibration assembly is flush with the two side end surfaces of the bonding head at its two ends in the second direction, and the second direction is a horizontal direction perpendicular to the first direction.

[0019] As a further improvement of the present application, the first visual assembly and the second visual assembly are both two visual assemblies arranged in the second direction; and the calibration points are two calibration points arranged in the second direction.

[0020] As a further improvement of the present application, the bonding head is a suction disc with negative pressure adsorption capacity, and a plurality of adsorption holes are arranged on the bottom surface of the suction disc.

[0021] In another aspect of the present application, a hybrid bonding method based on visual alignment is provided, which uses the hybrid bonding device based on visual alignment to complete the bonding between the chip to be bonded and the target chip, and includes the following processes:

[0022] (1) Control the bonding head to take the chip to be bonded, and load the target chip onto the support table, so that the first mark point on the chip to be bonded faces downward, and the second mark point on the target chip faces upward;

[0023] (2) Control the first displacement mechanism to work, and drive the bonding assembly and the first visual assembly to move synchronously, so that the bonding assembly moves to the upper side of the second visual assembly;

[0024] (3) Control the second visual assembly to work, and obtain the position coordinates of the calibration points and the first mark point in the second coordinate system by the second visual assembly respectively;

[0025] (4) Control the first displacement mechanism to drive the first visual assembly and the bonding assembly to move synchronously to the upper side of the target chip; control the second displacement mechanism to drive the bonding assembly to translate relative to the first visual assembly, and calibrate the black film layer to the light path of the mirror, and calibrate the second mark point on the target chip to the light path of the semi-transmissive semi-reflective mirror;

[0026] (5) Control the first visual assembly to work, and obtain the position coordinates of the second mark point in the first coordinate system;

[0027] (6) controlling the second displacement mechanism to continue driving the bonding assembly to translate relative to the first vision assembly, calibrating the black film layer to the light path of the half-transmissive half-reflective mirror, and calibrating the calibration point to the light path of the mirror; continuing to control the first vision assembly to work, and acquiring the position coordinates of the calibration point in the first coordinate system;

[0028] (7) performing coordinate conversion between the second coordinate system and the first coordinate system, acquiring the compensation position difference between the first mark point and the second mark point, and controlling the second displacement mechanism to perform compensation movement according to the compensation position difference, so that the to-be-bonded chip and the target chip are vertically aligned;

[0029] (8) controlling the pressure motor in the bonding assembly to work, and pressing down the bonding head, so that the to-be-bonded chip and the aligned target chip are tightly attached, until the bonding process is completed.

[0030] As a further improvement of the present application, in process (1), after the bonding head adsorbs the to-be-bonded chip, the position of the optical calibration assembly is calibrated as follows: the black film layer is aligned with the second detection light emitted by the second mirror, and the first detection light emitted by the half-transmissive half-reflective mirror passes through the optical calibration assembly and is emitted downward.

[0031] and / or

[0032] In process (1), the bottom of the optical calibration assembly is flush with the bottom of the to-be-bonded chip, and the vertical distance between the calibration point and the target chip is calibrated to be equal to the distance between the two detection lights in the first vision assembly.

[0033] As a further improvement of the present application, in process (7), the coordinate conversion between the two coordinate systems is completed through the following conversion matrix formula:

[0034]

[0035] In the formula, X and Y describe the origin of the second coordinate system O name2 the position coordinates in the first coordinate system; is defined as the rotation matrix of the second coordinate system relative to the first coordinate system, and is used to represent the rotation angles of the X-axis and the Y-axis; R 11 , R 12 , R 21 , R 22 is an unknown quantity, which is solved by the coordinates of the calibration vector in the two coordinate systems.

[0036] The above improvement technical features can be combined with each other as long as they do not conflict with each other.

[0037] Overall, compared with the prior art, the above technical solutions conceived by the present application have the beneficial effects including:

[0038] (1) The mixed bonding device based on visual alignment of the present application comprises a bonding assembly, a first displacement mechanism, a second displacement mechanism, a first visual assembly, an optical calibration assembly, a second visual assembly and a carrying table. Through the cooperation of the two visual assemblies and the two displacement mechanisms, and the corresponding arrangement of the optical calibration assembly, the position coordinates of the calibration points, the to-be-bonded chip and the mark points on the target chip can be accurately obtained, so that the compensation position information between the two chips is accurately obtained, and the accurate alignment before mixed bonding of the two chips is realized, the alignment accuracy before chip bonding is ensured, the low yield caused by equipment control errors is avoided, and the mixed bonding cost of the chip is reduced.

[0039] (2) The mixed bonding device based on visual alignment of the present application, by preferably arranging the optical calibration assembly and the relative position between the optical calibration assembly and the first visual assembly, the accuracy of the position acquisition of the calibration points and the second mark points based on the first visual assembly, and the position acquisition of the calibration points and the first mark points based on the second visual assembly is ensured, the alignment error caused by the focusing difference of the camera is avoided, and the accuracy and reliability of the visual alignment are further improved.

[0040] (3) The mixed bonding device based on visual alignment of the present application, by preferably arranging two sets of first visual assemblies, two sets of second visual assemblies, and arranging two calibration points on the optical calibration assembly, the accuracy of the visual alignment of the to-be-bonded chip and the target chip is further improved, and the bonding quality of the chip is improved.

[0041] (4) The mixed bonding method based on visual alignment of the present application is completed based on the mixed bonding device arranged in combination, the steps are simple, the control is convenient, the accurate alignment of the to-be-bonded chip and the target chip before bonding can be realized through the acquisition of the corresponding positions of the calibration points and the two mark points and the conversion of the coordinates of each point, the bonding error caused by the inaccurate alignment of the two chips is avoided, the quality of the chip bonding is improved, and the scrap rate in the chip bonding process is reduced.

[0042] (5) The mixed bonding device based on visual alignment in the present application has a compact structure and is convenient to use, can accurately complete the bonding of the to-be-bonded chip and the target chip on the wafer, accurately realize the visual alignment between the to-be-bonded chip and the target chip before mixed bonding, effectively ensure the alignment accuracy during the mixed bonding of the chip, reduce the equipment error during the bonding process, improve the quality and yield of the chip product, and has good economic value. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0044] Figure 1 is a structural schematic diagram of a hybrid bonding device based on visual alignment in an embodiment of the present application;

[0045] Figure 2 is a schematic diagram when positioning is performed by using a second visual assembly in an embodiment of the present application;

[0046] Figure 3 is a schematic diagram when first positioning is performed by using a first visual assembly in an embodiment of the present application;

[0047] Figure 4 is a schematic diagram when second positioning is performed by using the first visual assembly in an embodiment of the present application;

[0048] Figure 5 is a structural side view of a hybrid bonding device based on visual alignment in an embodiment of the present application;

[0049] In all the drawings, the same reference signs represent the same technical features, specifically:

[0050] 1, bonding assembly; 2, first displacement mechanism; 3, second displacement mechanism; 4, first visual assembly; 5, optical calibration assembly; 6, second visual assembly; 7, chip to be bonded; 8, target chip; 9, wafer; 10, bearing table;

[0051] 101, bonding head; 102, pressure sensor; 103, pressure motor;

[0052] 201, translation motor; 202, translation guide rail; 203, fixed plate;

[0053] 301, lifting motor; 302, lifting guide rail;

[0054] 401, camera module; 402, first mirror; 403, semi-transmissive semi-reflective mirror; 404, second mirror;

[0055] 501, black film layer; 502, light-transmissive layer; 503, calibration point;

[0056] 701, first mark point; 801, second mark point. DETAILED DESCRIPTION

[0057] In order to make the objects, technical solutions and advantages of the present application clearer, the following further describes the present application with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely intended to explain the present application and not to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0058] In the description of the present application, it should be understood that, unless specifically defined and limited otherwise, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are merely intended to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0059] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless specifically defined otherwise.

[0060] In the present application, unless specifically defined and limited otherwise, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless specifically defined otherwise. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0061] In the present application, unless specifically defined and limited otherwise, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0062] Embodiments:

[0063] Referring to Figures 1-5 The hybrid bonding device based on visual alignment in the preferred embodiment of the present application comprises a bonding assembly 1, a first visual assembly 4, an optical calibration assembly 5, a second visual assembly 6 and a carrier table 10.

[0064] The bonding assembly 1 is used for picking up the chip to be bonded 7 and performing the bonding process; and the carrier table 10 is used for carrying the target chip 8, specifically, for carrying a wafer 9 carrying a plurality of target chips 8.

[0065] Meanwhile, the optical calibration assembly 5 in the preferred embodiment is arranged on one side of the bonding assembly 1, and is used for cooperating with the first visual assembly 4 and the second visual assembly 6 to complete the visual alignment between the first mark point 701 on the chip to be bonded 7 and the second mark point 801 on the target chip 8, so as to ensure the accurate alignment between the chip to be bonded 7 and the target chip 8 in the subsequent hybrid bonding process of the bonding assembly 1, and avoid the existence of defective products due to the alignment error.

[0066] More specifically, the first visual assembly 4 in the preferred embodiment is arranged on one side of the bonding assembly 1, and the detection light output from the lens of the first visual assembly 4 is two parallel lights emitted downward, i.e., the negative direction of the Z axis as shown in Figure 1 .

[0067] Correspondingly, the second visual assembly 6 is arranged on one side of the carrier table 10 along the first direction, i.e., one side of the X axis direction as shown in Figure 1 , and the third detection light output from the lens of the second visual assembly 6 is upward, i.e., the positive direction of the Z axis as shown in Figure 1 .

[0068] Further, the optical calibration assembly 5 in the preferred embodiment comprises a black film layer 501 and a light transmission layer 502 arranged in the X axis direction, and a calibration point 503 is arranged at the bottom of the light transmission layer 502, so as to realize the visual alignment between the optical calibration assembly 5 and the two visual assemblies through the imaging of the calibration point 503 in the first visual assembly 4 and the second visual assembly 6.

[0069] In order to accurately realize the visual alignment process and the hybrid bonding process, the preferred embodiment is further provided with a first displacement mechanism 2 and a second displacement mechanism 3. Among them, the first displacement mechanism 2 is an X-axis direction displacement mechanism, which includes a horizontal displacement assembly for driving the bonding assembly 1 and the first visual assembly 4 to simultaneously perform horizontal displacement in the first direction, realizing the respective alignment of the bonding assembly 1 and the second visual assembly 6, the carrier table 10. At the same time, the second displacement mechanism is provided corresponding to the bonding assembly 1, including a vertical lifting assembly and a plane adjusting assembly, for driving the bonding assembly 1 to lift and adjust the XYθ plane relative to the first visual assembly 4, so as to ensure that the to-be-bonded chip 7 is accurately aligned with the target chip 8.

[0070] In actual setting, the bottom surface of the to-be-bonded chip 7 taken by the bonding assembly 1 and the top surface of the target chip 8 are respectively provided with mark points, i.e. the first mark point 701 and the second mark point 801. Then the position coordinates of the calibration point 503 and the first mark point 701 are obtained by the second visual assembly 6, and the position coordinates of the calibration point 503 and the second mark point 801 are obtained by the first visual assembly 4. By taking the position of the calibration point 503 as the conversion reference, the positions of the first mark point 701 and the second mark point 801 in the same three-dimensional coordinate system are converted, and finally the compensation position information between the first mark point 701 and the second mark point 801 is obtained, and the position of the to-be-bonded chip 7 is adjusted to be aligned with the corresponding target chip 8 before hybrid bonding.

[0071] Specifically, the bonding assembly 1 in the preferred embodiment includes a bonding head 101, the top of which is connected with the output shaft of a pressure motor 103, and a pressure sensor 102 is arranged corresponding to the connection of the two, so that the pressure of the bonding head 101 during the bonding operation can be accurately obtained through the detection of the pressure sensor 102.

[0072] More specifically, in order to accurately realize the taking of the to-be-bonded chip 7, the bonding head 101 is preferably arranged in the form of a suction disc with negative pressure adsorption capacity, and a plurality of adsorption holes are arranged on the bottom surface thereof at intervals.

[0073] Further, the first displacement mechanism 2 in the preferred embodiment includes a translation guide rail 202 arranged along the first direction, and a translation motor 201 and a fixed plate 203 are arranged corresponding to the translation guide rail 202. Among them, the translation motor 201 is assembled and connected with the translation guide rail 202, and can perform reciprocating displacement in the first direction relative to the translation guide rail 202 during work. At the same time, the fixed plate 203 is fixedly connected relative to the translation motor 201, and can follow the synchronous displacement of the translation motor 201 when the translation motor 201 performs translation.

[0074] Accordingly, in the preferred embodiment, the first visual component 4 is mounted on the fixed plate 203 , and the bonding component 1 is disposed on the fixed plate 203 via the second displacement mechanism 3 .

[0075] The second displacement mechanism 3 in the preferred embodiment includes a lifting guide rail 302 extending vertically and a lifting motor 301 assembled on the lifting guide rail 302. The vertical displacement of the bonding head 101 can be accurately achieved through the drive of the lifting motor 301 and the guidance of the lifting guide rail 302.

[0076] At the same time, the second displacement mechanism 3 also includes a plane adjustment component (not shown in the figure) arranged corresponding to the bonding component 1 and the first visual component 4, which is used to realize the first direction displacement of the bonding component 1 relative to the first visual component 4.

[0077] For example, in actual settings, the aforementioned plane adjustment component is preferably arranged between the lifting motor 301 and the pressure motor 103, and is further preferably an XYθ displacement adjustment module, which can perform displacement adjustment within the XY axis plane and θ angle adjustment around the plane Z axis as shown in the figure, thereby completing the application of compensation position information.

[0078] Through the combined arrangement of the first displacement mechanism 2 and the second displacement mechanism 3, the first visual component 4 can be synchronously displaced following the bonding component 1 during the visual alignment process, ensuring that the relative position between the first visual component 4 and the bonding head 101 can be maintained at a smaller distance, thereby reducing the displacement adjustment amount of the bonding component 1 relative to the first visual component 4 during the visual alignment process and the compensation position adjustment process.

[0079] Furthermore, in the preferred embodiment, the first visual component 4 includes a camera module 401 and a visual alignment light path corresponding thereto. The camera module 401 in the preferred embodiment includes a camera, a lens and a light source, and is capable of emitting detection light into the visual alignment light path. At the same time, a semi-transmissive and semi-reflective mirror 403 and a second reflector 404 are sequentially arranged in the visual alignment light path, and the two lenses are spaced apart in the first direction, so that the detection light emitted by the camera module 401 can obtain a beam of downward first detection light and a beam of transmitted light directed toward the second reflector 404 after passing through the semi-transmissive and semi-reflective mirror 403. After the transmitted light is reflected by the second reflector 404, a second detection light is obtained that is spaced a certain distance from the first detection light and is parallel to the first detection light.

[0080] In actual setting, the interval between the first detection light and the second detection light ( Figure 4 W3 in the figure corresponds to the size of the optical calibration component 5 in the first direction (the X-axis direction in the figure), ensuring that the two detection lights can be simultaneously irradiated onto the optical calibration component 5 under test requirements.

[0081] Meanwhile, it is further preferred in the preferred embodiment that a first mirror 402 is arranged between the camera module 401 and the half-transmissive half-reflective mirror 403, for reflecting the detection light beam from the camera module 401 to the half-transmissive half-reflective mirror 403, so as to facilitate the arrangement of the camera module 401.

[0082] In more detail, the second mirror 404 in the preferred embodiment is arranged at the side of the half-transmissive half-reflective mirror 403 close to the bonding assembly 1, i.e. the second detection light is located between the first detection light and the bonding head 101.

[0083] Further, the optical calibration assembly 5 in the preferred embodiment comprises a black film layer 501 and a light-transmissive layer 502 arranged in a stack in the first direction, and the center distance between the two layers is further preferably equal to the distance between the first detection light and the second detection light.

[0084] Meanwhile, a calibration point 503 is arranged on the bottom surface of the light-transmissive layer 502, so that the corresponding detection light beam (the second detection light in the preferred embodiment) can pass through the light-transmissive layer 502 and complete the shooting imaging of the calibration point 503, and further obtain the position information of the calibration point 503 in the corresponding coordinate system.

[0085] In more detail, the optical calibration assembly 5 in the preferred embodiment is arranged at the side of the bonding head 101 close to the first visual assembly 4, and the bottom of the optical calibration assembly 5 protrudes from the bottom surface of the bonding head 101, and the protruding distance is further preferably equal to the thickness of the chip 7 to be bonded, so that after the bonding head 101 completes the picking of the chip 7 to be bonded, the calibration point 503 and the first mark point 701 are located on the same horizontal plane.

[0086] Based on the above arrangement of the optical calibration assembly 5, it is also convenient for the second visual assembly 6 to quickly and accurately complete the positioning shooting of the calibration point 503 and the first mark point 701 when performing visual positioning.

[0087] For the second visual assembly 6 in the preferred embodiment, it is preferably a camera assembly, comprising a camera, a lens and a light source, and the arrangement form can be further preferably the same as the camera module 401.

[0088] Of course, according to the actual setting needs, the optical calibration assembly 5 can also be preferably arranged in a form that the bottom is flush with the bottom of the bonding head 101, and at this time, the second visual assembly 6 preferably selects a camera assembly with a depth of field range not less than the thickness of the chip 7 to be bonded. For this kind of mode, it is possible to reduce the installation difficulty of the optical calibration assembly 5 to a certain extent, and reduce the influence of the optical calibration assembly 5 on other chips except the target chip 8 during subsequent hybrid bonding.

[0089] Exemplarily, in a more specific preferred embodiment, the optical calibration assembly 5 is movably connected with the sidewall surface of the bonding head 101 through a displacement adjustment mechanism, and the vertical position of the optical calibration assembly 5 relative to the bonding head 101 can be adjusted as needed.

[0090] In actual alignment, after the pick-up of the chip 7 to be bonded is completed, the position of the bonding assembly 1 in the first direction is preferably adjusted to the following position:

[0091] The optical calibration assembly 5 does not block the first detection light reflected by the semi-transmissive semi-reflective mirror 403, and the second detection light output after being reflected by the second mirror 404 is directed to the black film layer 501.

[0092] At the same time, the vertical distance H1 between the chip 7 to be bonded and the target chip 8 is adjusted to be equal to the distance W3 between the semi-transmissive semi-reflective mirror 403 and the second mirror 404. In this way, the optical path of the first detection light for shooting the second mark point 801 and the optical path of the second detection light for shooting the calibration point 503 can be ensured to be equal.

[0093] By setting the optical calibration assembly 5 in a form that the bottom is flush with the chip 7 to be bonded, and setting the distance between the chip 7 to be bonded and the target chip 8 to be equal to the distance between the two detection light beams after being emitted by the first vision assembly 4, the alignment focal points of the detection light beams at the required shooting points are consistent, thereby reducing the visual precision error caused by inconsistent focal points.

[0094] More preferably, in actual setting, the thickness W2 of the optical calibration assembly 5 in the first direction is preferably 0.5-3 times the barrel opening width W1 of the first vision assembly 4.

[0095] Exemplarily, in the preferred embodiment, W1 is 1-10 mm, and W2 is 0.5-30 mm.

[0096] Further preferably, the thickness of the black film layer 501 and the light-transmitting layer 502 in the optical calibration assembly 5 is preferably equal, and the thickness of each is preferably 0.25-15 mm.

[0097] Exemplarily, in actual setting, the length dimension of the optical calibration assembly 5 in the second direction is preferably equal to the size of the bonding head 101 in the second direction, and the two ends of the optical calibration assembly 5 along the second direction are flush with the two end surfaces of the bonding head 101, as shown in FIG. 4. Figure 5 It should be noted that the above-mentioned second direction is a horizontal direction perpendicular to the first direction, i.e., the Y-axis direction as shown in FIG. 4. Figure 1

[0098] ​In actual operation, a first coordinate system {name1} is established based on the bonding assembly 1 and the first vision assembly 4 in the preferred embodiment, and a second coordinate system {name2} is established based on the second vision assembly 6.

[0099] Based on this, a matrix is set to convert the vector described in the second coordinate system {name2} to the description under the first coordinate system {name1}. In a two-dimensional coordinate system in a plane, The matrix is preferably 3x3.

[0100] The conversion matrix formula is as follows:

[0101]

[0102] In the formula, X and Y describe the origin of the {name2} coordinate system O name2 The position coordinates in the {name1} coordinate system; is defined as the rotation matrix of the {name2} coordinate system relative to the {name1} coordinate system, which is used to represent the rotation angle of the X axis and the Y axis, and describes the attitude of the {name2} coordinate system relative to the {name1} coordinate system; R 11 、 R 12 、 R 21 、 R 22 are unknown quantities, which can be solved by calibrating the vector P 1、 P 2 in the {name1} and {name2} coordinate systems.

[0103] Through the design of the above conversion matrix formula, after the position information of each point is acquired by the two vision assemblies, the conversion of the coordinate positions in the two coordinate systems can be accurately completed, and the compensation position information between the second mark point 801 and the first mark point 701 is accurately acquired, and the visual alignment of the chip to be bonded 7 relative to the target chip 8 is completed.

[0104] For example, if a vector P is known, the description in the second coordinate system {name2} is name2 P At the same time, the conversion matrix is known, then the vector P is described in the first coordinate system {name1}:

[0105] name1 P = name2 P

[0106] For the two visual components, it is possible to accurately complete the acquisition of the position coordinates of the calibration point 503 and the corresponding marking point in the two coordinate systems, and then obtain a vector based on the bright spot in each of the two coordinate systems; in the design based on the aforementioned transformation matrix formula, the position compensation information between the first marking point 701 and the second marking point 801 can be accurately obtained to complete the alignment between the chip to be bonded 7 and the target chip 8.

[0107] After alignment is completed, the bonding head 101 is controlled to press down. When the pressure reaches 1-5N, the vacuum is broken, and the two chips are tightly bonded together to complete the direct bonding process.

[0108] In a preferred embodiment, after the wafer 9 and the target chip 8 are loaded onto the carrier 10, the carrier 10 remains in a fixed position, and the relative position between the second vision component 6 and the carrier 10 remains fixed. However, in actual installation, a displacement mechanism may be preferably provided for the carrier 10 to adjust the position of the carrier 10 and the relative position between the carrier 10 and the second vision component 6 within the entire device.

[0109] In addition, it is also preferred to provide a displacement mechanism for the second visual component 6, which will not be described in detail here.

[0110] As another aspect of the present invention, based on the aforementioned hybrid bonding device, a hybrid bonding method based on vision alignment is further proposed, which preferably includes the following process:

[0111] (1) Control the bonding head 101 to absorb the chip 7 to be bonded so that the first marking point 701 on the chip 7 to be bonded faces downward; accordingly, load the wafer 9 with a plurality of target chips 8 onto the carrier 10;

[0112] When performing process (1), the optical calibration component 5 is preferably calibrated to the following position: the black film layer 501 is aligned with the second detection light emitted by the second reflector 404, and the first detection light emitted by the semi-transmissive semi-reflective mirror 403 passes over the optical calibration component 5 and is emitted downward;

[0113] At the same time, it is preferred to align the bottom of the optical calibration component 5 with the bottom of the chip to be bonded 7 , and calibrate the vertical distance between the calibration point 503 and the target chip 8 to be equal to the spacing between the two detection beams in the first visual component 4 .

[0114] (2) Control the first displacement mechanism 2 to drive the bonding component 1 to move above the second visual component 6, as shown in FIG. Figure 2 As shown in ; At this time, the first visual component 4 follows the synchronous movement of the bonding component 1;

[0115] (3) controlling the second visual component 6 to work, and acquiring the position coordinates of the calibration point 503 and the first mark point 701 in the second coordinate system by the second visual component 6 respectively;

[0116] (4) controlling the first displacement mechanism 2 to work, and driving the first visual component 4 to move above the target chip 8; at this time, the bonding component 1 moves synchronously with the first visual component 4;

[0117] (5) controlling the second displacement mechanism 3 to work, and driving the bonding component 1 to move relative to the first visual component 4, and calibrating the black film layer 501 to the light path of the second mirror 404, and calibrating the second mark point 801 on the target chip 8 to the light path of the semi-transmissive semi-reflective mirror 403, and controlling the first visual component 4 to work, and acquiring the position coordinates of the second mark point 801 in the first coordinate system;

[0118] The above alignment process (5) can be completed in process (1), or can be performed after process (4) is completed, which will not be repeated here.

[0119] (6) controlling the second displacement mechanism 3 to work, and continuing to drive the bonding component 1 to move relative to the first visual component 4 (i.e. moving along the negative direction of the X axis in the second coordinate system), and calibrating the black film layer 501 to the light path of the semi-transmissive semi-reflective mirror 403, and calibrating the calibration point 503 to the light path of the second mirror 404; thereafter, the camera module 401 continues to take pictures, and the position coordinates of the calibration point 503 in the first coordinate system are acquired; Figure 4

[0120] (7) performing coordinate conversion between the second coordinate system and the first coordinate system, and according to the position coordinates of the first mark point 701, the calibration point 503 and the second mark point 801, the compensation position difference between the first mark point 701 and the second mark point 801 is calculated, and the second displacement mechanism 3 is controlled to move according to the compensation position difference, so that the first mark point 701 moves to the top of the second mark point 801, and the alignment between the chip to be bonded 7 and the target chip 8 is completed;

[0121] In the preferred embodiment, the coordinate conversion between the two coordinate systems is completed by the aforementioned conversion matrix formula, which will not be repeated here.

[0122] (8) controlling the pressure motor 103 in the bonding component 1 to work, and pressing the bonding head 101 downward, so that the chip to be bonded 7 and the aligned target chip 8 are tightly attached, until the bonding process is completed.

[0123] ​In another specific preferred embodiment, the two calibration points 503 at the bottom of the light-transmitting layer 502 are arranged at two ends of the Y-axis direction, and the first mark points 701 on the chip 7 to be bonded and the second mark points 801 on the target chip 8 are also two in the Y-axis direction. Correspondingly, two first visual assemblies 4 (i.e. visual assembly 4a and visual assembly 4b in FIG. 1) are arranged in the Y-axis direction of the second displacement mechanism 3, and the second visual assembly 6 is also arranged in two sets in the Y-axis direction. Figure 5

[0124] At this time, in the above process (3), the position coordinates of the two calibration points 503 at the bottom of the light-transmitting layer 502 and the two first mark points 701 at one end of the chip 7 to be bonded close to the optical calibration assembly 5 in the second coordinate system are obtained by the two second visual assemblies 6 respectively.

[0125] Meanwhile, in the above processes (5) and (6), the position coordinates of the two second mark points 801 at one end of the target chip 8 in the X-axis direction and the two calibration points 503 at the bottom of the light-transmitting layer 502 in the first coordinate system are obtained by the two first visual assemblies 4 respectively.

[0126] Thereafter, in the above process (7), based on the plurality of position coordinates obtained in the first coordinate system and the second coordinate system, the compensation position difference between the two first mark points 701 and the two second mark points 801 is calculated, and then the position adjustment of the chip 7 to be bonded is completed according to the compensation position difference, so that the chip 7 to be bonded and the target chip 8 are accurately aligned in the Z-axis direction.

[0127] Finally, the hybrid bonding between the chip 7 to be bonded and the target chip 8 is completed through the lifting movement of the bonding assembly 1 in the Z-axis direction.

[0128] The hybrid bonding device based on visual alignment in the application has the advantages of compact structure, convenient use, accurate completion of the bonding between the chip to be bonded and the target chip on the wafer, accurate visual alignment between the chip to be bonded and the target chip before hybrid bonding, effective guarantee of the alignment accuracy during the hybrid bonding of the chip, reduction of the equipment error during the bonding process, improvement of the quality and yield of the chip product, and good economic value.

[0129] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the application, and is not intended to limit the application. Any modification, equivalent replacement and improvement made within the spirit and principle of the application shall be included in the protection scope of the application.​

Claims

1. A hybrid bonding device based on vision alignment, characterized in that: It includes a bonding component, a first displacement mechanism, a second displacement mechanism, a first vision component, an optical calibration component, a second vision component and a carrying platform; The carrying platform is used to carry the target chip, and is spaced apart from the second visual component in the first direction; The bonding assembly includes a bonding head connected to a pressure motor, which is used to take the chip to be bonded and complete the mixed bonding of the chip to be bonded and the target chip; The first displacement mechanism includes a horizontal displacement assembly, and the second displacement mechanism includes a vertical lifting assembly and a plane adjustment assembly; the first vision assembly and the vertical lifting assembly are respectively assembled and connected to the horizontal displacement assembly, so that the horizontal displacement assembly can drive the bonding assembly and the first vision assembly to synchronously displace in a first direction; the bonding assembly is assembled and connected to the vertical lifting assembly via the plane adjustment assembly, and the bonding assembly can be raised and lowered by the vertical lifting assembly, and the bonding assembly can be adjusted in an XYθ plane relative to the first vision assembly by the plane adjustment assembly; The first visual component is arranged on one side of the bonding component, and includes a camera module and a semi-transmissive and semi-reflective mirror and a reflective mirror arranged in sequence on the optical path of the camera module, so that the shooting optical path of the camera module can obtain a first detection light and a second detection light that are parallel to each other and vertically downward after passing through the two lenses; the second visual component includes a camera module for generating a third detection light that is vertically upward; The optical calibration component is arranged on a side of the bonding component close to the first visual component, and includes a black film layer and a light-transmitting layer arranged in sequence in a first direction, and a calibration point is arranged at the bottom of the light-transmitting layer; the position information of the calibration point and the first marking point on the chip to be bonded is respectively obtained through the second visual component, and the position information of the calibration point and the second marking point on the target chip is respectively obtained through the first visual component, and the compensation position information between the first marking point and the second marking point is obtained by coordinate transformation. Finally, the plane adjustment component adjusts the alignment of the chip to be bonded and the target chip according to the compensation position information to complete the visual alignment before hybrid bonding.

2. The hybrid bonding device based on vision alignment according to claim 1, characterized in that The bottom of the optical calibration component protrudes from the bottom of the bonding head, and the protruding distance of the optical calibration component is equal to the thickness of the chip to be bonded, so that the first marking point and the calibration point are located in the same horizontal plane.

3. The hybrid bonding device based on vision alignment according to claim 1, characterized in that The bottom of the optical calibration component is flush with the bottom of the bonding head, and the depth of field range of the camera module in the second visual component is not less than the thickness of the chip to be bonded.

4. The hybrid bonding device based on vision alignment according to any one of claims 1 to 3, characterized in that: The thickness of the black film layer is equal to that of the light-transmitting layer; and / or The optical calibration component is movably connected to the side wall surface of the bonding head via a displacement adjustment mechanism, and the displacement adjustment mechanism is used to adjust the vertical position of the optical calibration component relative to the bonding head; and / or The thickness of the optical calibration component in the first direction is 0.5 to 3 times the width of the opening of the first visual component lens barrel.

5. The hybrid bonding device based on vision alignment according to claim 4, characterized in that The optical calibration component has two ends aligned with both side end surfaces of the bonding head in a second direction, and the second direction is a horizontal direction perpendicular to the first direction.

6. The hybrid bonding device based on vision alignment according to claim 5, characterized in that The first visual component and the second visual component are both two spaced apart in the second direction; and the calibration points are two spaced apart in the second direction.

7. The hybrid bonding device based on vision alignment according to any one of claims 1 to 3, 5 and 6, characterized in that: The bonding head is a suction cup with negative pressure adsorption capability, and a plurality of adsorption holes are arranged at intervals on the bottom surface of the suction cup.

8. A hybrid bonding method based on vision alignment, which uses the hybrid bonding device based on vision alignment according to any one of claims 1 to 7 to complete the bonding between the chip to be bonded and the target chip, characterized in that: The process includes the following: (1) Controlling the bonding head to pick up the chip to be bonded, and loading the target chip onto the carrier, so that the first marking point on the chip to be bonded faces downward and the second marking point on the target chip faces upward; (2) Controlling the first displacement mechanism to drive the bonding component and the first vision component to move synchronously, so that the bonding component moves above the second vision component; (3) controlling the second visual component to obtain the position coordinates of the calibration point and the first marking point in the second coordinate system respectively; (4) Controlling the first displacement mechanism to drive the first vision component and the bonding component to move synchronously to the top of the target chip; controlling the second displacement mechanism to drive the bonding component to translate relative to the first vision component, and marking the black film layer on the optical path of the reflector, and marking the second marking point on the target chip on the optical path of the semi-transmissive semi-reflective mirror; (5) Control the first visual component to obtain the position coordinates of the second marking point in the first coordinate system; (6) Controlling the second displacement mechanism to continue to drive the bonding assembly to translate relative to the first vision assembly, calibrating the black film layer to the optical path of the semi-transmissive and semi-reflective mirror, and calibrating the calibration point to the optical path of the reflective mirror; continuing to control the operation of the first vision assembly to obtain the position coordinates of the calibration point in the first coordinate system; (7) performing coordinate conversion between the second coordinate system and the first coordinate system, obtaining a compensation position difference between the first marking point and the second marking point, and controlling the second displacement mechanism to perform a compensation movement according to the compensation position difference, so that the chip to be bonded is vertically aligned with the target chip; (8) Control the pressure motor in the bonding assembly to press the bonding head down so that the chip to be bonded fits tightly with the aligned target chip until the bonding process is completed.

9. The hybrid bonding method based on vision alignment according to claim 8, characterized in that: In process (1), after the bonding head absorbs the chip to be bonded, the position of the optical calibration component is calibrated so that the black film layer is aligned with the second detection light emitted by the second reflector, and the first detection light emitted by the semi-transmissive semi-reflective mirror passes over the optical calibration component and is emitted downward; and / or In process (1), the bottom of the optical calibration component is aligned with the bottom of the chip to be bonded, and the vertical distance between the calibration point and the target chip is calibrated to be equal to the spacing between the two detection lights in the first visual component.

10. The hybrid bonding method based on vision alignment according to claim 8 or 9, characterized in that: In process (7), the coordinate transformation between the two coordinate systems is completed by the following transformation matrix formula: Where X and Y describe the origin of the second coordinate system O name2 Position coordinates in the first coordinate system; Defined as the rotation matrix of the second coordinate system relative to the first coordinate system, used to represent the rotation angle of the X-axis and Y-axis; R 11 、 R 12 、 R 21 、 R 22 The unknown quantity is solved by calibrating the coordinates of the vector in the two coordinate systems.

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