Bonding device and bonding method

Abstract

The bonding device and bonding method of the present invention can suppress the continuous lateral shift of semiconductor chips in one direction during stacking bonding. The bonding device includes: a position detection unit (55) for detecting the position of the semiconductor chip and storing each detected position in a position database (56); a position correction unit (57) for outputting the corrected bonding position; and a bonding control unit (58) for bonding the semiconductor chip based on the corrected bonding position input from the position correction unit (57). The position correction unit (57) calculates the position shift amount and the cumulative position shift amount between the semiconductor chips of each layer. When the cumulative position shift amount is greater than a predetermined threshold value, the position of the semiconductor chip is corrected by only the cumulative position shift amount and output as the corrected bonding position. The bonding control unit (58) performs bonding of the semiconductor chip of the next layer at the corrected bonding position input from the position correction unit.

Description

Technical Field

[0001] The present invention relates to a structure of a bonding device for stacking and bonding semiconductor chips and a bonding method using the bonding device. Background Art

[0002] A stacked semiconductor device is used in which multiple semiconductor chips are stacked and bonded. When stacking and bonding semiconductor chips, a method of bonding the semiconductor chips using position detection marks provided on the surfaces of the semiconductor chips may be used. For example, a method may be used in which the position of the mark on the bonded semiconductor chip is detected and the bonding position is adjusted so that the position of the mark on the next semiconductor chip to be bonded matches the position of the mark on the previously bonded semiconductor chip (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 5243284 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] However, as described above, when the position of the mark of the semiconductor chip to be joined next is aligned with the position of the mark of the semiconductor chip to be joined previously, due to errors in the joining device, etc., there is a situation where the semiconductor chips are stacked and joined in a state of continuous lateral shift in one direction, resulting in the stacked semiconductor device becoming a tilted device.

[0008] Therefore, an object of the present invention is to suppress the continuous lateral shift of semiconductor chips in one direction during stack bonding.

[0009] Technical means to solve the problem

[0010] The bonding device of the present invention is a bonding device for stacking and bonding a plurality of semiconductor chips on a plurality of bonding areas of a base member, comprising: a position detection unit for detecting the positions of the bonding areas of the base member and the positions of the semiconductor chips of each layer stacked and bonded on the bonding areas of the base member, and storing the data of the detected positions in a position database for each bonding area of ​​the base member; a position correction unit for correcting the bonding position while referring to the position database and outputting the corrected bonding position; and a bonding control unit for bonding the semiconductor chips based on the corrected bonding position input from the position correction unit, wherein the position correction unit calculates the position of the bonding area of ​​the base member and the position of the semiconductor chips bonded thereto each time the semiconductor chips of each layer are bonded. The positional offset between the positions of the conductor chips or the positional offset between the position of the joined semiconductor chip and the position of the semiconductor chip joined directly above it is calculated, and each calculated positional offset is stored in a position database according to each joining area of ​​the base member, and the positional offset from the base member to the semiconductor chip of the joined layer when the semiconductor chips are stacked and joined is accumulated to calculate the cumulative positional offset. When the cumulative positional offset is greater than a specified threshold value, only the cumulative positional offset is corrected for each position of each semiconductor chip of the layer joined before detection by the position detection unit, and the position is output as a corrected joining position, and the joining control unit joins the semiconductor chip of the next layer at the corrected joining position input from the position correction unit.

[0011] As described above, during stacking and bonding, the positional offset of each layer is stored in a position database and the cumulative positional offset is calculated. When the cumulative positional offset is greater than a predetermined threshold, the bonding position is corrected only by the cumulative positional offset. This prevents the semiconductor chip from continuously shifting laterally in one direction during stacking and bonding.

[0012] In the bonding device of the present invention, the position correction unit can also correct only the position offset of each semiconductor chip of the layer bonded before being detected by the position detection unit when the cumulative position offset is less than a specified threshold, and output it as the bonding position of the next layer.

[0013] As described above, when the cumulative positional deviation is smaller than a predetermined threshold, the bonding position is corrected by the positional deviation of the semiconductor chip in each layer after bonding in each layer, and bonding in the next layer is performed. This can suppress the deviation of bonding in each layer.

[0014] In the joining device of the present invention, the position correction unit outputs a stop instruction to the joining control unit to stop the joining action when the accumulated position deviation amount is greater than a predetermined stop threshold value. The joining control unit can also stop the joining action when a stop instruction is input from the position correction unit.

[0015] As described above, it is possible to detect abnormal tilt during lamination bonding and stop the bonding apparatus.

[0016] In the bonding device of the present invention, when the bonding is terminated in a state where the layers are stacked and bonded to an intermediate layer, and the base member is removed and then set again, the position correction unit can also calculate the intermediate cumulative position offset by accumulating the position offsets from the base member to the semiconductor chip in the intermediate layer while referring to the position database, and correct only the calculated intermediate cumulative position offsets for the positions of the semiconductor chips in the layer bonded before the bonding is terminated, and output them as the corrected bonding position.

[0017] Thus, when the bonding is terminated and the substrate is temporarily removed from the bonding device and then placed back in the bonding device before restarting the bonding, the semiconductor chip can be bonded near the reference position of the substrate. Even if the substrate is removed and reset in the middle of the bonding, the lateral displacement of the semiconductor chip can be suppressed.

[0018] In the bonding device of the present invention, multiple dummy chips can also be stacked and bonded on each bonding area of ​​the base member, and the position detection unit detects each position of the bonding area of ​​the base member and each position of the dummy chips of each layer stacked and bonded on each bonding area of ​​the base member, and saves the data of each detected position in a position database according to each bonding area of ​​the base member. The position correction unit calculates the position offset between the position of the bonding area of ​​the base member and the position of the dummy chip bonded thereto, or the position offset between the position of the bonded dummy chip and the position of the dummy chip bonded directly above it, and saves the calculated position offsets in the position database according to each bonding area of ​​the base member, and based on the position database, corrects the bonding position of each layer when stacking and bonding semiconductor chips.

[0019] As described above, dummy chips are used for bonding in advance, and the positional deviation of the dummy chips from the bottom layer to the top layer is stored in a database. The bonding position is adjusted while referring to the database, thereby suppressing the positional deviation of the semiconductor chips of each layer during stacking bonding.

[0020] The bonding method of the present invention is a bonding method for stacking and bonding a plurality of semiconductor chips on a plurality of bonding regions of a base member, comprising: a position detection step of detecting the positions of the bonding regions of the base member and the positions of the semiconductor chips of each layer stacked and bonded on the bonding regions of the base member, and storing the data of the detected positions in a position database for each bonding region of the base member; a position offset calculation step of calculating the position offset between the position of the bonding region of the base member and the position of the semiconductor chip bonded thereto, or the position offset between the position of the bonded semiconductor chip and the semiconductor chip bonded directly above it, each time the semiconductor chips of each layer are bonded. The method comprises the following steps: calculating the position offset between the positions of the chips, and storing the calculated position offsets in a position database according to each bonding area of ​​the base member; calculating the cumulative position offset by accumulating the position offset from the base member to the semiconductor chip of the bonded layer when the semiconductor chips are stacked and bonded; correcting the position of each semiconductor chip of the bonded layer before the position detection step is performed when the cumulative position offset is greater than a predetermined threshold value; and forming the position of the semiconductor chip of the bonded layer by only the cumulative position offset; and bonding the semiconductor chip of the next layer at the corrected bonding position.

[0021] In the bonding method of the present invention, the position correction step may also correct only the position offsets of each semiconductor chip of the layer bonded before detection by the position detection step, calculated in the position offset calculation step, and use them as the bonding positions of the next layer when the cumulative position offset is less than a specified threshold.

[0022] The bonding method of the present invention may include a bonding stopping step of stopping the bonding operation when the cumulative position deviation amount is equal to or greater than a predetermined stop threshold value.

[0023] Effects of the Invention

[0024] The present invention can suppress the semiconductor chips from continuously shifting laterally in one direction during stack bonding. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a system diagram showing the structure of the bonding apparatus according to the embodiment.

[0026] Figure 2 yes Figure 1 A plan view of the joining device is shown.

[0027] Figure 3 yes Figure 1 Functional block diagram of the control device of the engaging device shown.

[0028] Figure 4It means using Figure 1 The figure is an elevation view showing the lateral positional shift of semiconductor chips in each layer when semiconductor chips are stacked and bonded by the bonding apparatus shown.

[0029] Figure 5 Yes means save in Figure 1 FIG. 1 is a diagram showing a database structure of a position database in a storage unit of a bonding device.

[0030] Figure 6 Yes Figure 1 Flowchart showing the operation of the joining device.

[0031] Figure 7 Yes Figure 1 Flowchart showing the operation of the joining device.

[0032] Figure 8 This is an image of the islands on the substrate captured by a camera.

[0033] Figure 9 Use a camera to shoot Figure 8 An image showing a state where a first-layer semiconductor chip is bonded to the island is shown.

[0034] Figure 10 Use a camera to shoot Figure 9 The image shows a state where the semiconductor chip of the Nth layer is stacked and bonded on the semiconductor chip of the first layer.

[0035] Figure 11 It means using Figure 1 FIG1 is an elevation view showing the lateral positional deviation of semiconductor chips in each layer when the cumulative positional deviation of the semiconductor chips in the Nth layer is equal to or greater than a predetermined threshold value when semiconductor chips are stacked and bonded by the bonding apparatus shown.

[0036] Figure 12 It indicates when the middle layer stops joining and starts joining again. Figure 1 Flowchart showing the operation of the joining device.

[0037] Figure 13 It is a flowchart showing the operation of the bonding device in the following situation, that is, using a dummy chip and using a position database that stores the positions of the island and the positions of the semiconductor chips of each layer after stacking and bonding, the position offset of each layer, and the cumulative position offset of each layer according to each island 41, to perform stacking and bonding of semiconductor chips.

[0038] [Explanation of Reference Numerals]

[0039] 11: Joint head

[0040] 12: Engage the nozzle

[0041] 12z: Z-direction centerline

[0042] 13: Camera

[0043] 13z: Optical Axis

[0044] 15: Gantry track

[0045] 16: Joint platform

[0046] 17: Guide rail

[0047] 20, 21, 22: Semiconductor chips

[0048] 21x, 21y, 41x, 41y: Centerline

[0049] 30: Stacked semiconductor device

[0050] 40: Substrate

[0051] 41: Island

[0052] 42, 43: Mark

[0053] 45: Center position

[0054] 50: Control device

[0055] 51: CPU

[0056] 52: Storage

[0057] 55: Position detection unit

[0058] 56: Location Database

[0059] 57: Position Correction Unit

[0060] 58: Joint control unit

[0061] 60: Field of View

[0062] 100: Jointing device DETAILED DESCRIPTION

[0063] Below, with reference to the attached Figure 1 The bonding apparatus 100 according to the embodiment will be described. Figure 1 、 Figure 2 As shown, the bonding apparatus 100 includes a bonding platform 16 , a gantry track 15 , a bonding head 11 , a bonding nozzle 12 , a camera 13 , and a control device 50 .

[0064] The bonding apparatus 100 stacks and bonds a plurality of semiconductor chips 20 onto a plurality of islands 41 on a substrate 40. In the following description, when the stacked layers are distinguished, the semiconductor chips of the first and second layers are referred to as semiconductor chips 21 and 22, respectively, and the semiconductor chip of the Nth layer is referred to as semiconductor chip 20(N). When the stacked layers are not distinguished, they are referred to as semiconductor chip 20.

[0065] The bonding platform 16 uses two guide rails 17 on its upper surface to guide the substrate 40, which serves as the base member, from both sides and secure the substrate 40 to the upper surface by suction. The bonding platform 16 also houses a heater to heat the substrate 40. The substrate 40 is guided by the guide rails 17 and transported in the X-direction. In the following description, the transport direction of the substrate 40 is the X-direction, the direction perpendicular to the X-direction on the horizontal plane is the Y-direction, and the vertical direction is the Z-direction.

[0066] The gantry track 15 is provided above the bonding stage 16 and moves in the X direction. The bonding head 11 moves in the Y direction guided by the gantry track 15. Therefore, the bonding head 11 can move in the X and Y directions relative to the substrate 40 fixed by suction on the bonding stage 16.

[0067] The bonding nozzle 12 is mounted on the bonding head 11 and moves along the Y direction with the bonding head 11. Furthermore, the bonding nozzle 12 includes a chuck at its lower end that attracts and holds the semiconductor chip 20, and is movable in the Z direction. The bonding nozzle 12 moves in the Z direction to bond the semiconductor chip 20, which is attracted and held at its tip, to the island 41 serving as the bonding area of ​​the substrate 40, or to the semiconductor chip 20 already bonded to the island 41.

[0068] The camera 13 is mounted on the bonding head 11 and moves in the Y direction together with the bonding nozzle 12 to capture images of the islands 41 of the substrate 40 or the semiconductor chips 20 bonded to the islands 41. The optical axis 13z of the camera 13 is separated from the Z-direction centerline 12z of the bonding nozzle 12 by a deviation A in the Y direction.

[0069] The bonding head 11, gantry rail 15, and bonding nozzle 12 are connected to a control device 50 and operate according to commands from the control device 50. The camera 13 is connected to the control device 50, and image data captured by the camera 13 is input to the control device 50. The control device 50 is a computer that internally includes a central processing unit (CPU) 51, which is a processor that performs information processing, and a storage unit 52 that stores operating programs, operating data, and the like.

[0070] like Figure 3As shown, the control device 50 includes four functional blocks: a position detection unit 55, a position database 56, a position correction unit 57, and a joint control unit 58. The position detection unit 55, the position correction unit 57, and the joint control unit 58 are implemented by the CPU 51 executing an operating program stored in the storage unit 52. The position database 56 is also implemented by the storage unit 52.

[0071] The position detection unit 55 detects the position of the island 41 on the substrate 40 based on the image of the island 41 captured by the camera 13. Furthermore, the position detection unit 55 detects the positions of the semiconductor chips 20 of each layer stacked and bonded to the island 41 of the substrate 40 based on the image of the semiconductor chips 20 of each layer bonded to the island 41. The position detection unit 55 stores the detected positions in a position database 56, which will be described later.

[0072] The position correction unit 57 corrects the joining position while referring to the position database 56 , and outputs the corrected joining position to the joining control unit 58 .

[0073] The bonding control unit 58 bonds the semiconductor chip 20 at the corrected bonding position input from the position correction unit 57 .

[0074] Secondly, refer to Figure 4 、 Figure 5 , the structure of the position database 56 will be described. If the bonding apparatus 100 stacks and bonds a plurality of semiconductor chips 20 on a plurality of islands 41 of a substrate 40, then Figure 1 As shown, the semiconductor chips 20 are stacked in the Z direction to form a stacked semiconductor device 30. When the semiconductor chips 20 are stacked correctly, the stacked semiconductor device 30 is stacked vertically upward with respect to the substrate 40.

[0075] However, due to manufacturing errors of the various parts of the bonding apparatus 100 or thermal deformation of the bonding apparatus 100, there are cases such as Figure 4 As in the example shown, the bonding position of the semiconductor chip 20 is laterally shifted. Figure 4 In the figure, the semiconductor chip 21 of the first layer is bonded to the island 41 with an offset of only Δy1 in the negative Y direction relative to the island 41 of the substrate 40. Similarly, the semiconductor chip 22 of the second layer is bonded with an offset of only Δy2 in the negative Y direction relative to the semiconductor chip 21 of the first layer. Similarly, the semiconductor chip 20 (N) of the Nth layer is bonded with an offset of only ΔyN in the negative Y direction relative to the semiconductor chip 20 (N-1) of the N-1th layer. In the case where the semiconductor chips 20 are bonded with an offset in position as described above, the cumulative position offset from the island 41 to the first layer is Δy1, the cumulative position offset to the second layer is Δy1+Δy2, and the cumulative position offset to the Nth layer is

[0076] [Formula 1]

[0077]

[0078] like Figure 5 As shown, the position database 56 stores the positions of the islands 41 of the substrate 40 and the positions of the semiconductor chips 20 in each layer of the stacked and bonded semiconductor chips 20 , the positional deviation of each layer, and the accumulated positional deviation of each layer for each island 41 of the substrate 40 .

[0079] Figure 5 In FIG. 1 , (x0, y0) represents the XY coordinate position of the center of the island 41 calculated by the position detection unit 55 based on the image of the island 41 on the substrate 40 captured by the camera 13. Furthermore, (x1, y1) represents the XY coordinate position of the center of the semiconductor chip 21 calculated by the position detection unit 55 based on the image of the semiconductor chip 21 on the first layer captured by the camera 13. Similarly, (xN, yN) represents the XY coordinate position of the center of the semiconductor chip 20(N) calculated by the position detection unit 55 based on the image of the semiconductor chip 20(N) on the Nth layer captured by the camera 13.

[0080] Furthermore, (Δx1, Δy1) represents the positional offset between the center coordinates (x0, y0) of the island 41 of the substrate 40 and the center coordinates (x1, y1) of the semiconductor chip 21 in the first layer, calculated by the position correction unit 57. Here, Δx1 = x1 - x0, and Δy1 = y1 - y0. Similarly, (ΔxN, ΔyN) represents the positional offset between the center coordinates of the semiconductor chip 20 (N) in the Nth layer and the center coordinates of the semiconductor chip 20 (N-1) in the N-1st layer, where ΔxN = x(N) - x(N-1) and ΔyN = y(N) - y(N-1).

[0081] The cumulative positional offset is obtained by accumulating the positional offsets of the center positions of the semiconductor chips 20 from the island 41 to the Nth layer. The cumulative positional offset of the semiconductor chip 21 on the first layer is the same as the positional offset (Δx1, Δy1) between the center coordinates (x0, y0) of the island 41 and the center coordinates (x1, y1) of the semiconductor chip 21 on the first layer. The cumulative positional offsets of the N layers above the second layer are the cumulative values ​​of the positional offsets up to the Nth layer, which is

[0082] [Formula 2]

[0083]

[0084] Secondly, refer to Figures 6 to 11 , the operation of the bonding apparatus 100 according to the embodiment will be described. Figure 6 Step S101, Figure 8As shown, the bonding control unit 58 moves the bonding head 11 along the XY direction by operating the bonding head 11 and the gantry rail 15 so that the center of the field of view 60 of the camera 13 becomes the center of the island 41 of the substrate 40. Figure 8 As shown, if the center of the island 41 is located in the center of the field of view 60 of the camera 13, the position detection unit 55 receives the image of the island 41 captured by the camera 13. The position detection unit 55 analyzes the image to detect the positions of the markers 42 and 43, detects the center line 41x in the X direction and the center line 41y in the Y direction from the positions of the two markers 42 and 43, and calculates the XY coordinates (x0, y0) of the center position 45 of the island 41 as the intersection of the two center lines 41x and 41y. The position detection unit 55 calculates the calculated XY coordinates (x0, y0) as shown in FIG. Figure 5 The data is stored in the location database 56.

[0085] In this case, since the position offset is not calculated, the position correction unit 57 outputs the XY coordinates (x0, y0) of the center position 45 of the island 41 stored in the position database 56 as the corrected bonding position of the first layer semiconductor chip 21 to the bonding control unit 58.

[0086] Figure 6 In step S102, the bonding control unit 58 moves the bonding head 11 in the Y direction by a deviation A so that the Z-direction center line 12z of the bonding nozzle 12 reaches the XY coordinate (x0, y0). The semiconductor chip 20 is suctioned and fixed at the tip of the bonding nozzle 12 so that the center coordinate XY corresponds to the position of the Z-direction center line 12z. Therefore, if the Z-direction center line 12z of the bonding nozzle 12 is aligned with the XY coordinate (x0, y0), the center position 215 of the semiconductor chip 21 will be at the same XY position as the center position 45 of the island 41. The bonding control unit 58 then lowers the bonding nozzle 12 to bond the first-layer semiconductor chip 21 to the island 41.

[0087] Figure 6 In step S103, the bonding control unit 58 moves the bonding head 11 to the negative side in the Y direction by a deviation A so that the center of the field of view 60 of the camera 13 becomes the center of the semiconductor chip 21. The position detection unit 55 receives the position information from the camera 13. Figure 9The image of the semiconductor chip 21 of the first layer bonded as shown enters the field of view 60. The position detection unit 55 analyzes the image to detect the positions of the marks 212 and 213 of the semiconductor chip 21 of the first layer, detects the center line 21x in the X direction and the center line 21y in the Y direction from the positions of the two marks 212 and 213, and calculates the XY coordinates (x1, y1) of the center position 215 of the semiconductor chip 21 as the intersection of the two center lines 21x and 21y. The position detection unit 55 calculates the calculated XY coordinates (x1, y1) as shown in FIG. Figure 5 The data is stored in the location database 56.

[0088] Figure 6 In step S104, the position correction unit 57 calculates the positional offset (Δx1, Δy1) between the XY coordinates (x0, y0) of the center position 45 of the island 41 stored in the position database 56 and the XY coordinates (x1, y1) of the center position 215 of the first layer semiconductor chip 21 bonded to the island 41. Figure 6 In step S105, the calculated position offset (Δx1, Δy1) is Figure 5 The values ​​are stored in the position database 56. Here, (Δx1, Δy1) are the positional deviations of the semiconductor chips 21 in the first layer, and Δx1 = x1 - x0, and Δy1 = y1 - y0.

[0089] Figure 6 In step S106, the position correction unit 57 sets the calculated positional offset of the semiconductor chip 21 of the first layer as the cumulative positional offset of the first layer. Figure 5 The data is stored in the location database 56.

[0090] Figure 6 In step S107, the position correction unit 57 corrects only the position offset (Δx1, Δy1) of the first-layer semiconductor chip 21 using the XY coordinates (x1, y1) of the center position 215 of the first-layer semiconductor chip 21, and outputs it to the bonding control unit 58 as the bonding position of the second-layer semiconductor chip 22.

[0091] The control device 50 Figure 7 In step S108, the count value N is set to 2, and the execution is repeated. Figure 7 The semiconductor chips 20 are stacked and bonded through steps S109 to S119 .

[0092] Figure 7 In step S109, the joint control unit 58 Figure 10 As shown in FIG. 1 , the semiconductor chip 20 (N) of the Nth layer is bonded. Furthermore, the position detection unit 55 is Figure 7In step S110, similarly to the case of the semiconductor chip 21 on the first layer, the image of the semiconductor chip 20(N) on the Nth layer captured by the camera 13 is received, the center line Nx in the X direction and the center line Ny in the Y direction are detected from the positions of the two marks 202(N) and 203(N), and the XY coordinates (xN, yN) of the center position 205(N) are calculated. Then, the position detection unit 55 outputs the calculated XY coordinates (xN, yN) as shown in FIG. Figure 5 The data is stored in the location database 56.

[0093] Figure 7 In step S111, the position correction unit 57 calculates the positional offset (ΔxN, ΔyN) between the XY coordinates (xN-1, yN-1) of the center position 205(N-1) of the semiconductor chip 20(N-1) on the N-1th layer and the XY coordinates (xN, yN) of the center position 205(N) of the semiconductor chip 20(N) on the Nth layer stored in the position database 56. Figure 6 In step S112, the calculated positional offset (ΔxN, ΔyN) of the semiconductor chip 20 (N) on the Nth layer is converted into Figure 5 The values ​​are stored in the position database 56. Here, (ΔxN, ΔyN) are ΔxN=xN-(xN-1) and ΔyN=yN-(yN-1).

[0094] Figure 7 In step S113, the position correction unit 57 adds the calculated positional offset of the semiconductor chip 20 (N) on the Nth layer to the accumulated positional offset on the N-1th layer to calculate the accumulated positional offset on the Nth layer. Figure 5 The accumulated position offset of the Nth layer is

[0095] [Formula 3]

[0096]

[0097] The position correction unit 57 is Figure 7 In step S114, it is determined whether the accumulated position deviation of the Nth layer is greater than a predetermined threshold value. The position correction unit 57 is executed when the accumulated position deviation of the Nth layer is less than the predetermined threshold value. Figure 7 If the judgment in step S114 is NO, enter Figure 7In step S119, the XY coordinates (xN, yN) of the center position 205 of the semiconductor chip 20 (N) of the Nth layer are corrected by only the position offset (ΔxN, ΔyN) of the semiconductor chip 20 (N) of the Nth layer, and (xN+1)=xN+ΔxN, (yN+1)=yN+ΔyN are output to the bonding control unit 58 as the corrected bonding position of the semiconductor chip 20 (N+1) of the N+1th layer, and the process proceeds to the bonding control unit 58. Figure 7 Step S117.

[0098] The control device 50 Figure 7 In step S117, the count value N is increased by only 1. Figure 7 In step S118, it is determined whether N exceeds the total stacking number Nend. Figure 7 If the judgment is NO in step S118, the system returns to Figure 7 In step S109 , the semiconductor chip 20 (N+1) of the N+1 layer is bonded.

[0099] As described above, when the accumulated position offset is less than the predetermined threshold, after bonding each layer, the bonding position is corrected by only the position offset (ΔxN, ΔyN) of the semiconductor chip 20 of each layer to perform bonding of the next layer, thereby suppressing the offset of bonding of each layer.

[0100] On the other hand, when the number of stacked layers increases and the accumulated position deviation amount becomes larger than a predetermined threshold value, the position correction unit 57 Figure 7 If the judgment is YES in step S114, the position correction unit 57 enters Figure 7 In step S115, it is determined whether the accumulated position deviation of the Nth layer is greater than the stop threshold value which is greater than the predetermined threshold value. Figure 7 If the judgment in step S115 is NO, enter Figure 7 In step S116, the XY coordinates (xN, yN) of the center position 205(N) of the semiconductor chip 20(N) on the Nth layer are corrected by only the accumulated position deviation of the semiconductor chip 20(N) on the Nth layer.

[0101] [Formula 4]

[0102]

[0103] The corrected bonding position of the semiconductor chip 20 (N+1) in the N+1th layer is output to the bonding control unit 58 .

[0104] The bonding control unit 58 moves the Z-direction center line 12z of the bonding nozzle 12 to the XY coordinate system.

[0105] [Formula 5]

[0106]

[0107] The bonding head 11 is moved in the XY direction. At the front end of the bonding nozzle 12, the semiconductor chip 20 (n+1) of the N+1 layer is adsorbed and fixed in such a way that the center coordinate XY becomes the position of the center line 12z in the Z direction. Therefore, if the center line 12z in the Z direction of the bonding nozzle 12 is aligned with the XY coordinate

[0108] [Formula 6]

[0109]

[0110] The center position 205(N+1) of the semiconductor chip 20(N+1) is aligned to the center position 45 of the island 41 of the substrate 40. Then, the bonding control unit 58 lowers the bonding nozzle 12 to bond the semiconductor chip 20(N+1) of the N+1th layer to the semiconductor chip 20(N). Figure 11 As shown, the center position 205 (N+1) of the semiconductor chip 20 (N+1) in the N+1th layer can be aligned with the center position 45 of the island 41 and bonded.

[0111] As described above, by stacking and bonding the semiconductor chips 20, as shown in FIG. Figure 11 As shown, even when the semiconductor chips 20 of each layer are stacked while continuously shifting in one direction, the semiconductor chips 20 can be prevented from continuously shifting in one direction beyond a predetermined threshold during stacking and bonding.

[0112] Furthermore, the control device 50 Figure 7 In step S117, the count value N is increased by only 1. Figure 7 In step S118, it is determined whether N exceeds the total stacking number Nend. Figure 7 If the judgment is NO in step S118, the system returns to Figure 7 In step S109 , the semiconductor chip 20 (N+1) of the N+1 layer is bonded.

[0113] In addition, the control device 50 Figure 7 If the answer is YES in step S118, the engagement operation is terminated.

[0114] In addition, the position correction unit 57 Figure 7 If the judgment in step S115 is YES, enter Figure 7 In step S120, a joining stop command is output to the joining control unit 58. Upon receiving the joining stop command, the joining control unit 58 stops the joining operation. In this way, abnormal tilt during lamination joining can be detected and the joining apparatus 100 can be stopped.

[0115] As described above, when the bonding device 100 stacks and bonds semiconductor chips 20 in multiple islands 41 of a substrate 40, the positions of each island 41 and the positions of each layer of semiconductor chips 20 that have been stacked and bonded and the position offset of each layer are saved in a position database 56 for each island 41 of the substrate 40, and the bonding positions of each layer of semiconductor chips 20 in each island 41 are corrected while referring to this position database 56.

[0116] Thus, even when the direction and magnitude of the positional deviation vary depending on the islands 41 , it is possible to perform appropriate correction of the bonding position for each island.

[0117] Secondly, refer to Figure 12 、 Figure 13 , the operation of the following situation is explained: stacking bonding is performed until the middle layer M which is less than the total stacking number Nend, and then the bonding is terminated, the substrate 40 stacked with the semiconductor chip 20 is taken out from the bonding platform 16 and inspected, and then the substrate 40 is adsorbed and fixed to the bonding platform 16 again and stacking bonding is started again from the M+1th layer.

[0118] The stacking and bonding up to the Mth layer is done by Figure 6 、 Figure 7 Therefore, the position of the island 41, the positions of the semiconductor chips 20 in each layer from the first layer to the Mth layer, the positional offset of each layer, and the accumulated positional offset of each layer from the first layer to the Mth layer are stored in the position database 56.

[0119] If the position detection unit 55 is Figure 12 In step S201, the connection is started again. Figure 12 As shown in step S202, similarly to the case of the semiconductor chip 21 on the first layer, the image of the semiconductor chip 20 (M) on the Mth layer captured by the camera 13 is received, and the XY coordinates (xM, yM) of the center position 205 (M) are calculated based on the positions of the two marks 202 (M) and 203 (M). Then, the position detection unit 55 calculates the calculated XY coordinates (xM, yM) as shown in FIG. Figure 5 The position detection unit 55 is stored in the position database 56 before the engagement is terminated. Figure 7 The XY coordinates (xM, yM) of the semiconductor chip 20 (M) on the Mth layer detected in step S110 are rewritten and updated.

[0120] The position correction unit 57 is as follows Figure 12As shown in step S203, the intermediate cumulative position offsets up to the Mth layer stored in the position database 56 are added to the XY coordinates (xM, yM) of the semiconductor chip 20 (M) in the Mth layer, so as to

[0121] [Formula 7]

[0122]

[0123] The corrected bonding position of the semiconductor chip 20 (M+1) in the M+1th layer is calculated in the above-described manner and is output to the bonding control unit 58 .

[0124] Furthermore, the control device 50 Figure 12 In step S204, the count value N is set to M+1 and the Figure 7 In step S109 , the semiconductor chip 20 (M+1) of the M+1th layer is bonded.

[0125] Then, the control device 50 repeatedly executes Figure 7 The semiconductor chips 20 are stacked and bonded according to steps S109 to S119. Once bonding is completed up to the total number of stacked chips Nend, the bonding operation is stopped.

[0126] As described above, after performing stack bonding up to the middle layer M, the bonding apparatus 100 can resume stack bonding from the M+1th layer onwards, aligning the center position 205(M+1) of the semiconductor chip 20(M+1) in the M+1th layer with the center position 45 of the island 41 for bonding. Therefore, after pausing bonding and removing the substrate 40 from the bonding stage 16, when the substrate 40 is replaced and bonding resumes, the state in which the semiconductor chip 20 is laterally offset in one direction can be reset, thereby preventing the semiconductor chip 20 from significantly offsetting laterally after bonding resumes.

[0127] Furthermore, the position database 56 stores the positions of the semiconductor chips 20 in each of the first to Mth layers of the semiconductor chips 20 bonded to all islands 41, the positional offset of each layer, and the cumulative positional offset of each layer from the first to Mth layers. Therefore, even when stack bonding of the M+1th layer and beyond is performed using a different bonding apparatus 100 rather than the same bonding apparatus 100, significant lateral shifting of the semiconductor chips 20 can be suppressed after bonding is resumed.

[0128] Next, a description will be given of a case where the semiconductor chip 20 is bonded after test bonding using a dummy chip made of glass or the like in the bonding apparatus 100 .

[0129] In this case, the control device 50 executes Figure 6 Steps S101 to Figure 7After step S108, continue to execute Figure 7 The dummy chip is stacked to the Nend layer through steps S109 to S119, and the positions of each island 41 and the positions of the semiconductor chips 20 of each layer stacked and bonded, the position offset of each layer, and the cumulative position offset of each layer are saved in the position database 56 according to each island 41.

[0130] Furthermore, when the semiconductor chips 20 are stacked and bonded, instead of calculating the positional deviation amount of each layer and the cumulative positional deviation amount of each layer, the calculation may be performed as follows: Figure 13 As shown in steps S301 and S303, the position of the island 41 and the positions of the semiconductor chips 20 of each layer are detected. Figure 13 As in step S304, each detected position is corrected by only the positional deviation amount of each layer stored in the position database 56, and the stacking and joining of each layer is performed as the corrected joining position of the next layer.

[0131] In this case, since the positional deviation amount of each layer and the cumulative positional deviation amount of each layer are not calculated, it is possible to suppress the semiconductor chip 20 from continuously deviating in one direction and to perform stack bonding at a high speed.

[0132] Furthermore, correction values ​​can be obtained by performing test bonding using dummy chips. After stacking and bonding the semiconductor chips 20, they can be mounted on all or part of the islands 41, and the positional offset of each layer and the cumulative position offset can be measured. In this case, the measured values ​​from the stacking and bonding can be fed back into the correction values ​​obtained in the test bonding. This reduces the effects of strain on the stage or gantry rail 15 caused by heat or time changes, allowing for more precise stacking and bonding.

[0133] As described above, the bonding apparatus 100 according to the embodiment can suppress the semiconductor chip 20 from continuously shifting in one direction laterally during stack bonding.

[0134] In the above description, the bonding apparatus 100 is described as stacking and bonding the semiconductor chips 20 on the islands 41 of the substrate 40 . However, the present invention is not limited thereto and can also be applied to stacking and bonding the semiconductor chips 20 on a plurality of base chips formed on a wafer.

[0135] In the above description, the rail guiding the bonding head 11 is described as the gantry rail 15. However, the gantry rail 15 is merely an example. For example, the ends of the guide rail 17 may be fixed. In this case, the bonding head 11 can be driven in one direction only, while the stage is driven in a direction orthogonal to the direction. Furthermore, the guide rail 17 can be used even if it is not in a gantry shape.

Claims

1. A bonding device for bonding a plurality of semiconductor chips to a plurality of bonding regions of a base member, wherein: include: a position detecting unit that detects positions of the respective bonding regions of the base member and positions of the respective layers of semiconductor chips stacked and bonded to the respective bonding regions of the base member, and stores data of the detected positions in a position database for each bonding region of the base member; a position correction unit that corrects the joining position while referring to the position database and outputs the corrected joining position; as well as The bonding control unit performs bonding of the semiconductor chip based on the corrected bonding position input from the position correction unit, wherein The position correction unit calculates a positional offset between the position of the bonding region of the base member and the position of the semiconductor chip bonded to the bonding region, or a positional offset between the position of one of the bonded semiconductor chips and the position of the semiconductor chip bonded directly above the one of the semiconductor chips, each time the semiconductor chips of each layer are bonded, and stores the calculated positional offsets in the position database for each bonding region of the base member. The accumulated positional deviation amount is calculated by accumulating the positional deviation amount from the base member to the semiconductor chip of the bonded layer when the semiconductor chips are stacked and bonded. When the accumulated positional deviation is equal to or greater than a predetermined threshold, correcting only the accumulated positional deviation for each position of each semiconductor chip in the layer bonded immediately before detection by the position detection unit and outputting the corrected bonded position; The bonding control unit performs bonding of a semiconductor chip of a next layer at the corrected bonding position input from the position correction unit.

2. The joining device according to claim 1, wherein: When the accumulated positional deviation is smaller than a predetermined threshold, the position correcting unit corrects only the positional deviation of each semiconductor chip in a layer bonded just before detection by the position detecting unit and outputs the corrected position as the bonding position of the next layer.

3. The joining device according to claim 1 or 2, characterized in that: The position correction unit outputs a stop instruction to the engagement control unit to stop the engagement operation when the cumulative position deviation amount is equal to or greater than a predetermined stop threshold value, and The joining control unit stops the joining operation when the stop command is input from the position correction unit.

4. The joining device according to claim 1 or 2, characterized in that: The position correction portion is configured such that, in the case where the bonding is stopped in a state where the layers are laminated and bonded to the intermediate layer, and the base member is removed and then set again, While referring to the position database, each position deviation amount from the base member to the semiconductor chip in the intermediate layer is accumulated to calculate an intermediate cumulative position deviation amount. For each position of the semiconductor chip in the layer bonded immediately before the bonding is terminated, only the calculated intermediate cumulative positional deviation amount is corrected and output as a corrected bonding position.

5. The joining device according to claim 1 or 2, characterized in that: stacking and bonding a plurality of dummy chips on each bonding area of ​​the base member; The position detection unit detects each position of the bonding area of ​​the base member and each position of each layer of dummy chips stacked and bonded to each bonding area of ​​the base member, and stores data of each detected position in the position database for each bonding area of ​​the base member; The position correction unit calculates a positional offset between the position of the bonding area of ​​the base member and the position of the dummy chip bonded to the bonding area, or a positional offset between the position of one of the bonded dummy chips and the position of the dummy chip bonded directly above the one of the dummy chips, and stores the calculated positional offsets in the position database for each bonding area of ​​the base member; and Based on the position database, the bonding position of each layer when the semiconductor chips are stacked and bonded is corrected.

6. A bonding method for laminating and bonding a plurality of semiconductor chips on a plurality of bonding regions of a base member, characterized in that: include: a position detection step of detecting the positions of the respective bonding regions of the base member and the positions of the respective semiconductor chips of the respective layers stacked and bonded to the respective bonding regions of the base member, and storing the data of the detected positions in a position database for each bonding region of the base member; a position offset calculating step of calculating, each time the semiconductor chips of each layer are bonded, a position offset between the position of the bonding region of the base member and the position of the semiconductor chip bonded to the bonding region, or a position offset between the position of one of the bonded semiconductor chips and the position of the semiconductor chip bonded immediately above the one of the semiconductor chips, and storing the calculated position offsets in the position database for each bonding region of the base member; a cumulative positional deviation calculating step of accumulating positional deviations from the base member to the semiconductor chip of the bonded layer when the semiconductor chips are stacked and bonded, thereby calculating a cumulative positional deviation; a position correction step of, when the accumulated position shift amount is equal to or greater than a predetermined threshold value, correcting only the accumulated position shift amount for each position of each semiconductor chip in a layer bonded before detection by the position detection step and setting the position as a bonding position for a next layer; as well as In the bonding step, the semiconductor chip of the next layer is stacked and bonded at the corrected bonding position.

7. The bonding method according to claim 6, wherein: In the position correction step, when the accumulated position offset is less than a predetermined threshold value, only the position offsets of each semiconductor chip of the layer that is to be joined before detection by the position detection step are corrected, as the joining positions of the next layer, which are calculated in the position offset calculation step.

8. The joining method according to claim 6 or 7, characterized in that: The method includes an engagement stopping step of stopping the engagement operation when the cumulative position deviation amount is equal to or greater than a predetermined stop threshold value.

Images