Chip mounting apparatus and chip mounting method

Abstract

To provide a chip mounting device and a chip mounting method capable of attaching paste to a heated chip and mounting it on a substrate with a simple configuration.SOLUTION: In a chip mounting method, a heating tool holding a chip is lowered to the dipping positions P1 to P6 set on a flat portion 9a where a paste film to cause the paste adheres to the chip, and the heating tool is lowered towards the substrate to mount the chip to which the paste adheres on the substrate, a paste application operation for adhering the paste to the chip and a film forming operation for forming a paste film on the flat portion 9a are alternately performed, and during the paste application operation, a dipping position P2 different from a dipping position P1 used in the previous paste application operation is used.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a chip mounting apparatus and a chip mounting method for attaching paste to a chip and mounting it on a substrate.

Background Art

[0002] As a method for manufacturing components, there is known a method in which a process of attaching paste such as flux to the lower surface of a bumped chip, a process of mounting the chip on a substrate, and a process of thermocompression bonding the chip to the substrate are continuously executed (for example, Patent Document 1). Patent Document 1 discloses a bonding apparatus including a rotary head in which a plurality of work holding heads and a plurality of thermocompression bonding tools are alternately arranged. This bonding apparatus picks up a work at a work supply station while pitch-rotating the rotary head, attaches paste to the work at a mucilage application station, mounts it on a substrate at a bonding station, and then thermocompression bonds the chip mounted on the substrate with a thermocompression bonding tool.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the prior art including Patent Document 1, although it is possible to prevent the paste supplied from the mucilage application station from being deteriorated by heating by separately providing a work holding head for holding a chip and mounting it on a substrate and a thermocompression bonding tool having a heat source, there is room for further improvement because the configuration of the apparatus is complicated and large-scale.

[0005] Therefore, the present invention aims to provide a chip mounting apparatus and a chip mounting method that can attach paste to a heated chip and mount it on a substrate with a simple configuration. [Means for solving the problem]

[0006] The chip mounting apparatus of the present invention is a chip mounting apparatus that lowers a heating tool holding a chip to a dipping position set on a flat portion on which a paste film has been formed, thereby adhering the paste to the chip, and then lowers the heating tool toward a substrate to mount the chip with the paste attached to it onto the substrate, wherein the paste adhesion operation, in which the paste is adhered to the chip, and the film formation operation, in which a paste film is formed on the flat portion, are performed alternately, and a different dipping position is used during the paste adhesion operation than the dipping position used in the previous paste adhesion operation. Then, the film formation operation is performed, including the dipping position that was used once in the paste application operation. .

[0007] The present invention provides a chip mounting method comprising: lowering a heating tool holding the chip to a dipping position set on a flat surface where a paste film is formed to adhere the paste to the chip; and lowering the heating tool toward a substrate to mount the chip with the paste attached to it onto the substrate, wherein the paste adhesion operation to adhere the paste to the chip and the film formation operation to form a paste film on the flat surface are performed alternately, and a different dipping position is used during the paste adhesion operation than the dipping position used in the previous paste adhesion operation. Then, the film formation operation is performed, including the dipping position that was used once in the paste application operation. . [Effects of the Invention]

[0008] According to the present invention, a paste can be applied to a heated chip and mounted onto a substrate using a simple configuration. [Brief explanation of the drawing]

[0009] [Figure 1] Front view showing the configuration of the main part of a chip mounting device according to one embodiment of the present invention. [Figure 2]Plan view showing the configuration of the main part of a chip mounting device according to one embodiment of the present invention. [Figure 3] Plan view showing the configuration of the paste supply unit included in a chip mounting apparatus according to one embodiment of the present invention. [Figure 4] A side cross-sectional view showing the configuration of the paste supply unit of a chip mounting apparatus according to one embodiment of the present invention. [Figure 5] (a) Diagram illustrating paste stirring operation in the paste supply unit of a chip mounting apparatus according to one embodiment of the present invention (b) Diagram illustrating film formation operation (c) Diagram illustrating paste adhesion operation [Figure 6] (a)(b)(c)(d) Diagram illustrating the effect of heated chips on the paste film in the paste supply section of a chip mounting apparatus according to one embodiment of the present invention. [Figure 7] This diagram illustrates the multiple dipping positions set on the flat portion of the paste supply unit in a chip mounting apparatus according to one embodiment of the present invention. [Modes for carrying out the invention]

[0010] An embodiment of the present invention will be described in detail below with reference to the drawings. The configurations, shapes, etc. described below are illustrative examples for illustrative purposes and can be modified as appropriate according to the specifications of the chip mounting device and paste supply unit. In the following, corresponding elements are denoted by the same reference numerals in all drawings, and redundant explanations are omitted. In Figure 1 and some parts described later, the X-axis in the substrate transport direction (up and down direction in Figure 2) and the Y-axis in the substrate transport direction (left and right direction in Figure 1) are shown as two mutually orthogonal axes in the horizontal plane. In Figure 1 and some parts described later, the Z-axis (up and down direction in Figure 1) is shown as the height direction perpendicular to the horizontal plane.

[0011] First, with reference to Figures 1 and 2, the main components of the chip mounting apparatus (hereinafter simply referred to as "mounting apparatus 1") will be described. Mounting apparatus 1 has the function of heating the chip, attaching paste to the chip, and mounting the paste-coated chip onto the substrate. Mounting apparatus 1 has a chip supply stage 2, a paste transfer stage 3, and a bonding stage 4 arranged along the Y axis.

[0012] The chip supply stage 2 has the function of supplying multiple chips 5 on which bumps 5a have been formed. Multiple chips 5, which have been divided into individual pieces in the wafer state, are held on an adhesive sheet 6 with the bumps 5a facing upwards. The adhesive sheet 6 on which the chips 5 are attached is placed on the chip supply stage 2 while attached to a ring holder 7. The chip supply stage 2 is equipped with a ring holder movement mechanism (not shown) that moves the ring holder 7 in the X-axis and Y-axis directions. The ring holder movement mechanism is controlled by a control unit C provided in the mounting apparatus 1.

[0013] In Figures 1 and 2, the paste transfer stage 3 has a paste supply unit 10, which has a container 9 containing paste 8 and is controlled by the control unit C. A paste film 8a is formed on the flat portion 9a of the container 9 (Figure 5(b)). The detailed configuration of the paste supply unit 10 will be described later. The bonding stage 4 has a substrate holder 12 that holds the substrate 11. The bonding stage 4 is equipped with a substrate holder movement mechanism (not shown) that moves the substrate holder 12 in the X-axis and Y-axis directions. The substrate holder movement mechanism is controlled by the control unit C.

[0014] Above the chip supply stage 2 is a pickup tool 13 for picking up chips 5 from the adhesive sheet 6. The pickup tool 13 is supported by a pickup head 14 controlled by a control unit C. In the pickup process for picking up chips 5 from the chip supply stage 2, the pickup head 14 first lowers the pickup tool 13 with the surface that holds the chip 5 facing downwards to pick up the chip 5 from the adhesive sheet 6. Next, the pickup head 14 rotates the pickup tool 13 180 degrees so that the surface that holds the chip 5 faces upwards (arrow a). As a result, the chip 5 is inverted and held by the pickup tool 13 with the bump 5a facing downwards.

[0015] In Figures 1 and 2, a heating tool 15 is positioned above the pickup tool 13, paste supply unit 10, and substrate holder 12 to receive and hold the chip 5 held by the pickup tool 13. The heating tool 15 is supported by a bonding head 16 controlled by a control unit C. The bonding head 16 moves the heating tool 15 in the Y-axis direction and the vertical direction (Z-axis direction). The heating tool 15 has a built-in heater 15a that heats the held chip 5 (see Figure 5(c)).

[0016] In Figure 1, the heating tool 15 receives the chip 5 from the pickup tool 13 with the bump 5a facing downwards (receiving step). Next, the heating tool 15 applies paste 8 to the chip 5 using the paste supply unit 10 (arrow b) (paste application step), and mounts it onto the substrate 11 held by the substrate holder 12 (arrow c) (mounting step). While receiving the chip 5 and mounting it onto the substrate 11, the heating tool 15 heats the held chip 5 to a predetermined temperature (for example, 200°C), and mounts the heated chip 5 onto the substrate 11. In other words, the chip 5 is heated by the heating tool 15 from the receiving step to the mounting step.

[0017] Next, referring to FIGS. 3 and 4, the detailed configuration of the paste supply unit 10 will be described. FIG. 4 is a cross-sectional view taken along the line A-A in FIG. 3. The paste supply unit 10 includes a container 9 for containing the paste 8 on the upper part of an upper plate 19 supported from below by a plurality of columns 18 arranged on the upper surface of a lower plate 17. The bottom surface of the recess of the container 9 is a flat portion 9a on which the paste 8 is formed in a film shape. On the upper surface of the upper plate 19, two rails 20 extending along the X-axis are arranged. On the lower surface of the container 9, a plurality of sliders 21 sliding along the rails 20 are arranged.

[0018] Between the lower plate 17 and the upper plate 19, a motor 22 controlled by a control unit C is arranged. The motor 22 rotationally drives a feed screw 23 extending along the X-axis. A nut portion 24 is engaged with the feed screw 23. By the forward and reverse rotation of the feed screw 23, the nut portion 24 reciprocates along the X-axis. A connecting member 25 that protrudes upward through an opening 19a formed in the upper plate 19 and is connected to the container 9 is connected to the nut portion 24. With this configuration, when the motor 22 rotates the feed screw 23 forward and backward, the container 9 reciprocates along the X-axis on the rails 20.

[0019] In FIGS. 3 and 4, above the container 9, a blade 26 and a squeegee 27 extending along the Y-axis are arranged in parallel. The blade 26 is supported so as to be able to move up and down by a blade lifting and lowering unit 28. The squeegee 27 is supported so as to be able to move up and down by a squeegee lifting and lowering unit 29. The blade lifting and lowering unit 28 and the squeegee lifting and lowering unit 29 are controlled by the control unit C.

[0020] Next, referring to FIG. *********** will be described.

[0021] In Figure 5(a), during the paste stirring operation, with the container 9 in a position far from the motor 22 (state as in Figure 3), the control unit C raises the squeegee 27 using the squeegee lifting unit 29, moving the lower surface of the squeegee 27 away from the flat portion 9a of the container 9. Next, the control unit C lowers the blade 26 using the blade lifting unit 28, bringing the lower surface of the blade 26 into contact with the flat portion 9a of the container 9. Then, the control unit C drives the motor 22, moving the container 9 towards the motor 22 (arrow d). As a result, the blade 26 slides relative to the flat portion 9a, collecting the paste film 8a that had formed on the flat portion 9a to one side of the container 9 (the side farther from the motor 22), removing it from the flat portion 9a, and stirring the paste 8.

[0022] In Figure 5(b), during the film formation operation, with the container 9 in a position close to the motor 22 (the state in Figure 5(a)), the control unit C raises the blade 26 using the blade lifting unit 28, moving the lower surface of the blade 26 away from the flat portion 9a of the container 9. Next, the control unit C lowers the squeegee 27 using the squeegee lifting unit 29, positioning the lower surface of the blade 26 at a predetermined height (corresponding to the thickness of the paste film 8a) above the flat portion 9a of the container 9. Then, the control unit C drives the motor 22, moving the container 9 to the side away from the motor 22 (arrow e). As a result, the squeegee 27 moves above the flat portion 9a at a predetermined height, and the paste film 8a is formed on the flat portion 9a.

[0023] In Figure 5(c), during the paste application operation, with a paste film 8a formed on the flat portion 9a, the control unit C lowers the heating tool 15, which holds the tip 5 with the bonding head 16, to the dipping position P set on the flat portion 9a where the paste film 8a is formed (arrow f), thereby applying the paste 8 to the tip 5. Once the paste 8 is applied to the tip 5, the control unit C raises the heating tool 15, which holds the tip 5 with the bonding head 16 (arrow g). In the paste supply unit 10, the paste stirring operation (paste stirring process), film formation operation (film formation process), and paste application operation (paste application process) are repeatedly performed in sequence.

[0024] Next, with reference to Figure 6, the effect of the heated chip 5 on the paste film 8a formed on the flat portion 9a of the container 9 will be explained. Figures 6(a) to (d) are enlarged views of the area near the dipping position P on the flat portion 9a where the chip 5, heated by the heater 15a built into the heating tool 15, lands on the paste film 8a.

[0025] Figure 6(b) shows the state in which the tip 5, held by the heating tool 15, lands on the dipping position P (Figure 6(a)) of the paste film 8a formed on the flat portion 9a of the container 9 by the film formation operation, due to the paste adhesion operation. The paste film 8a to which the heated tip 5 lands undergoes a transformation into altered paste 8b due to the volatilization of the solvent contained in the paste 8 caused by the heat.

[0026] Figure 6(c) shows the state in which, during the paste stirring operation, the blade 26 slides relative to the flat portion 9a (arrow h) near the dipping position P where the altered paste 8b was formed, removing the paste film 8a that had formed on the flat portion 9a. In the removal by the blade 26 during the paste stirring operation immediately after the paste application operation, some of the altered paste 8b is not removed and remains on the flat portion 9a.

[0027] Figure 6(d) shows the state after the paste stirring operation, where the squeegee 27 moves relative to the flat area 9a (arrow i) during the film formation operation, forming a paste film 8a on the flat area 9a. Due to the film formation operation, a paste film 8a is also formed on top of the altered paste 8b that remained on the flat area 9a. If the paste attachment operation is performed in this state and the chip 5 is landed on the dipping position P where the altered paste 8b remains, the paste 8 may not adhere properly to the chip 5, and the amount of paste 8 transferred may vary, potentially leading to mounting defects.

[0028] Meanwhile, the altered paste 8b remaining on the flat portion 9a is supplied with solvent contained in the paste 8 from the newly formed paste film 8a, causing a portion of it to soften. If the next paste stirring operation is performed without landing the tip 5 on the dipping position P where the altered paste 8b remains, the sliding blade 26 removes a portion of the softened altered paste 8b. Subsequently, by repeating the film formation operation and paste stirring operation (removal of the softened altered paste 8b) multiple times (for example, 6 times), the remaining altered paste 8b is removed from the dipping position P where the altered paste 8b was formed, and only a normal paste film 8a is formed.

[0029] Next, with reference to Figure 7, a chip mounting method will be described in which paste 8 is applied to a heated chip 5 and mounted onto a substrate 11 in a continuous process. In the paste supply unit 10, multiple dipping positions P1 to P6 are set on the flat portion 9a where a paste film 8a is formed by the film formation operation. The number and positions of the dipping positions P1 to P6 are determined based on the size of the chip 5, the temperature of the heated chip 5, the material of the paste 8, etc. In this example, six dipping positions P1 to P6 are set on the flat portion 9a.

[0030] In the mounting process for mounting the chip 5 onto the substrate 11, first, the pickup tool 13 picks up the chip 5 from the chip supply stage 2 and inverts it (pickup step), and the heating tool 15 receives the chip 5 from the pickup tool 13 (receiving step). Next, the heating tool 15 holding the chip 5 is lowered to one of the dipping positions P1 to P6 on the flat portion 9a where a paste film 8a has been formed by a film formation operation (film formation step), and the paste 8 is attached to the chip (paste attachment step). Then, the heating tool 15 is lowered to the mounting position on the substrate 11, and the chip 5 with the paste 8 attached is mounted onto the substrate 11 (mounting step).

[0031] The chip 5 held by the heating tool 15 is heated by the heater 15a built into the heating tool 15 from the receiving process to the mounting process. In the mounting operation of the chip 5, the pickup process and the mounting process are repeatedly executed, so that the chips 5 held on the adhesive sheet 6 of the chip supply stage 2 are sequentially mounted onto the substrate 11.

[0032] The following describes the paste stirring operation (paste stirring process), film formation operation (film formation process), and paste adhesion operation (paste adhesion process) performed in the paste supply unit 10. In Figure 7, during the first paste adhesion process, the first tip 5 held by the heating tool 15 lands at the first dipping position P1 and paste 8 is attached to it. As a result, altered paste 8b is formed at the first dipping position P1.

[0033] Next, in the paste supply unit 10, a paste stirring process and a film formation process are performed, and a paste film 8a is formed on the flat portion 9a. In the second paste adhesion process, the second tip 5 held by the heating tool 15 lands at the second dipping position P2 and paste 8 is attached to it. In the third paste adhesion process, the third tip 5 held by the heating tool 15 lands at the third dipping position P3 and paste 8 is attached to it.

[0034] Similarly, the paste stirring process, film formation process, and paste adhesion process are repeatedly performed, and in the sixth paste adhesion process, the sixth tip 5 lands at the sixth dipping position P6. Through the repetition of the paste stirring process and film formation process during this time, only a paste film 8a is properly formed at the first dipping position P1. Then, in the seventh paste adhesion process, the seventh tip 5 held by the heating tool 15 returns to the beginning and lands at the first dipping position P1, and paste 8 is adhered to it. In other words, the control unit C uses a dipping position (first dipping position P1) after the film formation operation has been performed a predetermined number of times (6 times).

[0035] Thus, in the chip mounting method of this embodiment, a paste adhesion operation (paste adhesion step) in which paste 8 is attached to the chip 5 and a film formation operation (film formation step) in which a paste film 8a is formed on the flat portion 9a are performed alternately, and a dipping position (second dipping position P2) different from the dipping position (first dipping position P1) used in the previous paste adhesion operation is used.

[0036] In other words, the control unit C, which controls the bonding head 16 and the paste supply unit 10, lowers the heating tool 15 to a dipping position different from the dipping position used in the previous paste application operation (first paste application operation) during the paste application operation (second paste application step). As a result, an appropriate amount of normal paste 8 is applied to the heated chip 5, allowing it to be stably mounted on the substrate 11.

[0037] As described above, the chip mounting apparatus (mounting apparatus 1) of this embodiment lowers the heating tool 15 holding the chip 5 to a dipping position P set on the flat portion 9a where the paste film 8a is formed, thereby adhering the paste 8 to the chip 5, and then lowers the heating tool 15 toward the substrate 11 to mount the chip 5 with the paste 8 attached to it onto the substrate 11.

[0038] In this process, the chip mounting device alternately performs a paste application operation to attach the paste 8 to the chip 5 and a film formation operation to form a paste film 8a on the flat portion 9a. During the paste application operation (second paste application step), a different dipping position (second dipping position P2) is used than the dipping position (first dipping position P1) used in the previous paste application operation (first paste application step). This allows the paste 8 to be applied to the heated chip 5 and mounted on the substrate 11 using a simple configuration. [Industrial applicability]

[0039] The chip mounting apparatus and chip mounting method of the present invention have the advantage of allowing a paste to be applied to a heated chip and mounted onto a substrate with a simple configuration, and are useful in the field of mounting components onto substrates. [Explanation of Symbols]

[0040] 5 chips 8 Paste 8a Paste film 9 containers 9a Flat area 10 Paste supply unit 11 circuit boards 15 Heating Tools 16 Bonding Heads P, P1~P6 Dipping positions

Claims

1. A chip mounting apparatus that lowers a heating tool holding a chip to a dipping position set on a flat portion on which a paste film has been formed, thereby adhering the paste to the chip, and then lowers the heating tool toward a substrate to mount the chip with the paste attached to it onto the substrate, The paste application operation, in which paste is applied to the chip, and the film formation operation, in which a film of the paste is formed on the flat surface, are performed alternately, and a different dipping position from the one used in the previous paste application operation is used during the paste application operation. A chip mounting apparatus that performs the film formation operation including the dipping position that was used once in the paste application operation.

2. A bonding head for moving the aforementioned heating tool, A paste supply unit having a container containing the paste having the flat portion, which performs the film-forming operation and a paste stirring operation in which the film of the paste is collected on one side of the container and removed from the flat portion and the paste is stirred, It comprises at least the bonding head and a control unit for controlling the paste supply unit, The chip mounting apparatus according to claim 1, wherein the control unit lowers the heating tool to a dipping position different from the dipping position used in the previous paste application operation during the paste application operation.

3. The chip mounting apparatus according to claim 2, wherein the dipping position that has been used once is used again after the film formation operation has been performed a predetermined number of times.

4. A method for mounting a chip, comprising lowering a heating tool holding the chip to a dipping position set on a flat portion where a paste film is formed, thereby adhering the paste to the chip, and then lowering the heating tool toward a substrate to mount the chip with the paste attached to it onto the substrate, The paste application operation, in which paste is applied to the chip, and the film formation operation, in which a film of the paste is formed on the flat surface, are performed alternately, and a different dipping position from the one used in the previous paste application operation is used during the paste application operation. A chip mounting method comprising performing the film formation operation including the dipping position that was used once in the paste adhesion operation.

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