JP2017157682A - Component mounting device and mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform alignment of a component and a board with high accuracy, while preventing voids from remaining when mounting a component of large plane size.SOLUTION: A component mounting device 1 includes a mounting tool 10 for suction holding a component 2, and a camera 15 placed directly above the mounting tool 10. The mounting tool 10 includes a base 11 composed of transparent glass, a suction head 12 consisting of a transparent elastic member attached to the lower surface of the base 11, and a transparent plate 16 combining with the base 11 to form a suction path. A camera 15 simultaneously captures a second alignment mark 2a appearing in a region overlapping the suction head 12 in a state where the component 2 is suction held to the lower surface of the suction head 12, and a first alignment mark 5a appearing in a region not overlapping the suction head 12. The mounting tool 10 aligns the component 2 based on the first and second alignment marks 5a, 2a, before pressing the component 2 against the board 3 and mounting thereon.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a component mounting apparatus and mounting method, and more particularly to a component mounting apparatus and mounting method suitable for mounting electronic components such as semiconductor IC chips.

  In recent years, portable electronic devices such as smartphones and tablet PCs are widely used. In these portable electronic devices, an IC-embedded substrate that integrates many functions is mounted in order to reduce the size and increase the functionality. An IC-embedded substrate is a module component in which a bare chip of a semiconductor IC ground very thin is embedded in the substrate, and passive components such as a capacitor, an inductor, a thermistor, and a resistor are surface-mounted on the surface of the substrate. According to this IC-embedded substrate, various power supply circuits and a plurality of wireless communication functions can be modularized, and a small, thin and highly functional portable electronic device can be realized.

  In manufacturing an IC-embedded substrate, a mounting apparatus for surface-mounting an IC chip on the substrate is used. For example, Patent Document 1 discloses an apparatus for mounting an IC chip with a first recognition mark on a substrate disposed below and provided with a second recognition mark for alignment with the IC chip. It is disclosed. This apparatus has optical path direction conversion means such as a prism in a tool that holds an IC chip from the upper surface side, and recognition means such as a CCD camera on the side of the tool. The optical paths for reading the positions of the first and second recognition marks are converted laterally by the optical path direction conversion means and guided to the recognition means. According to this apparatus, it is possible to directly read both the first and second recognition marks, and the IC chip can be aligned and bonded to the lower substrate with high accuracy. However, it can be easily held by suction, and highly accurate positioning and joining are possible.

International Publication No. 2003/041478 Pamphlet

  However, the above-described conventional mounting apparatus needs to be provided with an optical path changing unit, and there is a problem that the configuration becomes complicated and the component cost increases.

  Further, when mounting a thin IC chip having a large planar size in a conventional mounting apparatus, there is a problem that bubbles (voids) are likely to remain between the lower surface of the IC chip and the substrate surface. The remaining bubbles are thermally expanded in the subsequent heat treatment process, and there is a risk of causing peeling or breakage of the interface.

  As a method of reducing voids remaining when an IC chip is mounted, there is a method in which a low-viscosity uncured resin is applied in advance to a mounting position of the IC chip and the IC chip is mounted thereon. Since the uncured resin is familiar with the IC chip and fills the gap with the substrate surface, even when a thin IC chip having a large planar size is warped, bubbles are hardly left. In addition, since the uncured resin has a low viscosity even at room temperature, it is not necessary to heat the entire substrate and the alignment mark is not oxidized. However, due to the low viscosity, there is a problem that the IC chip moves and the positional accuracy deteriorates after the IC chip is mounted until the resin is cured.

  As another method for reducing residual voids when mounting an IC chip, a semi-cured resin sheet is pasted in advance on the IC chip mounting position in the absence of air bubbles, and the IC chip is mounted on the semi-cured resin sheet. In this method, it is necessary to heat the resin in order to reduce the viscosity of the semi-cured resin when the IC chip is mounted. However, in the method in which the IC chip is picked up by a mounting head that has been heated in advance and the resin is heated by pressing the IC chip against a semi-cured resin, the holding time of the IC chip becomes long and the mounting time becomes long. There is also a method of heating the entire board, but the alignment mark placed near the mounting position is gradually oxidized to improve mounting accuracy, and mounting is performed when mounting multiple IC chips on the collective board in order. There is a problem that the position cannot be recognized when the accuracy is gradually deteriorated and the oxidation of the alignment mark is advanced.

  Therefore, an object of the present invention is to mount components that can accurately align components such as an IC chip and a substrate, and prevent residual voids even when mounting components with a large planar size. It is to provide an apparatus and method.

  In order to solve the above problems, a component mounting apparatus according to the present invention mounts the component on the substrate with reference to a first alignment mark provided on the substrate and a second alignment mark provided on the component. A mounting tool for sucking and holding the component, a lifting mechanism for lifting and lowering the mounting tool, and a camera disposed above the mounting tool, the mounting tool being a base made of transparent glass A suction head made of a transparent elastic member attached to the lower surface of the base, and a transparent plate disposed above the base and forming a suction path by a combination with the base. In a state where the component is sucked and held on the lower surface of the suction head, the second alignment mark that can be seen in an area overlapping the suction head; The first alignment mark that appears in an area that does not overlap the suction head is photographed simultaneously, and the mounting tool aligns the component based on the first and second alignment marks, and then places the component on the substrate. The component is pressed and mounted.

  The component mounting method according to the present invention includes a step of attaching a semi-cured resin sheet on a substrate provided with a first alignment mark, a second alignment mark provided on the component, and the substrate. The step of mounting the component on the substrate with reference to the first alignment mark, and the step of curing the resin sheet by heating the substrate, wherein the step of mounting the component is transparent elastic A step of sucking and holding the component using a suction head made of a member; and the second alignment mark that is visible in a region overlapping with the suction head in a state where the component is sucked and held on the lower surface of the suction head; A step of simultaneously photographing with the camera the first alignment mark that appears to pass through the resin sheet in a region that does not overlap the suction head; After serial to align the first and the component based on the second alignment mark, characterized in that it implements against the component on the resin sheet.

  According to the present invention, the in-plane of a component can be pressurized as uniformly as possible, thereby preventing voids from remaining between the lower surface of the component and the upper surface of the substrate.

  In the present invention, the suction head is preferably made of a transparent silicone rubber. Since the transparent silicone rubber has sufficient transparency and heat resistance and is easy to process, a high-quality and highly reliable suction head can be configured.

  In the present invention, it is preferable that an adhesion preventing film is formed on the lower surface of the suction head. The surface of the suction head made of silicone rubber has adhesiveness, and has a property that it is difficult to peel off when the flat surface of the component sticks to the suction head. However, if there is an anti-adhesion film, the suction head can be easily separated from the component when the suction is lifted by lifting the suction head after pressing the component against the substrate. Therefore, the component is not displaced, and the component mounting position accuracy can be improved.

  In this invention, it is preferable that the said suction head has a suction hole, and the said suction hole is offset-positioned with respect to the center part of the said lower surface. According to this configuration, when the component is pressed and mounted on the substrate, the central portion can be surely pressed, thereby avoiding a situation in which bubbles remain on the back side of the component.

  In the present invention, the component is a semiconductor IC chip having electrode pads, and the semiconductor IC chip is held by a mounting tool with the electrode pads facing upward, and the second alignment mark is An electrode pad is preferred. When a semiconductor IC chip is mounted face-up on a substrate, voids are likely to remain between the lower surface of the chip and the upper surface of the substrate. However, according to the present invention, the surface of the semiconductor IC chip is made as uniform as possible. Pressure can be applied, and bubbles can be prevented from remaining. Further, by using an electrode pad as the second alignment mark, a dedicated alignment mark can be omitted.

  According to the present invention, a component mounting apparatus capable of accurately aligning a component such as an IC chip and a substrate and preventing voids from remaining even when a component having a large planar size is mounted. A method can be provided.

FIG. 1 is a schematic side view showing the configuration of the component mounting apparatus according to the first embodiment of the present invention. FIG. 2 is a schematic plan view showing an IC chip photographed by a camera and a layout around the IC chip. FIG. 3 is a flowchart for explaining a component mounting method using the component mounting apparatus. FIG. 4 is a schematic side view showing the configuration of the component mounting apparatus, and particularly shows a state where the mounting tool is lowered. FIG. 5 is a schematic side view showing the configuration of the component mounting apparatus, and particularly shows a state where the mounting tool is raised after the IC chip is mounted.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic side view showing the configuration of the component mounting apparatus according to the first embodiment of the present invention.

  As shown in FIG. 1, the component mounting apparatus 1 includes a mounting tool 10 that sucks and holds an IC chip 2 that is a mounting component, a frame 13 that supports the mounting tool 10, and an elevation that moves the mounting tool 10 up and down together with the frame 13. A mechanism 14 and a camera 15 arranged above the mounting tool 10, particularly just above are provided.

  The mounting tool 10 includes a base 11 made of transparent glass, a suction head 12 attached to the lower surface of the base 11, and a transparent plate 16 that is disposed above the base 11 and forms a suction path in combination with the base 11. Have. The mounting tool 10 is attached to the lower end of the frame 13 and is driven up and down together with the frame 13 when the IC chip 2 is mounted. Although not particularly limited, it is preferable to use a voice coil motor or an air cylinder as the lifting mechanism 14.

  On the other hand, the camera 15 is a CCD camera, for example, and is fixed to a certain position (height) without being fixed to the frame 13. Since the camera 15 does not move up and down together with the mounting tool 10, the IC chip 2 and the substrate 3 can be photographed stably.

  The substrate 3 on which the IC chip 2 is mounted has an insulating support substrate 4, a conductor layer 5 formed on the upper surface of the support substrate 4, and an insulating layer 6 that covers the entire surface of the conductor layer 5. The insulating layer 6 is provided to insulate and isolate the conductor layer 5 on the substrate 3 and the IC chip 2. The substrate 3 is a substrate in the middle of processing the IC-embedded substrate, and the insulating layer 6 is a transparent layer made of an uncured (including semi-cured) resin sheet. An alignment mark (first alignment mark) 5 a on the substrate 3 is a negative pattern formed on the conductor layer 5 and is visible through the insulating layer 6.

  The suction head 12 is made of a transparent elastic member and constitutes a convex portion of the mounting tool 10. As the material of the suction head 12, it is preferable to use a transparent silicone rubber that has sufficient transparency and heat resistance and is easy to process. When the suction head 12 has elasticity, when the IC chip 2 is mounted on the substrate 3 and pressed, the inside of the IC chip 2 can be pressed as uniformly as possible, whereby the lower surface of the IC chip 2 and the substrate can be pressed. It is possible to prevent a void from remaining between the upper surface of 3.

  In order to hold the IC chip 2 securely, the plane size of the lower surface of the suction head 2 is preferably larger than the plane size of the IC chip 2. However, the planar size of the suction head 12 is preferably smaller than the planar size of the base 11 in order to prevent interference with other IC chips 2 mounted in the adjacent mounting region. Further, in order to sufficiently exhibit the elasticity of the suction head 12, the suction head 12 needs to have a certain thickness, and is required to be at least thicker than the IC chip 2. Furthermore, the base 11 needs to have a sufficient thickness to withstand the load applied during mounting.

  In addition, since the camera 15 needs to be disposed immediately above the mounting tool 10, it is necessary to secure a certain size of the planar size of the base 11 in accordance with the space necessary for installation of the camera 15. Therefore, it is preferable that the planar size of the base 10 is sufficiently larger than the planar size of the IC chip 2.

  In the present embodiment, it is preferable that an anti-adhesion film 12 b is formed on the lower surface of the suction head 12 that contacts the IC chip 2. The surface of the suction head 12 made of silicone rubber has adhesiveness (tackiness), and has a property that the flat surface of the IC chip 2 is difficult to peel off when sticking to the suction head 12. However, when there is the anti-adhesion film 12b, the suction head 12 can be easily separated from the IC chip 2 when the suction head 12 is lifted by releasing the suction after pressing the IC chip 2 against the substrate. Therefore, the IC chip 2 is not displaced and the mounting accuracy of the IC chip 2 can be improved. The anti-adhesion film may be, for example, a modified film such as organopolysiloxane formed on the surface of silicone rubber. The anti-adhesion film may be a PET film, and is preferably a PET film having an antistatic treatment on the surface.

  In the present embodiment, the mounting tool 10 has a suction hole 10 a, and the suction hole 10 a is offset with respect to the central portion of the lower surface of the suction head 12. The suction hole 10 a is a connection hole between the suction hole 11 a on the base 11 side and the suction hole 12 a on the suction head 12 side, and penetrates the base 11 and the suction head 12.

  A transparent plate 16 made of glass or resin is provided above the base 11, and the space between the base 11 and the transparent plate 16 is surrounded by a sealing wall, thereby ensuring a sealed space. ing. An air inlet 12c is provided in a part of the sealing wall, and the sealed space is used as a suction path. By vacuuming from the air inlet 12c, the IC chip 2 can be adsorbed to the lower surface of the adsorption head 12. it can.

  In the present embodiment, since the base 11, the suction head 12, and the transparent plate 16 that constitute the mounting tool 10 are all transparent members, the imaging region of the camera 15 is not blocked by the constituent members of the mounting tool 10. Therefore, the camera 15 takes an image of the electrode pad 2a on the IC chip 2 that can be seen through the base 11, the transparent plate 16, and the suction head 12 as an alignment mark (second alignment mark) in an area overlapping the suction head 12. Can do. Further, the camera 15 can photograph the alignment mark 5a on the substrate 3 that is transmitted through the base 11 and the transparent plate 16 in a region that does not overlap with the suction head 12 and that further appears through the transparent resin constituting the insulating layer 6. .

  The IC chip 2 is sucked and held by the mounting tool 10 with the electrode pads 2a facing upward. Then, the electrode pad 2a of the IC chip 2 is photographed by the camera 15 as an alignment mark, whereby the holding position of the IC chip 2 is recognized.

  FIG. 2 is a schematic plan view showing the IC chip 2 photographed by the camera 15 and its surrounding layout.

  As shown in FIG. 2, the alignment mark of the IC chip 2 is preferably two electrode pads 2am positioned diagonally to each other among the plurality of electrode pads 2a arranged on the main surface of the IC chip 2. . As the alignment marks on the substrate 3 side, two alignment marks 5a that are positioned diagonally to each other and orthogonal to the alignment mark on the IC chip 2 side can be used. In addition, the alignment mark in a figure is attached with the dashed line of the cross. The alignment mark 5a may be a positive pattern of the conductor layer 5 or a negative pattern obtained by removing a part of the conductor layer 5.

  As shown in FIG. 2, four suction holes 12a are provided and are laid out so as to have a symmetrical positional relationship when viewed from the center of the rectangular planar substrate. That is, the suction hole 12 a penetrating the suction head 12 is provided at a position offset from the central portion of the lower surface of the suction head 12. According to this configuration, when the IC chip 2 is pressed and mounted on the substrate 3, the central portion of the IC chip 2 can be reliably pressed, thereby avoiding a situation where bubbles remain on the back side of the IC chip 2. can do.

  In the present embodiment, the two alignment marks 5a, 5a on the substrate 3 side are arranged outside the suction head 12 in plan view, and the distance between the two alignment marks 5a, 5a is the same direction of the suction head 12 Wider than the width of. Furthermore, the position of the alignment mark 5a is laid out at a certain distance so as not to overlap the outer periphery of the suction head 12 when viewed from the camera 15. Therefore, the camera 15 can visually recognize the two alignment marks 5a and 5a on the substrate 3 side without being blocked by the IC chip 2. Further, it is possible to avoid a situation in which the alignment mark 5a cannot be correctly recognized because the alignment mark 5a overlaps the outer periphery of the suction head 12.

  In this embodiment, a plurality of alignment marks (electrode pads 2a) on the IC chip 2 side and a plurality of alignment marks 5a on the substrate 3 side are photographed simultaneously by one camera 15, so that the position of the IC chip 2 with respect to the substrate 3 is determined. Can be grasped accurately.

  FIG. 3 is a flowchart for explaining a component mounting method using the component mounting apparatus 1.

  As shown in FIG. 3, in mounting the IC chip 2, first, the support substrate 4 on which the alignment mark 5 a is formed is prepared, and a semi-cured resin sheet is pasted on the support substrate 4 to form the insulating layer 6 ( Step S11). In addition, the board | substrate 3 shown in FIG. 1 has the insulating layer 6 formed on the support substrate 4 provided with the alignment mark 5a.

  Next, the IC chip 2 is sucked and held by the mounting tool 10 (step S12). The IC chip 2 is conveyed directly below the mounting tool 10 by a transport device (not shown), and the mounting tool 10 is lowered to attract the IC chip 2 on the transport device to the lower surface of the suction head 12 and lift it. And the suction holding of the IC chip 2 is completed when the transport device returns to the retracted position.

  Next, the position of the electrode pad 2am on the IC chip 2 that can be seen through the transparent plate 16, the base 11 and the suction head 12 of the mounting tool 10 is recognized as the position of the alignment mark, and the base 11 and the resin of the mounting tool 10 are recognized. The position of the alignment mark 5a of the substrate 3 that is seen through the sheet (insulating layer 6) is recognized (step S13).

  Next, the IC chip 2 is aligned with the substrate 3 (step S14). In the alignment, it is preferable to move the substrate 3 side in the plane direction, but the IC chip 2 side, that is, the mounting tool 10 side may be moved in the plane direction.

  Next, the suction head 12 is lowered, and the IC chip 2 is mounted on the upper surface of the substrate 3 (specifically, the upper surface of the insulating layer 6 on the support substrate 4) and pressed with a certain load, and the back surface of the IC chip 2 ( Air bubbles present on the lower surface are removed (step S15). FIG. 4 shows a state where the mounting tool 10 is lowered. Further, in this state, the substrate 3 is heated to 50 to 100 ° C. (step S16). This heating can be performed by a heater 7 a provided on the stage 7 that supports the substrate 3. Although the back surface of the IC chip 2 in FIG. 4 is a flat surface on which no electrode pattern is formed, an IC chip on which the electrode pattern is formed on the back surface can be handled in the same manner.

  Thus, in the present embodiment, the IC chip 2 is picked up by the suction head 12 and positioned based on the alignment mark 5a, and then pressed onto the substrate 3. At the same time, the substrate 3 is locally heated to cure the semi-cured resin sheet. When the heater 7a is directly under the IC chip 2, the temperature rises around the position of the IC chip 2, so the range of oxidation of the alignment mark 5a is limited. Further, if the alignment mark 5a for positioning the mounted IC chip 2 is used, there is no problem even if the visibility deteriorates due to oxidation.

  Next, the suction is released and the mounting tool 10 is moved upward to leave the IC chip 2 on the mounting substrate (step S17). FIG. 5 shows a state where the mounting tool 10 is raised after the IC chip 2 is mounted.

  Thus, the mounting of one IC chip 2 is completed. In order to mount a plurality of IC chips, the substrate 3 is moved together with the stage 7 to relatively move the mounting tool 10 to the next mounting position, and then the above steps are performed.

  As described above, in the component mounting apparatus 1 according to the present embodiment, since the mounting tool 10 is entirely made of a transparent member, the IC chip 2 is mounted using the camera 15 disposed above the mounting tool 10. The state can be grasped accurately. In particular, the alignment mark (land) on the IC chip 2 can be recognized through the base 11 and the suction head 12 of the mounting tool 10, and the substrate 3 can be seen through a region that does not overlap the suction head 12 of the base 11. The upper alignment mark can be recognized.

  In the present embodiment, since the contact surface of the mounting tool 10 with the IC chip 2 is made of transparent silicone rubber, it is possible to prevent air bubbles from being trapped on the back surface of the IC chip 2 when the IC chip 2 is mounted. . Therefore, a highly reliable mounting apparatus and mounting method can be provided.

  Furthermore, in the present embodiment, since the suction hole penetrating the suction head 12 is provided in a region excluding the central portion of the main surface, when the IC chip 2 is pressed onto the substrate 3 and mounted, The center part of 2 can be pushed reliably, and the situation where a bubble remains on the back surface side of the IC chip 2 can be avoided.

  Further, according to the present embodiment, since the adhesion preventing film for reducing the adhesiveness is applied to the contact surface of the suction head 12 with the IC chip 2, the IC chip 2 is mounted after the IC chip 2 is mounted on the substrate. When the mounting tool 10 is pulled apart while leaving the substrate on the substrate, the IC chip 2 can be easily separated. In addition, since the coating is not performed on the upper surface of the suction head 12 facing the base 11 and the tackiness is maintained, the integrity of the base 11 and the suction head 12 can be improved.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. Needless to say, it is included in the range.

  For example, in the above embodiment, an IC chip is used as a mounting component. However, the present invention is not limited to an IC chip, and includes various components mounted on a substrate, such as passive elements and optical elements.

  Further, the material of the suction head is not limited to transparent silicone rubber, and any material may be used as long as it is a transparent elastic member. It is also possible to omit the anti-adhesion film on the lower surface of the suction head.

  Moreover, in the said embodiment, although the number of the suction holes of a mounting tool is four, the number is not specifically limited. In addition, the suction hole is offset with respect to the central portion of the suction surface of the mounting head, but may not necessarily be offset, and may be provided at the central portion of the suction surface of the mounting head.

DESCRIPTION OF SYMBOLS 1 Component mounting apparatus 2 IC chip 2a Electrode pad 2am Electrode pad (alignment mark)
3 Substrate 4 Support substrate 5 Conductor layer 5a Alignment mark 6 Insulating layer 7 Stage 7a Heater 10 Mounting tool 10a Suction hole 11 Base 11a Suction hole 12 Suction head 12a Suction hole 12b Adhesion prevention film 12c Suction port 13 Frame 14 Elevating mechanism 15 Camera 16 Transparent plate

Claims (10)

A component mounting apparatus that mounts the component on the substrate with reference to a first alignment mark provided on the substrate and a second alignment mark provided on the component,
A mounting tool for sucking and holding the component;
A lifting mechanism for lifting and lowering the mounting tool;
A camera disposed above the mounting tool,
The implementation tool is:
A base made of transparent glass,
A suction head made of a transparent elastic member attached to the lower surface of the base;
A transparent plate disposed above the base and forming a suction path in combination with the base;
The camera includes the second alignment mark that appears in a region that overlaps the suction head and the first alignment that appears in a region that does not overlap the suction head in a state where the component is sucked and held on the lower surface of the suction head. Shoot the mark at the same time,
The mounting tool aligns the component based on the first and second alignment marks, and then mounts the component by pressing the component onto the substrate.   The component mounting apparatus according to claim 1, wherein the suction head is made of transparent silicone rubber.   The component mounting apparatus according to claim 2, wherein an adhesion preventing film is formed on the lower surface of the suction head.   4. The component mounting apparatus according to claim 1, wherein the suction head has a suction hole, and the suction hole is offset from a center portion of the lower surface. The component is a semiconductor IC chip having an electrode pad,
The semiconductor IC chip is sucked and held by a mounting tool in a face-up state with the electrode pads facing upward,
The component mounting apparatus according to claim 1, wherein the second alignment mark is the electrode pad. Attaching a semi-cured resin sheet on the substrate provided with the first alignment mark;
Mounting the component on the substrate with reference to a second alignment mark provided on the component and the first alignment mark provided on the substrate;
Heating the substrate and curing the resin sheet,
The step of mounting the component includes
Sucking and holding the part using a suction head made of a transparent elastic member;
In a state where the component is sucked and held on the lower surface of the suction head, the second alignment mark that appears in a region overlapping with the suction head and the second alignment mark that appears through the resin sheet in a region that does not overlap with the suction head. A step of simultaneously photographing one alignment mark with a camera;
And a step of mounting the component by pressing the component onto the resin sheet after aligning the component based on the first and second alignment marks.   The component mounting method according to claim 6, wherein the suction head is made of transparent silicone rubber.   The component mounting method according to claim 7, wherein an adhesion preventing film is formed on the lower surface of the suction head.   The component mounting method according to claim 6, wherein the suction head has a suction hole, and the suction hole is offset from a center portion of the lower surface. The component is a semiconductor IC chip having an electrode pad,
The semiconductor IC chip is sucked and held by a mounting tool in a face-up state with the electrode pads facing upward,
The component mounting method according to claim 6, wherein the second alignment mark is the electrode pad.

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