JP2012074558A - Conductive ball mounting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive ball mounting device with excellent ball mounting accuracy: by providing a projecting part on an arrangement mask corresponding to a concavity of a substrate to enable positioning for an electrode on the substrate by an open hole on the arrangement mask; and by preventing unnecessary supply of the conductive ball.SOLUTION: A conductive ball mounting device adopts a method characterized in that: first, the conductive ball mounting device comprises an arrangement mask 3 provided with an open hole 31 corresponding to an electrode 22, and ball mounting means for supplying a conductive ball on the arrangement mask, where the conductive ball is mounted on the electrode on a substrate 2 through the open hole on the arrangement mask; second, the substrate has a concavity 21 formed so that the electrode is installed on the bottom of the concavity and so that the depth from the upper part of the electrode to the top face (surface excluding the concavity) of the substrate is larger than a diameter of the mounted conductive ball; and third, the arrangement mask has a projecting part 32, which projects corresponding to the concavity on the substrate, on the face opposed to the substrate.

Description

  The present invention relates to a conductive ball mounting device for mounting a conductive ball on an electrode of a substrate having a recess larger than the diameter of the conductive ball provided with an electrode at the bottom and having a depth up to the top of the electrode. It is about.

  As a conventional conductive ball mounting apparatus, as disclosed in Patent Document 1, there is an apparatus for mounting a conductive ball on an electrode provided on the surface of a flat substrate using a flat array mask. . However, in recent years, there has been an increasing demand for a substrate (embedded substrate) provided with a recess for accommodating an electronic component to be mounted in order to cope with the reduction in size and thickness of the electronic component and to eliminate the protrusion. Yes.

  As shown in FIG. 4, with respect to the electrode 22 provided on the bottom 23 of the recess 21 formed on the Embedded substrate 20, the conductive ball 10 having a size that can be completely accommodated in the recess 21, in other words, Then, when the conductive ball 10 having a ball diameter (D) smaller than the depth (L) from the surface 24 other than the recess 21 to the upper portion of the electrode 22 is mounted with the flat mask 30, the conductive ball 10 is When passing through the through-hole 31 of the flat mask 30, it rolls between the flat mask 30 and the upper part of the electrode 22, and the problem is that more than the necessary number of conductive balls 10 are supplied to the recess 21. was there.

Japanese Patent Laid-Open No. 2008-153336

  According to the present invention, by providing a protruding portion that protrudes from the arrangement mask in correspondence with the depression of the substrate on which the electrode is formed, positioning by the through hole of the arrangement mask can be performed with respect to the electrode, and is unnecessary. An object of the present invention is to provide a conductive ball mounting device that prevents the supply of conductive balls and has high ball mounting accuracy.

In order to solve the above-mentioned problem, the first invention employs the following means for the conductive ball mounting apparatus. First, there is provided an array mask in which through holes are provided in accordance with electrodes arranged in a predetermined pattern on a substrate, and ball mounting means for supplying conductive balls on the array mask, and the through holes of the array mask are provided. A conductive ball mounting device for mounting a conductive ball on an electrode on a substrate through a hole.
Second, the substrate is provided with a recess, an electrode is provided at the bottom of the recess, and a depth of the conductive ball mounted from the top of the electrode to the upper surface of the substrate (the surface other than the recess) is mounted. It has a recess larger than the diameter.
Third, the array mask has a convex portion that protrudes corresponding to the concave portion of the substrate on a surface facing the substrate.

2nd invention is the mounting apparatus of the conductive ball which added the following means to 1st invention.
First, the protruding amount of the convex portion of the array mask is provided to be larger than the depressed amount of the concave portion of the substrate.
Second, moving means for relatively approaching and separating the array mask and the substrate is provided.
Third, ball mounting by the ball mounting means is performed in a state where the lower surface of the convex portion and the bottom surface of the concave portion are in close contact with each other.

A third invention is a conductive ball mounting device in which the following means is added to the ball mounting means in the first or second invention.
First, the ball mounting means includes a ball holding means for adsorbing a conductive ball by a ball adsorber provided on a lower surface of a casing connected to a vacuum source, and a movement for moving the ball holding means on the array mask. Means.
Second, the moving means moves the ball holding means to a predetermined position above the arrangement mask.
Thirdly, the conductive balls adsorbed by the ball holding means are supplied onto the arrangement mask by releasing the connection between the casing and the vacuum source.

  The conductive ball mounting apparatus according to the present invention positions a conductive ball by a through-hole of an array mask having a convex portion protruding corresponding to the concave portion of the substrate, even on a substrate having an electrode provided in the concave portion. As a result, the ball mounting accuracy could be improved.

  Although it is an effect of the second invention, a state in which the protruding amount of the convex portion of the array mask is set larger than the depressed amount of the concave portion of the substrate, and the lower surface of the convex portion of the array mask and the bottom surface of the concave portion of the substrate are in close contact with each other Then, by mounting the ball by the ball mounting means, the conductive ball can be positioned more reliably by the array mask on the bottom surface of the concave portion of the substrate, and the conductive ball is disposed between the array mask and the upper portion of the electrode. Therefore, the conductive ball mounting apparatus can prevent unnecessary supply of the conductive balls and can further improve the ball mounting accuracy.

  Although it is the effect of 3rd invention, it became the conductive ball mounting apparatus which can supply and collect | recover a conductive ball by one ball mounting means.

Schematic plan view showing an embodiment of a conductive ball mounting apparatus according to the present invention. Front schematic diagram Explanatory drawing which shows the ball mounting state in the mounting apparatus of a conductive ball Explanatory drawing which shows the example mounted with a flat mask on the substrate which has an electrode in a crevice

  Hereinafter, embodiments of the present invention will be described together with examples according to the drawings. FIG. 1 is a schematic plan view showing an embodiment of a conductive ball mounting apparatus according to the present invention, FIG. 2 is a schematic front view thereof, and FIG. 3 is a ball mounting in the conductive ball mounting apparatus. It is explanatory drawing which shows a state. The mounting device in the embodiment is a solder ball mounting device in which the conductive ball is the solder ball 1 and the mounted object on which the solder ball 1 is mounted is the substrate 2 such as an electronic circuit board or a ceramic substrate.

  The substrate 2 is an embedded substrate 20 (hereinafter simply referred to as a substrate 2) in which a recess 21 for accommodating an electronic component to be mounted is formed in order to cope with the downsizing and thinning of electronic components and to eliminate protrusions. ) Is used. The recesses 21 of the substrate 2 are provided with electrodes 22 in a predetermined pattern arrangement. A solder ball 1 as a conductive ball is mounted on the electrode 22.

  As shown in FIGS. 1 and 2, the solder ball mounting apparatus generally has a board delivery section 5 for loading, a ball mounting section 6, and a board delivery section 7 for unloading. The conductive ball mounting apparatus according to the present invention relates to the ball mounting portion 6.

  The carry-in substrate delivery unit 5 includes a carry-in stage 51 and a carry-in pick and placer 52. The carry-in stage 51 and the carry-in pick and placer 52 have an X drive mechanism. The substrate 2 carried in at the carry-in stage 51 is held by the carry-in pick & placer 52, carried in the X direction (right side in FIG. 2), and placed on the mounting stage 61.

  The carry-out substrate delivery unit 7 includes a carry-out stage 71 and a carry-out pick and placer 72. The carry-out stage 71 and the carry-out pick and placer 72 have an X drive mechanism. The unloading pick and placer 72 holds the substrate 2 from the mounting stage 61, moves the substrate 2 onto the unloading stage 71, and unloads the substrate 2 to the right in FIG. 2 by the unloading stage 71.

  As shown in FIG. 2, the ball mounting unit 6 includes an array mask 3, a ball cup 4 serving as a ball mounting means for supplying the solder balls 1 onto the array mask 3, and a mounting stage 61 on which the substrate 2 is mounted. And have.

  As shown in the upper part of FIG. 3, the ball cup 4 is provided with a ball adsorber 42 on the lower surface of the casing 46 (inside the ball cup 4). The ball cup 4 is connected to a vacuum source by a casing 46 and adsorbs the solder ball 1 to the ball adsorbent 42 by vacuum suction. The ball cup 4 is provided with moving means for moving the ball cup 4 in the XYZ directions on the array mask 3. In FIG. 1, reference numeral 47 is a ball cup X drive mechanism, 48 is a ball cup Y drive mechanism, and 49 is a ball cup Z drive mechanism. The ball mounting means is not limited to the ball cup type, and any other known ball mounting means may be used as long as it is a mask transfer type ball mounting means.

  The ball cup 4 has a space inside, a lower end surface serving as an opening 41, and a ball adsorbing body 42 that adsorbs the solder balls 1 is provided in the internal space (the lower surface of the casing 46). And a lower space 44. The ball adsorbent 42 is made of a metal mesh such as a stainless mesh that does not allow the solder ball 1 to pass through and allows gas to pass through.

  In the embodiment, the ball cup 4 has a rectangular shape provided in parallel as shown in FIG. It is decided in consideration. For example, the opening 41 at the lower end may be circular. Although four ball cups 4 are shown in FIG. 1, in the embodiment, eight ball cups 4 are arranged.

  The upper space 43 of the ball cup 4 is connected to a vacuum source by a suction passage 45 via an electromagnetic on-off valve as a vacuum switching means and a regulator capable of adjusting the pressure and flow rate of gas, and between the array mask 3 A gas flow path as shown by an arrow in FIG. 3 is formed.

  Incidentally, by opening an electromagnetic on-off valve as a vacuum switching means for switching ON / OFF of the suction state in the ball cup 4 by the vacuum source, the suction state in the ball cup 4 is turned ON and the solder ball 1 is moved to the ball adsorber 42. And the electromagnetic ball is closed, and the suction state in the ball cup 4 is turned off to drop the solder ball 1 adsorbed on the ball adsorbent 42, so that the solder ball 1 passes through the array mask 3 to the substrate. It is mounted on the second electrode 22.

  The ball cup 4 and the ball adsorber 42 are made of a conductive material and are grounded by a ground. This prevents the electrostatically charged solder ball 1 from adhering to the inner surface of the ball cup 4 or the ball adsorbent 42 when the suction state is OFF. Further, a vibrator for applying minute vibrations to the ball cup 4 is attached to the outside of the ball cup 4. The vibrator vibrates at least when the suction state in the ball cup 4 is OFF and is attached to the ball cup 4. Vibration is transmitted to the ball adsorbent 42 to promote the fall of the solder ball 1.

  Note that the diameter of the solder ball 1 may be larger than the lower end of the ball cup 4 and the upper surface of the array mask 3 as long as a predetermined gas flow can be obtained during the ball suction operation.

  As shown in FIG. 3, the array mask 3 has a convex portion 32 that protrudes corresponding to the concave portion 21 of the substrate 2 on the surface facing the substrate 2 (the lower surface of the array mask 3). The protruding amount E of the convex portion 32 of the array mask 3 is set to be larger than the depressed amount C of the concave portion 21 of the substrate 2 (E> C). Thereby, the lower surface of the convex part 32 of the arrangement mask 3 can be brought into close contact with the bottom surface of the concave part 21 of the substrate 2, and as a result, the engagement between the arrangement mask 3 and the solder ball 1 is ensured. Accuracy can be improved.

  As shown in FIG. 3, the width of the convex portion 32 of the array mask 3 is set with a gap A so as to be slightly smaller than the width of the concave portion 21 of the substrate 2. This is because, after the solder ball 1 is mounted, the mounting stage 61 is driven to relatively finely move the substrate 2 and the array mask 3 in the XY directions, so that the solder ball 1 is seated on the electrode 22 during the centering operation. This is to take the transfer fee. That is, a play is provided for performing centering after the ball is mounted.

  On the lower surface of the convex portion 32 of the array mask 3, a digging 33 for flux escape is provided. The digging 33 is for preventing the flux extruded by the solder balls 1 mounted on the electrodes 22 from adhering to the lower surface of the array mask 3.

  The mounting stage 61 present in the ball mounting portion 6 is mounted with the substrate 2 and serves as a moving means for relatively approaching and separating the substrate 2 and the array mask 3 in the present invention. The mounting stage 61 has an XYZθ drive mechanism.

  The operation of the embodiment will be described below. First, as a pre-process for transferring the substrate 2 to the ball mounting portion (mounting stage 61), the flux is applied in advance to the ball mounting location on the substrate 2 by the flux applying means provided upstream of the carry-in stage 51. .

  When the substrate 2 is conveyed to a predetermined position by the carry-in stage 51, the carry-in pick & placer 52 sucks and holds the substrate 2 and drives the X to move the substrate 2 from the carry-in stage 51 onto the mounting stage 61, and Positioning is performed by operating the XYZθ drive mechanism of the mounting stage 61 so that 2 is placed at a predetermined position. When the substrate 2 is transferred to the mounting stage 61, the substrate 2 is placed on the mounting stage 61, and the alignment mask 3 is disposed on the substrate 2.

  While positioning so that the positions of the through-holes 31 of the array mask 3 and the electrodes 22 of the substrate 2 are aligned, the mounting stage 61 is Z-driven so that the array mask 3 and the substrate 2 are brought into close contact with each other. In the embodiment, the flux is not adhered to the arrangement mask 3 by the flux escape digging 33 of the arrangement mask 3, so that the arrangement mask 3 and the substrate 2 are in contact with each other.

  Next, an electromagnetic on-off valve as a vacuum switching means is opened to turn on the suction state in the ball cup 4, and then the XYZ drive is performed by the moving means, so that the ball cup 4 is first mounted, that is, the convex portion of the array mask 3 32 is moved upward. When the suction state in the ball cup 4 is turned ON, a gas flow path indicated by an arrow in FIG. 3 is formed between the ball cup 4 and the array mask 3. With this suction force, the solder ball 1 existing below the ball cup 4 floats and is attracted to the ball adsorbing body 42. This state is a state in which the ball cup 4 is movable. When the suction state is OFF, the ball cup 4 is not moved.

  After the ball cup 4 has moved to the initial mounting position, the electromagnetic on-off valve is closed to turn off the suction state in the ball cup 4 and vibrate the vibrator. When the suction is stopped, the ball cup 4 is released to the atmosphere, so that the solder ball 1 attached to the ball adsorbent 42 falls, enters the through hole 31 of the array mask 3, and is mounted on the substrate 2. The solder ball 1 is dropped into the through hole 31, that is, the suction state is repeatedly turned ON (suction) and OFF (stop) several times to ensure mounting on the substrate 2, and the vibrator opens and closes the electromagnetic on-off valve. At the same time, the vibration is repeatedly stopped and generated.

  After the mounting operation of the solder ball 1, the mounting stage 61 is driven to relatively finely move the substrate 2 and the array mask 3 in the XY directions, so that the solder ball 1 is surely seated on the electrode 22. In this centering operation, the solder ball 1 and the array mask 3 remain in close contact with each other, or are separated so as not to disengage the solder ball 1 and the array mask 3 (the mounting stage 61 is slightly lowered. ).

  After completion of mounting, the suction state in the ball cup 4 is turned ON by the vacuum switching means, and suction is performed again. The solder balls 1 mounted on the substrate 2 do not rise due to contact with the flux and generate an adhesive force, and all the solder balls 1 not in contact with the flux are sucked up, floated, and adsorbed on the ball adsorber 42. become. Accordingly, the solder ball 1 can be supplied and recovered by one ball mounting means. In this state, the ball cup 4 moves above the convex portion of the array mask 3 which is the next mounting position. The movement to the next mounting position may be started simultaneously with turning on the suction state of the ball cup 4.

  After the mounting operation at the final mounting position is completed, the mounting stage 61 is lowered by the Z drive, and the substrate 2 is transferred from the mounting stage 61 to the unloading stage 71 by the X drive of the unloading pick & placer 72. Thereafter, the substrate 2 is unloaded by the unloading stage 71.

DESCRIPTION OF SYMBOLS 1 ...... Solder ball 2 ...... Board | substrate 3 ...... Arrangement mask 4 ...... Ball cup 5 ... ························································································································ ··· embedded substrate 21 ···································· 23 Flat mask 31 ... Through hole 32 ... Projection 33 ... Digging 41 ... Opening 42 ...・ Ball adsorbing body 43 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Upper space 44 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Lower space 45 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Suction passage 46 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Case 47 ・ ・ ・ ・ ・ ・·baud Cup X drive mechanism 48 ... Ball cup Y drive mechanism 49 ... Ball cup Z drive mechanism 51 ... Loading stage 52 ... Loading pick & Placer 61 ····················································································································・ ・ ・ ・ Projection amount a ・ ・ ・ ・ ・ ・ ・ ・ Gap

Claims (3)

An electrode is provided at the bottom, and a through hole is provided in accordance with an electrode arranged in a predetermined pattern on a substrate having a recess larger than the diameter of the conductive ball on which the depth to the top of the electrode is mounted. An array mask;
Ball mounting means for supplying conductive balls onto the array mask;
In a conductive ball mounting device for mounting a conductive ball on an electrode on a substrate through a through hole of the array mask,
The conductive ball mounting apparatus, wherein the array mask has a convex portion protruding on a surface facing the substrate corresponding to the concave portion of the substrate.
The protruding amount of the convex portion of the array mask is provided to be larger than the depressed amount of the concave portion of the substrate,
A moving means for relatively approaching and separating the array mask and the substrate;
2. The conductive ball mounting apparatus according to claim 1, wherein the ball mounting by the ball mounting means is performed in a state where the bottom surface of the convex portion and the bottom surface of the concave portion are in close contact with each other.
The ball mounting means includes ball holding means for adsorbing conductive balls by a ball adsorber provided on a lower surface of a casing connected to a vacuum source, and moving means for moving the ball holding means on the array mask. ,
Moving the ball holding means to a predetermined position above the array mask by the moving means;
3. The conductive ball mounting device according to claim 1, wherein the conductive balls adsorbed by the ball holding means are supplied onto the array mask after the connection between the casing and the vacuum source is released. .

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