JP3255029B2 - Apparatus and method for mounting conductive ball - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive ball mounting apparatus and method for mounting conductive balls for forming bumps on electrodes of a work such as a chip or a substrate.

[0002]

2. Description of the Related Art In a process of manufacturing a work having a bump such as a flip chip, as a method of forming a bump (protruding electrode) on an electrode of the work, a method using a conductive ball such as a solder ball is known. As a method using conductive balls, the mounting head is moved above the conductive ball supply section, and the mounting head is moved up and down, so that a large number of conductive balls are attracted to the lower surface of the mounting head. After picking up, the mounting head is moved above the application part of the mucus such as flux or silver paste, where the mounting head is moved up and down so that the mucus adheres to the lower surface of the conductive ball. 2. Description of the Related Art There is known a method in which a plurality of conductive balls are collectively mounted on electrodes of a work by moving the work upward and vertically there.

[0003]

By the way, it is necessary to apply an appropriate amount of mucus to all the conductive balls held on the lower surface of the mounting head. For this reason, as a mucus application part,
It is known to use squeegee means. The squeegee means is for storing the mucus in a reservoir having a flat upper surface, and sliding the squeegee with a gap on the upper surface to smooth the liquid surface of the mucus on the upper surface. According to such a squeegee means, an appropriate amount of mucus can be adhered to all the conductive balls by causing a large number of conductive balls held on the lower surface of the mounting head to reach the mucus at a certain depth. it can.

[0004] The squeegee means spreads the mucus thinly on the upper surface of the storage section with a certain thickness. The mucus such as flux or silver paste contains a volatile component such as a solvent. For this reason, the volatile component tends to volatilize from the large surface area of the mucus spread widely on the upper surface of the storage part, and as a result, there is a problem that the viscosity of the mucus tends to increase with time. When the mucus thickens in this way, the adhesive force for bonding the conductive ball to the electrode of the work also fluctuates, and the quality of the bump formed by the conductive ball also varies.

Accordingly, it is an object of the present invention to provide a conductive ball mounting apparatus and a mounting method capable of preventing thickening of mucus over time.

[0006]

According to a first aspect of the present invention, a mucus application section includes a mucus storage section having a flat upper surface,
A first squeegee that scrapes and collects mucus on the upper surface by sliding on the upper surface, and a mucus collected by the first squeegee by sliding on the upper surface with a gap. A second squeegee that extends on the upper surface with a predetermined thickness.

According to a second aspect of the present invention, after the mounting head moves up and down to cause the mucus in the reservoir to adhere to the conductive balls,
By sliding the first squeegee on the upper surface of the reservoir to scrape and collect the mucus on the upper surface, and before the mounting head moves up and down again to attach the mucus to the conductive balls, By sliding the second squeegee on the upper surface with a gap, the mucus collected by the first squeegee is spread on the upper surface with a predetermined thickness.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first and second aspects of the present invention, if the mounting head moves up and down to cause the mucus on the upper surface of the storage portion to adhere to the conductive balls, the first squeegee can be used to move the upper surface of the storage portion. Since the upper mucus is collected, the time during which the mucus becomes a thin film having a large surface area and is widely spread on the upper surface can be greatly reduced, and therefore, the volatilization of volatile components contained in the mucus is suppressed, and the time of the mucus elapses. It is possible to prevent thickening.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a conductive ball mounting apparatus according to an embodiment of the present invention, FIGS. 2 (a), 2 (b) and 2 (c) are side views of an application portion of the mucus, and FIG. It is a top view of an application part.

In FIG. 1, reference numeral 1 denotes a conductive ball,
The conductive balls are stored in a container 2 serving as a supply unit. Reference numeral 3 denotes a base on which the container 2 is placed. Inside the base 3, in order to fluidize the conductive balls 1 in the container 2,
Vibration means for vibrating the container 2 and gas supply means for feeding gas into the container 2 are incorporated. The container 2 and the base 3 constitute a supply section of the conductive ball 1.

In FIG. 1, reference numeral 10 denotes a work, which is positioned on a clamper 11 by a clamp. The clamper 11 is supported by a column 13 erected on a base 12. The clamper 11, the base 12, and the support 13
This is the positioning part. A mucus application unit 14 is provided between the container 2 and the base unit 12. Next, the mucus application section 14 will be described with reference to FIGS.

In FIG. 2A, reference numeral 15 denotes a shallow container-shaped storage section, on which a thin mucus 4 is stored on a flat upper surface a. The mucus 4 is a flux, a silver paste, or the like, and contains a volatile component such as a solvent.
A moving table 16 is provided above the container 15. Two cylinders 19 and 20 are provided on the moving table 16 in an inverted manner.
Squeegee 17 and the second squeegee 18 are connected. The moving table 16 is driven by driving means (not shown) and moves in the horizontal direction N. The rod 1 of the cylinder 19, 20
When 9a and 20a go down and down, the first squeegee 17 and the second
Squeegee 18 moves up and down. As shown in FIG.
The width of the squeegee 18 is considerably smaller than the width of the first squeegee 17.

In FIG. 1, reference numeral 22 denotes a mounting head.
The mounting head 22 is held below the box 23. A motor 24 is provided above the box 23. The box 23 has built-in vertical movement means such as a feed screw driven by a motor 24.
When 4 is driven, the mounting head 22 moves up and down. The mounting head 22 is connected to a pneumatic unit (not shown). When the pneumatic unit is driven, the conductive ball 1 is vacuum-adsorbed and held on the lower surface of the mounting head 22, and the vacuum suction state is released. The conductive ball 1 is dropped.

The box 23 is held on a horizontally long moving table 26 as moving means. The moving table 26 has a built-in feed screw mechanism. When the motor 27 is driven to operate the feed screw mechanism, the mounting head 22 moves between the container 2 and the work 10 in the horizontal direction as indicated by an arrow.

The conductive ball mounting apparatus is constructed as described above, and the operation will be described below. In FIG. 1, the mounting head 22 moves above the container 2 and performs a lowering / upward operation, whereby the conductive ball 1 is vacuum-adsorbed and picked up on its lower surface.

Next, the mounting head 22 moves above the storage section 14. Prior to this, as shown in FIG.
The squeegee 17 lands on the upper surface a of the storage unit 15, and the second squeegee 18 slides rightward in a state of being retracted upward to scrape off the mucus 4 on the upper surface a, and as shown in FIG. 4 is collected on the side of the storage unit 15. Then, when the mounting head 22 has moved above the storage section 15, the first squeegee 17 is retreated upward and the second squeegee 18 is lowered. Then, as shown in FIG. 2C, the second squeegee 18 is slid to the left. By sliding with a small gap G between the lower end of the second squeegee 18 and the upper surface a of the storage portion 15, the mucus 4 is spread on the upper surface a with a thin film thickness determined by the gap G. .

Next, by causing the mounting head 22 to move up and down, the mucus 4 adheres to the lower surface of the conductive ball 1 vacuum-adsorbed to the lower surface of the mounting head 22. Next, the mounting head 22 moves above the work 10 in FIG.
Then, the mounting head 22 descends to land the conductive ball 1 on the electrode of the work 10. Next, when the vacuum suction state of the conductive ball 1 is released and the mounting head 22 is raised,
The conductive ball 1 is mounted on an electrode of the work 10. The work 10 on which the conductive balls 1 are mounted is sent to a heating furnace (not shown), and the conductive balls 1 are melted and solidified by heating to form bumps.

As shown in FIG. 2 (b), the mucus application unit 14 stores the mucus 4 except when the mounting head 22 is moved up and down to apply the mucus 4 to the conductive balls 1 as described above. The mucus 4 on the upper surface a of the portion 15 is
As shown in FIG. 2 (c), only when the mucus 4 adheres to the conductive ball 1, the mucus 4 is collected as a lump having a small surface area on the side of the reservoir 15. It expands to the top. Therefore, FIG.
In the state shown in (b), the amount of volatile components contained in the mucus 4 is extremely small, and the mucus 4 can maintain a desired viscosity for a long time. Further, as shown in FIG. 3, by making the width of the first squeegee 17 larger than the width of the second squeegee 18, the mucus 4 is unnecessarily expanded in the width direction to prevent volatile components from being volatilized. Can be prevented.

FIG. 4 is a plan sectional view of a first squeegee and a second squeegee of a conductive ball mounting apparatus according to another embodiment of the present invention. On both sides of the first squeegee 17A,
A bent portion 171A bent toward the second squeegee 18 is formed. Therefore, the bent portion 171A can prevent the mucus 4 from being unnecessarily spread in the lateral width direction. Of course, the width of the first squeegee 17A is larger than the width of the second squeegee 18.

[0020]

According to the present invention, the mucus on the upper surface of the reservoir is collected by the first squeegee if the mucus on the upper surface of the reservoir is adhered to the conductive balls by the vertical movement of the mounting head. The time during which the mucus becomes a thin film having a large surface area and is widely spread on the upper surface can be greatly reduced, so that the volatilization of volatile components contained in the mucus can be suppressed, and the viscosity of the mucus over time can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view of a conductive ball mounting apparatus according to an embodiment of the present invention.

FIG. 2A is a side view of a portion for applying a mucus of a conductive ball mounting apparatus according to an embodiment of the present invention; FIG. 2B is a side view of a mucous application of a conductive ball mounting apparatus according to an embodiment of the present invention; (C) Side view of mucus application unit of conductive ball mounting device according to one embodiment of the present invention

FIG. 3 is a plan view of a mucus application section of the conductive ball mounting apparatus according to one embodiment of the present invention;

FIG. 4 is a plan sectional view of a first squeegee and a second squeegee of a conductive ball mounting apparatus according to another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 conductive ball 2 container 4 mucus 10 work 14 mucus application unit 15 mucus storage unit 17, 17A first squeegee 18 second squeegee 22 mounting head 26 moving table

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/60

Claims (2)

(57) [Claims] 1. A conductive ball supply section, a section for applying a mucus containing a volatile component, a work positioning section, and a mounting head. The conductive ball supply section is provided on a lower surface of the mounting head. After holding and picking up the conductive ball, the mounting head is moved above the application portion of the mucus, and the mounting head is moved up and down so that the mucus adheres to the lower surface of the conductive ball. A conductive ball mounting device that moves the work head up and down so that the mounting head moves up and down to mount the conductive ball on the electrode of the work. A mucus reservoir having a flat upper surface, a first squeegee for scraping and collecting mucus on the upper surface by sliding on the upper surface, and sliding with a gap on the upper surface. And a second squeegee that spreads the mucus collected by the first squeegee on the upper surface with a predetermined thickness. 2. The method according to claim 1, wherein the mounting head is positioned above the conductive ball supply unit, and the mounting head is moved up and down to hold and pick up the conductive balls on the lower surface of the mounting head. Is driven to move the mounting head to the application part of the mucus containing volatile components, where the mounting head is moved up and down, thereby conducting the mucus on the flat upper surface of the storage part provided in this application part. By attaching the conductive ball to the lower surface of the work ball, the moving means is then driven to move the mounting head above the work, and the mounting head is moved up and down so that the conductive ball is mounted on the electrode of the work. A method of mounting a conductive ball according to claim 1, wherein the mounting head moves up and down to attach the mucus of the reservoir to the conductive ball, and then a first squeegee is placed on the upper surface. By sliding, the mucus on the upper surface is scraped and collected, and then, before the mounting head moves up and down again to adhere the mucus to the conductive balls, a gap is formed on the upper surface by a gap. The method of mounting a conductive ball, wherein the liquid collected by the first squeegee is spread on the upper surface by a predetermined thickness by sliding.