JPH0391990A - Bonding device for semiconductor device - Google Patents

Abstract

PURPOSE:To mount semiconductor devices on both the sides of a printed wiring board with a small pressure making them confront each other in a short time by a method wherein a conductive pattern on which solder is applied and outer leads are heated and connected together by a single bonding tool at the same time. CONSTITUTION:A semiconductor device 10 is placed on a printed wiring board 11, and outer leads 3 of the semiconductor device 10 are aligned with a conductive pattern 12. Keeping them in this state, when a bonding tool 13a heated by a heater 17 is made to descend, a first bearing part 14a approaches to or comes into contact with a conductive pattern on which solder is applied and a second bearing part 15 is made to come into contact with a carrier film 1. When the bonding tool 13a is pressured, solder applied onto the conductive pattern 1 is fused. By this setup, outer leads 3 are connected to the conductive pattern 12 in a short time, and when semiconductor devices 10 and 10a are mounted on both the sides of the printed wiring board 11 at symmetrical positions, the mounting concerned can be carried out by combining a bonding device with a printed wiring board reversing device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bonding device for mounting a semiconductor device on a board, and more specifically, for bonding an outer lead of the semiconductor device to a conductive pattern or the like of a printed wiring board. This invention relates to a bonding device.

[Prior Art] Generally, in a semiconductor device, a semiconductor element is attached to a die pad provided on a lead frame, the external electrodes of the semiconductor element and the terminals of the lead frame are connected with wires, and these are made of thermosetting resin such as epoxy resin. After packaging, each terminal is cut and manufactured.

Nowadays, as electronic devices become smaller and thinner, the semiconductor devices used therein are also packaged in higher density, so there is a desire for thinner and smaller semiconductor devices. In order to meet these demands, semiconductor elements are placed in device holes of carrier films such as polyimide films,
The electrodes of this semiconductor element are directly connected to the terminals provided on the inner leads of the carrier film, and liquid resin (
For example, semiconductor devices packaged by printing or potting a sealant made of epoxy resin have come into use.

FIG. 4 is a plan view for explaining a conventional semiconductor device using a carrier film, and FIG. 5 is an enlarged sectional view taken along line A--A. In the figure, 1 indicates a thickness 75 in which device holes 2, 2a, 2b, . . . having an area larger than the surface area of semiconductor elements 6, 6a, 6b, . It is a carrier film of about ~100 IIm. Numeral conductive patterns (hereinafter referred to as outer leads) 3 are provided on the carrier film 1 and are made of metal foil such as copper with high conductivity and have a thickness of about 30 to 40 mm and a width of about 50 to 300 mm. A portion thereof protrudes into the device hole 2 to form an inner lead 3a, and a terminal 4 connected to the electrodes of the semiconductor elements 6 to 6b is provided at the tip thereof. 5 is a sprocket hole for conveying the carrier film 1.

Inner lead 3a of carrier film 1 as described above
To bond the semiconductor element 6 to the electrodes of the semiconductor element 6, the semiconductor element 6 is placed on a bonding stage (not shown), and the numerous electrodes provided on the semiconductor element 6 and the terminal 4 of each inner lead 3a are bonded. Match each. Next, a bonding tool (not shown) with a built-in heater is lowered, brought into contact with each inner lead 3a, and pressed down to form each inner lead 3a at a predetermined angle.
Each terminal 4 is fused to an electrode and connected. When bonding is completed, the active surface of the semiconductor element 6 is sealed with a resin or the like, and the base of the outer lead 3 is cut to complete the manufacture of the semiconductor device 10.

In order to mount the semiconductor device 10 as described above on a printed wiring board, as shown in FIG.
is placed on a heating table 7 having a built-in heater 8, and the conductive pattern t2 is heated from below. And printed wiring board 1
A semiconductor device 10 is placed on top of the semiconductor device 10, and each outer lead 3 is aligned with a conductive pattern l2 coated with solder. Next, the bonding tool 13 heated by the built-in heater 17 is lowered and its tip 14 is brought into contact with the outer lead 3 via the carrier film 1,
The conductive pattern 12 is melted by heating and pressurizing the solder.
Connect outer lead 3 to.

[Problem to be solved by the invention] In the conventional mounting method as described above, the printed wiring board 1
Since it is necessary to preheat (approximately 150° C.) from the bottom of the printed wiring board 1l, not only does the device become large and expensive, but also the semiconductor device IO must be mounted facing both sides of the printed wiring board 1l in order to increase the packaging density. I couldn't.

In addition, since the bonding tool 13 heats the outer lead 3 and the conductive pattern l2 via the carrier film 1 with low thermal conductivity, the bonding tool 13 has a high temperature (the temperature of the tip part is 350 ~
400℃) and heavy pressure (10-30kg/cd
), there were problems such as having to press-bond for a long time (15 to 20 seconds including cooling). In order to shorten the pressure bonding time, it may be possible to heat the bonding tool 13 to a higher temperature, but if this is done, there is a risk that the carrier film 1 will melt, so the temperature is limited to 350 to 400°C.

The present invention was made in order to solve the above problems, and it is possible to mount semiconductor devices facing both sides of a printed wiring board without requiring preheating from below, and in addition, with light pressure and a short time. The purpose of this invention is to obtain a bonding device for semiconductor devices that can be mounted in a short period of time.

[Means for Solving the Problems] A bonding device for a semiconductor device according to the present invention includes a first contact portion that contacts a conductive pattern on the outer periphery of a tip of a bonding tool, and a first contact portion that contacts a conductive pattern. A second abutting part that abuts the outer lead or the carrier film is provided inside the part.

Further, a first contact portion is provided at the center of the tip of the bonding tool, and second contact portions are provided on both sides of the first contact portion.

[Operation] When the bonding tool with a built-in heater is lowered,
The first contact portion contacts the conductive pattern coated with solder, and the second contact portion contacts the carrier film or the outer lead and heats them.

When the bonding tool is applied with pressure after soldering, the solder melts and the outer lead is connected to the conductive pattern.

[Embodiment] FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 is a bottom view of the bonding tool. Note that the same parts as in the conventional example explained in FIG. 6 are denoted by the same reference numerals, and the explanation will be omitted. In the figure, reference numeral 13a denotes a bonding tool, and a first contact part 14a is provided on the outer periphery of the lower surface of the tool to come into contact with the conductive pattern l2 of the printed wiring board 1l during bonding. A second abutting portion l5 is formed which is deeper by d than the first abutting portion 14a that abuts on.

Here, the depth d of the second contact portion 15 is set to d≦tt+t2, where t is the thickness of the carrier film 1 and t2 is the thickness 1 of the outer lead 3.

For example, t = 100 us St 2 - 40
-, d1 should be 140 μm or slightly shallower. lB is the second
This is a recess formed in the center of the bonding tool 13a following the contact NL5 to avoid interference with the semiconductor device 10.

Next, the operation of the present invention will be explained. First, the semiconductor device 10
are placed on the printed wiring board 1l, and the outer leads 3 are aligned with the conductive patterns 12, respectively. In this state, heat with heater l7 (temperature at the tip is 350 to 40
When the bonding tool 13a that has been heated to 0° C. is lowered, the first contact portion 14. a is close to or in contact with the conductive pattern 12 coated with solder, and the second contact portion l5 is in contact with the carrier film 1.

Then, pressurize the bonding tool 13a (3 kg
/ cd or less), the solder applied to the conductive pattern l2 melts, and the outer lead 3 is heated for a short time (1 to 2,5
seconds) to connect to the conductive pattern 12.

In addition, when mounting semiconductor devices 10.10a at symmetrical positions on both sides of the printed wiring board 11, a reversing device for the printed wiring board 1l is combined with the bonding device, and the semiconductor device 10.10a is mounted on one side of the printed wiring board 11 (for example, )
If the printed wiring board 11 is reversed after mounting the
Another semiconductor device 10 can be mounted on the other surface. Further, by temporarily bonding the semiconductor device IO to one surface (lower surface) of the printed wiring board L1, the semiconductor device 10 is simultaneously bonded to both sides using two bonding tools. l
OG can be mounted, or a semiconductor device can be mounted on the back side of a semiconductor device that has already been mounted, allowing high-density mounting.

FIG. 3 is a sectional view showing another embodiment of the present invention. In this embodiment, a first contact part 14b is provided at the center of the bottom surface of the bonding tool tab, and second contact parts 14b are provided on both sides of the first contact part 14b.
contact portion 15a. 15b is provided.

In this embodiment configured as described above, FIG.
), first, the conductive pattern l2 on one side (the right side in the figure) and the outer lead 3 are connected using the bonding tool 13b, and then the bonding tool 13
b is moved in the direction of the arrow to connect the conductive pattern 12 on the other side (the left side in the figure) and the outer lead 13 as shown in FIG. 3(b). When mounting a large number of semiconductor devices,
Particularly effective.

In the above embodiment, the present invention was explained as an example of mounting a semiconductor device using a carrier film, but the present invention can also be implemented when mounting other semiconductor devices on a board, such as a semiconductor device using a lead frame. I can do it.

[Effects of the Invention] As detailed above, the present invention uses one bonding tool to heat and connect the conductive pattern coated with solder and the outer lead at the same time. effect can be obtained.

(1) A heating table for preheating the printed wiring board is not required, and the equipment can be simplified.

Further, since semiconductor devices can be mounted facing both sides of the printed wiring board, high-density packaging is possible.

(2) The pressurizing force of the bonding tool can be reduced to 1/3 or less compared to the conventional method, and the bonding time can also be reduced to 1/6 or less compared to the conventional method, so productivity can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a bottom view of the bonding tool, and FIG. 3(a). (b) is an explanatory diagram of another embodiment of the present invention, FIG. 4 is an explanatory diagram of a semiconductor device using a carrier film, FIG. FIG. 1: carrier film, 3: outer lead, 3a: inner lead, 6: semiconductor element, 10: semiconductor device, 1
1: Printed wiring board, l2: Conductive pattern, 13a.
l3b: bonding tool, 14a. l4b: 1st
contact portion, 15. l5a. L5b: second contact part, L
7: Heater.

Claims (2)

[Claims] (1) In an apparatus for connecting an outer lead of a semiconductor device to a conductive pattern provided on a substrate using a bonding tool, a first contact portion that contacts the conductive pattern is provided at the tip of the bonding tool; A bonding device for a semiconductor device, characterized in that a second contact portion that contacts the outer lead or the carrier film is provided inside the contact portion of the semiconductor device. (2) Claim (1) characterized in that a first contact portion is provided in the center of the tip of the bonding tool, and second contact portions are provided on both sides of the first contact portion. ) A bonding apparatus for a semiconductor device according to the above.