JPH0547845A - Lead bonder - Google Patents

Abstract

PURPOSE:To provide means capable of bonding a lead of a device by pressing uniformly the lead on a substrate even when a top face of the substrate is inclined for an outer lead bonding. CONSTITUTION:A lead bonder comprises a leaf spring 1 flexible in all directions consisting of a plurality of slits 11, a holder 12 for holding the leaf spring 1 horizontally, a positioning part 2 of an electric component 20 provided on a center part of the leaf spring 1, and means 16 for supporting the positioning part 2 flexibly from the lower direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead bonding apparatus, and more particularly to an apparatus for positioning an electric component such as a substrate or a semiconductor chip and bonding the lead to the electric component.

[0002]

2. Description of the Related Art A device manufacturing process known as the TAB method is obtained by an inner lead bonding process of bonding a chip to a lead of a film carrier formed of a synthetic resin film such as polyimide, and then punching the film carrier. And an outer lead bonding process for bonding the device leads to the substrate.

[0003]

An inner lead bonding apparatus for automatically performing inner lead bonding is now in widespread practical use.
However, outer lead bonding requires extremely high accuracy, and if the upper surface of the board is slightly inclined due to molding errors, etc., all leads should be evenly bonded to the electrodes of the board without uneven pressure. Since it is extremely difficult, a technique for automatically performing this has not been sufficiently established. Therefore, at present, outer lead bonding is performed by a worker only by hand.

Therefore, the present invention relates to lead bonding,
In particular, it is an object of the present invention to provide a device that corrects the inclination of the upper surface of the substrate when the upper surface of the substrate is inclined and presses the leads against the substrate with a uniform force to perform bonding without uneven pressure.

[0005]

To this end, according to the present invention, a leaf spring, which is formed by forming a plurality of slits and is bendable in all directions, and an outer edge portion of the leaf spring are mounted, the leaf spring is made horizontal. A holder for holding in a posture, a positioning portion for the electric component provided in the central portion of the leaf spring, and a supporting means for swingably supporting the positioning portion from below constitute a lead bonding device.

[0006]

In the above structure, when performing outer lead bonding, for example, the head mounts the device on the substrate positioned in the positioning portion, and the device lead is bonded to the electrode on the substrate. If the upper surface of the board is inclined, the leaf spring bends due to the load applied when the thermocompressor is pressed against the lead in order to thermocompress the lead to the electrode of the board, and the board is placed on the lower surface of the thermocompressor. Correct the tilted posture so that it follows. Further, the strong load applied from the thermocompressor is supported by the supporting means, and the leads are bonded to the substrate with a uniform force without uneven pressure.

[0007]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a side view of the bonding apparatus, and FIG. 2 is a plan view. This device has a substrate 20 as an electric component.
An apparatus for outer lead bonding the lead L of the device P. The device P is made by punching a film carrier by the TAB method.

Reference numeral 1 is a leaf spring in the shape of an ultrathin disc, and a positioning portion 2 for a substrate 20 is attached to the center of the leaf spring. The positioning portion 2 has a disk shape, and the substrate 2
The receiving portion 3 of 0 is provided in a frame-like shape, and a suction hole 4 is bored therein. The suction holes 4 vacuum-suck the substrate 20 on the receiving portion 3 so as not to rattle during bonding. 5 is a set screw.

As shown in FIG. 2, a large number of arc-shaped slits 11 are alternately formed in the leaf spring 1 so that the leaf spring 1 is bendable in all directions. The positioning portion 2 attached to the central portion can freely swing and tilt while bending the leaf spring 1 (see the chain line in FIG. 1).

The leaf spring 1 has its outer edge portion attached to the holder 12 by a set screw 13 and is held in a horizontal posture on the holder 12. Reference numeral 14 is a lower receiving member provided below the positioning portion 2, and is coupled by the set screw 5 so as to hold the inner peripheral edge of the leaf spring 1 by both 2 and 14. A heater 15 is provided on the lower surface of the positioning unit 2. The heater 15 heats the substrate 20 via the positioning portion 2 so that the leads L can be bonded to the substrate 20 well.

A universal joint consisting of a bearer ring 16 as a support means is interposed between the lower receiving member 14 and the holder 12. Therefore, the lower receiving member 14 and the positioning portion 2 integrated therewith are supported on the bearing ring 16 from below and can freely swing, and a large load applied to the positioning portion 2 is applied to the holder 12 via the bearing ring 16. Supported.

The holder 12 is a rod 1 of the cylinder 17.
The height of the positioning part 2 can be adjusted by the rod 18 protruding and retracting. Also cylinder 1
7 is an X table 21, a Y table 22, and a θ table 2
The positioning section 2 is moved in the XY directions and horizontally rotated by driving these tables 21 to 23.

Reference numeral 24 is a first head, and its nozzle 2
The substrate 20 is sucked onto the substrate 5 and mounted on the positioning portion 2. Further, reference numeral 26 is a second head, which adsorbs the device P on its nozzle 27 and mounts it on this substrate 20. 28
Is a thermocompression bonding element for pressing and bonding the lead L to the electrode of the substrate 20. 29 is a camera, head 26
The positional deviation of the lead L of the device P sucked by the nozzle 27 is measured. A laser device or the like can also be applied as such measuring means. The present apparatus has the above-mentioned configuration, and the operation will be described below.

First, the head 24 mounts the substrate 20 on the positioning portion 2. In addition, the head 26 that adsorbs the device P
Arrives above the camera 29, and the positional deviation of the lead L in the XYθ directions is measured. Next, based on this measurement result, the tables 21 to 23 are driven to move the substrate 20 to XYθ.
Direction to correct this misalignment.

Next, the head 26 reaches above the positioning portion 2, and then the nozzle 27 descends to land the lead L of the device P on the electrode of the substrate 20. Next, the thermocompression bonding element 28 descends to press the lead L against the electrode of the substrate 20 and perform thermocompression bonding.

By the way, the upper surface of the substrate 20 positioned by the positioning portion 2 is not limited to a perfect horizontal surface, but may be inclined due to a molding error or the like. If the substrate 20 is slightly inclined, the thermocompression-bonding elements 28 cannot press all the leads L against the substrate 20 with uniform strength, resulting in uneven pressing and failing to perform good bonding.

FIGS. 3A and 3B show the substrate 20 as described above.
2 shows a state of bonding when the upper surface of the is tilted. α is the tilt angle. In this case, when the nozzle 27 descends and the device P lands on the substrate 20, the pressing force of the device causes the leaf spring 1 to bend, and the posture of the substrate 20 is corrected so that the upper surface of the substrate 20 becomes horizontal. It Next, the thermocompressor 28 descends and presses the lead L strongly against the electrode of the substrate 20 (see FIG. 3B), but the strong load is supported by the holder 12 via the bearing 16.

As described above, according to this means, the posture of the substrate 20 is corrected so that the upper surface of the substrate 20 becomes horizontal, so that the thermocompression-bonding elements 28 are pressed against all the leads L by an even force. The lead L can be bonded to the substrate 20 without uneven pressure. In particular, since the leaf spring 1 can be bent even with a slight load, the slight inclination of the upper surface of the substrate 20 can be sufficiently dealt with only by the bending deformation of the leaf spring 1, and the lead L is firmly thermocompressed to the substrate 20. Since a large load applied to the substrate 20 from the thermocompression bonding element 28 is supported by the holder 12 side via the bearing 16, the thermocompression bonding element 28 is used.
Stable bonding can be performed while pressing the lead L strongly against the lead L. Of course, the supporting means of the lower receiving member 14 is not limited to the bearing 16, and any means can be used as long as it can firmly support the positioning portion 2 swingably.

This device is applicable not only to outer lead bonding but also to inner lead bonding.
FIG. 4 is a side view during inner lead bonding.
Reference numeral 30 denotes a semiconductor as an electric component, which is mounted on the positioning portion 2. 31 is a film carrier,
The lead is pressed against the electrode 33 on the upper surface of the semiconductor 30 by the pressing element 32 to perform bonding. In this case, the tilted posture of the semiconductor 30 is corrected by bending the leaf spring 1 as in the case described above.

[0021]

As described above, according to the present invention, a leaf spring which is formed by forming a plurality of slits and is bendable in all directions, and an outer edge portion of the leaf spring are attached to the leaf spring in a horizontal posture. Since the holder for holding, the positioning portion of the electric component provided in the central portion of the leaf spring, and the support means for swingably supporting the positioning portion from below constitute a lead bonding device, the outer In lead bonding, when the substrate is tilted, this can be corrected to a horizontal posture, and all leads can be bonded with a uniform force without uneven pressure.

[Brief description of drawings]

FIG. 1 is a sectional view of a bonding apparatus according to the present invention.

FIG. 2 is a plan view of a bonding apparatus according to the present invention.

FIG. 3 is a side view of a main part during outer lead bonding according to the present invention.

FIG. 4 is a side view of a main part during inner lead bonding according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Leaf spring 2 Positioning part 11 Slit 12 Holder 16 Supporting means 20 Electrical component 30 Electrical component

Claims (1)

[Claims] 1. A leaf spring which is formed by forming a plurality of slits and is bendable in all directions, a holder to which an outer edge portion of the leaf spring is attached and which holds the leaf spring in a horizontal posture, and a leaf spring of the leaf spring. A lead bonding apparatus comprising: a positioning part for an electric component provided in a central part; and a supporting means for swingably supporting the positioning part from below.