JPH04146638A - Bonding head for thermocompression bonding - Google Patents

Abstract

PURPOSE:To enable a led to be thermocompression bonded to a tilted substrate under even pressure by a method wherein the slits in XY direction are formed on a frame type leaf spring and a thermocompression bonding element is fitted to the opening of the leaf spring while a lifting means is fitted to the outer edge part of the leaf spring. CONSTITUTION:A leaf spring 10 partially formed of the slits 14a-15b having XY directional components becomes omnidirectionally bendable while the thermocompression bonding element 6 held by the opening 11 of the leaf spring 10 can be freely titled omnidirectionally. A bonding head sucking at a semiconductor chip P by a nozzle 2 is lowered down to the position above a substrate 3 so as to land a lead L on the substrate 3 and then a press element 20 is lowered so that the element 6 may press down the lead L on the substrate 3 to thermocompression bond the lead L to the substrate 3. Through these procedures, the thermocompression bonding element 6 is titled along the surface of the substrate 3 even if the substrate 3 is previously titled so that the lead L may be thermocompression bonded to the substrate 3 under even pressure owing the to the deformation of the leaf spring 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bonding head for thermocompression, and more particularly to a means for thermocompression bonding a lead extending outward from a semiconductor to a substrate without uneven pressure.

(Prior Art) It is known as the so-called TAB method that a semiconductor chip is formed by bonding a semiconductor to a film carrier tape made of a synthetic resin such as polyimide and then punching out the film carrier tape.

Bonding a semiconductor chip manufactured in this manner onto a substrate is generally called outer lead bonding. This outer lead bonding involves landing the lead extending outward from the semiconductor onto the electrode part of the substrate.
This is done by pressing a thermocompression bonder onto this lead and thermocompression bonding.

(Problems to be Solved by the Invention) The upper surface of the substrate on which outer lead bonding is performed as described above is not necessarily a perfectly horizontal surface, but may be an inclined surface due to bending or the like. When the board is tilted like this, pressing the thermocompression bonder onto the leads causes uneven pressure, making it difficult to uniformly thermocompress all the leads, which extend in multiple directions from the semiconductor, onto the board. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermocompression bonding head that can evenly press and bond leads to a substrate even when the substrate is tilted.

(Means for Solving the Problems) The present invention includes a nozzle for adsorbing a semiconductor chip formed by punching out a film carrier tape, and a nozzle on the side of the nozzle for attaching leads extending from the semiconductor to a substrate. A thermocompression bonder for thermocompression bonding, a heating means for heating the thermocompression bonder, and a frame-shaped plate spring for holding the thermocompression bonder, and a slit in the XY force direction is partially formed in the plate spring. The thermocompression bonder is attached to the opening of the leaf spring, and the outer edge of the leaf spring is attached to a lifting means to form a bonding head for thermocompression.

(Function) In the above configuration, the nozzle that has attracted the semiconductor chip descends to land the leads on the substrate.

Next, the leads are pressed against the substrate using a thermocompression bonder, and the leads are thermocompression bonded to the substrate. At that time, if the top surface of the board is tilted, the bending nature of the plate causes the thermocompression bonder to tilt so that its bottom surface follows the top surface of the board, press the leads against the board with even force, and apply heat. Crimp.

(Example) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a front view of a bonding head for thermocompression.

Reference numeral 1 denotes a nozzle shaft, and a nozzle 2 for sucking a semiconductor chip P is attached to the lower end of the nozzle shaft. This semiconductor chip P is formed by punching out a film carrier tape, and has a large number of leads L extending from the semiconductor C in multiple directions.

3 is a substrate on which the semiconductor chip P is mounted.

4 is a heat block as a heating means provided on the side of the nozzle shaft 1, and a heat transfer element 5 is attached to the lower part of the heat block. 6 is a thermocompression bonder provided on the side of the nozzle 2. The heat transfer element 5 comes into contact with and separates from the thermocompression bonder 6, and transfers the heat of the heat block 4 to the thermocompression bonder 6. Reference numeral 10 denotes a leaf spring for holding the thermocompression bonder 6, which will be explained next with reference to FIG. This leaf spring IO has a frame shape, and has a rectangular central opening 11. The thermocompression bonder 6 is attached to this opening 11 with screws 12. 13 is a screw hole. Outside slits 14a, 14b and inside slits 15a, 15b are formed to surround this opening 11. Slit 14a
, 14b, 15a, +5b are approximately frame-shaped having components in the X direction and the Y direction, and tie bar portions 16a, 16b, 17
It is formed with the exception of a and +7b. Tie bar part 16a
, 16bli are formed facing each other on the X axis. Further, the tie bar portions 17a and 17b are formed to face each other on the Y axis. In this way, by leaving the tie bars 16a to 17b and partially forming the slits 14a to 15b having the XY force direction components, the leaf spring 10 can be bent in all directions and is held in the leaf spring 10. The heated thermocompression bonder 6 can be freely tilted in all directions.

In FIG. 1, a rod 19 as a lifting means is attached to a bearing portion 18 so as to be able to rise and fall freely, and a rod 19 is a resilient coil spring. The outer edge of the plate spring 1° is attached to the lower end of the rod 7. 8 is the screw for installation, the second
In the figure, 9 is a screw hole. A presser 20 is provided above the rod 7. This presser 2° is driven by a drive means (not shown) to move up and down and press down the rod 7.

This honding head has the above structure, and its operation will be explained next.

The honding head, which has attracted the semiconductor chip P to the nozzle 2, arrives above the substrate 3. Next, the nozzle 2 descends and the lead L lands on the substrate 3. Next, presser 2
By lowering o, the thermocompression bonder 6 presses the lead L against the substrate 3 and thermocompression bonds the lead L. When the substrate 3 is tilted as shown in FIG. A large number of leads L extending in the direction are thermocompression bonded to the substrate 3 with uniform force.

When the thermocompression bonding is completed in this manner, the nozzle 2 and the thermocompression bonding element 6 are raised, and the next semiconductor chip P is bonded onto the substrate 3 by the same operation as described above.

(Effects of the Invention) As explained above, the present invention includes a nozzle that sucks a semiconductor chip formed by punching out a film carrier tape, and a lead provided on the side of this nozzle that extends from the semiconductor. It is equipped with a thermocompression bonder that is thermocompression bonded to a substrate, a heating means that heats the thermocompression bonder, and a frame-shaped leaf spring that holds the thermocompression bonder, and a slit in the X and Y directions is partially formed in the leaf spring. The above-mentioned thermocompression bonder is attached to the opening of this leaf spring, and the outer edge of this leaf spring is attached to the elevating means, so if the board is tilted, the thermocompression bonder will not touch the top surface of the board. The leads can be easily tilted in all directions along the board, and the leads can be thermocompressed by pressing them against the board with even force.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a front view of a pounding head, FIG. 2 is a plan view of a leaf spring, and FIG. 3 is a front view during pounding. 2... Nozzle 3... Substrate 4... Heating means 6... Thermocompression bonder 7... Lifting means 11... Openings 14a to 15b... Slits 16a to 17b... Tie bar 1 Department

Claims (1)

[Claims] A nozzle that sucks a semiconductor chip formed by punching out a film carrier tape, a thermocompression bonder located on the side of this nozzle that thermocompresses the leads extending from the semiconductor onto a substrate, and a thermocompression bonder that It is equipped with a heating means for heating and a frame-shaped leaf spring that holds the thermocompression bonder, a slit in the XY direction is partially formed in the leaf spring, and the thermocompression bonder is attached to the opening of the plate spring. In addition, a bonding head for thermocompression is characterized in that the outer edge of the leaf spring is attached to an elevating means.