JPH0211017B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bonding wire for a semiconductor device used to connect a chip electrode of a semiconductor device to an external lead.

This type of bonding wire is wound around a spool as shown in FIG.

In the figure, A is a spool around which a bonding wire 1 of a semiconductor element is wound.
is wound around the body 2a of the spool 2 so that a single-layer winding part a and a multi-layer winding part b continuous to the single-layer winding part a are formed. The first winding part a is the winding start end 1 of the wire 1.
It has a one-layer structure in which the wires a are fixed to the spool 2 and wound in line around the body 2a of the spool 2 over the length required for connection from the winding start end 1a to the wire breakage detection device. The multi-layer winding part b has a multi-layer structure by winding the wire 1 continuous from the single-layer winding part a back and forth in the multi-layer winding part b section. The above multilayer structure has aligned winding on both the reciprocating and returning sides.
Alternatively, it has a multi-layered cross-wound structure similar to a spool of thread.

Recently, with the development of high-speed automobile bonders, the bonding speed has increased and the amount of wire used has increased, so long windings such as 500 to 5000 m windings have been desired instead of the conventional 50 to 200 m windings.

However, when the multilayer winding part b was wound into a long length while maintaining the conventional multilayer structure, the following problems occurred.

That is, if the multilayer winding part b has a multilayer structure with aligned winding, the wire 1 will easily unravel and fall off during bonding work, and if the multilayer winding part b has a multilayer structure with cross winding, the wire 1 will become loose. There were problems such as the biting was too strong and it was difficult to unravel, causing wire breakage and reducing work efficiency.

The present invention has been made in view of the above-mentioned circumstances, and prevents the winding wire from unraveling and excessive biting by obtaining an appropriate engagement state of the winding wire in the multilayer winding part. Furthermore, it is an object of the present invention to provide a bonding wire for semiconductor devices that prevents wire breakage during bonding and improves workability.

Hereinafter, the present invention will be specifically described based on illustrated embodiments.

The bonding wire for the semiconductor device of the present invention is
Similar to the conventional bonding wire winding spool A shown in FIG. The winding part b is characterized by having a multilayer structure in which aligned winding layers and 1 to 20 cross winding layers are alternately laminated.

The multilayer structure of the multilayer winding part b will be explained as follows.

First, as shown in FIG.
The first layer is formed by winding them in the direction of the arrow (forward direction).

Next, the first layer of termination wire 1x shown in FIG.
A second layer is constructed by cross-winding the wire 1y continuous to the first layer in the direction of the arrow (in the backward direction) so as to overlap the first layer (FIG. 3).

Furthermore, the second layer terminal wire 1 shown in FIG.
A third layer is constructed in the same manner as the first layer so that the wire 1z continuous to y overlaps the second layer (FIG. 4).

Furthermore, to form a fourth layer, the second layer is cross-wound so as to overlap the third layer.

In this way, the multilayer winding part b of the present invention has a multilayer structure in which the first aligned winding layer and the second cross winding layer are alternately laminated.

In this case, the cross-wound layer has at least one turn,
It is necessary to use 20 or less cross-wounds.

At least one cross winding is sufficient to ensure proper engagement between the wound wires and loosening of the wound wires, but if there are more than 20 turns of cross winding, excessive biting of the wound wires may occur. This is because

Since the present invention is configured as described above, the wound wires are wound in a moderately engaged state, and it is possible to prevent wire breakage during bonding work due to excessive biting of the wires together. Moreover, it is possible to prevent the wound wire from falling off due to unraveling, and at the same time, it is possible to obtain a bonding wire for a semiconductor element that improves workability.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of a conventional bonding wire winding spool for a semiconductor device, and FIG. 2 is a main part showing the winding structure of the first layer of the multilayer winding portion of the bonding wire winding spool for a semiconductor device according to the present invention. A side view, FIG. 3 is a side view of a main part showing the winding structure of the second layer as above, and FIG. 4 is a side view of the main part showing the winding structure of the third layer as above. A... Bonding wire winding spool, 1... Bonding wire, 2... Spool, 1x... First layer bonding wire, 1y... Second layer bonding wire, 1z... Third layer bonding wire, a... First layer winding part, b ...Multi-layer winding section.

Claims (1)

[Claims] 1. In a bonding wire wound on a spool into a single-layer winding part and a multi-layer winding part continuous to the single-layer winding part, the above-mentioned multi-layer winding part is alternately laminated with aligned winding layers and 1 to 20 cross-winding layers. A bonding wire for semiconductor devices characterized by having a multilayer structure.