Esec Sa

Marit Seidel

Hans Egger

Daniel Von Flue

In a method of making a wire connection of predetermined shape between a first connecting point located on a semiconductor chip and a second connecting point a capillary is moved along a predetermined trajectory. After attaching the wire at the first connecting point the capillary is moved up to a first point for the performing of one or two kinks and for the pulling out of the wire as far as the required total length of the wire connection. From the first point, the capillary is moved along a circular arc up to a second point, at which the wire is locked in the capillary. The circular arc is centered in the first connecting point or in the immediate vicinity of the first connecting point. The method is suitable for the wiring of CSPs (Chip Scale Packages). The movement along the circular arc prevents the wire from being pushed back through the capillary. As soon as the wire is locked in the capillary, the second connecting point can be approached without difficulty.

Method of making wire connections of predetermined shape

On the production of wire connections (wire bonding) which start from a semiconductor chip and end on a substrate (2b) the capillary (12) guiding the wire (3) should be moved to an end section (s3) of its trajectory in a specific, programmed way in order to eliminate as far as possible reactions on the geometry of the wire bridge on bonding of the wire to the substrate and to produce flawless bond connections. The end section (s3) in which the capillary (12) moves slowly begins at a predetermined height (H) and ends on the substrate at the second connection point (5). In the end section (s3) the downward movement (vv) of the capillary is superimposed by a horizontal movement (vh) which is directed away from the already existing connection of the wire (3) to the chip and which continually decreases in relationship to the downward movement (vv).

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Unterageri, Switzerland

Marit Seidel