Folded Wire Loop Bonding for Semiconductor Interconnections

The bonding structure is segmented into multiple functional portions: a ball bonding portion for initial connection, a wire loop for electrical connection, and a stitch bonding portion with folded portions for enhanced adhesion. This segmentation allows each portion to perform its specific function optimally, resolving the contradiction between strength and complexity.

The bonding approach transitions from a simple linear wire connection to a multi-dimensional folded structure. The first and second folded portions create a three-dimensional configuration that increases contact area and bonding strength without significantly increasing horizontal space occupation, thus improving strength while controlling complexity.

The bonding apparatus employs dynamic trajectory control to automatically form the complex folded portions. The stitch bonding process uses a programmed overlapping trajectory that dynamically moves the bonding tool through specific paths (first upward direction, first downward diagonal direction, second upward direction, second downward diagonal direction) to create the folded structure, making the complex process controllable and repeatable.

The wire loop structure itself serves multiple functions: it provides electrical connection, mechanical support, and the folded portions automatically create the enhanced bonding interface. The tail end protruding from the second folded portion provides additional bonding capability, allowing the structure to self-reinforce without requiring separate additional components or processes.