Porous Chip Collet Pressure Control for Uniform Semiconductor Bonding

The bottom surface of the collet is divided into multiple ventilation holes distributed across different regions. This segmentation allows negative pressure to be applied uniformly across the entire chip surface through multiple discrete openings, preventing the formation of large pressure differentials that cause non-uniform pressing. The segmented structure maintains reliable chip holding while eliminating the boundary effect between positive and negative pressure zones.

Different regions of the collet bottom surface are equipped with ventilation holes of specific sizes and distributions tailored to local requirements. The ventilation holes are strategically positioned to ensure uniform negative pressure distribution across the chip surface, with particular attention to edge regions to prevent gap formation. This localized optimization achieves both stable holding and uniform pressing.

The single second ventilation hole for positive pressure injection is divided into multiple smaller holes distributed across the central region. This segmentation prevents rapid pressure buildup and reduces the intensity of pressure changes at boundaries. The distributed positive pressure application suppresses air entrainment and void formation while minimizing vibrations caused by sudden pressure transitions.

A porous plate member is introduced as an intermediary between the positive pressure source and the chip surface. The porous structure gradually distributes the positive pressure across multiple small openings, acting as a buffer that smooths pressure transitions. This intermediary prevents direct, rapid pressure injection that causes vibrations while still effectively suppressing air entrainment and voids.