Thermo-sonic/Ultra-sonic Bonding – Gold stud-bumped die bonding

Copper pillar bumps after reflow

Gold stud bump on a bond pad. Diameter at base about 75 microns

NASA implantable fetal monitor, five flipped chips. Board 30 mm long, 10 mm wide. (NASA Photo)

Closer view of two flipped chips in NASA fetal monitor

Copper bumps with reflowed eutectic solder caps (courtesy TMLI Corporation)

Stacked, dipped double gold stud bumps. (MKPA photo)

Jetted double solder bumps from Pac Tech SBB2. (Pac Tech photo)

25 micrometer thinned Gallium Arsenide wafer. (Fraunhofer-Institut IZM photo)

3-D RAM, with four 64 Meg chips on a folded flex substrate. In the foreground is a single 64 Meg packaged ram.

Conductive adhesive stencilled onto a bond pad. Pad dimemensions about 75 microns.

Gold stud bump after dipping in conductive adhesive. Diameter at base about 75 microns.

Gold stud bump connection from chip (top) to substrate. Conductive adhesive around the bump, non-conductive underfill beyond.

Electroless nickel – gold under-bump metal (UBM) on wafer. (Pac Tech photo)

Reflowed solder bumps on electroless nickel-gold UBM. (Pac Tech photo)

Molded underfill (MUF) preforms.

Stacked gold stud bumps, 17 high. A new world record! (N. Ishikawa, Fujitsu Ltd.)

The Great Wall of Bumps, 1 to 15 (N. Ishikawa, Fujitsu Ltd.)