Room Temperature KlettWelding Interconnect Technology for High Performance CMOS Logic

In this work we report a novel room temperature bonding technology based on metallic NanoWires, so-called KlettWelding. This technology can be used for bonding Flip-Chips with down to 5 μm edge length bumps and fine pitches less than 8 μm. The process is expected to work for die to wafer (d2w) or wafer to wafer (w2w) bonding. The required bonding pressures range from 1 to 15 MPa for flip chips, Diodes, IGBT, MOSFETS, μC, Video chips, LEDs and sensors. The measured shear strength of these connections yields 15 to 60 MPa. Such contacts have shown in the first results a high thermal conductance in the range of 350 W/mK. Also, the connections can tolerate temperatures higher than 500 °C.