Sintering Copper Die-Bonding Paste Curable Under PressurelessConditions

Inhalt:
We have developed a sintering copper die-bonding paste curable at a temperature of over 225 °C in a H2 atmosphere under pressureless conditions. The die-shear adhesive strengths observed for Cu, Ni, Au, Ag, and Pd adherends were greater than 40 MPa. The thermal conductivity of the sintered copper die-bonding layer was 180 W/m·K, allowing rapid heat release. Scanning acoustic tomography (SAT) images did not indicate significant changes when the material was subjected to 1500 cycles of the thermal cycle test (TCT) at a temperature range between -40 and 200 °C. The sintered copper die-bonding has a thermal cycle reliability comparable to or better than sintered silver die-bonding or high-lead solder. This sintering copper die-bonding paste could be an ideal die-bonding material that is simultaneously fulfilled high thermal conductivity, high bonding reliability, reasonable cost, and applicability to mass production.