Sintering of nanosilver paste had been extensively studied as a lead-free die-attach solution for bonding semiconductor chips. In this paper, we developed a rapid way to sinter nanosilver paste for bonding insulated-gated-bipolartransistor (IGBT) using pulsed current. In this way, we firstly dried as-printed paste at 100 deg C in order to get rid of many volatile solvents that may form defects or voids during the outgassing of the paste. Then the dried paste was further heated by pulse current ranging from 1 kA to 2 kA for several seconds. The whole procedure was less than 5 min. We could obtain robust sintered die attachment for (1200V, 25A) IGBT from ABB (SIGC32T120R3LE) in a rapid way by pulsed current. The dieshear strength of the die attachment could reach up to 25-30 MPa. The cross-sectional morphology of the sintered die attachment was characterized by scanning electron microscopy. It was concluded that the current-assisted way could be used to sinter nanosilver paste rapidly for bonding real IGBT chips. This good news may benefit the wide usage of nanosilver paste in the future.
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