“…The oxidation distance was measured to be approximately 10 m for Sn-9Zn-2Ag alloys and 30 m for Sn-9Zn-4Cu alloys. It is known that the oxidation resistance of the Sn-Zn eutectic and Sn-8Zn-3Bi pastes is poor for the joining of QFP or 1608R chips to Cu electrodes during thermal and humidity exposure [18,28]. According to recent reports [18], the oxidation rate of the Sn-Zn eutectic alloy is much slower than that of the Sn-8Zn-3Bi alloy under the same conditions; the oxidation distance is 70 and 130 m after 1000 h exposure, respectively.…”