For the application of In-49Sn solder in bonding recycled-sputtering targets to Cu back plates, the intermetallic compounds formed at the In-49Sn/Cu interface are investigated. Scanning electron microscopy (SEM) observations show that the interfacial intermetallics consist of a planar layer preceded by an elongated scalloped structure. Electron-probe microanalyzer analyses indicate that the chemical compositions of the planar layer and the scalloped structure are Cu 74.8 In 12.2 Sn 13.0 and Cu 56.2 In 20.1 Sn 23.7 , respectively, which correspond to the ε-Cu 3 (In,Sn) and -Cu 6 (In,Sn) 5 phases. Kinetics analyses show that the growth of both intermetallic compounds is diffusion controlled. The activation energies for the growth of -and ε-intermetallics are calculated to be 28.9 kJ/mol and 186.1 kJ/mol. Furthermore, the formation mechanism of intermetallic compounds during the In-49Sn/Cu soldering reaction is clarified by marking the original interface with a Ta-thin film. Wetting tests are also performed, which reveal that the contact angles of liquid In-49Sn drops on Cu substrates decline to an equilibrium value of 25°C.

The Sn-8Zn-3Bi (wt.%) solder was prepared by encapsulating pure Sn (99.9%), Zn (99.

The incidence of aortic infection in patients with non-typhoid Salmonella bacteraemia was high in Taiwan. Timely surgical intervention and prolonged intravenous antibiotic therapy resulted in excellent outcomes.

The interfacial reactions between In49Sn solders and Ag thick films at temperatures ranging from 200°C to 350°C have been studied. The intermetallic compound formed at the Ag/In49Sn interface is Ag 2 In enveloped in a thin layer of AgIn 2 . Through the measurement of the thickness decrease of Ag thick films, it has been determined that the reaction kinetics of Ag 2 In has a linear relation to reaction time. Morphology observations indicated that the linear reaction of Ag 2 In was caused by the floating of Ag 2 In into the In49Sn solder as a result of the In49Sn solder penetrating into the porous Ag thick film. A sound joint can be obtained when a sufficient thickness of the Ag thick film (over 19.5 m) reacts with the In49Sn solder. In this case, the tensile tested specimens fracture in the In49Sn matrix.

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