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New processes and materials are vital nowadays, since specific features of materials are essential to accomplish the more demanding technological and environmental requirements. Al/Ni system has stimulated a large number of phase equilibrium, thermodynamic, diffusion and related studies. Its relevance relays on first principle features as well as technological importance.Transient Liquid Phase Bonding(TLPB) process is presented in this work due to the advantages of this method above others. Low temperatures of processing are needed, to obtain stable intermetallic phases (IPs) suitable for high temperatures of service. The aim of this research is to investigate the impact of temperature on the IPs growth and formation mechanisms, completing previous works on microstructure and kinetics characterization of IPs in Al/Ni system at 720°C. The results of SEM-EDS/WDS analyses of the cross-sections of the bonds showed the presence of Al3Ni and Al3Ni2at the beginning of the interaction between Al and Ni, which are consistent with the phase equilibrium diagram. The Al3Ni2layer growth showed linear correlation with time at 800°C, whereas at 900 and 1000°C it suggested a diffusive growth. Inert markers experiments allowed distinguishing individual growth. Vickers micro-hardness was determined obtaining values for Ni and Al3Ni2of about 100 and 800 HV/ 0.025, respectively.

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The characterisation of diffusion soldered Cu/In/Cu interconnections is presented in this work. The main feature of this joining process is the production of a bond at a low fabrication temperature, which allows high service temperatures. The interconnection is formed entirely by intermetallic phases (IPs) which form isothermally rst by a liquid -solid reaction and then by a solid -solid reaction. The morphology and the growth kinetics of the IPs formed in the interconnection zone at temperatures in the range 180 -430°C were examined by electron probe microanalysis, X-ray diffraction and transmission electron diffraction analysis. In accordance with the phase diagram, the phases Cu 11 In 9 , Cu 2 In and Cu 7 In 3 (at T<310°C) and Cu 2 In and Cu 7 In 3 (at T>310°C) appeared in the interconnection zone. The thickness of the IPs formed during the solid -solid reaction obeyed a parabolic growth law. The growth rate constants were calculated for the Cu 2 In and Cu 7 In 3 phases. Using these values and the equilibrium concentration of the IPs, the integral interdiffusion coef cients were calculated through Wagner's approach.MST/5449