High Temperature Oxidation Of Cu-Al Or Cu-Mg Dilute Alloys

In recent years, the research on oxidation at high temperature has been broadened with development of relevant subject and new technology. The research area has been enlarged from the traditional metals to all kinds of materials in other areas. The oxidation reaction velocity quickly increased quickly with the temperature increasing. Then, the ability of corrosive resistance becomes a serious problem. With the development of the modern technology, the metallic material must have good mechanical properties and oxidation resistance ability. The diversiform circumstance suggests that is complex. Under some conditions, the ability of corrosive resistance has baffled the development of the new technology. So we must search new materials and methods to prevent Cu from corrosion, for example, intermetallic compound, composite materials and nanomaterials.Cu is traditionally employed as cooling devices, including water-cooled Cu fingers, panels and tadpoles, due to its high strength and high thermal conductivity at elevated temperature. Nowadays, Cu is also the also the most important metallization material for ultralarge scale integrated circuits (USIC) as interconnects due to its excellent electric conductivity and superior electro/stress-migration resistance.This paper studied the oxidation behaviors of Cu-Mg and Cu-Al alloys at high temperature by annealing in H2 or Ar atmosphere. Scanning electronic microscope (SEM), electron probe miscroanalyzer (EPMA) and secondary ion mass spectroscopy (SIMS, UHVAC-PHI SIMS600) were used to investigate the morphology and distribution of Cu, Al, Mg and O over the annealed specimens. X-ray diffraction (XRD) was used to identify the phases on the surface of samples after annealing.We can draw the conclusions as follow: 1 After annealing MgO layer is formed on the surface of Cu-Mg alloy, which is flat and adherent.2 The ability of oxidation resistance of CuMg at low temperature is better than pure Cu. But at high temperature, because of localized segregation form MgCu2 the ability of oxidation resistance is weakened.3 Cu-0.2Al alloy was annealed with three different annealing ways, the Al₂O₃ layer formed on the surface. The ability of oxidation resistance is better than 6N Cu.4 For Cu-0.2Al alloy annealed at H2 atmosphere, annealing at high-temperature and with slow cooling results in flat, dense and adherent Al₂O₃ surface layer. High-temperature annealing also enhances formation of thicker Al₂O₃ surface.5 For Cu-0.2Al alloy in Ar atmosphere, a flat, dense and adherent Al₂O₃ surface layer can only be formed for annealing at low temperature and rapid cooling, while higher temperature annealing at Ar atmosphere leads to surface Cu oxidation and peeling off of the Al₂O₃.6 Cu-0.2Al alloy annealed at H2 atmosphere annealing is better than Cu-0.2Al alloy at Ar atmosphere annealing. While higher temperature annealing at Ar atmosphere leads to surface Cu oxidation and peeling off of the Al₂O₃ layer, even though slow cooling will lead to peeling off of the Al₂O₃ layer.7 The surface oxide layer of Cu-Al 0.2 alloy H2 atmosphere annealing is better than that of Cu-Mg alloy H2 atmosphere annealing.