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Interdiffusion coefficients have been measured in Cu–Pd alloys containing 70–90 at.% Pd at temperatures from 355° to 440°C using films containing short wavelength composition modulations produced by evaporation. From the relative intensities of the high- and low-angle satellites about the 111 Bragg peak, it was established that the composition modulations were coherent for λ<28 Å (where λ is the wavelength of the modulation) and were incoherent for λ>38 Å. Over the range 28 to 38 Å, there was a progressive loss in coherency and this was accompanied by a twofold decrease in the diffusivity. This decrease confirms quantitatively the effect of coherency strains on diffusion predicted by Cahn. The dependence of the effective diffusion coefficient on wavelength in the coherent modulations yielded K=−10.3×10−6 erg·cm−1 for the gradient-energy coefficient.

The surface of aluminum metallization on silicon devices can reconstruct with elevated temperature treatments due to the relief of compressive stresses induced by thermal expansion differences between aluminum and silicon. This reconstruction can cause reliability problems because of the development of thin regions in the metal. Also, in multilayer circuits, hillocks can punch through the-oxide layer and cause electrical shorts. In this paper the surface reconstruction is categorized into two modes: high temperature--few cycles (device processing) and low temperature--many cycles (device operation). Mechanisms for each of these reconstruction modes are postulated and suggestions for reducing or eliminating this effect Are made.

Mg-doped Ba0.96Ca0.04Ti0.84Zr0.16O3 (BCTZ) thin films have been proposed as a promising material for microelectronic device applications based on high dielectric materials. Perovskite polycrystalline Mg-doped BCTZ thin films were fabricated on a Pt/Ti/SiO2/Si substrate by metalorganic decomposition method. Dielectric properties were improved after a Pt/Mg-doped BCTZ thin film/Pt capacitor was post-annealed at 700 °C in O2 atmosphere for 30 min. A high dielectric constant of 460 at 1 MHz, a low dissipation factor less than 4.5%, and a low leakage current density of 4×10−7 A/cm2 at 3 V were obtained. Improved dielectric properties were discussed in conjunction with reduction of oxygen vacancies and electrons due to the post-annealing and Mg dopants.

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