W.J. Chen

ITO as a Diffusion Barrier Between Si and Cu

Indium tin oxide (ITO) thin films have been proposed as diffusion barriers for ultralarge scale integrated microelectronic devices. High-resolution transmission electron microscopy and electron diffraction showed that in the Cu/ITO/Si film, the 10 nm thick nanocrystalline ITO film layer works effectively as a barrier. Transmission electron microscopy, scanning electron microscopy, sheet resistance measurement, X-ray diffraction, and energy dispersive spectroscopy analyses revealed that ITO was found to be a good diffusion barrier against Cu at least up to 650°C. The failure temperature of ITO films diffusion barrier (10 nm) was 700°C. Our results show that ITO film can be considered as diffusion barriers for Cu metallization.

Growth Kinetics of Electroless Cobalt Deposition by TEM

The activation energy and initial growth of electroless cobalt thin films on silicon water has been studied by transmission electron microscopy (TEM). Electroless cobalt was deposited on Si(001) substrates after preactivation treatment. The electroless cobalt deposited initially nucleated into particles with different sizes and shapes, which coalesced together sequentially, and finally became a continuous film. The incubation period of Co-P deposit decreased when plating temperature increased from 65 to 90°C. The plot of film thickness vs. plating time was used to determine the plating rates. The plating rates increased when plating temperature increased from 65 to 90°C. The activation energy for the initial deposition of electroless Co-P film was 15.67 kcal/mol, which was calculated according to the Arrhenius equation.