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Nano-porous carbon doped oxide (CDO) is one of the potential low dielectric constant (low-k) materials that can achieve a dielectric constant as low as 2.2 and is expected to be suitable for the next generation multilevel interconnection. However, the electrical stability of CDO in contact with metal has not been addressed. In this work, metal ions’ drift into nano-porous CDO is investigated. It is observed that both the Al and Cu ions can be driven into porous CDO film easily by applying electric field or thermal treatment. This results in a severe flat band voltage shift of the metal/CDO/Si capacitor structure. It is hypothesized that the lacking formation of self-limited aluminum oxide between Al and CDO film make Al ions drift into CDO. The adhesion of Al and Cu to CDO is also very poor. A physical model, combining weak dielectric polarization and metal ions drift, was proposed to explain the observed electrical instability. The inconsistent results regarding the Al/porous low-k/Si structure reported in the previous literatures can also be explained with this proposed model. Fortunately, TaN, as a common diffusion barrier material for Cu interconnect structure, is proved to have good adhesion to CDO. Negligible metal ions would drift in CDO during electrical stress. It is concluded that with a suitable diffusion barrier, such as TaN, CDO is still a very promising material for next generation Cu-interconnect technology. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study that investigated low-termperature reaction of thin-film platinum with silicon. Sheet resistance measurement of silicide formation sequence; Use nitrogen furnace; X-ray diffraction analysis.

Presents a technique based on the ion implantation of fluoride ion or species containing fluoride atoms into the silicon substrate underneath the platinum silicide (PtSi) layer. Function of PtSi; Material analysis of the PtSi under various annealing conditions; Silicide film characteristics.

Presents a study that formed a shallow silicided n[sup+]p junction by implanting arsenic ions into platinum or platinum silicide films followed by low-temperature furnace annealing in the nitrogen ambient. Benefits from implanting a dopant through metal/silicide; Reason that the ion implantation through metal sample exhibits smaller leakage than ion implantation through metal silicide sample; Annealing temperature dependence of the forward ideality factor.

Presents information on a study which examined proposed mechanisms on the role of fluorine in the thermal stability of silicide/silicon structures. Background of the study; Methodology of the study; Results and discussion.