Abstract
Fluorinated amorphous carbon thin films (a-C:F) for use as low-dielectric-constant interlayer dielectrics are deposited by helicon-wave plasma enhanced chemical vapor deposition. To improve their thermal stability, the feasibility of adjusting the fluorine-to-carbon (F/C) ratio by changing the deposition pressure was investigated. Decreasing the pressure increased the dissociation of a source fluorocarbon material in the plasma and decreased the F/C ratio of the deposited film. Both the thermal stability and the dielectric constant of the a-C:F films were increased as the F/C ratio was decreased. Thus, there is a tradeoff relationship between a low dielectric constant and high thermal stability and the tradeoff could be optimized by the pressure during deposition. The mechanism of the pressure dependency of the dielectric constant of a-C:F films was investigated by quantifying the contribution of each polarization and found that a decrease in the dielectric constant of a-C:F films can be attributed to decreases in the orientational and electronic polarizations.
Original language | English |
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Pages (from-to) | 2739-2745 |
Number of pages | 7 |
Journal | Journal of Applied Physics |
Volume | 86 |
Issue number | 5 |
DOIs | |
Publication status | Published - 1999 Sept |
Externally published | Yes |
ASJC Scopus subject areas
- Physics and Astronomy(all)