• Current researchers: Mike Cuddy
• Related Fisher group references:
  • Comparison of Pulsed and Continuous Wave Deposition of Thin Films from C2F6/H2 and CF4/H2 Inductively Coupled rf Plasmas, Neil M. Mackie, N.F. Dalleska, David G. Castner, and Ellen R. Fisher, Chem. Mater. 9, 349-362 (1997).
  • Surface Reactivity of CF2 Radicals using LIF and C2F6 Plasma Molecular Beams N. M. Mackie, V. A. Venturo, and E. R. Fisher, J. Phys. Chem. 101, 9425-9428 (1997).
  • Characterization of Pulsed Plasma Polymerized Aromatic Films N. M. Mackie, David G. Castner, and E. R. Fisher, Langmuir 14, 1227-1235 (1998).
  • Surface Interactions of CF2 Radicals During CHF3 Plasma Treatment of Polymeric and Metallic Substrates N. E. Capps, N. M. Mackie, and E. R. Fisher, J. Appl. Phys. 84, 7618-7626 (1998).
  • Control of Surface Film Composition and Orientation with Downstream PECVD of Hexafluoropropylene Oxide C. I. Butoi, N. M. Mackie, J. E. Barnd, E. R. Fisher, L. J. Gamble and D. G. Castner, Chem. Mater. 11, 862-864 (1999).
  • Deposition of Highly Ordered CF2-Rich Films using CW and Pulsed Hexafluoropropylene Oxide Plasmas C. I. Butoi, N. M. Mackie, L. J. Gamble, D. G. Castner, A. M. Miller, J. E. Barnd, and E. R. Fisher, Chem. Mater. 12, 2014-2024 (2000).
  • Ion and Substrate Effects on Surface Reactions of CF2 using C2F6, C2F6/H2 and Hexafluoropropylene Oxide Plasmas C. I. Butoi, N. M. Mackie, K. L. Williams, N. E. Capps, and E. R. Fisher, J. Vac. Sci. Technol. A, 18, 2685-2698 (2000).
  • Comparison of CH, C3, CHF, and CF2 Surface Reactivities During Plasma-Enhanced Chemical Vapor Deposition of Fluorocarbon Films. D. Liu, M.F. Cuddy, E.R. Fisher, ACS Appl. Mater. Interfaces, 1, 934-943 (2009).

Fluorinated polymeric materials have generated interest as possible low-k dielectric constant materials for applications in the semiconductor industry. Our work in this area has focused on understanding the deposition of fluorinated polymers from continuous wave (CW) plasmas with CF4 and C2F6 precursors. A balance between etching and deposition occurs during substrate processing that can be tuned with the addition of H2 (to promote film deposition) or O2 (to promote etching).

An increasingly popular trend in the semiconductor industry has been to explore the nature of transition metal oxides for use in nanoscale semiconductive materials. To this extent, we have investigated plasma-surface interactions for both Si and ZrO2 substrates. We are able to model the internal energies for CFx (x = 1-3) species in these systems using optical emission spectroscopy (OES) and laser induced fluorescence spectroscopy and can monitor relative concentrations by actinometry.

Additional characterization techniques used in this research include mass spectrometry (MS), and IRIS studies (click here for more about our mass spectrometer and IRIS technique). Our mass spectrometer was recently upgraded and equipped with the capability to scan a wide range of ion energies, enabling acquisition of data to describe the energy of CFx ions in FC plasmas.

IRIS experiments have focused on the behavior of CF and CF2 radicals in the aforementioned systems. The most notable aspects of these results are that the steady-state surface reactivity of CF2 changes significantly with plasma feed gas composition, the surface reactivities are substrate-dependent, and under some conditions the deposited polymer film is ablated during plasma processing. For example, in our IRIS experiments, we observe a CF2 scattering coefficient (S(CF2)) greater than unity for processing of Si, indicating surface production of the CF2 molecule, while S(CF2) < 1 for ZrO2 substrate processing.