Hostname: page-component-5c6d5d7d68-7tdvq Total loading time: 0 Render date: 2024-08-22T08:27:36.368Z Has data issue: false hasContentIssue false

Nano-Scale Morphology and Electron Spectrum of Defect States in Low-k SiOCH Films

Published online by Cambridge University Press:  11 February 2011

V. Ligatchev
Affiliation:
School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, SINGAPORE
T.K.S. Wong Rusli
Affiliation:
School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, SINGAPORE
B. Liu
Affiliation:
School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, SINGAPORE
K. Ostrikov
Affiliation:
School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, SINGAPORE
Get access

Abstract

Results of experimental investigations on the relationship between nanoscale morphology of carbon doped hydrogenated silicon-oxide (SiOCH) low-k films and their electron spectrum of defect states are presented. The SiOCH films have been deposited using trimethylsilane (3MS) - oxygen mixture in a 13.56 MHz plasma enhanced chemical vapor deposition (PECVD) system at variable RF power densities (from 1.3 to 2.6 W/cm2) and gas pressures of 3, 4, and 5 Torr. The atomic structure of the SiOCH films is a mixture of amorphous-nanocrystalline SiO2-like and SiC-like phases. Results of the FTIR spectroscopy and atomic force microscopy suggest that the volume fraction of the SiC-like phase increases from ∼0.2 to 0.4 with RF power. The average size of the nanoscale surface morphology elements of the SiO2-like matrix can be controlled by the RF power density and source gas flow rates.

Electron density of the defect states N(E) of the SiOCH films has been investigated with the DLTS technique in the energy range up to 0.6 eV from the bottom of the conduction band. Distinct N(E) peaks at 0.25 - 0.35 eV and 0.42 - 0.52 eV below the conduction band bottom have been observed. The first N(E) peak is identified as originated from E1-like centers in the SiC-like phase. The volume density of the defects can vary from 1011 - 1017 cm-3 depending on specific conditions of the PECVD process.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

References

REFERENCES

1. Peters, L., Semicond Int., 64, 64 (1998).Google Scholar
2. Dielectric materials and applications / Von Hippel, A.R, Boston: Artech House, 1995, 438 p.Google Scholar
3. Ligatchev, V., Wong, T.K.S., Liu, B, Rusli, , J. Appl. Phys., 92, 4605 (2002).Google Scholar
4. Ligatchev, V., Yoon, S.F., Ahn, J., Zhang, Q., Rusli, , Rad. Eff. Def. Sol., 154, 261 (2001).Google Scholar
5. Sugahara, S., Kadoya, T., Isami, K.-I. et al., J. Electrochem. Soc., 148, F120 (2001).Google Scholar
6. Wilhelm, M., Kubel, F.. Wruss, W., Powder Diffraction, 16, 42 (2001).Google Scholar
7. OPCOMC, Donohue, duPont de Nemours and Company, Delaware, USA (1967).Google Scholar
8. X-ray diffraction procedures for Polycrystalline and Amorphous Materials / Klug, H.P., Alexander, L.E.. John Wiley, N.Y., 1974, 966 p.Google Scholar
9. Johnson, N.M, Bartelink, D.J., McVittie, J.P., J. Vac. Sci. Technol., 16, 1407 (1979).Google Scholar
10. Mnatsakanov, T.T., Pomorceva, L.I., Yurkov, S.N., Semiconductors, 35, 394 (2001).Google Scholar
11. Lebedev, A.A., Semiconductors 33, 2, 107130 (1999).Google Scholar
12. Rybicki, G.C., J. Appl. Phys., 78, 2996 (1995).Google Scholar