Modeling of a-Si : H deposition in a DC glow discharge reactor

Authors

Dariusz Orlicki, Laboratory for ceramic and reaction engineering, Department of chemical engineering, State University of New York at Buffalo, New York, 14260.
Vladimir Hlavacek, Laboratory for ceramic and Reaction Engineering, Department of chemical Engineering, State University of New York at Buffalo, New York.
Hendrik J. Viljoen, University of Nebraska-LincolnFollow

Date of this Version

8-1-1992

Comments

Published in Journal of Material Research, Vol. 7. No. 8, pp. 2160 - 2181, Aug 1992. © 1992 Materials Research Society. This article can also be viewed at the Journal home page

Abstract

PECVD reactors are increasingly used for the manufacturing of electronic components. This paper presents a reactor model for the deposition of amorphous hydrogenated silicon in a dc glow discharge of Ar-SiH₄ The parallel-plate configuration is used in this study. Electron and positive ion densities have been calculated in a self-consistent way. A macroscopic description that is based on the Boltzmann equation with forwardscattering is used to calculate the ionization rate. The dissociation rate constant of SiH₄ requires knowledge about the electron energy distribution function. Maxwell and Druyvesteyn distributions are compared and the numerical results show that the deposition rate is lower for the Druyvesteyn distribution. The plasma chemistry model includes silane, silyl, silylene, disilane, hydrogen, and atomic hydrogen. The sensitivity of the deposition rate toward the branching ratios SiH₃ and SiH₂ as well as H₂ and H during silyl dissociation is examined. Further parameters that are considered in the sensitivity analysis include anode/cathode temperatures, pressure, applied voltage, gap distance, gap length, molar fraction of SiH₄, and flow speed. This work offers insight into the effects of all design and control variables.