Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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High rate dry etching of Si in fluorine-based inductively coupled plasmas

  • Cho, Hyun (Department of Materials Engineering, Miryang National University) ;
  • Pearton, S.J. (Department of Materials Science and Engineering, University of Florida, Gainesville)
  • Published : 2004.10.01
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Abstract

Four different Fluorine-based gases ($SF_6/,NF_3, PF_5,\; and \; BF_3$) were examined for high rate Inductively Coupled Plasma etching of Si. Etch rates up to ~8$\mu\textrm{m}$/min were achieved with pure $SF_6$ discharges at high source power (1500 W) and pressure (35 mTorr). A direct comparison of the four feedstock gases under the same plasma conditions showed the Si etch rate to increase in the order $BF_3$ < $NF_3$< $PF_5$ < $SF_6$. This is in good correlation with the average bond energies of the gases, except for $NF_3$, which is the least strongly bound. Optical emission spectroscopy showed that the ICP source efficiently dissociated $NF_3$, but the etched Si surface morphologies were significantly worse with this gas than with the other 3 gases.

Keywords

References

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