The characteristics of the UHF (Ultra-High-Frequency) plasma and SiO 2 etching with this plasma source were investigated. A study on the optical emission spectroscopy shows that the plasma abounded in CF 2 radicals, which indicates that the degree of the dissociation of feed gas is low. The ion saturation current density shows low dependence on pressure. The etching characteristics, such as SiO 2 etch rate and RIE lag, also show low dependence on pressure. There is no significant effect of pressure on etched profile for a given ion saturation current density, a self-bias voltage and a selectivity of SiO 2 to Photoresist (PR). These characteristics demonstrate that the UHF plasma source can be expected to provide a wide process window for pressure.
|Title of host publication||NEC Research & Development|
|Number of pages||8|
|Publication status||Published - 1997 Apr 1|
ASJC Scopus subject areas