S i O₂Etching Using M= 0 Helicon Wave Plasma

Abstract

When applying high-density plasma to SiO2 etching, the ability to control the degree of dissociation is critical. In this study, two methods for controlling the degree of dissociation were evaluated using M=0 helicon wave plasma. One method was time-modulated discharge and the other adjusting the source power in the conventional continuous discharge. It was concluded that almost identical etching characteristics could be obtained, at least in M=0 helicon wave plasma, if and only if the applied source power in the continuous discharge was equal to the net source power in the time-modulated discharge. The probe measurement revealed that the electron temperature did not change with increasing source power; however, the emission spectroscopic study indicated that the high-energy tail of the electron-energy distribution function grew with increasing source power. This is considered to be the cause of the high degree of dissociation.

Numerical analysis of the pressure dependence of the etch rate in an Al etching reactor equipped with a helicon source

“…4 Under typical etching conditions, the etch rate increased as pressure increased in the low-pressure region below 10 mTorr. First, we look at our experimental data, which were obtained using an Al etching reactor equipped with a helicon plasma source.…”

etching byM= 0 helicon plasma

“…Parts of this paper are quoted from our previous articles [4,5] in order to give a unified explanation.…”