Numerical simulation of local charging during plasmaetching of a dielectric material

Aspect ratio independent etching of dielectrics

“…Arnold and Sawin 6 found a precipitous drop in the potential at the trench middle and speculated that the trench bottom will evolve to be concavelike. In contrast, Shibkov et al 7 calculated a potential distribution that peaks in the trench middle, suggestive of a convex trench bottom. Joubert et al 8 showed that both shapes of the bottom contours are observed, albeit as a result of the specific etch-inhibiting chemistry employed rather than charging effects.…”

“…Two theoretical studies 6,7 addressed the localized charging in rectangular trenches with profound differences in the calculated potential distribution along the trench surfaces. Arnold and Sawin 6 found a precipitous drop in the potential at the trench middle and speculated that the trench bottom will evolve to be concavelike.…”

Relationship between edge roughness in mask pattern and charging in plasma etching

“…These defects may get worse with increasing demand for high aspect ratio which is still a challenge to the semiconductor industry; on the other hand, charging may develop the voltage which could provoke breakage of thin gate oxide films. The requirement for overcoming these artifacts has attracted a large number of theoretical and experimental studies on the charging effect. However, almost all of them only focused on the charging problem on the profile of a trench, except for our previous studies .…”

A hybrid modeling framework for simulating plasma-surface interactions of rough polymeric substrates

“…This is enough to conclude that the thickness does not affect the etching rate. Although the effect of the dielectric thickness on charging time has not been studied before either in conventional or unconventional surface morphologies, the charging time in microtrenches has been calculated in previous works and has been also found to lie in the range of ms [132,133,139,146,163,164,222]. Moreover, the charging time is much smaller than the time required for a remarkable change of the surface morphology during plasma etching; indeed, for such a short time period (e.g.…”

“…The need to remedy these artifacts has been the motive for several theoretical and computational studies on surface charging. The majority of them focus on dielectric, mainly Silicon dioxide Twisting Etching lag (SiO2) trenches or holes [130][131][132][133][134][135][136][137][138][139][140][141], some of them on Si trenches with a dielectric mask [142][143][144] and/or on SOI wafers [120,145,146].…”