Applied Science and Convergence Technology 2014; 23(4): 169-178
Published online July 30, 2014
Copyright © The Korean Vacuum Society.
Graduate Program of Plasma Convergence Engineering & Plasma Materials Research Center,
Kunsan National University
Correspondence to:Junghoon Joo*
Fluid model based numerical analysis is done to simulate a low damage etch back system
for 20 nm scale semiconductor fabrication. Etch back should be done conformally with very
high material selectivity. One possible mechanism is three steps: reactive radical generation,
adsorption and thermal desorption. In this study, plasma generation and transport steps are
analyzed by a commercial plasma modeling software package, CFD-ACE+. Ar + CF4 ICP
was used as a model and the effect of reactive gas inlet position was investigated in 2D
and 3D. At 200∼300 mTorr of gas pressure, separated gas inlet scheme is analyzed to work
well and generated higher density of F and F2 radicals in the lower chamber region while
suppressing ions reach to the wafer by a double layer conducting barrier.
Keywords: numerical modeling, inductively coupled plasma, etch back, gas inlet position, CFD-ACE+