Effects of Ar addition on breakdown voltage in a Si(CH3)2(OCH3)2 RF discharge

We present detailed measurements on breakdown voltage (V_f) in a RF discharge with Si(CH₃)₂(OCH₃)₂ gas diluted with Ar. When Ar concentration (P_Ar) is increased, the V_f gradually decreases up to P_Ar = 50 %, and then is followed by a drastic decrease. The P_Ar dependence of V_f is well explained by a feature of the ion-induced secondary electron emission coefficient (γ) deduced from measured Paschen curves. A drastic increase in Ar ion flux with P_Ar induces high emission of electrons from cathode surface, resulting in lowing V_f.