Antenna charging effects on the electrical characteristics of polysilicon gate during electron cyclotron resonance etching

Abstract

The nonuniformity of the induced leakage current in metal oxide semiconductor (MOS) capacitors has been investigated in an electron cyclotron resonance (ECR) system. For plasma-etched MOS capacitors with 5-nm-thick oxides, it is found that the leakage currents induced by plasma etching increase with increasing overetching time. However, additional E(bd) (breakdown held) degradation is not obvious as overetching percentage increases from 10% to 50%. A mechanism based on the antenna charging effect has been proposed to explain the E(bd) electrical characteristics. In accordance with the mechanism, the E(bd) degradation has been significantly reduced by first etching off a narrow peripheral edge around the gate pattern.