LAUSR

A fluid model is employed to investigate the effect of radio frequency bias on the behavior of an argon inductively coupled plasma (ICP). In particular, the impact of ICP source power, single-frequency bias power, and dual-frequency bias power on the characteristics of ICP is simulated at a fixed pressure of 30 mTorr. When the bias frequency was fixed at 27.12 MHz, the two-dimensional (2D) plasma density profile was significantly affected by the bias power at low ICP source power (e.g., 50 W), whereas it was weakly affected by the bias power at higher ICP source power (e.g., 100 W). When dual-frequency (27.12 MHz/2.26 MHz) bias was applied and the sum of bias powers was fixed at 500 W, a pronounced increase in the maximum argon ion density was observed with the increase in the bias power ratio in the absence of ICP source power. As the ratio of 27.12 MHz/2.26 MHz bias powers decreased from 500 W/0 W to 0 W/500 W with the ICP source power fixed at 50 W, the plasma density profiles smoothly shifted from edge-high to center-high, and the effect of bias power on the plasma distribution became weaker with the decrease in the bias power ratio. Besides, the axial ion flux at the substrate surface was characterized by a maxima at the edge of the substrate. When the ICP source power was higher, the 2D plasma density profiles, as well as the spatiotemporal and radial distributions of ion flux at the substrate surface were characterized by a peak at the reactor center, and the distributions of plasma parameters were negligibly affected by the dual-frequency bias power ratio.