Very high frequency capacitively coupled discharges for large area processing

A two-dimensional fluid model is used to study the characteristics of a capacitively coupled discharge system at drive frequencies of 13.56-100 MHz. Results are presented for a large reactor that can accommodate 300 mm wafers. The plasma density and ion flux scale approximately as the square of the frequency at constant applied voltage which agrees well with measurements. The rf current, ionization rate, and sheath thickness also scale favorably with frequency. The simulations reveal that the plasma and ion characteristics are uniform across the electrode except near the edge. (C) 1996 American Vacuum Society.