R.F. bias effect on ECR plasma

An electron cyclotron resonance plasma is produced with a multislot antenna, where r.f. powers (13.56 MHz) are applied to a substrate. Plasma parameters measured with a probe are examined as a function of r.f. power and pressure. It is found that when the r.f. powers are applied, negative self-bias potential appears and the plasma density tends to decrease and the plasma potential increases. Furthermore, the effect of the negative self-bias potential on the radial profile of plasma parameters is discussed.