Development of controlling the self-bias voltage and its appraisal by means of estimating ion damages

摘要

Abstract: s on discussing a method to reduce the self-biasvoltage and applying this method to a plasma etcher toimprove reduction of ion damages. We have developed atechnique that can reduce the self-bias voltage withoutdisturbing the main plasma by using a supplementalelectron flow from the powered electrode to the plasmathrough the sheath. We have concluded experimentallythat the effects of the supplemental electron flow onthe main plasma parameters is not serious and damageinduced to films is reduced considerably. Theexperiments were carried out in an rf dischargechamber. It may be certain from the results that thedisturbance on the plasma parameters created by thevariable self-bias voltage is minimal. The damage tothe films induced by its ion bombardment is reduced byapproximately one-half, when the self-bias voltage wascontrolled from $MIN@120 V to $MIN@98 V. !5