Low-energy high flux reactive ion etching by rf magnetron plasma

Abstract

The magnetron plasma etching of SiO2 and Si in fluorocarbon gas has been investigated. The plasma has high ionization degree, collisionless high density, and low energy ion flux (I∼1.0 mA/cm2, 30≲Ei ≲250 eV at 1 W/cm2) and a controllable etch uniformity. The bulk of the plasma supports an electric field which can be shaped to achieve normal ion bombardment of the etching surface. Good etching anisotropy, high SiO2/Si selectivity, and rates six times greater than conventional reactive ion etching were demonstrated.