FLUOROCARBON HIGH-DENSITY PLASMA .6. REACTIVE ION ETCHING LAG MODEL FOR CONTACT HOLE SILICON DIOXIDE ETCHING IN AN ELECTRON-CYCLOTRON-RESONANCE PLASMA

Etching of high aspect ratio patterns induces reactive ion etching (RI E) lag. This effect is studied for oxide features etched in a high den sity plasma excited by electron cyclotron resonance using different fl uorocarbon gases. A new RIE lag model is proposed which depends on the assumption that the oxide etch rate is, as on a blanket sample, stron gly influenced by the deposition of fluorocarbon film on the oxide sur face during the etching process.