Process optimization of inductively coupled plasma etching for large aspect ratio silicon nanopillars

Deep Reactive Ion Etching (DRIE) process on Si to achieve nanopillar arrays with large aspect ratio by using hydrogen silsesquioxane (HSQ) as etching masks has been systematically studied. Parameters in etching process such as coil power, platen power and gas flow have been optimized. The lateral etching has been reduced and the verticality has been controlled better. Under the optimized condition, 13.3 μm high Si nanopillars with good verticality, low roughness and the aspect ratio up to 36 (height/FWHM) were fabricated. And Si nanopillars with different sidewall profile, size and height were obtained using different etching conditions.

Duke Scholars

Author Xin Li Electrical and Computer Engineering