Chemical Etching of Silicon Assisted by Graphene Oxide in an HF–HNO₃ Solution and Its Catalytic Mechanism

Chemical etching of silicon assisted by various types carbon materials is drawing much attention for the fabrication micro/nanostructures. We developed a method chemical that utilizes graphene oxide (GO) sheets to promote reaction in hydrofluoric acid–nitric acid (HF–HNO3) etchant. By using an optimized composition HF–HNO3 etchant, rate under GO was 100 times faster than our HF–H2O2 system used previous report. Kinetic analyses showed activation energy almost same at both bare and GO-covered areas. propose adsorption sites reactant enhance frequency, leading deeper areas Furthermore, with more defects were found have higher catalytic activities. This suggests function as reactant, thereby enhancing sheets.