A supercritical etching composition and method for etching an inorganic material of a semiconductor-based substrate are provided. The method includes providing a semiconductor-based substrate having an exposed inorganic material and exposing the substrate to the supercritical etching composition, whereby exposed inorganic material is removed from the substrate. In one embodiment, the supercritical etching composition includes a supercritical component, which is not capable of etching a particular exposed inorganic material, and a nonsupercritical etching component, which is capable of etching the particular exposed inorganic material. In another embodiment, the supercritical etching composition includes a supercritical component, which is capable of etching the particular exposed inorganic material.