The fabrication of metal tips involves various methods, including chemical etching, electrochemical etching, and focused ion beam (FIB) milling. Each technique has its advantages and limitations:
Chemical etching: Involves dissolving metal in a chemical solution to achieve a sharp tip. It is relatively simple and cost-effective but can lack precision. Electrochemical etching: Uses an electric current to etch the metal, providing better control over the tip shape and sharpness. Focused ion beam (FIB) milling: Employs a beam of ions to sculpt the metal into a tip with excellent precision. This method is more expensive and complex but yields high-quality tips.
