Atomic surface manufacturing based on plasma-induced atom-selective etching

Manufacturing is developing from Manufacturing I, based on empirical skills, and Manufacturing II, based on classical theory, to Manufacturing III, based on quantum theory. Although these three manufacturing paradigms appear at different historical stages, they will coexist, and Manufacturing II will still play a leading role for the foreseeable future. The core area of Manufacturing III will be atomic and close-to-atomic scale manufacturing (ACSM), covering manufacturing accuracy, feature dimensions, and the scale of material removal, migration, and addition. The manufacturing of atomic surfaces is an important area for the development of ACSM. This article will introduce a novel atomic surface fabrication technique named plasma-induced atom-selective etching (PASE). The atoms on the rough surface of a single-crystal material have different bonding states and therefore have different priorities during plasma etching. These reaction priorities can be modulated by changing the radicals, concentration, and temperature of the plasma. Hence, PASE could selectively remove the excess atoms on the single-crystal material surface and eventually achieve an atomic surface. PASE has been successfully applied to many hard and brittle materials, including Si, SiC, and Al2O3. Using CF4-O2 based plasma, a lapped surface with a surface roughness of over 100 nm can be directly polished to an angstrom level (Sa<0.5 nm), and the atomic surface can be achieved.