A new plasma etching technique using microwave discharge is presented. Silicon wafers are etched by the discharge in a (CF4+O2) gas mixture. Fine patterns with dimensions of 1 µm are etched up to 1 µm in depth without undercutting at a pressure of 5×10-4 Torr with an Al mask having 0.08 µm thickness. Etching is thought to be carried out by chemical reactions. With this technique, the etching rate becomes maximum (2.6×10-2 µm/min) when the mixing ratio γ is 20%. Symbol γ is the partial pressure of O2 divided by the total pressure. The etched depth is proportional to the etching time.
This technique is suitable for etching fine patterns of semiconductor devices.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.