PLASMA ETCHING METHOD

PROBLEM TO BE SOLVED: To provide an plasma etching method by which, when a substrate having a structure in which a ferroelectric film made of an oxide is sandwiched between an upper electrode film and a lower electrode film is subjected to plasma etching, the lower electrode which is exposed as the ferroelectric film is etched more, is prevented from being etched. SOLUTION: The plasma etching method carries out in order: a mask forming step of forming the upper electrode film 54 in a mask pattern of a predetermined shape; and a ferroelectric film-etching step of plasma-etching the ferroelectric film 53 until the lower electrode film 52 is exposed, using a fluorocarbon gas as an etching gas and the upper electrode film 54 itself as a mask. In the ferroelectric film etching step, the ferroelectric film 53 is etched while preventing deposition of a polymer onto a bottom surface of an etching processing part, the polymer being produced when the fluorocarbon gas is brought into a plasma state due to oxygen atoms generated due to the etching of the ferroelectric film 53. COPYRIGHT: (C)2011,JPO&INPIT