| 摘要 |
A manufacturing method of a thin-film element that uses a niobic acid-based ferroelectric material and does not contain lead is provided which, without deterioration of the ferroelectric characteristics, enables efficient and highly accurate fine processing of an upper electrode membrane formed laminated on the surface of a ferroelectric thin film. This manufacturing method of a ferroelectric thin-film element is characterized by involving a lower electrode film forming step for forming a lower electrode film on a substrate, a ferroelectric thin film forming step for forming a niobic acid-based ferroelectric thin film on the aforementioned lower electrode film, an upper electrode film forming step for forming an upper electrode film on the aforementioned niobic acid-based ferroelectric thin film, and an upper electrode film etching step for subjecting the aforementioned upper electrode film to fine processing in a desired pattern by reactive ion etching of said upper electrode film, wherein, in the upper electrode film etching step, the rate of change of the Na emission intensity in the ion plasma generated by the reactive ion etching is calculated, and etching completion is determined at the point in time when said rate of change falls below a prescribed threshold value. |
