Ferroelectric capacitor and method for fabricating the same
AssigneeSamsung Electronics Co., Ltd.
InventorDong-jin Jung
Life of this patent
Estimating the term…
Abstract
A ferroelectric capacitor with a multilayer ferroelectric film to prevent degradation of its ferromagnetic characteristics, wherein the ferroelectric film is made of a lower layer of PZT or PLZT formed on a lower electrode and an upper, titanium rich, layer of PZT, PLZT, or PbTiO3, an upper electrode formed on the upper layer of the ferroelectric film and a protective layer formed to cover the ferroelectric capacitor.
Claims13
A method for fabricating a ferroelectric capacitor, comprising:
- forming a first electrode over a substrate;
- forming a first layer comprising a material selected from the group consisting of PZT and PLZT on the first electrode to be a lower portion of a ferroelectric film;
- forming a second layer on the first layer comprising a material selected from the group consisting of titanium rich PZT containing a titanium to zirconium ratio of greater than one, titanium rich PLZT having a titanium to zirconium ratio of greater than one, and PbTiO3 to be an upper portion the ferroelectric film, wherein the upper portion of the ferroelectric film contains a higher titanium concentration than the lower portion of the ferroelectric film;
- and
- forming a second electrode over the ferroelectric film.
A method of forming a ferroelectric film having a perovskite structure, comprising:
- forming a ferroelectric layer having a perovskite structure containing an upper region having a lower titanium concentration than a lower region;
- and
- supplementing the ferroelectric layer to form a ferroelectric film having a substantially uniform titanium concentration throughout its thickness by ion implanting titanium into the ferroelectric layer and annealing the ferroelectric layer to activate the ion implanted titanium.
A method of forming a ferroelectric film having a perovskite structure, comprising:
- forming a ferroelectric layer having a perovskite structure containing an upper region having a lower titanium concentration than a lower region;
- and
- supplementing the ferroelectric layer to form a ferroelectric film having a substantially uniform titanium concentration throughout its thickness;
- determining the difference in titanium concentration between the upper region and the lower region of the ferroelectric layer based on at least one of
- a) the deposition conditions of the ferroelectric layer;
- and
- b) whether platinum would be used in a device including the ferroelectric layer;
- and
- adjusting the step of supplementing based on the step of determining the difference to form a ferroelectric film having a substantially uniform titanium concentration throughout its thickness.
Dependencies are inferred from the claim text.