Method of improving stability of domain polarization in ferroelectric thin films
AssigneeNanochip, Inc.
InventorQuan A. Tran
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Abstract
A memory device comprises a ferroelectric media comprising at least one ferroelectric film. The ferroelectric film has an as-grown spontaneous polarization of a first direction. A tip is position over the ferroelectric film and a first voltage is applied to the tip larger than a switching voltage of the ferroelectric film. One or both of the tip and the ferroelectric media is moved to form a first domain having a spontaneous polarization of opposite the first direction. The tip is then positioned over the first domain and a second voltage to the tip smaller than the first voltage to form a second domain smaller than the first domain and having a polarization of the first direction, the second domain defining the bit.
Claims6
A memory device comprising:
- a ferroelectric media comprising at least one ferroelectric film;
- wherein the ferroelectric film has an as-grown spontaneous polarization of a first direction;
- a tip adapted to electrically communicate with the ferroelectric film;
- and
- circuitry to write a bit having a spontaneous polarization of the first direction, the circuitry adapted to:
- position the tip;
- apply a first voltage to the tip larger than a switching voltage of the ferroelectric film;
- move one or both of the tip and the ferroelectric media to form a first domain having a spontaneous polarization of opposite the first direction;
- position the tip over the first domain;
- and
- apply a second voltage to the tip smaller than the first voltage to form a second domain smaller than the first domain and having a polarization of the first direction, the second domain defining the bit.
A method of writing a bit in a ferroelectric film having a spontaneous polarization with a same direction as an as-grown spontaneous polarization of the ferroelectric film comprising:
- positioning a tip in electrically communicative proximity with the ferroelectric film;
- applying a first voltage to the tip larger than a switching voltage of the ferroelectric film;
- moving one or both of the tip and the ferroelectric film to form a first domain having a spontaneous polarization of opposite a direction of the as-grown spontaneous polarization;
- positioning the tip over the first domain;
- and
- applying a second voltage to the tip smaller than the first voltage to form a second domain smaller than the first domain and having a spontaneous polarization of the direction of the as-grown spontaneous polarization, the second domain defining the bit.
A memory device comprising:
- a ferroelectric media comprising at least one ferroelectric film;
- wherein the ferroelectric film has an as-grown spontaneous polarization of a first direction;
- an electrode adapted to electrically communicate with the ferroelectric film;
- a tip adapted to electrically communicate with the ferroelectric film;
- and
- circuitry to write a bit having a spontaneous polarization of the first direction, the circuitry adapted to:
- position the electrode;
- apply a first voltage to the electrode larger than a switching voltage of the ferroelectric film to form a first domain having a spontaneous polarization of opposite a direction of the as-grown spontaneous polarization;
- and
- position the tip over a portion of the ferroelectric film within the first domain;
- apply a second voltage to the tip smaller than the first voltage to form a second domain smaller than the first domain and having a polarization of the first direction, the second domain defining the bit.
A method of writing a bit in a ferroelectric film having a spontaneous polarization with a same direction as an as-grown spontaneous polarization of the ferroelectric film comprising:
- positioning an electrode in electrically communicative proximity with the ferroelectric film;
- applying a first voltage to the electrode larger than a switching voltage of the ferroelectric film to form a first domain having a spontaneous polarization of opposite a direction of the as-grown spontaneous polarization;
- positioning a tip in electrically communicative proximity with the ferroelectric film at a portion of the ferroelectric within the first domain;
- and
- applying a second voltage to the tip smaller than the first voltage to form a second domain smaller than the first domain and having a spontaneous polarization of the direction of the as-grown spontaneous polarization, the second domain defining the bit.
Dependencies are inferred from the claim text.