Ferroelectric Mechanical Memory Based on Remanent Displacement and Method

A nonvolatile memory device comprising:

• two electrically conductive layers adapted to be connected to a voltage source;
• a first layer positioned between the two conductive layers;
• the first layer comprising one of ferroelectric or antiferroelectric material and comprising a fixed portion and a movable portion;
• the movable portion being displaced a predetermined distance from a first position to a second position upon application of one of a positive or negative voltage between the two conductive layers;
• a first contact operatively connectable to at least one of the two conductive layers and to one of a voltage potential or ground;
• the application of one of a positive or negative voltage from the voltage source causing movement of the movable portion from the first to the second position resulting in operative electrical connection between at least one of the two conductive layers and the first contact;
• the movable portion of the first layer being configured to retain a first state if one of a positive or negative voltage is applied and a second state if the opposite of one of a positive or negative voltage is applied;
• wherein the first layer exhibits asymmetrical strain hysteresis and exhibits remanent strain therein such that the reaction of the movable portion of the first layer to the currently applied voltage between the two conductive layers is dependent on the previously applied voltages between the two conductive layers, and wherein the remanent strain is sufficient to retain the movable portion in a first or second position upon removal of the voltage from the two conductive layers.

A method of operating a MEMS switching element for nonvolatile data storage comprising:

• providing two electrically conductive layers adapted to be connected to a voltage source;
• providing a first layer positioned between the two conductive layers;
• the first layer comprising one of ferroelectric or antiferroelectric material and comprising a fixed portion and a movable portion;
• the movable portion being displaced a predetermined distance from a first position to a second position upon application of one of a positive or negative voltage between the two conductive layers;
• providing a first contact operatively connectable to at least one of the two conductive layers and to one of a voltage potential or ground;
• the application of one of a positive or negative voltage from the voltage source causing movement of the movable portion from the first to the second position resulting in operative electrical connection between at least one of the two conductive layers and the first contact;
• the movable portion of the first layer being configured to retain a first state if one of a positive or negative voltage is applied and a second state if the opposite of one of a positive or negative voltage is applied;
• wherein the first layer exhibits asymmetrical strain hysteresis and exhibits remanent strain therein such that the reaction of the movable portion of the first layer to the currently applied voltage between the two conductive layers is dependent on the previously applied voltages between the two conductive layers, and wherein the remanent strain is sufficient to retain the movable portion in a first or second position upon removal of the voltage from the two conductive layers.