Abstract: A ferroelectric tunnel junction is formed, comprising a plurality of layers including at least a bottom electrode layer, a top electrode layer, and at least one ferroelectric layer disposed between the bottom electrode layer and the top electrode layer. The at least one ferroelectric layer comprises a ferroelectric material. At least one layer of the plurality of layers is in contact with the ferroelectric layer and has a coefficient of thermal expansion that is at least 25% lower than a coefficient of thermal expansion of the ferroelectric layer; and inducing ferroelectric phase crystallization in the ferroelectric layer by annealing the plurality of layers.

Abstract: Methods for programming memory cells of a resistive memory device include applying a voltage pulse sequence to a memory cell to set a logic state of the memory cell. An initial set sequence of voltage pulses may be applied to the memory cell, followed by a reform voltage pulse having an amplitude greater than the amplitudes of the initial set sequence, and within ±5% of the amplitude of a voltage pulse used in an initial forming process. Additional voltage pulses having amplitudes that are less than the amplitude of the reform voltage pulse may be subsequently applied. By applying a reform voltage pulse in the middle of, or at the end of, a memory set sequence including multiple voltage pulses, a resistive memory device may have a larger memory window and improved data retention relative to resistive memory devices programmed using conventional programming methods.

Abstract: Various embodiments of the present disclosure are directed towards a memory cell comprising a blocking layer configured to block diffusion of metal from an electrode of the memory cell to a ferroelectric layer of the memory cell. More particularly, the blocking layer and the ferroelectric layer are between a top electrode of the memory cell and a bottom electrode of the memory cell, which both comprise metal. Further, the blocking layer is between the ferroelectric layer and the electrode, which corresponds to one of the top and bottom electrodes. In some embodiments, the metal of the one of the top and bottom electrodes has a lowest electronegativity amongst the metals of top and bottom electrodes and is hence the most reactive and likely to diffuse amongst the metals of top and bottom electrodes.

Abstract: Methods for programming memory cells of a resistive memory device include applying a voltage pulse sequence to a memory cell to set a logic state of the memory cell. An initial set sequence of voltage pulses may be applied to the memory cell, followed by a reform voltage pulse having an amplitude greater than the amplitudes of the initial set sequence, and within ±5% of the amplitude of a voltage pulse used in an initial forming process. Additional voltage pulses having amplitudes that are less than the amplitude of the reform voltage pulse may be subsequently applied. By applying a reform voltage pulse in the middle of, or at the end of, a memory set sequence including multiple voltage pulses, a resistive memory device may have a larger memory window and improved data retention relative to resistive memory devices programmed using conventional programming methods.

Abstract: Various embodiments of the present application are directed towards a resistive random-access memory (RRAM) cell comprising a barrier layer to constrain the movement of metal cations during operation of the RRAM cell. In some embodiments, the RRAM cell further comprises a bottom electrode, a top electrode, a switching layer, and an active metal layer. The switching layer, the barrier layer, and the active metal layer are stacked between the bottom and top electrodes, and the barrier layer is between the switching and active metal layers. The barrier layer is conductive and between has a lattice constant less than that of the active metal layer.

Abstract: Methods for programming memory cells of a resistive memory device include applying a voltage pulse sequence to a memory cell to set a logic state of the memory cell. An initial set sequence of voltage pulses may be applied to the memory cell, followed by a reform voltage pulse having an amplitude greater than the amplitudes of the initial set sequence, and within ±5% of the amplitude of a voltage pulse used in an initial forming process. Additional voltage pulses having amplitudes that are less than the amplitude of the reform voltage pulse may be subsequently applied. By applying a reform voltage pulse in the middle of, or at the end of, a memory set sequence including multiple voltage pulses, a resistive memory device may have a larger memory window and improved data retention relative to resistive memory devices programmed using conventional programming methods.

Abstract: Various embodiments of the present application are directed towards a resistive random-access memory (RRAM) cell comprising a barrier layer to constrain the movement of metal cations during operation of the RRAM cell. In some embodiments, the RRAM cell further comprises a bottom electrode, a top electrode, a switching layer, and an active metal layer. The switching layer, the barrier layer, and the active metal layer are stacked between the bottom and top electrodes, and the barrier layer is between the switching and active metal layers. The barrier layer is conductive and between has a lattice constant less than that of the active metal layer.

Abstract: Methods for programming memory cells of a resistive memory device include applying a voltage pulse sequence to a memory cell to set a logic state of the memory cell. An initial set sequence of voltage pulses may be applied to the memory cell, followed by a reform voltage pulse having an amplitude greater than the amplitudes of the initial set sequence, and within ±5% of the amplitude of a voltage pulse used in an initial forming process. Additional voltage pulses having amplitudes that are less than the amplitude of the reform voltage pulse may be subsequently applied. By applying a reform voltage pulse in the middle of, or at the end of, a memory set sequence including multiple voltage pulses, a resistive memory device may have a larger memory window and improved data retention relative to resistive memory devices programmed using conventional programming methods.

Abstract: Various embodiments of the present application are directed towards a resistive random-access memory (RRAM) cell comprising a barrier layer to constrain the movement of metal cations during operation of the RRAM cell. In some embodiments, the RRAM cell further comprises a bottom electrode, a top electrode, a switching layer, and an active metal layer. The switching layer, the barrier layer, and the active metal layer are stacked between the bottom and top electrodes, and the barrier layer is between the switching and active metal layers. The barrier layer is conductive and between has a lattice constant less than that of the active metal layer.

Abstract: A method of forming a memory device includes: forming a polish stop layer over a metallization layer in an inter-metal dielectric layer; performing an etching process to form an opening in the polish stop layer, in which a sidewall of the opening extends at an acute angle relative to a top surface of the polish stop layer; forming an electrode material in the opening and over the polish stop layer; planarizing the electrode material until a top surface of the polish stop layer is exposed so as to form a bottom electrode surrounded by the polish stop layer; and forming a stack of a resistance switching layer and a top electrode over the bottom electrode.

Abstract: A memory device includes a metal structure, a first dielectric layer, a bottom electrode, a second dielectric layer, a resistance switching layer, and a top electrode. The first dielectric layer surrounds the metal structure. The bottom electrode is in contact with a top surface of the metal structure. The second dielectric layer surrounds the bottom electrode, in which a top surface of the bottom electrode is higher than a top surface of the second dielectric layer. The resistance switching layer is over the bottom electrode. The top electrode is over the resistance switching layer.

Abstract: Various embodiments of the present application are directed towards a resistive random-access memory (RRAM) cell comprising a barrier layer to constrain the movement of metal cations during operation of the RRAM cell. In some embodiments, the RRAM cell further comprises a bottom electrode, a top electrode, a switching layer, and an active metal layer. The switching layer, the barrier layer, and the active metal layer are stacked between the bottom and top electrodes, and the barrier layer is between the switching and active metal layers. The barrier layer is conductive and has a lattice constant less than that of the active metal layer.

Abstract: Various embodiments of the present application are directed towards a resistive random-access memory (RRAM) cell comprising a barrier layer to constrain the movement of metal cations during operation of the RRAM cell. In some embodiments, the RRAM cell further comprises a bottom electrode, a top electrode, a switching layer, and an active metal layer. The switching layer, the barrier layer, and the active metal layer are stacked between the bottom and top electrodes, and the barrier layer is between the switching and active metal layers. The barrier layer is conductive and between has a lattice constant less than that of the active metal layer.

Abstract: A memory device includes a metal structure, a first dielectric layer, a bottom electrode, a second dielectric layer, a resistance switching layer, and a top electrode. The first dielectric layer surrounds the metal structure. The bottom electrode is in contact with a top surface of the metal structure. The second dielectric layer surrounds the bottom electrode, in which a top surface of the bottom electrode is higher than a top surface of the second dielectric layer. The resistance switching layer is over the bottom electrode. The top electrode is over the resistance switching layer.

Abstract: A method of forming a memory device includes: forming a polish stop layer over a metallization layer in an inter-metal dielectric layer; performing an etching process to form an opening in the polish stop layer, in which a sidewall of the opening extends at an acute angle relative to a top surface of the polish stop layer; forming an electrode material in the opening and over the polish stop layer; planarizing the electrode material until a top surface of the polish stop layer is exposed so as to form a bottom electrode surrounded by the polish stop layer; and forming a stack of a resistance switching layer and a top electrode over the bottom electrode.

Abstract: A memory device includes a bottom electrode, a resistance switching layer and a top electrode. The bottom electrode is over a metallization layer embedded in an inter-metal dielectric layer. The bottom electrode has a top surface and a sidewall that extends at an obtuse angle relative to the top surface. The resistance switching layer is over the bottom electrode. The top electrode is over the resistance switching layer.

Abstract: A memory device includes a bottom electrode, a resistance switching layer and a top electrode. The bottom electrode is over a metallization layer embedded in an inter-metal dielectric layer. The bottom electrode has a top surface and a sidewall that extends at an obtuse angle relative to the top surface. The resistance switching layer is over the bottom electrode. The top electrode is over the resistance switching layer.

Abstract: A conductive-bridging random access memory and a method for fabricating a conductive-bridging random access memory are provided. The conductive-bridging random access memory includes a bottom electrode layer on a semiconductor substrate, an electrical resistance switching layer on the bottom electrode layer, an electron-capturing layer on the electrical resistance switching layer, a barrier layer on the electron-capturing layer, an ion source layer on the barrier layer, and a top electrode layer on the ion source layer. The electron-capturing layer includes electron-capturing material, and the electron affinity of the electron-capturing material is at least 60 KJ/mole.

Abstract: A conductive-bridging random access memory and a method for fabricating a conductive-bridging random access memory are provided. The conductive-bridging random access memory includes a bottom electrode layer on a semiconductor substrate, an electrical resistance switching layer on the bottom electrode layer, an electron-capturing layer on the electrical resistance switching layer, a barrier layer on the electron-capturing layer, an ion source layer on the barrier layer, and a top electrode layer on the ion source layer. The electron-capturing layer includes electron-capturing material, and the electron affinity of the electron-capturing material is at least 60 KJ/mole.