A phase change memory element including at least one phase change material layer, and a heater conductor, wherein at least a portion of the heater conductor is circumferentially surrounded by the at least one phase change material layer. The phase change memory element is symmetrical. The phase change memory element can include a top electrode circumferentially surrounding and connected to the at least one phase change material layer, and a bottom electrode in contact with the heater conductor. The phase change memory element can include at least one resistive liner in contact with the at least one phase change material layer.

A memory cell with a recessed bottom electrode and methods of forming the memory cell are described. A bottom electrode can be deposited on a layer of a structure. A first insulator and a second insulator can be deposited on top of the bottom electrode. The first insulator and the second insulator can be spaced apart from one another to form an opening on top of the bottom electrode. A recess can be etched in the bottom electrode. The recess can be etched in a portion of the bottom electrode that is underneath the opening. The recess and the opening can form a pore. Phase change material can be deposited in the pore to form a memory cell.

Atomic layer deposition (ALD) processes for forming Group VA element containing thin films, such as Sb, Sb—Te, Ge—Sb and Ge—Sb—Te thin films are provided, along with related compositions and structures. Sb precursors of the formula Sb(SiR.sup.1R.sup.2R.sup.3).sub.3 are preferably used, wherein R.sup.1, R.sup.2, and R.sup.3 are alkyl groups. As, Bi and P precursors are also described. Methods are also provided for synthesizing these Sb precursors. Methods are also provided for using the Sb thin films in phase change memory devices.

A method of forming a disturb-resistant non volatile memory device includes providing a substrate and forming a first dielectric thereon, forming a first strip of material separated from a second strip of material from a first wiring material, and forming a second dielectric thereon to fill a gap between the first and second strips of material. Openings are formed in the second dielectric exposing portions of the first wiring material. Filing the openings by p+ polysilicon contact material, and then an undoped amorphous silicon material, and then a metal material. A second wiring structure is formed thereon to contact the metal material in the openings. Resistive switching cells are formed from the first wiring structure, the second wiring structure, the contact material, the undoped amorphous silicon material, and the metal material.

A bottom electrode, a phase change material layer, the phase change material layer includes a similar lattice constant as a lattice constant of the bottom electrode, and a top electrode vertically aligned. A phase change material layer, a top electrode adjacent to a first vertical side surface of the phase change material layer, and a bottom electrode adjacent to a second vertical side surface of the phase change material layer. Forming a phase change material layer, forming a top electrode adjacent to a first vertical side surface and overlapping a first portion of an upper horizontal surface of the phase change material layer, forming a bottom electrode, adjacent to a second vertical side surface and overlapping a second portion of the upper horizontal surface of the phase change material layer, and forming a dielectric material horizontally isolating the bottom electrode and the top electrode.

A structure including a bottom electrode, a phase change material layer, the phase change material layer includes a similar lattice constant as a lattice constant of the substrate, a top electrode on and vertically aligned with the phase change material layer, a dielectric material horizontally isolating the bottom electrode from the top electrode and the phase change material layer. A structure including a phase change material layer selected from amorphous silicon, amorphous germanium and amorphous silicon germanium, a top electrode on the phase change material layer, a bottom electrode, a dielectric material isolating the bottom electrode from the top electrode and the phase change material layer. Forming a bottom electrode, forming a phase change material layer adjacent to the bottom electrode, forming a top electrode above the phase change material, forming a dielectric material horizontally isolating the bottom electrode from the top electrode and the phase change material layer.

A phase change material memory device is provided. The phase change material memory device includes one or more electrical contacts in a substrate, and a dielectric cover layer on the electrical contacts and substrate. The phase change material memory device further includes a lower conductive shell in a trench above one of the one or more electrical contacts, and an upper conductive shell on the lower conductive shell in the trench. The phase change material memory device further includes a conductive plug filling the upper conductive shell. The phase change material memory device further includes a liner layer on the dielectric cover layer and conductive plug, and a phase change material block on the liner layer on the dielectric cover layer and in the trench.

A stacked phase change memory structure having a cross-point architecture is provided. The stacked phase change memory structure includes at least two phase change material element-containing structures stacked one atop the other. Each phase change material element-containing structure of the plurality of phase change material element-containing structures has a cross-point architecture and includes, from bottom to top, at least one bottom electrode, a phase change material element, and a top electrode.

A crystallization seed layer in a substrate, a phase change material layer, the phase change material layer includes a similar lattice constant as a lattice constant of the crystallization seed layer, a top electrode adjacent to a first vertical side surface and a bottom electrode adjacent to a second vertical side surface of the phase change material layer. A plurality of memory structures configured in a crossbar array, each including a crystallization seed layer, a phase change material layer above, a top electrode adjacent to a first vertical side surface and a bottom electrode adjacent to a second vertical side surface of the phase change material layer. A method including forming a crystallization seed layer, forming a phase change material layer, forming a top electrode and a bottom electrode on the substrate, each adjacent to a vertical side surface of the phase change material layer.

A memory cell comprising a threshold switching material over a first electrode on a substrate. The memory cell includes a second electrode over the threshold switching material and at least one dielectric material between the threshold switching material and at least one of the first electrode and the second electrode. A memory material overlies the second electrode. The dielectric material may directly contact the threshold switching material and each of the first electrode and the second electrode. Memory cells including only one dielectric material between the threshold switching material and an electrode are disclosed. A memory device including the memory cells and methods of forming the memory cells are also described.