Phase changeable memory devices

A phase-changeable memory device, comprising:

• a phase-changeable material pattern of a phase-changeable material that includes nitrogen atoms;
• and
• first and second electrodes electrically connected to the phase-changeable material pattern and provide an electrical signal thereto;
• wherein the phase-changeable material pattern has a polycrystalline structure.

A phase-changeable memory device, comprising:

• a phase-changeable material pattern of a phase-changeable material that includes nitrogen atoms;
• and
• first and second electrodes electrically connected to the phase-changeable material pattern and provide an electrical signal thereto;
• wherein the phase-changeable material pattern comprises Ge—Sb—Te—N, As—Sb—Te—N, As—Ge—Sb—Te—N, Sn—Sb—Te—N, In—Sn—Sb—Te—N, Ag—In—Sb—Te—N, 5A group element-Sb—Te—N, 6A group element-Sb—Te—N, 5A group element-Sb—Se—N, and/or 6A group element-Sb—Se—N.

A phase-changeable memory device, comprising:

• a phase-changeable material pattern of a phase-changeable material having a polycrystalline structure;
• and
• first and second electrodes electrically connected to the phase-changeable material pattern to provide an electrical signal thereto;
• wherein an amount of nitrogen atoms in the phase-changeable material pattern is from about 0.25% to about 25% with respect to the total atomic weight of ingredients of the phase-changeable material.

A phase-changeable memory device, comprising:

• a phase-changeable material pattern of a phase-changeable material having a polycrystalline structure;
• and
• first and second electrodes electrically connected to the phase-changeable material pattern to provide an electrical signal thereto;
• wherein the phase-changeable material pattern comprises Ge—Sb—Te—N, As—Sb—Te—N, As—Ge—Sb—Te—N, Sn—Sb—Te—N, In—Sn—Sb—Te—N, Ag—In—Sb—Te—N, a 5A group element-Sb—Te—N, a 6A group element-Sb—Te—N, a 5A group element-Sb—Se—N, and/or a 6A group element-Sb—Se—N.

A phase-changeable memory device, comprising:

• a transistor including a source region, a drain region and a gate electrode disposed on the semiconductor substrate;
• a lower interconnection electrically connected to the drain region;
• a contact pad formed of the same material and placed on the same height as the lower interconnection;
• a variable resistor electrically connected to the contact pad;
• and
• an upper interconnection electrically connected to the variable resistor,
• wherein the variable resistor is interposed between the two electrodes and includes nitrogen atoms.

A phase-changeable memory device comprising:

• a transistor including a source region, a drain region and a gate electrode that are disposed on the semiconductor substrate;
• an interlayer dielectric layer formed on the semiconductor substrate to cover the transistor;
• a lower interconnection disposed in the interlayer dielectric layer to connect to the drain region electrically;
• a contact pad disposed in the interlayer dielectric layer at substantially the same height and formed of the same material as the lower interconnection;
• a lower intermetal dielectric layer disposed on the interlayer dielectric layer;
• a variable resistor electrically connected to the contact pad;
• an upper intermetal dielectric layer disposed on the lower intermetal dielectric layer to cover a side of the variable resistor;
• and
• an upper interconnection disposed in the upper intermetal dielectric layer to connect to the variable resistor electrically,
• wherein the variable resistor comprises:
• a bottom electrode penetrating a portion of the lower intermetal dielectric layer to electrically connect to the contact pad;
• a phase-changeable material pattern containing nitrogen atoms disposed on the lower intermetal dielectric layer and on the bottom electrode;
• and
• a top electrode disposed on the phase-changeable material pattern to electrically connect to the upper interconnection.