Patent ID: 8466444

Claim:
A three-terminal switching device for use in integrated circuit devices, comprising: a phase change material (PCM) disposed in contact between a first terminal and a second terminal; a heating device disposed in direct electrical contact between said second terminal and a third terminal, said heating device positioned proximate said PCM, and configured to switch the conductivity of a transformable portion of said PCM between a lower resistance crystalline state and a higher resistance amorphous state; and an insulating layer configured to electrically isolate said heater from said PCM material, and said heater from said first terminal, wherein said PCM, said heater and said insulating layer are formed atop said second terminal; said insulating layer surrounds said PCM and said heater surrounds said insulating layer; said first terminal is formed atop said PCM and adjacent said insulating layer; and said third terminal is formed atop said heater and adjacent said insulating layer.