Patent ID: 7989795

Claim:
A phase change memory device, comprising: a substrate; an electrode layer formed on the substrate; a phase change memory structure formed on the electrode layer and electrically connected to the electrode layer, wherein the phase change memory structure comprises: a cup-shaped heating electrode placed on the electrode layer; an insulating layer placed on the cup-shaped heating electrode along a first direction covering a portion of the cup-shaped heating electrode; an electrode structure placed on the cup-shaped heating electrode along a second direction covering a portion of the insulating layer and the cup-shaped heating electrode; a pair of double spacers placed on a pair of opposite sidewalls of the electrode structure so as to be physically separated from each other by the electrode structure, wherein one of the pair of double spacers covers a portion of the cup-shaped heating electrode and another one of the pair of double spacers is free from contacting the cup-shaped heating electrode, wherein the double spacer comprises a phase change material spacer and an insulating material spacer placed on a sidewall of the phase change material spacer, arranged such that an intersecting area of the phase change material spacer of one of the pair of double spacers and a conductive layer of the cup-shaped heating electrode controls a contact area between the phase change material spacer and the cup-shaped heating electrode.