Patent ID: 8685783

Claim:
A method comprising: on a first structure having a first dielectric layer, a second dielectric layer, and a third dielectric layer forming a crown through the third dielectric layer and the second dielectric layer; depositing a fourth dielectric layer over the first structure and thereby over the crown; removing a portion of the fourth dielectric layer to form a first spacer having a remaining portion of the fourth dielectric layer; removing the portion of the fourth dielectric layer also removes a portion of the third dielectric layer and forms a second spacer having a remaining portion of the third dielectric layer, thereby forming a second structure; depositing a phase change layer over the second structure; depositing an electrode layer over the phase change layer; and removing portions of the electrode layer and the phase change layer to form a phase change region having a remaining portion of the phase change layer and to form an electrode region having a remaining portion of the electrode layer, by a chemical-mechanical-polishing process.