A phase-change memory may have a tapered lower electrode coated with an insulator. The coated, tapered electrode acts as a mask for a self-aligned trench etch to electrically separate adjacent wordlines. In some embodiments, the tapered lower electrode may be formed over a plurality of doped regions,...http://www.google.com/patents/US6933516?utm_source=gb-gplus-sharePatent US6933516 - Forming tapered lower electrode phase-change memories
