公开(公告)号：GB2515101A

公开(公告)日：2014-12-17

申请号：GB201310630

申请日：2013-06-14

Applicant: IBM

Inventor： SANGBUM KIM ,  KREBS DANIEL ,  LAM HON CHUNG ,  POZIDIS CHARALAMPOS

IPC: G11C11/56 ,  G11C13/00 ,  H01L45/00

Abstract: Phase-change memory cells 40 are provided for storing information in a plurality of programmable cell states. A phase-change material 41 is located between first and second electrodes 42,43 for applying a read voltage to the phase-change material to read the programmed cell state. An electrically-conductive component 44 and comprising for example Tantalum Nitride (TaN) or Titanium Aluminium Nitride (TiAlN) extends from one electrode to the other, but also is in contact with the phase-change material 41. The resistance presented by the electrically conductive component 44 to a cell current produced by the read voltage placed across the electrodes 43,46 is less than that of the amorphous phase, and greater than that of the crystalline phase, of the phase-change material 41 in any of said cell states. The electrically conductive material may form a sheath or lining surrounding the phase change material 41 and may comprise of layers of material ranging between 1 and 5nm. The sheath may have a base portion disposed between the phase change material and the electrode and may be in contact with both electrodes. The phase change material in cross section may be smaller or narrower near one of the electrodes. The cell may store more than two levels or information s>2. The memory device may further comprise an array of phase change memory cells and a read write controller for reading and writing data.