PHASE-CHANGE MEMORY UNIT, A METHOD OF FORMING THE SAME, AND A PHASE-CHANGE MEMORY DEVICE INCLUDING THE SAME, INCLUDING A BOTTOM ELECTRODE HAVING AN IMPROVED STRUCTURE

摘要

PURPOSE: A phase-change memory unit, a method of forming the same, and a phase-change memory device including the same are provided to improve electrical characteristic by heating a phase change material layer pattern with small current and reducing a reset current.;CONSTITUTION: A first lower electrode structure(170) is formed on an ohmic layer(140). The first lower electrode structure comprises a first bottom electrode(174) and a second bottom electrode(172). The first bottom electrode comprises a first metal nitride having a first specific resistance. The second bottom electrode comprises a second metal nitride having a second specific resistance lower than the first specific resistance. A phase change material layer pattern(180) is formed on the lower electrode structure. The top electrode(190) is formed on the phase change material layer pattern.;COPYRIGHT KIPO 2010