Phase-change properties of GeSbTe thin films deposited by plasma-enchanced atomic layer depositon

Phase-change access memory (PCM) appears to be the strongest candidate for next-generation high-density nonvolatile memory. The fabrication of ultrahigh-density PCM depends heavily on the thin-film growth technique for the phase-changing chalcogenide material. In this study, Ge(2)Sb(2)Te(5) (GST) and GeSb(8)Te thin films were deposited by plasma-enhanced atomic layer deposition (ALD) method using Ge [(CH(3))(2) N](4), Sb [(CH(3))(2) N](3), Te(C(4)H(9))(2) as precursors and plasma-activated H(2) gas as reducing agent of the metallorganic precursors. Compared with GST-based device, GeSb(8)Te-based device exhibits a faster switching speed and reduced reset voltage, which is attributed to the growth-dominated crystallization mechanism of the Sb-rich GeSb(8)Te films. These results show that ALD is an attractive method for preparation of phase-change materials.