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.