Structural and electrical analysis of in-sb-te-based PCM cells

Two In–Sb–Te compounds with low Te content (12 at.% and 17 at.%), deposited by metalorganic chemical vapour deposition, were implemented into prototype phase-change memory devices of size 50 × 50 nm2 and 93 × 93 nm2. These chalcogenides yielded devices with higher threshold voltage than those based on Ge–Sb–Te alloys. The endurance and programming window were markedly improved (from 103 to 106 cycles and from 1 to 2 orders of magnitude, respectively) when employing the Te-richer alloy. Moreover, in situ structural and electrical analysis on TiN/In–Sb–Te/dielectric stacks provided additional insight on the thermal stability of the two ternary phases In3SbTe2 and InSb0.8Te0.2, which were found to coexist in these compounds.