Ultra-multiple and reproducible resistance levels based on intrinsic crystallization properties of Ge1Sb4Te7 film

- The resistivity of Ge1Sb4Te7 gradually dropped by about 3-4 orders of magnitude due to crystallization with the annealing temperature, which is critical to realize multiple resistance levels.
- The ultra-multiple 27 resistance levels in TiSi3/GST147 lateral phase-change memory device were demonstrated, much more than reported until now.
- The reproducibility of the six resistance levels without programming algorism such as write-certification were demonstrated and these levels were distinguishable from each other.