Low-Energy Amorphization of Ti₁Sb₂ Te₅ Phase Change Alloy Induced by TiTe₂Nano-Lamellae

Increasing SET operation speed and reducing RESET operation energy have always been the innovation direction of phase change memory (PCM) technology. Here, we demonstrate that ∼87% and ∼42% reductions of RESET operation energy can be achieved on PCM cell based on stoichiometric Ti₁Sb₂Te₅ alloy, compared with Ge2Sb₂Te₅ and non-stoichiometric Ti0.4Sb₂Te3 based PCM cells at the same size, respectively. The Ti₁Sb₂Te₅ based PCM cell also shows one order of magnitude faster SET operation speed compared to that of the Ge2Sb₂Te₅ based one. The enhancements may be caused by substantially increased concentration of TiTe₂ nano-lamellae in crystalline Ti₁Sb₂Te₅ phase. The highly electrical conduction and lowly thermal dissipation of the TiTe₂ nano-lamellae play a major role in enhancing the thermal efficiency of the amorphization, prompting the low-energy RESET operation. Our work may inspire the interests to more thorough understanding and tailoring of the nature of the (TiTe₂)n(Sb₂Te3)m pseudobinary system which will be advantageous to realize high-speed and low-energy PCM applications.