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Scandium doping brings speed improvement in Sb2Te alloy for phase change random access memory application.

ABSTRACT: Phase change random access memory (PCRAM) has gained much attention as a candidate for nonvolatile memory application. To develop PCRAM materials with better properties, especially to draw closer to dynamic random access memory (DRAM), the key challenge is to research new high-speed phase change materials. Here, Scandium (Sc) has been found it is helpful to get high-speed and good stability after doping in Sb2Te alloy. Sc0.1Sb2Te based PCRAM cell can achieve reversible switching by applying even 6?ns voltage pulse experimentally. And, Sc doping not only promotes amorphous stability but also improves the endurance ability comparing with pure Sb2Te alloy. Moreover, according to DFT calculations, strong Sc-Te bonds lead to the rigidity of Sc centered octahedrons, which may act as crystallization precursors in recrystallization process to boost the set speed.

SUBMITTER: Chen X

PROVIDER: S-EPMC5931567 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Scandium doping brings speed improvement in Sb2Te alloy for phase change random access memory application.

Chen Xin X Zheng Yonghui Y Zhu Min M Ren Kun K Wang Yong Y Li Tao T Liu Guangyu G Guo Tianqi T Wu Lei L Liu Xianqiang X Cheng Yan Y Song Zhitang Z

Scientific reports 20180501 1

Phase change random access memory (PCRAM) has gained much attention as a candidate for nonvolatile memory application. To develop PCRAM materials with better properties, especially to draw closer to dynamic random access memory (DRAM), the key challenge is to research new high-speed phase change materials. Here, Scandium (Sc) has been found it is helpful to get high-speed and good stability after doping in Sb2Te alloy. Sc0.1Sb2Te based PCRAM cell can achieve reve ...[more]

PMID: 29717216

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