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• The Sb 54 Zn 46 thin film is fabricated by antimony and zinc targets co-sputtering. • The thermal stability of Sb 54 Zn 46 can satisfy the electro-mobile application. • The strong Sb-Zn bond stretching mode accounts for the high thermal stability. • The phase change speed of Sb 54 Zn 46 (10 ns) is much faster than that of Ge 2 Sb 2 Te 5. • Growth-dominant crystallization mechanism explains the fast phase change speed. In this work, we fabricate the Sb 54 Zn 46 thin film by pure antimony and zinc targets co-sputtering and analyze its phase change properties. The ten-years data retention of Sb 54 Zn 46 thin film, being a good reflection of thermal stability, is improved to 119 °C from 24 °C of pristine antimony thin film, which is much higher than that of the traditional phase change material Ge 2 Sb 2 Te 5 (85 °C). The increased thermal stability of Sb 54 Zn 46 thin film mainly derives from the formation of the strong Sb-Zn bond stretching mode during crystallization. In addition, the phase change speed of Sb 54 Zn 46 thin film measured in device test increases to 10 ns, which is also much faster than that of the traditional phase change material Ge 2 Sb 2 Te 5 (100 ns). These results illustrate that the fast phase change speed of Sb 54 Zn 46 thin film is mainly ascribed to the Sb-rich atomic environment and the growth-dominant crystallization mechanism. Our work substantiates the co-sputtering Sb 54 Zn 46 thin film can ensure fast phase change speed while effectively increasing its thermal stability. [ABSTRACT FROM AUTHOR]

Abstract: A phase change alloy has been synthesized and characterized. The reversible phase transitions between amorphous and crystalline states of SnSe4 films have been studied using variable electrical pulses and X-ray diffraction. Temperature dependent sheet resistance measurements have shown two distinct resistivity states of more than two orders of magnitude. This high electrical contrast makes the alloy suitable for nonvolatile phase change memory applications. X-ray diffraction has attributed the large electrical contrast to an amorphous–crystalline phase transition. The nonvolatile memory cells have been fabricated using a simple sandwich structure (metal/chalcogenide thin film/metal). A threshold voltage of 3.71V has been determined for this phase change random access memory cell. Memory switching was initiated using the voltage pulses of 3.71V, 90ns, 1.3V and 26μs, for the crystallization and amorphization process, respectively. [Copyright &y& Elsevier]

Abstract: Phase change random access memory (PCRAM) requires an advanced phase change material to lower its power consumption and to enhance its data retention and endurance abilities. The present work investigated the crystallization behaviors and electrical properties of Ge1Cu2Te3 compound films with a low melting point of about 500°C for PCRAM application. Sputter-deposited Ge1Cu2Te3 amorphous films showed a high crystallization temperature of about 250°C. The Ge1Cu2Te3 amorphous film showed an electrical resistance decrease of over 102-fold and exhibited a small increase in thickness of 2.0% upon crystallization. The Ge1Cu2Te3 memory devices showed reversible switching behaviors and exhibited a 10% lower power consumption for the reset operation than the conventional Ge2Sb2Te5 memory devices. Therefore, the Ge1Cu2Te3 compound is a promising phase change material for PCRAM application. [Copyright &y& Elsevier]