The Si2Sb2Te5 phase change material has been studied by applying a nano-tip（30 nm in diameter） on an atomic force microscopy system.Memory switching from a high resistance state to a low resistance state has been ac...The Si2Sb2Te5 phase change material has been studied by applying a nano-tip（30 nm in diameter） on an atomic force microscopy system.Memory switching from a high resistance state to a low resistance state has been achieved,with a resistance change of about 1000 times.In a typical I-V curve,the current increases significantly after the voltage exceeds～4.3 V.The phase transformation of a Si2Sb2Te5 film was studied in situ by means of in situ X-ray diffraction and temperature dependent resistance measurements.The thermal stability of Si2Sb2Te5 and Ge2Sb2Te5 was characterized and compared as well.展开更多
Phase change random access memory （PCRAM） is one of the best candidates for next generation non- volatile memory, and phase change SiESbETe5 material is expected to be a promising material for PCRAM. In the fabricat...Phase change random access memory （PCRAM） is one of the best candidates for next generation non- volatile memory, and phase change SiESbETe5 material is expected to be a promising material for PCRAM. In the fabrication of phase change random access memories, the etching process is a critical step. In this paper, the etching characteristics of Si2Sb2Te5 films were studied with a CF4/Ar gas mixture using a reactive ion etching system. We observed a monotonic decrease in etch rate with decreasing CF4 concentration, meanwhile, Ar concentration went up and smoother etched surfaces were obtained. It proves that CF4 determines the etch rate while Ar plays an im- portant role in defining the smoothness of the etched surface and sidewall edge acuity. Compared with GeESbETe5, it is found that Si2Sb2Te5 has a greater etch rate. Etching characteristics of Si2SbETe5 as a function of power and pressure were also studied. The smoothest surfaces and most vertical sidewalls were achieved using a CF4/Ar gas mixture ratio of 10/40, a background pressure of 40 mTorr, and power of 200 W.展开更多
基金supported by the State Key Development Program for Basic Research of China (Nos. 2007CB935400, 2006CB302700)the National High Technology Research and Development Program of China (Nos. 2008AA031402, 2006AA03Z360)+4 种基金the Science and Technology Council of Shanghai (Nos. 0652nm052, 0752nm013, 0752nm014, 07QA14065, 07SA08)the Shanghai Postdoctoral Scientific Foundation (No. 07R214204)the China Postdoctoral Scientific Foundation (No. 20070420105)the National Natural Science Foundation of China (No. 60776058)the Chinese Academy of Sciences (No. 083YQA1001)
文摘The Si2Sb2Te5 phase change material has been studied by applying a nano-tip（30 nm in diameter） on an atomic force microscopy system.Memory switching from a high resistance state to a low resistance state has been achieved,with a resistance change of about 1000 times.In a typical I-V curve,the current increases significantly after the voltage exceeds～4.3 V.The phase transformation of a Si2Sb2Te5 film was studied in situ by means of in situ X-ray diffraction and temperature dependent resistance measurements.The thermal stability of Si2Sb2Te5 and Ge2Sb2Te5 was characterized and compared as well.
基金supported by National Key Basic Research Program of China(Nos.2010CB934300,2011CBA00607,2011CB9328004)the National Integrate Circuit Research Program of China(No.2009ZX02023-003)+2 种基金the National Natural Science Foundation of China(Nos. 60906004,60906003,61006087,61076121,61176122,61106001)the Science and Technology Council of Shanghai(Nos.11DZ2261000, 11QA1407800)the Chinese Academy of Sciences(No.20110490761)
文摘Phase change random access memory （PCRAM） is one of the best candidates for next generation non- volatile memory, and phase change SiESbETe5 material is expected to be a promising material for PCRAM. In the fabrication of phase change random access memories, the etching process is a critical step. In this paper, the etching characteristics of Si2Sb2Te5 films were studied with a CF4/Ar gas mixture using a reactive ion etching system. We observed a monotonic decrease in etch rate with decreasing CF4 concentration, meanwhile, Ar concentration went up and smoother etched surfaces were obtained. It proves that CF4 determines the etch rate while Ar plays an im- portant role in defining the smoothness of the etched surface and sidewall edge acuity. Compared with GeESbETe5, it is found that Si2Sb2Te5 has a greater etch rate. Etching characteristics of Si2SbETe5 as a function of power and pressure were also studied. The smoothest surfaces and most vertical sidewalls were achieved using a CF4/Ar gas mixture ratio of 10/40, a background pressure of 40 mTorr, and power of 200 W.
