A novel slow-down set waveform is proposed to improve the set performance and a 1 kb phase change random access memory chip fabricated with a 13nm CMOS technology is implemented to investigate the set performance by d...A novel slow-down set waveform is proposed to improve the set performance and a 1 kb phase change random access memory chip fabricated with a 13nm CMOS technology is implemented to investigate the set performance by different set programming strategies based on this new set pulse. The amplitude difference （I1 - I2） of the set pulse is proved to be a crucial parameter for set programming. We observe and analyze the cell characteristics with different I1 - I2 by means of thermal simulations and high-resolution transmission electron microscopy, which reveal that an incomplete set programming will occur when the proposed slow-down pulse is set with an improperly high I1 - I2. This will lead to an amorphous residue in the active region. We also discuss the programming method to avoid the set performance degradations.展开更多
In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad. School of Medicine, Tsinghua...In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad. School of Medicine, Tsinghua University展开更多
In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad.
According to the giant impact hypothesis,the Moon was formed by the collision of a Mars-sized celestial body with proto-Earth,and the origin of the Moon is directly related to the initial evolution of Earth.The Moon h...According to the giant impact hypothesis,the Moon was formed by the collision of a Mars-sized celestial body with proto-Earth,and the origin of the Moon is directly related to the initial evolution of Earth.The Moon has no atmosphere,and its significant geological tectonic activity ceased in the very early stage;hence,it preserves the most complete evolution records of the habitable environment in the inner solar system,which was mainly controlled by asteroid impact and solar radiation.With development of space technology,the Moon has been taken as a target for future exploration and research[1–3].In 2004,China launched the Chang’e lunar exploration program.Since then,we have successfully achieved orbiting,landing,and returning,which are the key technologies for lunar exploration.The program has also returned the youngest lunar samples and conducted the first soft landing and in situ exploration on the far side of the Moon[4].Meanwhile,the Chinese government has announced its plan to send humans to the Moon by 2030 and has initiated a feasibility study for the international lunar research station program[5].With this context,we had the idea to organize a special issue of“Key Scientific Questions for Future Lunar Exploration”,which focuses on the thinking of Chinese scientists on key scientific issues,especially those related to manned lunar exploration in recent coming years,so as to provide inputs for condensing the scientific objectives of future lunar exploration missions.Space:Science&Technology was chosen because of its important influence in the fields of scientific research and engineering of lunar and planetary exploration.展开更多
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences under Grant No XDA09020402the National Key Basic Research Program of China under Grant Nos 2013CBA01900,2010CB934300,2011CBA00607,and 2011CB932804+2 种基金the National Integrate Circuit Research Program of China under Grant No 2009ZX02023-003the National Natural Science Foundation of China under Grant Nos 61176122,61106001,61261160500,and 61376006the Science and Technology Council of Shanghai under Grant Nos 12nm0503701,13DZ2295700,12QA1403900,and 13ZR1447200
文摘A novel slow-down set waveform is proposed to improve the set performance and a 1 kb phase change random access memory chip fabricated with a 13nm CMOS technology is implemented to investigate the set performance by different set programming strategies based on this new set pulse. The amplitude difference （I1 - I2） of the set pulse is proved to be a crucial parameter for set programming. We observe and analyze the cell characteristics with different I1 - I2 by means of thermal simulations and high-resolution transmission electron microscopy, which reveal that an incomplete set programming will occur when the proposed slow-down pulse is set with an improperly high I1 - I2. This will lead to an amorphous residue in the active region. We also discuss the programming method to avoid the set performance degradations.
文摘In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad. School of Medicine, Tsinghua University
文摘In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad.
文摘According to the giant impact hypothesis,the Moon was formed by the collision of a Mars-sized celestial body with proto-Earth,and the origin of the Moon is directly related to the initial evolution of Earth.The Moon has no atmosphere,and its significant geological tectonic activity ceased in the very early stage;hence,it preserves the most complete evolution records of the habitable environment in the inner solar system,which was mainly controlled by asteroid impact and solar radiation.With development of space technology,the Moon has been taken as a target for future exploration and research[1–3].In 2004,China launched the Chang’e lunar exploration program.Since then,we have successfully achieved orbiting,landing,and returning,which are the key technologies for lunar exploration.The program has also returned the youngest lunar samples and conducted the first soft landing and in situ exploration on the far side of the Moon[4].Meanwhile,the Chinese government has announced its plan to send humans to the Moon by 2030 and has initiated a feasibility study for the international lunar research station program[5].With this context,we had the idea to organize a special issue of“Key Scientific Questions for Future Lunar Exploration”,which focuses on the thinking of Chinese scientists on key scientific issues,especially those related to manned lunar exploration in recent coming years,so as to provide inputs for condensing the scientific objectives of future lunar exploration missions.Space:Science&Technology was chosen because of its important influence in the fields of scientific research and engineering of lunar and planetary exploration.
