標題: A study of electromigration behaviors of Ge2Sb2Te5 chalcogenide nano-strips subjected to pulse bias
作者: Huang, Yin-Hsien
Hsieh, Tsung-Eong
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: chalcogenides;electromigration;pulse bias;average current model;phase-change memory
公開日期: 12-Jul-2017
摘要: Electromigration (EM) behaviors of pristine Ge2Sb2Te5 (GST) and cerium-doped GST (Ce-GST) nano-strips were investigated by the mean-time-to-failure (MTTF) tests under the pulse bias at the conditions of pulse frequency (f) ranging from 1 to 25 MHz and duty cycle ranging from 50% to 80%. Analytical results indicated that, at f greater than 10 MHz, the EM failure of GST nano-strips in pulse bias environment could be depicted by the 'average current model'. With the aid of Black's theory, the activation energies (Ea) of EM process under pulse bias were found to be 0.63 and 0.56 eV for GST and Ce-GST nano-strips, respectively. The Ea values were comparatively smaller than those observed in direct-current MTTF test of GST thin-film samples, implying the enhancement of surface diffusion and skin effect in GST nano-strips. The morphology and composition analyses indicated that the electrostatic and the electron-wind forces might simultaneously involve in the mass transport in GST nano-strips under the test conditions of this study. The composition analysis also revealed that doping could not effectively alleviate the element segregation in GST subjected to electrical bias.
URI: http://dx.doi.org/10.1088/1361-6463/aa749b
http://hdl.handle.net/11536/145690
ISSN: 0022-3727
DOI: 10.1088/1361-6463/aa749b
期刊: JOURNAL OF PHYSICS D-APPLIED PHYSICS
Volume: 50
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