Local resistance switching at grain and grain boundary surfaces of polycrystalline tungsten oxide films
Local resistance switching at grain and grain boundary surfaces of polycrystalline tungsten oxide films
复制标题
多晶氧化钨薄膜晶粒和晶界表面的局部电阻变化
DOI：
10.1088/0957-4484/22/25/254008
复制
发表时间：
2011-06-24
期刊：
影响因子：
3.5
通讯作者：
Shen, Bao-Gen
中科院分区：
文献类型：
--
作者：
Shang, Da-Shan;Shi, Lei;Shen, Bao-Gen
利用导电原子力显微镜研究了制备和氧退火的多晶氧化钨薄膜的电阻开关行为。氧退火膜的绝缘性优于制备膜。局部电流分布表明，氧退火膜的晶界电导率比晶界电导率低。可逆的电阻转换行为只发生在氧退火薄膜的晶粒表面，电阻转换过程是由质子的电化学迁移或氧空位引起的钨离子的局部价态变化来描述的。晶粒和晶界表面之间的不同电阻转换行为归因于后退火过程引起的不同氧空位密度。本研究结果对纳米级阻性非易失性存储器件的制造具有重要意义。
Resistance switching behavior has been investigated in as-prepared and oxygen-annealed polycrystalline tungsten oxide films using conductive atomic force microscopy. The oxygen-annealed film appeared more insulative than the as-prepared films. The local current distributions demonstrated the lower conductivity at the grain boundaries than at the grains in the oxygen-annealed films. Reversible resistance switching behavior only occurred at the grain surface region of the oxygen-annealed films and the resistance switching process was described by the local valence change of tungsten ions induced by electrochemical migration of protons or oxygen vacancies. This different resistance switching behavior between the grain and grain boundary surface was attributed to the different oxygen vacancy density caused by the post-annealing process. The present results would be especially meaningful for the fabrication of nanoscale resistive nonvolatile memory devices.