Cheng Baochang, Ouyang Zhiyong, Chen Chuan, Xiao Yanhe, Lei Shuijin
1] School of Materials Science and Engineering, Nanchang University, Jiangxi 330031, P. R. China [2] Nanoscale Science and Technology Laboratory, Institute for Advanced Study, Nanchang University, Jiangxi 330031, P. R. China.
Sci Rep. 2013 Nov 19;3:3249. doi: 10.1038/srep03249.
Resistive switching (RS) devices are widely believed as a promising candidate for next generation nonvolatile resistance random access memory. Here, Zn2SnO4-sheathed ZnO core/shell heterostructure nanowires were constructed through a polymeric sol-gel approach followed by post-annealing. The back-to-back bipolar RS properties were observed in the Ohmic contact two-terminal devices based on individual core/shell nanowires. With increasing bias to about 1.5 V, it changes from high-resistance states (HRS) to low-resistance states, and however, it can be restored to HRS by reverse bias. We propose a new mechanism, which is attributed to the injection of electrons into/from interfacial states, arising from the lattice mismatch at ZnO/Zn2SnO4 heterointerface. Upon applying negative/positive voltage at one end of devices, where interfacial states are filled/emptied, barrier will be eliminated/created, resulting into symmetric RS characteristics. The behavior of storage and removal charges demonstrates that the heterostructures have excellent properties for the application in resistance random access memory.
电阻开关（RS）器件被广泛认为是下一代非易失性电阻随机存取存储器的一个有前途的候选者。在此，通过聚合物溶胶 - 凝胶法随后进行后退火构建了Zn2SnO4包覆的ZnO核/壳异质结构纳米线。在基于单个核/壳纳米线的欧姆接触两终端器件中观察到了背靠背双极电阻开关特性。随着偏压增加到约1.5 V，它从高电阻状态（HRS）转变为低电阻状态，然而，通过反向偏压它可以恢复到HRS。我们提出了一种新机制，这归因于电子注入到界面态/从界面态注入电子，这是由ZnO/Zn2SnO4异质界面处的晶格失配引起的。在器件一端施加负/正电压时，界面态被填充/排空，势垒将被消除/创建，从而产生对称的电阻开关特性。存储和去除电荷的行为表明，该异质结构在电阻随机存取存储器应用中具有优异的性能。
