Interfacial ‘dead’ layers between metals and ferroelectric thin films generally induce detrimental effects in nanocapacitors, yet their peculiar properties can prove advantageous in other electronic devices. Here, we show that dead layers with low Li concentration located at the surface of LiNbO₃ ferroelectric materials can function as unipolar selectors. LiNbO₃ mesa cells were etched from a single-crystal LiNbO₃ substrate, and Pt metal contacts were deposited on their sides. Poling induced non-volatile switching of ferroelectric domains in the cell, and volatile switching in the domains in the interfacial (dead) layers, with the domain walls created within the substrate being electrically conductive. These features were also confirmed using single-crystal LiNbO₃ thin films bonded to SiO₂/Si wafers. The fabricated nanoscale mesa-structured memory cell with an embedded interfacial-layer selector shows a high on-to-off ratio (>10⁶) and high switching endurance (~10¹⁰ cycles), showing potential for the fabrication of crossbar arrays of ferroelectric domain wall memories.

金属和铁电薄膜之间的界面“死”层通常会在纳米电容器中引起有害的影响，但是它们的独特性能在其他电子设备中却可以证明是有利的。在这里，我们表明位于LiNbO ₃铁电材料表面的具有低Li浓度的死层可以用作单极选择器。从单晶LiNbO ₃蚀刻LiNbO ₃台面电池衬底，并在其侧面沉积Pt金属触点。极化引起单元中铁电畴的非易失性切换，以及界面（死）层中畴的易失性切换，并且在基板内创建的畴壁是导电的。使用结合到SiO ₂ / Si晶片的单晶LiNbO ₃薄膜也证实了这些特征。带有嵌入式界面层选择器的纳米级台面结构存储单元显示出高的通断比（> 10 ⁶）和高的开关耐力（〜10 10^个循环），显示了制造铁电交叉开关阵列的潜力域墙的回忆。