Department of Mechanical Engineering, Virginia Tech, Goodwin Hall, 635 Prices Fork Road - MC 0238, Blacksburg, Virginia 24061, USA.
J Chem Phys. 2017 Mar 28;146(12):124706. doi: 10.1063/1.4979041.
A number of electronic devices involve metal/oxide interfaces in their structure where the oxide layer plays the role of electrical insulator. As the downscaling of devices continues, the oxide thickness can spread over only a few atomic layers, making the role of interfaces prominent on its insulating properties. The prototypical Al/SiO metal/oxide interface is investigated using first principle calculations, and the effect of the interfacial atomic bonding is evidenced. It is shown that the interface bonding configuration critically dictates the mechanical and electronic properties of the interface. Oxygen atoms are found to better delimit the oxide boundaries than cations. Interfacial cation-metal bonds allow the metal potential to leak inside the oxide layer, without atomic diffusion, leading to a virtual oxide thinning.
许多电子设备的结构中都涉及金属/氧化物界面，其中氧化物层起着电绝缘体的作用。随着器件的不断缩小，氧化物厚度可能只有几个原子层，这使得界面在其绝缘性能上的作用更加突出。本文使用第一性原理计算研究了典型的 Al/SiO 金属/氧化物界面，并证明了界面原子键合的作用。结果表明，界面键合结构对界面的力学和电子性质具有决定性影响。氧原子比阳离子更能更好地限定氧化物的边界。界面阳离子-金属键允许金属电势在没有原子扩散的情况下泄漏到氧化物层内部，导致虚拟的氧化物减薄。
