School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245, USA.
ACS Nano. 2010 Feb 23;4(2):1234-40. doi: 10.1021/nn901805g.
The localized coupling between piezoelectric and photoexcitation effects of a ZnO micro/nanowire device has been studied for the first time with the goal of designing and controlling the electrical transport characteristics of the device. The piezoelectric effect tends to raise the height of the local Schottky barrier (SB) at the metal-ZnO contact, while photoexcitation using a light that has energy higher than the band gap of ZnO lowers the SB height. By tuning the relative contributions of the effects from piezoelectricity via strain and photoexcitation via light intensity, the local contact can be tuned step-by-step and/or transformed from Schottky to Ohmic or from Ohmic to Schottky. This study describes a new principle for controlling the coupling among mechanical, photonic, and electrical properties of ZnO nanowires, which could be potentially useful for fabricating piezo-phototronic devices.
首次研究了 ZnO 微/纳线器件中压电和光激发效应的局部耦合，目的是设计和控制器件的电输运特性。压电效应倾向于提高金属-ZnO 接触处局部肖特基势垒 (SB) 的高度，而使用能量高于 ZnO 带隙的光进行光激发会降低 SB 高度。通过调节来自应变的压电效应和来自光强度的光激发的相对贡献，可以逐步调整局部接触，或者将其从肖特基转变为欧姆，或者从欧姆转变为肖特基。本研究描述了控制 ZnO 纳米线的机械、光子和电气性能之间耦合的新原理，这对于制造压光电设备可能是有用的。
