School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, 30332-0245, USA.
Adv Mater. 2011 Jul 19;23(27):3004-13. doi: 10.1002/adma.201100906. Epub 2011 May 11.
Due to polarization of ions in crystals with noncentral symmetry, such as ZnO, GaN, and InN, a piezoelectric potential (piezopotential) is created in the crystal when stress is applied. Electronics fabricated using the inner-crystal piezopotential as a gate voltage to tune or control the charge transport behavior across a metal/semiconductor interface or a p-n junction are called piezotronics. This is different from the basic design of complimentary metal oxide semiconductor (CMOS) field-effect transistors and has applications in force and pressure triggered or controlled electronic devices, sensors, microelectromechanical systems (MEMS), human-computer interfacing, nanorobotics, and touch-pad technologies. Here, the theory of charge transport in piezotronic devices is investigated. In addition to presenting the formal theoretical frame work, analytical solutions are presented for cases including metal-semiconductor contact and p-n junctions under simplified conditions. Numerical calculations are given for predicting the current-voltage characteristics of a general piezotronic transistor: metal-ZnO nanowire-metal device. This study provides important insight into the working principles and characteristics of piezotronic devices, as well as providing guidance for device design.
由于非中心对称晶体（如 ZnO、GaN 和 InN）中离子的极化，当施加应力时，晶体中会产生压电电势（压电势）。利用晶体内部的压电电势作为栅极电压来调节或控制金属/半导体界面或 p-n 结上的电荷输运行为的电子器件称为压电电子学。这与互补金属氧化物半导体 (CMOS) 场效应晶体管的基本设计不同，并且在力和压力触发或控制电子设备、传感器、微机电系统 (MEMS)、人机交互、纳米机器人和触摸板技术中有应用。在这里，研究了压电电子器件中的电荷输运理论。除了提出正式的理论框架外，还针对简化条件下的金属-半导体接触和 p-n 结等情况提出了解析解。给出了数值计算结果，以预测一般压电晶体管（金属-ZnO 纳米线-金属器件）的电流-电压特性。这项研究为压电电子器件的工作原理和特性提供了重要的见解，并为器件设计提供了指导。
