Strain-Sensitive Current-Voltage Characteristics of ZnSe Nanowire in Metal-Semiconductor-Metal Nanostructure
TAN Yu, WANG Yan-Guo**
Science College, Hunan Agricultural University, Changsha 410128 Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P. O. Box 603, Beijing 100190
Abstract:Experimental investigation of electrical transport properties is carried out by in situ transmission electron microscopy (TEM) to explore the effect of local strain in ZnSe nanowires (NWs) on improvement of electron transport of Au-ZnSe NW-Au (M-S-M) nanostructure. The results show that the threshold voltage due to the Schottky barrier at the metal-semiconductor NW (M-S) nanocontact is found to decrease significantly when the ZnSe NW bends at the Au-ZnSe junction by the movable probe which can apply longitudinal compression, leading to current-voltage (I–V) characteristics of the M-S-M nanostructure being transformed from a nearly symmetrical to an asymmetrical feature. Alternation of the I–V characteristic can be ascribed to significant depression of the Schottky barrier at the M-S nanocontact due to the band gap being narrowed by highly localized strain. As a result, the I–V characteristics of the M-S-M nanostructure are strain-sensitive and can be modified by local strain intentionally produced in the semiconductor NW. The modifiable I–V characteristics of M-S-M nanostructure confirm that the strain can be used for improvement of transport property of the semiconductor NW-based nanoelectronics with the M-S-M nanostructure.