Modulating the Electrical Transport Characteristics of a Metal-Semiconductor-Metal Structure by Local Strain Gradient

Metal-semiconductor-Metal (M-S-M) structure is widely used in electronic devices, which plays a key role in device performance. Here, we propose a simple and effective way to modulate the contact characteristics of aluminum (AI)-amorphous indium gallium zinc oxide (a-IGZO)-molybdenum (Mo) structure by applying local strain at the interface between Al layer and a-IGZO layer. Four types of I-V curves including forward rectifying, backward rectifying, linear and approximately symmetric are achieved under different pressures. Due to the nanoscale strain gradient induced by inhomogeneous local strain, flexoelectric potential is generated at the interface of the Al and the a-IGZO, which leads to the energy band bending. Therefore, the barrier height modulation can be realized. Meanwhile, the charges induced by flexoelectric effect in the a-IGZO layer can also modulate the barrier height at the a-IGZO/Mo interface. This work shows great potential to enhance the performance of electronic devices and it is promising for novel electromechanical applications.