Improvements of Electrical Characteristics in Poly-Si Nanowires Thin-Film Transistors with External Connection of a BiFeO3 Capacitor.

ABSTRACT

By a sol-gel method, a BiFeO3 (BFO) capacitor is fabricated and connected with the control thin film transistor (TFT). Compared with a control thin-film transistor, the proposed BFO TFT achieves 56% drive current enhancement and 7-28% subthreshold swing (SS) reduction. Moreover, the effect of the proposed BiFeO3 capacitor on IDS-VGS hysteresis in the BFO TFT is 0.1-0.2 V. Because dVint/dVGS > 1 is obtained at a wide range of VGS, it reveals that the incomplete dipole flipping is a major mechanism to obtain improved SS and a small hysteresis effect in the BFO TFT. Experimental results indicate that sol-gel BFO TFT is a potential candidate for digital application.