Roles of Inner and Outer Fringe and Asymmetric Coupling Effect in Concentric Double-MIS(p) Tunneling Diodes

Abstract

During the studies of coupling effects between the outer ring and inner circle in a concentric structure of double-metal-insulator-semiconductor tunnel diode, we have proposed an asymmetric coupling effect to account for the distinctive difference between two opposite operations. However, further investigation is needed to make our mechanism more robust. In this work, we designed two sets of ring-shaped and concentric MIS tunnel diode lithographic patterns with a fixed inner fringe in the first set and a fixed outer fringe in the second set. From both the experimental and TCAD-simulated results, we have found that the major role in grabbing charges is the outer fringe of a ring-shaped MIS structure and that this outer fringe-dominated characteristic accompanied with the asymmetric coupling effect results in the observable difference in two contrary operation modes where the inner circle and outer ring take turns to play as the control gate.