Performance comparison of planar and cylindrical ferroelectric tunnel junctions

A comprehensive comparison of the electrical characteristics between the planar (P-FTJ) and cylindrical ferroelectric tunnel junction (C-FTJ) is conducted based on physical modeling and simulation. The FTJ architecture is consisted of metal-ferroelectric-dielectric-metal stacks. Two configurations of C-FTJ are considered depending on whether the position of ferroelectric layer is close or away from the inner electrode. The differences between the P-FTJ and C-FTJs in the distributions of the electric field and ferroelectric polarization are analyzed. The resultant tunneling electroresistance (TER) are explored as a function of the inner radius, ferroelectric thickness, dielectric thickness, and remnant polarization. These simulation results offer physical insights into achieving highly integrated three-dimensional storage structures through improving the TER ratio.