Researches for developing new types of non-volatile memory devices have been widely conducted to replace the current flash memory devices. In an Edge-Metal-Insulator-Metal (EMIM) junction of metal crossbar structure on a ferroelectric layer, its tunnel resistance is found to change drastically depending on the polarization direction of underlying ferroelectric layer, based on theoretical device modeling. The effective tunnel barrier of EMIM junction becomes quite thin when the ferroelectric polarization pointing downward, leading to a huge reduction of tunnel resistance. It is also found that single three-terminal EMIM/Ferroelectric structure can work as an active memory cell with no need of any additional selection devices. With this proposed structure, the fabrication of all-thin-film-based, high-density, high-speed, low-power, and stackable 3D non-volatile memory architecture can be realized.