In this paper, we demonstrate an improvement of the On/Off ratio of FTJ devices by the introduction of a high-k Y2O3 layer. To demonstrate the impact of the tunneling barrier layer on the performance of the FTJ, the Al2O3 dielectric layer is investigated for comparison. We report on the increase of the current density with cycling and observe how the on-current is mainly determined by the ferroelectric layer although the dielectric layer is contributing to a boost of the TER by influencing the off state.