We propose a tunneling heterostructure by replacing one of the metalelectrodes in a metal/ferroelectric/metal ferroelectric tunnel junction with aheavily doped semiconductor. In this metal/ferroelectric/semiconductor tunneldiode, both the height and the width of the tunneling barrier can beelectrically modulated due to the ferroelectric field effect, leading to acolossal tunneling electroresistance. This idea is implemented inPt/BaTiO3/Nb:SrTiO3 heterostructures, in which an ON/OFF conductance ratioabove 10$^4$ can be readily achieved at room temperature. The colossaltunneling electroresistance, reliable switching reproducibility and long dataretention observed in these ferroelectric tunnel diodes suggest their greatpotential in non-destructive readout nonvolatile memories.
展开▼
