Doped hafnium oxide ferroelectric thin films have both excellent size reduction characteristics and good CMOS process compatibility.The ferroelectric capacitor structure is compatible with mainstream DRAM storage architectures,which is a candidate for new memory dielectric materials.As the electrical read and write operations increases,the residual polarization values,representing the"0"and"1"storage states in HfO2 based ferroelectric capacitors,firstly increase and then decrease until the storage window is insufficient or the device fails due to breakdown.It is called the wake up and fatigue effect of the device,leading to reliability issues in storage.In this work,HfO2 based ferroelectric thin films doped with zirconium were prepared into capacitor structures slices with different electrical cycles.The change of residual polarization was related to the microstructure evolution of Hf0.5Zr0 5O2 thin film.The increase of residual polarization during the wake-up process originated from the structural transition from anti ferroelectric tetragonal phase to ferroelectric orthorhombic phase.The structural transformation from ferroelectric orthogonality to paraelectric monoclinic phase was responsible for the residual polarization attenuation during the fatigue process.
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