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Highlights: [•] Doped HfO2 exhibits ferroelectricity. [•] Ferrolectric HfO2 was integrated in 500 nm and 100 nm FETs. [•] Ferroelectricity induces a VT shift enabling non-volatile data storage. [•] Endurance is 20k cycles and retention can be extrapolated to 10 years. [ABSTRACT FROM AUTHOR]

Abstract: The ferroelectric behaviour of silicon doped hafnium oxide has been investigated using metal–insulator–metal capacitor structures for film thicknesses of 9 and 27nm, annealing temperatures between 450 and 1000°C and silicon contents from 0 to 8.5 cat%. For the 9nm thick films, an improvement of the ferroelectric remanent polarization was revealed for decreasing silicon content and increasing annealing temperature, which corresponds well with the HfO2 structural phases observed by x-ray diffraction. An increase of the film thickness up to 27nm induced an apparent decrease of the remanent polarization and modified the temperature dependence. This change in the ferroelectric properties was shown to be determined by the different crystallization behaviour of the thick films with respect to the thin films. [Copyright &y& Elsevier]