With the ability to engineer ferroelectricity in HfO2 thin films, manufacturable and highly scaled MFM capacitors and MFIS-FETs can be implemented into a CMOS-environment. NVM properties of the resulting devices are discussed and contrasted to existing perovskite based FRAM

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The pyroelectric response of polycrystalline, Si-doped HfO2 layers in a thickness range of 10 nm to 50 nm is investigated employing the temperature oscillation method. The largest value of the pyroelectric coefficient is obtained for the 20 nm layer with p = 84 μC m−2 K−1, which is similar to that of lithium niobate. Furthermore, the pyroelectric coefficient is analyzed with respect to field cycling and is found to increase proportionally with the remanent polarization during wake-up, providing further evidence that the hysteresis of the material is truly ferroelectric. However, for different material thicknesses, the switchable polarization and pyroelectric coefficient are not proportional, indicating that only part of the domains is pyroelectrically active, which suggests potential for further improvement of the pyroelectric response. Due to its CMOS compatibility and conformal deposition using atomic layer deposition (ALD), Si-doped HfO2 is a promising candidate for future energy harvesting and sensor applications.

High-k dielectric layers (HfSixOy and ZrO2) with different film morphologies were investigated by tunneling atomic-force microscopy (TUNA). Different current distributions were observed for amorphous and nanocrystalline films by analyzing TUNA current maps. This even holds for crystalline layers where highly resolved atomic-force microscopy cannot detect any crystalline structures. However, TUNA enables the determination of morphology in terms of differences in current densities between nanocrystalline grains and their boundaries. The film morphologies were proven by high-resolution transmission electron microscopy. The investigations show TUNA as powerful current mapping tool for the characterization of morphology in thin high-k films on a nanoscale

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