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Magnetoelectric (ME) composite thin films are promising candidates for novel applications in future nanoelectronics, spintronics, memory and other multifunctional devices as they exhibit much higher ME coupling and transition temperatures (Tc) than well-known single phase multiferroics discovered to date. Among the three types of multiferroic composite nanostructures, (2-2) layered and (1-3) vertically aligned composite nanostructures exhibit comparatively smaller ME coupling due to different shortcomings which restrict their use in many applications. Here we study the morphological, piezoresponse force microscopic (PFM), ferroelectric, magnetic, and magnetodielectric properties of 0-3 (magnetic nanoparticles (0) homogeneously distributed in ferroelectric matrices (3)) multiferroic composite thin films.more » The Pb(Fe_0.5Nb_0.5)O₃ (PFN) - Ni_0.65Zn_0.35Fe₂O₄ (NZFO) particulate composite films were synthesized by pulsed laser deposition (PLD). These particulate composite thin films are completely c-axis oriented with very low surface roughness. We observed magnetic and ferroelectric T_c above room temperature (RT) for all composite thin films. The PFN-NZFO 0-3 composites exhibit large polarization, high saturated magnetization with low coercive field, low dielectric loss along with magnetodielectric coupling at RT. These nanocomposites might be utilized in next generation nano/microelectronics and spintronic devices.« less

We present that metal-insulator-metal (MIM) capacitors comprised of amorphous Si:SrTiO₃-Al₂O₃-Si:SrTiO₃ multi-dielectric architecture have been fabricated employing a combination of pulsed laser and atomic layer deposition techniques. The voltage linearity, temperature coefficients of capacitance, dielectric and electrical properties upon thickness were studied under a wide range of temperature (200–400 K) and electric field stress (61.5 MV/cm). A high capacitance density of 31 fF/μm², a low voltage coefficient of capacitance of 363 ppm/V², a low temperature coefficient of capacitance of <644 ppm/K, and an effective dielectric constant of 133 are demonstrated in a MIM capacitor with 1.4 nm capacitance equivalent thickness inmore » a 40 nm thick ultra high-k multi-dielectric stack. Finally, all of these properties make this dielectric architecture of interest for next generation, highly scaled MIM capacitor applications.« less