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Gd and Si co-doped HfO2 gate dielectric thin films were prepared by atomic layer deposition (ALD), while Gd[N(SiMe3)2]3, Hf[NEtMe]4, and H2O are chosen to be precursors. The Gd and Si were successfully co-doped into HfO2 films using only one doping precursor Gd[N(SiMe3)2]3. The doping concentration can be facilely tuned by controlling ALD recipe. The atomic percentages of Si/(Si + Gd + Hf) and Gd/(Si + Gd + Hf) increase from 11.5 to 28.9% and from 6.8 to 28.4% when changing the ALD cycle ratio of GdxSiyO to HfO2 from 1:9 to 1:1. The band gap and band alignment were investigated by X-ray photoelectron spectroscopy. The results imply that the band gap of Gd/Si co-doped HfO2 films has a positive relation with doping concentration. Moreover, the valence band offset decreases with doping concentration first but then increases, while the change of conduction band offset is opposite. The (1:6)-HfxGdySizO films with 11.6 at.% Gd/(Gd + Hf) exhibit the maximum accumulation capacitance and dielectric constant, which are only slightly smaller than those of the HfO2 films. Compared to HfO2 films, the leakage current density of (1:6)-HfxGdySizO films is decreased by at least one order of magnitude. Therefore, Gd and Si co-doping can improve the electrical properties of HfO2 films. [ABSTRACT FROM AUTHOR]

Highlights: [•] Memory cells containing chemically-synthesized FePt nanocrystals are fabricated. [•] A hexagonal arrangement monolayer is self-assembled on alumina by dip-coating. [•] The core–shell structure is formed with alloy core and amorphous iron oxide shell. [•] The MOS capacitors are electrically measured exhibiting obvious memory effects. [ABSTRACT FROM AUTHOR]

Highlights: [•] Atomic layer deposition growth of Pt nanocrystals on Al2O3 film is investigated. [•] Pure metallic Pt nanocrystals can be formed at the initial growth stage. [•] Large area high density Pt nanocrystals are utilized for nonvolatile memory. [•] The MOS capacitors exhibit obvious memory effects including good retention. [•] Fowler–Nordheim tunneling serves as the dominant tunneling mechanism. [Copyright &y& Elsevier]

Abstract: We report the characteristics of HfO2 films deposited on Ge substrates with and without La2O3 passivation at 250°C by atomic layer deposition (ALD) using La[N(SiMe3)2]3 and Hf[N(CH3)(C2H5)]4 as the precursors. The HfO2 is observed to form defective HfGeO x at its interface during 500°C postdeposition annealing. The insertion of an ultrathin La2O3 interfacial passivation layer effectively prevents the Ge outdiffusion and improves interfacial and electrical properties. Capacitance equivalent thickness (CET) of 1.35nm with leakage current density J A of 8.3×10−4 A/cm2 at V g =1V is achieved for the HfO2/La2O3 gate stacks on Ge substrates. [Copyright &y& Elsevier]