Nanocrystalline FeCoHf films with Hf composition gradient were prepared by gradient sputtering method at room temperature. A uniaxial magnetic anisotropy with high anisotropy field Hk up to 547Oe was achieved after magnetic annealing with external field along the gradient direction. Ultrahigh ferromagnetic resonance frequency over 7GHz was obtained in magnetic annealed gradient sputtered films. The origin of ultrahigh ferromagnetic properties in gradient sputtered films is discussed.

TiO2 nucleated anorthite‐based glass‐ceramics were fabricated from glass powders. After sintering and crystallization heat treatment, various physical properties, including apparent bulk density and water absorption, were examined to evaluate the sintering behavior of anorthite‐based glass‐ceramic. Results showed that the complete‐densification temperature for specimens was as low as 900°C. Sufficient crystallization was achieved by subsequently raising the firing temperature to 950°C, and the dielectric quality factor was promoted to the maximum value. Contents of nucleating agent (TiO2) played an important role in the dielectric constants. The crystallinity was controlled by raising the firing temperature at a constant heating rate. The degree of crystallization affected the dielectric properties of sintered glass‐ceramics. At the resonant frequency of 10 GHz, anorthite glass‐ceramics with 5 wt% TiO2 possessed the lowest permittivity of 8 and exhibited appropriate dielectric properties as compared with those with B2O3 and 10 wt% TiO2.

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Ferrimagnetic Mn4N films were deposited on Si (100) substrate by dc reactive magnetron sputtering from sintered Mn target. Highly (002) textured Mn4N ordered phase is formed in situ at studied substrate temperatures of 150–250 °C without further annealing. Anomalous perpendicular magnetoanisotropy exists in these face-centered cubic films with larger coercivity measured perpendicular to the film (2000–3000 Oe) than that parallel (1100–1300 Oe), as is the remanence. Coercivity in either direction decreases, while the saturation flux density (from 240 to 610 G) increases with increasing substrate temperature. The anomalous perpendicular magnetoanisotropy is attributed to (1) the stress-induced anisotropy due to in-plane tensile stress coupled with a reverse magnetostriction, and (2) the shape anisotropy due to columnar grain structure.

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