Search

Analysis of the anomalous threshold voltage shift of N- and P-MOSFET underflow and reflow of Borophosphosilicate glass films with rapid thermal annealing (RTA) and/or furnace revealed that the shift occurs due to the large amount of donor-like states in SiO2/Si interface. High RTA ramp-rate induced thermal strain, which resulted in the generation of the donor-like interface state. Post-oxide RTA affected polysilicon MOS capacitor performance.

Investigates anomalous interface states of metal-oxide-semiconductor structures induced by rapid thermal post-oxide annealing. Description of the interface states generated by rapid thermal annealing (RTA); Effects of RTA on oxide quality; Changes in the quasistatic capacitance/gate voltage curves before and after negative-bias stress for the samples.

The thermal stability, magnetocaloric effect, and refrigeration capacity (RC) of Gd-based Gd65Fe20Al15-xBx (x=0-7) glassy ribbons have been investigated. A relatively wide supercooled liquid region ΔTx(ΔTx=Tx-Tg) (50-80 K) and large reduced glass transition temperature Trg(Trg =Tg /Tm) (>0.63) are found in Gd65Fe20Al15-xBx glassy ribbons. The distinctive glass transition and sharp crystalline events as well as large values of ΔTx and Trg confirm the excellent glass forming ability of these alloys. The maximal magnetic entropy changes, -ΔSM max, and RC values of the specimens are about 4.80-5.21 J/kg K and 700-800 J/kg under 50 kOe, respectively. These -ΔSM max values are comparable to or even higher than that of some reported bulk metallic glasses. Moreover, the larger RC values are due to the broad ΔSM peak (∼200 K), which is caused by the glassy structure. The large ΔSM and RC values make the Gd-based Gd65Fe20Al15-xBx glassy ribbons attractive candidates for magnetic refrigeration materials. [ABSTRACT FROM AUTHOR]

The magnetocaloric effect (MCE) of the amorphous Fe–Zr–B–M (M=Mn, Cr, and Co) ribbons has been investigated. The MCEs of the Fe90-xZr10Bx (x=5, 10, 15, and 20) ribbons are enhanced with small amounts of boron addition. Furthermore, the Curie temperature of the specimens can be decreased to be about room temperature with appropriate Mn and Cr substitutions, but the MCE performance of the specimens drops only slightly. It is also found that the magnetic entropy change of the Co-substitution series of Fe85-yZr10B5Coy ribbons almost remains constant although the Curie temperature is increased to be about 400 K for y=5. Therefore, for the application of MCE refrigeration at above room temperature, the Fe85-yZr10B5Coy ribbons are preferred due to the constant MCE and the high refrigeration capacity of about 90 J/kg at the magnetic field change of 10 kOe. Moreover, the field dependence of the magnetic entropy change exhibits power dependence for all the studied specimens. In the ferromagnetic range, the exponent is close to 1. In the paramagnetic regime, well above the Curie temperature, the exponent is 2, in agreement with the Curie–Weiss law. [ABSTRACT FROM AUTHOR]

The phase constitution, microstructure, and magnetocaloric effect (MCE) in low-cost iron-based binary Y2Fe17 ribbons have been investigated by using x-ray diffraction, transmission electron microscopy, and measuring their magnetic properties, respectively. It is found that the crystal structure of the as-spun ribbons is hexagonal Th2Ni17 type with the wheel speed ranging from 10 to 40 m/s because of the week glass-forming ability. The ribbon prepared at 20 m/s shows a magnetic entropy change of 1.89 J/kg K under magnetic field change of 10 kOe. The low-cost, easy-synthesis, and considerable MCE properties make Y2Fe17 alloys in ribbon form as suitable room temperature MCE materials. [ABSTRACT FROM AUTHOR]

Magnetic properties and microstructure of directly quenched Nd9.5Fe75.5-xMxB15 (M=Mo, Nb, Ta, Ti, V, and Zr; x=0–4) bulk magnets in rod form with a diameter of 0.7 mm have been studied. The substitution of the selected refractory elements for Fe in the Nd9.5Fe75.5MxB15 alloy can suppress the formation of the soft phases, including Nd2Fe23B3 and one unknown phase, leading to the presence of a large amount of the Nd2Fe14B phase. Besides, the grain size at the core side of the rods is refined from a micrometer scale for a ternary magnet to 50–120 nm for the magnets with refractory element substitution. As a result, the magnetic properties are improved remarkably from Br=5.0 kG, iHc=1.0 kOe, and (BH)max=1.7 MG Oe for a ternary magnet to Br=5.7–6.5 kG, iHc=2.0–14.6 kOe, and (BH)max=3.1–8.7 MG Oe for refractory element substituted magnets. The optimal magnetic properties of Br=6.5 kG, iHc=10.3 kOe, and (BH)max=8.7 MG Oe can be achieved in the Nd9.5Fe72.5Ti3B15 magnet, while the highest coercivity of iHc=14.6 kOe, with Br=5.9 kG and (BH)max=7.4 MG Oe, is obtained in the Nd9.5Fe71.5Nb4B15 magnet. [ABSTRACT FROM AUTHOR]

Magnetic properties, phase evolution, and microstructure of melt-spun (Sm1-xPrx)Co7-yHfyCz ribbons have been investigated. For (Sm1-xPrx)Co7-yHfy (x=0–1; y=0.1–0.3) ribbons, the magnetization increases, but coercivity decreases, with increasing Pr content. However, the phase constitution and microstructure have not been influenced by modifying Pr content x. The attractive magnetic properties of Br=6.5 kG, iHc=6.1 kOe, and (BH)max=7.2 MG Oe could be obtained for (Sm0.8Pr0.2)Co6.9Hf0.1 ribbons. A slight addition of C in (Sm0.8Pr0.2)Co6.9Hf0.1Cz (z=0.06–0.14) ribbon not only refines the microstructure, but also induces nanoscale fcc-Co precipitation in the matrix, leading to the stronger exchange-coupling effect between magnetic grains and the enhancement of remanence and magnetic energy product. As a result, the improved magnetic properties of Br=7.1 kOe, iHc=8.5 kOe, and (BH)max=11.2 MG Oe can be achieved for (Sm0.8Pr0.2)Co6.9Hf0.1C0.12 ribbons. [ABSTRACT FROM AUTHOR]

Effects of Co content on the magnetic properties and microstructure of melt-spun [(Fe1-xCox)0.675Pt0.325]84B16 (x=0–0.5) and [(Fe1-yCoy)0.725Pt0.275]85B15 (y=0 and 0.3) nanocomposite ribbons have been investigated. The substitution of Co for Fe in [(Fe1-xCox)0.675Pt0.325]84B16 ribbons enhances the coercivity (iHc) from 7.5 kOe for x=0 to 10 kOe for x=0.3, due to the formation of ordered L10-(Fe,Co)Pt phase with higher anisotropy field. The effect of Co substitution for Fe in [(Fe1-yCoy)0.725Pt0.275]85B15 series ribbons is similar to that in [(Fe1-xCox)0.675Pt0.325]84B16 system. Interestingly, larger magnetization could be obtained by decreasing the boron and Pt content simultaneously. Moreover, L10-(Fe,Co)Pt phase provides [(Fe0.7Co0.3)0.725Pt0.275]85B15 ribbons sufficient high coercivity iHc=5.4 kOe, resulting in a remarkable enhancement of energy product from 10.0 MG Oe for Co-free ribbons to 15.7 MG Oe for ribbons with y=0.3. [ABSTRACT FROM AUTHOR]

Magnetic aftereffect and surface magnetic domain structure of (Fe0.675Pt0.325)100-xBx(x=12–20) nanocomposites have been investigated for correlating with their corresponding phases and magnetic properties. Exchange-coupling effect between grains is present for all the studied ribbons as evidenced by Henkel plot. The volume fraction of magnetically soft phases decreases with increasing B concentration from x=12 to x=18. It leads to the reduction in the activation volume of the reverse domain. Among all samples, the (Fe0.675Pt0.325)82B18 ribbon having the highest intrinsic coercivity (iHc) exhibits minimum value in activation volume V=1.1×10-18 cm3, because it possesses the least volume fraction of the magnetic soft phases, i.e., Fe2B or Fe3B phases. Magnetic force microscopy studies reveal the magnetic domain structures of the ribbons, confirming the existence of strong exchange coupling between magnetic grains. [ABSTRACT FROM AUTHOR]

Presents a study which focused on observations on the phase transformation and its effect on the resistivity of tungsten silicon films prepared by low-pressure chemical vapor deposition. Methods; Results; Discussion.