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With the development of switching power supply and electronic technology, the demand for portable electronics is constantly moving towards miniaturization, high-frequency, and low-power loss. This demand has put forward new requirements and challenges for the performance of multilayer chip power inductor. FeSiCr iron-based soft magnetic materials are widely used in the preparation of high-quality multilayer chip power inductor due to their higher magnetic permeability, quality factor Q, and oxidation resistance. However, the sintering conditions of the FeSiCr material have a significant impact on the performance of the multilayer chip power inductor. Currently, few of the reported study have considered the influence of oxygen partial pressure on the performance of multilayer alloy chip power inductor during sintering process. This paper studied the influencing factors of atmosphere sintering pretreatment temperature and time, sintering temperature and oxygen partial pressure during sintering process, based on the multilayer chip power inductor with the size of 201610. The formation mechanism of the influence curves has been comprehensively analyzed theoretically, and Maxwell FEM simulation was used to obtain the magnetic density distribution of the inductor. Finally, the best sintering conditions of the FeSiCr multilayer chip power inductor have been found. According to the comparative experimental under different sintering conditions, the following conclusions can been obtained: the appropriate adhesive discharge temperature and time are 350℃ and 60 minutes, respectively, the optimal sintering temperature is around 750 ℃, the optimal temperature rise rate is 5℃/min. While the oxygen partial pressure is about 6.5%, the multilayer inductor can obtain excellent electrical properties. [ABSTRACT FROM AUTHOR]

• A novel hybrid amorphous soft magnetic composite (SMC) for MHz power applications is fabricated using amorphous powders of ultrafine spherical FeSiBCr and submicron FeBP powders. • The regularly spherical particles of submicron amorphous FeBP powders are found to occupy the gaps between the micron-sized FeSiBCr amorphous powders. • The magnetic loss of the soft magnetic composite mixed with only 1 wt% submicron amorphous FeBP particles is just 511 kW/m3 at 30 mT/1 MHz, and the permeability of DC bias superposition under 100 Oe reaches 90%. • The soft magnetic composite constructed by the pure submicron amorphous FeBP particles also shows excellent magnetic properties within a few hundred MHz region, with the permeability of 4–6 and the low loss tangent of only 0.019 at 200 MHz and 0.05 at 500 MHz. • This amorphous soft magnetic composite exhibits a great potential for the applications in wide band gap semiconductor switching power supplies, RF inductors and chips. A novel hybrid amorphous soft magnetic composite (SMC) for MHz power applications is fabricated using amorphous powders of ultrafine(<10 μm) spherical FeSiBCr and submicron(100 nm∼1 μm) FeBP powders. The submicron amorphous FeBP powders are found to occupy the gaps between the micron-sized FeSiBCr amorphous powders, enabling one to enhance the density and magnetic properties (permeability and loss) of the composite in a MHz frequency range. The magnetic loss of the soft magnetic composite mixed with only 1 wt% submicron amorphous particles is just 511 kW/m3 at 30 mT/1 MHz, and the permeability of DC bias superposition under 100 Oe reaches 90%. In addition, the permeability of the hybrid soft magnetic composite and the submicron amorphous composite reach 20 and 5, and the loss tangent is only 0.03–0.08 and 0.02 in 100 MHz region, respectively. This amorphous soft magnetic composite exhibits a great potential for the applications in wide band gap semiconductor switching power supplies. [ABSTRACT FROM AUTHOR]