Preparation And Performance Study Of High-frequency Micro-magnetic Inductor Based On FeCoB Interlayer Coupling Three-layer Fil

With the progress of science and technology and the rapid development of electronic information technology,high-frequency soft magnetic films have been more and more widely used in the microwave field.FeCoB soft magnetic film material not only has relatively high saturation magnetization,but also has good thermal stability,and it is easy to induce its anisotropy H_K Therefore,the ferromagnetic resonance frequency f_rof the magnetic film can be greatly improved,so that its operating frequency band can be increased to above GHz.Inductor is one of the three passive components.Its development trend is changing towards miniaturization,high-frequency and integration.It is widely used in high-frequency circuits and wireless communications.However,the performance of the inductor deteriorates sharply at high frequency,which can’t meet people’s needs,so we urgently need a high frequency integrated inductor.The combination of planar spiral inductors and magnetic thin films can effectively improve the performance of inductors,increase the inductance and Q value,and make the miniaturization,integration and high-frequency requirements of inductors can be successfully solved.So we combine interlayer exchange coupled FeCoB trilayer film as magnetic material with planar spiral inductor to study the high-frequency performance of micro-core planar spiral inductor.The main contents of the paper are as follows:(1)This thesis briefly introduces the HFSS simulation software and its simulation process,and uses the HFSS simulation software to simulate and analyze whether the inductance Q value and the inductance L value are affected by the presence or absence of magnetic core and structural parameters of the coil,analyze its influence rules and find the optimal parameters for the preparation of the inductor,which provides an important basis for the subsequent design and preparation of the inductor.(2)FeCoB/Ru/FeCoB trilayer films were grown by magnetron sputtering,and their properties were studied and analyzed.The ferromagnetic resonance frequency f_rof the films reached 17 GHz,and the real part permeability(μ′)It is kept above 15 and has excellent high frequency performance,which meets the requirements of the application of the magnetic core layer in the integrated inductor on the plane spiral high frequency chip.(3)The layout of the integrated planar spiral inductor is designed,and the photolithography,electroplating and etching steps in the preparation process of the inductor are deeply explored.Then,by studying,analyzing and solving various problems in the process,the preparation process of the inductor is continuously optimized.Finally,the overall process of the integrated inductor on the micro-core plane spiral is summarized,and the inductors with different conditions and parameters are successfully prepared.(4)Agilent N5224A vector network analyzer and microwave probe platform were used to test the hollow core inductor and the integrated inductor on the micro-magnetic chip we prepared,and the test results of the inductor were analyzed.The test results show that the addition of magnetic core can effectively improve the performance of the inductor.The inductance value L is increased by 42.8%from 1.2 n H to 2.1 n H,and the inductance value remains stable below 8 GHz.The operating frequency is reduced by 1GHz,and the Q value is reduced from 12 to 8.2,which is reduced by 31.7%.The increase of coil turns,the reduction of coil width and the reduction of wire spacing can improve the inductance value L,which is consistent with our simulation results.