本研究利用網版印刷技術，於雙面銅箔基板上，印刷高固含量之磁膠，並搭配冷均壓製程，製作具優異電氣特性之平面電感。
為解決合金粉末電阻率低，導致渦流損失過大之問題，本研究於粉體中添加高分子有機載體，可於粉體顆粒表面形成一絕緣層；接著，加入少量之稀釋劑調整流變性質，製備一高固含量複合材料之漿料，以符合網版印刷中所需之流動特性。
而為改善磁力線集中，致使容易磁飽和之問題，將於元件中央利用機械鑽孔生成中柱，亦由磁性材料填入，藉此增加貫通鐵芯之主磁通，使磁力分布更為均勻，同時也能提高電感值。
使用此製程方法製作之電感元件，感值幾乎達1μH以上；於頻率1MHz下，擁有10~13 之品質因子；且多數樣品可於電流2.5安培條件下，衰退量仍維持在5%內，符合產品實際應用。此外，亦使用Ansys公司發行之低頻電磁場模擬器--Maxwell軟體，模擬靜磁場環境，分析元件之線圈幾何形狀及不同磁膠配方對電感量及磁力線分布等資訊，利於尋找最佳化參數。
本研究除了實驗亦配合模擬之結果，兩者相輔相成，能有效找到平面電感器之最佳化參數，另也可以比較出兩者之差異。

In this study, a planar inductor with excellent electrical characteristics was successfully prepared by screen printing of high solid content alloy magnetic pastes onto copper clad laminates (CCL), and then cold-isostatic pressing to increase the packing density. In order to solve the problem of low electrical resistivity of alloy powder, resulting in excessive eddy current loss for power inductor application, an epoxy resin vehicle was added to form an insulating layer on the surface of the mixture of FeSiCr alloy and carbonyl iron powders. A high solid content alloy magnetic paste was then prepared by adding a small amount of diluent to meet the flow characteristics required in screen printing.
As the magnetic flux density for an inductor is concentrated, magnetic saturation is easily achieved. The center column generated by mechanical drilling in the center of the planar inductor was filled with magnetic paste to make the distribution of magnetic flux density more uniform, which prevented the magnetic saturation. At the same time, the inductance value can be increased.
The planar inductor of size 8.5mmx7.0mmx0.4mm with an inductance value of about 2.7μH at 1MHz, a quality factor of 10 to 13, and the degradation rate of about 5% at a DC bias of 2.5A can be successfully prepared in this study. In addition, Maxwell software, a low-frequency electromagnetic field simulator issued by Ansys, was used to simulate the effects of the coil geometry and magnetic paste formulation on the static magnetic field environment, magnetic flux density distribution, and the electromagnetic properties of the planar inductors, which is helpful to find the optimal parameters. The differences between the simulation and the experimental results for the planar inductors were compared, suggesting that the deviation between them was within 6%.

[1] Ouyang, Z., & Andersen, M. A. (2013). Overview of planar magnetic technology—Fundamental properties. IEEE transactions on Power Electronics, 29(9), 4888-4900.

[2] 粉末冶金技術手冊. (1994). 中華民國產業科技發展協進會出版.

[3] McLyman, C. W. T. (2017). Transformer and inductor design handbook: CRC press.

[4] TDK. (April 25, 2014). Wireless charging for mobile devices and electric vehicles.

[5] RICHTEK. 電感之種類與其特性分析.

[6] Chen, F., & Wang, Y. (2014). Investigation of glass forming ability, thermal stability and soft magnetic properties of melt-spun Fe83P16− xSixCu1 (x= 0, 1, 2, 3, 4, 5) alloy ribbons. Journal of alloys and compounds, 584, 377-380.

[7] Wang, X., Li, J., Zhang, N., Xie, J., Liang, D., & Deng, L. (2016). Evolution of hyperfine structure and magnetic characteristic in Fe-Si-Cr alloy with increasing heat treatment temperature. Materials & Design, 96, 314-322.

[8] Yang, R., Liang, W., Chen, C., & Choi, S.-T. (2014). Electromagnetic and microwave absorbing properties of raw and milled FeSiCr particles. Journal of Applied Physics, 115(17), 17B536.

[9] Zhang, X., Liang, D., Wang, X., & Zhou, P. (2014). The evolution of microstructure and magnetic properties of Fe–Si–Cr powders on ball-milling process. Journal of alloys and compounds, 582, 558-562.

[10] Magazine, T. Inductor - Part 3 Inductor Types and Manufacturing Methods.

[11] Wyatt, O. H., & Dew-Hughes, D. (1974). Metals, ceramics and polymers: An introduction to the structure and properties of engineering materials(Book). London and New York, Cambridge University Press, 1974. 650 p.

[12] Nagaoka, H. (1909). The inductance coefficients of solenoids. Journal of the College of Science, 27(3), 31.

[13] Mohan, S. S., del Mar Hershenson, M., Boyd, S. P., & Lee, T. H. (1999). Simple accurate expressions for planar spiral inductances. IEEE Journal of solid-state circuits, 34(10), 1419-1424.

[14] Wheeler, H. A. (1928). Simple inductance formulas for radio coils. Proceedings of the institute of Radio Engineers, 16(10), 1398-1400.

[15] Rosa, E. B. (1906). Calculation of the self-inductance of single-layer coils: US Government Printing Office.

[16] TDK. (2011). Multilayer Chip Inductor MLG0402Q/MLG0603P.

[17] Muhlethaler, J., Biela, J., Kolar, J. W., & Ecklebe, A. (2011). Improved core-loss calculation for magnetic components employed in power electronic systems. IEEE transactions on Power Electronics, 27(2), 964-973.

[18] Kollár, P., Birčáková, Z., Füzer, J., Bureš, R., & Fáberová, M. (2013). Power loss separation in Fe-based composite materials. Journal of magnetism and magnetic materials, 327, 146-150.

[19] Lu, J., Jia, H., Wang, X., Padmanabhan, K., Hurley, W. G., & Shen, Z. J. (2010). Modeling, design, and characterization of multiturn bondwire inductors with ferrite epoxy glob cores for power supply system-on-chip or system-in-package applications. IEEE transactions on Power Electronics, 25(8).

[20] Waffenschmidt, E., Ackermann, B., & Wille, M. (2005). Integrated ultra thin flexible inductors for low power converters. Paper presented at the 2005 IEEE 36th Power Electronics Specialists Conference.

[21] Reed, J. S. (1995). Principles of ceramics processing.

[22] 林承逸. (2017). 自我修復環氧樹脂之研究. (碩士), 東海大學, 台中市. Retrieved from https://hdl.handle.net/11296/4748k3

[23] 徐福啟. (2009). 以鐵氧磁體/環氧樹脂複合材料製備可撓式電感之研究. (碩士), 國立成功大學, 台南市. Retrieved from https://hdl.handle.net/11296/wydccd

[24] Szostak, R., Nair, V., & Thomas, T. L. (1987). Incorporation and stability of iron in molecular-sieve structures. Ferrisilicate analogues of zeolite ZSM-5. Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 83(2), 487-494.

[25] Szostak, R., & Thomas, T. (1986). Crystallization of ferrisilicate molecular sieves with a sodalite structure. Journal of the Chemical Society, Chemical Communications(2), 113-114.

[26] 塗謹豪. (2015). 具高品質因子之微型螺旋電感器研發. (碩士), 國立中山大學, 高雄市. Retrieved from https://hdl.handle.net/11296/nswtrd

[27] 齐立荣, 李海波, & 朱义胜. (2007). 平面螺旋电感参数的计算和仿真研究. 林区教学(2), 57-58.

[28] Jenei, S., Nauwelaers, B. K., & Decoutere, S. (2002). Physics-based closed-form inductance expression for compact modeling of integrated spiral inductors. IEEE Journal of solid-state circuits, 37(1), 77-80.

[29] Kowase, I., Sato, T., Yamasawa, K., & Miura, Y. (2005). A planar inductor using Mn-Zn ferrite/polyimide composite thick film for low-Voltage and large-current DC-DC converter. IEEE Transactions on Magnetics, 41(10), 3991-3993.

[30] Fukuda, Y., Inoue, T., Mizoguchi, T., Yatabe, S., & Tachi, Y. (2003). Planar inductor with ferrite layers for DC-DC converter. IEEE Transactions on Magnetics, 39(4), 2057-2061.

[31] Brandon, E. J., Wesseling, E. E., Chang, V., & Kuhn, W. B. (2003). Printed microinductors on flexible substrates for power applications. IEEE transactions on Components and Packaging Technologies, 26(3), 517-523.

[32] Sugawa, Y., Ishidate, K., Sonehara, M., & Sato, T. (2013). Carbonyl-Iron/Epoxy Composite Magnetic Core for Planar Power Inductor Used in Package-Level Power Grid. IEEE Transactions on Magnetics, 49(7), 4172-4175.