鐵鉿氧軟磁薄膜之微結構與磁性質分析及功率電感與鐵鉿氧軟磁薄膜整合之性能

Microstructure and Magnetic Properties of Fe-Hf-O Soft Magnetic Films and the Performance of Integrated Inductor with the Fe-Hf-O Films

王宗聖(Zong-Shenq Wang)

指導教授 ： 杜正恭

國立清華大學/工學院/材料科學工程學系/碩士(2011年)

https://doi.org/10.6843/NTHU.2011.00334

摘要

近年來，輕、薄、短、小蔚然成為消費性電子產品的發展趨勢，若將鐵磁薄膜與電感整合，有助於電感尺寸的縮減以降低電子產品中直流/直流電源轉換器(DC/DC converter)的體積。本研究之目的為開發鐵磁薄膜並將其與功率電感結合。第一部份，以直流磁控濺鍍系統在O2與Ar的氣氛下，成功製備具奈米晶與非晶之混合相的Fe-Hf-O薄膜。當通入的氧流量為1.2 sccm時，成份為Fe58.8Hf13.1O28.1，其飽和磁化量約為10.6 kG，電阻率為254 μΩ-cm，導磁率為250。此外，在氧流量固定為1.2 sccm時，探討Fe-Hf-O薄膜的厚度對磁性質之影響。當膜厚由0.5 μm增加到5.5 μm時，其飽和磁化量與電阻率無顯著的變化，矯頑場與導磁率分別由 5 Oe 和300下降到0.5 Oe 與160。
在第二部份，將不同厚度的FeHfO與去除上遮蔽鼓的工字型電感整合，整合型電感的感值隨膜厚增加，感量的提升由3 % 提升到25%，且直流重疊電流(DC bias current)之表現也有所改善。另外，更進一步將整合型電感的膜厚固定為5.5 μm，探討繞線圈數為7, 9, 11和15圈時，對感值與直流重疊電流的影響。當繞線圈數增加時，感值隨之提升，但直流重疊電流卻因而下降，整合型電感的繞線圈數與膜厚分別為11圈與5.5 μm時，感值與直流重疊電流為1.34 μH和1.76 A，可適用於直流/直流電源轉換器。

關鍵字

軟磁薄膜 ； 鐵鉿氧 ； 導磁率 ； 功率電感

並列摘要

Soft magnetic thin films integrated to magnetic component, i.e. inductor, are considered as a potential solution to meet increasing demand for smaller dimension and light weight power conversion devices in portable electron products. In this study, the influences of oxygen flow rate on magnetic and high frequency properties of as-deposited Fe-Hf-O thin films were analyzed. These films exhibited mixed phases of α-Fe nanograins and amorphous HfO2 phase, showing nanocrystalline structure and soft magnetic properties. The Fe58.8Hf13.1O28.1 film with the optimum O2 flow rate of 1.2 sccm showed high saturation magnetization of 10.6 kG, high resistivity of 254 μΩ-cm, and flat μ' characteristics of 250 up to 1 GHz. The thickness effects on the characterization of Fe-Hf-O film with the O2 flow rate of 1.2 sccm were also investigated. The composition, resistivity, and saturation magnetization nearly maintained constant with varying thickness. As the film thickness increased from 0.5 to 5.5 μm, the coercivity (HC) decreased to a minimum value of 0.5 Oe and complex permeability gradually declined from nearly 300 to 160.
In addition, a novel structure was proposed to incorporate commercially available inductor with as-fabricated Fe-Hf-O films of 0.5, 1.1, 3.3, and 5.5 μm. The inductance of integrated inductors increased from 3 % to 25 % with Fe-Hf-O film. The DC current characteristic of integrated inductor was improved by a thicker film. The performance of integrated inductors with 5.5-μm FeHfO and various coil turns of 7, 9, 11, and 15 was discussed. The integrated inductor with coil turns of 11 and 5.5 μm thick Fe-Hf-O film displayed high inductance of 1.34 μH and superimposed current of 1.76 A, exhibiting potential applications in DC/DC converter.

並列關鍵字

Soft magnetic thin film ； Fe-Hf-O ； permeability ； inductor

參考文獻

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