高效能微型電感之研究

Study of High Performance Micro-Inductor

黃繼正(Ji-Zheng Huang)

指導教授 ： 葉鳳生 ； 吳清沂

國立清華大學/電機資訊學院/電子工程研究所/碩士(2008年)

摘要

近年，微機電技術在被動元件上之應用極為廣泛，以微型電感器而言主要朝著高Q值與高電感值之原件特性表現發展。本論文分別設計與製做射頻與低頻兩種平面電感器，目的為得到高電感值與高Q值之原件特性表現。其一射頻電感器主要利用微機電技術在玻璃晶片上設計製作懸浮雙層圓形螺旋電感器，使用厚光阻與銅電鍍製程完成線圈之製做。再以hp8510C網路分析儀進行45MHz至20.045GHz之高頻S參數量測，藉由ADS軟體計算萃取原件之電感值，Q值與等效實部串聯電阻等特性。得到最大Q值47.4，電感值3.12nH與共振頻率達15.6GHz之高表現特性。第二部份為低頻電感器，使用射頻懸浮雙層圓形螺旋電感線圈相同結構，包覆低溫電鍍製程的鎳鐵(Ni80Fe20)軟磁性材料以封閉其磁路，降低磁通量之損失。使用hp 4284A LCR Meter量測10KHz至100KHz之低頻電感特性，取得包覆鎳鐵之雙層圓形螺旋電感之電感值Ls為619nH與串聯電阻Rs，進而比較包覆磁性材料前後之電感提升效果。
射頻電感中，玻璃基材的選用確實降低了基板損耗以及用空氣當絕緣的懸浮結構有效提高Q值，相較其他射頻電感器我們達到47.4之高Q值特性表現。而低頻電感，我們以封閉磁路之包覆鎳鐵構想，有效減少磁通量的損失，提高單位面積電感值達448.55nH/mm2。

關鍵字

電感值 ； 品質因素

並列摘要

In recent years, the high quality factor and high inductance are the main tendency in micro-inductors. In this study, we designed and fabricated RF-inductors and low-frequency inductors, respectively. It is expected to obtain high quality factor and high inductance characteristics. For RF-inductors, we designed and fabricated a suspended double-layer circular spiral inductor on glass substrate by using MEMS technology. Electroplating process and thick photoresist technology were be used to fabricate copper coils. The glass substrate were be used to reduce substrate loss and parallel parasitic effects. The double-layer suspended inductor structure can reduce the capacitive coupling with the substrate effectively and achieve a large inductance per unit area. The S-parameters of RF-inductors were measured in the frequency range from 45 MHz to 20.045 GHz by using hp 8510C vector network analyzer, and then extracted inductance, quality factor and resistance of device by ADS software. It is found that maximum quality factor of 47.7 with an inductance of 3.12 nH and resonance frequency of 15.6 GHz. Compared with other RF-inductors, the performance of quality factor of above suspended double-layer circular spiral inductor is relatively excellent. For low-frequency inductors, Ni80Fe20 alloy is used as the magnetic core material to mantle suspended double-layer circular spiral inductor to reduce loss of magnetic flux. The series inductance and series resistance has been measured using hp 4284A LCR Meter in the frequency range from 10 KHz to 100 KHz. The series inductance value has been achieved 619 nH and 448.55 nH/mm2. Compared with air magnetic core, the use of Ni80Fe20 alloy and closed magnetic path increase inductance value 97.69 times.

並列關鍵字

inductance ； quality factor

參考文獻

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