以聚二氧乙烯噻吩為電解質作為 鋁固態電容器之特性研究

Studies on the Characteristics of Aluminum Based Solid State Capacitor with Poly(3,4-ethylenedioxythiophene) as Electrolyte

王鴻明(Hung-Ming Wang)

指導教授 ： 郭欽湊

大同大學/工程學院/化學工程學系所/碩士(2008年)

摘要

摘 要
聚(3,4-二氧乙烯噻吩)導電高分子膜使用在傳統鋁電解電容器上，代替傳統的電解液，作為固態電極，所製造的元件有著體積小、容量大、可靠度高、使用壽命長而且熱安定性佳和優異的高頻性能等特點，在應用方面逐漸受到重視。
本研究即針對在化成鋁箔的基材上使用聚(3,4-二氧乙烯噻吩)作為電解質製作固態電容器的特性探討。使用化學聚合的方法將製備的導電高分子膜附在氧化鋁膜上，只需要在低溫環境下,進行一次的含浸便可以得到具高頻低阻抗特性的電容器。實驗結果發現最適之操作條件在單體含浸中，單體與甲醇混合比例為1：4，55 ℃抽真空至300 ㎜Hg與65 ℃烘箱不抽真空乾燥，對溶劑的揮發並沒有影響。使用氧化劑CB-55 0.3 g在低溫5 ℃ 含浸30 min，高溫聚合溫度為120 ℃ 30 min。且素子不須先預冷，可得最佳之電容特性。電容量(Cs)值為653 μF,散逸因素(DF)值為2.16%、等效串聯電阻(ESR)於100 kHz為8.86 mΩ，洩漏電流為62 μA。本研究完成導電高分子固態電容器與日本製作電容器大廠NIPPON CHEMI-CON PS Series系列特性相當，另外在熱安定性方面，也能通過大氣壓下105 °C、2000 hr的壽命試驗的評估。
本研究所製作的導電性高分子固態電容器其特性效果、阻抗特性值皆較液態電容器的低，且經過高溫壽命實驗後，其電氣特性呈現穩定現象,成功後在市場上有極大的商業價值。

關鍵字

電容器 ； 聚二氧乙烯噻吩

並列摘要

ABSTRACT
Conductive polymer film made of poly(3,4-ethylenedioxythiophene) (PEDOT) is applicable to conventional aluminum solid electrolytic capacitors, and fit to substitute for conventional electrolyte or function as solid state electrolyte, enabling components made thereof to be small sized, high capacitance, highly reliable, long life, thermal stability, and high frequency, and becoming in wider use.
This study is aimed at exploration of related characteristics of PEDOT applied to formed onto the aluminum foil and configured to function as electrolyte for fabricating solid state electrode. A high frequency and a low impedance capacitor could be obtained by utilizing polymerization on prepared conductive polymer film to aluminum oxide film and performing impregnation once at low temperature. Laboratory results show that the most suitable operation conditions for monomer is under impregnation and the proportion of monomer to methanol should be 1:4. No matter it's vacuumed at 300 mmHg at 55℃ or without vacuumed at 65℃, it makes no influence for solvent being evaporated. Putting 0.3 g of oxidant CB-55 under impregnation at the low temperature of 5 ℃for 30 min and setting high temperature polymerization at 120 ℃ for 30 min, the best characteristics of capacitance with capacitance (Cs) of 653 μF, dissipation factor (DF) of 2.16%, equivalent series connected resistance (ESR) of 8.86 mΩ at 100 kHz, and leakage current of 62 μA, could be gained provided that elements were not pre-cooled. In conclusion, this study reveals that the solid state electrolyte fabricated with conductive polymer has equivalent features to those of the NIPPON CHEMI-CON PS Series. Moreover, in terms of manifests thermal stability, it's passed a service life evaluation test conducted at 105 °C for 2000 hours under atmospheric pressure.
The result of this research indicates that conductive polymer based on solid state electrolyte fabricated has much better performance including lower impedance than those of liquid state electrolyte capacitor. In addition, passing through a high temperature service life test, the manifests stable electrical characteristics has certainly brought a significant commercial value in the market.

並列關鍵字

Capacitor ； Poly(3,4-ethylenedioxythiophene)

參考文獻

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