摻雜元素對X8R介電陶瓷微結構與介電性質影響

The Effects Dopants on Dielectric Behaviors and Microstructure of the X8R Materials

楊柏森(Bo-Sen Yang)

指導教授 ： 王玉瑞 ； 王錫福

國立臺北科技大學/工程學院/資源工程研究所/碩士(2009年)

摘要

近年來，積層陶瓷電容常應用於汽車電子元件上，如引擎電子控制裝置(ECU)，防煞車鎖死系統(ABS)與燃料供給程式系統(PGMFI)。這類系統常常必須在嚴酷的環境條件下運作，而符合X7R規格的積層陶瓷電容器不足以應付如此嚴苛的環境，因此基於安全方面上的考量，近來在汽車電子的應用方面，符合電子工業協會（Electronic Industries Association, EIA）標準中X8R規範（-55至150 oC，ΔC/C≦±15%）的介電材料獲得了高度的關注。
主要材料為鈦酸鋇陶瓷粉體，並摻雜數種的摻雜物如氧化鈧Sc2O3、碳酸鎂MgCO3、矽酸鋇BaSiO3、碳酸錳MnCO3、氧化鑭La2O3、氧化鈷Co3O4及氧化鎳NiO，再將此介電材料混合球磨，在還原氣氛下燒結後，再經過退火製程。可鈦酸鋇的性質提升經量測分析後，得介電陶瓷之介電常數>2000與介電損失<2.0%，藉此，可符合EIA標準中的X8R規範並有較佳的緻密性。

關鍵字

鈦酸鋇 ； X8R材料 ； 積層陶瓷電容

並列摘要

In recent years, multilayer ceramic capacitor has been used in the electronic components of automobile, such as ECU (engine electronic control unit), ABS (antilock brake system) module and PGMFI. These electronic components often have to operate in a large temperature variation range, and the X7R multilayer ceramic capacitor is not able to meet this demand. For the sake of safety, the EIA (Electronic Industries Association) has stipulated the standard for X8R characteristic (ΔC/C≦±15% in the temperature range from -55 to 150 degree C) and ceramic materials or compositions meeting this standard have attracted a lot of attention.
The dielectric ceramic composition of the present invention comprises BaTiO3 as the main component and one or more subcomponents. The one or more subcomponents include Sc2O3 , MgCO3, BaSiO3, MnCO3, La2O3, Co3O4 and NiO. The end product may be formed after BaTiO3 and the subcomponent(s) undergo the following steps: (1) Wet mixing using a ball mill (2) Sintering in a reducing atmosphere (3) Annealing. The end product has a dielectric constant >2000 and a dielectric loss< 2.0%. Therefore, the end product can satisfy the X8R characteristic of the EIA standard and is dense enough.

並列關鍵字

BaTiO3 ； X8R materials ； MLCCs

參考文獻

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