本研究是以Ba(Mg1/3Nb2/3)O3陶瓷材料為主體，對其B-site陽離子做少量同價取代與非劑量比(少量異價取代)的實驗。其中同價取代是以二價鈷離子少量從0.01到0.07取代Ba(Mg1/3Nb2/3)O3陶瓷材料中的二價鎂離子，並分別利用持溫4小時後自然爐冷與不持溫後每分鐘2oC慢速降溫，兩種不同製程條件來觀察微結構、有序程度與微波介電性質的變化。由實驗結果發現少量Co2+ 取代Mg2+ 可以促進晶粒的成長與有序程度提升，進而使Q x f 值上升，且在取代量為0.05 mole 時有序程度從原本沒有取代時62%提升到92%，Q x f 值也從14,000 GHz提升到43,000 GHz，而和先前研究大範圍取代量中性質最優異成分點(0.5 mole，Q x f = 40,000)，性質表現相近。此外利用慢速降溫的方式可以使有序程度再提升到95%，進而使Q x f 值提升到60,000 GHz。
而在非劑量比(少量異價取代)的實驗中，是在B-site些微偏離Ba(Mg1/3Nb2/3)O3其B-site為1:2的組成，但仍維持在有序且單一相的情況下，利用B-site 陽離子微量的不足或過剩的情況，促進了燒結與擴散，使晶粒大小、有序程度與Q x f 值皆大幅提升，其中在Ba(Mg0.97Nb2.012)1/3O3的組成時，其Q x f 值從原本Ba(Mg1Nb2)1/3O3的14,000 GHz提升到116,000 GHz，有序程度從 62%提升到95%。
此外從本研究結果可知，不論是少量同價取代或是非劑量比(少量異價取代)，晶粒大小與有序程度皆是影響Q x f 值的重要的因素，而在性質的表現上非劑量比(異價取代)又比同價取代還要好，此外若能使用不同的燒結條件控制降溫速率，進而促進有序程度或密度的提升，則可以獲得一較高的Q x f 值。

There are two major experimental subjects in this study. The small amount of Co2+ substitution on Ba(Mg1/3Nb2/3)O3 and non-stoichiometry of Ba(Mg1/3Nb2/3)O3 were both investigated. The experimental results show that the ordering degree, mean grain size, and quality factor were increasing by small amount Co2+ substitution from x = 0.01 to x = 0.05, and could get an optimal value of quality factor at x = 0.05 (S = 92%, Q x f = 40,000 GHz). Moreover, through decreasing the cooling rate, the ordering degree increased 3% and the relative density increased 2% which increased the quality factor. At x = 0.05, the ordering degree is 95% and Q x f is 59,000 GHz.
The experimental results of non-stoichiometry of Ba(Mg1/3Nb2/3)O3 indicated that through the slight deviation of B-site cation, that could obtain a great quality factor. When the composition located in Ba(Mg0.97Nb2.012)1/3O3, the ordering degree is 92% and the Q x f is 116,000GHz.
In this study, the results demonstrated that the quality factor is depending on ordering degree and grain size. The quality factor increase while the ordering degree and mean grain size increased. The quality factor is better in non-stoichiometry of Ba(Mg1/3Nb2/3)O3 than small amount of Co2+ substitution of Ba(Mg1/3Nb2/3)O3. In addition, if it could change the sintering conditions to control the cooling rate that will have a higher quality factor.

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