一般高Q值微波介電材料通常具有負值的共振頻率溫度飄移係數(τ_f)，過去的研究者都會添加低Q值的正τ_f的介電材料，使其最終的τ_f值落在±5ppm/℃之間，但不同τ_f對實際陶瓷濾波器的影響到目前為止並沒有人做相關的探討。本研究先用固態燒結法製作Mg(Ti0.95Sn0.05)O3與(Mg0.95Zn0.05)(Ti0.95Sn0.05)O3二種塊體，經微波特性量測，可以在燒結溫度1375℃持溫4小時條件下得到最佳的品質，其介電常數分別為17.81與18.2，Q×f值分別為225,700GHz(at 9.75GHz)與194,740GHz (at 9.72GHz)，與過去文獻比較本研究的Q×f值略低，由XRD分析得知因為具有較多MgTi2O5二次相所造成；此外本研究顯示摻雜微量的Zn2+取代Mg2+會造成Q×f值降低與過去文獻相反。以Mg(Ti0.95Sn0.05)O3添加不同莫耳比例的(Ca0.8Sr0.2)TiO3，以燒結溫度1375℃持溫4小時獲得三種不同τ_f之基板(τ_f=-52.32、-20.25、0.01 ppm/℃) ，在其上網印製作中心頻率為2.45GHz的帶通濾波器，在30℃~90℃間進行S參數量測，結果顯示三種不同τ_f之基板濾波器特性並不會隨著溫度變化而改變，因此摻雜正τ_f之補償材料使溫度飄移係數在±5 ppm/℃的限制並非絕對必要，而且會增加濾波器的插入損失。

High-Q microwave dielectric materials usually have a negative temperature coefficient of resonant frequency (τ_f). In the past, researchers added a low-Q positive τ_f dielectric material to make the final τ_f value fall within ±5 ppm/°C at the cost of reduction of Q factor. Previous to this study, the effect of different τ_f on microstrip components, such microwave filters, had not be fully discussed yet. In this study, Mg(Ti0.95Sn0.05)O3 and (Mg0.95Zn0.05)(Ti0.95Sn0.05)O3 were first prepared by using solid- state sintering method. The most densified bulk for both materials were found under the condition of sintering temperature of 1375 ℃ for 4 hours and the measurements showed that the dielectric constants were 17.81 and 18.2, respectively, and the Q×f values were 225,700 GHz (at 9.75 GHz) and 194,740 GHz (at 9.72 GHz), respectively. XRD analysis showed the existence of MgTi2O5 secondary phase, which accounts for the lower Q×f value of this study, compared with that in past-published reference. In addition, this study also showed that small addition of Zn2+ would decrease Q×f value, contrary to the finding in previous reference. Mg(Ti0.95Sn0.05)O3 was mixed with different molar ratios of (Ca0.8Sr0.2)TiO3, and three different τ_f substrates were obtained at a sintering temperature of 1375 °C for 4 hours (τ_f=-50.32、-20.25、0.01ppm /°C ). Then, band-pass filters were printed on these substrates. The center frequency was 2.45 GHz. S-parameter measurements for temperatures among 30℃ ~90℃were conducted. Contrary to common sense, the results showed that the measured filter characteristics did not varied from 30℃ ~90℃ even for τ_f up to -50.32 ppm /°C. Therefore, the past restriction for τ_f within ±5 ppm/°C seemed unnecessary. In addition, the technique of compensating τ_f always resulting in sacrifice of Q factor, which in term causes the increase of insertion loss of filters.

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