近年高頻行動通訊和無線區域網路(LAN)的普遍使用，如：藍芽和高頻射頻(RF)的系統所使用的元件為了在高頻模組使用，而逐漸往小體積的尺寸去生產。這應用於高頻材料系統的需求必須具備低介電常數(low dielectric constant, εr)、高品質因子(high quality factor, Q f)的特性，因此目前使用低溫共燒陶瓷製成的技術開發的材料，為了能在低溫的條件下和銅膠共燒生產，是產業相當重視的議題。
本論文主要在研究CaMaSi2O6透輝石相之玻璃陶瓷系統的合成，此系統添加ZrO2作為成核劑對相及電性上的影響，隨著ZrO2的添加使得材料主體有不錯的燒結緻密性，在5.05mol% ZrO2添加到透輝石主相中，有最好的密度值在3g/cm3左右。由XRD發現添加不同ZrO2成核劑後有明顯的透輝石相和T-ZrO2出現，且隨著ZrO2的增加T-ZrO2的峰值越強。在SEM微觀下也觀察到無添加成核劑的透輝石主相仍以散亂的玻璃態為主，有添加成核劑的主相有明顯的結晶成長，氧化鋯的添加確實有作為異質成核的功效，能降低核成長的自由能，另外由BEI影像中發現有白點顆粒的析出，利用EDS分析後得知有T-ZrO2的形成是由於Ca和Mg元素固溶到Zr中，導致氧化鋯由M相轉T相的變化。在電性上看到介電常數基本上都小於10在低介電常數的範圍，而有結晶成長的透輝石主相，品質因子(Qxf)相對有比較高的提升，在5.05 mol% ZrO2量添加，有較好的品質因子表現為7310 GHz。
而後為了使透輝石相玻璃陶瓷的材料系統能應用在LTCC製程下和卑金屬電極共燒，試著改變不同燒結氣氛對添加5.05 mol% ZrO2在透輝石主相中，比較在一般大氣與氮氣下燒結結果的差異。在電性部分品質因子的數值在氮氣燒結下明顯降低至3330 GHz。推測原因，從XRD分析發現在氮氣下燒結的試片有峰值寬化現象，是由於氮氣下燒結的試片，晶體內部有較多的空缺形成而造成晶格內的應變值較大，另外再由XPS分析證明透輝石主相有明顯被還原的趨勢，因此可知熱處理後的玻璃陶瓷在缺氧的氮氣氣氛下燒結而產生被還原的現象，使得材料半導化而影響電性表現。
因此為了改善氮氣下燒結的特性，在第三部份我們試著在添加ZnO作為抗還原劑依不同比例分析ZnO在透輝石相中的變化，由XRD發現隨著ZnO的添加量從0.5到4 mol%的添加範圍內，基本上仍維持著透輝石相和T-ZrO2,而在6、8 mol%後有R-Zn2SiO4的形成，但這些相態都屬於低介電常數的性質，因此介電常數(εr)仍維持在7~8之間。而在3.31mol%開始時單位晶胞有逐漸膨脹的趨勢，推測大量的Zn佔據了Si的位置，因Zn離子半徑大於Si而造成主相晶體畸變的現象，這晶體膨脹的趨勢和品質因子的提升一致，而由XPS分析證實在3.31~8mol%的ZnO添加，透輝石主相的鍵結能，確實有往高的電子束縛能偏移，證實晶體畸變使氧不易脫離而產生抗還原的作用。ZnO的添加確實有助於氮氣下改善品質因子的特性，在4 mol%的ZnO添加有最佳的電性表現，介電常數(εr)為7.25、品質因子(Qxf)為8330。

High-frequency mobile communication and wireless local area networks (LAN) are widespread used in recent years. For instance, components use in the systems of bluetooth or high-frequency radio frequency (RF) are produced based on miniature size in order to make them use in high-frequency modules, which require low dielectric constant (εr) and high quality factor (Q×f). Hence, the materials, which are developed by means of Low Temperature Co-fired Ceramics (LTCC), are an important research issue in recent years.
This study aims to research on the composition of glass-ceramic system of CaMaSi2O6 Diopside. ZrO2 added in this system is acting as nucleation agent on electricity and Diopside phase. Moreover, the addition of ZrO2 makes the main body of the material has good densification after sintering. When 5.05mol% ZrO2 is added to Diopside phase, the best density value is about 3g/cm3. By means of XRD, it is found that addition of different ZrO2 nucleation agents make Diopside phase and T-ZrO2 obviously appear, and peak values of T-ZrO2 will be higher as the increase of ZrO2 added. By means of SEM, it is observed that the Diopside phase without nucleation agent is mainly in disordered glassy state and there is obvious crystal growth in the phase with the addition of nucleation agent. The addition of ZrO2 exactly increases the efficiency of heterogeneous nucleation and reduces free energy of growth. Moreover, in BEI images, it is found that precipitation of white-spot particles and the result of the EDS analysis revealed that T-ZrO2 formed because of the solid dissolution of Ca and Mg in Zr lead ZrO2 to change from M phase into T phase. The dielectric constant is basically below 10 within low dielectric constant range and Qxf of Diopside phase with crystal growth relatively increases higher. ZrO2 added in 5.05 mol% shows better performance of Qxf is 7310 GHz.
In the second part of this study, in order to make glass-ceramic material system of Diopside phase to be applied in co-firing the electrode of base metal in the process of LTCC. Different sintering atmospheres are applied to affect the addition of 5.05 mol% ZrO2 in Diopside phase and to contrast the different sintering results in general atmosphere and Nitrogen. In the part of electricity, the value of Qxf in the condition of Nitrogen sintering apparently reduces into 3330 GHz. In the analysis of XRD, it is found that the peak value of specimen in the condition of Nitrogen sintering widens because many gaps form inside the crystal of the specimen that cause the larger strain value in the crystal. In addition, in the analysis of XPS, it is proved that there is an obvious tendency of restoration in Diopside phase; thus, glass ceramic after heat treatment in the atmosphere of hypoxia Nitrogen causes the phenomenon of restoration to make the material become the state of Semiconductor and affect the electrical properties.
In the third part, in order to improve the sintering characteristic in Nitrogen, the addition of ZnO is used as reductive-resistance agent to analyze changes of ZnO in Diopside phase according to different ratios. By means of XRD, it is found that as the addition of ZnO ranges between 0.5 and 4mol%, Diopside phase and T-ZrO2 are basically maintained. And R-Zn2SiO4 forms after 6 and 8 mol%, but these phases belong show lower dielectric constant; therefore, dielectric constant still maintains between 7 and 8. In the condition of 3.31mol%, cell volume starts to have the tendency of increasing expansion and it is speculated that the large amount of Zn occupies the place of Si because the radius of Zn ion is larger than that of Si to cause the distortion of phase crystal. The tendency of crystal expansion and the increase of Qxf are consistent. In the analysis of XPS, it is verified that as ZnO increases in 3.31~8mol%, bonding energies of Diopside phase deviate toward high bonding energy (eV). It is also proved that distortion of crystal makes Oxygen difficult to separate and causes the effect of reductive-resistance. The addition of ZnO exactly helps improve the property of Qxf in Nitorgen. The addition of ZnO in 4mol% shows the best electrical properties. Dielectric constant is 7.25 and Qxf is 8330.

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