TWI403486B - Dielectric ceramic composition - Google Patents
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- TWI403486B TWI403486B TW99120459A TW99120459A TWI403486B TW I403486 B TWI403486 B TW I403486B TW 99120459 A TW99120459 A TW 99120459A TW 99120459 A TW99120459 A TW 99120459A TW I403486 B TWI403486 B TW I403486B
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本發明是有關於一種介電陶瓷組成物，且特別是有關於一種具有高介電常數的介電陶瓷組成物。 This invention relates to a dielectric ceramic composition, and more particularly to a dielectric ceramic composition having a high dielectric constant.
隨著無線通訊技術的進步，可攜式行動通訊產品的需求也大量增加，並朝向輕薄短小、高可靠度與低價化發展，以達小型化及輕量化的高密度構裝要求。由於無線通訊產品是藉由微波傳遞訊號，其中所使用的陶瓷材料，必須能在室溫下具有高介電常數值(dielectric constant，ε r)以及高的品質因子(quality factor，Q×f)。 With the advancement of wireless communication technology, the demand for portable mobile communication products has also increased greatly, and the development has become shallow, short, high-reliability and low-cost, in order to achieve high-density construction requirements of miniaturization and light weight. Since wireless communication products transmit signals by microwave, the ceramic materials used must have a high dielectric constant (ε r) and a high quality factor (Q × f) at room temperature. .
在中華民國專利公告號第373201號中，揭露了一種介電陶瓷組合物，包含(BaCa)TiO3作為主要成份，而碳酸錳(MnCO3)、三氧化二鏑(Dy2O3)、五氧化二鈮(Nb2O5)則作為副成份。雖然此介電陶瓷組合物可達到介電常數10000以上，但僅能在低氧分壓情況下進行燒結，無法在一般氧化氣氛下燒結，難以在工業上應用。 In the Republic of China Patent Publication No. 373201, a dielectric ceramic composition comprising (BaCa)TiO 3 as a main component, and manganese carbonate (MnCO 3 ), antimony trioxide (Dy 2 O 3 ), and five is disclosed. Niobium oxide (Nb 2 O 5 ) is used as an accessory component. Although the dielectric ceramic composition can achieve a dielectric constant of 10,000 or more, it can be sintered only under a low oxygen partial pressure, and cannot be sintered in a general oxidizing atmosphere, and it is difficult to apply it industrially.
在中華民國專利公告號第372948號中，揭露了一種介電陶瓷組合物，包含鈦酸鋇(BaTiO3)、鋯酸鋇(BaZrO3)、鈦酸鈣(CaTiO3)、鈦酸鎂(MgTiO3)作為主要成份，而以氧化鎳(NiO)、二氧化鈰(CeO2)、二氧化錳(MnO2)與二氧化矽(SiO2)作為副成份。然而此介電陶瓷組合物僅能達到介電常數介於4000~6000之間。 In the Republic of China Patent Publication No. 372948, a dielectric ceramic composition comprising BaTiO 3 , BaZrO 3 , calcium titanate (CaTiO 3 ), magnesium titanate (MgTiO) is disclosed. 3 ) As a main component, nickel oxide (NiO), cerium oxide (CeO 2 ), manganese dioxide (MnO 2 ) and cerium oxide (SiO 2 ) are used as auxiliary components. However, the dielectric ceramic composition can only achieve a dielectric constant between 4000 and 6000.
在中華民國專利公告號第476733號中，揭露一種具有 極高介電率之多重摻雜鈦酸鋇，包含[(BaSr)La][TiMg]O3作為主要成份，進行燒結後，可在攝氏70℃時達到高於20000的介電常數。然而，此組合物介電峰值的溫度點無法降低至室溫範圍就難以在工業上應用。 In the Republic of China Patent No. 476733, a multi-doped barium titanate having a very high dielectric constant is disclosed, which comprises [(BaSr)La][TiMg]O 3 as a main component, and after sintering, it can be in Celsius. A dielectric constant higher than 20,000 is achieved at 70 °C. However, the temperature point at which the dielectric peak of the composition cannot be lowered to the room temperature range is difficult to apply industrially.
在工業上生產圓盤式介電陶瓷安規電容係利用隧道連續式燒結爐進行燒結，燒結爐內的溫度穩定區間不大，一般在攝氏正負十度的範圍之間就算很好。但是陶瓷電容有一特性，介電常數會隨燒結溫度的升高而增大，燒結溫度越高，介電常數越高。因此燒結爐內的因在不同的溫度區間的溫度差異，會造成介電陶瓷組成物的介電常數有不均勻的情況，因此其電容值在量產時變異過大問題而造成可靠率不佳的問題。 The industrial production of disc-type dielectric ceramic safety capacitors is performed by tunnel continuous sintering furnace. The temperature stability range in the sintering furnace is not large, and it is generally good between plus or minus ten degrees Celsius. However, ceramic capacitors have a characteristic that the dielectric constant increases as the sintering temperature increases. The higher the sintering temperature, the higher the dielectric constant. Therefore, the difference in temperature between the different temperature ranges in the sintering furnace may cause the dielectric constant of the dielectric ceramic composition to be uneven. Therefore, the capacitance value is too large in the mass production to cause a problem of poor reliability. problem.
因此，需要一種能具有均勻介電常數且在室溫下的介電峰值高於9000的介電陶瓷組成物。 Therefore, there is a need for a dielectric ceramic composition that has a uniform dielectric constant and a dielectric peak at room temperature above 9000.
因此，本發明之一目的就是在提供一種介電陶瓷組成物，控制主成份與副成份的添加比例，降低介電常數隨燒結溫度升高的敏感度，可顯著改善燒結溫度造成介電常數變異量過大問題。 Therefore, an object of the present invention is to provide a dielectric ceramic composition which controls the addition ratio of the main component and the subcomponent, reduces the sensitivity of the dielectric constant with the increase of the sintering temperature, and can significantly improve the dielectric constant variation caused by the sintering temperature. The amount is too big.
依據本發明一實施例，提供一種介電陶瓷組合物，包含鈦酸鋇(BaTiO3)、鋯酸鋇(BaZrO3)、鈦酸鍶(SrTiO3)、鈦酸鈣(CaTiO3)、鋯酸鈣(CaZrO3以及一燒結添加劑。其中以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100重量份為基準，燒結添加劑具有0.32~4.5重量份。燒結添 加劑包含五氧化二鈮(Nb2O5)、三氧化二鉍(Bi2O3)、二氧化錳(MnO2)、二氧化矽(SiO2)以及三氧化二釔(Y2O3)。其中介電陶瓷組成物進行燒結後之介電常數範圍介於9000~11000。 According to an embodiment of the present invention, a dielectric ceramic composition comprising BaTiO 3 , BaZrO 3 , SrTiO 3 , calcium titanate (CaTiO 3 ), zirconate is provided. Calcium (CaZrO 3 and a sintering additive), wherein the sintering additive has a content of 0.32 to 4.5 parts by weight based on 100 parts by weight of the total of barium titanate, barium zirconate, barium titanate, calcium titanate and calcium zirconate. Bismuth pentoxide (Nb 2 O 5 ), bismuth trioxide (Bi 2 O 3 ), manganese dioxide (MnO 2 ), cerium oxide (SiO 2 ), and antimony trioxide (Y 2 O 3 ). The dielectric constant of the dielectric ceramic composition after sintering is in the range of 9000 to 11,000.
依據本發明一實施例，提供一種介電陶瓷組成物，以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100莫耳份為基準，鈦酸鋇佔80~90莫耳%、鋯酸鋇佔3~9莫耳%之、鈦酸鍶佔1~5莫耳%、鈦酸鈣佔3~10莫耳%以及鋯酸鈣佔2~8莫耳%。 According to an embodiment of the present invention, a dielectric ceramic composition is provided, which is based on a total of 100 moles of barium titanate, barium zirconate, barium titanate, calcium titanate, and calcium zirconate, and barium titanate accounts for 80~. 90% Mo, zirconate yttrium accounts for 3 to 9 mol%, barium titanate accounts for 1 to 5 mol%, calcium titanate accounts for 3 to 10 mol%, and calcium zirconate accounts for 2 to 8 mol%.
依據本發明另一實施例，提供一種介電陶瓷組成物，以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100重量份為基準，燒結添加劑包含0.01~0.8重量份之五氧化二鈮、0.2~1.2重量份之三氧化二鉍、0.01~0.5重量份之二氧化錳、0.01~1.00重量份之二氧化矽以及0.1~1.00重量份之三氧化二釔。 According to another embodiment of the present invention, a dielectric ceramic composition is provided, which comprises 0.01 to 0.8 of a sintering additive based on 100 parts by weight of barium titanate, barium zirconate, barium titanate, calcium titanate, and calcium zirconate. Parts by weight of antimony pentoxide, 0.2 to 1.2 parts by weight of antimony trioxide, 0.01 to 0.5 part by weight of manganese dioxide, 0.01 to 1.00 part by weight of cerium oxide, and 0.1 to 1.00 part by weight of antimony trioxide.
依據本發明另一實施例，提供一種介電陶瓷組成物，於一溫度範圍介於1290℃~1330℃之間進行燒結後，該介電陶瓷組成物之介電變異量介於-200~200之間。 According to another embodiment of the present invention, there is provided a dielectric ceramic composition, wherein a dielectric variation of the dielectric ceramic composition is between -200 and 200 after sintering at a temperature ranging from 1290 ° C to 1330 ° C. between.
本發明之介電陶瓷組成物的優點在於透過調整組成份與燒結添加劑的比例，改善因燒結溫度造成變異過大的問題並達到介電常數範圍介於9000~11000，以克服因製程設備造成的低良率問題。 The dielectric ceramic composition of the present invention has the advantages of improving the problem of excessive variability due to sintering temperature by adjusting the ratio of the composition component to the sintering additive and achieving a dielectric constant ranging from 9000 to 11000 to overcome the low temperature caused by the process equipment. Yield problem.
本發明之介電陶瓷組合物的一態樣，係包含鈦酸鋇、 鋯酸鋇、鈦酸鍶、鈦酸鈣、鋯酸鈣以及一燒結添加劑。燒結添加劑包含五氧化二鈮、三氧化二鉍、二氧化錳、二氧化矽以及三氧化二釔。其中此種電陶瓷組成物進行燒結後，可達到介電常數介於9000~11000。 An aspect of the dielectric ceramic composition of the present invention comprises barium titanate, Barium zirconate, barium titanate, calcium titanate, calcium zirconate and a sintering additive. The sintering additive comprises antimony pentoxide, antimony trioxide, manganese dioxide, ceria, and antimony trioxide. After the electroceramic composition is sintered, the dielectric constant can reach 9000~11000.
在一實施例中，以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100莫耳份，鈦酸鋇佔80~90莫耳%、鋯酸鋇佔3~9莫耳%、鈦酸鍶佔1~5莫耳%、鈦酸鈣佔3~10莫耳%以及鋯酸鈣佔2~8莫耳%。 In one embodiment, the total amount of barium titanate, barium zirconate, barium titanate, calcium titanate, and calcium zirconate is 100 moles, barium titanate accounts for 80 to 90 mole%, and barium zirconate accounts for 3~. 9 mol%, barium titanate accounts for 1 to 5 mol%, calcium titanate accounts for 3 to 10 mol%, and calcium zirconate accounts for 2 to 8 mol%.
在一實施例中，以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100重量份為基準，此燒結添加劑具有0.32~4.5重量份。 In one embodiment, the sintering additive has a content of 0.32 to 4.5 parts by weight based on 100 parts by weight of the total of barium titanate, strontium zirconate, barium titanate, calcium titanate, and calcium zirconate.
在另一實施例中，以鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣合計為100重量份為基準，燒結添加劑包含0.01~0.8重量份之五氧化二鈮、0.2~1.2重量份之三氧化二鉍、0.01~0.5重量份之二氧化錳、0.01~1.00重量份之二氧化矽以及0.1~1.00重量份之三氧化二釔。 In another embodiment, the sintering additive comprises 0.01 to 0.8 parts by weight of bismuth pentoxide, 0.2 based on 100 parts by weight of total of barium titanate, strontium zirconate, barium titanate, calcium titanate, and calcium zirconate. ~1.2 parts by weight of antimony trioxide, 0.01 to 0.5 part by weight of manganese dioxide, 0.01 to 1.00 part by weight of cerium oxide, and 0.1 to 1.00 part by weight of antimony trioxide.
以下則以實際實施例更具體地說明本發明，惟本發明的範圍不受這些實施例限制。 The present invention will be more specifically described by the following examples, but the scope of the invention is not limited by the examples.
首先，預先製備包含鈦酸鋇、鋯酸鋇、鈦酸鍶、鈦酸鈣以及鋯酸鈣的主要成份。準備81莫耳份之鈦酸鋇、7莫耳份鋯酸鋇、4莫耳份之鈦酸鍶、5莫耳份之鈦酸鈣以及3莫耳份之鋯酸鈣。接著將上述材料置入Nylon 6之球磨桶中，在此球磨桶中加入瑪瑙球進行球磨混合12小時。將球磨混合後之漿液經過濾及烘乾。接著在1200℃下進行鍛燒保持溫度兩小時，以製備介電陶瓷組合物之起始材料。 First, a main component comprising barium titanate, barium zirconate, barium titanate, calcium titanate, and calcium zirconate is prepared in advance. 81 moles of barium titanate, 7 moles of barium zirconate, 4 moles of barium titanate, 5 moles of calcium titanate, and 3 moles of calcium zirconate were prepared. The above materials were then placed in a Nylon 6 ball mill barrel, and an agate ball was placed in the ball mill barrel for ball milling for 12 hours. The slurry after mixing the ball mill is filtered and dried. The calcination was then carried out at 1200 ° C for two hours to prepare a starting material for the dielectric ceramic composition.
在以下實施例與比較實施例中，除另外指定，最後燒結溫度為1290℃~1330℃。 In the following examples and comparative examples, the final sintering temperature was 1290 ° C to 1330 ° C unless otherwise specified.
主要成份：總重為100重量份之前述介電陶瓷組合物之起始材料。 Main component: A total weight of 100 parts by weight of the starting material of the foregoing dielectric ceramic composition.
燒結添加劑：0.5重量份之三氧化二鉍、0.8重量份之五氧化二鈮以及0.3重量份之二氧化錳。 Sintering additive: 0.5 part by weight of antimony trioxide, 0.8 part by weight of antimony pentoxide, and 0.3 part by weight of manganese dioxide.
步驟：將燒結添加劑與上述介電陶瓷組合物之起始材料加入球磨桶內進行細磨，並加入釔安定氧化鋯球(Y-ZrO2)，經細磨時間八小時後使粉體達到粒徑約為1μm。接著進行烘乾後成型。進行燒結，燒結溫度介於1290℃~1330℃，燒結持續時間為兩小時。最後塗佈於陶瓷電容專用電極與電極燒附(800℃)，所測得之介電常數介於7400~8800，介電常數變異量約為1200。隨著燒結溫度的提高介電常數的變異量越趨變大，變異量最大值約為1500。 Step: adding the sintering additive and the starting material of the above dielectric ceramic composition to a ball mill barrel for fine grinding, and adding yttrium zirconia balls (Y-ZrO 2 ), and the powder is granulated after eight hours of fine grinding time. The diameter is about 1 μm. It is then dried and molded. Sintering is carried out, the sintering temperature is between 1290 ° C and 1330 ° C, and the sintering duration is two hours. Finally, it is applied to the ceramic capacitor electrode and the electrode is baked (800 ° C). The measured dielectric constant is between 7400 and 8800, and the dielectric constant variation is about 1200. As the sintering temperature increases, the variation of the dielectric constant becomes larger, and the maximum amount of variation is about 1500.
主要成份：總重為100重量份之前述介電陶瓷組合物之起始材料。 Main component: A total weight of 100 parts by weight of the starting material of the foregoing dielectric ceramic composition.
燒結添加劑：0.5重量份之三氧化二鉍、0.8重量份之五氧化二鈮、0.3重量份之二氧化錳以及0.4重量份之二氧化錫(SnO2)。 Sintering additive: 0.5 parts by weight of antimony trioxide, 0.8 parts by weight of antimony pentoxide, 0.3 parts by weight of manganese dioxide, and 0.4 parts by weight of tin dioxide (SnO 2 ).
步驟：比較實施例1之實驗操作與比較實施例1相同，其差異處僅在於比較實施例2所使用之燒結添加劑更包含二氧化錫。最後塗佈於陶瓷電容專用電極與電極燒附(800℃)，所測得之介電常數介於4000~8000。隨著燒結溫度的 提高介電常數的變異量越趨變大，變異量最大值約4000。 Step: The experimental operation of Comparative Example 1 was the same as that of Comparative Example 1, except that the sintering additive used in Comparative Example 2 further contained tin dioxide. Finally, it is applied to the dedicated electrode of the ceramic capacitor and the electrode is baked (800 ° C), and the measured dielectric constant is between 4000 and 8000. With sintering temperature Increasing the variation of the dielectric constant becomes larger and larger, and the maximum amount of variation is about 4,000.
主要成份：總重為100重量份之前述介電陶瓷組合物之起始材料。 Main component: A total weight of 100 parts by weight of the starting material of the foregoing dielectric ceramic composition.
燒結添加劑：0.2重量份之五氧化二鈮、1.0重量份之三氧化二鉍、0.4重量份之二氧化錳、0.8重量份之二氧化矽以及0.2重量份之三氧化二釔。 Sintering additive: 0.2 part by weight of antimony pentoxide, 1.0 part by weight of antimony trioxide, 0.4 part by weight of manganese dioxide, 0.8 part by weight of cerium oxide, and 0.2 part by weight of antimony trioxide.
步驟：實施例1之實驗操作與比較實施例1相同，其差異處僅在於比較實施例2所使用之燒結添加劑更包含二氧化矽與三氧化二釔。最後塗佈於陶瓷電容專用電極與電極燒附(800℃)，所測得之介電常數介於9400~9600之間。隨著燒結溫度的提高介電常數的變異量並未有太大的改變，變異量最大值約為200。 Step: The experimental operation of Example 1 was the same as that of Comparative Example 1, except that the sintering additive used in Comparative Example 2 further contained ceria and antimony trioxide. Finally, it is applied to the ceramic capacitor electrode and the electrode is baked (800 ° C), and the measured dielectric constant is between 9400 and 9600. As the sintering temperature increases, the variation of the dielectric constant does not change much, and the maximum amount of variation is about 200.
由此可見，本發明之實施例之介電陶瓷組成物透過調整組成份與燒結添加劑的比例，達到介電常數範圍介於9000~11000，且在燒結溫度正負20℃的範圍內達到變異量介於-200~200。 It can be seen that the dielectric ceramic composition of the embodiment of the present invention achieves a dielectric constant ranging from 9000 to 11000 by adjusting the ratio of the composition component to the sintering additive, and reaches a variation in the range of positive and negative sintering temperatures of 20 ° C. At -200~200.
雖然本發明已以實施方式揭露如上，然其並非用以限定本發明，任何熟習此技藝者，在不脫離本發明之精神和範圍內，當可作各種之更動與潤飾，因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。 Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.
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| TW476733B (en) * | 1999-09-30 | 2002-02-21 | Dong-Hau Kuo | Barium titanate ceramics with extremely high dielectric constants |
| TW200846299A (en) * | 2007-03-29 | 2008-12-01 | Tdk Corp | Production method of dielectric ceramic composition and production method of electronic device |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW476733B (en) * | 1999-09-30 | 2002-02-21 | Dong-Hau Kuo | Barium titanate ceramics with extremely high dielectric constants |
| TW200846299A (en) * | 2007-03-29 | 2008-12-01 | Tdk Corp | Production method of dielectric ceramic composition and production method of electronic device |
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| TW201200490A (en) | 2012-01-01 |
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