TWI442984B - Copper powder for conductive paste and conductive paste - Google Patents

Copper powder for conductive paste and conductive paste Download PDF

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TWI442984B
TWI442984B TW097150817A TW97150817A TWI442984B TW I442984 B TWI442984 B TW I442984B TW 097150817 A TW097150817 A TW 097150817A TW 97150817 A TW97150817 A TW 97150817A TW I442984 B TWI442984 B TW I442984B
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copper powder
conductive paste
atm
copper
particles
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TW097150817A
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TW200940213A (en
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Koyu Ota
Toru Kurimoto
Yoshiaki Uwazumi
Koichi Miyake
Katsuhiko Yoshimaru
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Mitsui Mining & Smelting Co
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • C22C9/10—Alloys based on copper with silicon as the next major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0425—Copper-based alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20—Conductive material dispersed in non-conductive organic material
    • H01B1/22—Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G4/00—Fixed capacitors; Processes of their manufacture
    • H01G4/002—Details
    • H01G4/005—Electrodes
    • H01G4/008—Selection of materials

Description

導電性糊膏用銅粉及導電性糊膏Copper powder and conductive paste for conductive paste

本發明是有關導電性糊膏用銅粉及使用此銅粉之導電性糊膏，尤其是有關，經由網篩印刷加成(additive)法之形成導體電路用或積層陶瓷電容器之外部電極用等之各種電接點構件用之導電性糊膏的導電材料等所適用的銅粉，及使用此銅粉之導電性糊膏。The present invention relates to a copper powder for a conductive paste and a conductive paste using the copper powder, and more particularly to an external electrode for forming a conductor circuit or a laminated ceramic capacitor by a screen printing additive method. A copper powder suitable for a conductive material such as a conductive paste for various electrical contact members, and a conductive paste using the copper powder.

銅粉，由其之處理容易性之觀點而言，經由網版印刷追加(additive)法，作為形成導體電路，或積層陶瓷電容器之外部電極等之各種電接點式構件，所使用之導電性糊膏的導電材料等，一直以來都廣泛利用銅粉。From the viewpoint of easiness of handling, the copper powder is used as a conductive method for forming various types of electrical contact members such as a conductor circuit or an external electrode of a multilayer ceramic capacitor. Copper powder has been widely used as a conductive material for pastes.

上述導電性糊膏，例如，可藉由在銅粉中摻配環氧樹脂等之樹脂及此之硬化劑等之各種添加劑經過捏合(kneading)而得。此時所使用之銅粉，可以藉由自含有銅鹽之溶液等經還原劑而析出之濕式還原法、或使銅鹽經加熱氣化而在氣相中還原之氣相還原法、或以惰性氣體或水等冷媒急速冷卻熔融之銅錠(copper ingots)的粉末噴霧(Atomization)法等方法來製造。The conductive paste can be obtained, for example, by kneading a copper powder in which a resin such as an epoxy resin or the like and a curing agent such as a hardener are blended. The copper powder used at this time may be a vapor reduction method in which a copper salt is precipitated by a reducing agent such as a solution containing a copper salt, or a vapor phase reduction method in which a copper salt is heated and vaporized to be reduced in a gas phase, or It is produced by a method such as a powder atomization method in which a copper ingot is rapidly cooled by a refrigerant such as an inert gas or water.

在上述之銅粉製造方法中，噴霧法與一般廣泛利用之濕式還原法相比，係具有下列優點：可減少所得銅粉中之不純物的殘留濃度；以及可減少所得銅粉粒子之表面至內部的細孔。因此，藉由噴霧法製造之銅粉，在導電性糊膏之導電材料中使用時，即有可減少糊膏硬化時之氣體的產生量，且可大幅抑制氧化進行之優點。In the above copper powder production method, the spray method has the following advantages as compared with the generally widely used wet reduction method: it can reduce the residual concentration of impurities in the obtained copper powder; and can reduce the surface of the obtained copper powder particles to the inside. The pores. Therefore, when the copper powder produced by the spray method is used in the conductive material of the conductive paste, the amount of gas generated when the paste is cured can be reduced, and the advantage of oxidation can be greatly suppressed.

然而銅粉，因為其之導電性高，雖適於作為導電性糊膏之導電材料，但隨著粒度之微細化，連帶地，在耐氧化性方面會變差，為了改善此等缺點而有採用在粒子表面塗佈有耐氧化性之銀(專利文獻1)，以無機氧化物塗佈(專利文獻2)等之方法。However, copper powder is suitable as a conductive material for a conductive paste because of its high conductivity. However, as the particle size is finer, it is inferior in oxidation resistance, and in order to improve these defects, Silver which is coated with oxidation resistance on the surface of the particles (Patent Document 1) is coated with an inorganic oxide (Patent Document 2).

[專利文獻1]日本特開平10-152630號公報[Patent Document 1] Japanese Patent Laid-Open No. Hei 10-152630

[專利文獻2]日本特開2005-129424號公報[Patent Document 2] Japanese Patent Laid-Open Publication No. 2005-129424

一直以來，由導電性糊膏等來形成電路之際，總是要求更微細化，因此必然地在導電性糊膏中所使用之導電粉的粒度也要求微細化。在與此同時，除了確保糊膏特性之安定性、可信性之外，還需要求形狀及粒度之均勻度，並且需要不損及導電性。因此僅要求耐氧化性之改善，只能以專利文獻1至2等之技術對應。Conventionally, when a circuit is formed of a conductive paste or the like, it is always required to be finer. Therefore, the particle size of the conductive powder used in the conductive paste is inevitably required to be fine. At the same time, in addition to ensuring the stability and credibility of the paste characteristics, the uniformity of the shape and the particle size is required, and it is necessary to not impair the conductivity. Therefore, only improvement of oxidation resistance is required, and it is only possible to correspond to the techniques of Patent Documents 1 to 2.

然而，在專利文獻1至2等之技術中，由於依賴著被覆技術，因此不僅需要很多會損及銅以卟的導電性成分，同時也會產生銅粉粒子自芯材剝離之問題。同時，即使減少形狀或粒子之不均，也期望構成之粒子均一，並且為含低氧濃度，但目前相關之銅粉尚未發現可以滿足期望者。However, in the techniques of Patent Documents 1 to 2 and the like, since the coating technique is relied on, not only a large amount of the conductive component which may damage the copper but also the problem that the copper powder particles are peeled off from the core material is required. At the same time, even if the shape or the unevenness of the particles is reduced, it is desirable that the constituent particles are uniform and contain a low oxygen concentration, but the related copper powder has not been found to satisfy the expectation.

本發明之目的是提供導電性糊膏用銅粉及導電性糊膏，其中該導電性糊膏用銅粉係粒度微細且同時無損及耐氧化性、導電性之平衡的銅粉，尤其，銅粉之形狀及粒度少有不均並含有低氧濃度。An object of the present invention is to provide a copper powder for a conductive paste and a conductive paste, wherein the copper powder for the conductive paste is copper powder having a fine particle size and at the same time not deteriorating and having a balance between oxidation resistance and conductivity, in particular, copper. The shape and particle size of the powder are less uneven and contain a low oxygen concentration.

本發明人等為了解決上述課題，經過專心研究之結果，發現：在銅粉之粒子內部，使含有特定量之Si時，就能解決上述課題，遂而完成本發明。In order to solve the above problems, the inventors of the present invention have found that the above problems can be solved by including a specific amount of Si in the particles of the copper powder, and the present invention has been completed.

亦即，本發明之導電性糊膏用銅粉，其特徵係：粒子內部之Si(矽)含量為0.1atm %至10atm %。That is, the copper powder for conductive paste of the present invention is characterized in that the content of Si (矽) in the particles is from 0.1 atm% to 10 atm%.

進一步，在粒子內部之P(磷)含量可為0.01atm %至0.3atm %，而Si/P(atm比)以在4至200為佳。Further, the P (phosphorus) content inside the particles may be from 0.01 atm% to 0.3 atm%, and the Si/P (atm ratio) is preferably from 4 to 200.

同時，粒子內部之Ag(銀)含量可為0.1atm %至10atm %。Meanwhile, the content of Ag (silver) inside the particles may be from 0.1 atm% to 10 atm%.

因此，係以藉由噴霧(Atomization)法而製造者為佳。Therefore, it is preferable to manufacture by the atomization method.

同時，在240℃及600℃之重量變化率(Tg(%))/比表面積(SSA)之差以在1%/m2 /cm3 至30%/m2 /cm3 為佳。Meanwhile, the difference in weight change rate (Tg (%)) / specific surface area (SSA) at 240 ° C and 600 ° C is preferably from 1% / m 2 /cm 3 to 30% / m 2 / cm 3 .

本發明之其他態樣，係含有上述導電性糊膏用銅粉之導電性糊膏。Another aspect of the present invention is a conductive paste containing the copper powder for a conductive paste.

本發明之導電性糊膏用銅粉，不但粒度微細且耐氧化性優異，並且可取得導電性之平衡。進一步，銅粉之形狀及粒度少有不均，且含氧濃度低，故可適用在藉由網版印刷加成法而形成導體電路用途或積層陶瓷電容器之外部電極用等之各種電接點構材用途之導電性糊膏的導電材料等。The copper powder for conductive paste of the present invention is excellent in not only a fine particle size but also excellent in oxidation resistance, and a balance of conductivity can be obtained. Further, since the shape and particle size of the copper powder are less uneven and the oxygen concentration is low, it is applicable to various electrical contacts for forming a conductor circuit or an external electrode for a multilayer ceramic capacitor by a screen printing addition method. A conductive material such as a conductive paste for structural use.

發明實施之最佳形態：The best form of invention implementation:

藉由導電性糊膏用銅粉之實施形態來說明本發明，但本發明不侷限於以下之實施形態。The present invention will be described by way of an embodiment of a copper powder for conductive paste, but the present invention is not limited to the following embodiments.

本發明之導電性糊膏用銅粉，其特徵為：粒子內部中之Si(矽)含量為0.1atm %至10atm %。The copper powder for conductive paste of the present invention is characterized in that the content of Si (矽) in the interior of the particles is from 0.1 atm% to 10 atm%.

此處之重點並非僅含有Si者，而是在粒子內部中含有特定之量者。The focus here is not only on the Si, but on the inside of the particle.

亦即，上述專利文獻中所代表的，在以往技術中大多揭示SiO2 等各種化合物被覆或附著在芯材的銅粉粒子表面之銅粉，雖具有改善耐氧化性之效果，但得不到本申請案所尋求之，除了粒度微細，耐氧化性之外，亦無損及導電性平衡之銅粉。In other words, in the prior art, in the prior art, copper powder coated with various compounds such as SiO 2 or adhered to the surface of the copper powder particles of the core material is often disclosed, and the effect of improving oxidation resistance is not obtained. The copper powder which is sought for in this application, in addition to fine particle size and oxidation resistance, is also non-destructive and conductive.

同時，本發明之導電性糊膏用銅粉中所含之Si成分，係在粒子內部之金屬相中以平均分布為佳，推測係作成合金成分而存在粒子內部者。At the same time, the Si component contained in the copper powder for conductive paste of the present invention is preferably distributed evenly in the metal phase inside the particles, and it is presumed that it is formed as an alloy component and is present inside the particles.

同時，Si之含量為0.1atm %至10atm %，以0.5atm %至5atm %為佳，以0.5atm %至3atm %為更佳。此含量不足0.1atm %時，不能期待有本發明所訴求之效果。同時，超過10atm %之時，不僅損及導電性，也得不到添加所應見到之效果。Meanwhile, the content of Si is from 0.1 atm % to 10 atm %, preferably from 0.5 atm % to 5 atm %, more preferably from 0.5 atm % to 3 atm %. When the content is less than 0.1 atm%, the effect of the present invention cannot be expected. At the same time, when it exceeds 10 atm%, not only the conductivity is impaired, but also the effect that it should be seen is not obtained.

同時本發明之導電性糊膏用銅粉，除了Si之外，在粒子內部中之P(磷)含量以0.01atm %至0.3atm %為佳，更佳為0.02atm %至0.1atm %。Si與P在銅粉中共存，若在如此之特定量範圍內，則不但粒度微細、具耐氧化性，且亦不損及導電性，更且形狀或粒度少有不均，而提高含低氧濃度。Meanwhile, the copper powder for conductive paste of the present invention preferably has a P (phosphorus) content in the interior of the particles of from 0.01 atm % to 0.3 atm %, more preferably from 0.02 atm % to 0.1 atm %, in addition to Si. Si and P coexist in the copper powder. If it is within such a specific amount range, not only the particle size is fine, it is resistant to oxidation, and the conductivity is not impaired, and the shape or particle size is less uneven, and the content is low. Oxygen concentration.

同時，本發明之導電性糊膏用銅粉，Si/P(a t m比)以4至200為佳，更佳為10至100。Si/P之比在如此之範圍時，容易取得粒度微細、耐氧化性、高導電性、形狀或粒度少有不均、含低氧濃度等特徵的平衡。Meanwhile, the copper powder for conductive paste of the present invention preferably has a Si/P (a t m ratio) of 4 to 200, more preferably 10 to 100. When the ratio of Si/P is in such a range, it is easy to obtain a balance of fine particle size, oxidation resistance, high conductivity, small unevenness in shape or particle size, and low oxygen concentration.

同時，本發明之導電性糊膏用銅粉，粒子內部中之Ag(銀)含量以0.1atm %至10atm %為佳，更佳為0.3atm %至5atm %，最佳是在0.5atm %至3atm %。若在如此之特定範圍內時，可以維持導電性糊膏用銅粉之原有的耐氧化，可以更提高導電性，並且也可以抑制成本。Meanwhile, in the copper paste for conductive paste of the present invention, the content of Ag (silver) in the interior of the particles is preferably from 0.1 atm % to 10 atm %, more preferably from 0.3 atm % to 5 atm %, most preferably from 0.5 atm % to 3atm %. When it is within such a specific range, the original oxidation resistance of the copper powder for conductive paste can be maintained, the conductivity can be further improved, and the cost can be suppressed.

因此，在含有Si、Ag及P之任一者時，除了粒度微細且形狀及粒度少有不均，並有飛躍的優異耐氧化性之外，可成為有更優異導電性之導電性糊膏用銅粉。Therefore, when any of Si, Ag, and P is contained, it is a conductive paste having more excellent conductivity, in addition to fine particle size, uneven shape and particle size, and excellent oxidation resistance of leap. Use copper powder.

同時，本發明之導電性糊膏用銅粉，即使為以濕式還原法所得者，雖亦可期待有相符之效果，但如顧及到粒子形狀均勻整齊，且在作為導電性糊膏使用之際少有氣體產生等之優點時，還是以噴霧法製造者為佳。Meanwhile, the copper powder for a conductive paste of the present invention can be expected to have a satisfactory effect even if it is obtained by a wet reduction method, but it is used as a conductive paste, taking into consideration that the shape of the particles is uniform and uniform. When there are few advantages such as gas generation, it is better to use a spray method.

關於噴霧法，雖有氣體噴霧法與水噴霧法，如企圖使粒子形狀均整化，則以選擇氣體噴霧法為佳，如企圖使粒子微細化，則以選擇水噴霧法為佳。同時，在噴霧法之內，以藉由高壓噴霧法製造者為佳。藉由如此之高壓噴霧法所得之銅粉，粒子較均整，或更為微細，故而較佳。另外，高壓噴霧法係指，在水噴霧法中，以50MPa至150MPa左右之水壓力進行噴霧之方法，在氣體噴霧法中，係以1.5MPa至3MPa左右之氣體壓力進行噴霧之方法。Regarding the spray method, although there is a gas spray method and a water spray method, it is preferable to select a gas spray method in order to make the shape of the particles uniform, and it is preferable to select a water spray method in order to make the particles fine. At the same time, it is preferred to be manufactured by a high pressure spray method within the spray method. The copper powder obtained by such a high-pressure spray method is preferable because the particles are relatively uniform or finer. Further, the high-pressure spray method is a method in which a water spray method is used to spray at a water pressure of about 50 MPa to 150 MPa, and in a gas spray method, a spray method is used at a gas pressure of about 1.5 MPa to 3 MPa.

同時，本發明之導電性糊膏用銅粉，係藉由熱重量/差示熱分析(differential thermal analysis)裝置，於240℃及600℃下之重量變化率(Tg(%))/比表面積(SSA)之差(以下稱為Δ(TG/(SSA))以在1%/m2 /cm3 至30%/m2 /cm3 為佳，更佳為1%/m2 /cm3 至25%/m2 /cm3 。Meanwhile, the copper powder for conductive paste of the present invention is a weight change rate (Tg (%)) / specific surface area at 240 ° C and 600 ° C by means of a differential thermal analysis device. The difference (SSA) (hereinafter referred to as Δ(TG/(SSA)) is preferably from 1%/m 2 /cm 3 to 30%/m 2 /cm 3 , more preferably 1%/m 2 /cm 3 Up to 25%/m 2 /cm 3 .

如依此之Δ(TG/(SSA)的特性值，可以看出銅粉之耐氧化性。同時，於240℃至600℃之溫度領域中，例如，在陶瓷電容器之外部電極燒成用導電糊膏等，為使用導電糊膏之際的主要加熱溫度領域，在此領域中具有耐氧化性者極為重要。此Δ(TG/(SSA)如在上述之較佳範圍時，能充分發揮耐氧化性，也能適用在確保高導電性上。According to the characteristic value of Δ(TG/(SSA), the oxidation resistance of the copper powder can be seen. Meanwhile, in the temperature range of 240 ° C to 600 ° C, for example, the external electrode is fired for conduction in the ceramic capacitor. A paste or the like is a main heating temperature field in the case of using a conductive paste, and it is extremely important to have oxidation resistance in this field. This Δ(TG/(SSA) can fully exhibit resistance when it is in the above preferred range. Oxidation can also be applied to ensure high conductivity.

同時，本發明之導電性糊膏用銅粉，首先進一步藉由加入Ni、Al、Ti、Fe、Co、Cr、Mg、Mn、Mo、W、Ta、In、Zr、Nb、B、Ge、Sn、Zn、Bi等之中至少一種以上的元素成分，以降低融點而可提高燒結性等，而可以提高導電性糊膏所要求之各種特性之提高效果。相對於銅，此等元素的添加量，對應添加元素之種類，而由導電特性或其他之各種特性等而適當設定，惟通常為0.001質量%至2質量%左右。Meanwhile, the copper powder for conductive paste of the present invention is first added by further adding Ni, Al, Ti, Fe, Co, Cr, Mg, Mn, Mo, W, Ta, In, Zr, Nb, B, Ge, At least one or more elemental components such as Sn, Zn, and Bi can improve the sinterability and the like by lowering the melting point, and can improve the various characteristics required for the conductive paste. The amount of such elements added to the copper is appropriately set depending on the type of the additive element, the conductive property or other various characteristics, and is usually about 0.001% by mass to about 2% by mass.

同時，本發明之導電性糊膏用銅粉，其之形狀以成為粒狀者為佳，尤其以成為球狀者更佳。在此，粒狀是指長寬比(平均長徑除以平均短徑之值)具備有1至1.25左右之形狀，長寬比具備有1至1.1左右之形狀時特別稱之為球狀，同時，形狀不均之狀態，稱為不定形狀。成為如此粒狀之銅粉，相互之間的纒繞變少，使用在導電性糊膏之導電材料等之中時，在糊膏中之分散性提高，因而極佳。Meanwhile, the copper powder for conductive paste of the present invention preferably has a shape of being granulated, and is particularly preferably a spheroid. Here, the granular shape means that the aspect ratio (the average long diameter divided by the average short diameter) has a shape of about 1 to 1.25, and when the aspect ratio has a shape of about 1 to 1.1, it is particularly called a spherical shape. At the same time, the state of uneven shape is called an indefinite shape. The copper powder having such a granular shape is less likely to be entangled with each other, and when used in a conductive material such as a conductive paste, the dispersibility in the paste is improved, which is excellent.

又，本發明之導電性糊膏用銅粉，例如，可藉由雷射繞射散射式粒度分佈測定裝置等而測定，由體積累積粒徑D50 及標準偏差值SD求得變動係數(SD/D50 )為0.2至0.6時，粒度之不均分佈變少，可以提高在導電性糊膏之導電材料等使用時的糊膏中之分散性，因而極佳。Further, the copper powder for conductive paste of the present invention can be measured, for example, by a laser diffraction scattering type particle size distribution measuring apparatus, and the coefficient of variation (SD) is obtained from the volume cumulative particle diameter D 50 and the standard deviation value SD. When the ratio of /D 50 ) is from 0.2 to 0.6, the uneven distribution of the particle size is small, and the dispersibility in the paste at the time of use of the conductive material of the conductive paste or the like can be improved, which is excellent.

同時，本發明之導電性糊膏用銅粉，經由將個數平均粒徑作成0.5μm至50μm，即可成為適合成為在微細之前述導體電路形成用之導電性糊膏的導電材料等。In addition, the copper powder for a conductive paste of the present invention can be a conductive material suitable for use as a conductive paste for forming a fine conductor circuit by setting the number average particle diameter to 0.5 μm to 50 μm.

又，本發明之導電性糊膏用銅粉，由於含氧濃度成為30ppm至2500ppm，故可以確保導電性，而成為適合之導電性糊膏之導電材料等。In addition, since the copper powder for conductive paste of the present invention has an oxygen concentration of 30 ppm to 2,500 ppm, conductivity can be ensured, and it becomes a conductive material of a suitable conductive paste.

其次，說明本發明之導電性糊膏用銅粉之較佳具體的製造方法。Next, a preferred specific production method of the copper powder for conductive paste of the present invention will be described.

本發明之導電性糊膏用銅粉，係在熔融之銅中，藉由將Si成分以母合金、或化合物等之形態，添加所預定之量後，藉由所預定之噴霧法使粉體化而製造。The copper powder for conductive paste of the present invention is added to the molten copper by adding a predetermined amount to the Si component in the form of a mother alloy or a compound, and then the powder is prepared by a predetermined spraying method. Made by.

依上述製造方法，可製造粒度微細且不損及耐氧化性、及導電性之平衡之銅粉，進一步可以製造形狀或粒度少有不均且含低氧濃度之銅粉。According to the above production method, it is possible to produce a copper powder having a fine particle size without impairing the oxidation resistance and the conductivity, and further, it is possible to produce a copper powder having a small shape or a small particle size and a low oxygen concentration.

此之理由雖尚未確定，但推測是在已熔融之銅或銅合金中添加Si，為在不損害導電性之程度下，捕集生成銅粉粒子中之氧氣而可以抑制氧化者。Although the reason for this has not been determined, it is presumed that Si is added to the molten copper or copper alloy, and the oxygen in the copper powder particles can be trapped to the extent that the conductivity is not impaired, and oxidation can be suppressed.

再者，除了Si成分另添加P成分時，噴霧時之熔液表面張力可以變小，推測粒子形狀之均整化或熔液中之脫氧化，可以有效地進行者。P成分之添加，與Si成分相同，在已熔融之銅中將P成分以母合金、或化合物等之形態，添加預定之量即可。Further, when the P component is additionally added to the Si component, the surface tension of the melt at the time of spraying can be made small, and it is estimated that the uniformity of the particle shape or the deoxidation in the melt can be efficiently performed. The P component is added in the same manner as the Si component, and the P component may be added in a predetermined amount in the form of a mother alloy or a compound in the molten copper.

又，除了Si成分，藉由添加含有Ag成分，可以確保銅粉之耐氧化性，並且可以更提高導電性。Further, in addition to the Si component, by adding the Ag-containing component, the oxidation resistance of the copper powder can be ensured, and the conductivity can be further improved.

又，在上述製造方法中，由先前說明之理由，以採用高壓噴霧法較佳。但，與氣體噴霧法相比，在水噴霧法因除了銅以外之添加成分的含有收率有變低之情形，故相對於目的之銅粉中的淨值量，Si時，必需要添加1至10倍量，P時，必需要添加1至100倍量，Ag時，必需要添加1至10倍量。Further, in the above production method, it is preferable to use a high pressure spray method for the reasons described above. However, in the water spray method, the content of the additive component other than copper is lower than that of the gas spray method. Therefore, it is necessary to add 1 to 10 for the amount of Si in the copper powder for the purpose. When the amount is P, it is necessary to add 1 to 100 times. When Ag is used, it is necessary to add 1 to 10 times.

又，在上述製造方法中，噴霧之後，亦可以進行還原處理。藉由此還原處理，可以使容易進行氧化之銅粉表面的氧氣濃度更為下降。在此，上述還原處理，從作業之觀點來看，以由氣體來還原較佳。此還原處理使用之氣體，並無特別限定，但可以列舉如：氫氣、氨氣、丁烷氣體等。Further, in the above production method, the reduction treatment may be performed after the spraying. By this reduction treatment, the oxygen concentration on the surface of the copper powder which is easily oxidized can be further lowered. Here, the above reduction treatment is preferably carried out by gas reduction from the viewpoint of work. The gas used in the reduction treatment is not particularly limited, and examples thereof include hydrogen gas, ammonia gas, and butane gas.

再者，上述還原處理，係以在150℃至300℃之溫度中進行為佳，尤其是在170℃至210℃之溫度中進行更佳。查其原因，上述溫度若不足150℃時，還原速度會變緩慢，使處理效果無法充分呈現，上述溫度超過300℃時，恐怕會引起銅粉凝集或燒結，上述溫度在170℃至210℃時，由於氧氣濃度之效率可望良好地降低，故銅粉之凝集或燒結可以確實地抑制。Further, the above reduction treatment is preferably carried out at a temperature of from 150 ° C to 300 ° C, particularly preferably at a temperature of from 170 ° C to 210 ° C. If the above temperature is less than 150 ° C, the reduction rate will be slow, and the treatment effect will not be fully exhibited. When the above temperature exceeds 300 ° C, copper powder may be aggregated or sintered. The above temperature is between 170 ° C and 210 ° C. Since the efficiency of the oxygen concentration is expected to be well lowered, the aggregation or sintering of the copper powder can be surely suppressed.

又，在上述製造方法中，粉體化之後，以分級為佳。此之分級，係以目的粒度作為中心的方式，使用適當之分級裝置，可以容易將所得之銅粉分離成粗粉或微粉。在此，可望以先前說明之變動係數(SD/D50 )為0.2至0.6之方式來分級。Further, in the above production method, it is preferred to carry out classification after powdering. This classification is carried out by separating the obtained copper powder into a coarse powder or a fine powder by using a suitable classification device in a manner centering on the target particle size. Here, it is expected to be classified in such a manner that the coefficient of variation (SD/D 50 ) described earlier is 0.2 to 0.6.

在如前述之銅粉中，例如，摻配環氧樹脂等之樹脂及此之硬化劑等的各種添加劑並加以捏合等而製造含有本發明之導電性糊膏用銅粉的導電性糊膏，該銅粉之粒度微細，並可取得耐氧化性、導電性之平衡，形狀少有不均，並且因含有低氧濃度，故在藉由網版印刷加成法形成導體電路，或積層陶瓷電容器之外部電極用等之各種電接點式構件，所使用之導電性糊膏的導電材料等中，極為適用。In the copper powder as described above, for example, a conductive paste containing the copper powder for conductive paste of the present invention is produced by blending various additives such as a resin such as an epoxy resin and a curing agent thereof, and the like. The copper powder has a fine particle size, and can achieve a balance between oxidation resistance and electrical conductivity, and has a small unevenness in shape, and contains a low oxygen concentration, thereby forming a conductor circuit by a screen printing addition method, or a laminated ceramic capacitor. It is extremely suitable for use in various electrical contact members such as external electrodes, conductive materials for conductive pastes used, and the like.

其他，本發明之導電性糊膏用銅粉，也可以使用在積層陶瓷電容器之內部電極、電應感器(Inductor)或記憶裝置(Register)等之晶片組件、單板電容器電極、鉭電容器電極、樹脂多層基板、陶瓷(LTCC)多層基板、軟性印刷基板(FPC)、天線開關模組、PA模組或高頻主動濾波器(Active Filter)等之模組、PDP前面板及背面板或PDP彩色濾光器用電磁遮蔽膜、結晶型太陽電池表面電極及背面引出電極、導電性接著劑，EMI遮蔽板、RF-ID、及PC鍵盤等之膜開關、各向異性導電膜(ACF/ACP)等方面。In addition, the copper powder for conductive paste of the present invention may be used for a wafer electrode, a single-plate capacitor electrode, or a tantalum capacitor electrode of an internal electrode of a multilayer ceramic capacitor, an inductor, or a memory device. , resin multilayer substrate, ceramic (LTCC) multilayer substrate, flexible printed circuit board (FPC), antenna switch module, PA module or active filter (Active Filter) module, PDP front panel and back panel or PDP Electromagnetic shielding film for color filter, crystal solar cell surface electrode and back surface extraction electrode, conductive adhesive, EMI shielding plate, RF-ID, and PC keyboard, etc., anisotropic conductive film (ACF/ACP) etc.

以下，根據下述實施例及比較例更詳細說明本發明。Hereinafter, the present invention will be described in more detail based on the following examples and comparative examples.

(實施例1)(Example 1)

以氮氣充填氣體噴霧裝置(日新技研(股)製，NEVA-GP2型)之容器(chamber)及原料熔解室內之後，加熱熔解在熔解室內之碳坩鍋中的原料並作為熔融物[在熔解電解銅之熔液中，添加1.77g之金屬矽(日本金屬化學工業(股)製NIKSIL)，作成800g之熔液，並充分攪拌混合]。之後，將熔液自口徑∮1.5mm之噴嘴在1250℃、3.0Mpa下噴霧，得到粒子內部中含有矽之銅粉。然後，以53μm精度分析篩網(Test Sieve)篩分，在篩子下的物品當作最終之銅粉。所得之銅粉的特徵在表2中表示。After filling a chamber with a nitrogen gas filling gas spray device (manufactured by Nisshin Techno Co., Ltd., NEVA-GP2 type) and a raw material melting chamber, the raw material in the carbon crucible in the melting chamber is heated and melted as a melt [in melting] To the molten copper of electrolytic copper, 1.77 g of metal ruthenium (NIKSIL manufactured by Nippon Metal Chemical Industry Co., Ltd.) was added to prepare a melt of 800 g, and the mixture was thoroughly stirred and mixed]. Thereafter, the melt was sprayed from a nozzle having a diameter of 1.5 mm at 1,250 ° C and 3.0 MPa to obtain copper powder containing ruthenium inside the particles. Then, the sieve was tested with a precision of 53 μm, and the article under the sieve was regarded as the final copper powder. The characteristics of the obtained copper powder are shown in Table 2.

(實施例2至4)(Examples 2 to 4)

除了金屬矽之添加量變更成如表1所示者之外，其餘與實施例1同樣操作，得到銅粉。Copper powder was obtained in the same manner as in Example 1 except that the amount of addition of the metal ruthenium was changed as shown in Table 1.

(實施例5至11)(Examples 5 to 11)

除了添加金屬矽之外，另添加如表1所示之銅-磷母合金(磷品位15質量%)，其餘與實施例1同樣操作，得到銅粉。In addition to the addition of a metal ruthenium, a copper-phosphorus mother alloy (phosphorus grade: 15% by mass) as shown in Table 1 was additionally added, and the same procedure as in Example 1 was carried out to obtain a copper powder.

(實施例12至13)(Examples 12 to 13)

除了添加金屬矽或銅-磷母合金之外，另添加如表1所示之電解銀，其餘與實施例1同樣操作，得到銅粉。In addition to the addition of a metal ruthenium or a copper-phosphorus mother alloy, electrolytic silver as shown in Table 1 was additionally added, and the same operation as in Example 1 was carried out to obtain a copper powder.

(比較例1至4)(Comparative Examples 1 to 4)

除了添加如表1所示之金屬矽及/或銅-磷母合金的添加量之外，其餘與實施例1同樣操作，得到銅粉。Copper powder was obtained in the same manner as in Example 1 except that the addition amount of the metal ruthenium and/or the copper-phosphorus mother alloy shown in Table 1 was added.

關於實施例及比較例所得之銅粉，用下述之方法評估各種特性。此之結果在表2至4，以及第1至第4圖表示。With respect to the copper powder obtained in the examples and the comparative examples, various characteristics were evaluated by the following methods. The results are shown in Tables 2 to 4 and Figures 1 to 4.

(1)矽、磷含量(1) Antimony and phosphorus content

用酸溶解試料，在ICP(感應耦合電漿)中分析。The sample was dissolved in acid and analyzed in ICP (Inductively Coupled Plasma).

(2)氧氣濃度(2) Oxygen concentration

藉由氧氣‧氣氣分析裝置(堀場製作所(股)製，「EMGA-520型號」)進行分析。此之結果在表2表示。同時，為了評估經時之耐氧化性劣化，使用山陽精工製之SK-8000，以氣體流量8L/分鐘分別將各試料由10℃/分鐘昇溫至200℃為止後維持1小時，測定各試料之氧氣濃度，此之結果在表3表示。The analysis was carried out by an oxygen gas analyzer ("MEGA-520 model", manufactured by Horiba, Ltd.). The results of this are shown in Table 2. At the same time, in order to evaluate the deterioration of oxidation resistance over time, SK-8000 manufactured by Sanyo Seiko Co., Ltd. was used, and each sample was heated from 10 ° C/min to 200 ° C for 1 hour at a gas flow rate of 8 L/min, and each sample was measured. The oxygen concentration, the results of which are shown in Table 3.

(3)Δ(TG/SSA)(3) Δ(TG/SSA)

在40℃至600℃中之Tg(%)是以差示熱熱重量同時測定裝置(TG/DTA)(SII製，TG/DTA6300高溫型)(昇溫速度：10℃/分鐘、空氣流量：200mL/分鐘)測定，求取240℃至600℃之重量變化率的差。另一方面，比表面積是由以粒度測定裝置(日機裝置、Microtrac MT-3000型)測定之粒度分佈來求取，由兩者的數值以算術求得。對應溫度之實施例1至13及比較例1至4的TG/SSA示於第1圖、第2圖及第5圖。同時，實施例1至13及比較例2至4的TG/SSA除以比較例1的純銅粉的TG/SSA(圖中以[Tg(%)/SSA]Cu 記載)之結果示於第3圖、第4圖及第6圖。The Tg (%) in the range of 40 ° C to 600 ° C is a differential thermogravimetric simultaneous measuring device (TG / DTA) (manufactured by SII, TG / DTA6300 high temperature type) (temperature rising rate: 10 ° C / min, air flow rate: 200 mL) /min) Determine the difference in weight change rate from 240 ° C to 600 ° C. On the other hand, the specific surface area is obtained by a particle size distribution measured by a particle size measuring device (Nikkei apparatus, Microtrac MT-3000 type), and the numerical values of both are arithmetically determined. The TG/SSA of Examples 1 to 13 and Comparative Examples 1 to 4 corresponding to the temperatures are shown in Figs. 1, 2, and 5. Meanwhile, Examples 1 to 13 and Comparative Examples 2 to 4 TG / SSA divided copper powder of Comparative Example 1 TG / SSA (FIG to [Tg (%) / SSA] Cu described) shows the results of a third Figure, Figure 4 and Figure 6.

(4)粒子形狀(4) Particle shape

以掃描型電子顯微鏡觀察。Observed by a scanning electron microscope.

(5)D50 、SD、SD/D50 (5) D 50 , SD, SD/D 50

將試料(0.2g)投入純水(100ml)中並照射超音波(3分鐘)使分散後，藉由粒度分佈測定裝置(日機裝(股)製「Microtrac(商品名)FRA(型號)」)，分別求出體積累積粒度D50 及標準偏差值SD以及變動係數(SD/D50 )。The sample (0.2 g) was placed in pure water (100 ml) and irradiated with ultrasonic waves (3 minutes) to be dispersed. The particle size distribution measuring device (Microtrac (trade name) FRA (model) manufactured by Nikkiso Co., Ltd.) was used. ), respectively, the standard deviation value SD is obtained 50 and the coefficient of variation, and a volume cumulative particle size D (SD / D 50).

(6)粉體電阻(6) Powder resistance

將15g試料裝入筒狀容器中，以壓力機壓力40x106 Pa(408kgf/cm2 )壓縮成形而形成測定試樣，藉由電阻器Loresta AP及Loresta PD-41型(皆為三菱化學(股)製)進行測定。15 g of the sample was placed in a cylindrical container, and compression-molded at a press pressure of 40× 10 6 Pa (408 kgf/cm 2 ) to form a measurement sample, which was formed by resistors Loresta AP and Loresta PD-41 (all of which are Mitsubishi Chemical Corporation) ))).

[表2][Table 2]

如第1圖至第6圖所示，實施例之銅粉，與不含矽，或不含矽及磷之比較例相比較，可知有優異之耐氧化性，尤其在240℃至600℃之溫度領域中為優異。As shown in FIGS. 1 to 6, the copper powder of the examples has excellent oxidation resistance, especially at 240 ° C to 600 ° C, as compared with the comparative examples containing no antimony or no antimony and phosphorus. Excellent in the temperature field.

又，如表3所示，實施例之銅粉，在容易氧化之環境下長期保存時，與比較例之銅粉相比較，經時之耐氧化性有顯著的優異。Further, as shown in Table 3, when the copper powder of the example was stored for a long period of time in an environment susceptible to oxidation, the oxidation resistance over time was remarkably excellent as compared with the copper powder of the comparative example.

又，如表4所示，實施例之銅粉，與比較例之銅粉相比較，體積電阻並無多大變化，確認有良好之導電性。Further, as shown in Table 4, the copper powder of the example did not change much in volume resistance as compared with the copper powder of the comparative example, and it was confirmed that there was good conductivity.

第1圖呈示實施例及比較例之銅粉的TG/SSA之結果圖。Fig. 1 is a graph showing the results of TG/SSA of the copper powders of the examples and the comparative examples.

第2圖呈示實施例及比較例之銅粉的TG/SSA之結果圖。Fig. 2 is a graph showing the results of TG/SSA of the copper powders of the examples and the comparative examples.

第3圖呈示實施例及比較例之銅粉以純銅粉當作基準之TG/SSA的結果圖。Fig. 3 is a graph showing the results of TG/SSA using pure copper powder as a reference for the copper powders of the examples and the comparative examples.

第4圖呈示實施例及比較例之銅粉以純銅粉當作基準之TG/SSA的結果圖。Fig. 4 is a graph showing the results of TG/SSA using pure copper powder as the reference for the copper powders of the examples and the comparative examples.

第5圖呈示實施例之銅粉的TG/SSA之結果圖。Fig. 5 is a graph showing the results of TG/SSA of the copper powder of the example.

第6圖呈示實施例之銅粉以純銅粉當作基準之TG/SSA的結果圖。Fig. 6 is a graph showing the results of TG/SSA using pure copper powder as a reference for the copper powder of the example.

Claims (5)

一種導電性糊膏用銅粉，其特徵為：粒子內部之矽(Si)含量為0.1atm%至10atm%，磷(P)含量為0.01atm%至0.3atm%，Si/P(atm比)為4至200。 A copper powder for conductive paste characterized in that the content of bismuth (Si) in the particles is from 0.1 atm% to 10 atm%, and the content of phosphorus (P) is from 0.01 atm% to 0.3 atm%, Si/P (atm ratio) It is 4 to 200. 如申請專利範圍第1項之導電性糊膏用銅粉，其中，粒子內部之銀(Ag)含量為0.1atm%至10atm%。 The copper powder for conductive paste according to claim 1, wherein the content of silver (Ag) in the particles is from 0.1 atm% to 10 atm%. 如申請專利範圍第1項之導電性糊膏用銅粉，其係藉由噴霧(Atomization)法而製造者。 The copper powder for conductive paste according to claim 1 of the patent application is produced by an atomization method. 如申請專利範圍第1項之導電性糊膏用銅粉，其中，在240℃及600℃之重量變化率(Tg(%))/比表面積(SSA)之差為1%/m2 /cm3 至30%/m2 /cm3 。The copper powder for conductive paste according to claim 1, wherein the difference in weight change rate (Tg (%)) / specific surface area (SSA) at 240 ° C and 600 ° C is 1% / m 2 /cm 3 to 30%/m 2 /cm 3 . 一種導電性糊膏，其特徵係含有如申請專利範圍第1至4項中任一項之導電性糊膏用銅粉。 A conductive paste containing the copper powder for conductive paste according to any one of claims 1 to 4.
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