JP2007067058A - Method of manufacturing electronic component aggregation and electronic component aggregation - Google Patents

Method of manufacturing electronic component aggregation and electronic component aggregation Download PDF

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JP2007067058A
JP2007067058A JP2005249268A JP2005249268A JP2007067058A JP 2007067058 A JP2007067058 A JP 2007067058A JP 2005249268 A JP2005249268 A JP 2005249268A JP 2005249268 A JP2005249268 A JP 2005249268A JP 2007067058 A JP2007067058 A JP 2007067058A
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metal
ultrafine
particles
copper
sintering
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Hideo Kikuchi
秀雄 菊地
Hirobumi Nakamura
博文 中村
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Kyocera Circuit Solutions Inc
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NEC Toppan Circuit Solutions Inc
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Abstract

<P>PROBLEM TO BE SOLVED: To enable to realize junction of metal terminals with large junction strength without requiring a long time. <P>SOLUTION: A metal terminal 2a of a first electronic component and a metal terminal 2b of a second electronic component are oppositely placed, metal ultra-fine particles 3 having the same quality as that of the metal terminals are arranged between the opposite metal terminals, and an oxide film is reduced and baked to obtain an electronic component aggregation having a junction portion for joining the metal terminals. In a preferred embodiment, metal terminals made of copper are joined with metal ultra-fine particles made of copper or copper alloy. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、有機樹脂基板あるいはセラミックス基板に配線パターンを形成した印刷配線板、半導体装置、その他のチップ部品等の電子部品の金属端子を他の電子部品の金属端子に接合する場合、あるいはその電子部品の内部の金属端子同士を接合する場合に、金属超微粒子を焼結させることで接合する方法、および、その方法で金属端子同士を接合された印刷配線板や半導体装置などの電子部品に関する。   The present invention relates to a case where a metal terminal of an electronic component such as a printed wiring board having a wiring pattern formed on an organic resin substrate or a ceramic substrate, a semiconductor device, or another chip component is joined to a metal terminal of another electronic component, or the electronic The present invention relates to a method of joining metal terminals by sintering metal ultrafine particles when joining the metal terminals inside the parts, and an electronic component such as a printed wiring board or a semiconductor device in which the metal terminals are joined together by the method.

従来、半導体装置や印刷配線板などの電子部品を製造する際には、階層的に順次金属端子同士を電気的に接合する処理を繰り返す必要があった。例えばシリコン基板同士を、両者の金属端子同士を電気的に接合することで一体化したシリコン基板複合体を製造する。次に、そのシリコン基板複合体の金属端子をセラミックス基板上の金属端子に電気的に接合して一体化した半導体装置を製造する。続いて、その半導体装置の金属端子を、有機樹脂基板の金属端子に電気的に接合して一体にしたマルチチップモジュールを製造する。更に、そのマルチチップモジュールの金属端子を有機樹脂基板から成る印刷配線板の金属端子に電気的に接合し一体にしたパッケージ基板を製造する。   Conventionally, when manufacturing electronic components such as semiconductor devices and printed wiring boards, it has been necessary to repeat the process of electrically joining metal terminals in a hierarchical manner. For example, a silicon substrate composite in which silicon substrates are integrated by electrically joining both metal terminals to each other is manufactured. Next, a semiconductor device in which the metal terminal of the silicon substrate composite is electrically joined to the metal terminal on the ceramic substrate and integrated is manufactured. Subsequently, the multi-chip module in which the metal terminal of the semiconductor device is electrically joined to the metal terminal of the organic resin substrate to be integrated is manufactured. Further, a package substrate is manufactured by electrically joining the metal terminals of the multichip module to the metal terminals of a printed wiring board made of an organic resin substrate.

従来は、これらの製造工程の初めに接合する金属端子同士は高温はんだ合金で接合し、最後の製造工程で接合する金属端子同士は低温はんだ合金で接合し、その中間の製造工程で接合する金属端子同士は、中間的な温度の融点を有するはんだ合金で接合する。このようにすることで後の金属端子同士のはんだ接合処理により先に接合した金属端子同士の接合部の接合信頼性を損なわないようにしていた。   Conventionally, metal terminals to be joined at the beginning of these manufacturing processes are joined with a high-temperature solder alloy, metal terminals to be joined at the last manufacturing process are joined with a low-temperature solder alloy, and metal is joined in an intermediate manufacturing process. The terminals are joined with a solder alloy having an intermediate temperature melting point. By doing in this way, it was made not to impair the joint reliability of the junction part of the metal terminals joined previously by the soldering process of subsequent metal terminals.

後の金属端子同士の接合の製造工程が先に接合した金属端子同士の接合を損なわないようにするための解決策は、焼結温度が低い金属超微粒子の焼結による金属接合で金属端子同士を接合することである。その焼結温度が低くても、焼結を終えた金属接合部分は、その金属の融点程度の高温までの耐熱性を有するようになるため、次の製造工程における金属端子同士の低い温度による接合処理で加熱する温度に十分耐えることができるようになるからである。このため、焼結温度が低い金属超微粒子の焼結による金属接合により、被接合物の金属端子同士を強固な金属接合で接合する技術が望まれていた。   The solution to prevent the manufacturing process of joining the metal terminals later from damaging the joining of the metal terminals joined first is metal joining by sintering metal ultrafine particles having a low sintering temperature. Is to join. Even if the sintering temperature is low, the sintered metal joint part has a heat resistance up to the high temperature of the melting point of the metal, so the metal terminals in the next manufacturing process are joined at a low temperature. This is because it can sufficiently withstand the heating temperature in the treatment. For this reason, the technique which joins the metal terminals of a to-be-joined object by firm metal joining by metal joining by sintering of metal ultrafine particles with a low sintering temperature was desired.

ところで、金属超微粒子を利用して金属接合を行う技術として、以下のような例が知られている。   By the way, the following examples are known as techniques for performing metal bonding using metal ultrafine particles.

第１の従来例として、特許文献１には、アルコールと混合したアルミニウムあるいは銅の超微粉を金属板上に塗布し、その上からもう一方の金属材を加熱・加圧し、超微粉を焼結することで２つの金属材を接合させる技術が開示されている。   As a first conventional example, Patent Document 1 discloses that an ultrafine powder of aluminum or copper mixed with alcohol is applied onto a metal plate, and the other metal material is heated and pressed from above to sinter the ultrafine powder. Thus, a technique for joining two metal materials is disclosed.

第２の従来例として、特許文献２には、超微粒子を２つの被接合材の間に設置し、不活性ガス雰囲気中あるいは真空中で、加熱・加圧し超微粒子を焼結させることで２つの被接合材を接合する技術が開示されている。   As a second conventional example, Patent Document 2 discloses that ultrafine particles are placed between two materials to be bonded, and heated and pressurized in an inert gas atmosphere or in vacuum to sinter the ultrafine particles. A technique for joining two workpieces is disclosed.

第３の従来例として、特許文献３には、第１の接続箇所と第２の接続箇所を接触させ、その接続箇所に金属超微粒子を吹き付け固着させることで第１の接続箇所と第２の接続箇所を電気的に接続させる技術が開示されている。   As a third conventional example, Patent Document 3 discloses that the first connection portion and the second connection portion are brought into contact with each other by spraying and fixing metal ultrafine particles to the connection portion. A technique for electrically connecting connection locations is disclosed.

第４の従来例として、特許文献４には、２つの金属の被接合面を、Ａｒ原子をスパッタリングし、それにより金属面を清浄化するとともに金属超微粒子を生成し堆積させ、その被接合面同士を加圧することで２つの金属を接合する技術が開示されている。   As a fourth conventional example, Patent Document 4 discloses that two metal surfaces to be bonded are sputtered with Ar atoms, thereby cleaning the metal surface and generating and depositing metal ultrafine particles. A technique for joining two metals by pressurizing each other is disclosed.

第５の従来例として、特許文献５には、被接合物の金属端子にＮｉ層を設け、この上に有機溶媒に分散させたＡｇ又はＡuの金属超微粒子を塗布し、大気中で３００℃以上に加熱し、有機物の炭素を酸化して除去し、加熱してＡｇ層を形成した他の被接合物の金属端子と重ねることで、被接合物同士を金属超微粒子を介して接合する技術が開示されている。   As a fifth conventional example, in Patent Document 5, a Ni layer is provided on a metal terminal of an object to be bonded, and Ag or Au metal ultrafine particles dispersed in an organic solvent are applied thereon, and 300 ° C. in the atmosphere. Technology to join the objects to be joined to each other via the metal ultrafine particles by heating and oxidizing and removing the organic carbon, and superimposing it on the metal terminals of other objects to be joined that have been heated to form the Ag layer. Is disclosed.

第６の従来例として、特許文献６には、有機物で被覆された金属超微粒子を第１の被接合物と第２の被接合物の間に挟んで第１の被接合物と第２の被接合物を加圧し、２００℃程度の温度で金属超微粒子を被覆している有機物を蒸発させるとともに金属超微粒子を焼結させ、第１と第２の被接合物を金属接合する技術が開示されている。   As a sixth conventional example, in Patent Document 6, the first and second objects to be bonded are sandwiched between the first and second objects to be bonded with the ultrafine metal particles coated with an organic substance. Disclosed is a technique for pressurizing an object to be bonded, evaporating an organic substance covering the metal ultrafine particles at a temperature of about 200 ° C., sintering the metal ultrafine particles, and metal-bonding the first and second objects to be bonded. Has been.

第７の従来例として、特許文献７には、銀の金属超微粒子を用いることが開示されている。銀は大気圧中で２５℃における酸化物の生成に要する酸化の標準自由エネルギー（エリンガム図で示される）が酸素分子１モルあたり−３０ｋジュール程度であり、酸化されにくいため、銀の金属超微粒子は焼結させ易い。特許文献７に開示された技術では、平均粒径５ｎｍの銀の金属超微粒子を印刷配線板の金属端子上に配置し３００℃で３分加熱して、印刷配線板の金属端子を半導体パッケージのバンプと接合するようにしている。   As a seventh conventional example, Patent Document 7 discloses the use of silver ultrafine metal particles. Silver has a standard free energy of oxidation (shown in the Ellingham diagram) required for the formation of an oxide at 25 ° C. in atmospheric pressure and is about −30 kjoule per mole of oxygen molecule, and is not easily oxidized. Is easy to sinter. In the technique disclosed in Patent Document 7, silver metal ultrafine particles having an average particle diameter of 5 nm are arranged on a metal terminal of a printed wiring board and heated at 300 ° C. for 3 minutes, and the metal terminal of the printed wiring board is attached to the semiconductor package. It is made to join with the bump.

また、第８の従来例として、特許文献８には、以下のような金属端子の接合方法が開示されている。第１の金属端子上に、平均粒径が１〜１０ｎｍの、金属塩を還元して形成したＡｇ，ＡｕまたはＰｂの金属超微粒子であって、周囲を有機性陰イオンの被覆層で被覆した複合金属超微粒子を金属粒子と混在させた金属ペーストを調整し、その金属ペーストにより高さ約２μｍの金属ペーストボールを形成する。続いて、その金属ペーストボール上に第２の金属端子を重ねて、２００〜２５０℃で３０分間の熱風炉により低温焼成を行うことで被覆層を離脱或いは分解して消滅させ、同時に金属超微粒子を溶融結合させることで、第１、第２の金属端子をその間の金属超微粒子により接合する。   Further, as an eighth conventional example, Patent Document 8 discloses the following method for joining metal terminals. Ag, Au, or Pb ultrafine metal particles formed by reducing a metal salt having an average particle diameter of 1 to 10 nm on the first metal terminal, and the periphery is covered with a coating layer of organic anions A metal paste in which composite metal ultrafine particles are mixed with metal particles is prepared, and a metal paste ball having a height of about 2 μm is formed from the metal paste. Subsequently, a second metal terminal is stacked on the metal paste ball, and the coating layer is removed or decomposed and disappeared by performing low-temperature firing in a hot air oven at 200 to 250 ° C. for 30 minutes. By melting and bonding, the first and second metal terminals are joined by ultrafine metal particles therebetween.

特開昭５５−１５２１０９号公報JP-A-55-152109 特開平４−１５８９９４号公報JP-A-4-158994 特開平４−２５１９４５号公報JP-A-4-251945 特開平６−９９３１７号公報JP-A-6-99317 特開平８−２６４７６５号公報JP-A-8-264765 特開２００１−２２５１８０号公報JP 2001-225180 A 特開２００４−１２８３５７号公報JP 2004-128357 A 特開２００１−１６８１４０号公報JP 2001-168140 A 「Sheldon K. Friedlander and Murray K. Wu, ” Linear rate law for the decay of the excess surface area of a coalescing solid particle,” Physical Review B49, pp. 3622-3624, 1994」"Sheldon K. Friedlander and Murray K. Wu," Linear rate law for the decay of the excess surface area of a coalescing solid particle, "Physical Review B49, pp. 3622-3624, 1994"

しかしながら、これら従来の技術には以下の欠点があった。   However, these conventional techniques have the following drawbacks.

第１の従来例は、金属超微粒子をアルコールと混合するが、この作業を大気中で行う場合は、銅の金属超微粒子でも、室温でも１時間ほど大気中に曝すと厚さが０．５ｎｍ以上の酸化皮膜が形成され、それが後の焼結を妨げるようになる。この従来例では、銅の金属超微粒子を焼結させるために、真空中で２００℃程度の加熱と加圧の保持時間を１０分以上必要としていた。これは、銅の金属超微粒子の表面に酸化皮膜が存在するため、その酸化皮膜の成分の酸素を銅材料中に拡散させることで消滅させる時間が必要となることから、この時間を要したと考えられる。   In the first conventional example, ultrafine metal particles are mixed with alcohol. However, when this operation is performed in the atmosphere, even if the ultrafine metal particles of copper are exposed to the atmosphere for about 1 hour at room temperature, the thickness is 0.5 nm. The above oxide film is formed, which hinders subsequent sintering. In this conventional example, in order to sinter the ultrafine metal particles of copper, a heating and pressurization holding time of about 200 ° C. in a vacuum is required for 10 minutes or more. This is because an oxide film exists on the surface of the copper ultrafine particles of copper, and it takes time to dissipate by diffusing oxygen as a component of the oxide film into the copper material. Conceivable.

第２の従来例では、銅の金属超微粒子を粉末のままで用い、加熱温度４００℃で加圧し３０分以上保持する必要があった。このように、銅の金属超微粒子ではその表面に酸化皮膜が形成され易いので、酸化皮膜が分解しその酸素が銅の母材に拡散する時間が銅の金属超微粒子の焼結に要する時間となることから、その時間だけ、銅の金属超微粒子を用いた金属同士の接合に時間を要するという問題があった。   In the second conventional example, it was necessary to use copper metal ultrafine particles as powders, pressurize them at a heating temperature of 400 ° C. and hold them for 30 minutes or more. As described above, since an oxide film is easily formed on the surface of copper ultrafine metal particles, the time required for the oxide metal film to decompose and the oxygen to diffuse into the copper base material is the time required for sintering the copper metal ultrafine particles. Therefore, there is a problem that it takes time to join the metals using the ultrafine metal particles of copper for that time.

第３の従来例は、金属超微粒子は、超微粒子生成室に配置された貯蔵部の金属を蒸発させることで酸化皮膜の無い金属超微粒子を形成する。そして、その金属超微粒子と搬送ガスとの混合気体を作り、その気体を搬送管で搬送し、その先端の直径約７０μｍの細いノズルから金属超微粒子と搬送ガスの混合気体を金属パッドとリード線の接合部に噴射させ金属超微粒子を堆積させることで金属超微粒子が焼結して成る金属塊を形成し、それにより金属パッドとリード線を接合していた。しかし、金属超微粒子の表面の活性が高いため、金属超微粒子がこれを噴出するノズルの開口部の内側に容易に付着し、付着した金属超微粒子に他の金属超微粒子が付着・焼結して堆積物を形成し、それがノズルの開口を塞ぎやすい。そのため、そのノズルを頻繁に交換しなければならないという欠点があった。   In the third conventional example, the ultrafine metal particles form ultrafine metal particles having no oxide film by evaporating the metal in the storage unit disposed in the ultrafine particle generation chamber. Then, a mixed gas of the metal ultrafine particles and the carrier gas is formed, the gas is conveyed by a carrier tube, and the gas mixture of the metal ultrafine particles and the carrier gas is transferred from a thin nozzle having a diameter of about 70 μm to the metal pad and the lead wire. The metal ultrafine particles were deposited by spraying onto the joints to form a metal lump formed by sintering the ultrafine metal particles, thereby joining the metal pad and the lead wire. However, since the surface activity of the metal ultrafine particles is high, the metal ultrafine particles easily adhere to the inside of the nozzle opening from which the other metal ultrafine particles adhere and sinter. A deposit is formed, which tends to block the nozzle opening. For this reason, the nozzle has to be frequently replaced.

第４の従来例は、金属の被接合面を、Ａｒ原子をスパッタリングし、それにより金属面を清浄化するとともに金属超微粒子を生成し堆積させるが、その金属面に堆積する金属超微粒子の粒径を適切な径にコントロールすることが難しいという問題があった。すなわち、金属の被接合面に堆積された金属超微粒子は、その粒径が小さいと速やかに焼結し平坦な金属面に変化してしまい、平坦な金属面になると焼結の活性を失ってしまう問題があった。他方、粒径の大きい金属超微粒子が存在すると、その金属超微粒子は、その焼結に多くの時間を要し、その金属超微粒子の焼結時間に律速されることにより金属の被接合面同士を接合する時間に長時間を要するという問題があった。   In the fourth conventional example, Ar atoms are sputtered on the surface to be joined of metal, thereby cleaning the metal surface and generating and depositing ultrafine metal particles. The ultrafine metal particles deposited on the metal surface are deposited. There was a problem that it was difficult to control the diameter to an appropriate diameter. In other words, the ultrafine metal particles deposited on the surface to be joined of the metal quickly sinter and change to a flat metal surface when the particle size is small, and lose the sintering activity when the metal surface becomes flat. There was a problem. On the other hand, if there are metal ultrafine particles having a large particle size, the metal ultrafine particles take a long time to sinter, and are controlled by the sintering time of the metal ultrafine particles. There is a problem that it takes a long time to bond the two.

第５の従来例および第７の従来例では、Ａｇを用いるため、銀はマイグレーションを生じ、銀を用いた接合部分とその近くの配線パターンとの間の絶縁性を悪くするという問題があった。   In the fifth conventional example and the seventh conventional example, since Ag is used, migration of silver occurs, and there is a problem that the insulation between the joint portion using silver and the wiring pattern in the vicinity thereof deteriorates. .

第６の従来例では、銅の金属超微粒子を脂肪酸錯体などの有機物で被覆した状態で第１の被接合物と第２の被接合物の間に挟んで、２００℃程度の温度に加熱することで金属超微粒子が焼結する際に、金属超微粒子の表面の一部に残留した脂肪酸錯体を、金属超微粒子の焼結構造内に閉じ込める。金属超微粒子の焼結構造内に閉じ込められた脂肪酸錯体は、焼結の進行に伴い炭化し、その炭素が金属超微粒子の焼結構造内に残留しそれ以上の焼結を妨げるため焼結構造の機械的強度を弱めるという問題があった。   In the sixth conventional example, copper ultrafine particles of copper are covered with an organic substance such as a fatty acid complex, and are sandwiched between a first object to be bonded and a second object to be bonded, and heated to a temperature of about 200 ° C. Thus, when the ultrafine metal particles are sintered, the fatty acid complex remaining on a part of the surface of the ultrafine metal particles is confined in the sintered structure of the ultrafine metal particles. The fatty acid complex trapped in the sintered structure of ultrafine metal particles is carbonized as the sintering proceeds, and the carbon remains in the sintered structure of ultrafine metal particles, preventing further sintering. There was a problem of weakening the mechanical strength.

第８の従来例は、被覆層を離脱或いは分解して消滅させる必要があるため、第１、第２の金属端子間に金属ペーストボールの表面を露出させ、そこに露出した金属ペーストボールの表面の露出した金属超微粒子の被覆層を離脱或いは分解して消滅させてその表面の金属超微粒子を焼結させることで２つの金属端子を接合していた。   In the eighth conventional example, it is necessary to remove or disassemble the coating layer so that the surface of the metal paste ball is exposed between the first and second metal terminals, and the surface of the metal paste ball exposed there The exposed metal ultrafine particle coating layer was removed or decomposed to disappear, and the metal ultrafine particles on the surface were sintered to join the two metal terminals.

しかし、第８の従来例では、金属超微粒子集合の閉じた空間内に金属超微粒子の被覆層が閉じ込められると、その被覆層の有機物の分解生成物の炭素の逃げ場が無く金属接合部に残留してしまうため、その炭素が金属超微粒子の集合の金属接合を弱くしてしまい金属超微粒子の集合の内部の金属接合が弱いという欠点があった。そのため、金属超微粒子の集合の体積に対する露出表面の面積を大きくする必要から、２つの金属端子間に金属ペーストボールを設置することで、その直径と高さをほぼ同じ大きさの形状にしていた。すなわち、その直径の高さに対する比が１０倍程度に大きい層状の金属超微粒子層を焼結させることによる緻密な金属層による金属端子同士の強固な金属接合が行えない欠点があった。   However, in the eighth conventional example, when the coating layer of the ultrafine metal particles is confined in the closed space of the aggregate of ultrafine metal particles, there is no escape space for the carbon of the decomposition product of the organic matter of the coating layer and remains in the metal joint. As a result, the carbon weakens the metal bonding of the set of ultrafine metal particles, and the metal bond inside the set of ultrafine metal particles is weak. For this reason, since it is necessary to increase the area of the exposed surface with respect to the volume of the aggregate of ultrafine metal particles, a metal paste ball is installed between the two metal terminals, so that the diameter and height thereof are approximately the same size. . That is, there is a defect that the metal terminals cannot be firmly bonded to each other by the dense metal layer by sintering the layered ultrafine metal particle layer whose ratio of the diameter to the height is about 10 times larger.

更に、第８の従来例では、２００〜２５０℃の温度で３０分間の熱風炉により焼成する必要があり、処理温度も高く、処理時間も長時間を要するという欠点があった。また、第８の従来例で用いられている鉛については、鉛の融点が３２７℃と低く、また、その平均粒径が１〜１０ｎｍと小さいために鉛の超微粒子の融点が２００℃以下になり、２００℃以上では溶融した鉛超微粒子の表面の酸化皮膜が裂け内部の鉛が露出して接合することで鉛超微粒子同士が金属接合すると考えられる。そのため、第８の従来例では、鉛以外の、融点が４００℃以上の金属で、酸化皮膜が形成され易い、酸化の標準自由エネルギーが酸素分子１モルあたり−１００ｋジュール以下の金属による超微粒子の場合は、その金属に形成される酸化皮膜が焼結を妨害するため、その金属超微粒子の焼結には、より高い温度とより長い時間を要する問題があった。   Further, in the eighth conventional example, it is necessary to perform firing in a hot air oven at a temperature of 200 to 250 ° C. for 30 minutes, the processing temperature is high, and the processing time is long. The lead used in the eighth conventional example has a lead melting point as low as 327 ° C., and the average particle size is as small as 1 to 10 nm. Thus, at 200 ° C. or higher, the oxide film on the surface of the melted lead ultrafine particles is split, and the lead inside is exposed and joined, so that it is considered that the lead ultrafine particles are metal-bonded. Therefore, in the eighth conventional example, ultrafine particles of metals other than lead, which have a melting point of 400 ° C. or more, are easy to form an oxide film, and have a standard free energy of oxidation of −100 kJ or less per mole of oxygen molecule. In this case, since the oxide film formed on the metal hinders the sintering, there is a problem that the sintering of the ultrafine metal particles requires a higher temperature and a longer time.

本発明の課題は、かかる従来の問題を解決することにあり、金属端子の接合を、長時間を要することなく大きな接合強度で実現できるようにすることにある。   An object of the present invention is to solve such a conventional problem, and to enable metal terminal bonding to be realized with high bonding strength without requiring a long time.

本発明は、金属端子同士を、特に、酸化皮膜が形成され易い、酸化の標準自由エネルギーが酸素分子１モルあたり−１００ｋジュール以下で、融点が４００℃以上の金属からなる金属超微粒子を焼結させて金属結合する技術である。   The present invention sinters metal terminals, particularly metal ultrafine particles made of a metal having a standard free energy of oxidation of -100 kJ or less per mol of oxygen molecule and a melting point of 400 ° C. or more, in which an oxide film is easily formed. This is a technology for metal bonding.

すなわち、酸化皮膜が形成されている金属超微粒子を第１の金属端子上に配置し、次に、その酸化皮膜を還元して除去し純粋な金属超微粒子に関して理論的に予想されるまでの活性度で、金属超微粒子の焼結機能を発現させ、次に、第２の金属端子を、その金属超微粒子を間に挟んで第１の金属端子に重ね合わせ、金属超微粒子を焼結させることで第１の金属端子に第２の金属端子を金属接合させる技術である。   That is, the metal ultrafine particles on which the oxide film is formed are arranged on the first metal terminal, and then the oxide film is reduced and removed, and the activity up to the theoretical expectation for pure metal ultrafine particles is achieved. The second metal terminal is superimposed on the first metal terminal with the metal ultrafine particle in between, and the metal ultrafine particle is sintered. In this technique, the second metal terminal is bonded to the first metal terminal.

そのため、本発明では、第１の金属端子と第２の金属端子の間に、銅、鉄、ニッケル、コバルト、チタンなどの、融点が４００℃以上あり、特に、大気圧中で２５℃における酸化物の生成に要する酸化の標準自由エネルギー（エリンガム図で示される）が酸素分子１モルあたり−１００ｋジュール以下であって酸化皮膜が形成され易い金属からなる金属超微粒子を挟んで、第１の金属端子と第２の金属端子を、金属超微粒子を介して金属接合する。その金属超微粒子には、印刷配線板あるいは半導体装置のような電子部品の加工条件に合わせた適切な粒径のものを用いる。そして、先ず、その金属超微粒子を第１の金属端子に配置した後、金属超微粒子の酸化皮膜を、適切な温度と時間以内で還元させることで、第１の金属端子の表面に、その後に焼結する活性を残した金属超微粒子の層を形成する。次に、その金属超微粒子の層の表面に第２の金属端子を重ね合わせ、焼結を生じる適切な温度で金属超微粒子を焼結させることで、第１、第２の金属端子を金属超微粒子によって金属接合させるようにしている。   Therefore, in the present invention, the melting point of copper, iron, nickel, cobalt, titanium, or the like between the first metal terminal and the second metal terminal is 400 ° C. or higher, and in particular, oxidation at 25 ° C. under atmospheric pressure. The first metal is sandwiched between metal ultrafine particles made of a metal that has a standard free energy of oxidation (shown in the Ellingham diagram) required for the production of the product and is less than −100 kJoules per mole of oxygen molecules and an oxide film is easily formed. The terminal and the second metal terminal are metal-bonded via ultrafine metal particles. As the metal ultrafine particles, those having an appropriate particle size in accordance with the processing conditions of an electronic component such as a printed wiring board or a semiconductor device are used. First, after the ultrafine metal particles are disposed on the first metal terminal, the oxide film of the ultrafine metal particles is reduced within an appropriate temperature and time, so that the surface of the first metal terminal is thereafter A layer of ultrafine metal particles that retains the activity of sintering is formed. Next, the second metal terminal is superposed on the surface of the layer of the metal ultrafine particles, and the metal ultrafine particles are sintered at an appropriate temperature at which sintering occurs, whereby the first and second metal terminals are made to be metal ultrafine. Metal particles are joined by fine particles.

本発明によれば、第１の電子部品の第１の金属端子の表面に、粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を分散した液体を吐出し、前記液体の媒体を蒸発させることで厚さ方向に直角な方向の直径が厚さの１０倍以上の金属超微粒子層を形成するとともに、前記金属超微粒子層における前記金属超微粒子の表面の酸化皮膜を、還元性ガスにより、前記金属超微粒子の粒径により定まる焼結時間よりも短い時間で還元する第１の工程と、次に、前記金属超微粒子層を形成した前記第１の金属端子に対向させて第２の電子部品の第２の金属端子を接触させ加熱し加圧することで、前記第１の金属端子及び第２の金属端子同士を、その間の前記金属超微粒子を焼結させることで金属接合させる第２の工程とを有することを特徴とする電子部品の集合体の製造方法が提供される。   According to the present invention, a liquid in which ultrafine metal particles having a particle diameter of 0.5 nm to 70 nm are dispersed is discharged onto the surface of the first metal terminal of the first electronic component, and the liquid medium is evaporated. And forming a metal ultrafine particle layer whose diameter in a direction perpendicular to the thickness direction is 10 times or more of the thickness, and forming an oxide film on the surface of the metal ultrafine particle in the metal ultrafine particle layer with a reducing gas, A first step of reducing in a time shorter than a sintering time determined by the particle size of the ultrafine metal particles, and then a second electronic component facing the first metal terminal on which the ultrafine metal particle layer is formed A second step of bringing the first metal terminal and the second metal terminal into contact with each other by sintering the metal ultrafine particles therebetween by bringing the second metal terminal into contact and heating and pressurizing. An electron characterized by having Method for producing a collection of goods are provided.

本発明によればまた、第１の電子部品の第１の金属端子と第２の電子部品の第２の金属端子を接合させた接合部分を有する電子部品の集合体であって、該接合部分が、対向する前記第１、第２の金属端子の間に粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を焼結させて成る、厚さ方向に直角な方向の直径が厚さの１０倍以上の金属層を有することを特徴とする電子部品の集合体が提供される。   According to the present invention, there is also provided an electronic component assembly having a joint portion obtained by joining the first metal terminal of the first electronic component and the second metal terminal of the second electronic component, the joint portion. However, between the first and second metal terminals facing each other, a metal ultrafine particle having a particle diameter of 0.5 nm to 70 nm is sintered, and the diameter perpendicular to the thickness direction is 10 mm. There is provided an assembly of electronic components characterized in that it has double or more metal layers.

本発明によれば更に、第１の電子部品の第１の金属端子と第２の電子部品の第２の金属端子を接合させた接合部分を有する電子部品の集合体であって、該接合部分が、対向する前記第１、第２の金属端子の間に、銅あるいは銅成分が５０原子％以上の銅合金からなる、粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を焼結させて成る、厚さ方向に直角な方向の直径が厚さの１０倍以上の金属層を有することを特徴とする電子部品の集合体が提供される。   According to the present invention, there is further provided an assembly of electronic components having a joint portion obtained by joining the first metal terminal of the first electronic component and the second metal terminal of the second electronic component, the joint portion. However, between the first and second metal terminals facing each other, ultrafine metal particles having a particle diameter of 0.5 nm to 70 nm made of copper or a copper alloy having a copper component of 50 atomic% or more are sintered. There is provided an assembly of electronic components characterized by having a metal layer having a diameter in a direction perpendicular to the thickness direction of 10 times or more of the thickness.

本発明によれば、例えば銅について言えば、その金属超微粒子を分散液に分散させた状態で、第１の電子部品の第１の金属端子の表面に配置し、分散液を蒸発させることで銅の金属超微粒子層を形成し、その銅の金属超微粒子層の上に第２の電子部品の第２の金属端子を重ね、金属超微粒子を、銅の融点より低い温度で焼結することで、第１、第２の金属端子を銅の金属超微粒子に金属接合させるようにしたことにより、第１の金属端子と第２の金属端子を金属超微粒子に、短時間かつ低温度でしかも大きな接合強度で金属結合させることができる。   According to the present invention, for example, for copper, the metal ultrafine particles are disposed on the surface of the first metal terminal of the first electronic component while being dispersed in the dispersion, and the dispersion is evaporated. Forming a copper ultrafine particle layer of copper, superimposing the second metal terminal of the second electronic component on the copper ultrafine particle layer, and sintering the ultrafine metal particles at a temperature lower than the melting point of copper. The first and second metal terminals are bonded to the ultrafine metal particles of copper so that the first metal terminals and the second metal terminals are made into ultrafine metal particles in a short time and at a low temperature. Metal bonding can be performed with high bonding strength.

本発明によればまた、還元性ガス、例えば水素の大気圧水素プラズマあるいは水素原子を多量に含む還元性ガスにより金属超微粒子の表面の酸化皮膜をその焼結速度よりも速く還元させて除去し、次に、焼結の活性がある状態の金属超微粒子を焼結させるようにしたことにより、第１、第２の金属端子同士を強固に金属接合させることができる。   According to the present invention, the oxide film on the surface of the metal ultrafine particles can be reduced and removed faster than the sintering rate by a reducing gas such as atmospheric hydrogen plasma of hydrogen or a reducing gas containing a large amount of hydrogen atoms. Next, the first and second metal terminals can be strongly bonded to each other by sintering the ultrafine metal particles having a sintering activity.

［本発明の原理］
本発明は、第１の金属端子上に金属、例えば銅の金属超微粒子（いわゆるナノ粒子）による、厚さ方向に直角な方向の直径がその厚さの１０倍以上ある金属超微粒子層を配置し、その金属超微粒子の表面の酸化皮膜を還元性気体の存在下で生起されたプラズマあるいは原子状水素の雰囲気により還元し酸化皮膜が除去された生の金属表面を露出させ、第１の金属端子上の金属超微粒子層に第２の金属端子を重ねて、第１、第２の金属端子をその金属超微粒子を焼結させることで直径が厚さの１０倍以上ある扁平な構造で緻密な金属層を形成することにより接合するという着想に基づいている。しかし、この場合、第１の金属端子上の金属超微粒子の粒径が小さいと、それは還元後に速やかに焼結し平坦な金属面に変化してしまい、平坦な金属面になると焼結の活性を失ってしまう。他方、粒径の大きい金属超微粒子が存在すると、その金属超微粒子は、その焼結に多くの時間を要し、その金属超微粒子の焼結時間に律速されることにより金属の被接合面同士を接合する時間に長時間を要する。このように、金属端子間に金属超微粒子を介在させることで金属接合させることは容易ではない。 [Principle of the present invention]
In the present invention, a metal ultrafine particle layer having a diameter in the direction perpendicular to the thickness direction of 10 times or more of a metal, such as copper metal ultrafine particles (so-called nanoparticles), is disposed on the first metal terminal. Then, the oxide film on the surface of the metal ultrafine particles is reduced by plasma or atomic hydrogen atmosphere generated in the presence of a reducing gas to expose the raw metal surface from which the oxide film has been removed, and the first metal is exposed. The second metal terminal is overlapped on the metal ultrafine particle layer on the terminal, and the first and second metal terminals are sintered with the metal ultrafine particles, so that the diameter is more than 10 times as thick as the flat structure. This is based on the idea of joining by forming a simple metal layer. However, in this case, if the particle size of the metal ultrafine particles on the first metal terminal is small, it will sinter quickly after reduction and change to a flat metal surface. Will be lost. On the other hand, if there are metal ultrafine particles having a large particle size, the metal ultrafine particles take a long time to sinter, and are controlled by the sintering time of the metal ultrafine particles. It takes a long time to join. Thus, it is not easy to perform metal bonding by interposing metal ultrafine particles between metal terminals.

上記の問題点に対し、本発明は、金属、例えば銅の金属超微粒子の焼結温度は、その金属超微粒子の粒径が小さくなるとともに低下し、また、その焼結温度は金属超微粒子の粒径が小さくなることにより低下する融点により十分低い温度になることを利用している。   In contrast to the above problems, the present invention is such that the sintering temperature of ultrafine metal particles of metal, such as copper, decreases as the particle size of the ultrafine metal particles decreases, and the sintering temperature of the ultrafine metal particles is low. The fact that the temperature becomes sufficiently low due to the melting point that decreases as the particle size decreases is utilized.

本発明は、図１に示すように、特に、融点が４００℃で、大気圧中で２５℃における酸化物の生成に要する酸化の標準自由エネルギー（エリンガム図で示される）が酸素分子１モルあたり−１００ｋジュール以下であって酸化皮膜が形成され易い金属の金属超微粒子３による、厚さ方向に直角な方向の直径がその厚さの１０倍以上ある金属超微粒子層３ｂを、印刷配線板あるいは半導体装置などの電子部品の金属端子２ａと別の電子部品の金属端子（図示せず）との間に設置し、両者を接合する。この種の金属は、銅、鉄、ニッケル、コバルト、チタンなどが考えられる。また、標準自由エネルギーが−１００ｋジュールを越える銀や金の金属超微粒子３についても、薄い酸化皮膜の存在により生の金属に比べて焼結速度が低下しているが、その酸化皮膜を還元除去することで焼結の速度を速め、それらの金属超微粒子を電子部品の金属端子間に介在させた速やかな焼結によりその金属端子同士を接合することができる。これらの金属超微粒子３は、製造する電子部品の加工条件に合わせた焼結機能を有する適切な粒径のものを用いる。そして、先ず、その金属超微粒子３を、電子部品の金属端子（第１の金属端子）２ａに配置した後に、その酸化皮膜を焼結が進行しない適切な温度と時間以内で還元させることで、金属端子２ａの表面に焼結の活性を有する金属超微粒子３の層３ｂを形成する。ここで、金属超微粒子層３ｂのサイズを厚さ及び直径で表しているが、これは金属超微粒子層３ｂが扁平な円形に近い形状になり易いからである。そこで、仮に金属超微粒子層３ｂが矩形状になるような場合にはその幅のサイズが直径として表される。   In the present invention, as shown in FIG. 1, in particular, the standard free energy of oxidation (shown in the Ellingham diagram) required for the formation of an oxide at a melting point of 400 ° C. and atmospheric pressure at 25 ° C. A metal ultrafine particle layer 3b having a diameter in a direction perpendicular to the thickness direction of 10 to 10 times or more of a metal ultrafine particle 3 that is less than -100 kjoule and easily forms an oxide film is formed on a printed wiring board or It installs between the metal terminal 2a of electronic components, such as a semiconductor device, and the metal terminal (not shown) of another electronic component, and joins both. Examples of this type of metal include copper, iron, nickel, cobalt, and titanium. The silver and gold metal ultrafine particles 3 whose standard free energy exceeds -100 kjoules also has a lower sintering speed than the raw metal due to the presence of a thin oxide film, but the oxide film is reduced and removed. By doing so, the speed of sintering can be increased, and the metal terminals can be joined to each other by rapid sintering in which the ultrafine metal particles are interposed between the metal terminals of the electronic component. As these ultrafine metal particles 3, those having an appropriate particle size having a sintering function in accordance with the processing conditions of the electronic component to be manufactured are used. And, first, after placing the metal ultrafine particles 3 on the metal terminal (first metal terminal) 2a of the electronic component, the oxide film is reduced within an appropriate temperature and time at which sintering does not proceed, A layer 3b of ultrafine metal particles 3 having sintering activity is formed on the surface of the metal terminal 2a. Here, the size of the metal ultrafine particle layer 3b is represented by the thickness and the diameter. This is because the metal ultrafine particle layer 3b tends to have a shape close to a flat circle. Therefore, if the ultrafine metal particle layer 3b has a rectangular shape, the size of the width is expressed as the diameter.

次に、図２に示すように、金属超微粒子層３ｂを別の電子部品の金属端子（第２の金属端子）２ｂと重ね合わせて加圧し、焼結を生じる適切な温度と時間をかけて、２つの金属端子２ａ，２ｂ間の金属超微粒子３を焼結させることで２つの金属端子２ａ，２ｂを金属接合させる。   Next, as shown in FIG. 2, the metal ultrafine particle layer 3b is superposed on the metal terminal (second metal terminal) 2b of another electronic component and pressed, and an appropriate temperature and time for causing sintering are taken. The metal ultrafine particles 3 between the two metal terminals 2a and 2b are sintered to join the two metal terminals 2a and 2b to each other.

例えば、１気圧２５℃での酸化の標準自由エネルギーが酸素分子１モルあたり約−３００ｋジュールである銅の金属超微粒子３を用いる場合は、その金属超微粒子３の直径が２ｎｍから７０ｎｍのものを分散液３ａに分散させる。この分散液３ａ中の銅の金属超微粒子３には、その表面に厚さが１ｎｍ程度の酸化皮膜が形成される。その酸化皮膜が銅の金属超微粒子３同士の結合を妨げるので、個々の銅の金属超微粒子３が分散液３ａ中で焼結せず、独立して存在するよう良く分散される。   For example, when using copper ultrafine metal particles 3 having a standard free energy of oxidation of about -300 kjoule per mole of oxygen molecule at 1 atm and 25 ° C, the diameter of the ultrafine metal particles 3 is 2 nm to 70 nm. Disperse in dispersion 3a. An oxide film having a thickness of about 1 nm is formed on the surface of the copper ultrafine metal particles 3 in the dispersion 3a. Since the oxide film prevents the bonding between the copper metal ultrafine particles 3, the individual copper metal ultrafine particles 3 are not sintered in the dispersion 3 a and are well dispersed so that they exist independently.

次に、その分散液３ａを、図１に参照番号８で示すディスペンサーやインクジェットプリンタ等により、第１の絶縁基板（樹脂シート）５−１上の銅の第１の金属端子２ａに吐出し、その分散液３ａを乾燥させ、厚さ方向に直角な方向の直径が１０μｍから１００μｍ程度で厚さが０．１μｍから１μｍ程度、すなわち直径が厚さの１０倍以上の銅の金属超微粒子層３ｂを形成する。   Next, the dispersion liquid 3a is discharged to the first metal terminal 2a of copper on the first insulating substrate (resin sheet) 5-1 by a dispenser or an ink jet printer indicated by reference numeral 8 in FIG. The dispersion liquid 3a is dried, and a copper ultrafine metal particle layer 3b having a diameter in a direction perpendicular to the thickness direction of about 10 μm to 100 μm and a thickness of about 0.1 μm to 1 μm, that is, a diameter of 10 times or more the thickness. Form.

次に、銅の金属超微粒子３の表面を、水素、アンモニア、一酸化炭素等の還元性原料ガスを用いた大気圧プラズマの還元性ガス４に接触させる。還元性ガス４としては、この他に、還元性原料ガスを加熱した触媒体に接触させて、その表面での接触分解反応を利用して分解することで原子状水素を多量に生成し、その原子状水素を大気圧のアルゴンガスや窒素ガスに混入させて形成した還元性ガスを用いても良い。このように原子状水素を混入させた還元性ガスも、還元性の大気圧プラズマによる還元性ガス４と同じく還元力が強いので、以下の処理で用いることができる。これらの還元性ガス４により、金属超微粒子３の表面に付着した炭素成分を、メタンガスなどのガスに変えることで除去する。また、この還元性ガス４は、これと同時に、銅の金属超微粒子３の酸化皮膜を、酸化皮膜が除去された後の銅の金属超微粒子３の焼結速度よりも速い速度で還元することができる。また、この工程では、減圧環境においてアルゴンガスのスパッタ処理を行うことによっても、銅の金属超微粒子３の表面の炭素成分と酸化皮膜を同時に除去することができる。   Next, the surface of the copper ultrafine metal particles 3 is brought into contact with a reducing gas 4 of atmospheric pressure plasma using a reducing source gas such as hydrogen, ammonia, carbon monoxide or the like. In addition to this, as the reducing gas 4, a reducing source gas is brought into contact with a heated catalyst body and decomposed using a catalytic cracking reaction on the surface thereof to generate a large amount of atomic hydrogen. A reducing gas formed by mixing atomic hydrogen with atmospheric argon gas or nitrogen gas may be used. Since the reducing gas mixed with atomic hydrogen in this way has a strong reducing power like the reducing gas 4 by reducing atmospheric pressure plasma, it can be used in the following processing. With these reducing gases 4, the carbon component adhering to the surface of the metal ultrafine particles 3 is removed by changing it to a gas such as methane gas. At the same time, the reducing gas 4 reduces the oxide film of the copper metal ultrafine particles 3 at a speed higher than the sintering speed of the copper metal ultrafine particles 3 after the oxide film is removed. Can do. In this step, the carbon component and the oxide film on the surface of the copper ultrafine metal particles 3 can also be removed simultaneously by performing an argon gas sputtering process in a reduced pressure environment.

最後に、図２に示すように、そのようにして焼結の活性を有する銅の金属超微粒子層３ｂ上に、第２の絶縁基板５−２上の１００℃から３００℃に加熱した第２の金属端子２ｂを重ねて加圧することで、第１の金属端子２ａと第２の金属端子２ｂの間の銅の金属超微粒子３を焼結させ、それにより第１の金属端子２ａと第２の金属端子２ｂを強固に金属接合させる。   Finally, as shown in FIG. 2, the second ultra-fine copper particle layer 3b having the sintering activity is heated from 100 ° C. to 300 ° C. on the second insulating substrate 5-2. By superposing and pressing the metal terminal 2b, the copper metal ultrafine particles 3 between the first metal terminal 2a and the second metal terminal 2b are sintered, whereby the first metal terminal 2a and the second metal terminal 2b are sintered. The metal terminal 2b is firmly metal-bonded.

ここで、金属超微粒子３の焼結速度は、金属超微粒子３の粒径と温度により定まり、その温度は、金属超微粒子３の融点よりも低い温度で焼結する。金属超微粒子３の焼結時間ｔは、非特許文献１に開示されている実験結果に良く合う以下の式（１）により計算できる。   Here, the sintering speed of the metal ultrafine particles 3 is determined by the particle size and temperature of the metal ultrafine particles 3, and the temperature is sintered at a temperature lower than the melting point of the metal ultrafine particles 3. The sintering time t of the ultrafine metal particles 3 can be calculated by the following equation (1) that is well suited to the experimental results disclosed in Non-Patent Document 1.

ｔ＝(３kＢＴ＊Ｎ)／(６４πＥ＊Ｄ) （１） t = (3k B T * N ) / (64πE * D) (1)

式（１）において、Ｔは温度である。また、Ｎは焼結後の体積の金属超微粒子３の原子数で、銅の金属超微粒子３の場合は、Ｎ=(４π／３)Ｒ３／(０．０１１８ｎｍ３)（Ｒは焼結後の銅の金属超微粒子３の半径）である。ｔは経過時間である。Ｅは気体と接する表面自由エネルギーであり、銅の金属超微粒子３の場合は、１６７０erg/cm2である。ｋＢはボルツマン定数１．３８＊１０−２３ (J／deg)である。また、Ｄは拡散係数であり、以下の式（２）であらわされる。 In Formula (1), T is temperature. N is the number of atoms of the ultrafine metal particles 3 in the volume after sintering. In the case of ultrafine metal particles 3 of copper, N = (4π / 3) R 3 /(0.0118 nm 3 ) (R is sintered) This is the radius of the copper ultrafine metal particles 3 later. t is the elapsed time. E is the surface free energy in contact with the gas, and is 1670 erg / cm 2 in the case of the ultrafine metal particles 3 of copper. k B is the Boltzmann constant 1.38 * 10 −23 (J / deg). D is a diffusion coefficient, and is expressed by the following equation (2).

Ｄ＝Ｄｏｅｘｐ(−Ｑ／(ｋＢ＊ＮＡ＊Ｔ)) （２）
但し、ＮＡはアボガドロ数６．０２＊１０２３ (／mol)である。 D = Doexp (-Q / (k B * N A * T)) (2)
However, N A is Avogadro's number 6.02 * 10 23 (/ mol) .

式（２）の拡散係数は、表面拡散係数あるいは粒界拡散係数が用いられる。銅の金属超微粒子３では、粒界拡散係数を用いるのが妥当と考えられ、その拡散係数は、振動数因子Ｄｏ＝０．１cm２／sec、粒界拡散の活性化エネルギーＱは１０５kJ／molである。 As the diffusion coefficient of equation (2), a surface diffusion coefficient or a grain boundary diffusion coefficient is used. It is considered appropriate to use the grain boundary diffusion coefficient for the copper ultrafine metal particles 3. The diffusion coefficient is a frequency factor Do = 0.1 cm 2 / sec, and the activation energy Q of the grain boundary diffusion is 105 kJ / mol. It is.

図３に、本発明者により式（１）を銅の金属超微粒子３に適用して計算した焼結時間ｔを、銅の金属超微粒子３の半径Ｒ毎に示す。但し、このＲは、焼結以前の複数の銅の金属超微粒子３が結合した結果の体積の半径と解し、焼結時間は、その体積の銅の金属超微粒子３の形成に要する時間と解することができる。そのため、この焼結を開始する元の銅の金属超微粒子３の半径はおおむねその半分程度と考え、図３に示すＲは、焼結する以前の銅の金属超微粒子３の直径にあたると考える。すなわち、直径ｄの金属超微粒子８つが焼結し直径２ｄの金属超微粒子が形成される時間が式（１）で計算される焼結時間ｔと考える。そこで、以下ではこのＲを金属超微粒子の直径d（焼結する以前の金属超微粒子の直径）と呼んで説明を行う。   FIG. 3 shows the sintering time t calculated by applying the formula (1) to the copper metal ultrafine particles 3 by the inventor for each radius R of the copper metal ultrafine particles 3. However, this R is understood to be the radius of the volume resulting from the combination of a plurality of copper metal ultrafine particles 3 before sintering, and the sintering time is the time required to form copper metal ultrafine particles 3 of that volume. Can be solved. Therefore, the radius of the original copper metal ultrafine particles 3 for starting the sintering is considered to be about half of that, and R shown in FIG. 3 is considered to correspond to the diameter of the copper ultrafine metal particles 3 before sintering. That is, the time for which the 8 ultrafine metal particles having the diameter d are sintered and the ultrafine metal particles having the 2d diameter are formed is considered as the sintering time t calculated by the equation (1). Therefore, in the following description, this R will be referred to as the diameter d of the ultrafine metal particles (the diameter of the ultrafine metal particles before sintering).

図３から、温度Ｔが１００℃から３００℃の範囲では、元の銅の金属超微粒子３の直径dが１０ｎｍ程度の場合、２００℃では１秒程度で焼結するが１００℃では１０００倍の１０００秒かかり、温度により焼結時間に大きな開きがあることがわかる。また、同じ２００℃の温度でも、金属超微粒子３の直径が大きくなると、直径dが２０ｎｍでは７秒、d＝４０ｎｍでは５０秒、d＝７０ｎｍでは２８０秒かかるというように、直径ｄにより焼結時間に大きな開きがある。   From FIG. 3, when the temperature T is in the range of 100 ° C. to 300 ° C., when the diameter d of the original ultrafine metal particles 3 of copper is about 10 nm, sintering is performed in about 1 second at 200 ° C., but 1000 times at 100 ° C. It takes 1000 seconds, and it can be seen that there is a large difference in the sintering time depending on the temperature. Further, even at the same temperature of 200 ° C., when the diameter of the metal ultrafine particles 3 is increased, the diameter d is 7 seconds when the diameter is 20 nm, 50 seconds when the d = 40 nm, and 280 seconds when the d = 70 nm. There is a big gap in time.

このグラフから、銅の金属超微粒子３の焼結速度は、温度が２００℃と３００℃では１００倍の速度差があり、温度が１００℃と３００℃では１０万倍の速度差があることがわかる。このような温度による焼結の速度差を利用することで、比較的低温で、銅の金属超微粒子３の粒径とその温度により定まる焼結時間以内の時間で銅の金属超微粒子３の酸化皮膜を還元させる。そして、比較的高温に加熱することで、銅の金属超微粒子３の粒子径とその温度により定まる焼結時間以上の時間で焼結させる。この焼結の際の温度を上げることで速やかに焼結させることができる。   From this graph, the sintering speed of the copper ultrafine metal particles 3 has a speed difference of 100 times at temperatures of 200 ° C. and 300 ° C., and a speed difference of 100,000 times at temperatures of 100 ° C. and 300 ° C. Recognize. By utilizing the difference in the sintering speed depending on the temperature, the oxidation of the copper metal ultrafine particles 3 is performed at a relatively low temperature within a sintering time determined by the particle size of the copper metal ultrafine particles 3 and the temperature. Reduce the film. Then, by heating to a relatively high temperature, sintering is performed in a time longer than the sintering time determined by the particle diameter of the copper ultrafine metal particles 3 and the temperature. By increasing the temperature at the time of sintering, it can be rapidly sintered.

［第１の実施例］
本発明の第１の実施例として、多層の印刷配線板を製造する場合を説明する。第１の実施例では、表面に酸化皮膜が形成され易い銅の金属超微粒子を用い、図４に示す多層印刷配線板１を、以下の製造方法で製造する。 [First embodiment]
As a first embodiment of the present invention, a case where a multilayer printed wiring board is manufactured will be described. In the first embodiment, the multilayer printed wiring board 1 shown in FIG. 4 is manufactured by the following manufacturing method using copper metal ultrafine particles on which an oxide film is easily formed on the surface.

（１）先ず、直径２ｎｍから７０ｎｍの銅の金属超微粒子３を、エチルアルコールやトルエンなどの有機溶剤や水を主成分とする分散液中に分散させて保持した分散液３ａ（図１参照）を製造する。この銅の金属超微粒子３は、分散液３ａ中で厚さが１ｎｍ程度の酸化皮膜が形成された状態で存在する。その酸化皮膜が金属超微粒子３同士の焼結を妨げることで、分散液３ａ中で個々の金属超微粒子３が独立し良く分散された状態を保つことができる。   (1) First, a dispersion 3a in which copper metal ultrafine particles 3 having a diameter of 2 nm to 70 nm are dispersed and held in a dispersion mainly composed of an organic solvent such as ethyl alcohol or toluene, or water (see FIG. 1). Manufacturing. The copper ultrafine metal particles 3 exist in a state where an oxide film having a thickness of about 1 nm is formed in the dispersion 3a. Since the oxide film prevents the sintering of the metal ultrafine particles 3, the individual metal ultrafine particles 3 can be kept in a well dispersed state in the dispersion 3a.

（２）次に、２０μｍから６０μｍ程度の厚さが１０ｍｍから６００ｍｍ程度のガラスエポキシやポリイミド樹脂などから成る樹脂シート５上に、銅めっきによる配線パターン６と、樹脂シート５の表裏に形成された直径が５０μｍから２００μｍで厚さが１０μｍから５０μｍ程度の銅めっきの金属端子２と、その表裏の金属端子２を接続するように、樹脂シート５を貫通する直径が５０μｍから２００μｍの孔に銅めっきで金属柱７を形成する。   (2) Next, on the resin sheet 5 made of glass epoxy or polyimide resin having a thickness of about 20 to 60 μm and a thickness of about 10 to 600 mm, the wiring pattern 6 by copper plating and the front and back of the resin sheet 5 were formed. Copper plating is applied to holes having a diameter of 50 μm to 200 μm penetrating the resin sheet 5 so as to connect the copper-plated metal terminals 2 having a diameter of 50 μm to 200 μm and a thickness of about 10 μm to 50 μm and the metal terminals 2 on the front and back sides thereof. The metal pillar 7 is formed by this.

（３）次に、樹脂シート５を塩酸で洗浄することで、金属端子２の表面の酸化膜を溶解し除去する。しかし、この銅の金属端子２の表面は、その塩酸中に溶解している酸素成分で酸化されるため、厚さが１ｎｍ程度の薄い酸化皮膜が残る。   (3) Next, the resin sheet 5 is washed with hydrochloric acid to dissolve and remove the oxide film on the surface of the metal terminal 2. However, since the surface of the copper metal terminal 2 is oxidized by the oxygen component dissolved in the hydrochloric acid, a thin oxide film having a thickness of about 1 nm remains.

（４）次に、複数の樹脂シート５を、水素を含む大気圧プラズマあるいは原子状水素混入ガスなどの還元性ガス４（図１参照）に曝すことで、その樹脂シート５の金属端子２表面の有機物を還元し除去するとともに、金属端子２表面の１ｎｍ程度の薄い酸化皮膜を還元する。   (4) Next, the surface of the metal terminal 2 of the resin sheet 5 is exposed by exposing the plurality of resin sheets 5 to a reducing gas 4 (see FIG. 1) such as atmospheric pressure plasma containing hydrogen or an atomic hydrogen mixed gas. The organic substance is reduced and removed, and a thin oxide film of about 1 nm on the surface of the metal terminal 2 is reduced.

（５）次に、還元性ガス４の雰囲気中で、各樹脂シート５を赤外線ランプなどで約１００℃に加熱し、樹脂シート５の金属端子２上に、銅の金属超微粒子３を分散させた分散液３ａをディスペンサーあるいはインクジェット装置などの吐出装置８（図１参照）により吐出させ、吐出された分散液３ａを速やかに蒸発させ乾燥させる。そして、露出した銅の金属超微粒子３表面の酸化皮膜を還元性ガス４により還元させる。こうして、各樹脂シート５の直径が５０μｍから２００μｍの金属端子２上に、分散剤を含まない銅の金属超微粒子３のみによる厚さが２００ｎｍ以下の層状の銅の金属超微粒子層３ｂを形成する。   (5) Next, in the atmosphere of the reducing gas 4, each resin sheet 5 is heated to about 100 ° C. with an infrared lamp or the like to disperse the copper ultrafine metal particles 3 on the metal terminals 2 of the resin sheet 5. The dispersed liquid 3a is discharged by a discharge device 8 (see FIG. 1) such as a dispenser or an ink jet device, and the discharged dispersion 3a is quickly evaporated and dried. The exposed oxide film on the surface of the copper ultrafine metal particles 3 is reduced by the reducing gas 4. In this way, a layered copper metal ultrafine particle layer 3b having a thickness of 200 nm or less is formed on the metal terminal 2 having a diameter of 50 μm to 200 μm of each resin sheet 5 and containing only the copper metal ultrafine particles 3 not containing a dispersant. .

ここで、還元性ガス４の雰囲気中での、銅の金属超微粒子３の還元時間は、図３に従って、銅の金属超微粒子３の焼結以前の直径dにより定まる焼結時間以内の時間で還元処理をする。すなわち、樹脂シートを１００℃に加熱し、直径ｄが２ｎｍの場合は１秒以内で還元し、直径ｄが１０ｎｍでは１００秒以内、直径ｄが７０ｎｍでは２００００秒以内で還元する。あるいは、その直径dが２ｎｍの場合は、樹脂シート５を約１００℃に加熱し、その還元時間は約１秒以内で済ます。直径dが１０ｎｍの場合は、樹脂シート５を１５０℃に加熱し、その還元時間は約１０秒以内で済ます。直径dが７０ｎｍの場合は、樹脂シート５を２２０℃に加熱し、その還元時間は約１０秒以内で済ます。   Here, the reduction time of the copper metal ultrafine particles 3 in the atmosphere of the reducing gas 4 is a time within the sintering time determined by the diameter d before sintering of the copper metal ultrafine particles 3 according to FIG. Reduce. That is, the resin sheet is heated to 100 ° C. and reduced within 1 second when the diameter d is 2 nm, reduced within 100 seconds when the diameter d is 10 nm, and within 20000 seconds when the diameter d is 70 nm. Alternatively, when the diameter d is 2 nm, the resin sheet 5 is heated to about 100 ° C., and the reduction time is about 1 second. When the diameter d is 10 nm, the resin sheet 5 is heated to 150 ° C., and the reduction time is about 10 seconds or less. When the diameter d is 70 nm, the resin sheet 5 is heated to 220 ° C., and the reduction time is about 10 seconds or less.

樹脂シート５の金属端子２上において銅の金属超微粒子３の所定の還元時間を過ぎた後には、その樹脂シート５を室温以下に冷却された金属定板などに接するなどの冷却手段で冷却させる。これにより、銅の金属超微粒子３の焼結速度を低下させることができる。   After a predetermined reduction time of the copper ultrafine metal particles 3 has passed on the metal terminals 2 of the resin sheet 5, the resin sheet 5 is cooled by a cooling means such as coming into contact with a metal surface plate cooled to room temperature or lower. . Thereby, the sintering rate of the copper ultrafine metal particles 3 can be reduced.

また、この処理は、図１に示すように、銅の金属超微粒子３の直径dにより定まる焼結時間以内の時間で、数度繰り返すことで、数度に分けて銅の金属超微粒子３層を重ね、厚さが約０．５μｍから５μｍの銅の金属超微粒子層３ｂを形成しても良い。   In addition, as shown in FIG. 1, this treatment is repeated several times within a sintering time determined by the diameter d of the copper ultrafine metal particles 3, thereby dividing the copper ultrafine metal trilayers into several degrees. The copper ultrafine metal particle layer 3b having a thickness of about 0.5 μm to 5 μm may be formed.

（６）次に、還元性ガス４の雰囲気中で、あるいは、大気圧の水素ガス雰囲気中、窒素ガス中、あるいは真空中で、図４に示すように、各樹脂シート５を、銅の金属超微粒子３を配置した金属端子２同士を対向させて押し当てる。また、隣り合う樹脂シート５間にはプリプレグ９を挿入して積層し、約１７０℃に加熱し加圧しつつ３０分から１時間程度保持することで、プリプレグ９の樹脂成分を溶融させ、樹脂シート５同士をプリプレグ９で接着する。その積層工程において、同時に、隣り合う樹脂シート５の金属端子２同士を、その間の銅の金属超微粒子３を焼結させることで金属接合させる。樹脂シート５同士の積層温度１７０℃における、銅の金属超微粒子３の焼結時間は、銅の金属超微粒子３の直径により定まる焼結時間以上の時間をかけることで焼結させることができる。すなわち、その直径が２ｎｍの場合の焼結時間は１００分の１秒以上であり、直径が１０ｎｍの場合の焼結時間は１０秒以上であり、直径が７０ｎｍの場合の焼結時間は約１０００秒（２０分）以上である。   (6) Next, in the atmosphere of the reducing gas 4, or in the hydrogen gas atmosphere at atmospheric pressure, in the nitrogen gas, or in vacuum, as shown in FIG. The metal terminals 2 on which the ultrafine particles 3 are disposed are pressed against each other. Further, the prepreg 9 is inserted and laminated between the adjacent resin sheets 5, and the resin component of the prepreg 9 is melted by holding it for about 30 minutes to 1 hour while heating and pressing at about 170 ° C. They are bonded together with a prepreg 9. In the laminating step, metal terminals 2 of adjacent resin sheets 5 are simultaneously metal-bonded by sintering copper ultrafine particles 3 therebetween. The sintering time of the copper metal ultrafine particles 3 at a laminating temperature of 170 ° C. between the resin sheets 5 can be sintered by taking a time longer than the sintering time determined by the diameter of the copper metal ultrafine particles 3. That is, when the diameter is 2 nm, the sintering time is 1/100 second or more, when the diameter is 10 nm, the sintering time is 10 seconds or more, and when the diameter is 70 nm, the sintering time is about 1000 seconds. More than a second (20 minutes).

ここで、樹脂シート５をプリプレグ９により積層する温度と加工時間で、銅の金属超微粒子３が十分良く焼結するために、銅の金属超微粒子３の直径は７０ｎｍ以下であることが望ましい。他方、銅の金属超微粒子３の直径が２ｎｍ未満になると、その融点が３００℃以下になって溶融し易くなり、焼結速度が極めて速くなり、焼結を停止させる取り扱いが困難になるため、銅の金属超微粒子３の直径は２ｎｍ以上であることが望ましい。以上から、銅の金属超微粒子３の直径は２ｎｍから７０ｎｍまでの範囲が望ましい。   Here, the diameter of the copper ultrafine metal particles 3 is desirably 70 nm or less so that the copper ultrafine metal particles 3 are sufficiently sintered at the temperature and processing time for laminating the resin sheet 5 with the prepreg 9. On the other hand, when the diameter of the copper ultrafine metal particles 3 is less than 2 nm, the melting point thereof becomes 300 ° C. or less and the melting becomes easy, the sintering speed becomes extremely fast, and handling for stopping the sintering becomes difficult. The diameter of the copper metal ultrafine particles 3 is desirably 2 nm or more. From the above, the diameter of the copper ultrafine metal particles 3 is desirably in the range of 2 nm to 70 nm.

このようにして、対向し合う直径が５０μｍから２００μｍの金属端子２同士を銅の金属超微粒子３が焼結した厚さ５μｍ以下の金属層で、その直径が５０μｍ以上あり、結局、その直径が厚さの１０倍以上ある金属層を介して金属接合させることで、各層の配線パターン６が多層に電気接続する配線構造を有する多層印刷配線板１を得ることができる。   In this way, a metal layer having a thickness of 5 μm or less obtained by sintering the copper metal ultrafine particles 3 between the metal terminals 2 having opposing diameters of 50 μm to 200 μm, the diameter is 50 μm or more. The multilayer printed wiring board 1 having a wiring structure in which the wiring patterns 6 of each layer are electrically connected in multiple layers can be obtained by metal bonding through a metal layer having a thickness 10 times or more.

ここで、本実施例の金属端子２は、厚さが１０μｍ程度の銅めっきの金属端子のパターンの上に、銅の金属超微粒子を厚さ１０μｍまで設置し焼結することで形成しても良い。その場合は、２００℃に加熱した金属端子のパターンの上に粒径が２ｎｍの銅の金属超微粒子３の分散液をインクジェット装置などの高速吐出装置により１００分の１秒で吐出する。分散液が２００℃の金属端子に着弾して蒸発し、その金属超微粒子３の表面の酸化皮膜が還元されると、この粒径では、約１００分の１秒で焼結する。そのため、５０分の１秒間隔で金属端子のパターン上に重ねて分散液を吐出させ、銅の金属超微粒子３の層を焼結させた金属層の厚さを増すことで１０μｍの厚さまでに金属層を重ねた銅の金属端子２を形成し、それを用いることもできる。   Here, the metal terminal 2 of the present embodiment may be formed by placing and sintering copper metal ultrafine particles to a thickness of 10 μm on a copper-plated metal terminal pattern having a thickness of about 10 μm. good. In that case, a dispersion of copper ultrafine metal particles 3 having a particle diameter of 2 nm is discharged on a metal terminal pattern heated to 200 ° C. in 1/100 second by a high-speed discharge device such as an inkjet device. When the dispersion reaches the metal terminal at 200 ° C. and evaporates, and the oxide film on the surface of the metal ultrafine particles 3 is reduced, the particle size sinters in about 1/100 second. Therefore, the dispersion liquid is discharged on the metal terminal pattern at intervals of 1/50 second, and the thickness of the metal layer obtained by sintering the layer of copper ultrafine metal particles 3 is increased to a thickness of 10 μm. It is also possible to form a copper metal terminal 2 on which metal layers are stacked and use it.

また、本実施例では金属超微粒子３の金属として銅を用いたが、銅を主成分とするベリリウムやマンガンや金や亜鉛や錫などの金属との合金、あるいは、銅を主成分とするガリウムやシリコンやゲルマニウなどとの合金等の、融点を銅の融点より低くした銅の合金の金属超微粒子３を用いることもできる。   In this embodiment, copper is used as the metal of the metal ultrafine particles 3, but beryllium, which is mainly composed of copper, alloy with metals such as manganese, gold, zinc, tin, or gallium, which is mainly composed of copper. It is also possible to use ultrafine metal particles 3 of a copper alloy whose melting point is lower than that of copper, such as an alloy with silicon, germanium, or the like.

［第１の実施例の効果］
本実施例は、従来、層間の配線接続をビアホールに銅めっきを形成することで得ていた多層印刷配線板を、その銅めっき工程を用いずに、銅の金属超微粒子３を用いることで、銅の配線パターン６と銅めっきによる金属柱７と金属端子２を形成した樹脂シート５を重ね合わせ、対向し合う金属端子２同士を銅の金属超微粒子３を用いて接合した。すなわち、本実施例は、銅の金属超微粒子３がその融点よりも十分低い温度で焼結する現象を利用し、印刷配線板の樹脂シート５を積層する条件において、各樹脂シート５に形成した金属端子２同士を、その間に挟み込んだ銅の金属超微粒子３を焼結させて金属接合することで、多層印刷配線板１の各層の配線パターン６が電気接続された多層の電気配線構造を有する多層印刷配線板１を短時間に得ることができる効果がある。これにより、印刷配線板１の製造コストを低減できる効果がある。ここで、従来、この種の効果を有する印刷配線板としては、銀ペーストを利用して樹脂シートの配線パターンの層間を電気接続した印刷配線板が知られていた。これに対し、本実施例は、従来の印刷配線板の銀ペーストを銅の金属超微粒子３による層に置き換えて製造することで、従来の銀ペーストを用いた電気接続では信頼性が低かった問題を解決している。また、印刷配線板が湿度環境に曝される場合に、それに用いられている銀ペーストの銀がマイグレーションすることにより、その配線間がショートする故障が生じ、信頼性が低いという問題を解決している。本実施例は、これにより、多層印刷配線板１の信頼性を向上させ、車載向けなどの高い安全性を求める情報家電にもこの多層印刷配線板１を使えるようにした産業上の効果がある。 [Effect of the first embodiment]
In this example, a multilayer printed wiring board that has been conventionally obtained by forming copper plating in via holes for wiring connection between layers is obtained by using copper metal ultrafine particles 3 without using the copper plating step. The copper wiring pattern 6, the metal column 7 formed by copper plating, and the resin sheet 5 on which the metal terminal 2 was formed were superposed, and the metal terminals 2 facing each other were bonded together using copper metal ultrafine particles 3. That is, in this example, the copper metal ultrafine particles 3 were formed on each resin sheet 5 under the condition of laminating the resin sheets 5 of the printed wiring board using a phenomenon that the copper ultrafine particles 3 were sintered at a temperature sufficiently lower than the melting point. The metal terminals 2 are sintered and metal bonded by sintering copper ultrafine particles 3 sandwiched therebetween, thereby having a multilayer electrical wiring structure in which the wiring patterns 6 of each layer of the multilayer printed wiring board 1 are electrically connected. There is an effect that the multilayer printed wiring board 1 can be obtained in a short time. Thereby, there exists an effect which can reduce the manufacturing cost of the printed wiring board 1. FIG. Heretofore, as a printed wiring board having this type of effect, a printed wiring board in which layers of a resin sheet wiring pattern are electrically connected using a silver paste has been known. On the other hand, in this example, the problem was that the electrical connection using the conventional silver paste had low reliability by replacing the silver paste of the conventional printed wiring board with the layer of the copper ultrafine metal particles 3. Has solved. In addition, when the printed wiring board is exposed to a humidity environment, the silver paste silver used in the printed circuit board migrates, causing a failure that causes a short circuit between the wiring and solving the problem of low reliability. Yes. In this embodiment, the reliability of the multilayer printed wiring board 1 is thereby improved, and there is an industrial effect in which the multilayer printed wiring board 1 can also be used for information home appliances that require high safety such as for vehicles. .

［第２の実施例］
第２の実施例が第１の実施例と異なる点は、金属超微粒子３として、適切な粒径の銅あるいは銅合金の金属超微粒子３と、それより粒径が小さいが焼結時間が同じ程度である他の金属あるいは合金の金属超微粒子３’（図６に示す）を混在させて用いる点にある。それら異なる種類の金属超微粒子を分散液３ａに分散させ、図１、図２で説明したように、その分散液３ａを第１の金属端子２ａに吐出させ蒸発させることで、異種の金属あるいは合金から構成される金属超微粒子層３ｂを形成する。次に、還元性ガスによって有機物および酸化皮膜を還元、除去した後、第１の金属端子２ａに第２の金属端子２ｂを重ね合わせ、金属超微粒子層３ｂを焼結させることにより第１の金属端子２ａと第２の金属端子２ｂを金属接合させる。 [Second Embodiment]
The second embodiment is different from the first embodiment in that the metal ultrafine particles 3 are the same as the ultrafine metal particles 3 of copper or copper alloy having an appropriate particle size, but the particle size is smaller than that but the sintering time is the same. The metal ultrafine particles 3 ′ (shown in FIG. 6) of other metals or alloys having a degree of mixing are used. Dispersing these different types of ultrafine metal particles in the dispersion 3a, and discharging and evaporating the dispersion 3a onto the first metal terminal 2a as described with reference to FIGS. 1 and 2, thereby dissimilar metals or alloys. An ultrafine metal particle layer 3b composed of Next, after reducing and removing the organic substance and the oxide film with the reducing gas, the second metal terminal 2b is overlaid on the first metal terminal 2a, and the metal ultrafine particle layer 3b is sintered to thereby sinter the first metal. The terminal 2a and the second metal terminal 2b are metal-bonded.

これにより、金属超微粒子層３ｂが焼結して得られた金属層の密度が高くなり、より強固な金属接合が得られる効果がある。   Thereby, the density of the metal layer obtained by sintering the metal ultrafine particle layer 3b is increased, and there is an effect that stronger metal bonding can be obtained.

以下、第２の実施例における金属超微粒子の構成について詳しく説明する。   Hereinafter, the configuration of the ultrafine metal particles in the second embodiment will be described in detail.

第１の金属超微粒子３として、第１の実施例と同様な粒子径の銅の金属超微粒子を用いる。そして、第２の金属超微粒子として、チタンの金属超微粒子を用いる。チタンは銅よりも更に酸化され易い金属であるが、酸素の固容量が大きいため酸化皮膜の酸素がチタン中に拡散して消滅し易い。このため、銅の金属超微粒子３同士の接合面に酸化皮膜が少し残っている場合も、その酸化皮膜の酸素をチタン母材中に拡散することで酸化皮膜を消滅させ、金属超微粒子の焼結を助ける。チタンの焼結速度も、式（１）と式（２）で計算する。その計算のパラメータは、チタンの金属超微粒子の場合は、Ｎ＝(４π／３)ｄ３／(０．０１７５ｎｍ３)であり、気体と接する表面自由エネルギーＥは１６５０erg/cm２である。また、チタンの粒界拡散係数は詳しいデータが無かったが、銅の場合と同様に、体積拡散係数の半分程度であると考えられ、その拡散係数の振動数因子Ｄｏは、１．４cm２／sec、粒界拡散の活性化エネルギーＱは、１５０kJ／mol程度と考えられる。このパラメータで計算したチタンの焼結時間、焼結温度と粒径の関係を図５のグラフに示す。 As the first metal ultrafine particles 3, copper metal ultrafine particles having the same particle diameter as in the first embodiment are used. As the second metal ultrafine particles, titanium metal ultrafine particles are used. Titanium is a metal that is more easily oxidized than copper. However, since the solid volume of oxygen is large, oxygen in the oxide film is easily diffused into titanium and disappears. For this reason, even if a little oxide film remains on the joint surface between the copper metal ultrafine particles 3, the oxide film disappears by diffusing oxygen in the oxide film into the titanium base material, and the metal ultrafine particles are baked. Help tie. The sintering rate of titanium is also calculated by the equations (1) and (2). The parameter of the calculation is N = (4π / 3) d 3 /(0.0175 nm 3 ) in the case of titanium ultrafine particles, and the surface free energy E in contact with the gas is 1650 erg / cm 2 . Further, although there is no detailed data on the grain boundary diffusion coefficient of titanium, it is considered to be about half of the volume diffusion coefficient as in the case of copper, and the frequency factor Do of the diffusion coefficient is 1.4 cm 2 / sec, the activation energy Q of grain boundary diffusion is considered to be about 150 kJ / mol. The graph of FIG. 5 shows the relationship between the sintering time, sintering temperature, and particle size of titanium calculated with these parameters.

図５のグラフから、チタンの金属超微粒子の焼結速度は、プリプレグ９（図４）を積層すると同時に金属超微粒子を焼結させる温度の１７０℃においては、粒子の直径dが１０ｎｍの銅の金属超微粒子３の焼結速度と、粒子の直径dが０．５ｎｍのチタンの金属超微粒子の焼結速度が同じである。同様に、２０ｎｍの銅の金属超微粒子３と１ｎｍのチタンの金属超微粒子の焼結速度が同じである。結局、銅の金属超微粒子３と、その２０分の１の直径のチタンの金属超微粒子の焼結速度が同等である。このため、図６に示すように、直径が１０ｎｍの銅の第１の金属超微粒子３と、その直径の約４分の１の直径のチタンの第２の金属超微粒子３’を、それぞれ同じ数づつ混ぜ合わせることで、銅の金属超微粒子３が最密の面心立方格子状に充填された隙間に、ちょうど収納される直径のチタンの金属超微粒子３‘を混ぜ合わせるようにする。あるいは、直径が１０ｎｍの銅の金属超微粒子３の直径の２０分の１の０．５ｎｍの直径のチタンの金属超微粒子３’は焼結温度も銅の金属超微粒子３と同じ程度であるが、それを、銅の超微粒子３の体積に対して、０．２６倍から０．５倍の体積の分量を混合する。この金属超微粒子の分散液３ａを吐出させることで金属超微粒子層３ｂを形成し、第１の金属端子２ａと第２の金属端子２ｂの間で焼結させることで、第１、第２の金属端子２ａ、２ｂを金属接合する。特に、銅の金属超微粒子３の２０分の１で焼結温度も同じ程度のチタンの金属超微粒子３’を、銅の超微粒子３の体積に対して、０．２６倍の体積量で混合する場合は、金属超微粒子層３ｂの焼結前の充填率を、銅の金属超微粒子のみの場合では７４％の充填率であったのを９３％にまで高められることで、焼結で得られる金属層が緻密に形成できる効果がある。   From the graph of FIG. 5, the sintering speed of the ultrafine metal particles of titanium is as follows. At 170 ° C., the temperature at which the ultrafine metal particles are sintered at the same time as the prepreg 9 (FIG. 4) is laminated, the diameter d of copper is 10 nm. The sintering speed of the ultrafine metal particles 3 is the same as that of titanium ultrafine metal particles having a diameter d of 0.5 nm. Similarly, the sintering speeds of the 20 nm copper ultrafine metal particles 3 and the 1 nm titanium ultrafine metal particles are the same. After all, the sintering speed of copper ultrafine metal particles 3 is equal to that of titanium ultrafine metal particles having a diameter of 1/20. Therefore, as shown in FIG. 6, the first metal ultrafine particles 3 of copper having a diameter of 10 nm and the second metal ultrafine particles 3 ′ of titanium having a diameter of about a quarter of the diameter are the same. By mixing a few, the ultrafine metal particles 3 ′ having a diameter just accommodated in the gap filled with the ultrafine copper particle 3 in a close-packed face-centered cubic lattice are mixed. Alternatively, the titanium metal ultrafine particles 3 ′ having a diameter of 0.5 nm, which is 1/20 of the diameter of the copper metal ultrafine particles 3 having a diameter of 10 nm, have a sintering temperature similar to that of the copper metal ultrafine particles 3. Then, the volume of 0.26 times to 0.5 times the volume of the ultrafine copper particles 3 is mixed. By discharging the dispersion liquid 3a of the metal ultrafine particles, the metal ultrafine particle layer 3b is formed and sintered between the first metal terminal 2a and the second metal terminal 2b, whereby the first and second metal fine particle layers 3b are formed. The metal terminals 2a and 2b are metal-bonded. In particular, the titanium metal ultrafine particles 3 ′, which is 1/20 of the copper metal ultrafine particles 3 and has the same sintering temperature, is mixed in a volume of 0.26 times the volume of the copper ultrafine particles 3. In this case, the filling rate before sintering of the metal ultrafine particle layer 3b can be increased to 93% from the 74% filling rate in the case of copper ultrafine particles alone, and thus obtained by sintering. There is an effect that the metal layer to be formed can be densely formed.

なお、本実施例は、銅の金属超微粒子３とチタンの金属超微粒子３’を混ぜ合わせた金属超微粒子層３ｂにより２つの金属端子同士を接合する場合を示したが、同様に、１７０℃において焼結速度が同等で大きさの異なる銅合金の金属超微粒子と銅の金属超微粒子３とを混ぜ合わせた金属超微粒子層３ｂにより２つの金属端子同士を接合することも可能である。   In addition, although the present Example showed the case where two metal terminals were joined by the metal ultrafine particle layer 3b which mixed the metal ultrafine particle 3 of copper, and the metal ultrafine particle 3 'of titanium, it is 170 degreeC similarly. It is also possible to join the two metal terminals by the metal ultrafine particle layer 3b in which the ultrafine particles of copper alloys having the same sintering speed and different sizes and the ultrafine metal particles 3 of copper are mixed.

本実施例の他の変形例として、直径が２０ｎｍ程度の銅の金属超微粒子３と、その直径が２０倍の０．４μｍから１μｍ程度の銅の金属微粒子とを混合した金属超微粒子層３ｂを第１の金属端子２ａに設置して用いても良い。すなわち、その銅粒子の体積に対して０．２６倍から０．５倍の銅の金属超微粒子３を混合した金属粒子混合体を、分散液中３ａで良く撹拌し、その分散液３ａを第１の金属端子２ａに吐出し、分散液３ａを速やかに乾燥させ、また、金属超微粒子３の酸化皮膜を還元性ガス４で還元させることで、０．４μｍから１μｍの厚さの金属粒子と金属超微粒子３が混合された金属超微粒子層３ｂを形成する。その後に、その金属超微粒子層３ｂの上に加熱した第２の金属端子２ｂを押し当てることで金属超微粒子層３ｂを焼結させ、両金属端子２を金属接合させることができる。また、この金属超微粒子層３ｂの他の形成方法としては、先ず、金属端子２ａ上に金属超微粒子３のみの分散液３ａを吐出し金属超微粒子層３ｂを形成し、次に、その層の上に、別に用意した分散液３ａに分散した０．４μｍから１μｍの直径の金属微粒子を、単層で設置されるように分散液３ａを先に形成した金属超微粒子層３ｂ上に吐出し乾燥させ、また、還元性ガス４で還元して金属微粒子を設置し、その次に、その金属微粒子の単層を覆うように、金属超微粒子３の分散液３ａを吐出することで金属超微粒子層３ｂを形成しても良い。なお、この、異なる直径の金属微粒子を混合した金属超微粒子層３ｂを焼結して得た金属層には有機物が混入しないので、従来の金属ペーストにより形成された金属層とは異なり、その金属接合の強度が強い効果がある。   As another modification of the present embodiment, a metal ultrafine particle layer 3b in which copper metal ultrafine particles 3 having a diameter of about 20 nm and copper metal fine particles having a diameter of 20 to about 0.4 μm to about 1 μm are mixed is provided. You may install and use in the 1st metal terminal 2a. That is, a metal particle mixture obtained by mixing copper ultrafine particles 3 of 0.26 times to 0.5 times the volume of the copper particles is well stirred in the dispersion 3a, and the dispersion 3a 1 to the metal terminal 2a, the dispersion 3a is quickly dried, and the oxide film of the metal ultrafine particles 3 is reduced with the reducing gas 4, so that the metal particles having a thickness of 0.4 μm to 1 μm are obtained. The metal ultrafine particle layer 3b in which the metal ultrafine particles 3 are mixed is formed. After that, by pressing the heated second metal terminal 2b on the metal ultrafine particle layer 3b, the metal ultrafine particle layer 3b can be sintered, and the metal terminals 2 can be metal-bonded. As another method for forming the metal ultrafine particle layer 3b, first, the dispersion 3a of only the metal ultrafine particles 3 is discharged on the metal terminal 2a to form the metal ultrafine particle layer 3b. On the top, metal fine particles having a diameter of 0.4 μm to 1 μm dispersed in a separately prepared dispersion liquid 3a are discharged onto the metal ultrafine particle layer 3b previously formed so that the dispersion liquid 3a is placed in a single layer and dried. In addition, the metal ultrafine particle layer is formed by discharging the dispersion 3a of the metal ultrafine particle 3 so as to cover the single layer of the metal fine particle after being reduced by the reducing gas 4 and installing the metal fine particle. 3b may be formed. Since the organic layer is not mixed in the metal layer obtained by sintering the metal ultrafine particle layer 3b in which the metal fine particles having different diameters are mixed, the metal layer is different from the metal layer formed by the conventional metal paste. There is an effect of strong bonding strength.

［第２の実施例の効果］
大きさが４倍から２０倍程度異なる第１の金属超微粒子あるいは金属微粒子と、第２の金属超微粒子を混ぜ合わせた金属超微粒子層３ｂにより、直径が大きい方の金属超微粒子あるいは金属微粒子が最密に設置された隙間にちょうど収納される直径の小さな金属超微粒子が設置され、充填率が高められ焼結粒子間の隙間を小さくした金属超微粒子層３ｂが得られ、これを焼結すると容易に緻密な金属層が得られる効果がある。この金属超微粒子層３ｂにより第１の金属端子２ａと第２の金属端子２ｂを金属接合させることで金属超微粒子層３ｂを焼結して得た金属層を緻密な構造に形成でき、その金属接合の強度を高めることができる。 [Effect of the second embodiment]
Due to the metal ultrafine particle layer 3b in which the first metal ultrafine particles or metal fine particles differing in size by about 4 to 20 times and the second metal ultrafine particles are mixed, the metal ultrafine particles or metal fine particles having a larger diameter are obtained. When the ultrafine metal particles 3b having a small diameter that are just stored in the closely-spaced gaps are installed, the ultrafine metal particle layer 3b having a high filling rate and a small gap between the sintered particles is obtained. There is an effect that a dense metal layer can be easily obtained. The metal layer obtained by sintering the metal ultrafine particle layer 3b by metal-bonding the first metal terminal 2a and the second metal terminal 2b with the metal ultrafine particle layer 3b can be formed into a dense structure. Bonding strength can be increased.

［第３の実施例］
第３の実施例は、図７に示すように、表面が酸化され易い銅やニッケルなどの金属端子２を形成した複数の半導体チップ１２を製造し、隣接する半導体チップ１２が縦横の長さが１０μｍ□程度、すなわち、直径が１０μｍ程度の銅の金属端子２同士をそれと同じ材質の銅の金属超微粒子３を焼結させて得た厚さが１μｍ以下の金属層により接合することで複数の半導体チップ１２をマルチチップ型に構成した半導体装置１３である。 [Third embodiment]
In the third embodiment, as shown in FIG. 7, a plurality of semiconductor chips 12 having metal terminals 2 such as copper and nickel whose surfaces are easily oxidized are manufactured, and the adjacent semiconductor chips 12 have vertical and horizontal lengths. A plurality of copper metal terminals 2 having a thickness of about 10 μm □, that is, a diameter of about 10 μm, are joined by a metal layer having a thickness of 1 μm or less obtained by sintering copper metal ultrafine particles 3 of the same material. This is a semiconductor device 13 in which the semiconductor chip 12 is configured in a multi-chip type.

ここで、半導体チップ１２は、厚さが５０μｍから１００μｍ程度のシリコンからなる半導体基板１４を含んでいる。半導体基板１４の一方の表面（以下、「表面」と言う）には、複数の電極を有する機能素子（デバイス）１５が形成されている。機能素子１５の側方には、半導体基板１４をその厚さ方向に貫通する孔に銅の金属柱７が形成されている。半導体基板１４と金属柱７の間の孔の壁面には酸化シリコンからなる絶縁膜１６が形成されている。また、半導体基板１４の表面には、酸化シリコンから成り、開口１７を有するハードマスク１８が形成されている。半導体基板１４を垂直に見下ろす平面視において、開口１７内には機能素子１５の電極が存在しており、開口１７内の電極と金属柱７は連続した銅の配線パターン６で電気接続されている。絶縁膜１６上、開口１７内、および、開口１７と金属柱７の間のハードマスク１８上を含む所定の領域には、タンタルナイライド（ＴａＮ）やチタンナイライド（ＴｉＮ）からなる連続した拡散防止膜（図示せず）が形成されている。   Here, the semiconductor chip 12 includes a semiconductor substrate 14 made of silicon having a thickness of about 50 μm to 100 μm. A functional element (device) 15 having a plurality of electrodes is formed on one surface (hereinafter referred to as “surface”) of the semiconductor substrate 14. On the side of the functional element 15, a copper metal column 7 is formed in a hole penetrating the semiconductor substrate 14 in the thickness direction. An insulating film 16 made of silicon oxide is formed on the wall surface of the hole between the semiconductor substrate 14 and the metal pillar 7. A hard mask 18 made of silicon oxide and having an opening 17 is formed on the surface of the semiconductor substrate 14. In a plan view of the semiconductor substrate 14 looking down vertically, the electrode of the functional element 15 exists in the opening 17, and the electrode in the opening 17 and the metal pillar 7 are electrically connected by a continuous copper wiring pattern 6. . In a predetermined region including the insulating film 16, the opening 17, and the hard mask 18 between the opening 17 and the metal pillar 7, continuous diffusion of tantalum nitride (TaN) or titanium nitride (TiN) is performed. A prevention film (not shown) is formed.

半導体基板１４の反対面（以下[裏面]と言う。）には、金属柱７と一体で、裏面から突出した銅の金属端子２が形成されている。   On the opposite surface (hereinafter referred to as “back surface”) of the semiconductor substrate 14, a copper metal terminal 2 is formed integrally with the metal pillar 7 and protruding from the back surface.

以下、本発明の第３の実施例である半導体装置１３の製造方法を説明する。   A method for manufacturing the semiconductor device 13 according to the third embodiment of the present invention will be described below.

（１）先ず、第１の実施例と同様に、直径２ｎｍから７０ｎｍの銅の金属超微粒子３を分散させて保持した分散液３ａを製造する。以下では、直径５ｎｍの銅の金属超微粒子３の場合について説明する。また、この分散液３ａは、直径５ｎｍの銅の金属超微粒子の重量２６から５０に対して、直径１００ｎｍの銅の超微粒子の重量を１００で混合した分散液を用いても良い。この場合は、第２の実施例と同様に、直径１００ｎｍの銅の金属超微粒子３の焼結は遅いが、それを直径５ｎｍの銅の金属超微粒子３が速やかに焼結することで接合するため、これにより、緻密な金属接合をすることができる。   (1) First, in the same manner as in the first embodiment, a dispersion 3a in which copper metal ultrafine particles 3 having a diameter of 2 nm to 70 nm are dispersed and held is manufactured. Below, the case of the ultrafine metal particles 3 of copper having a diameter of 5 nm will be described. The dispersion 3a may be a dispersion in which the weight of copper ultrafine particles having a diameter of 100 nm is mixed with the weight 26 to 50 of copper metal ultrafine particles having a diameter of 5 nm. In this case, as in the second embodiment, the sintering of the copper metal ultrafine particles 3 having a diameter of 100 nm is slow, but the copper metal ultrafine particles 3 having a diameter of 5 nm are rapidly sintered to join. Therefore, this makes it possible to form a dense metal joint.

（２）次に、半導体チップ１２の裏面の銅の金属端子２を塩酸で洗浄することで、金属端子２の表面の酸化膜を溶解し除去する。しかし、この銅の金属端子２の表面は、その塩酸中に溶解している酸素成分で酸化されるため、厚さが１ｎｍ程度の薄い酸化皮膜が残る。   (2) Next, the copper metal terminal 2 on the back surface of the semiconductor chip 12 is washed with hydrochloric acid to dissolve and remove the oxide film on the surface of the metal terminal 2. However, since the surface of the copper metal terminal 2 is oxidized by the oxygen component dissolved in the hydrochloric acid, a thin oxide film having a thickness of about 1 nm remains.

（３）次に、この半導体チップ１２を、還元性ガス４に曝すことで、半導体チップ１２裏面における金属端子２表面の有機物を還元し除去するとともに、その金属端子２表面の１ｎｍ程度の薄い酸化皮膜を還元する。ここで、この還元性ガス４は、大気圧で無くとも、例えば１００Ｐａ程度に減圧した雰囲気中で、原子状水素を生成して成る還元性ガス４を用いることができる。   (3) Next, the semiconductor chip 12 is exposed to the reducing gas 4 to reduce and remove organic substances on the surface of the metal terminal 2 on the back surface of the semiconductor chip 12, and the surface of the metal terminal 2 is thinly oxidized by about 1 nm. Reduce the film. Here, as the reducing gas 4, the reducing gas 4 produced by generating atomic hydrogen in an atmosphere reduced to, for example, about 100 Pa can be used even if it is not atmospheric pressure.

（４）次に、還元性ガス４の雰囲気中で、半導体チップ１２を約１００℃に加熱し、半導体チップ１２の裏面の金属端子２上に、銅の金属超微粒子３を分散させた分散液３ａをディスペンサーあるいはインクジェット装置などの吐出装置８により吐出させ、吐出された分散液３ａを速やかに蒸発させ乾燥させる。そして、露出した銅の金属超微粒子３表面の酸化皮膜を還元性ガス４により還元させる。こうして、半導体チップ１２の裏面の直径１０μｍの金属端子２上に、分散剤を含まない銅の金属超微粒子３のみによる、厚さが１μｍ以下の２００ｎｍ程度で、厚さに直角な方向の直径が２μｍ以上の、すなわち厚さの１０倍以上の銅の金属超微粒子層３ｂを形成する。銅の金属超微粒子３の直径は５ｎｍ程度とする。ここで、還元性ガス４の雰囲気中での、銅の金属超微粒子３の還元時間は、１０秒以内に還元する。   (4) Next, a dispersion liquid in which the semiconductor chip 12 is heated to about 100 ° C. in the atmosphere of the reducing gas 4 and the copper metal ultrafine particles 3 are dispersed on the metal terminals 2 on the back surface of the semiconductor chip 12. 3a is discharged by a discharge device 8 such as a dispenser or an ink jet device, and the discharged dispersion 3a is quickly evaporated and dried. The exposed oxide film on the surface of the copper ultrafine metal particles 3 is reduced by the reducing gas 4. Thus, on the metal terminal 2 having a diameter of 10 μm on the back surface of the semiconductor chip 12, the diameter in the direction perpendicular to the thickness is about 200 nm with a thickness of 1 μm or less, only by the copper ultrafine particles 3 not containing a dispersant. A copper ultrafine particle layer 3b of 2 μm or more, that is, 10 times or more the thickness is formed. The diameter of the copper metal ultrafine particles 3 is about 5 nm. Here, the reduction time of the copper ultrafine metal particles 3 in the atmosphere of the reducing gas 4 is reduced within 10 seconds.

（５）次に、図７に示すように、還元性ガス４の雰囲気中で、あるいは、大気圧の水素ガス雰囲気中、窒素ガス中、あるいは真空中で、各半導体チップ１２を、その銅の金属超微粒子３の還元後に数十秒以内の時間で重ね合わせ、半導体チップ１２裏面の、銅の金属超微粒子３を形成した金属端子２を、下側の半導体チップ１２の表面の銅の金属端子２に押し当て、約１７０℃に加熱し加圧しつつ１秒以上保持する。これにより、隣り合う半導体チップ１２の銅の金属端子２同士を、その間の銅の金属超微粒子３を焼結させることで金属接合させる。１７０℃、その他の温度における、その他の直径の銅の金属超微粒子３の焼結時間は、第１の実施例と同様に、銅の金属超微粒子３の直径により定まる焼結時間以上の時間をかけることで焼結させることができる。   (5) Next, as shown in FIG. 7, each semiconductor chip 12 is made of its copper in an atmosphere of reducing gas 4 or in an atmosphere of hydrogen gas, nitrogen gas or vacuum. After the reduction of the ultrafine metal particles 3, the metal terminals 2 on which the copper ultrafine metal particles 3 are formed on the back surface of the semiconductor chip 12 are overlapped with each other within a time of several tens of seconds, and the copper metal terminals on the surface of the lower semiconductor chip 12. 2 and heated to about 170 ° C. and kept pressurized for 1 second or more. As a result, the copper metal terminals 2 of the adjacent semiconductor chips 12 are metal-bonded by sintering the copper metal ultrafine particles 3 therebetween. The sintering time of the copper ultrafine metal particles 3 of other diameters at 170 ° C. and other temperatures is equal to or longer than the sintering time determined by the diameter of the ultrafine copper metal particles 3 as in the first embodiment. It can be sintered by applying.

また、最下層の半導体チップ１２は、有機樹脂基板あるいはセラミックス基板のインタポーザ２０の表面に重ね、その表面の銅の金属端子２に、最下層の半導体チップ１２裏面の銅の金属超微粒子層３ｂを焼結させることで、半導体チップ１２の金属端子２とインタポーザ２０の金属端子２１を金属接合させる。インタポーザ２０の裏面にははんだボール２２を設置する。   The lowermost semiconductor chip 12 is overlaid on the surface of the organic resin substrate or ceramic substrate interposer 20, and the copper metal ultrafine particle layer 3 b on the rear surface of the lowermost semiconductor chip 12 is formed on the copper metal terminal 2 on the surface. By sintering, the metal terminal 2 of the semiconductor chip 12 and the metal terminal 21 of the interposer 20 are metal-bonded. Solder balls 22 are installed on the back surface of the interposer 20.

このようにして、複数の半導体チップ１２が銅の金属端子２同士を銅の金属超微粒子３の層を介して金属接合することで、複数の半導体チップ１２が多層に重ねられた配線構造を有する半導体装置１３を得る。   In this way, the plurality of semiconductor chips 12 have a wiring structure in which the plurality of semiconductor chips 12 are stacked in multiple layers by metal bonding the copper metal terminals 2 to each other through the layer of the copper metal ultrafine particles 3. A semiconductor device 13 is obtained.

なお、本実施例で、銅の金属超微粒子３のかわりに、銅を主体とする、例えば銅原子を５０原子％以上含む銅合金の金属超微粒子３を用いても良い。ここで、銅を５０原子％以上含む銅合金の融点は、ほとんど全て融点が５００℃以上ある。例えば、ＰとＣｕの合金では、Ｐが２５原子％以下の場合に、その沸点より低い温度で溶融する固体になり、そこで、Ｐが約１６原子％のＣｕ−Ｐ共晶合金の融点は約７２０℃ある。Ａｌ−Ｃｕ合金では、Ａｌの原子％が約８３％のＣｕ−Ａｌ共晶合金でも、その融点が５４８℃であり、Ｃｕ−Ｓｂ合金では、Ｓｂの原子％が約６３％のＣｕ−Ｓｂ共晶合金でも、その融点が約５３０℃である。Ｃｕ−Ｓｎ合金では、Ｓｎを５０原子％有するＣｕ−Ｓｎ合金の融点が約６２０℃であり、Ｃｕ−Ｚｎ合金では、Ｚｎを５０原子％有するＣｕ−Ｚｎ合金の融点が約８７０℃である。また、Ｃｕ−Ｂｉ合金では、Ｂｉを５０原子％有するＣｕ−Ｂｉ合金の融点が約８３０℃であり、Ｃｕ−Ｌａ合金では、Ｌａを５０原子％有するＣｕ−Ｌａ合金の融点が約７００℃である。このように、銅を５０原子％以上含む銅合金の融点は、ほとんど全て融点が５００℃以上あるため、従来は、銅あるいはこれらの銅合金の金属層により半導体チップ１２の銅の金属端子２同士を接合しようとすると、これらの金属層を溶融する５００℃以上の温度で半導体チップ１２を処理することが半導体チップ１２の機能素子１５の特性を変えてしまうため、それらの銅合金によっては半導体装置１３を製造できなかった。   In this embodiment, instead of the copper metal ultrafine particles 3, copper alloy metal ultrafine particles 3 mainly containing copper, for example, containing 50 atomic% or more of copper atoms may be used. Here, almost all of the melting points of copper alloys containing 50 atomic% or more of copper are 500 ° C. or more. For example, in an alloy of P and Cu, when P is 25 atomic% or less, it becomes a solid that melts at a temperature lower than its boiling point. Therefore, the melting point of a Cu-P eutectic alloy having P of about 16 atomic% is about 720 ° C. In the case of an Al—Cu alloy, a Cu—Al eutectic alloy in which the atomic percent of Al is about 83% is 548 ° C., and in the Cu—Sb alloy, the Cu—Sb alloy in which the atomic percent of Sb is about 63%. Even a crystal alloy has a melting point of about 530 ° C. In the Cu—Sn alloy, the melting point of the Cu—Sn alloy having 50 atomic% of Sn is about 620 ° C., and in the Cu—Zn alloy, the melting point of the Cu—Zn alloy having 50 atomic% of Zn is about 870 ° C. In the Cu—Bi alloy, the melting point of the Cu—Bi alloy having 50 atomic% Bi is about 830 ° C., and in the Cu—La alloy, the melting point of the Cu—La alloy having 50 atomic% La is about 700 ° C. is there. As described above, since the melting points of copper alloys containing 50 atomic% or more of copper are almost all melting points of 500 ° C. or higher, conventionally, copper or copper metal terminals 2 of the semiconductor chip 12 are made of copper or a metal layer of these copper alloys. If the semiconductor chip 12 is processed at a temperature of 500 ° C. or higher at which these metal layers are melted, the characteristics of the functional element 15 of the semiconductor chip 12 will be changed. 13 could not be produced.

本実施例では、銅原子を５０原子％以上含む銅合金の金属超微粒子３を用い、粒子の直径が２ｎｍから７０ｎｍの金属超微粒子３の中から電子部品の加工条件に応じた粒径の金属超微粒子３を選択し、その金属超微粒子３からなる、金属超微粒子層３ｂを半導体チップ１２の銅の金属端子２に配置する。その後、その金属超微粒子３の酸化皮膜を、その金属超微粒子３の粒径に応じて設定される３００℃以下の温度と時間以内で還元させることで、その金属端子２の表面に、その後に焼結する活性を残した金属超微粒子層３ｂを形成する。次に、その金属超微粒子層３ｂを、その下の半導体チップ１２の銅の配線パターン６の金属端子２の接合領域に押し当て加圧し、金属超微粒子３の粒径に応じて焼結を生じる３００℃以下の温度で前記金属超微粒子層３ｂを焼結させ、上方のチップ部品１２の銅の金属端子２とその下のチップ部品の銅の配線パターン６の所定領域の間に、両者を金属接合する厚さが直径の１０分の１以下の金属層、例えば、厚さが１μｍで直径が１０μｍの金属層を形成する。こうして、銅合金の金属超微粒子３によって形成した金属層で金属端子２が接合された半導体装置１３を製造することができる。なお、ここで、金属端子２あるいは配線パターン６としては、銅の表面にニッケルなどの中間層を介して表面に金めっきを形成したものを用い、その表面に銅合金の金属超微粒子３ｂ層を焼結させることで金属端子２と配線パターン６を金属接合させても良い。   In this example, metal ultrafine particles 3 of a copper alloy containing 50 atomic% or more of copper atoms are used, and a metal having a particle diameter corresponding to the processing conditions of the electronic component from among the ultrafine metal particles 3 having a particle diameter of 2 nm to 70 nm. The ultrafine particles 3 are selected, and the metal ultrafine particle layer 3 b made of the metal ultrafine particles 3 is disposed on the copper metal terminal 2 of the semiconductor chip 12. Thereafter, the oxide film of the metal ultrafine particles 3 is reduced within a time and at a temperature of 300 ° C. or less that is set according to the particle size of the metal ultrafine particles 3, and then on the surface of the metal terminal 2. The ultrafine metal particle layer 3b having the activity to be sintered is formed. Next, the ultrafine metal particle layer 3b is pressed against the bonding region of the metal terminal 2 of the copper wiring pattern 6 of the semiconductor chip 12 below, and sintering is generated according to the particle size of the ultrafine metal particle 3. The metal ultrafine particle layer 3b is sintered at a temperature of 300 ° C. or less, and the metal is interposed between a predetermined region of the copper metal terminal 2 of the upper chip component 12 and the copper wiring pattern 6 of the lower chip component 12. A metal layer having a thickness of 1/10 or less of the diameter, for example, a metal layer having a thickness of 1 μm and a diameter of 10 μm is formed. In this way, the semiconductor device 13 in which the metal terminal 2 is bonded with the metal layer formed by the ultrafine metal particles 3 of the copper alloy can be manufactured. Here, as the metal terminal 2 or the wiring pattern 6, a copper surface having a surface plated with gold through an intermediate layer such as nickel is used, and a copper alloy metal ultrafine particle 3 b layer is formed on the surface. The metal terminal 2 and the wiring pattern 6 may be metal-bonded by sintering.

［第３の実施例の効果］
第３の実施例では、銅の金属超微粒子３を用いて隣り合う半導体チップ１２の銅の金属端子２同士を金属接合するので、従来の半導体チップを重ね合わせて金属端子同士を接合するために金属端子上に形成していた金のバンプなどが不要になり、半導体装置１３の製造コストを低減できる効果がある。 [Effect of the third embodiment]
In the third embodiment, the copper metal terminals 2 of the adjacent semiconductor chips 12 are metal-bonded using the copper metal ultrafine particles 3, so that the conventional semiconductor chips are stacked and the metal terminals are bonded to each other. Gold bumps and the like that have been formed on the metal terminals become unnecessary, and the manufacturing cost of the semiconductor device 13 can be reduced.

以上、本発明についていくつかの実施例を説明したが、本発明は電子部品、その集合体のみならず、これらを搭載した電子機器にも適用され得ることは言うまでも無い。   As mentioned above, although several Example was described about this invention, it cannot be overemphasized that this invention is applicable not only to an electronic component and its aggregate | assembly but to the electronic device which mounts these.

図１は、本発明による製造方法の好ましい実施の形態を説明するための図である。FIG. 1 is a diagram for explaining a preferred embodiment of a production method according to the present invention. 図２は、図１に続く、本発明による製造方法の好ましい実施の形態を説明するための図である。FIG. 2 is a view for explaining a preferred embodiment of the manufacturing method according to the present invention, following FIG. 図３は、本発明者により、銅の金属超微粒子について焼結時間と焼結温度との関係を複数の粒径別に計算した結果を示す。FIG. 3 shows the result of the calculation of the relationship between the sintering time and the sintering temperature for a plurality of particle sizes by the present inventor for copper ultrafine particles. 図４は、本発明の第１の実施例として、多層の印刷配線板を製造する場合を説明するための図である。FIG. 4 is a diagram for explaining a case where a multilayer printed wiring board is manufactured as the first embodiment of the present invention. 図５は、本発明者により、チタンの金属超微粒子について焼結時間と焼結温度との関係を複数の粒径別に計算した結果を示す。FIG. 5 shows the result of calculation of the relationship between the sintering time and the sintering temperature for each of a plurality of particle sizes by the present inventor with respect to titanium ultrafine particles. 図６は、銅による第１の金属超微粒子と、これより小さな直径のチタンによる第２の金属超微粒子とを混合した場合の関係を示した図である。FIG. 6 is a view showing the relationship when the first metal ultrafine particles made of copper and the second metal ultrafine particles made of titanium having a smaller diameter are mixed. 図７は、本発明の第３の実施例として、マルチチップ型に構成した半導体装置の製造方法を説明するための図である。FIG. 7 is a diagram for explaining a method of manufacturing a semiconductor device configured as a multi-chip type as a third embodiment of the present invention.

符号の説明Explanation of symbols

１ 印刷配線板
２，２１ 金属端子
２ａ 第１の金属端子
２ｂ 第２の金属端子
３，３’ 金属超微粒子
３ａ 分散液
３ｂ 金属超微粒子層
４ 還元性ガス
５ 樹脂シート
５−１ 第１の絶縁基板
５−２ 第２の絶縁基板
６ 配線パターン
７ 金属柱
８ 吐出装置
９ プリプレグ
１２ 半導体チップ
１３ 半導体装置
１４ 半導体基板
１５ 機能素子
１６ 絶縁膜
１７ 開口
１８ ハードマスク
２０ インタポーザ
２１ はんだボール DESCRIPTION OF SYMBOLS 1 Printed wiring board 2,21 Metal terminal 2a 1st metal terminal 2b 2nd metal terminal 3,3 'Metal ultrafine particle 3a Dispersion liquid 3b Metal ultrafine particle layer 4 Reducing gas 5 Resin sheet 5-1 1st insulation Substrate 5-2 Second insulating substrate 6 Wiring pattern 7 Metal pillar 8 Discharge device 9 Prepreg 12 Semiconductor chip 13 Semiconductor device 14 Semiconductor substrate 15 Functional element 16 Insulating film 17 Opening 18 Hard mask 20 Interposer 21 Solder ball

Claims (9)

第１の電子部品の第１の金属端子の表面に、粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を分散した液体を吐出し、前記液体の媒体を蒸発させることで厚さ方向に直角な方向の直径が厚さの１０倍以上の金属超微粒子層を形成するとともに、前記金属超微粒子層における前記金属超微粒子の表面の酸化皮膜を、還元性ガスにより、前記金属超微粒子の粒径により定まる焼結時間よりも短い時間で還元する第１の工程と、
次に、前記金属超微粒子層を形成した前記第１の金属端子に対向させて第２の電子部品の第２の金属端子を接触させ加熱し加圧することで、前記第１の金属端子及び第２の金属端子同士を、その間の前記金属超微粒子を焼結させることで金属接合させる第２の工程と、
を有することを特徴とする電子部品の集合体の製造方法。 A liquid in which metal ultrafine particles having a particle diameter of 0.5 nm to 70 nm are dispersed is ejected onto the surface of the first metal terminal of the first electronic component, and the medium of the liquid is evaporated to make a right angle in the thickness direction. Forming a metal ultrafine particle layer having a diameter of 10 times or more as large as the thickness of the metal ultrafine particle and reducing the oxide film on the surface of the metal ultrafine particle in the metal ultrafine particle layer with a reducing gas. A first step of reducing in a time shorter than the sintering time determined by:
Next, the second metal terminal of the second electronic component is brought into contact with the first metal terminal on which the metal ultrafine particle layer is formed, and is heated and pressurized to thereby form the first metal terminal and the first metal terminal. A second step in which two metal terminals are metal-bonded by sintering the metal ultrafine particles therebetween;
A method for producing an assembly of electronic components, comprising: 前記金属超微粒子が、銅あるいは銅の合金から成り、粒子の直径が２ｎｍから７０ｎｍであり、
前記第１、第２の電子部品がそれぞれ、表面に前記第１、第２の金属端子が形成された樹脂シートを有し、
前記第２の工程が、前記第１の金属端子に前記金属超微粒子層を形成した前記樹脂シートとプリプレグを交互に重ね、積層し加熱加圧してプリプレグを硬化させることにより前記樹脂シート同士を接着すると同時に、対向する前記樹脂シートの前記第１、第２の金属端子同士を、その間の前記金属超微粒子を焼結させることで金属接合させる工程であり、
前記電子部品の集合体が印刷配線板である、
ことを特徴とする請求項１記載の電子部品の集合体の製造方法。 The metal ultrafine particles are made of copper or a copper alloy, and the diameter of the particles is 2 nm to 70 nm.
Each of the first and second electronic components has a resin sheet on the surface of which the first and second metal terminals are formed,
In the second step, the resin sheets and the prepreg in which the ultrafine metal particle layer is formed on the first metal terminal are alternately stacked, laminated, and heated and pressed to cure the prepreg, thereby bonding the resin sheets together. At the same time, the first and second metal terminals of the resin sheet facing each other is a step of metal joining by sintering the metal ultrafine particles therebetween,
The assembly of electronic components is a printed wiring board,
The method of manufacturing an assembly of electronic components according to claim 1. 前記金属超微粒子層が、前記金属超微粒子と、該金属超微粒子と大きさが４倍以上異なる金属微粒子とを混合して形成される、
ことを特徴とする請求項１記載の電子部品の集合体の製造方法。 The metal ultrafine particle layer is formed by mixing the metal ultrafine particles and metal fine particles different in size by 4 times or more from the metal ultrafine particles.
The method of manufacturing an assembly of electronic components according to claim 1. 第１の電子部品の第１の金属端子と第２の電子部品の第２の金属端子を接合させた接合部分を有する電子部品の集合体であって、該接合部分が、対向する前記第１、第２の金属端子の間に粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を焼結させて成る、厚さ方向に直角な方向の直径が厚さの１０倍以上の金属層を有することを特徴とする電子部品の集合体。   An assembly of electronic components having a joint portion obtained by joining a first metal terminal of a first electronic component and a second metal terminal of a second electronic component, wherein the joint portions are opposed to each other. And a metal layer having a diameter in the direction perpendicular to the thickness direction of 10 times or more of the thickness formed by sintering metal ultrafine particles having a particle diameter of 0.5 nm to 70 nm between the second metal terminals. An assembly of electronic components characterized by that. 前記金属超微粒子が、粒子の直径が２ｎｍから７０ｎｍの銅あるいは銅の合金であり、
前記第１の電子部品と第２の電子部品がそれぞれ、表面に前記第１、第２の金属端子が形成された樹脂シートを有し、
前記第１の電子部品と第２の電子部品の接合部分が、前記樹脂シートがプリプレグにより接着されるとともに、対向する前記樹脂シートの前記第１、第２の金属端子同士が、その間の前記金属超微粒子を焼結させることで金属接合され、
前記電子部品の集合体が印刷配線板である、
ことを特徴とする請求項４記載の電子部品の集合体。 The metal ultrafine particles are copper or a copper alloy having a particle diameter of 2 nm to 70 nm,
Each of the first electronic component and the second electronic component has a resin sheet on the surface of which the first and second metal terminals are formed,
The joint portion between the first electronic component and the second electronic component is bonded to the resin sheet by a prepreg, and the first and second metal terminals of the resin sheet facing each other are the metal between them. Metal bonding is achieved by sintering ultrafine particles,
The assembly of electronic components is a printed wiring board,
The assembly of electronic parts as claimed in claim 4. 前記金属層が、大きさが４倍以上異なる２種類の金属微粒子から形成された、
ことを特徴とする請求項４記載の電子部品の集合体。 The metal layer was formed from two kinds of metal fine particles having a size different by 4 times or more,
The assembly of electronic parts as claimed in claim 4. 請求項４〜６のいずれかに記載の電子部品の集合体を搭載した電子機器。   The electronic device carrying the aggregate | assembly of the electronic component in any one of Claims 4-6. 粒子の直径が２ｎｍから７０ｎｍの銅あるいは銅成分が５０原子％以上の銅合金による金属超微粒子の中から電子部品の加工条件に応じた粒径の金属超微粒子を選択する工程と、
次に、選択した粒径の金属超微粒子からなる、厚さ方向に直角な方向の直径が厚さの１０倍以上の金属超微粒子層を第１の電子部品の第１の金属端子に配置した後、当該金属超微粒子の酸化皮膜を、前記選択した粒径に応じて設定される温度と時間以内で還元させることで、前記第１の金属端子の表面に、その後に焼結する活性を残した金属超微粒子層を形成する工程と、
次に、前記金属超微粒子層の表面に第２の電子部品の第２の金属端子を重ね合わせ、前記選択した粒径に応じて設定され焼結を生じる温度で前記金属超微粒子を焼結させることで、前記第１、第２の金属端子を前記金属超微粒子によって金属接合させる工程と、
を有することを特徴とする電子部品の集合体の製造方法。 Selecting ultrafine metal particles having a particle size according to the processing conditions of the electronic component from ultrafine metal particles having a diameter of 2 nm to 70 nm of copper or a copper alloy having a copper component of 50 atomic% or more;
Next, a metal ultrafine particle layer made of metal ultrafine particles having a selected particle diameter and having a diameter in a direction perpendicular to the thickness direction of 10 times or more of the thickness is disposed on the first metal terminal of the first electronic component. Thereafter, the oxide film of the ultrafine metal particles is reduced within a temperature and time set in accordance with the selected particle size, thereby leaving an activity for subsequent sintering on the surface of the first metal terminal. Forming a metal ultrafine particle layer,
Next, the second metal terminal of the second electronic component is superimposed on the surface of the ultrafine metal particle layer, and the ultrafine metal particles are sintered at a temperature that is set according to the selected particle size and causes sintering. Then, the step of metal joining the first and second metal terminals by the metal ultrafine particles,
A method for producing an assembly of electronic components, comprising: 第１の電子部品の第１の金属端子と第２の電子部品の第２の金属端子を接合させた接合部分を有する電子部品の集合体であって、該接合部分が、対向する前記第１、第２の金属端子の間に、銅あるいは銅成分が５０原子％以上の銅合金からなる、粒子の直径が０．５ｎｍから７０ｎｍの金属超微粒子を焼結させて成る、厚さ方向に直角な方向の直径が厚さの１０倍以上の金属層を有することを特徴とする電子部品の集合体。
An assembly of electronic components having a joint portion obtained by joining a first metal terminal of a first electronic component and a second metal terminal of a second electronic component, wherein the joint portions are opposed to each other. , Between the second metal terminals, made of copper or a copper alloy having a copper component of 50 atomic% or more, sintered with ultrafine metal particles having a particle diameter of 0.5 nm to 70 nm, and perpendicular to the thickness direction. An assembly of electronic components, comprising a metal layer having a diameter in a specific direction that is 10 times or more the thickness.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007242900A (en) * 2006-03-09 2007-09-20 Fujitsu Ltd Electron device, and its manufacturing method
JP2008244242A (en) * 2007-03-28 2008-10-09 Hitachi Ltd Semiconductor device and its manufacturing method, and composite metallic body and its manufacturing method
JP2008258611A (en) * 2007-03-30 2008-10-23 Xerox Corp Forming method of wire layer, sealing layer and shielding layer by ink-jet printing
JP2012054358A (en) * 2010-08-31 2012-03-15 Fujitsu Ltd Method of manufacturing electronic device
JP2012216612A (en) * 2011-03-31 2012-11-08 Toyota Industries Corp Electronic component module and manufacturing method therefor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001217548A (en) * 2000-02-03 2001-08-10 Hitachi Cable Ltd Method of manufacturing wiring board
JP2001225180A (en) * 2000-02-18 2001-08-21 Ebara Corp Method of joining metal
JP2003008209A (en) * 2001-06-19 2003-01-10 Sony Corp Conductive bonding material, multilayer printed wiring board, and manufacturing method thereof
JP2004119686A (en) * 2002-09-26 2004-04-15 Harima Chem Inc Method of forming fine wiring pattern
JP2005116612A (en) * 2003-10-03 2005-04-28 Murata Mfg Co Ltd Flip chip packaging method and electronic circuit device using the same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001217548A (en) * 2000-02-03 2001-08-10 Hitachi Cable Ltd Method of manufacturing wiring board
JP2001225180A (en) * 2000-02-18 2001-08-21 Ebara Corp Method of joining metal
JP2003008209A (en) * 2001-06-19 2003-01-10 Sony Corp Conductive bonding material, multilayer printed wiring board, and manufacturing method thereof
JP2004119686A (en) * 2002-09-26 2004-04-15 Harima Chem Inc Method of forming fine wiring pattern
JP2005116612A (en) * 2003-10-03 2005-04-28 Murata Mfg Co Ltd Flip chip packaging method and electronic circuit device using the same

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007242900A (en) * 2006-03-09 2007-09-20 Fujitsu Ltd Electron device, and its manufacturing method
JP4672576B2 (en) * 2006-03-09 2011-04-20 富士通株式会社 Electronic device and manufacturing method thereof
JP2008244242A (en) * 2007-03-28 2008-10-09 Hitachi Ltd Semiconductor device and its manufacturing method, and composite metallic body and its manufacturing method
JP2008258611A (en) * 2007-03-30 2008-10-23 Xerox Corp Forming method of wire layer, sealing layer and shielding layer by ink-jet printing
JP2012054358A (en) * 2010-08-31 2012-03-15 Fujitsu Ltd Method of manufacturing electronic device
JP2012216612A (en) * 2011-03-31 2012-11-08 Toyota Industries Corp Electronic component module and manufacturing method therefor

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