JP4101241B2 - Capacitor including end face electrode layer formed by sputtering and method for manufacturing the same - Google Patents

Description

  The present invention is a capacitor, in particular, a PML (polymer multilayer) capacitor, that is, a dielectric layer composed of a thin film polymer layer and internal electrode layers laminated on both sides thereof as a basic element unit of the capacitor and connected to each internal electrode. The present invention relates to a capacitor having an end face electrode (external electrode), in which a metal-containing portion of the end face electrode is formed by sputtering, and a method for manufacturing the same.

  The end face electrodes of conventional film capacitors (capacitors obtained by winding or laminating a metal film on which an internal electrode is deposited on a polymer film with a thickness of 1 μm or more) are generally formed by metallicon (metal spraying). It was the target. Metallicons are inexpensive and have the advantage of high film formation speed. Since the inner electrode lead-out end face of such a capacitor is just a film stack, there is an interlayer that is relatively larger than the thickness of the film per layer, and the sprayed metal has a certain depth to the inside of the interlayer. By connecting, it physically connects to the internal electrode. In addition, since ordinary films are laminated slightly shifted every other layer, a gap (unevenness) is formed on the end face, thereby strengthening the physical bond between the internal electrode and the metallized (metal sprayed) metal. Therefore, there is no particular problem in terms of electrical characteristics and adhesive strength.

  However, the step of vapor-depositing an internal electrode on a dielectric (polymer thin film) formed by vapor deposition and radiation curing in vacuum, and then forming the next dielectric layer on the internal electrode layer by means equivalent to the above means If the metallicon method is used for a capacitor element such as PML, which is characterized by continuously forming the capacitor base element by repeating the process as many times as necessary, the thermal spraying is caused by the following causes: Therefore, it is difficult to obtain a durable capacitor element having characteristics that are excellent in terms of electrical characteristics and adhesive strength.

(1) The thickness of the PML capacitor element per dielectric layer is very thin. In general, the film for a capacitor is about 1.0 μm at the thinnest, considering the film manufacturing technology and the processing technology for the capacitor. The vapor deposition type dielectric layer (polymer layer) can be easily formed to 1.0 μm or less.

(2) The PML capacitor element has no gap between the end faces. The PML capacitor element manufactured by laminating while continuously forming the dielectric layer and the internal electrode layer in a vacuum, When a large gap between layers as seen in a multilayer capacitor using the deposited film is formed, delamination may occur, resulting in a fatal defect as a capacitor.

(3) The end face of the PML capacitor element must be very smooth. The PML capacitor that manufactures the multilayer capacitor mother element by continuously repeating the formation of the dielectric layer and internal electrode layer in advance in a vacuum Because cutting is performed by a technique such as dicing, the end face is very different compared to the case where a vapor deposition film is laminated while slightly shifting each layer so that a gap (unevenness) is formed on the end face as seen in conventional film capacitor elements. It is smooth. However, there is also a technology that makes it possible to apply the metallicon method on the end face of the PML capacitor element considerably with plasma, but in order to obtain sufficient adhesion strength, the processing conditions must be performed properly. Therefore, sufficient characteristics as a capacitor cannot be extracted.

As described above, a PML type multilayer film capacitor in which a multilayer body is formed by vapor deposition in a vacuum can make the dielectric layer as thin as 1.0 μm or less, and the end face shape is the conventional one. Since it is relatively smoother than a film capacitor and has no gaps, it is difficult to obtain an anchor effect when forming an end face electrode by the conventional metallicon (metal spraying) method. Therefore, the adhesion strength between the end face electrode and the element is weakened.
Furthermore, even when the contact area with the internal electrode is increased, a very thin internal electrode layer is exposed alone on the end face of the capacitor element forming the end face electrode, the metal particles are large, and the spraying pressure is relatively high. In the metallicon (metal spraying) method, the internal electrode is bent or scattered, so that sufficient joining is not performed between the end face electrode and the internal electrode metal-containing layer.
As a result, in the PML capacitor, the end surface electrode forming method by the conventional metallicon (metal spraying) method cannot provide good electrical characteristics, and a capacitor with poor adhesion strength between the element and the end surface electrode can be manufactured. Increases sex.
In order to manufacture a PML capacitor using a conventional film capacitor manufacturing method (metallicon), there are problems to be improved as described above.

  Conventionally, as a method for manufacturing a PML capacitor, a reactive acrylate monomer is deposited on a rotating drum via a heating evaporator to form a thin monomer layer, and the thin monomer layer is crosslinked by electron beam irradiation to form a dielectric. A film layer is formed, and a step of forming a metal-containing layer constituting the internal electrode thereon by vapor deposition is performed a plurality of times, and sandwiched between the metal layer to be a pair of internal electrodes and the internal electrode metal-containing layer. It is known that the polymer dielectric layers are sequentially laminated, and external electrodes connected to the respective internal electrodes are provided by soldering on both side surfaces of the capacitor laminate unit (see Patent Document 1). In this case, as the metal material, there is an explanation that any metal that can be conventionally used can be used, but specifically, aluminum is described. Here, Patent Document 1 describes the term “a multiplayer sputtered, solder-coated termination strip”, but its specific configuration is described. Furthermore, nothing is described about the formation method of the multilayer structure and the material for forming the layer.

  As for the method of forming the external electrode, an organic polymer substrate, a pair of external electrodes provided in the form of an organic polymer substrate, an internal electrode connected to one of the external electrodes, and another electrode of the external electrode In the production of a capacitor in which an internal electrode connected to a capacitor is provided via a dielectric, the internal electrode is formed by vapor deposition or sputtering, and the monomer is polymerized on the internal electrode by vaporizing and vapor-depositing the monomer. It is known to form by this, and to form the external electrode by vapor deposition or sputtering (see Patent Document 2). In this method, the external electrode is formed by etching a copper foil on an organic polymer substrate and performing electroless nickel plating or gold plating thereon.

  However, this method does not disclose a PML type capacitor in which a resin thin film and a metal thin film are sequentially laminated on a drum in a vacuum space, and suggests a method for manufacturing an end face electrode of the PML type capacitor. Not a thing.

  Furthermore, as a method for forming an end face electrode of an electronic component, a metallized coating is applied by a low-temperature sputtering apparatus having a magnetron-type electrode structure on the end face of the electronic component under vacuum instead of the conventional electrode formation method by the metallicon method. It is known to form end face electrodes (see Patent Document 3). And it is disclosed also about the metallized film capacitor as an example of the electronic component, and further, the end face electrode is formed by forming Al by low temperature sputtering and further depositing Cu by low temperature sputtering to form a conductive layer, It is also disclosed that the end face is reverse-sputtered and etched before sputtering, and a conductive paint is applied to the outside of the sputtered metal layer (see Patent Document 3).

  However, this method does not disclose a PML type capacitor in which a resin thin film and a metal thin film are sequentially laminated several times in a vacuum space, nor does it suggest a method for manufacturing an end face electrode of the PML type capacitor. . Furthermore, there is no description or suggestion regarding a specific combination of metals constituting the metal-containing layer of the end face electrode, or a specific combination related to the combination of the metal and the conductive resin layer.

  As described above, the prior art document discloses that sputtering is used to form an end face electrode of a PML type capacitor formed by sequentially laminating a resin thin film and a metal thin film a plurality of times in a vacuum space. It has not been suggested or suggested. In addition, the metal, alloy, metal oxide, alloy oxide, other metal compound other than the oxide or a specific combination of alloy compounds constituting the metal-containing layer of the end face electrode, or a specific combination of these and the conductor resin layer There is no description or suggestion regarding the combination.

US Pat. No. 6,092,269 (column 3, line 45 to column 5, line 13, column 9, line 48 to line 57 and column 10, line 66, and FIGS. 1, 2 and 6a). (Fig. And Fig. 6b) JP-A-9-283370 (Claim 8, paragraphs 0009, 0011, 0013, 0016 and 0017 and FIGS. 1, 2, 4 and 5 to 7) JP-A-52-151854 (page 3, upper left column, lines 5 to 12, upper right column, lines 4 to 14, lower left column, last line to lower right column, line 5 and Example 2 and Example) 4)

  The present invention solves the above-mentioned various problems in the formation of the end face electrode of the conventional capacitor element, and in the compact PML type capacitor element, the end face electrode having high mechanical strength and excellent electrical characteristics is ensured. An object of the present invention is to provide a capacitor manufacturing method and a capacitor obtained thereby, which are easily formed.

The present invention provides a capacitor element manufactured by alternately laminating a resin thin film layer and an internal electrode metal-containing layer serving as a dielectric layer by vacuum deposition in vacuum in the first aspect, and an end face thereof. In the capacitor provided with the electrode provided in, the resin thin film layer is formed of an acrylic resin,
The electrode provided on the end face includes a metal-containing portion formed by sputtering , and the metal-containing portion formed by sputtering includes Al, Ti, V, Cr, Ni, Cu, Zn, Zr, and Nb. , Mo, Hf, Ta and W selected from the group consisting of a simple substance, an oxide of the metal, or a compound other than the oxide of the metal, or Al, Ti, V, Cr, Ni , Cu, Zn, Zr, Nb, Mo, Hf, an alloy containing at least one selected from the group consisting of Ta, and W, an oxide of the alloy, or a compound other than the oxide of the alloy And at least a part of the metal-containing portion formed by sputtering is directly bonded to the internal electrode metal of the capacitor element, and is directly connected to the internal electrode. Metal or alloy of the metal-containing portion formed by sputtering, to Ti, Cr, Mo, Ta, characterized in that from the group consisting of W and Ni-Cr is any one metal or alloy selected Concerning capacitors.

In the second aspect, the present invention relates to the first aspect, wherein the metal-containing portion formed by sputtering is formed as a single layer , or as a plurality of layers of the same component metal or different component metals. It is related with the capacitor | condenser characterized by being made .

In the third aspect, the present invention relates to the first or second aspect, wherein the metal-containing part is at least a part of the metal-containing part formed by sputtering and directly joined to the internal electrode metal of the capacitor element. An outer metal-containing layer made of any one of a metal or an alloy selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni-V, and Ti-W is provided outside the portion. It relates to a capacitor.

Moreover, in the fourth aspect, the present invention relates to the third aspect, wherein at least part of the metal-containing portion formed by the sputtering and further outside the outer metal-containing layer, Ni, Cu, The present invention relates to a capacitor having an outer coating metal-containing layer made of any one of a metal or an alloy selected from the group consisting of Mo and Ni-Cu.

According to a fifth aspect, the present invention relates to the first to fourth aspects, wherein the capacitor has a conductive resin layer on an end face electrode in addition to the metal-containing portion formed by the sputtering. About.

In the sixth aspect, the present invention relates to the first to fifth aspects, in addition to the metal-containing portion formed by the sputtering, the end face electrode is at least one of electrolytic plating, electroless plating, and hot dipping. The present invention relates to a capacitor having a metal-containing layer formed by two methods.

According to a seventh aspect, the present invention relates to the capacitor according to the sixth aspect, further comprising a metal-containing layer formed by Ni plating outside the metal-containing portion formed by the sputtering. .

Further, in an eighth aspect, the present invention relates to the fifth aspect, wherein the electrodes provided on the end surface are configured in the order of a metal-containing portion formed by sputtering and an outer conductive resin layer. It is related with the capacitor characterized by having.

In the ninth aspect, the present invention relates to the sixth aspect, wherein the electrode provided on the end face is formed by a metal-containing portion formed by sputtering in order from the inside, a conductive resin layer, and plating. It is related with the capacitor | condenser comprised by the metal containing layer.

In the tenth aspect, the present invention relates to the first to ninth aspects, wherein the sputtering is performed by a magnetron sputtering system, a bipolar sputtering system, an ion beam sputtering system, a tripolar sputtering system, and a quadrupole sputtering system. It is related with the capacitor | condenser implemented by at least 1 type selected from a group.

Moreover, in the eleventh aspect, the present invention relates to the first to tenth aspects, wherein the metal-containing portion of the electrode formed by sputtering performs sputtering continuously in vacuum a plurality of times. The present invention relates to a capacitor comprising a plurality of formed metal-containing layers.

According to a twelfth aspect, the present invention relates to the first to eleventh aspects, wherein the end surface is surface-treated with plasma before the electrode is formed on the capacitor end surface. Concerning capacitors.

According to a thirteenth aspect, the present invention relates to the capacitor according to the twelfth aspect, wherein the plasma is generated from a gas containing at least oxygen.

Further, in the fourteenth aspect, the present invention relates to the first to thirteenth aspect, wherein the capacitor element comprises a dielectric composed of a resin thin film layer and a group consisting of Al, Zn, Cu, Ag and Ni. Metals selected, metal oxides other than these, metal compounds other than these metal oxides, alloys containing at least one of those metals, oxides of the alloys, or oxides of the alloys The present invention relates to a capacitor formed by alternately laminating a plurality of internal electrode metal-containing layers made of a compound.

In the fifteenth aspect, the present invention relates to the first to fourteenth aspects, wherein the resin thin film layer is made of any of a radiation curable resin, an ultraviolet curable resin, and a thermosetting resin. It is related with the capacitor characterized by this.

Further, in a sixteenth aspect, the present invention is a method of manufacturing a capacitor according to the first aspect, comprising: a resin thin film layer that becomes a dielectric layer and an internal electrode metal-containing layer by continuous vapor deposition in vacuum A capacitor element is formed by alternately laminating layers, and an end face electrode including a metal-containing portion formed by sputtering is formed on the end face of the capacitor element.

Furthermore, in the seventeenth aspect, the present invention relates to the sixteenth aspect, wherein the metal-containing portion formed by sputtering is formed in a plurality of layers with the same component metal , or with different metal components. The present invention relates to a method for manufacturing a capacitor, which is constituted by forming a plurality of layers .

Furthermore, in an eighteenth aspect, the present invention relates to the sixteenth or seventeenth aspect, wherein the electrode provided on the end face is sequentially formed from the inside by a metal-containing portion, a conductive resin layer, Further, the present invention relates to a method for manufacturing a capacitor, wherein the capacitor is formed by laminating metal-containing layers formed by plating.

  In the present specification, the “metal-containing portion” means a portion containing a metal simple substance, a metal oxide, or a metal-containing compound other than a metal oxide, or a portion containing an alloy simple substance, an alloy oxide or an alloy compound other than an alloy oxide. Is used as a term meaning each of them, or as a term generically referring to them.

  In the specification of the present application, the “outer metal-containing layer” is a layer formed outside the “metal-containing portion”, and includes a metal simple substance, a metal oxide, or a metal-containing compound other than the metal oxide, Alternatively, it is used as a term meaning an individual alloy, a layer containing an alloy oxide or an alloy compound other than an alloy oxide, and a term generically referring to them.

  In the specification of the present application, the “outer coating metal-containing layer” is a layer formed on the outer side of the “outer metal-containing layer”, and includes a metal simple substance, a metal oxide, or a metal-containing compound other than a metal oxide. It is used as a term meaning a single layer, a single alloy, an individual layer of an alloy oxide or a layer containing an alloy compound other than an alloy oxide, and a term generically referring to them.

  In the present specification, the “metal-containing layer” is a layer containing a metal simple substance, a metal oxide, or a metal-containing compound other than a metal oxide, or a layer containing an alloy simple substance, an alloy oxide or an alloy compound other than an alloy oxide. Are used as a term for the individual layers, and as a term generically referring to them.

  By having the structural features as described above, the present invention solves the above-mentioned various problems in the formation of the end face electrodes of the conventional capacitor element. In a compact PML type capacitor element, the mechanical strength is large, It is possible to provide a method for reliably and simply manufacturing an end face electrode having excellent mechanical characteristics, and a capacitor obtained by the method.

  According to the present invention, by adopting a sputtering means having a small metal particle size as a means for forming the end face electrode, the particles having a small particle size can easily enter the internal electrode layer to make the electrical contact extremely good. At the same time, since the particles adhere to the dielectric layer, the adhesion strength between the end face electrode and the device is stronger than that of metal spraying, so that the electrical characteristics are also improved and a capacitor with good characteristics with low loss resistance is provided. The effect which can be obtained is obtained. As the thickness of one dielectric layer is reduced, the formation of the end face electrode using the sputtering means is superior to the metallicon means as the method for forming the electrode formed on the end face of the PML capacitor element. It will increase the nature.

  In the present invention, since the sputtering method is a vacuum process, a dense metal film with few impurities can be formed. This also makes it possible to provide a capacitor with low loss resistance and good electrical characteristics.

  In the following, preferred embodiments for carrying out the invention of the present application will be described with respect to preferred specific embodiments of the components of the invention of the present application, and the effects obtained therewith will be described as necessary.

  The simple metal constituting the “metal-containing portion” in the present specification is a metal selected from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta, and W. is there.

The metal oxide constituting the “metal-containing portion” in the present specification is a metal selected from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta, and W. It is a metal oxide containing.
Specifically, Al ₂ O ₃ , TiO ₃ , Ti ₂ O ₃ , V ₂ O ₅ , V ₂ O ₃ , Cr ₂ O ₃ , NiO, CuO, ZnO, ZrO ₂ , Nb ₂ O ₅ , MoO ₃ , such as _{MoO 2, HfO 2, Ta 2} O 5, WO 3 can be exemplified.

The metal compound other than the metal oxide constituting the “metal-containing portion” in the present specification is from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta and W. A metal compound containing a selected metal.
Specifically, TiN, WN, TaN, etc. can be illustrated.

The alloy constituting the “metal-containing portion” in the present specification includes a metal selected from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta, and W. It is an alloy.
Specific examples include Ni—Cr, Ni—V, Ni—Cu, Al—Cu, Ti—W, Ta—Al, Cu—Zr, Cu—Zn, and Mo—W.

The alloy oxide constituting the “metal-containing portion” in the present specification is a metal selected from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta, and W. It is an alloy oxide containing.
The oxide of the alloy illustrated by the preceding clause can be illustrated.

The alloy compound other than the alloy oxide constituting the “metal-containing portion” in the present specification is from the group consisting of Al, Ti, V, Cr, Ni, Cu, Zn, Zr, Nb, Mo, Hf, Ta and W. An alloy compound containing a selected metal.
Specifically, WSiN, TaSiN, etc. can be illustrated.

  The single metal or alloy constituting the “outer metal-containing layer” in the present specification is a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W.

The metal oxide constituting the “outer metal-containing layer” in the present specification is a metal oxide containing a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W. It is.
_{Specifically, TiO 2, Ti 2 O 3} , NiO, etc. _{ZrO 2, Nb 2 O 5,} HfO 2, Ta 2 O 5, WO 3 can be exemplified.

The metal compound other than the metal oxide constituting the “outer metal-containing layer” in the present specification is a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W. It is a metal compound containing.
Specifically, TiN, TaN, etc. can be illustrated.

The alloy constituting the “outer metal-containing layer” in the present specification is an alloy containing a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W.
Specifically, Ni-Cr, Ta-Al, Ni-V, Ti-W, etc. can be illustrated.

The alloy oxide constituting the “outer metal-containing layer” in the present specification is an alloy oxide containing a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W. It is.
Specifically, the oxides of the alloys exemplified in the previous section can be exemplified.

The alloy compound other than the alloy oxide constituting the “outer metal-containing layer” in the present specification is a metal selected from the group consisting of Ti, Ni, Zr, Nb, Hf, Ta, Ni—V, and Ti—W. It is an alloy compound containing.
Specifically, TaSiN etc. can be illustrated.

  The simple metal or the alloy constituting the “outer coating metal-containing layer” in the present specification is a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.

The metal oxide constituting the “outer coating metal-containing layer” in the present specification is a metal oxide containing a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.
Specifically, NiO, CuO, MoO ₃ , MoO _{2 and the} like can be exemplified.

  The metal compound other than the metal oxide constituting the “outer coating metal-containing layer” in the present specification is a metal compound containing a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.

The alloy constituting the “outer coating metal-containing layer” in the present specification is an alloy containing a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.
Specifically, Ni—Cr, Ni—V, Ni—Cu, Al—Cu, Cu—Zr, Cu—Zn, Mo—W, and the like can be exemplified.

The alloy oxide constituting the “outer coating metal-containing layer” in the present specification is an alloy oxide containing a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.
Specifically, the oxides of the alloys exemplified in the previous section can be exemplified.

  The alloy compound other than the alloy oxide constituting the “outer coating metal-containing layer” in the present specification is an alloy compound containing a metal selected from the group consisting of Ni, Cu, Mo, and Ni—Cu.

  In the present invention, the thickness of the “metal-containing portion” formed by sputtering in which at least a part is directly bonded to the internal electrode metal of the capacitor element is 0.001 μm to 0.3 μm, and the “outer metal-containing layer” The thickness is 0.001 μm to 1.0 μm, and the thickness of the “outer coating metal-containing layer” is 0.1 μm to 5.0 μm.

  The sputtering method used in the present invention is at least one selected from the group of magnetron sputtering, dipole sputtering, ion beam sputtering, tripolar sputtering, and quadrupole sputtering. These methods are known as general sputtering methods.

  Further, the plating method used for the end face electrode in the present invention is based on at least one method of electrolytic plating, electroless plating, and hot dipping. These plating methods are known as general plating methods.

In the manufacturing process of the PML capacitor of the present invention, the vacuum environment varies depending on the process. Specifically, when manufacturing the PML capacitor element, about 10 ⁻⁴ Pa to 10 ² Pa, more preferably 10 ⁻³ Pa to 1.0 Pa. In the plasma processing step of the end face, it is about 10 to 100 Pa, more preferably about 20 Pa to 50 Pa, and when forming an electrode by sputtering, the degree of vacuum is about 10 ⁻² Pa to 10 Pa.

  As the resin constituting the thin film resin layer in the present invention, either a radiation curable resin, an ultraviolet curable resin, or a thermosetting resin is used.

Among them, A acrylic resin, especially the ease of manufacture, preferred from the side of the resulting capacitor characteristics.

  Examples of the resin curable with radiation, ultraviolet rays, or heat used in the present invention include, for example, a simple substance or a mixture of compounds having at least one ethylenically unsaturated double bond in the molecule, and 1 cationic polymerizable group in the molecule. Examples thereof include a single compound or a mixture of compounds having at least one compound. Specifically, unsaturated polyester resin, polyester polyacrylate resin, polyester polymethacrylate resin, epoxy polyacrylate resin, epoxy polymethacrylate resin, urethane polyacrylate resin, urethane polymethacrylate resin, acrylic polyacrylate resin, acrylic polymethacrylate resin, Examples are vinyl resins. Specific examples include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, tricyclodecane dimethanol diacrylate, trimethylolpropane triacrylate, and the like. A curing accelerator or the like can be used in combination as necessary.

  In forming these resin thin layers by vapor deposition, the raw materials are supplied in the form of monomers or oligomers, deposited on a rotating drum, and irradiated with radiation such as electron beams or ultraviolet rays, or It is cured by heating. Alternatively, these means may be combined and cured.

If necessary, an additive may be added to the monomer or oligomer of the resin. Examples of such additives include a photopolymerization initiator (at the time of curing with ultraviolet rays), a thermal polymerization initiator (at the time of thermal curing), an antioxidant, and an adhesion improver. Specific examples are shown below.
* Photopolymerization initiator ○ Acetophenone series:
1-hydroxycyclohexyl-phenyl ketone 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one
・ 2,4-Diethylthioxanthone ○ Others include “benzoin ether” and “benzophenone”.
* Thermal polymerization initiator ○ Peroxide, benzoyl peroxide, t-butyl hydroperoxide ○ Azo compound, azobisisobutyronitrile * Antioxidant, Ethylenebis (oxyethylene) bis [3- (5-tert-butyl -4-hydroxy-m-tolyl) propionate]
・ Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate * Adhesion improver ○ Silane coupling agent ・ Vinyltrimethoxysilane ・ Methyltrimethoxysilane

  Examples of the resin component constituting the conductive resin layer in the end face electrode of the present invention include thermosetting resins such as acrylic, epoxy, phenol, urethane, silicon, and polyimide.

  Moreover, as an additive which mixes with the resin component which comprises the electroconductive resin layer in the end surface electrode of this invention and provides electroconductivity, metal powders, such as silver, copper, nickel, gold | metal | money, the metal of those metal alloys Examples include powder and carbon powder.

  Various additives can be added to the resin component forming the various layers as necessary.

  In particular, in the specific form of the present invention, when Cr is used as the metal in the lowermost layer (first layer) of the end face electrode, that is, the metal-containing portion formed by sputtering directly bonded to the internal electrode, the element and the end face electrode The effect of increasing the adhesion strength is obtained. This is presumably because Cr has better adhesion to the resin that is the dielectric of the device than other metals, and when Al is used as the internal electrode, it also has good adhesion to Al.

  In the present invention, in particular, in the present invention, when a polymer containing oxygen, particularly an acrylic resin, is used as a polymer layer, Cr is easily bonded to an oxygen atom, and therefore a polymer having a functional group or the like that can be bonded with O- on the surface. Particularly good adhesion, that is, the acrylic resin, which is the dielectric of PML type capacitors, is thought to have O-bonds on the surface. It is considered that the adhesion strength can be improved by forming.

  Further, Cr has good adhesion to the oxide, which is considered to form diffusion bonding on both the metal and the oxide because Cr is easily oxidized and diffused to some extent. Furthermore, Al is a metal whose surface is easily oxidized and has good adhesion with Cr for the reasons described above.

  Here, in addition to the above reasons, when considering the adhesion between Cr and Al, since Cr is a hard metal, in sputtering where the energy of the particles is relatively large, Cr particles are a relatively soft metal such as Al or It is considered that the polymer is difficult to penetrate and, therefore, the adhesion with Al or polymer is superior to other metals.

  Specifically, the Cr layer is preferably about 0.001 μm to 0.3 μm, more preferably about 0.002 μm to 0.1 μm, and particularly preferably about 0.005 μm to 0.05 μm.

  In addition to Cr, the same effect can be obtained by using, as the first layer, a metal selected from the group consisting of Ti, Mo, Ta, W, and Ni—Cr.

  Further, in the embodiment of the present invention, at least a part of the metal-containing part formed by sputtering and outside the metal-containing part directly joined to the internal electrode metal of the capacitor element, Ti, Ni, Zr, Nb , Hf, Ta, Ni-V, and Ti-W, the outer metal-containing layer (second layer) containing any one metal selected from the group consisting of these metals, When Ni or Ni-V is used for the second layer, this outer metal-containing layer (second layer) functions as a barrier layer that prevents diffusion between the metal-containing layers. For example, when Cu is used for the third layer, It is possible to prevent the diffusion of Al of the internal electrode, the first layer of metal, and Cu.

  Furthermore, the Ni oxide film can only be made thin on the surface, and since the oxide film is very stable, it prevents the oxidation from proceeding to the inside, and the stable oxide film also has a barrier property against moisture. Therefore, the characteristics of the end face electrode can be maintained.

  However, since Ni is a metal having a relatively high resistivity and poor conductivity like Cr, the layer thickness must be reduced in order to improve the electrical characteristics of the capacitor. Specifically, the layer thickness is preferably about 0.001 μm to 0.5 μm, more preferably about 0.005 μm to 0.3 μm, and particularly preferably about 0.01 μm to 0.2 μm.

  Further, by adopting Ti, Ti—W, Hf, Nb, and Zr as a metal constituting the outer metal-containing layer (second layer) in a metal other than Ni, the same effects as Ni can be achieved.

  As described above, in the present invention, in configuring the end face electrode, among the various metals constituting the first layer and the second layer, in particular, the metal-containing portion (first layer) directly joined to the internal electrode. By using Cr, the adhesion strength between the element and the terminal electrode can be increased, and by using Ni or Ni-V as a barrier layer for the outer metal-containing layer (second layer) formed outside the first layer, the intermetallic The effect of the barrier layer against the diffusion of moisture and the infiltration of moisture can be expected, and a capacitor with good electrical characteristics and high reliability can be provided.

  Further, in the present invention, in particular, the first layer of the end face electrode is constituted by Cr sputtering, the second layer is constituted by Ni-V sputtering, the third layer is constituted by a conductive resin layer, and By constituting the layer with an Sn plating layer, an end face electrode of a PLM capacitor having particularly excellent characteristics can be obtained.

  In the end face electrode having this configuration, the conductive resin layer can function as a buffer layer, so that the durability of the end face electrode of the PML capacitor can be further improved.

  In another embodiment of the present invention, a third layer of a sputtered metal-containing layer may be formed outside the Ni-V sputtered layer. An example of the third layer metal species is Cu. Since Cu is a relatively soft metal and has good electrical conductivity, it can be used as a buffer layer by forming a thick sputtering layer (0.1 μm to 5.0 μm). In particular, in the case where the conductive resin layer is not formed outside the Ni-V sputtering layer, in addition to the effect of the Cu sputtering layer as a buffer layer, the characteristic that solder is easily attached can be utilized.

  In other embodiments of the present invention, in the case of using a metal other than Cu, by using Mo or Ni—Cu in the third layer, the same operational effects, ease of plating, ease of soldering, and the like can be achieved. .

  In an embodiment of the present invention, electrical characteristics are improved by providing a plating layer, particularly a Ni plating layer, between the sputtered metal-containing layer and the conductive resin layer. This is because the metal-containing layer formed by sputtering It is considered that this is because the conductive resin layer is well connected, and the electrical resistance between the layers is thereby reduced. However, in order to implement this method for PML capacitors, there are problems such as the presence of halogen in the plating solution and residual plating solution. Necessary.

  The present invention is characterized in that a multilayer metal-containing layer is continuously formed in a vacuum by sputtering, and this allows the surface to be exposed to the air atmosphere each time each sputtering metal-containing layer is formed. Depending on the type of metal that is formed, electrical / mechanical contact between the metal-containing layers is continuously performed in a vacuum due to the formation of a thick oxide film on the surface, adverse effects of moisture in the atmosphere, and adhesion of organic substances. It is possible to avoid the disadvantage of being worse than the case.

  As described above, it is considered that Cr and Ni exhibit adhesion and barrier properties by a certain degree of oxidation effect. However, the characteristics of continuous sputtering in vacuum with the same apparatus were actually better than when exposed to the air atmosphere each time. For this reason, even in vacuum continuous sputtering, there is a slight amount of oxygen in the vacuum chamber, and the slight oxidation (or little oxidation) resulting in the advantage of Cr and Ni, while the sputter metal Once the surface is exposed to the atmosphere, Cr or Ni is considered to form an excessive oxide film on the surface, or to deteriorate the adhesion and contact with the next sputtered metal-containing layer due to the influence of moisture and organic matter.

  That is, by exposing each sputtered metal to the atmosphere each time, a metal that is relatively easily oxidized, such as Cr or Ni, is likely to have an oxide film that is thicker than necessary, leading to a poorer nature. .

  In the present invention, when the end face is further processed by plasma treatment containing at least oxygen, the dielectric material that is a resin is scraped faster than the internal electrode that is a metal, so that the end face is uneven and the internal electrodes are exposed much. . By sputtering the metal on the rough end face, metal particles can enter the inside of the irregularities, and a capacitor with better adhesion strength and characteristics can be provided.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

Example 1
[Manufacture of PML chip capacitors]

First, using the apparatus shown in FIG. 1, a sheet in which a dielectric layer and an internal electrode layer are laminated as shown in FIG. 2 is formed, and then this sheet is cut and strips as shown in FIG. A ₁ was obtained. After forming the end surface electrode on the cut surface of the strip A _1, to obtain a chip capacitor B shown in FIG. 5 was cut into chips. The inside of the vacuum chamber 1 in FIG. 1 is maintained at about 10 ⁻⁵ Torr (1.33 × 10 ⁻³ Pa), and the drum 2 keeps its outer peripheral surface cooled to 0 ° C.

  As the dielectric material, a radiation-polymerizable monomer, here 1,6-hexanediol diacrylate, is vaporized in the resin monomer evaporation chamber 4 and is continuously rotated at a speed of 100 m / min. The resin monomer spray nozzle 3 was uniformly deposited on the outer peripheral surface. Next, the monomer deposited on the drum 2 was cured by irradiation with an electron beam to form a dielectric layer.

  Next, an internal electrode layer made of metal was formed on the dielectric layer. Aluminum was used as the internal electrode layer material. As a method for this, aluminum was heated and evaporated with a metal evaporation source 7 disposed below the rotating drum, and this was evaporated onto the dielectric layer through a metal mask 6 for electrode patterning. The metal mask 6 for patterning the internal electrode layer is moved in the direction perpendicular to the moving direction of the outer peripheral surface of the drum every time the drum 2 rotates once. As a result, as shown in FIG. 2, the pattern of the internal electrode layer could be formed for each layer. In addition, as a patterning formation method of the internal electrode layer, an oil pattern formation method generally used for manufacturing a conventional metal vapor deposition film may be used.

  The above operation was repeated about 2000 times by continuously rotating the drum 2 to form a laminate in which dielectric layers and internal electrode layers were alternately laminated. In addition, only the resin layer was laminated on the first 50 layers and the last 50 layers. The thickness per layer was about 1.0 μm for the dielectric layer and about 0.02 μm for the internal electrode metal-containing layer made of aluminum.

Next, after cutting and removing the laminate formed on the drum surface as described above, the laminate is pressed while being heated, so that a flat dielectric layer and internal electrodes as shown in FIG. A sheet in which layers were alternately laminated was obtained. This was cut along the cut surface a to obtain a strip A ₁ shown in FIG. Techniques for forming such a laminate are disclosed in US Pat. No. 5,097,800 and US Pat. No. 5,125,138.

Next, using an oxygen plasma processing apparatus, the end face 3a of the obtained strip A ₁ is brought into contact with the plasma generated from the mixed gas of oxygen and CF ₄ to selectively remove the dielectric layer. the inner electrode layer is exposed from the end face 3a, as shown in, to obtain a plasma processing strip a _2. The oxygen plasma treatment was performed at a dielectric removal rate of 0.125 μm / min for 240 minutes so that the dielectric layer was retracted about 30 μm from the end face. These oxygen plasma treatment methods are disclosed in Japanese Patent No. 1831126.

  After the oxygen plasma treatment, a metal-containing layer that becomes a part of the end face electrode was formed on the end face 3a by sputtering. In Example 1, three metal-containing layers by sputtering were formed in the order of Cr, Ni-V, and Cu. Sputtering was performed continuously in a vacuum using a magnetron system with high frequency (RF: 13.56 MHz) discharge.

Table 1 shows the sputtering conditions for each metal of Example 1 and the thickness of each metal-containing layer formed.

Next, a conductive paste in which copper particles are dispersed in a thermosetting resin is applied to the surface of the metal-containing layer formed by sputtering, heat-cured, and the outermost electrode layer on the conductive paste layer. As a result, an Sn plating layer was formed by electrolytic plating. Thereafter, the strip A ₁ was cut at a position corresponding to the cut surface b in FIG. 3 to obtain a chip capacitor B as shown in FIG.

  The obtained chip capacitor B had a thickness in the stacking direction of about 2.0 mm, a depth of about 5.0 mm, and a width (direction between the electrodes on both ends) of about 5.7 mm.

(Example 2)
In the same manner as in Example 1, after obtaining the strip A ₂ whose end face 3a was treated with plasma containing oxygen, a metal-containing layer by sputtering was continuously applied to the end face 3a in a vacuum in Ti, Ni-V, Cu. Three layers were formed in this order. Table 2 shows the Ti sputtering conditions and the thickness of the formed metal-containing layer. The sputtering conditions for Ni-V and Cu were the same as in Example 1.

  Thereafter, a conductive paste layer and an Sn plating layer were formed by the same method as in Example 1 to obtain a chip capacitor B as shown in FIG.

(Example 3)
After obtaining the strip A ₂ whose end face 3a was treated with the plasma containing oxygen by the same method as in Example 1, the metal-containing layer by sputtering was continuously formed in the order of Ta, Ni—V, and Cu in vacuum. Three layers were formed. Table 3 shows the Ta sputtering conditions and the thickness of the formed metal-containing layer. The sputtering conditions for Ni-V and Cu were the same as in Example 1.

  Thereafter, a conductive paste layer and an Sn plating layer were formed by the same method as in Example 1 to obtain a chip capacitor B as shown in FIG.

Example 4
In the same manner as in Example 1, after obtaining the strip A ₂ whose end face 3a was treated with the plasma containing oxygen, the metal-containing layer by sputtering was continuously formed in the order of Cr, Ti—W, Cu in vacuum. Three layers were formed. Table 4 shows the Ti-W sputtering conditions and the formed metal-containing layer thickness. The sputtering conditions for Cr and Cu were the same as in Example 1.

  Thereafter, a conductive paste layer and an Sn plating layer were formed by the same method as in Example 1 to obtain a chip capacitor B as shown in FIG.

(Example 5)
After obtaining the strip A ₂ whose end face 3a was treated with plasma containing oxygen by the same method as in Example 1, the metal-containing layer was continuously formed in a vacuum by sputtering under the same conditions as in Example 1 to form Cr, Ni. Three layers were formed in the order of -V and Cu. Next, a Ni plating layer having a thickness of about 5 μm was formed on the outside of the metal-containing layer by electrolytic Ni plating.

  Thereafter, a conductive paste layer and an Sn plating layer were formed by the same method as in Example 1 to obtain a chip capacitor B as shown in FIG.

(Comparative Example 1)
In the same manner as in Example 1, after obtaining the strip A ₂ whose end face 3a was treated with plasma containing oxygen, three metal-containing layers by sputtering were formed in the order of Cr, Ni—V, and Cu. However, every time the sputtering of one metal-containing layer was completed, the strip was exposed to the air atmosphere, and then the next sputtering was performed.

  Thereafter, a conductive paste layer and an Sn plating layer were formed by the same method as in Example 1 to obtain a chip capacitor B as shown in FIG.

(Comparative Example 2)
In the same manner as in Example 1, after obtaining the strip A ₂ whose end face 3a was treated with plasma containing oxygen, the end face 3a was formed of Al / Al which is generally used as an end face electrode material of a conventional film capacitor. A 50/50% alloy of Zn was sprayed (arc sprayed) to form part of the end face electrode. Its thickness was about 200 μm. Thereafter, a conductive paste layer and a Sn plating layer were formed on the surface of the metal sprayed layer in the same manner as in Example 1, and cut to obtain a chip capacitor B.

  The obtained chip capacitor B had a thickness in the stacking direction of about 2.0 mm, a depth of about 5.0 mm, and a width (direction between the electrodes on both ends) of about 5.8 mm.

※表の端面電極金属の外側には各条件とも導電性樹脂層とＳｎめっきが施されている。 [Comparison of initial electrical characteristics]
For each of the chip capacitors B obtained in Examples 1 to 5 and Comparative Examples 1 and 2, the electrical characteristics were measured and compared 10 times each. Table 5 shows the average electrical characteristics of 10 capacitors. In addition, FIG. 6 shows the variation in electrical characteristics of each of the 10 capacitors as graph 1.

* A conductive resin layer and Sn plating are applied to the outside of the end face electrode metal in the table under each condition.

  Comparing the initial electrical characteristics of the chip capacitors made under each condition, the connection part of the internal electrode metal-containing layer and the external electrode was formed by sputtering, and the sputtering metal-containing layer was continuously performed in a vacuum. Nos. 1 to 5 had small variations compared to Comparative Examples 1 and 2, and exhibited good electrical characteristics.

  When Example 1 and Example 5 having the same sputtered metal-containing layer are slightly compared, Example 5 having a Ni plating layer outside the sputtered metal-containing layer has better electrical characteristics. This is because the connection between the layers is improved by forming the Ni plating layer between the outermost layer of the metal-containing layer by sputtering and the conductive resin layer formed outside thereof.

  On the other hand, in Comparative Example 1 in which the end face electrode was formed by exposing the metal-containing layer to the atmosphere once each sputtering was completed, the terminal electrode was continuously sputtered in the same metal species / layer order in vacuum. Compared with Example 1, the electrical characteristics were poor. This is because the surface of each sputtered metal-containing layer is exposed to the atmosphere, so that an extra oxide film is formed, which is affected by moisture and organic matter in the atmosphere. This is thought to be due to poor mechanical and mechanical contact.

  Further, in Comparative Example 1 in which the connection portion between the internal electrode metal-containing layer and the external electrode is formed by metal spraying (metallicon) generally used in conventional film capacitors, tan δ and The value of ESR was very large.

  One of the causes of such a result is considered to have occurred in the metal-containing layer of the end face electrode in contact with the internal electrode layer because the metal particle diameter was smaller than the metal spraying in the electrode formation by sputtering. That is, for an element formed by alternately laminating a resin layer and a metal-containing layer as in this example, the resin layer has a smaller thickness and a smaller metal particle diameter is caused by plasma containing oxygen. This is because metal particles uniformly enter the periphery of the exposed electrode layer and on the receding dielectric layer located deep in the interlayer.

[Comparison and appearance of electrical characteristics after reflow]
Ten chip capacitors obtained in Examples 1 to 5 and Comparative Examples 1 and 2 in which the electrical characteristics were compared as described above were mounted on the printed wiring board by reflow soldering. Table 6 shows the electrical characteristics of each chip capacitor after being mounted on the printed wiring board. In addition, FIG. 7 shows the variation in characteristics of each of the 10 capacitors as a graph 2. Moreover, in order to make it easy to see the variations of the values (a), (b), and (c) of the electrical characteristic graph 2 after reflow in FIG. 7, each scale is enlarged and shown in FIG.

In addition, the chip capacitor after reflow was inspected by appearance for peeling phenomenon of the capacitor element and the end face electrode due to thermal stress of reflow, floating from the printed circuit board, and other trouble phenomena caused by general reflow soldering. Table 6 shows the number of appearance defects for the results.

  In the chip capacitors of Examples 1 to 5, there was almost no deterioration in electrical characteristics due to reflow, and the variation in capacitance after reflow was as small as ± 5%. The appearance was all normal.

  Moreover, although the chip capacitor of Comparative Example 1 had a slight deterioration in electrical characteristics due to reflow compared with the Example, all of the ten capacitors had no mounting failure and the appearance was normal. The variation in capacitance was within ± 10%.

  On the other hand, in the chip capacitor of Comparative Example 2, peeling occurred between the end face electrode and the capacitor element in 7 out of 10 elements in the appearance inspection after reflow. In these elements, the electrical connection between the printed wiring board and the capacitor is poor, and the electrical characteristics after mounting cannot be obtained. Among the chip capacitors of Comparative Example 2, those having no abnormality in the appearance inspection after mounting also showed very large values of tan δ defect and ESR, and a large deterioration in electrical characteristics was observed. This is because although the mounting failure did not occur, the electrical connection between the internal electrode layer and the end face electrode was partially defective and adversely affected the electrical characteristics of the capacitor.

[End electrode tensile strength test]
Ten chip capacitors of Examples 1 to 5 and 10 of each of Comparative Examples 1 and 2 were tested for tensile strength of end face electrodes. The test method was performed according to JIS C 0051 (Test Ua ₁ ). A lead wire was vertically attached to the formed end face electrode portion with solder, pulled with a push-pull gauge, and the strength until peeling was measured. Graph 3 (FIG. 9) shows the result. As a result, the tensile strength of each of Examples 1 to 5 having end face electrodes by sputtering was 20 N or more of JIS standards. Moreover, the peeled location was the interface between the copper sputtering layer and the conductive resin layer in Examples 1 to 4, and the interface between the Ni plating layer and the conductive resin layer in Example 5.

  Further, in Comparative Example 1 in which the end face electrode was formed by exposing the metal-containing layer to the atmosphere once each sputtering was completed, the average value of the tensile strength was about 17.7 N, which is a lower value than Examples 1-5. It became.

  On the other hand, the ten tensile strengths of Comparative Example 2 having end face electrodes by metal spraying were below the JIS standard. The average value of tensile strength was about 4.5N. The peeled portion was the interface between the capacitor element end face and the layer formed by metal spraying.

[Comparison]
The initial electrical characteristics of the chip capacitors of Examples 1 to 5 were good and small in variation, and provided small and large capacity capacitors.

  First, when Examples 1 to 4 were compared, there was no significant difference depending on the type of metal to be sputtered, and the overall characteristics were good. In the present embodiment, an example of only a specific metal is given, but the metal species to be sputtered is not limited.

  For the first layer (lowermost layer) of the end face electrode directly connected to the internal electrode metal-containing layer, it is possible to use Mo, W, Ni—Cr, etc. in addition to Cr, Ti, Ta mentioned in this embodiment. A highly reliable chip capacitor with good connection between the metal-containing layer and the end face electrode can be obtained.

  Even in the second layer of the end face electrode, in addition to Ni-V and Ti-W mentioned in the present embodiment, even if metals such as Ti, Ni, Zr, Nb, and Hf are used, diffusion between metal-containing layers and from the outside Thus, it is possible to provide a chip capacitor that has a good characteristic and high reliability, acting as a barrier layer, for example, preventing moisture from entering.

  Further, in the present embodiment, Cu is used for the third layer of the sputtering metal-containing layer of the end face electrode, but Ni, Mo, Ni—Cu, or the like may also be used. The third layer of the sputtering metal-containing layer is a metal-containing layer mainly for improving the plating of solder, Sn, or the like. Therefore, when the conductive resin layer is formed outside the sputtering metal-containing layer, the third layer may not be provided. However, when it is desired to increase the thickness of the sputtered metal-containing layer, the third layer may be formed of a metal having a small specific resistance such as Cu.

  Further, when Examples 1 and 5 are compared, Example 5 in which an Ni plating layer is formed between the metal-containing layer formed by sputtering and the conductive resin layer formed on the outside thereof is slightly more. However, the electrical characteristics were good. This is because the Ni plating layer improves the connection between the metal-containing layer formed by sputtering and the conductive resin layer, thereby reducing the electrical resistance between the layers.

  Next, comparison is made between the chip capacitor of Example 1 in which sputtering was performed in the same metal species and layer sequence in vacuum and Comparative Example 1 in which the surface of the metal-containing layer was once exposed to the atmosphere after each sputtering. Then, the chip capacitor of Comparative Example 2 was inferior in both electrical characteristics and tensile strength as compared with Example 1. This is because the surface of each sputtered metal-containing layer is exposed to the atmosphere, an extra oxide film is formed, or it is affected by moisture and organic substances in the air, so that・ This is thought to be due to poor mechanical contact.

  On the other hand, the initial electrical characteristics of the chip capacitor shown in Comparative Example 2 varied greatly, and the electrical characteristics were greatly inferior even when compared with the chip capacitors of Examples 1 to 5. This is presumably because in the metal-containing layer of the end face electrode in contact with the internal electrode layer, the electrode formation by sputtering has a smaller metal particle diameter than metal spraying. That is, for the element formed by alternately laminating the resin layer and the metal-containing layer in the vacuum as in this example, the metal layer diameter is small because the thickness of the resin layer is small and the adhesion between the layers is strong. On the other hand, the metal particles uniformly enter the periphery of the electrode layer exposed by the plasma containing oxygen and the recessed dielectric layer located deep in the interlayer. As a result, the adhesion strength between the element and the end face electrode is improved, and a reliable capacitor having excellent electrical characteristics can be obtained. In this example, the thickness of the dielectric layer was set to 1 μm. However, in the case of a chip capacitor in which the thickness of the dielectric layer is made thinner than 1 μm, the edge electrode formation method by sputtering is more advantageous for the reasons described above. Increase. Also, in the end face electrode forming method by metal spraying, the molten metal particles collide with the end face electrode terminal forming face of the capacitor element to form the end face electrode, and therefore the internal electrode layer exposed on the end face is cut or bent by the pressure. Resulting in. For this reason, the adhesion strength between the end face electrode and the capacitor element is lowered, which adversely affects the electrical characteristics of the capacitor. From the results of the tensile strength test of the end face electrode, it was found that the electrode forming method by sputtering is more suitable for the electrode forming method by metal spraying in the element formed by alternately laminating the resin layer and the metal-containing layer as in this example. It was found that the adhesion strength with the capacitor element was superior.

FIG. 1 is a schematic view of a laminate manufacturing apparatus according to the present invention. FIG. 2 is a perspective view including a side surface of a laminated (body) sheet (strap) composed of a dielectric layer and an internal electrode metal-containing layer. FIG. 3 is a perspective view including a cut surface of the strip A ₁ cut from a laminated (body) sheet composed of a dielectric layer and an internal electrode metal-containing layer. FIG. 4 is a perspective view of the strip A _{2 in} a state where the plasma treatment is performed on one side of the cut surface of the strip A ₁ cut from the laminated (body) sheet composed of the dielectric layer and the internal electrode metal-containing layer. is there. FIG. 5 shows an end face electrode formed by sputtering according to the present invention on one side of a cut surface of a strip A ₁ cut from a laminated (body) sheet composed of a dielectric layer and an internal electrode metal-containing layer. It is a schematic diagram of manufactured chip capacitor B. FIG. 6 is a graph 1 showing variations in electrical characteristics of each of the chip capacitors of Examples 1 to 5 and the chip capacitors of Comparative Examples 1 and 2 corresponding to Table 5. FIG. 7 is a graph 2 showing variation in electrical characteristics after reflow of each of the chip capacitors of Examples 1 to 5 and the chip capacitors of Comparative Examples 1 and 2 corresponding to Table 6. FIG. 8 is an enlarged view corresponding to each of (a) to (c) of FIG. 7 in which the variation in the electrical characteristics (graph 2) after reflow shown in FIG. FIG. 9 is a graph 3 showing the test results of the tensile strength of the end face electrodes for each of the chip capacitors of Examples 1 to 5 and the chip capacitors of Comparative Examples 1 and 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Drum 3 Resin monomer spray nozzle 4 Resin monomer evaporation chamber 5 Electron gun 6 Metal mask 7 Metal evaporation source 8 Metering monomer supply tube 9 Vaporized monomer 10 Electron beam A Laminated sheet (strip)
A ₁ Laminated sheet (strip)
Laminated sheet (strip) after A ₂ plasma treatment
B Chip capacitor a, b Longitudinal and lateral cutting lines 3a Strip end face X Dielectric layer Y Internal electrode metal layer Z End face electrode

Claims (18)

Capacitor having a capacitor element manufactured by alternately laminating a resin thin film layer serving as a dielectric layer and an internal electrode metal-containing layer by vacuum deposition in vacuum, and an electrode provided on the end face In
The resin thin film layer is formed of an acrylic resin,
The electrode provided on the end face includes a metal-containing portion formed by sputtering , and the metal-containing portion formed by sputtering includes Al, Ti, V, Cr, Ni, Cu, Zn, Zr, and Nb. , Mo, Hf, Ta and W selected from the group consisting of a simple substance, an oxide of the metal, or a compound other than the oxide of the metal, or Al, Ti, V, Cr, Ni , Cu, Zn, Zr, Nb, Mo, Hf, an alloy containing at least one selected from the group consisting of Ta, and W, an oxide of the alloy, or a compound other than the oxide of the alloy Consists of
At least part of the metal-containing portion formed by the sputtering is directly bonded to the internal electrode metal of the capacitor element, and the metal or alloy of the metal-containing portion formed by sputtering directly bonded to the internal electrode is Ti. , Cr, Mo, Ta, W and a capacitor selected from the group consisting of Ni—Cr . 2. The capacitor according to claim 1 , wherein the metal-containing portion formed by the sputtering is formed as a single layer or a plurality of layers of the same component metal or different components . Ti, Ni, Zr, Nb, Hf, Ta, Ni-V and at least a part of the metal-containing part formed by sputtering and outside the metal-containing part directly joined to the internal electrode metal of the capacitor element capacitor according to claim 1 or 2, characterized in that it has an outer metal-containing layer made of any one metal or alloy selected from the group consisting of Ti-W. Any one of a metal or an alloy selected from the group consisting of Ni, Cu, Mo, and Ni-Cu, which is at least a part of the metal-containing portion formed by the sputtering and further outside the outer metal-containing layer. The capacitor according to claim 3 , further comprising an outer covering metal-containing layer made of seeds. Besides, the capacitor according to any one of claims 1 to 4, characterized in that a conductive resin layer on the end face electrode of the metal-containing portion formed by the sputtering. Other metal-containing portion formed by the sputtering, electroless plating on an end surface electrode, electroless plating, claim 1, characterized in that it comprises a metal-containing layer formed by at least one method for hot dipping of 5 The capacitor according to any one of the items. The capacitor according to claim 6 , further comprising a metal-containing layer formed by Ni plating on the outside of the metal-containing portion formed by the sputtering. 6. The capacitor according to claim 5 , wherein the electrode provided on the end face is composed of a metal-containing portion formed by sputtering and a conductive resin layer outside the metal-containing portion. Electrodes provided on the end face, according to claim 6, characterized in that it is constituted by the inner metal-containing moiety is formed by sputtering in this order, a conductive resin layer, and a metal-containing layer formed by plating Capacitor. The sputtering, magnetron sputtering method, two-pole sputtering method, an ion beam sputtering method, triode sputtering method according to claim 1 to 9, characterized in that it is performed by at least one selected from the group of and 4-pole sputtering method The capacitor according to any one of the items. Metal-containing portion of the electrode formed by the sputtering, any sputtering from claim 1 characterized by comprising a plurality of metal-containing layer formed by a plurality of times in succession in a vacuum 10 one Capacitor according to item. The capacitor according to any one of claims 1 to 11 , wherein the end surface of the capacitor is surface-treated with plasma before the electrode is formed on the end surface of the capacitor. The capacitor according to claim 12 , wherein the plasma is generated from a gas containing at least oxygen. The capacitor element is a dielectric composed of a resin thin film layer and a metal selected from the group consisting of Al, Zn, Cu, Ag and Ni, a metal oxide thereof, or a metal compound other than these metal oxides, or It is characterized by being formed by alternately laminating a plurality of internal electrode metal-containing layers made of an alloy containing at least one of these metals, an oxide of the alloy, or a compound other than the oxide of the alloy. The capacitor according to any one of claims 1 to 13 . The capacitor according to any one of claims 1 to 14 , wherein the resin thin film layer is made of any one of a radiation curable resin, an ultraviolet curable resin, and a thermosetting resin. A method of manufacturing a capacitor according to claim 1,
A capacitor element is formed by alternately laminating a resin thin film layer serving as a dielectric layer and an internal electrode metal-containing layer by vacuum deposition in vacuum, and a metal-containing portion formed by sputtering on the end face of the capacitor element A method for manufacturing a capacitor, comprising forming an end face electrode including: 17. The capacitor according to claim 16 , wherein the metal-containing portion formed by sputtering is formed by forming a plurality of layers with the same component metal or by forming a plurality of layers with metals having different components . Production method. Claim 16 characterized in that it constitutes by laminating an electrode provided on the end face, sequentially from the inside, the metal containing moiety is formed by sputtering, a conductive resin layer, and a metal-containing layer formed by plating Or the method for producing a capacitor according to 17 .

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