WO2011162218A1

WO2011162218A1 - Laminate of ceramic insulation layer and metal layer, and method for producing laminate

Info

Publication number: WO2011162218A1
Application number: PCT/JP2011/064083
Authority: WO
Inventors: 直彦阿部
Original assignee: 三井金属鉱業株式会社
Priority date: 2010-06-21
Filing date: 2011-06-20
Publication date: 2011-12-29
Also published as: TW201210809A; JP2012000947A

Abstract

Provided are a laminate of a ceramic insulation layer and a metal layer and also a method for producing this laminate, with which it is possible to appropriately select structural materials for the metal layer, which serves as a base material, regardless of the method used to form the ceramic insulation layer, with which deterioration of the base material and reduction in insulating performance of the insulation layer during the ceramic insulation layer production process can be prevented, and with which an improved production yield can be achieved. A laminate (100) of a ceramic insulation layer (30) and a metal layer (10), wherein a protective layer (20) is provided on the surface of the side of the metal layer (10) on which the ceramic insulation layer (30) is formed, and the protective layer (20) is formed from a silicon compound having a layer thickness of 5 nm to 100 nm.

Description

LAMINATE OF CERAMIC INSULATION LAYER AND METAL LAYER AND METHOD FOR PRODUCING THE LAMINATE

This invention relates to the laminated body of a ceramic type insulating layer and a metal layer, and the manufacturing method of the said laminated body. In particular, the laminated body of the ceramic insulating layer and the metal layer is an electronic circuit forming material for forming various electronic circuits including a capacitor circuit or a transistor circuit on a printed wiring board or a semiconductor substrate, or a capacitor or a transistor. It can be suitably used as an electronic component forming material for forming various electronic components.

Conventionally, along with the enhancement of functionality and performance of portable electronic devices such as mobile phones, light and thin printed wiring boards using high-density mounting technology have progressed. Specifically, as a high-density mounting technology, miniaturization and thinning of surface mounting components, high definition of wiring patterns, thinning and multilayering of wiring boards, and the like have been adopted.

However, when the wiring pattern becomes high definition and the wirings come close to each other, complicated wiring routing leads to an increase in parasitic resistance, which causes signal delay, heat generation, unnecessary radiation, crosstalk, and the like. For this reason, in order to cope with high-frequency circuits and ultrahigh-speed operation circuits, the high-density mounting technology alone is approaching its limit.

In response to such a flow, in recent years, electronic components such as capacitors and resistors are formed on the inner layer of a multilayer wiring board by a wiring pattern or the like at the manufacturing stage of the printed wiring board. By embedding electronic components in a printed wiring board, for example, electronic components such as capacitors can be arranged directly under active elements such as ICs, and the wiring length between electronic components can be shortened to the limit and wiring can be simplified. It becomes possible. For this reason, increase in parasitic resistance can be suppressed, signals can be transmitted and received between components at higher speed, and generation of heat generation, unnecessary radiation, crosstalk, and the like can be suppressed. Further, along with the reduction in the number of surface-mounted components and the shortening of the wiring length, the printed wiring board can be further reduced in thickness and thickness. Therefore, it is considered that the demand for such a printed wiring board with built-in electronic components will further increase in the future in the realization of portable electronic devices and the like that require further advanced processing.

Further, in semiconductor circuit components mainly made of silicon such as CMOS transistors, the use of so-called metal gate electrodes as gate electrodes and the use of ceramic insulating materials as gate insulating films are being studied. In response to such a flow, in recent years, it has been proposed to form a gate electrode or a gate insulating film using a laminate in which a ceramic insulating layer is laminated on a metal foil. That is, in the production of various electronic circuit components including semiconductor circuit components, and various electronic circuit formations including semiconductor circuits, which have been inevitable in the past by using a high vacuum process, a web-like Application of printing and etching techniques used in the production of printed wiring boards using the above-mentioned base materials has been performed.

From the above viewpoint, the present applicants, as disclosed in Patent Document 1 and Patent Document 2 as one of the circuit forming materials, have an insulating layer or a dielectric layer on a metal foil as a conductive layer. Capacitor circuit forming materials have been proposed that have a basic structure of laminated ceramic insulating layers.

JP 2007-35975 A No. 2008/044573

Incidentally, the capacitance of the capacitor increases as the dielectric constant of the dielectric layer increases. Furthermore, when the electrode area is the same, the capacitance becomes larger as the distance between the electrodes is shorter. That is, in order to obtain a capacitor having a large capacitance, a laminate of a ceramic insulating layer and a metal layer in which a ceramic insulating layer and a metal layer having a high dielectric constant are stacked is required. Further, along with miniaturization of semiconductor integrated circuits, miniaturization of transistor circuits and thinning of gate insulating films are required. Therefore, it is required to form a ceramic insulating layer used as a dielectric layer or an insulating layer thin on a conductive layer and in a wide area.

However, conventionally, various methods such as sol-gel method, electrophoretic electrodeposition, MOCVD method, sputtering deposition and the like have been adopted for forming the ceramic insulating layer. There is a high temperature process. In particular, in the sol-gel method, a high temperature is applied to the metal layer as a base material during firing, and the metal layer is oxidized to cause deterioration of the base material, or the constituent metal of the metal layer diffuses into the ceramic insulating layer. As a result, the insulating property is lowered, and the reliability is sometimes lowered.

For this reason, considering the influence of heat applied to the conductive layer when forming the ceramic insulating layer, the metal material forming the conductive layer has low electrical resistivity and heat resistance. It was necessary to select a material that can withstand a high temperature process. In other words, from the viewpoint of electrical resistivity, there is a case where copper cannot be adopted when it is necessary to go through a high temperature process even though copper is superior.

From the above, in the market, the constituent material of the metal layer used as the base material can be selected as appropriate regardless of the method of forming the ceramic insulating layer. There has been a demand for improvement in production yield by preventing a decrease in insulating properties of the insulating layer.

Therefore, as a result of diligent research, the present inventors can appropriately select a metal material for forming a conductive layer regardless of a method for forming a ceramic insulating layer, and obtain a capacitor circuit having stable capacitor characteristics. The present inventors have devised the following invention of a laminate of a ceramic insulating layer and a metal layer and a method of manufacturing the laminate, which can improve the production yield and obtain a highly reliable circuit forming material. .

A laminate of a ceramic insulating layer and a metal layer according to the present invention is a laminate of a ceramic insulating layer and a metal layer, and the metal layer has a surface on the side where the ceramic insulating layer is provided. Further, a protective layer made of a silicon compound having a layer thickness of 5 nm to 100 nm is provided.

In the laminate of the ceramic insulating layer and the metal layer according to the present invention, the protective layer is preferably made of an amorphous silicon compound.

The method for producing a laminate of a ceramic insulating layer and a metal layer according to the present invention includes a protective layer forming step of forming a protective layer made of a silicon compound having a layer thickness of 5 nm to 100 nm on the upper surface of the metal layer, And a ceramic insulating layer forming step of forming the ceramic insulating layer on the surface of the protective layer.

According to the present invention, in the laminate of the ceramic insulating layer and the metal layer, a protective layer made of a silicon compound having a layer thickness of 5 nm to 100 nm is provided on the side of the metal layer on which the ceramic insulating layer is provided. I have. By having such a configuration, the ceramic insulating layer is formed on the upper surface of the metal layer through a high-temperature process such as firing in the course of manufacturing by various methods such as a sol-gel method, a sputtering method, a CVD method, and an electrophoretic electrodeposition method. In the case of forming the metal layer, the oxidation of the metal layer can be extremely effectively prevented, the decrease in the conductivity of the metal layer as the conductive layer and the deterioration of the mechanical characteristics can be prevented. Adhesion with the system insulating layer is improved. At the same time, by adopting this configuration, the protective layer acts as a barrier, preventing the metal constituting the metal layer from precipitating and diffusing into the ceramic insulating layer, thereby reducing the insulating properties of the ceramic insulating layer. And the deterioration of dielectric characteristics can be prevented, and the laminate can be provided as a highly reliable electronic circuit forming material or electronic circuit component forming material.

Further, conventionally, depending on the method of forming the ceramic insulating layer, even if copper or copper alloy having a lower electrical resistivity cannot be adopted as the metal layer because of considering heat resistance, copper or copper An alloy or the like can be used as the metal layer. Therefore, according to the present invention, the metal material for forming the conductive layer can be appropriately selected regardless of the method for forming the ceramic insulating layer, and a capacitor circuit having stable capacitor characteristics can be obtained and produced. The yield can be improved and a highly reliable circuit forming material can be obtained.

It is a schematic diagram which shows the basic layer structure of the laminated body of the ceramic type | system | group insulating layer which concerns on this invention, and a metal layer. SEM photograph (a) showing the surface of the ceramic insulating layer in the laminate of the ceramic insulating layer and the metal layer of Example 1, SEM photograph (b) showing the surface of the ceramic insulating layer of Example 2, comparison It is the SEM photograph (c) which shows the surface of the same ceramic type | system | group insulating layer of Example 1, and the SEM photograph (d) which shows the surface of the same ceramic type | system | group insulating layer of the comparative example 2. SEM photographs (a) and (b) showing the cross section of the laminate of the ceramic insulating layer and metal layer of Example 1, and SEM photographs showing the cross section of the laminate of the ceramic insulating layer and metal layer of Comparative Example 1 (C), (d). SEM photographs (a) and (b) showing the cross section of the laminate of the ceramic insulating layer and metal layer of Example 2, and SEM photographs showing the cross section of the laminate of the ceramic insulating layer and metal layer of Comparative Example 2 (C), (d). It is a graph which shows the X-ray-diffraction result of the surface of the ceramic type | system | group insulating layer of the laminated body of the ceramic type | system | group insulating layer of Example 1 and Example 2, and a metal layer. It is a graph which shows the X-ray-diffraction result of the surface of the ceramic type | system | group insulating layer of the laminated body of the ceramic type | system | group insulating layer of Comparative Example 1 and Comparative Example 2, and a metal layer. 2 is an electron beam microanalyzer photograph of a laminate of a ceramic insulating layer and a metal layer in Example 1. FIG. 3 is an electron beam microanalyzer photograph of a laminate of a ceramic insulating layer and a metal layer of Comparative Example 1. It is a figure which shows the measurement result of the leakage current density in the laminated body of the ceramic type insulating layer of Example 1 and Comparative Example 1, and a metal layer. It is a figure which shows the measurement result of the leakage current density in the laminated body of the ceramic type insulating layer of Example 2 and Comparative Example 2, and a metal layer. In the SEM photograph (a) which shows the cross section of the laminated body of the ceramic type insulating layer and metal layer of Example 3, and the SEM photograph (b) which shows the cross section of the laminated body of the ceramic type insulating layer and metal layer of the comparative example 3. is there. It is a figure which shows the measurement result of the leakage current density in the laminated body of the ceramic type insulating layer of Example 3 and Comparative Example 3, and a metal layer. It is the figure which showed the change of the deposition amount of the dielectric particle when changing the voltage to apply, when forming a ceramic type | system | group insulating layer on the surface of a metal layer by the electrophoretic electrodeposition method.

Hereinafter, preferred embodiments of a laminate of a ceramic insulating layer and a metal layer and a method for producing the laminate according to the present invention will be described. The laminated body of the ceramic insulating layer and the metal layer according to the present invention can be used as, for example, a dielectric layer and a lower electrode forming layer of a capacitor, or a gate insulating film and a gate electrode of a transistor. It can be suitably used as an electronic circuit forming material for forming various electronic circuits on a substrate or a semiconductor substrate, or an electronic component forming material for forming various electronic components such as capacitors and transistors. . Hereinafter, 1. 1. Laminated body of ceramic insulating layer and metal layer; The manufacturing method of the said laminated body is demonstrated in order.

1. Laminated body of ceramic insulating layer and metal layer As shown in FIG. 1, a laminated body 100 according to the present invention is obtained by laminating a ceramic insulating layer 30 on the upper surface of a metal layer 10 with a protective layer 20 interposed therebetween. The protective layer 20 is characterized by adopting a layer made of a silicon compound having a layer thickness of 5 nm to 100 nm. Hereinafter, the metal layer 10, the protective layer 20, and the ceramic insulating layer 30 will be described in this order.

1-1) Metal Layer First, the metal layer 10 will be described. The metal layer 10 has conductivity, and is a layer used as, for example, an electrode formation layer. Accordingly, various metals such as copper, aluminum, nickel, cobalt, gold, and platinum, or various metals that can be employed as the conductive layer such as an alloy thereof can be appropriately selected and used.

Any of the above-listed materials can be suitably used, but it is preferable to use copper, aluminum, nickel, or an alloy thereof from the viewpoint of easy availability and low cost. Furthermore, copper or a copper alloy can be particularly preferably used because it has a low electrical resistivity and is excellent in workability during circuit formation by etching or the like.

Surface treatment layer: In the present invention, a surface treatment layer using one or more selected from nickel, zinc, chromium, or an alloy thereof may be provided on the surface of the metal layer 10. By providing the surface treatment layer between the metal layer 10 and the protective layer 20 in this way, for example, various surfaces according to the metal used for the surface treatment such as improvement of heat resistance and improvement of corrosion resistance of the metal layer 10. A processing effect can be obtained. Therefore, even when copper or a copper alloy is selected as a constituent material of the metal layer 10, by providing the surface treatment layer between the metal layer 10 and the protective layer 20, a metal layer made of copper or a copper alloy. The heat resistance, corrosion resistance, etc. of No. 10 can be improved and deterioration of the conductive layer, such as a decrease in conductivity and a decrease in mechanical properties, can be prevented. However, since the surface treatment layer has an arbitrary layer configuration, the illustration is omitted in FIG.

Silane coupling agent layer: In the laminate 100 according to the present invention, a silane coupling agent layer may be provided between the metal layer 10 and the protective layer 20. By providing the silane coupling agent layer, the wettability of the metal layer 10 can be improved and the adhesion between the metal layer 10 and the protective layer 20 can be improved. Since the silane coupling agent layer has an arbitrary layer configuration, the illustration thereof is omitted in FIG.

In the metal layer 10, when a surface treatment layer and a silane coupling layer are provided between the metal layer 10 and the protective layer 20, only one of these layers may be provided, or both layers may be provided. Good. When both the surface treatment layer and the silane coupling agent layer are provided between the metal layer 10 and the protective layer 20, the metal layer 10, the surface treatment layer, the silane coupling agent layer, and the protective layer 20 are laminated in this order. It is preferable to provide as described above. This is because the surface treatment effect of the metal layer 10 by the surface treatment layer is obtained, and the adhesion between the protective layer 20 and the metal layer 10 is obtained by the silane coupling agent layer.

1-2) Protective layer Next, the protective layer 20 will be described. As described above, the protective layer 20 is a layer made of a silicon compound and having a thickness of 5 nm to 100 nm, and the ceramic insulating layer 30 is provided on the surface of the protective layer 20. Thus, by providing the protective layer 20 made of a silicon compound with a layer thickness of 5 nm to 100 nm, for example, when the ceramic insulating layer 30 is formed on the surface of the metal layer 10, Deterioration of the metal layer 10, that is, oxidation of the various metal materials constituting the metal layer 10 can be extremely effectively prevented, and deterioration of the metal layer 10 can be prevented. Here, the thickness of the protective layer 20 is more preferably in the range of 10 nm to 70 nm. When the thickness of the protective layer 20 is in the range of 10 nm to 70 nm, the deterioration of the metal layer 10 can be more effectively prevented even when a high temperature process is performed when the ceramic insulating layer 30 is formed. can do. Further, as described later, even when a BST (Barium Strontium Titanate) layer having a perovskite structure is employed as the ceramic insulating layer 30, it prevents the highly reactive BST layer from reacting with the metal layer 10. Further, it is possible to prevent the metal constituting the metal layer 10 from being precipitated and diffused in the ceramic insulating layer 30. Therefore, by laminating the protective layer 20 according to the present invention on the metal layer 10 and providing the ceramic insulating layer 30 so as to be in contact with the protective layer 20, the conductivity of the metal layer 10 is reduced and the ceramic insulating layer is provided. It is possible to prevent the decrease in the insulation property of 30 very effectively. For this reason, in the past, in consideration of the influence of heat applied when the ceramic insulating layer 30 is formed, copper or a copper alloy could not be actively employed as described above. As described above, copper or a copper alloy can be suitably used as a constituent material of the metal layer 10. Hereinafter, this point will be further described.

As a method for forming the ceramic insulating layer 30, various methods such as a sol-gel method, an MOCVD method, a sputtering deposition method, and an electrophoretic electrodeposition method are generally employed. Conventionally, it has been necessary to appropriately select the metal constituting the conductive layer for forming the lower electrode in accordance with the method for forming the ceramic insulating layer 30. In other words, the heat applied when forming the ceramic insulating layer 30 may oxidize the metal material constituting the conductive layer and cause deterioration of the conductive layer. It was necessary to appropriately select a metal material constituting the conductive layer according to the method employed. For example, when the ceramic insulating layer 30 is formed, platinum or the like is used as a heat-resistant metal in order to prevent oxidation of the conductive layer when it is necessary to go through a high-temperature process such as a firing process in a sol-gel method or the like. It was. In addition, when using a metal foil as the conductive layer, a nickel foil or a nickel alloy foil (nickel-phosphorus alloy foil, nickel-cobalt alloy foil) or a composite foil in which a nickel layer of, for example, about 1 μm to 5 μm is laminated on a copper layer Etc. have been adopted.

Thus, conventionally, the metal material constituting the conductive layer for forming the lower electrode in the laminate 100 of the ceramic insulating layer and the metal layer is used when forming the ceramic insulating layer 30 used as a dielectric layer. Depending on the method employed, certain restrictions may be imposed on the type of metal that can be selected. For example, when copper and nickel are compared, the electrical resistivity of copper is about 1.68 × 10 ⁻⁸ Ωm, whereas the electrical resistivity of nickel is 6.99 × 10 ⁻⁸ Ωm. Copper is a nonmagnetic metal, whereas nickel is a magnetic metal. Therefore, it is easier to improve the electrical characteristics of various electronic components obtained using the laminate 100 when the metal layer 10 is made of copper, which has a low electrical resistivity and is nonmagnetic. is there. However, conventionally, when a high temperature process exists when forming the ceramic insulating layer 30, copper or copper alloy is oxidized under this high temperature process, and the above-mentioned various problems occur, so copper or copper In some cases, the alloy could not be actively employed. On the other hand, in the present invention, for example, a two-layer structure in which the metal layer 10 and the protective layer 20 are laminated as a conductive layer, and the ceramic insulating layer 30 is formed on the surface of the protective layer 20 using the conductive layer as a base material. By forming the metal layer 10, the metal layer 10 can be configured by appropriately selecting various metals including copper or a copper alloy regardless of the method of forming the ceramic insulating layer 30.

Silicon Compound: In the present invention, the protective layer 20 is preferably made of one kind selected from SiO ₂ , SiN _x —SiO ₂ (x> 0) and SiN _x (x> 0) as the silicon compound. Since the protective layer 20 made of these silicon compounds can be formed at a relatively low temperature, a heat load is not applied to the metal layer 10 when the protective layer 20 is formed, and the metal layer 10 is not oxidized. These silicon compounds are preferable because they have low reactivity with the metal layer 10 and do not react with the metal layer 10 to lower the conductivity of the metal layer 10. Further, since the protective layer 20 made of these silicon compounds is amorphous and excellent in flexibility, it is excellent in handling properties when the laminate 100 of the ceramic insulating layer and the metal layer is laminated on a substrate.

1-3) Ceramic Insulating Layer Next, the ceramic insulating layer 30 will be described. The ceramic insulating layer 30 is a layer that is used as an insulating layer or a dielectric layer when manufacturing various electronic components using the laminate 100, and is a layer made of an inorganic oxide. For example, considering the case where a capacitor circuit is formed by etching or the like using the multilayer body 100, it is preferable that the ceramic insulating layer 30 is thin. As is well known, the capacitance (C) of the capacitor can be obtained by the following equation, and is proportional to the dielectric constant and inversely proportional to the distance (d) between the electrodes, that is, the thickness of the ceramic insulating layer 30. Because.

C = εε ₀ (A / d) (formula)
In the above equation, C is the capacitance of the capacitor, ε is the dielectric constant of the ceramic insulating layer 30, ε ₀ is the vacuum dielectric constant, A is the surface area of the electrode, and d is This is the distance between the upper electrode and the lower electrode.

Thickness of the ceramic insulating layer: From the viewpoint of forming a capacitor having a large capacitance using the laminate 100 according to the present invention, or from the viewpoint of miniaturizing various electronic components such as transistors, the ceramic system according to the present invention The insulating layer 30 is preferably thinner as described above. Specifically, the thickness is preferably in the range of 50 nm to 5.0 μm, and more preferably in the range of 50 nm to 2.0 μm. If the thickness of the ceramic insulating layer 30 is less than 50 nm, the layer thickness may be non-uniform, and the upper electrode and the lower portion when the capacitor circuit is formed due to the presence of gaps between the inorganic oxide particles. This is not preferable because a short circuit may occur between the electrodes and the leakage current may increase. In addition, when the thickness of the ceramic insulating layer 30 exceeds 5.0 μm, cracks may occur in the ceramic insulating layer 30 and the capacitance is reduced when forming the capacitor circuit, which is not preferable. .

Constituent material of ceramic insulating layer: From the viewpoint of obtaining a capacitor circuit having a large capacitance, the ceramic insulating layer 30 is composed of barium titanate, strontium titanate, barium strontium titanate, strontium zirconate, zirconic acid. A perovskite ferroelectric thin layer having a basic composition such as bismuth is preferred. Among these, in particular, when the ceramic insulating layer 30 is a perovskite ferroelectric thin layer having a basic composition of any one of barium titanate, strontium titanate, and barium strontium titanate, the dielectric constant is high, This is particularly preferable from the viewpoint that a large capacity capacitor circuit can be obtained.

Impregnation of resin component: In the present invention, the ceramic insulating layer 30 is preferably impregnated with a resin component between particles or grain boundaries present in the ceramic insulating layer 30. For example, when the ceramic insulating layer 30 is formed by the sol-gel method or the electrophoretic electrodeposition method, a gap (structural defect) that becomes a flow path of a leakage current is easily generated between particles or grain boundaries in the ceramic insulating layer 30. Therefore, by impregnating a resin component between particles or grain boundaries existing in the ceramic insulating layer 30, a structural defect serving as a leakage current channel can be filled. As a result, the leakage current can be reduced, the deterioration of the insulating properties of the ceramic insulating layer 30 can be prevented, and it can function as a highly reliable insulating layer or dielectric layer, and the production yield can be improved. can do.

In addition, about the formation method of the ceramic type | system | group insulating layer 30, the resin component impregnated between the particle | grains which exist in the ceramic type | system | group insulating layer 30, or a grain boundary, the impregnation method, etc. are 2. This will be described later in the method for manufacturing the laminate 100 of the ceramic insulating layer and the metal layer.

1-4) Upper Electrode Formation Layer In the laminate 100 configured as described above, the upper electrode formation layer 40 made of a metal material is provided on the upper surface of the ceramic insulating layer 30, and the metal layer 10 (including the protective layer 20) is provided. The laminated body 100 may be configured as a capacitor circuit forming material (110) that uses the dielectric characteristics of the ceramic insulating layer. In this case, the upper electrode formation layer 40 is preferably composed of any one of copper, copper alloy, nickel, nickel alloy, and aluminum. The capacitor circuit forming material (110) thus configured can be suitably used, for example, when a capacitor circuit is formed on the inner layer of the printed wiring board by etching or the like.

2. Next, the manufacturing method of the laminated body of the ceramic type | system | group insulating layer and metal layer which concerns on this invention is demonstrated. The method for producing a laminate of a ceramic insulating layer and a metal layer according to the present invention includes a protective layer forming step of forming a protective layer 20 made of a silicon compound having a layer thickness of 5 nm to 100 nm on the metal layer 10; And a ceramic insulating layer forming step of forming the ceramic insulating layer 30 on the surface of the protective layer 20. Hereinafter, each step will be described.

2-1) Protective layer forming step In the protective layer forming step, the protective layer 20 made of the silicon compound having a thickness of 5 nm to 100 nm is formed on the metal layer 10.

Metal layer: When forming the protective layer 20, the metal layer 10 can be made of various metals such as copper, nickel, cobalt, gold, and platinum, or metal foils of these alloys, etc. In particular, copper or a copper alloy can be preferably used. As described above, copper has the lowest electrical resistivity among the above-mentioned metals and is a non-magnetic material, so that it is suitable as a conductive layer and is easily available compared to other metals. This is because processing such as etching is easy and the manufacturing cost can be kept low because it is inexpensive.

Metal foil: The metal layer 10 can be formed using a metal foil made of the various metals described above. In this case, a metal foil obtained by a rolling method or an electrolytic method can be used. For example, when forming the metal layer 10 made of copper or copper alloy, copper foil or copper alloy foil (brass foil, Corson alloy foil) can be used. Further, when forming the metal layer 10 made of nickel or nickel alloy, nickel foil or nickel alloy foil (nickel-phosphorus alloy foil, nickel-cobalt alloy foil) can be used. Moreover, you may use the composite foil etc. which provide a dissimilar metal layer on the surface of these metal foils. However, the metal layer 10 may be a single composition metal layer from the viewpoint of satisfactorily forming a fine electrode pattern or wiring pattern in consideration of, for example, performing circuit formation by etching or the like. preferable. Moreover, you may provide the said surface treatment layer and / or a silane coupling agent layer on the surface of the metal layer 10 by a conventionally well-known method as needed.

Formation of protective layer: Next, the protective layer 20 is formed on the surface of the metal layer 10 so as to have a layer thickness of 5 nm to 100 nm. However, when the surface treatment layer and / or the silane coupling layer is provided on the surface of the metal layer 10, the protective layer 20 is provided on the surface of the outermost surface treatment layer or the silane coupling material layer. Form.

In forming the protective layer 20 in the present invention, a) a method of forming a SiO ₂ layer by applying polysilazane; and b) a SiO ₂ layer, SiNx by either chemical vapor reaction (CVD) or physical vapor deposition. Any method of forming a —SiO ₂ layer and a SiNx layer may be employed.

a) Method for forming a SiO ₂ layer by applying polysilazane Polysilazane is applied within a range of 5 nm to 100 nm on the metal layer 10 provided with a surface treatment layer and / or a silane coupling agent layer as required. Apply to a thickness. As a coating method, for example, a conventionally known coating method such as a spin coating method can be appropriately employed. As the polysilazane solution, for example, SSL-SD500-HB manufactured by Exsia Co., Ltd. can be used. Moreover, in order to adjust the layer thickness of the protective layer 20 to be formed, it may be used after appropriately diluted with an organic solvent such as anhydrous dibutyl ether.

Here, polysilazane is a polymer in which Si—N (silicon-nitrogen) bonds are repeated in the molecule, and is not particularly limited as long as it can be easily converted to silica (SiO ₂ ). Can be used. In particular, perhydropolysilazane having a repeating structure of — (SiH ₂ —NH) — in which _two hydrogen atoms are bonded to Si atoms of Si—N bonds reacts with moisture in the atmosphere and is easily converted to silica. Therefore, it can be preferably used when forming the protective layer 20. A dense and amorphous high-purity silica (amorphous SiO ₂ ) layer can be obtained by using the organic solvent solution of perhydropolysilazane as a coating solution, drying in the air, and irradiating with UV.

In the above, the UV irradiation is performed in order to promote the reaction between polysilazane and moisture in the air to shorten the time required for conversion to silica and satisfy the productivity required for industrial production. In addition, by heating at the time of drying and at the time of UV irradiation, the reaction between polysilazane and atmospheric moisture can be promoted, and the time required for conversion to silica can be further shortened. Here, the drying is a process performed for the purpose of removing the solvent, preventing the flow of the coating film, and the like, and is generally performed in the range of 80 ° C to 130 ° C. In addition, as described above, drying is performed for the purpose of removing the solvent, preventing the flow of the coating film, and the like. Therefore, it is not necessary to perform drying for a long time, and it may be appropriately performed within a range of about 10 seconds to 5 minutes.

On the other hand, the purpose of UV irradiation is to promote the reaction between polysilazane and moisture in the atmosphere. By irradiating UV in a heated state, the reaction promoting effect by UV irradiation is enhanced. Specifically, it is preferable to heat in the range of 150 ° C to 350 ° C. When the temperature is lower than 150 ° C., the reaction promoting effect by heating cannot be sufficiently obtained, which is not preferable. Moreover, when it exceeds 350 degreeC, the heat load may be given with respect to the metal layer 10, and it is unpreferable. The time required for UV irradiation is the time required for polysilazane to be converted to silica after the polysilazane solution is coated and the polysilazane coating layer is cured. When UV irradiation is performed in the above temperature range, when the polysilazane coating layer, that is, the protective layer 20 having a layer thickness of 5 nm to 100 nm is formed, it is converted to silica in the range of 1 minute to 180 minutes. Therefore, when the UV irradiation time is less than 1 minute, the reaction between polysilazane and moisture may not be completed. If the polysilazane layer has the above thickness, it is converted into a silica layer within 180 minutes. There is little need to irradiate UV beyond minutes.

b) Chemical Vapor Phase Reaction Method (CVD Method) or Physical Vapor Deposition Method In forming the protective layer 20, in addition to the method of applying a polysilazane coating solution, a conventionally known chemical vapor reaction method or physical vapor deposition method is used. A SiO ₂ layer, a SiNx (silicon nitride) -SiO ₂ layer, or a SiNx layer may be formed. Thus, it is preferable to form an amorphous silica layer, a silicon nitride-silica layer, and a silicon nitride layer.

By forming the protective layer 20 made of the above silicon compound, the surface of the metal layer 10 is so-called glass coated, so that the oxidation effect of the metal layer 10 and the effect of preventing metal diffusion into the ceramic insulating layer 30 are achieved. In addition, when a sol-gel solution is applied to the surface of the metal layer 10 by a spin coating method or the like in the sol-gel method described below, the metal layer 10 is protected to prevent the metal layer 10 from being mechanically damaged. can do.

2-2) Ceramic Insulating Layer Forming Step Next, the ceramic insulating layer forming step will be described. The ceramic insulating layer forming step is characterized in that the ceramic insulating layer 30 is formed on the surface of the protective layer 20 laminated on the metal layer 10 in the protective layer forming step. By forming the ceramic insulating layer 30 on the surface of the protective layer 20, regardless of what method is adopted when forming the ceramic insulating layer 30, deterioration due to oxidation or the like of the metal layer 10 or the ceramic This is because diffusion of the base metal into the system insulating layer 30 can be prevented. As a method for forming the ceramic insulating layer 30, various methods such as a sol-gel method, an electrophoretic electrodeposition method, an MOCVD method, and a sputtering vapor deposition method can be employed. Here, a sol-gel method and an electrophoretic electrodeposition method, which are particularly advantageous when the ceramic insulating layer 30 is formed thin over a wide area, will be described.

a) Sol-Gel Method First, a method for forming the ceramic insulating layer 30 by the sol-gel method will be described. When the ceramic insulating layer 30 is formed by the sol-gel method, (a-1) a sol-gel solution preparation step for preparing a sol-gel solution, (a-2) the surface of the protective layer 20 of the metal layer 10 on the sol-gel solution It is preferable to pass through three steps: a coating step for applying to (a-3) and a firing step for forming the final ceramic insulating layer 30. Hereinafter, each step will be described.

(A-1) Sol-gel solution preparation step: The sol-gel solution preparation step is a step for preparing a sol-gel solution for forming the ceramic insulating layer 30 having a desired composition. The process is not particularly limited, and the sol-gel solution may be prepared by itself so as to be the ceramic insulating layer 30 having a desired composition, or a commercially available preparation solution may be used. . As a result, it is only necessary to prepare a sol-gel solution capable of forming the ceramic insulating layer 30 having a desired composition. For example, as the ceramic insulating layer 30, a BST layer having a perovskite structure as a crystal structure can be formed using 10 wt% BST (90/10/100) manufactured by Mitsubishi Materials. However, 90/10/100 is the molar ratio of barium, strontium, and titanic acid.

(A-2) Coating process: In the coating process, the sol-gel liquid prepared in the above-mentioned (A) sol-gel liquid preparation process is applied to the surface of the protective layer 20 of the metal layer 10, and the sol-gel liquid is dried to obtain the desired This is a step of obtaining a sol-gel solution coating layer having a layer thickness of. Here, when applying the sol-gel solution, a conventionally known method can be appropriately employed. However, in consideration of the uniformity of the layer thickness, the characteristics of the sol-gel solution, and the like, it is preferably performed by a spin coating method.

In the present invention, the coating method is characterized by adopting the following method. That is, applying a sol-gel solution to the surface of the protective layer 20 of the metal layer 10 and drying in an oxygen-containing atmosphere at a temperature range of 120 ° C. to 350 ° C. for 30 seconds to 10 minutes is repeated a plurality of times. It is preferable to adjust the layer thickness of the liquid coating layer. If the drying conditions are not met and the drying becomes insufficient, the final thickness of the ceramic insulating layer 30 may be reduced due to the flow of the coating film or re-dissolution during repeated application. Since it becomes uniform, it is not preferable. On the other hand, if the drying condition is out of the range and the drying becomes excessive, a heat load is applied to the metal layer 10 as a base material, and the metal layer 10 may be deteriorated. . In addition, as described above, by repeatedly applying and drying the sol-gel solution, it is easy to adjust the layer thickness of the sol-gel solution coating layer, and the ceramic insulating layer 30 having a desired thickness can be obtained. Can do.

(A-3) Firing step: The firing step is preferably performed at 400 to 800 ° C. for 5 to 120 minutes in an inert gas replacement (nitrogen gas atmosphere or the like; the same applies hereinafter) or a vacuum atmosphere. Through the firing step, the oxidation reaction of the precursor proceeds, and the ceramic insulating layer 30 according to the present invention can be obtained. The reason why the firing process is performed in an inert gas replacement or vacuum atmosphere is to prevent the metal layer 10 from being deteriorated. When the firing temperature is less than 400 ° C., the above oxidation reaction is incomplete, excellent adhesion to the metal layer 10 as a base material, ceramic as a dielectric layer having an appropriate fineness and a crystal structure of an appropriate particle size It is difficult to obtain the system insulating layer 30. On the other hand, when the firing temperature exceeds 800 ° C., firing is excessive, which is not preferable because the insulation of the ceramic insulating layer 30 is lowered, the physical strength of the metal layer 10 is lowered, and the conductivity is lowered. However, the firing temperature and firing time can be appropriately changed to an appropriate temperature and time depending on the type of constituent metal of the metal layer 10 and the composition of the sol-gel solution used for forming the ceramic insulating layer 30. Of course.

In the present invention, the ceramic insulating layer 30 is obtained by firing the sol-gel solution coating layer in the above-mentioned temperature range in the firing step. At this time, by using the protective layer 20 according to the present invention provided on the upper layer of the metal layer 10 as a base material, as described above, the deterioration of the metal layer 10, that is, the oxidation of the metal material constituting the metal layer 10 Can be prevented very effectively, and the deterioration of the metal layer 10 can be prevented. Further, even when a highly reactive BST layer is formed using a BST solution or the like as a sol-gel solution when the ceramic insulating layer 30 is formed, the metal layer 10 and the BST layer are formed in the firing step or the like. The reaction can be prevented and the metal constituting the metal layer 10 can be prevented from precipitating and diffusing in the ceramic insulating layer 30. Therefore, conventionally, when a temperature within the above range is applied to the metal layer 10 in the firing step, it has not been possible to positively adopt copper or a copper alloy in which an oxidation reaction easily proceeds. However, as described above, by providing the protective layer 20 on the upper layer of the metal layer 10, copper or a copper alloy can be suitably used as a constituent material of the metal layer 10.

b) Electrophoretic electrodeposition method Next, a method for forming the ceramic insulating layer 30 by the electrophoretic electrodeposition method will be described. When forming the ceramic insulating layer 30 by the electrophoretic electrodeposition method, (b-1) dielectric particles for obtaining the desired ceramic insulating layer 30 are dispersed in an organic solvent to obtain a dielectric particle dispersed slurry. A slurry preparation step, and (b-2) an electrodeposition step in which a cathode electrode and an anode electrode are placed in the dielectric particle-dispersed slurry and electrophoretic deposition is performed to form an electrodeposition layer on one of the electrodes. And (b-3) a firing step for firing the electrodeposition layer to form the final ceramic insulating layer 30.

First, the electrophoretic electrodeposition method will be briefly described. The surface of the dielectric particles in the dielectric particle dispersion slurry prepared in the (b-1) slurry preparation step is charged positively or negatively. In the (b-2) electrodeposition step, when a voltage is applied between the cathode electrode and the anode electrode arranged in the dielectric particle-dispersed slurry, the charged dielectric particles are electrophoresed. Adsorption and aggregation occur in the vicinity of one of the electrodes to form an electrodeposition layer made of dielectric particles on the electrode surface. The metal layer 10 according to the present invention is used as an electrode on the film formation side where the electrodeposition layer is formed. Then, the ceramic insulating layer 30 according to the present invention is obtained by firing the electrodeposition layer by the firing step (b-3). This electrophoretic electrodeposition method utilizes a so-called electrophoretic phenomenon, and has the advantages of high material use efficiency, high film formation speed, and excellent productivity. Therefore, when the ceramic insulating layer 30 is formed over a wide range on the surface of the metal layer 10 like the laminated body 100 of the ceramic insulating layer and the metal layer according to the present invention, the method can be suitably employed. it can. Hereinafter, each step will be further described.

(B-1) Slurry preparation step: The slurry preparation step is a step for obtaining a dielectric particle-dispersed slurry for forming the ceramic insulating layer 30 having a desired composition. In this step, a dielectric particle-dispersed slurry in which dielectric particles are dispersed in a polar organic solvent such as acetone is prepared.

As the dielectric particles, it is preferable to use perovskite type dielectric particles. The perovskite-type dielectric particles referred to here have a basic composition such as barium titanate, strontium titanate, barium strontium titanate, and bismuth zirconate. Among these, those having a basic composition of any one of barium titanate, strontium titanate, and barium strontium titanate are particularly preferable. This is because dielectric particles having these compositions have stable electrophoretic deposition properties. However, in this step, a commercially available dielectric particle dispersed slurry can also be used. In addition, manganese, silicon, nickel, aluminum, lanthanum, niobium, magnesium, tin, or the like may be added as appropriate. These additive components are segregated at the grain boundaries, thereby blocking the leakage current flow path and preventing the short circuit.

(B-2) Electrodeposition step: In the electrodeposition step, as described above, the metal layer 10 is used as an electrode on the electrodeposition layer forming side. As the counter electrode of the metal layer 10, it is preferable to use a material composed of any component of stainless steel, titanium, or an insoluble anode material. The metal layer 10 functions as a cathode electrode or an anode electrode in combination with the metal material constituting the metal layer 10 according to the present invention. The distance between these electrodes is preferably about 1 cm to 20 cm, and the voltage applied between the electrodes is preferably 0.5 V to 200 V.

If the distance between the electrodes is less than 1 cm, the inflow of the dielectric particle dispersed slurry is insufficient between the two electrodes, and stable electrophoretic deposition cannot be performed. On the other hand, when the distance between the electrodes exceeds 20 cm, the distance between the electrodes becomes too long, so that it is difficult to uniformly control the migration of the dielectric particles between the electrodes, and the layer thickness is uniform on the metal layer 10 side. It becomes difficult to form a simple electrodeposition layer.

When the distance between the electrodes is within the above range, the voltage applied between the electrodes is preferably 10V to 40V as described above. When the voltage applied between the two electrodes is less than 10 V, the migration speed of the dielectric particles is slow and the film formation speed is also lowered, so that the productivity required for industrial production is not satisfied. On the other hand, when the voltage applied between both electrodes exceeds 200 V, in the present invention, the metal layer 10 having the protective layer 20 laminated is used as the electrode on the film formation side, so that particles are deposited on the surface of the protective layer 20. If it does so, the said particle | grain will aggregate and it will become difficult to form an electrodeposition layer with uniform layer thickness. However, as the value of the voltage applied between the electrodes increases, the amount of dielectric particles deposited on the surface of the metal layer 10 as the electrode on the film forming side increases when the current is applied for the same time. Therefore, the ceramic insulating layer 30 having a desired thickness can be formed by controlling the value of the voltage applied between the two electrodes and the energization time.

(B-3) Firing step: In the electrophoretic electrodeposition method, the firing step can be performed basically under the same conditions as in the sol-gel method, and thus description thereof is omitted here.

As described above, a) the sol-gel method and b) electrophoretic electrodeposition method have been described as the ceramic insulating layer forming step. As described above, in the method for manufacturing the laminate 100 of the ceramic insulating layer and the metal layer according to the present invention. Various methods such as MOCVD and sputtering deposition can be employed. More preferably, after the ceramic insulating layer 30 is formed by these methods, a resin component impregnation step is provided. The impregnation step of the resin component is performed, for example, in (a) sol-gel method and (b) electrophoretic electrodeposition method after finishing the (a-3) and (b-3) firing steps, respectively.

Resin component impregnation step: The resin component impregnation step is a step for filling a structural defect serving as a leakage current flow path by impregnating a resin component between particles or grain boundaries present in the ceramic insulating layer 30. is there. As a resin component impregnated in the particles or grain boundaries present in the ceramic insulating layer 30, it is preferable to use a resin composition using an epoxy resin as a main component. In particular, the epoxy resin contains 40 wt% to 70 wt% of the epoxy resin, 20 wt% to 50 wt% of the polyvinyl acetal resin, and 0.1 wt% to 20 wt% of the melamine resin or urethane resin with respect to the total resin component. It is preferable to use a resin composition in which 5 wt% to 80 wt% of the resin is a rubber-modified epoxy resin.

However, any epoxy resin can be used without particular limitation as long as it is commercially available for molding laminated plates and electronic parts. Specifically, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, o-cresol novolac type epoxy resin, triglycidyl isocyanurate, N, N-diglycidylaniline and other glycidylamine compounds, Examples thereof include glycidyl ester compounds such as tetrahydrophthalic acid diglycidyl ester and brominated epoxy resins such as tetrabromobisphenol A diglycidyl ether. These epoxy resins are preferably used alone or in combination. Moreover, the polymerization degree and epoxy equivalent as an epoxy resin are not specifically limited.

Examples of epoxy resin curing agents include dicyandiamide, organic hydrazides, imidazoles, amines of aromatic amines, phenols such as bisphenol A and brominated bisphenol A, novolaks such as phenol novolac resins and cresol novolacs, An acid anhydride such as phthalic anhydride can be used. A hardening | curing agent may be used individually by 1 type, and 2 or more types may be mixed and used for it. The addition amount of the curing agent with respect to the epoxy resin can be appropriately determined according to each epoxy equivalent.

Furthermore, you may add a hardening accelerator with a hardening | curing agent as needed. In this case, as a curing accelerator, for example, a tertiary amine, an imidazole-based, a urea-based curing accelerator, or the like can be used.

In the resin composition used as the resin component impregnated in the ceramic insulating layer 30, the epoxy resin is preferably 40% by weight to 70% by weight of the total resin component as described above. When the compounding quantity of an epoxy resin is less than 40 weight%, the insulation and heat resistance of the ceramic type | system | group insulating layer 30 fall. On the other hand, when the compounding amount of the epoxy resin exceeds 70% by weight, when the resin component is cured, the so-called resin flow becomes too large, and the resin is uniformly distributed between particles in the ceramic insulating layer 30 or between grain boundaries. The resin component cannot be impregnated and the resin component tends to be unevenly distributed in the ceramic insulating layer 30, which is not preferable.

Moreover, it is preferable to use a rubber-modified epoxy resin as a part of the epoxy resin composition. As the rubber-modified epoxy resin, products marketed for adhesives or paints can be used without particular limitation. Specifically, “EPICLON® TSR-960” (trade name, manufactured by Dainippon Ink, Inc.), “EPOTOTOTO® YR-102” (trade name, manufactured by Toto Kasei), “Sumiepoxy® ESC-500” (trade name, Sumitomo Chemical) And "EPOMIK VSR 3531" (trade name, manufactured by Mitsui Petrochemical Co., Ltd.) can be used. These rubber-modified epoxy resins may be used alone or in combination of two or more. Here, the blending amount of the rubber-modified epoxy resin is preferably 5 to 80% by weight of the total amount of the epoxy resin. By using the rubber-modified epoxy resin, fixing of the resin component in the ceramic insulating layer 30 can be promoted. Therefore, when the amount of the rubber-modified epoxy resin is less than 5% by weight, the effect of promoting fixing in the ceramic insulating layer 30 cannot be obtained. On the other hand, if the blending amount of the rubber-modified epoxy resin exceeds 80% by weight, the heat resistance as a cured resin may be reduced.

Next, the polyvinyl acetal resin will be described. Here, the polyvinyl acetal resin is synthesized by a reaction between polyvinyl alcohol and aldehydes. In the present invention, as the polyvinyl acetal resin, those commercially available for paints and adhesives can be used without any particular limitation. In the present invention, the degree of polymerization of the raw material polyvinyl alcohol, the type of raw aldehydes and the degree of acetalization are not particularly limited, but the degree of polymerization is considered in consideration of heat resistance as a cured resin and solubility in a solvent. It is desirable to use products synthesized from 2000-3500 polyvinyl alcohol. Further, a modified polyvinyl acetal resin having a carboxyl group or the like introduced in the molecule is also commercially available, but can be used without particular limitation as long as there is no problem in compatibility with the combined epoxy resin. The blending amount of the polyvinyl acetal resin blended in the insulating layer is 20% by weight to 50% by weight of the total amount of the resin composition. If the blending amount is less than 20% by weight, the effect of improving the fluidity as a resin cannot be obtained. On the other hand, if the blending amount exceeds 50% by weight, the water absorption rate of the insulating layer after curing becomes high, which is extremely undesirable as a constituent material of the ceramic insulating layer 30.

The resin composition used in the present invention preferably contains a melamine resin or a urethane resin as a crosslinking agent for the polyvinyl acetal resin in addition to the above components.

As the melamine resin, an alkylated melamine resin commercially available for coating can be used. Examples of alkylated melamine resins include methylated melamine resins, n-butylated melamine resins, iso-butylated melamine resins, and mixed alkylated melamine resins. The molecular weight and alkylation degree as a melamine resin are not particularly limited.

As the urethane resin, a resin containing an isocyanate group in a molecule marketed for an adhesive or a paint can be used. Examples of the urethane resin include a reaction product of a polyisocyanate compound such as tolylene diisocyanate, diphenylmethane diisocyanate, and polymethylene polyphenyl polyisocyanate and a polyol such as trimethylolpropane, polyether polyol, and polyester polyol. Since these compounds are highly reactive as resins and may be polymerized by moisture in the atmosphere, in the present invention, these resins are blocked with phenols or oximes so as not to cause this problem. It is preferable to use a urethane resin called isocyanate.

The blending amount of the melamine resin or the urethane resin added to the resin composition in the present invention is 0.1% by weight to 20% by weight of the total amount of the resin composition. When the blending amount is less than 0.1% by weight, the crosslinking effect of the polyvinyl acetal resin is insufficient, the heat resistance of the insulating layer is lowered, and when the blending amount exceeds 20% by weight, the fixability in the ceramic insulating layer 30 is achieved. Deteriorates.

In addition to the above essential components, additives such as inorganic fillers, antifoaming agents, leveling agents, coupling agents and the like can be used for this resin composition as desired. These improve the permeability of the resin component to the ceramic insulating layer 30 and are effective in improving flame retardancy and reducing costs.

The above resin composition is present in the ceramic insulating layer 30 by applying it to the surface of the ceramic insulating layer 30 by a spin coating method or the like after the firing step and heating it using a hot plate, an oven or the like. The resin component can be impregnated between particles or between grain boundaries.

Upper electrode layer forming step: As described above, when the multilayer body 100 according to the present invention is used as a capacitor circuit forming material (110 (see FIG. 1)), an upper electrode made of a metal material is formed on the upper surface of the ceramic insulating layer 30. An upper electrode layer forming step for forming the layer 40 may be provided. In this case, the upper electrode formation layer 40 may be formed by bonding a metal foil of any one of copper foil, copper alloy foil, nickel foil and nickel alloy foil to the upper surface of the ceramic insulating layer 30, The upper electrode forming layer 40 may be formed by a plating method using any one of copper, a copper alloy, nickel, a nickel alloy, and aluminum, or a method such as sputtering deposition.

Next, the present invention will be specifically described with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

Example 1 describes an example in which a laminated body 100 of a ceramic insulating layer and a metal layer according to the present invention is manufactured by using a sol-gel method when the ceramic insulating layer 30 is formed.

<Manufacture of Laminated Body 100 of Ceramic Insulating Layer and Metal Layer>
i) Protective layer forming step Here, a smooth surface copper foil (NA-DFF, 18 μm) having a laminated surface of Rz ≦ 1.0 μm and having a thickness of 18 μm manufactured by Mitsui Mining & Smelting Co., Ltd. was used as the metal layer 10. Then, polysilazane solution diluted with polysilazane silica coating agent (SSL-SD500-HB) anhydrous dibutyl ether manufactured by Exsia Co., Ltd. It was applied to the surface of the layer 10 by a spin coating method, dried in the air using a hot plate at 150 ° C. for 1 minute, and then irradiated with UV while being heated in the air using a hot plate at 220 ° C. for 30 minutes. . Thereby, a SiO ₂ layer having a layer thickness of 20 nm was formed. By the above process, the metal layer 10 obtained by laminating a 20 nm SiO ₂ layer as the protective layer 20 on the surface of the 18 μm smooth copper foil as the metal layer 10 was obtained. However, SEM (manufactured by JEOL; JSM-700IF) (magnification 100,000 times) was used to measure the thickness of the protective layer 20.

ii) Formation of Ceramic Insulating Layer 30 Next, the following (a-1) sol-gel liquid preparation step, (a-2) coating step, (a-3) are applied to the surface of the metal layer 10 by a sol-gel method. The ceramic insulating layer 30 was formed through the four steps of the firing step and (a-4) resin impregnation step.

(A-1) Sol-gel solution preparation step: In the sol-gel solution preparation step, a commercially available sol-gel solution (10 wt% BST (90/10/100) solution manufactured by Mitsubishi Materials Corporation) was used.

(A-2) Coating process: In the coating process, the above sol-gel solution is applied to the surface of the protective layer 20 of the metal layer 10 by a spin coating method, and then air is applied at 190 ° C. for 1 minute using a hot plate. Dried in. With this step as one unit step, the one unit step was repeated 6 times to form a sol-gel liquid coating layer.

(A-3) Firing step: Then, the metal layer 10 provided with the sol-gel liquid coating layer is subjected to a nitrogen atmosphere (atmosphere in which saturated water vapor containing 25 ° C. is blown; the same applies to the firing step hereinafter). Using a tube furnace, firing was performed under firing conditions of 600 ° C. × 60 minutes.

(A-4) Resin impregnation step: Thereafter, 100 parts by weight of an epoxy resin (Epicoat 828 manufactured by Japan Epoxy Resin Co., Ltd.) and 1 part by weight of an imidazole compound (Curesol 2E4MZ manufactured by Shikoku Kasei Kogyo Co., Ltd.) as an epoxy resin curing agent As a resin composition, methyl ethyl ketone (reagent) was used as a solvent to prepare an epoxy resin varnish having a total amount of epoxy resin and an epoxy resin curing agent of 0.22 wt% as a solid content. Then, by applying the epoxy resin varnish as a coating solution by spin coating, it is applied to the surface of the sol-gel solution coating layer after baking, and heated in the atmosphere at 190 ° C. for 90 minutes using a hot plate, and the resin is ceramic. Impregnation was carried out between particles or grain boundaries existing in the system insulating layer 30. Thus, a laminate 100 of the ceramic insulating layer and the metal layer of Example 1 according to the present invention was manufactured.

As the laminated body 100 of the ceramic insulating layer and the metal layer of Example 2, it was carried out except that (a-3) the firing step was performed at 500 ° C. in the ii) ceramic insulating layer forming step of Example 1 above. A laminate 100 of a ceramic insulating layer and a metal layer of Example 2 according to the present invention was manufactured by the same method as Example 1.

Next, the ceramic insulating layer 30 was formed by electrophoretic deposition as the laminate 100 of the ceramic insulating layer and the metal layer of Example 3.

i) Protective layer forming step: In the protective layer forming step, as in Example 1 and Example 2 above, surface smooth copper having a laminated surface of Rz ≦ 1.0 μm and a layer thickness of 18 μm manufactured by Mitsui Mining & Smelting Co., Ltd. A foil (NA-DFF, 18 μm) was used as the metal layer 10. Then, using a polysilazane silica coating agent (SSL-SD500-HB) manufactured by Exsia Co., Ltd. without dilution, it was dried in the atmosphere at 150 ° C. for 1 minute using a hot plate, and then in the atmosphere at 250 ° C. × 90 A protective layer 20 having a thickness of about 60 nm was formed on the upper surface of the metal layer 10 in the same manner as in Example 1 and Example 2 except that UV irradiation was performed while heating using a hot plate. The thickness of the protective layer 20 was measured using SEM (manufactured by JEOL; JSM-700IF) (magnification 100,000 times) in the same manner as in Example 1 and Example 2.

ii) Ceramic insulating layer forming step: In the ceramic insulating layer forming step, the ceramic insulating layer 30 was formed on the surface of the protective layer 20 of the metal layer 10 by electrophoretic deposition.

(B-1) Slurry preparation step: In Example 3, a suspension in which dielectric particles having an average particle diameter of 80 nm are dispersed in n-butanol is mixed with acetone as an organic solvent, so that the dielectric particle concentration is Dielectric particle-dispersed slurry was obtained by ultrasonic vibration stirring for 5 minutes so as to be 10 g / l. However, in the above, the average particle diameter of dielectric particles refers to the arithmetic average value when the major axis of 100 particles is laterally extended using the SEM.

(B-2) Electrodeposition step: In the electrodeposition step, the metal layer 10 is used as a cathode electrode, a stainless steel plate is used as an anode electrode, and the two electrodes are separated from each other by 20 mm in the dielectric particle dispersion slurry prepared above. Arranged. Then, a BST electrodeposition layer having a thickness of about 1.5 μm was formed on the metal layer 10 as a cathode electrode by applying a voltage of 30 V between both electrodes and applying a direct current for 20 seconds.

(B-3) Firing step: The metal layer 10 on which the BST electrodeposition layer was formed was fired using a tube furnace at 600 ° C. for 60 minutes in a nitrogen atmosphere.

(B-4) Resin impregnation step: Next, the resin component is impregnated between particles or grain boundaries existing in the BST electrodeposition layer after firing by the same method as in Example 1 and Example 2, A ceramic insulating layer 30 according to the invention was formed, and a laminate 100 of the ceramic insulating layer 30 and the metal layer 10 of Example 3 according to the present invention was manufactured.

Comparative example

[Comparative Example 1]
In order to compare with the laminate 100 of the ceramic insulating layer and the metal layer of Example 1, i) Sol-gel method as in Example 1 except that the protective layer 20 was not provided in the protective layer forming step. Thus, the ceramic insulating layer 30 was formed to obtain a laminate of the ceramic insulating layer and the metal layer of Comparative Example 1.

[Comparative Example 2]
In order to compare with the laminated body 100 of the ceramic type insulating layer and metal layer of Example 2, i) Sol-gel method as in Example 2 except that the protective layer 20 was not provided in the protective layer forming step. Thus, a ceramic insulating layer 30 was formed to obtain a laminate of the ceramic insulating layer and the metal layer of Comparative Example 2.

[Comparative Example 3]
In order to compare with the laminate 100 obtained in Example 3, i) a ceramic insulating layer formed by electrophoretic deposition in the same manner as in Example 3 except that the protective layer 20 was not provided in the protective layer forming step. 30 to form a laminate of the ceramic insulating layer and the metal layer of Comparative Example 3. However, in Comparative Example 3, since the protective layer 20 made of SiO ₂ which is an insulating material is not provided on the surface of the metal layer 10, the ceramic insulating layer having substantially the same thickness as the ceramic insulating layer 30 of Example 3. In order to form 30, the voltage applied between both electrodes is set to 20 V in the electrodeposition process.

[Evaluation]
(I) Sol-Gel Method First, the present invention is compared with the laminate 100 of Example 1 and Example 2 in which the ceramic insulating layer 30 is formed by the sol-gel method and the laminate of Comparative Example 1 and Comparative Example 2. The laminate 100 of the ceramic insulating layer and the metal layer is evaluated.

Copper diffusion to ceramic insulating layer 30 (1): FIG. 2A is a SEM photograph showing the surface of the ceramic insulating layer 30 formed in Example 1, and FIG. 4 is a SEM photograph showing the surface of the formed ceramic insulating layer 30. 2C is an SEM photograph showing the surface of the ceramic insulating layer 30 formed in Comparative Example 1, and FIG. 2D shows the surface of the ceramic insulating layer 30 formed in Comparative Example 2. It is a SEM photograph. However, each SEM photograph was obtained by photographing the surface of the ceramic insulating layer 30 at a magnification of 30,000 using a SEM (JSM-700IF) manufactured by JEOL.

Here, in Example 1 and Comparative Example 1, the firing temperature when forming the ceramic insulating layer 30 was 600 ° C. On the other hand, in Example 2 and Comparative Example 2, the firing temperature was 500 ° C. First, referring to FIG. 2C, copper crystals can be observed on the surface of the ceramic insulating layer 30 of Comparative Example 1 fired at 600 ° C. On the other hand, referring to FIG. 2D, no copper crystals are observed on the surface of the ceramic insulating layer 30 of Comparative Example 2 fired at 500.degree. However, in FIG. 2 (d), as indicated by an arrow A, portions that are visually recognized as white on the surface of the ceramic insulating layer 30 are observed. The part visually recognized as white is a part swollen by firing (see FIG. 3C). As described above, when copper is employed as the metal layer 10, if the firing temperature at the time of forming the ceramic insulating layer 30 is increased, copper diffuses throughout the ceramic insulating layer 30, thereby insulating the ceramic insulating layer 30. There is a risk of causing a decrease in performance, occurrence of a short circuit, an increase in leakage current, and the like. On the other hand, when the firing temperature is 500 ° C., copper diffusion in the ceramic insulating layer 30 is not observed as compared with when the firing temperature is 600 ° C., but swelling of the ceramic insulating layer 30 is observed.

In contrast to the above Comparative Example 1 and Comparative Example 2, in Example 1 and Example 2 according to the present invention, the protective layer 20 made of SiO ₂ is formed on the surface of the copper foil as the metal layer 10 and then the ceramic. The laminated body 100 (refer FIG. 1) in which the system insulation layer 30 was formed is obtained. In Example 1, a laminated body of the metal layer 10 and the ceramic insulating layer 30 was formed in the same manner as in Comparative Example 1 except that the protective layer 20 was provided. See FIG. 2A. Then, it can be seen that copper crystals are not recognized and copper diffusion into the ceramic insulating layer 30 is prevented. Further, in FIGS. 2A and 2B, since there is no portion that is visually recognized as white on the surface of the ceramic insulating layer 30, it can be seen that the swelling of the ceramic insulating layer 30 does not occur. From the above, the protective layer 20 is formed on the metal layer 10, and the ceramic insulating layer 30 is formed on the surface of the protective layer 20, thereby diffusing the constituent metals of the metal layer 10 into the ceramic insulating layer 30. It was confirmed that there was an effect to suppress, a change in shape due to oxidation of the metal layer 10 was prevented, and a smooth ceramic insulating layer 30 could be formed.

Next, FIGS. 3A and 3B show SEM photographs in which a cross section of the laminate 100 (see FIG. 1) of the metal layer 10 and the ceramic insulating layer 30 formed in Example 1 is shown. 3C and 3D show SEM photographs in which a cross section of the laminate 100 of the metal layer 10 and the ceramic insulating layer 30 formed in Comparative Example 1 is photographed. 3 (a) and 3 (c) are taken at a magnification of 5,000 times, and FIGS. 3 (b) and 3 (d) are taken at a magnification of 50,000 times.

As shown in FIGS. 3A and 3B, the laminate 100 formed in Example 1 was formed in a thin film between the copper foil as the metal layer 10 and the ceramic insulating layer 30. A protective layer 20 is observed. And the surface of the ceramic type | system | group insulating layer 30 is smooth, and a copper crystal | crystallization and the swelling of a surface are not recognized. On the other hand, referring to FIGS. 3C and 3D, in the laminate formed in Comparative Example 1, countless copper crystals diffused on the surface of the ceramic insulating layer 30 are recognized.

Copper diffusion to ceramic insulating layer 30 (2): Next, FIGS. 4A and 4B show cross-sectional SEM photographs of the laminate 100 formed in Example 2. FIG. Moreover, the cross-sectional SEM photograph of the said laminated body formed in FIG.4 (c), (d) in the comparative example 2 is shown. 4A and 4C are taken at a magnification of 5,000 times, and FIGS. 4B and 4D are taken at a magnification of 50,000 times.

Referring to FIG. 4, in Example 2 and Comparative Example 2, since the firing temperature is 500 ° C., no copper crystal diffused on the surface of the ceramic insulating layer 30 is observed. However, as shown in FIGS. 4C and 4D, in the laminated body of Comparative Example 2, innumerable swelling was observed on the surface of the ceramic insulating layer 30, and the surface of the ceramic insulating layer 30 was wavy. I understand that As described above, when unevenness is generated on the surface of the ceramic insulating layer 30 due to the shape change accompanying the oxidation of the metal layer 10, the insulating characteristic or the dielectric characteristic becomes uneven depending on the location, and the lamination of the ceramic insulating layer and the metal layer is performed. The yield as a body cannot be improved. On the other hand, as for the laminated body 100 of Example 2, as shown in FIG.4 (b), the protective layer 20 formed in the thin film shape between the copper foil layer which is the metal layer 10, and the ceramic type | system | group insulating layer 30 is shown. Is recognized. Further, it can be seen that no swelling of the surface of the ceramic insulating layer 30 formed on the surface of the protective layer 20 is observed, and the ceramic insulating layer 30 having a uniform layer thickness is obtained.

From the above cross-sectional SEM photograph, in the present invention, the ceramic insulating layer 30 having a uniform layer thickness can be formed on the upper surface of the metal layer 10 via the protective layer 20, and copper diffusion to the ceramic insulating layer 30 can be prevented. It was confirmed that this could be prevented. Therefore, according to the present invention, it is possible to prevent deterioration of the insulating property and dielectric property of the ceramic insulating layer 30 due to metal diffusion, and to manufacture the laminate 100 of the ceramic insulating layer and the metal layer with high production yield. it can.

Oxidation of metal layer (1): Next, in order to evaluate the oxidation state of copper as the metal layer 10, the ceramic system formed in Example 1 and Example 2 using X'Pert PRO manufactured by Panalical Co., Ltd. X-ray diffraction of the surface of the insulating layer 30 was performed. FIG. 5 shows the result. In FIG. 5, the horizontal axis indicates the incident angle (2θ), and the vertical axis indicates the intensity (au). FIG. 6 shows the X-ray diffraction results of the ceramic insulating layer 30 formed in Comparative Example 1 and Comparative Example 2.

First, Comparative Example 1 and Comparative Example 2 are examined. FIG. 6 shows the ceramic insulation formed under the same conditions as in Comparative Example 1 and Comparative Example 2 together with the X-ray diffraction results of each ceramic insulating layer 30 in (a) Comparative Example 1 and (b) Comparative Example 2. The X-ray diffraction result (c) before firing of the layer 30 is also shown. For each of Comparative Examples 1 and 2, as shown in FIG. 6 (a), (b) , diffraction peaks indicating the BaTiO ₃ is confirmed by performing firing. From this, it can be seen that the oxidation reaction of the BaTiO ₃ precursor progressed by firing, and the ceramic insulating layer 30 was formed. On the other hand, since the diffraction peak indicating Cu 2 _O by performing firing appears, copper constituting the metal layer 10 by firing is observed to have oxidized.

Next, with reference to FIG. 5, Example 1 and Example 2 are examined. FIG. 5 shows (a) the firing of the ceramic insulating layer 30 formed under the same conditions as in the first and second embodiments, together with the X-ray diffraction results of the respective ceramic insulating layers 30 in the first and second embodiments. The previous X-ray diffraction result (c) is also shown. Referring to FIGS. 5A and 5B, for the ceramic insulating layer 30 formed in Example 1 and Example 2, although a diffraction peak indicating BaTiO ₃ appears, a diffraction peak indicating Cu ₂ O appears. Has not appeared. Therefore, from the result, by forming the protective layer 20 on the metal layer 10, it is possible to effectively prevent oxidation of the copper constituting the metal layer 10 in the firing step when forming the ceramic insulating layer 30. It was confirmed that it was possible.

Oxidation of metal layer (2): Next, FIG. 7 and FIG. 8 are electron beam microanalyzer photographs in the cross section of the laminate of the metal layer 10 and the ceramic insulating layer 30 formed in Example 1 and Comparative Example 1, respectively. Show. However, for taking the sectional analysis photograph, an energy dispersive X-ray analyzer INCA Energy PentaFETx3. It was performed using.

Here, referring to FIG. 8, in the laminated body formed in Comparative Example 1, first, as shown in FIG. 8A, a state in which copper is diffused on the surface of the ceramic insulating layer 30 is observed. The This is also apparent from the dispersed state of copper atoms (Cu) shown in FIG. On the other hand, as shown in FIG. 8C, the presence of oxygen atoms (O) is confirmed inside the metal layer 10, and it can be seen that copper constituting the metal layer 10 is oxidized.

On the other hand, referring to FIG. 7, no diffusion of copper on the surface of the ceramic insulating layer 30 is observed in FIG. Further, referring to FIG. 7C, the distribution of oxygen atoms remains only in the ceramic insulating layer 30, and the oxidation reaction of the precursor of BiTO ₃ proceeds by firing, but the oxidation reaction of copper does not occur. This is also confirmed from this figure. Further, as shown in FIG. 7E, the distribution of silicon atoms (Si) is recognized between the metal layer 10 and the ceramic insulating layer 30, and the protective layer 20 made of SiO ₂ is formed in a thin film shape. Can be confirmed.

Next, Table 1 shows the results of evaluating the capacity density, dielectric loss tangent, and production yield in the laminate 100 of the ceramic insulating layer and the metal layer formed in Example 1 and Example 2. However, in each example and each comparative example, the evaluation was performed for the case where resin impregnation was performed on the ceramic insulating layer 30 and the case where it was not performed. Table 1 shows both of these evaluation results. ing. In the above evaluation, the capacitance density and dielectric loss tangent were measured using an LCR high tester 3532-50 manufactured by HIOKI. Furthermore, with respect to production yield, 16 laminated bodies 100 of ceramic insulating layers and metal layers are manufactured for each condition, and the quality of each laminated body 100 of ceramic insulating layers and metal layers is set to capacity density and dielectric. Each item of tangent and leakage current was evaluated and evaluated based on the proportion of non-defective products.

Referring to Table 1, first, in Examples 1 and 2, when resin impregnation is not performed between particles or grain boundaries in the ceramic insulating layer 30, Comparative Examples 1 and 2 in terms of capacity density. Smaller than. However, the high capacity density of the laminate of the ceramic insulating layer and the metal layer obtained in Comparative Example 1 and Comparative Example 2 is considered to be caused by an increase in leakage current due to a short circuit. As a result, in Comparative Example 1 and Comparative Example 2, the production yields were as low as 18.8% and 68.8%, respectively, and it was difficult to obtain good products with good yields. On the other hand, in Example 1 and Example 2, as described above, the diffusion of copper in the ceramic insulating layer 30 is prevented, and the layer thickness of the ceramic insulating layer 30 is also configured uniformly. As a result, the occurrence of short circuits is small and the value of leakage current is small. In addition, Example 1 and Example 2 have lower dielectric loss tangent values than Comparative Example 1 and Comparative Example 2, respectively. As a result, the production yield was 81.3% in Example 1 and 100% in Example 2.

Further, when the resin impregnation is performed between the particles in the ceramic insulating layer 30 or between the grain boundaries in the first and second embodiments, the capacity density is reduced as compared with the case where the resin impregnation is not performed. The tangent value was 1/10 or less, and it was confirmed that a good product having a small dielectric tangent value can be obtained. Further, the resin impregnation can fill the structural defect of the ceramic insulating layer 30 serving as a flow path for the leakage current, so that a short circuit can be prevented and the leakage current can be further reduced. As a result, the production yield was 81.3% when the resin impregnation was not performed, but it could be improved to 93.8% by performing the resin impregnation. On the other hand, even when the resin impregnation is performed, the laminate of the ceramic insulating layer and the metal layer obtained in Comparative Example 1 and Comparative Example 2 is short-circuited, the production yield is 0%, and the capacity Density and dielectric loss tangent could not be measured.

Next, the leakage current density is evaluated with reference to FIG. 9 and FIG. In the evaluation, first, in the laminated body 100 of the ceramic insulating layer and the metal layer obtained in Example 1 and Comparative Example 1, a copper layer (upper part) was formed on the surface of the ceramic insulating layer of each laminated body by a sputtering vapor deposition method. Electrode forming layer) was formed. Then, using this copper layer as the upper electrode and the metal layer 10 as the lower electrode, a voltage was applied between these two electrodes, and the leakage current density with respect to the voltage value was measured. At this time, for Example 1 and Example 2, the leakage current density in the presence or absence of resin impregnation of the ceramic insulating layer 30 was also evaluated. FIG. 9A shows the measurement result for Example 1 when the resin impregnation of the ceramic resin layer 30 is performed, and FIG. 9B shows the measurement result for Example 1 when the resin impregnation is not performed. (C) has shown the measurement result about the comparative example 1. FIG. Similarly, FIG. 10A shows the measurement result for Example 2 when the resin impregnation of the ceramic resin layer 30 is performed, and FIG. 10B shows the measurement result for Example 2 when the resin impregnation is not performed. The measurement results are shown, and (c) shows the measurement results for Comparative Example 2.

First, Example 1 and Comparative Example 1 are evaluated. Referring to FIG. 9, the ceramic insulation of Example 1 according to the present invention shown in (a) and (b) of the laminate of the ceramic insulation layer and metal layer of Comparative Example 1 shown in (c). It can be seen that the laminate 100 of the layer and the metal layer has a leakage current density value reduced to 1/1000 or less. Further, FIG. 9 shows that when the resin-impregnated ceramic insulating layer 30 in Example 1 (a) is compared with the resin-impregnated (b) (b), the resin-impregnated one leaks. It can be seen that the current density is low.

Next, Example 2 and Comparative Example 2 are evaluated. Regarding Example 2 and Comparative Example 2, the same tendency as in Example 1 and Comparative Example 1 was observed. That is, referring to FIG. 10, the ceramic of Example 2 according to the present invention shown in (a) and (b) of the laminate of the ceramic insulating layer and metal layer of Comparative Example 2 shown in (c). It can be seen that the laminate 100 of the system insulating layer 30 and the metal layer 10 has a leakage current density value reduced to 1/1000 or less. From FIG. 10, in Example 2, when the resin-impregnated ceramic insulating layer 30 (a) and the resin-impregnated (b) were compared, the ceramic insulating layer 30 was compared. It can be seen that the value of the leakage current density is lower when the resin is impregnated.

2. Electrophoretic electrodeposition method Next, the laminate 100 of the ceramic insulating layer and the metal layer of Example 3 in which the ceramic insulating layer 30 was formed by the electrophoretic electrodeposition method, and the ceramic insulating layer and the metal layer of the comparative example The laminate 100 of the ceramic insulating layer and the metal layer according to the present invention is evaluated while comparing with the laminate.

i) Cross-sectional evaluation Using a scanning electron microscope (JSM-700IF) manufactured by JEOL, the metal layer 10 and the ceramic insulating layer 30 in the laminate 100 of the ceramic insulating layer and the metal layer obtained in Example 3 were used. About the laminated body 100 and the laminated body of the metal-based layer 10 and the ceramic-based insulating layer 30 in the laminated body of the ceramic-based insulating layer and the metal layer obtained in Comparative Example 3, respectively, a cross-section is photographed, and the state of copper oxidation analyzed.

11A is a SEM photograph showing a cross section of the laminate 100 formed in Example 3, and FIG. 11B is a SEM photograph showing a cross section of the laminate formed in Comparative Example 3. FIG. Referring to FIG. 11A, in the laminate 100 of Example 3, the protective layer 20 made of thin SiO ₂ between the copper foil as the metal layer 10 and the ceramic insulating layer 30 can be confirmed. . On the other hand, referring to FIG. 11B, it can be seen that a copper oxide layer formed by oxidizing copper is formed between the copper foil layer and the ceramic insulating layer 30 instead of the protective layer 20. Thus, by providing the protective layer 20 made of a silicon compound on the surface of the metal layer 10, it is possible to prevent oxidation of the metal constituting the metal layer 10, that is, copper, and to prevent deterioration of the metal layer 10. Can do.

ii) Leakage Current Density Next, the leakage current density of the laminate 100 of the ceramic insulating layer and the metal layer obtained in Example 3 and Comparative Example 3 was evaluated. In the evaluation, the leakage current density when a voltage was applied between the two electrodes was measured using the metal layer 10 as the lower electrode and the copper layer formed on the ceramic insulating layer as the upper electrode. The measurement of the leakage current density was performed using R8252 DIGITAL ELECTROMETER manufactured by ADVANTEST. The results are shown in FIG. However, in FIG. 12, (a) is a measurement result about Example 3, (b) is a measurement result about Comparative Example 3. Further, (c) will be described later.

As shown in FIG. 12, the laminate 100 (a) of the ceramic insulating layer and the metal layer of Example 3 according to the present invention is the laminate (b) of the ceramic insulating layer and the metal layer of Comparative Example 3. It can be seen that the value of the leakage current density is small as compared with the above, and a short circuit between the upper electrode and the lower electrode is prevented. Moreover, when the voltage applied between both electrodes is 20 V or more, the value of the leakage current density in the laminate 100 of the ceramic insulating layer and the metal layer of Example 3 is the same as that of the ceramic insulating layer of Comparative Example 3. Although it is about 1/10 of the value of the leakage current density in the laminate with the metal layer, the difference increases when the voltage applied between the two electrodes is less than 20V. For example, when the voltage applied between the two electrodes is in the range of 6V to 10B, it becomes 1/100 or less. Therefore, the ceramic insulating layer as the insulating layer or the dielectric layer in the laminated body 100 of the ceramic insulating layer and the metal layer according to the present invention has high reliability, and operates at a lower voltage using the laminated body 100. It can be said that the effect of reducing leakage current is great when forming an electronic circuit (including a semiconductor circuit).

Table 2 shows the evaluation results of the capacity density, dielectric loss tangent, production yield, and layer thickness of the ceramic insulating layer in the laminate 100 of the ceramic insulating layer and the metal layer obtained in Example 3 and Comparative Example 3. Show.

As shown in Table 2, in Example 3, a voltage of 30 V was applied for 20 seconds in the electrodeposition process, and in Comparative Example 3, a voltage of 20 V was applied for 20 seconds in the electrodeposition process. However, the finally obtained ceramic insulating layers 30 had substantially the same thickness, which were 1.6 μm and 1.5 μm, respectively. This is because the protective layer 20 made of SiO ₂ which is an insulating material is provided on the surface of the metal layer 10 formed in Example 3, so that the protective layer 20 is not provided with the metal layer 10 of the comparative example. In comparison, it is conceivable that the electrical characteristics during electrodeposition are degraded. However, as shown in FIG. 13 for reference, even when the protective layer 20 made of SiO ₂ is provided on the surface of the metal layer 10 (copper foil), if the value of the voltage applied during electrodeposition is increased, the film forming side The amount of particles deposited on the electrode surface increases. Therefore, the ceramic insulating layer 30 having a desired layer thickness is formed through the protective layer 20 by changing the voltage, energizing time, etc. as appropriate, and adjusting the amount of deposited particles deposited on the electrode surface on the film formation side. 10 upper layers can be laminated.

On the other hand, the capacity density of the laminate 100 of the ceramic insulating layer and the metal layer of Example 3 is lower than that of the laminate of the ceramic insulating layer and the metal layer of Comparative Example 3. However, it is possible to improve the capacity density by reducing the thickness of the ceramic insulating layer 30. In addition, the dielectric loss tangent value of the laminated body 100 of the ceramic insulating layer and the metal layer of Example 3 is lower than the laminated body of the ceramic insulating layer and the metal layer of Comparative Example 3, and the production yield is also implemented. Example 3 is higher. When the thickness of the ceramic insulating layer 30 is increased by about 1.5 times, even if the protective layer 20 is not provided, the insulating property of the ceramic insulating layer 30 is improved and the capacity density is reduced, but the leakage current density is also reduced. . However, no improvement in the value of dielectric loss tangent is observed.

Here, the reference shown in Table 3 is the ceramic insulating layer when the electrodeposition process is performed at 30 V when the laminate of the ceramic insulating layer and the metal layer of Comparative Example 3 is manufactured. It is an evaluation result about a laminated body with a metal layer. As shown for reference, the thickness of the ceramic insulating layer 30 was increased about 1.5 times by performing the electrodeposition step at 30V. FIG. 12C shows the measurement result of the leakage current density for the laminate shown as this reference example. 12A and 12C are compared, the value of the leakage current density is obtained by increasing the layer thickness of the ceramic insulating layer 30 in Comparative Example 3 by about 1.5 times. A value similar to 3 is shown. In other words, the laminated body 100 according to the present invention can effectively prevent the occurrence of a leakage current as compared with the conventional case even when the ceramic insulating layer 30 is thinned, and the reliability. It is possible to form an electronic circuit or electronic component circuit having a high height.

Although not shown, the protective layer 20 was formed so that the thickness of the protective layer 20 was 20 nm when the laminate 100 of the ceramic insulating layer and the metal layer of Example 3 was formed. . As a result, even when the thickness of the protective layer 20 is reduced, the leakage current density can be reduced as compared with the case where the protective layer 20 is not provided, and various values such as a decrease in the dielectric loss tangent value can be obtained. The effect of was recognized.

As described above, even when a copper foil is used as the metal layer 10 of the metal layer 10, even when a high temperature is applied in the firing process when the ceramic insulating layer 30 is formed, the metal layer 10 Oxidation can be prevented very effectively, and a decrease in the conductivity of the metal layer 10 can be prevented. At the same time, by providing the protective layer 20 on the metal layer 10, the metal constituting the metal layer 10 is prevented from diffusing into the ceramic insulating layer 30, and the insulating property of the ceramic insulating layer 30 is lowered. Alternatively, it is possible to prevent a decrease in dielectric characteristics. Therefore, by using the laminate 100 of the ceramic insulating layer and the metal layer according to the present invention, it becomes possible to form an electronic circuit or electronic component having higher reliability than the conventional one, and the ceramic system. The production yield of the laminated body 100 of an insulating layer and a metal layer can be improved.

The laminate of the ceramic insulating layer and the metal layer according to the present invention can be used very effectively as a forming material for reducing the leakage current of the insulating layer and forming a highly reliable electronic circuit or electronic component. . Furthermore, by laminating the protective layer on the surface of the copper foil layer, oxidation or the like of the copper foil layer under a high temperature process can be prevented. For this reason, since there is a high temperature process in the past, there is an excellent effect that it is possible to employ copper foil as various constituent materials even when copper foil cannot be employed. Can expand the industrial applicability of copper foil.

DESCRIPTION OF SYMBOLS 10 ... Metal layer 20 ... Protective layer 30 ... Ceramic type insulating layer 40 ... Upper electrode formation layer 100 .. Laminated body of ceramic type insulating layer and metal layer

Claims

A laminate of a ceramic insulating layer and a metal layer,
The metal layer is provided with a protective layer made of a silicon compound having a thickness of 5 nm to 100 nm on the surface on which the ceramic insulating layer is provided,
A laminate of a ceramic insulating layer and a metal layer.
The laminate of a ceramic insulating layer and a metal layer according to claim 1, wherein the protective layer is made of an amorphous silicon compound.
2. The laminate of a ceramic insulating layer and a metal layer according to claim 1, wherein the silicon compound is one selected from SiO 2 , SiN x —SiO 2 (x> 0), and SiN x (x> 0). .
The laminate of a ceramic insulating layer and a metal layer according to claim 1, wherein the protective layer is formed by any one of a chemical solution coating method, a chemical vapor reaction method, and a physical vapor deposition method.
The laminate of a ceramic insulating layer and a metal layer according to claim 1, wherein the metal layer is made of any one selected from copper, copper alloy, aluminum, aluminum alloy, nickel and nickel alloy.
Between the metal layer and the protective layer, at least one kind of surface treatment layer selected from nickel, nickel alloy, zinc, zinc alloy, chromium and chromium alloy and / or a silane coupling agent layer is provided. A laminate of a ceramic insulating layer and a metal layer according to claim 1.
The ceramic insulating layer is formed using any one of a sol-gel method, an electrophoretic electrodeposition method, an MOCVD method, and a sputtering vapor deposition method. A laminate of ceramic insulating layers and metal layers.
The metal layer is used as a lower electrode forming layer, and an upper electrode forming layer made of a metal material is laminated on the upper surface of the ceramic insulating layer, and used as a capacitor circuit forming material utilizing the dielectric characteristics of the ceramic insulating layer. Item 2. A laminate of a ceramic insulating layer and a metal layer according to Item 1.
The laminate of a ceramic insulating layer and a metal layer according to claim 1, wherein the ceramic insulating layer is obtained by impregnating a resin component between particles or grain boundaries present in the ceramic insulating layer.
A method for producing a laminate of a ceramic insulating layer and a metal layer,
A protective layer forming step of forming a protective layer made of a silicon compound having a layer thickness of 5 nm to 100 nm on the upper surface of the metal layer;
A ceramic insulating layer forming step of forming the ceramic insulating layer on the surface of the protective layer;
A method for producing a laminate of a ceramic insulating layer and a metal layer.