Capacitor and manufacturing method thereof

Abstract

Provided is a capacitor (1) comprising a body (10) in which dielectric layers (13) and electrode layers (11) are laminated, and an external electrode (20) connected to at least a portion of the body, wherein the electrode layers (11) include a heavy edge section (16) in which a connection portion connected to the external electrode is thicker than an internal electrode portion (15), and have a metal edge support layer (12) laminated on the heavy edge section (16).

Description

[Technical Field]

[0001] The present invention relates to a capacitor and a method for manufacturing the same. [Background technology]

[0002] The thin-film polymer laminate capacitor described in Japanese Patent Application Publication No. 2021-19133 has a chip-shaped laminate formed by alternately stacking and bonding dielectric layers and internal electrode layers including a first metal layer formed by vapor-depositing a first metal on the dielectric layer and a second metal layer formed by vapor-depositing a second metal on the first metal layer, and external electrodes formed on one end and the other end of the laminate, wherein the laminate has a first region in which the first metal is formed on the dielectric layer and alternately stacked, and an edge region in which a second metal layer is formed on the layer connected to the one end of the first metal layer and the layer connected to the other end of the first metal layer and alternately stacked, wherein the first region has a capacitor functional region and the edge region has a heavy edge formed. DISCLOSURE OF THE INVENTION

[0003] In film capacitors, a so-called heavy-edge structure is known, in which the internal electrodes in the capacitance-forming portion are thinned while the electrodes in the portions connected to the external electrodes on both end faces are thickened to enhance self-healing properties. Thin-film polymer multilayer capacitors, which include a multilayer structure of resin dielectric layers and electrode layers, are also known to employ a heavy-edge structure to obtain good connectivity with the external electrodes, good voltage resistance characteristics, and the desired capacitance.

[0004] In recent years, there has been a demand for capacitors with even higher withstand voltages and lower ESR. Even when a heavy-edge structure is adopted, if the electrode portions (internal electrode portions) of the capacitor are thinned to sufficiently increase the surface resistivity (sheet resistivity) in order to increase the withstand voltage, the connection portions also become thin. This increases the connection resistance of the connection portions, making it difficult to sufficiently reduce the ESR. On the other hand, if an attempt is made to make only the edge portions thicker, the difference in film thickness with the thin-film internal electrode portions becomes too great, making it difficult to provide capacitors with stable performance at low cost.

[0005] One aspect of the present invention is a capacitor having a body portion formed by laminating a dielectric layer and an electrode layer, and an external electrode connected to at least a portion of the body portion. The electrode layer includes a heavy edge portion where the portion connected to the external electrode is thicker than the internal electrode portion. The capacitor further has at least one metal edge support layer laminated above or below the heavy edge portion.

[0006] Simultaneous production of thin-film internal electrode portions and relatively thick heavy edge portions by techniques such as vapor deposition, coating, or printing can result in manufacturing problems due to differences in the amount of material applied to each portion. For example, it is not easy to produce heavy edge portions, which may be several times thicker, at the same time as producing thin-film internal electrode portions. The capacitor of the present invention includes an electrode layer formed simultaneously with the internal electrode portions and having an integrated heavy edge portion, as well as a metal edge support layer laminated at least above or below the heavy edge portion. The heavy edge portion can be manufactured under the same conditions as the thin-film internal electrode portions with minimal manufacturing burden, and the edge support layer can be further thickened using a metal and / or method different from that of the electrode layer. This allows efficient production of capacitors including edge portions several times thicker than the thin-film internal electrode portions. Furthermore, the laminated heavy edge portion and edge support layer ensure the desired cross-sectional area at the edge portion, allowing capacitors with desired connection performance to be provided at low cost.

[0007] The electrode layer may include a first metal, and the edge support layer may include a second metal having a lower melting point and / or boiling point than the first metal. If these layers are formed by vapor deposition or coating, using a metal with a lower boiling point or melting point for the edge support layer can reduce manufacturing costs. The first metal and the second metal may include at least one of aluminum, zinc, copper, gold, silver, or an alloy containing these. The first metal may include aluminum or an alloy thereof, and the second metal may include zinc or an alloy thereof. The electrode layer may be a layer in which a first metal is vapor-deposited on a dielectric layer, and the edge support layer may be a layer in which a second metal is vapor-deposited on a heavy edge portion. The main body may also include a portion in which a resin vapor-deposited layer forming the dielectric layer, a vapor-deposited layer of the first metal constituting the electrode layer, and a vapor-deposited layer of the second metal constituting the edge support layer are stacked in this order.

[0008] The dielectric layer may include a thermosetting resin, and the thickness of the dielectric layer may be 0.1 μm to 1.5 μm. The surface resistivity of the thin internal electrode portion may be 5 Ω / □ to 80 Ω / □. The combined surface resistivity of the thick heavy edge portion and the edge support layer may be 1 Ω / □ to 20 Ω / □. The electrode layer may include a heavy edge portion separated from the internal electrode portion, and the edge support layer may include a layer laminated at least above or below the separated dummy heavy edge portion. The capacitor may have multiple edge support layers.

[0009] Another aspect of the present invention is a method for manufacturing a capacitor having a body portion formed by laminating a dielectric layer and an electrode layer, at least a portion of the body portion being connected to an external electrode, the method comprising the following steps: 1. An electrode layer is formed on a deposited or film-like dielectric layer, and a heavy edge portion is formed where the connection portion with the external electrode is thicker than the internal electrode portion. 2. Depositing at least one edge support layer over the heavy edge portion.

[0010] An example of a deposition method is vapor deposition. Depositing the dielectric layer may include depositing a resin material constituting the dielectric layer in a reduced pressure environment. Depositing the electrode layer may include depositing a first metal constituting the electrode layer overlying the dielectric layer. Depositing the edge support layer may include depositing a second metal. This manufacturing method may include curing a thermosetting resin material following the depositing of the resin material. Depositing the first metal may include depositing the first metal using a metal mask with a first pattern, and depositing the second metal may include depositing the second metal using a metal mask with a second pattern different from the first pattern. The edge support layer may be deposited using a metal and / or method different from that of the electrode layer.

[0011] This manufacturing method may include, before depositing the electrode layer, patterning a margin on the dielectric layer to separate one of the heavy edge portions from the internal electrode portion, and depositing the edge support layer may include depositing the edge support layer overlying each of the heavy edge portions separated by the margin and the heavy edge portions not separated by the margin.

[0012] Another aspect of the present invention is a system (apparatus) for manufacturing a capacitor having a main body portion on which a dielectric layer and an electrode layer are laminated, at least a portion of which is connected to an external electrode. This system includes a chamber that provides a reduced-pressure environment, a moving unit that moves a workpiece of the main body portion being manufactured within the chamber, a dielectric layer deposition unit that deposits a dielectric layer on the workpiece, an electrode layer deposition unit that deposits an electrode layer on the dielectric layer together with a heavy edge portion where the connection portion with the external electrode is thicker than the internal electrode portion, and at least one edge support layer deposition unit that deposits an edge support layer on the heavy edge portion, where the dielectric layer deposition unit, electrode layer deposition unit, and edge support layer deposition unit are arranged along the moving unit within the chamber. Thus, in this manufacturing apparatus, the dielectric layer, electrode layer, and edge support layer are sequentially laminated in a reduced-pressure environment.

[0013] The dielectric layer deposition unit may include a unit that deposits a resin material constituting the dielectric layer in a reduced pressure environment. The electrode layer deposition unit may include a unit that deposits a first metal constituting the electrode layer overlying the dielectric layer in a reduced pressure environment. The edge support layer deposition unit may include a unit that deposits a second metal in a reduced pressure environment. The system may further include a unit that hardens a thermosetting resin material, disposed along the moving unit in the chamber. The unit that deposits the first metal may include a metal mask having a first pattern, and the unit that deposits the second metal may include a metal mask having a second pattern different from the first pattern. The system may further include a patterning unit that is disposed along the moving unit in the chamber between the dielectric layer deposition unit and the electrode layer deposition unit, and that patterns a margin on the dielectric layer to separate one heavy edge portion from the internal electrode portion. The system may include multiple edge support layer deposition units. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an overview of a capacitor. [Figure 2] FIG. 2 is a cross-sectional view showing an outline of an active layer (stacked body). [Figure 3] 1 is a flowchart showing an outline of a method for manufacturing a capacitor. [Figure 4] 1A to 1C are diagrams showing an example of a manufacturing process for an active layer. [Figure 5] FIG. 1 is a diagram showing an example of a film forming system. [Figure 6] FIG. 1 is a diagram showing an example of a metal mask. MODE FOR CARRYING OUT THE INVENTION

[0015] FIG. 1 shows an example of a capacitor according to the present invention. Examples of capacitors (capacitors) 1 include ceramic capacitors, film capacitors (e.g., metallized film capacitors), and thin-film polymer multilayer capacitors. The capacitor 1 shown in FIG. 1(a) is an example of a thin-film polymer multilayer capacitor. As shown in the cross-sectional view of FIG. 1(b), the body 10 may include an active layer (active bulk layer, core layer, active region) 7 that exhibits capacitance and is located at the center of the thickness direction, dummy layers (dummy bulk layer, dummy region) 8 that do not exhibit capacitance and protective layers (protective region) 9 that are located above and below the active layer 7. The active layer 7 and dummy layer 8 are configured by laminating a resin layer (dielectric layer) 13 and an electrode layer 11, and the protective layer 9 is composed solely of resin. The external electrode 20 is formed to join the electrode layer 11 and resin layer 13 of the active layer 7 and the dummy layer 8, and includes an internal metallikon layer (metallikon connection region, for example, brass metallikon) 21, a copper plating layer 22 covering the periphery thereof, and a tin plating layer 23 covering the outside.

[0016] 2 shows an enlarged cross section of a portion of the active layer 7 of the main body 10. The active layer 7 of the main body 10 is a laminated portion of a dielectric layer 13 and an electrode layer 11. End sides (side surfaces, edge portions) 18 of the dielectric layer 13 and the electrode layer 11 are joined to a metallikon layer 21 of an external electrode 20, and the electrode layer 11 is also electrically connected to the metallikon layer 21. The electrode layer 11 includes a thin-film internal electrode portion 15 that is in wide contact with the dielectric layer 13 inside the active layer 7 and forms a capacitance, and a heavy edge portion 16 whose end side (connection portion) 18 that connects to the external electrode 20 (metallikon layer 21) is thicker than the internal electrode portion 15. The active layer 7 further includes a metallic edge support layer 12 laminated on the heavy edge portion 16.

[0017] An example of the resin constituting the dielectric layer 13 is a thermosetting resin, including an acrylic polymer. An example of a resin that can be used in the thin-film polymer multilayer capacitor 1 is a polymerized version of one or more of tricyclodecane dimethanol dimethacrylate or tricyclodecane dimethanol diacrylate, but the resin constituting the dielectric layer 13 is not limited to this. To provide a small, thin, and high-capacity capacitor, the dielectric layer 13 may be sufficiently thin and have a sufficient number of layers. For example, the thickness of the dielectric layer 13 may be 0.1 to 1.5 μm or 0.2 to 1.2 μm, and the number of layers may be 1,000 or more. The thin-film dielectric layer 13 can be formed to a predetermined thickness by depositing a thermosetting resin as a monomer under a reduced pressure (vacuum) and curing it by irradiation with an electron beam or the like. Capacitors 1 having a dielectric layer 13 made of a thermosetting resin have a higher heat resistance temperature and are reflow-compatible compared to those having a thermoplastic resin, making them more suitable for surface mounting.

[0018] The electrode layer 11 may be formed of at least one of a conductive metal, such as aluminum, zinc, copper, gold, silver, or an alloy containing any of these. For a high-voltage capacitor 1, the withstand voltage can be improved by reducing the thickness of the electrodes that function as a capacitor, i.e., the internal electrode portion 15. For example, the withstand voltage may be 400 V or more, and the thickness of the internal electrode portion 15 may be approximately 1 to 300 nm, or approximately 3 to 100 nm. Surface resistivity may also be used, and the surface resistivity of the internal electrode portion 15 may be 5 to 80 Ω / □ (Ω / sq.), 15 to 80 Ω / □, or 20 to 80 Ω / □.

[0019] Making the electrode layer 11 thin can increase the withstand voltage, but the loss factor (tanδ) and equivalent series resistance (ESR) also increase, which can lead to a decrease in performance as a capacitor. For this reason, the electrode layer 11 includes a heavy edge portion (heavy edge) 16 in which the connection portion 18 with the external electrode 20 is thicker than the internal electrode portion 15. Even if the internal electrode portion 15 is thin, ensuring a sufficient thickness for the connection portion 18 with the external electrode 20, in this example, metallikon 21, reduces tanδ and ESR, improves frequency characteristics, and enables the capacitor to handle high currents.

[0020] Furthermore, the capacitor 1 of this example has an edge support layer 12 deposited on the heavy edge portion 16, and at the connection portion 18 with the metallikon 21, the heavy edge portion 16 and the edge support layer 12 are integrated, i.e., the heavy edge portion 16 and the edge support layer 12 cooperate to control the electrical and mechanical bonding state with the metallikon 21, which is the external electrode. The combined thickness of the heavy edge portion 16 and the edge support layer 12 is thicker than the internal electrode portion 15 and may be 15 to 200 nm or 30 to 100 nm. The combined surface resistivity of the heavy edge portion 16 and the edge support layer 12 may be 1 to 20 Ω / □, 2 to 15 Ω / □, or 3 to 10 Ω / □.

[0021] In this capacitor 1, the thin-film internal electrode portion (internal electrode layer) 15 and the thicker heavy edge portion 16, which form the electrode layer 11, are continuously formed using the same metal, such as aluminum, in the same process. Therefore, there is no boundary between the heavy edge portion 16 and the internal electrode portion 15, and the heavy edge portion 16 and the internal electrode portion 15 are electrically and mechanically integrated, preventing an increase in resistance or a decrease in strength due to the boundary between the heavy edge portion 16 and the internal electrode portion 15.

[0022] On the other hand, by adding the edge support layer 12 later, the desired thickness for the connection portion with the external electrode can be ensured, so the thickness of the heavy edge portion 16, which is formed integrally with the internal electrode portion 15, can be set to a level that allows for reasonable film formation under the same conditions and process as the internal electrode portion 15. This prevents the need to reduce the manufacturing speed to form the heavy edge portion 16, which takes a long time, and prevents difficulty in controlling the shapes and thicknesses of the internal electrode portion 15 and heavy edge portion 16.

[0023] The edge support layer 12 laminated on the heavy edge portion 16 of the electrode layer 11 can be formed at a different timing and by a different process than the electrode layer 11. Therefore, the edge support layer 12 may be made of the same material as the electrode layer 11 or a different material, and the film formation conditions may be different, or the edge support layer 12 may be formed under conditions that prioritize film formation cost and time. An example of the first metal constituting the electrode layer 11 is one that contains aluminum or one of its alloys, and the second metal constituting the edge support layer 12 may be one that contains zinc or one of its alloys.

[0024] For example, the second metal constituting the edge support layer 12 may have a lower melting point and / or boiling point than the first metal constituting the electrode layer 11. A metal with a low melting point can be deposited at lower cost when forming a film by coating or the like. Furthermore, when forming a film by vapor deposition or the like, a metal with a low boiling point can reduce the price and running costs of the film formation equipment and increase the manufacturing speed, thereby improving work efficiency. Furthermore, at the connection portion 18 with the external electrode, the electrical and mechanical performance of the internal electrode portion 15, which functions as a capacitor, can be relatively easily covered to some extent by the heavy edge portion 16, which is deposited in the same process as the internal electrode portion 15. Therefore, the second metal constituting the edge support layer 12 can be selected with priority given to film formation costs, bonding conditions with the metallikon 21, and other factors. Furthermore, since the edge support layer 12 is superimposed on the heavy edge portion 16, which has already been thickened, there is no need to thicken the film excessively. For example, it is possible to control the film formation so that it is within the range of the heavy edge portion 16, making it easier to suppress the impact of the thickened edge portion 18 on the internal electrode portion 15.

[0025] In one example of the capacitor 1, the electrode layer 11 is a layer in which a first metal is vapor-deposited on the dielectric layer 13, and the edge support layer 12 is a layer in which a second metal is vapor-deposited on the heavy edge portion 16. Therefore, the main body 10 may include a portion (active layer) 7 in which a resin vapor-deposited layer that forms the dielectric layer 13, a vapor-deposited layer of the first metal that constitutes the electrode layer 11, and a vapor-deposited layer of the second metal that constitutes the edge support layer 12 are laminated in this order and repeated.

[0026] The electrode layer 11 of the capacitor 1 further includes a dummy heavy edge portion 17 separated from the internal electrode portion 15 by a gap 19, and an edge support layer 12 is laminated on the separated dummy heavy edge portion 17. Because the dummy heavy edge portion 17 is separated from the internal electrode portion 15, it does not contribute to the capacitance of the capacitor 1. However, it is useful for obtaining mechanical connection strength between the external electrode 20 and the metallikon 21, and it maintains or strengthens the connection between the heavy edge portion 16 integrated with the internal electrode portion 15 and the metallikon 21. Therefore, by providing the dummy heavy edge portion 17 and the edge support layer 12 laminated thereon, the tan δ and ESR of the capacitor 1 can be further reduced, resulting in a capacitor with good frequency characteristics and high current capability. In this example, the edge support layer 12 is laminated on the upper side of the heavy edge portions 16 and 17. However, it may also be formed on the lower side or on both the upper and lower sides.

[0027] FIG. 3 shows a flowchart of an example of a process for manufacturing the active layer 7, which is a laminated portion of the main body 10 of the capacitor 1 of this example, using a film forming system (film forming apparatus, film forming system), and FIG. 4 shows a schematic diagram of how each layer is laminated. FIG. 5 shows an overview of a film forming system (film forming apparatus) 50 used as a system for manufacturing the capacitor 1. The film forming system 50 has a vacuum chamber 59 and a drum 55 that rotates in a reduced pressure environment (vacuum environment) within the vacuum chamber 59 and transports the workpiece 40 for manufacturing the main body 10. Note that this example shows an example in which the drum 55 is used as a moving unit (transport device, moving device) on which the workpiece 40 is continuously formed and transported, but multiple workpieces 40 may also be transported intermittently by the drum 55. The deposition system 50, which is a manufacturing apparatus (manufacturing system) using a vapor deposition method, further includes a dielectric layer deposition unit (dielectric layer deposition apparatus) 51 that deposits a dielectric layer 13 on the workpiece 40, an electrode layer deposition unit (electrode layer deposition apparatus) 56 that deposits an electrode layer 11 on the dielectric layer 13 together with a heavy edge portion 16 where a connection portion 18 with the external electrode 20 is thicker than an internal electrode portion 15, and an edge support layer deposition unit (edge ​​support layer deposition apparatus) 57 that deposits an edge support layer 12 on the heavy edge portion 16. The dielectric layer deposition unit 51, the electrode layer deposition unit 56, and the edge support layer deposition unit 57 are arranged along a drum 55, which is a moving unit that moves the workpiece 40 of the main body portion 10 being manufactured, within a chamber 59 that provides a reduced-pressure environment. Thus, in the deposition system 50, the dielectric layer 13, the electrode layer 11, and the edge support layer 12 are successively laminated in a reduced-pressure environment. The deposition system 50 may include multiple edge support layer deposition units 57 and may produce capacitors including multiple edge support layers 12 .

[0028] The film formation system 50 further includes a patterning unit (patterning device) 54 that is disposed along the drum 55 in the chamber 59 between the dielectric layer formation unit 51 and the electrode layer formation unit 56 and that patterns a margin on the dielectric layer 13 to separate one heavy edge portion 16 from the internal electrode portion 15. Specifically, the film formation system 50 includes, arranged in order along the rotating drum 55, a monomer deposition unit (monomer deposition device) 51 that deposits a resin material 43 as a dielectric film formation unit, an electron beam irradiation device 52, a plasma treatment device 53, the patterning device 54, a first deposition unit (first deposition device) 56 that deposits a first metal 41 as an electrode layer film formation unit, and a second deposition unit (second deposition device) 57 that deposits a second metal 42 as an edge support layer film formation unit.

[0029] In the following, the present invention is explained using an example in which the active layer 7, which is the laminated portion, is manufactured by vapor deposition. However, each layer may be formed or applied by other methods such as coating or printing. In the case where an already manufactured material such as a film is used as the dielectric layer, as in a film capacitor, the step of forming the dielectric layer may not be necessary, and may be performed separately from the step of forming the electrode layer.

[0030] First, in step 81, dielectric layer 13 is formed. Specifically, as shown in FIG. 4(a), a thermosetting resin 43 for forming dielectric layer 13 is applied by vapor deposition on a lower layer stacked on drum 55 using monomer vapor deposition unit 51. The applied thermosetting resin 43 is cured by electron beam irradiation device 52 to form dielectric layer 13, and the surface of dielectric layer 13 is then plasma-treated by plasma treatment device 53 for the next step. Therefore, step 81 of forming dielectric layer 13 may include step 81a of vapor-depositing a resin material (thermosetting resin) 43 that constitutes dielectric layer 13 in a reduced-pressure environment, and step 81b of curing thermosetting resin 43.

[0031] Next, in step 82, as shown in FIG. 4(b), before depositing the electrode layer 11, a patterning device 54 is used to pattern a margin (oil margin) 49 on the dielectric layer 13 to separate one heavy edge portion 17 from the internal electrode portion 15.

[0032] Next, in step 83, the electrode layer 11 is deposited on the dielectric layer 13. Specifically, as shown in FIG. 4(c), a first deposition unit 56 deposits a first metal 41 on the dielectric layer 13 through a metal mask 61 of a first pattern to form the electrode layer 11. When depositing the electrode layer 11, the same metal and process are used to form the internal electrode portion 15 as well as the heavy edge portions 16 and 17, where the connection portion 18 with the external electrode 20 is thicker than the internal electrode portion 15. The first metal 41 may include aluminum or an alloy thereof. Although aluminum or an alloy thereof has a slightly higher resistivity (conductivity) than gold or copper, it is low cost, has a relatively low boiling point, and is easy to deposit, making it a suitable material for forming the internal electrode portion 15.

[0033] Next, in step 84, the edge support layer 12 is formed over the heavy edge portions 16 and 17. Specifically, as shown in FIG. 4(d), a second vapor deposition unit 57 deposits a second metal 42 through a metal mask 62 of a second pattern in a limited area so as to overlap the heavy edge portions 16 and 17, thereby forming the edge support layer 12. The second metal 42 may contain zinc or an alloy thereof. The boiling point of zinc is 907°C, which is lower than the boiling point of aluminum, 2520°C. Therefore, it can be installed at a lower cost than an aluminum vapor deposition unit, and running costs can also be reduced. Furthermore, its resistivity is slightly higher than that of aluminum, but is still sufficiently low, making it suitable for use as an electrode constituting the connection portion (edge ​​portion) 18 with the external electrode 20.

[0034] In the previous process, one of the heavy edge portions 17 is separated from the internal electrode portion 15 as a dummy edge portion by the oil patterning process shown in Figure 4(b), and in this process, an edge support layer 12 is formed on top of each of the heavy edge portion 17 separated by the oil margin 49 and the heavy edge portion 16 not separated by the margin.

[0035] In step 85, the above steps are repeated until the number of stacked layers reaches a predetermined value. As a result, as shown in Fig. 4(e), by repeating the steps of Fig. 4(a) to (d), a stacked body in which dielectric layers 13 and electrode layers 11 are stacked together with edge support layers 12 can be manufactured, and by cutting out an appropriate region, a portion that functions as active layer 7 can be manufactured. In step 86, the process moves to the next step for manufacturing capacitor 1.

[0036] FIG. 6( a) shows an example of a metal mask 61 including a first pattern 65 for depositing the electrode layer 11, including the heavy edge portions 16 and 17. FIG. 6( b) shows an example of a metal mask 62 including a second pattern 66 for depositing the edge support layer 12 over the heavy edge portions 16 and 17. The pattern 65 of the metal mask 61 includes a first slit 65a extending horizontally through the center to deposit the internal electrode portion 15, and a second slit 65b extending perpendicularly at regular intervals. The second slit 65b allows for a larger deposition amount at the edge portion than the internal electrode portion 15 deposited through the first slit 65a. This allows for the heavy edge portions 16 and 17 to be deposited thicker than the internal electrode portion 15 in the same process and at the same time.

[0037] On the other hand, if this type of pattern 65 is used to simultaneously deposit a relatively thick heavy edge portion on the internal electrode portion 15, it would be necessary to either lengthen the deposition time or change the area ratio of the first slit 65a and the second slit 65b. In either case, it would be difficult to control the film thickness of the internal electrode portion 15, which could result in a decrease in the area ratio that functions as a capacitor or an inability to achieve an appropriate film thickness, making it impossible to achieve the desired capacitor performance. Therefore, the thickness of the heavy edge portions 16 and 17 that can be deposited with sufficient precision simultaneously with the internal electrode portion 15 is limited.

[0038] The pattern 66 for depositing the edge support layer 12 has linear (slit-like) openings corresponding to the heavy edge portions 16 and 17 so that the second metal 42 is deposited only in the heavy edge portions 16 and 17. This simple shape makes it easy to control the thickness of the edge support layer 12. However, if an attempt is made to deposit a film thick enough to meet the edge requirements using only this pattern 66, it becomes difficult to control the width and thickness of the edge portions, which may result in the desired capacitor performance not being achieved. In this example, by combining the patterns 65 and 66, the advantages of both patterns can be utilized to optimally control the thickness and shape of the connection portion 18. The number of patterns (masks) combined to deposit the edge portions is not limited to two; three or more patterns may be used.

[0039] For example, if the connection portion (edge ​​portion) 18, which requires a thicker film, is formed using only zinc, the thickness of the zinc metal must be increased to reduce the resistance of the connection portion 18. If the zinc in the connection portion 18 is too thick, the electrode cannot be properly extracted, the connection resistance with the external electrode 20 increases, and performance such as ESR deteriorates. Furthermore, if the zinc is formed thinly only in the connection portion 18, reducing the evaporation resistance on the rapidly rotating drum 55 requires a large amount of evaporation, which can easily clog the mask slits. Specifically, if a thick heavy edge portion 16 is formed using aluminum or zinc by evaporation in a single location, the increased evaporation amount leads to the deposition of evaporated metal on the mask, and continuous deposition may result in a smaller (thinner) opening area during the process. Furthermore, continuous production may result in the mask openings and slits becoming clogged. By adding the process of forming the edge support layer 12, the amount of deposition required to thicken the heavy edge portion in each evaporation source can be reduced, thereby reducing the risk of clogging the openings and slits in the mask and further improving manufacturing efficiency and deposition accuracy.

[0040] If an aluminum vapor deposition source were to be installed separately from the aluminum vapor deposition source 56 for the active portion, i.e., the internal electrode portion 15, in order to ensure the thickness of the connection portion 18, the cost of the film-forming apparatus would be significantly higher than that of the zinc vapor deposition source 57, and the apparatus would become larger. Furthermore, the power consumption would increase, leading to higher running costs. If an attempt were made to deposit the connection portion 18 of a predetermined thickness together with the internal electrode portion 15 using the same mask, it would not be easy to deposit the connection portion 18 with the desired shape and thickness, as described above.

[0041] The film-forming apparatus 50 of this embodiment described above uses aluminum heavy edge portions 16 and 17 formed using an aluminum vapor deposition source 56 for the active element, and a zinc edge support layer 12 formed using a separate zinc vapor deposition source 57, to form a connection portion 18 having a desired shape and thickness. This allows the desired edge resistance value of the connection portion 18 to be obtained and the connection resistance value with the external electrode to be reduced. Furthermore, since there is no need for an additional aluminum vapor deposition source, the cost and running costs of the film-forming apparatus 50 can be significantly reduced. Furthermore, by providing multiple vapor deposition sources 57 for forming the edge support layer 12, it is possible to provide a capacitor with thicker film at the edge portions with even greater precision.

[0042] Furthermore, while particular embodiments of the present invention have been described above, various other embodiments and modifications may be devised by those skilled in the art without departing from the scope and spirit of the present invention, and such other embodiments and modifications are within the scope of the following claims, which define the present invention.

Claims

1. A capacitor having a main body in which dielectric layers and electrode layers are repeatedly stacked, and external electrodes connected to at least a portion of the main body, the electrode layer includes a heavy edge portion, a portion connected to the external electrode that is thicker than an internal electrode portion, no boundary is formed between the heavy edge portion and the internal electrode portion, and the heavy edge portion is made of the same metal as the internal electrode portion, The capacitor further comprises at least one edge support layer made of the same metal as the internal electrode portion, at least above or below the heavy edge portion, the edge support layer being formed in a layered manner limited to the region of the heavy edge portion that is thicker and integral with the internal electrode portion, and the dielectric layer and the electrode layer are repeatedly layered together with the edge support layer.

2. A capacitor as described in claim 1, wherein the electrode layer includes a first metal and the edge support layer includes a second metal having a lower melting point and / or boiling point than the first metal.

3. A capacitor as described in claim 2, wherein the first metal and the second metal include at least one of aluminum, zinc, copper, gold, silver, or an alloy containing any of these.

4. The first metal includes aluminum or an alloy thereof; The capacitor of claim 2 or 3, wherein the second metal comprises zinc or one of its alloys.

5. The electrode layer is a layer in which the first metal is vapor-deposited on the dielectric layer, 5. The capacitor according to claim 2, wherein the edge support layer is a layer in which the second metal is vapor-deposited on the heavy edge portion.

6. A capacitor as described in Claim 5, wherein the main body portion includes a portion in which a resin vapor deposition layer forming the dielectric layer, a vapor deposition layer of the first metal constituting the electrode layer, and a vapor deposition layer of the second metal constituting the edge support layer are stacked in sequence.

7. A capacitor described in any one of claims 1 to 6, wherein the dielectric layer comprises a thermosetting resin.

8. A capacitor described in any one of claims 1 to 7, wherein the thickness of the dielectric layer is 0.1 μm to 1.5 μm.

9. A capacitor described in any one of claims 1 to 8, wherein the surface resistivity of the internal electrode portion is 5 Ω / □ to 80 Ω / □.

10. A capacitor described in any one of claims 1 to 9, wherein the combined surface resistivity of the heavy edge portion and the edge support layer is 1 Ω / □ to 20 Ω / □.

11. The electrode layer includes the heavy edge portion separated from the internal electrode portion, The capacitor according to claim 1 , wherein the edge support layer includes a layer laminated above or below the separated heavy edge portion.

12. A capacitor described in any one of claims 1 to 11, having multiple layers of the edge support layer.

13. A method for manufacturing a capacitor having a body portion in which dielectric layers and electrode layers are repeatedly stacked, and at least a portion of the body portion is connected to an external electrode, comprising the steps of: forming an electrode layer on the dielectric layer; forming the electrode layer includes forming a heavy edge portion, in which the connection portion with the external electrode is thicker than the internal electrode portion, using the same metal and the same process as the internal electrode portion, so that the heavy edge portion is integrally formed with the internal electrode portion without any boundary therebetween; forming at least one edge support layer made of the same metal as the internal electrode portion and overlapping it only in the region of the heavy edge portion that is integral with the internal electrode portion and thicker than the internal electrode portion; and forming the dielectric layer, thereby manufacturing the capacitor in which the dielectric layer and the electrode layer, including the edge support layer, are repeatedly stacked.

14. forming the dielectric layer includes vapor-depositing a resin material constituting the dielectric layer in a reduced pressure environment; forming the electrode layer includes depositing a first metal that forms the electrode layer on the dielectric layer; The method of claim 13 , wherein depositing the edge support layer comprises evaporating a second metal.

15. The method of claim 14, further comprising curing the thermosetting resin material following vapor deposition of the resin material.

16. The step of depositing the first metal includes depositing the first metal using a metal mask of a first pattern; The manufacturing method according to claim 14 or 15, wherein the vapor-depositing the second metal includes vapor-depositing using a metal mask having a second pattern different from the first pattern.

17. The method of claim 16, wherein the first metal comprises aluminum or an alloy thereof; 17. The method of any one of claims 14 to 16, wherein the second metal comprises zinc or one of its alloys.

18. The method includes, before depositing the electrode layer, patterning a margin on the dielectric layer to separate one of the heavy edge portions from the internal electrode portion; 18. The manufacturing method according to claim 13, wherein forming the edge support layer includes forming the edge support layer so as to overlap each of the heavy edge portions separated by the margin and the heavy edge portions not separated by the margin.

19. A system for manufacturing a capacitor having a body portion in which dielectric layers and electrode layers are repeatedly stacked, at least a portion of the body portion being connected to an external electrode, comprising: a chamber providing a reduced pressure environment; a moving unit that moves the workpiece of the main body portion being manufactured in the chamber; a dielectric layer deposition unit disposed along the moving unit in the chamber for depositing the dielectric layer on the workpiece, and an electrode layer deposition unit for depositing an electrode layer on the dielectric layer, the electrode layer being deposited on the heavy edge portion where the connection portion with the external electrode is thicker than the internal electrode portion, using the same metal as the internal electrode portion and the same process, continuously and integrally with the internal electrode portion without any boundary between them, and further comprising: The system has at least one edge support layer deposition unit arranged along the moving unit within the chamber and depositing an edge support layer made of the same metal as the internal electrode portion, overlapping only the area of ​​the heavy edge portion that is integral with the internal electrode portion and thicker, and the dielectric layer deposition unit, the electrode layer deposition unit and the at least one edge support layer deposition unit are arranged so that the dielectric layer and the electrode layer, including the edge support layer, are repeatedly stacked.

20. The dielectric layer deposition unit includes a unit that deposits a resin material that constitutes the dielectric layer in the reduced pressure environment, the electrode layer deposition unit includes a unit that deposits a first metal that forms an electrode layer on the dielectric layer in the reduced pressure environment, The system of claim 19 , wherein the edge support layer deposition unit includes a unit that deposits a second metal in the reduced pressure environment.

21. The system described in claim 20, further comprising a unit for hardening the thermosetting resin material, arranged alongside the moving unit within the chamber.

22. The unit for depositing the first metal includes a metal mask of a first pattern; 22. The system of claim 20 or 21, wherein the second metal deposition unit includes a metal mask of a second pattern different from the first pattern.

23. A system described in any one of claims 19 to 22, further comprising a patterning unit arranged within the chamber along the moving unit between the dielectric layer deposition unit and the electrode layer deposition unit, and patterning a margin on the dielectric layer to separate one of the heavy edge portions from the internal electrode portion.

24. A system described in any one of claims 19 to 23, having a plurality of the edge support layer deposition units.

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